US20030211667A1 - Method of fabricating thin film transistor - Google Patents

Method of fabricating thin film transistor Download PDF

Info

Publication number
US20030211667A1
US20030211667A1 US10/454,297 US45429703A US2003211667A1 US 20030211667 A1 US20030211667 A1 US 20030211667A1 US 45429703 A US45429703 A US 45429703A US 2003211667 A1 US2003211667 A1 US 2003211667A1
Authority
US
United States
Prior art keywords
thin film
semiconductor thin
display device
protective film
silicon
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/454,297
Inventor
Makoto Takatoku
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US10/454,297 priority Critical patent/US20030211667A1/en
Publication of US20030211667A1 publication Critical patent/US20030211667A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/78—Field effect transistors with field effect produced by an insulated gate
    • H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66477—Unipolar field-effect transistors with an insulated gate, i.e. MISFET
    • H01L29/66742—Thin film unipolar transistors
    • H01L29/6675—Amorphous silicon or polysilicon transistors
    • H01L29/66757—Lateral single gate single channel transistors with non-inverted structure, i.e. the channel layer is formed before the gate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/12—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/12—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body
    • H01L27/1214—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
    • H01L27/1248—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being other than a semiconductor body, e.g. an insulating body comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof  ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66477—Unipolar field-effect transistors with an insulated gate, i.e. MISFET
    • H01L29/66742—Thin film unipolar transistors
    • H01L29/6675—Amorphous silicon or polysilicon transistors
    • H01L29/66765—Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate

Definitions

  • the present invention relates to a method of fabricating a thin film transistor. More particularly, the invention relates to a technology for keeping clean the condition of an interface between a semiconductor thin film and an insulating film formed on the surface of the semiconductor thin film.
  • thin film transistors have been extensively developed as active devices in active matrix circuits integratedly formed on an insulating substrate.
  • the thin film transistor for example, has a semiconductor thin film of polycrystalline silicon as a device region.
  • a semiconductor thin film of polycrystalline silicon or the like must be patterned in island forms by photolithographic technology.
  • a first gate insulator is first formed on the surface of a semiconductor thin film consisting of polycrystalline silicon. Subsequently, the surface of the semiconductor thin film of polycrystalline silicon is patterned through the first gate insulator without exposing the surface to a photoresist treatment. Thereafter, only the surface of the first gate insulator is partly removed by etching. Further, a second gate insulator is formed on the first gate insulator.
  • the following means have been adopted.
  • the present invention resides in a method of fabricating a thin film transistor having a laminated structure including a semiconductor thin film, an insulating film formed in contact with the surface of the semiconductor thin film, and a gate electrode disposed on the face side or the back side of the semiconductor thin film, and formed on a substrate in a predetermined plan view shape, the method including: a first step of forming a semiconductor thin film having a clean surface over the substrate; a second step of forming a protective film so as to cover the clean surface of the semiconductor thin film; a third step of patterning the semiconductor thin film together with the protective film according to the plan view shape of the thin film transistor; a fourth step of removing the protective film from the upper side of the patterned semiconductor thin film to expose a clean surface of the semiconductor thin film; and a fifth step of forming an insulating film in contact with the exposed surface of the semiconductor thin film.
  • the first step includes forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert the amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
  • the first step may comprise forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
  • the second step may include forming a protective film consisting of an insulating substance.
  • the second step may comprise thermally oxidizing the surface of the semiconductor thin film consisting of silicon to form a protective film consisting of silicon oxide.
  • the second step may comprise forming a protective film by building up silicon oxide through chemical vapor deposition.
  • the second step may comprise forming the protective film by building up a semiconductor substance.
  • the second step comprises forming a protective film having a thickness of not less than 5 nm.
  • the fourth step may comprise removing the protective film by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical.
  • the method comprises a sixth step of forming a gate electrode on the insulating film formed in contact with the clean surface of the semiconductor thin film.
  • a protective film being, for example, insulating is formed on a semiconductor thin film consisting of polycrystalline silicon or the like.
  • the semiconductor thin film is patterned together with the protective film by photolithography, whereby the surface of the semiconductor thin film is protected from contamination in the photolithographic step. Therefore, it is possible to keep clean the interface between the semiconductor thin film and the gate insulator formed on the surface of the semiconductor thin film.
  • the interface between the semiconductor thin film consisting of polycrystalline silicon or the like and the gate insulator can be kept clean, diffusion of impurities in a channel is suppressed, whereby mobility of the thin film transistor is largely improved.
  • the amount of impurities in the gate insulator in contact with the semiconductor thin film or in an interlayer dielectric is reduced, whereby threshold voltage of the thin film transistor can be stabilized.
  • FIG. 1 is a process chart showing a method of fabricating a thin film transistor according to the invention
  • FIG. 2 is also a process chart
  • FIG. 3 is a graph showing the characteristics of a thin film transistor fabricated according to the invention.
  • FIG. 4 is a graph showing the characteristics of a thin film transistor according to the prior art
  • FIG. 5 is a process chart showing another example of the method of fabricating a thin film transistor according to the invention.
  • FIG. 6 is also a process chart
  • FIG. 7 is a schematic perspective view showing an example of a liquid crystal display device according to the invention.
  • FIG. 8 is a schematic sectional view showing an example of an electroluminescence display device according to the invention.
  • FIG. 1 is a process chart showing one example of a first embodiment of the method of fabricating a thin film transistor according to the present invention.
  • the present invention can be applied to both a low temperature process with a highest treatment temperature of less than 600 and a high temperature process with a highest treatment temperature of 700 to 1200, in the method of fabricating a thin film transistor.
  • the present invention can be applied to both a top gate structure and a bottom gate structure. In this embodiment, particularly, a method of fabricating a thin film transistor of the top gate structure by the low temperature process will be shown.
  • a silicon oxide film 6 a and a silicon nitride film 6 b are built up on an insulating substrate 0 consisting of a glass or the like by using, for example, plasma CVD. These insulating films are provided for preventing diffusion of impurities from the substrate 0 . Further, a semiconductor thin film 4 to be a device region (active layer) of a thin film transistor (TFT) is built up on the silicon nitride flm 6 b by, for example, plasma CVD. In this embodiment, the semiconductor thin film 4 is amorphous silicon or polycrystalline silicon with a comparatively small crystal grain size.
  • the semiconductor thin film 4 is irradiated with laser light 50 emitted from, for example, an excimer laser light source, whereby the amorphous silicon or polycrystalline silicon with a comparatively small crystal grain size is converted to polycrystalline silicon with a comparatively large crystal grain size.
  • the crystallizing annealing by use of laser light may be replaced by a melting crystallizing technique. Namely, after the semiconductor thin film consisting of amorphous silicon or polycrystalline silicon with a comparatively small grain size is formed, a heating treatment by use of a furnace is carried out to obtain polycrystalline silicon with a comparatively large grain size through solid phase growth.
  • a protective film PF is provided so as to cover a clean surface of the crystallized semiconductor thin film 5 .
  • a silicon oxide film is built up to a thickness of about 10 nm by use of plasma CVD, for example. Therefore, an insulating protective film PF is provided.
  • the surface of the semiconductor thin film 5 consisting of polycrystalline silicon may be thermally oxidized to obtain a protective film PF consisting of silicon oxide.
  • a semiconductor substance such as silicon may be built up to form the protective film PF.
  • the protective film PF is preferably formed to have a thickness of at least 5 nm.
  • the semiconductor thin film 5 is patterned together with the protective film PF into an island form, according to the plan view shape of the thin film transistor.
  • a photoresist RM is applied to the protective film PF formed over the substrate 0 , and is patterned into a predetermined plan view shape by exposure to light and development.
  • the semiconductor thin film 5 and the protective film PF are simultaneously patterned by etching.
  • the etching may be either dry etching or wet etching.
  • the photoresist RM thus used is removed by ashing or by use of a chemical liquid.
  • the protective film PF contaminated in the etching step is removed from the upper side of the patterned semiconductor thin film 5 , to expose a clean surface.
  • the chemical liquid is disposed without being circulatorily used in chemical liquid treating equipment, after once making contact with the substrate 0 .
  • the protective film PF is removed by wet etching in which the chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical.
  • a gate insulator 3 is formed in contact with the exposed surface of the semiconductor thin film 5 .
  • SiO 2 is grown in a thickness of 50 to 400 nm by plasma CVD method, normal pressure CVD method, reduced pressure CVD method, ECR-CVD method, sputtering method or the like, to provide the gate insulator 3 .
  • the film thickness of the gate insulator 3 is 100 nm.
  • ion implantation for adjustment of threshold voltage (Vth) is carried out to inject B+ ion into the semiconductor thin film 5 in a dose of about 0.5 ⁇ 10 12 to 4 ⁇ 10 12 /cm 2 .
  • the acceleration voltage is about 50 KeV.
  • the Vth ion implantation may be carried out before the formation of the gate insulator 3 .
  • a gate electrode 1 is formed on the gate insulator 3 .
  • Al, Ti, Mo, W, Ta, doped polycrystalline silicon or the like or an alloy of these substances is built up in a thickness of 200 to 800 nm, and is patterned into a predetermined shape to provide the gate electrode 1 .
  • P+ ion is injected into the semiconductor thin film 5 by an ion injection method using mass separation, to provide an LDD region. This ion injection is carried out over the entire surface of the insulating substrate 0 , with the gate electrode 1 as a mask.
  • the dose is 6 ⁇ 10 12 to 5 ⁇ 10 13 /cm 2 .
  • the acceleration voltage is 100 KeV, for example.
  • a doping gas As a doping gas, a mixture gas of PH 3 /H 2 is used. After the ion injection into the LDD region, a resist pattern is provided so as to cover the gate electrode 1 and the vicinity thereof, and P+ ion is injected in a high concentration by a mass non-separation type ion shower doping method, to provide a source region S and a drain region D. In this case, the dose is about 1 ⁇ 10 15 /cm 2 , for example.
  • the acceleration voltage is 100 KeV.
  • As a doping gas a hydrogen-diluted 20% PH 3 gas was used.
  • CMOS circuit In the case of producing a CMOS circuit, a resist pattern for a p-channel thin film transistor is formed, then the doping gas is changed to a 5 to 20% B 2 H 6 /H 2 gas, and ion is injected in a dose of about 1 ⁇ 10 15 to 3 ⁇ 10 15 /cm 2 .
  • the acceleration voltage is about 50 KeV.
  • the formation of the source region S and the drain region D may be carried out by use of a mass separation type ion injection apparatus.
  • an interlayer dielectric 7 consisting of SiO 2 is formed in a thickness of about 600 nm so as to cover the gate electrode 1 .
  • SiN X is built up in a thickness of about 200 to 400 nm to form a passivation film (cap film) 8 .
  • annealing is carried out in a nitrogen gas at a temperature of 350 to 400 for about 1 hour, whereby hydrogen contained in the interlayer dielectric 7 is diffused into the semiconductor thin film 5 . Thereafter, a contact hole is opened.
  • a film of Mo, Al or the like is formed on the passivation film 8 by sputtering, and is patterned into a predetermined shape to produce a wiring electrode 9 .
  • a flattening layer 10 consisting of an acrylic resin or the like is applied in a thickness of about 1 m, and a contact hole is opened in the flattening layer 10 .
  • a transparent conductor film consisting of ITO, IXO or the like is sputtered onto the flattening layer 10 , and is patterned in a predetermined shape to produce a pixel electrode 11 .
  • annealing is carried out in N 2 at a temperature of about 220 for about 30 minutes.
  • FIG. 3 is a graph showing the operation characteristics of a thin film transistor fabricated according to the present invention.
  • the axis of abscissa is gate voltage VGS
  • the axis of ordinate is drain current IDS.
  • the number of samples is two.
  • the drain current IDS rises up steeply as the gate voltage VGS increases, which means good threshold characteristics.
  • the surface of the semiconductor thin film is kept clean, and the amount of impurities in the gate insulator in contact with the clean surface is reduced, whereby the threshold voltage can be stabilized as shown in the figure.
  • the interface between the semiconductor thin film and the gate insulator can be clean, and diffusion of impurities in the channel is decreased, whereby mobility of the thin film transistor is largely enhanced.
  • the mobility in the case of an N channel type thin film transistor, the mobility is about 150 cm 2 /V.s. In the case of a P channel type thin film transistor, the mobility is about 100 cm 2 /V.s.
  • FIG. 4 is a reference graph showing the characteristics of a thin film transistor fabricated by a method according to the prior art.
  • a natural oxidized film remaining on the surface is removed by pure water and hydrofluoric acid, and a gate insulator is formed thereon.
  • the thickness of the natural oxidized film is about 1 to 2 nm. Since the cleanliness of the surface cannot be kept by mere removal of the natural oxidized film, the threshold characteristics are not steep, as compared with FIG. 3.
  • the mobility is about 46 cm 2 /V.s in the case of N channel type, and is as low as about 28 cm 2 /V.s in the case of P channel type.
  • the grain size of the polycrystalline silicon constituting the semiconductor thin film is set to be about 250 nm, both in the case of the present invention and in the case of the prior art example.
  • FIGS. 5A to 5 E are process charts showing one example of a second embodiment of the method of fabricating a thin film transistor according to the present invention.
  • This is a method of fabricating a thin film transistor of the bottom gate type which has a laminated structure comprising a semiconductor thin film, an interlayer dielectric formed in contact with the surface of the semiconductor thin film, and a gate electrode disposed on the back side of the semiconductor thin film, and which is formed on a substrate in a predetermined plan view shape.
  • a method of fabricating a thin film transistor of the N channel type is shown, but the same applies to the case of the P channel type by merely changing the kind of impurities.
  • a film of Al, Ta, Mo, W, Cr, Cu, or an alloy of these elements is formed in a thickness of 100 to 250 nm on an insulating substrate 0 consisting of a glass or the like, and is patterned to provide a gate electrode 1 .
  • a gate insulator is formed on the gate electrode 1 .
  • the gate insulator a double-layer structure of a gate nitride film 2 (SiN X ) and a gate oxide film 3 (SiO 2 ) was used.
  • the gate nitride film 2 was built up by a plasma CVD method (PCVD method) using a mixture of SiH 4 gas and NH 3 gas as a raw material gas.
  • the plasma CVD may be replaced by normal pressure CVD or reduced pressure CVD.
  • the gate nitride film 2 was built up in a thickness of 50 nm.
  • the gate oxide film 3 is formed in a thickness of about 200 nm.
  • a semiconductor thin film 4 consisting of amorphous silicon was formed in a thickness of about 30 to 80 nm on the gate oxide film 3 .
  • the film formation of the double-layer gate insulator and the film formation of the amorphous semiconductor thin film 4 was carried out continuously, without breaking the vacuum in a film-forming chamber.
  • dehydrogenation annealing is carried out in which a heat treatment at a temperature of 400 to 450 is carried out in a nitrogen atmosphere for about 1 to 2 hours, to discharge hydrogen contained in the amorphous semiconductor thin film 4 .
  • Vth ion implantation is carried out in order to control the Vth of the thin film transistor.
  • B+ ion was injected in a dose of about 1 ⁇ 10 12 to 6 ⁇ 10 12 /cm 2 .
  • a line beam of ion shaped to a 620 nm width was used.
  • An injection method using a line beam of ion previously subjected to mass separation is a favorable method for uniformly introducing an impurity ion into a semiconductor thin film formed on a large glass substrate.
  • irradiation with laser light 50 is carried out to crystallize the amorphous semiconductor thin film 4 .
  • an excimer laser beam can be used as the laser light 50 .
  • So-called laser annealing is a potent means for crystallizing a semiconductor thin film at a process temperature of not higher than 600.
  • the crystallization is carried out by irradiating the amorphous semiconductor thin film 4 with laser light 50 excited in a pulse form and shaped in a rectangular or belt-like shape.
  • crystallization of the semiconductor thin film may be carried out by a solid phase growth method.
  • a protective film PF is formed so as to cover the clean surface of the polycrystalline semiconductor thin film 5 .
  • silicon oxide is built up by chemical vapor deposition to provide the protective film PF.
  • a photoresist RM is applied to the protective film PF.
  • the photoresist is subjected to exposure to light and development, and is patterned in an island form according to the shape of the device region of thin film transistor.
  • the protective film PF and the polycrystalline semiconductor thin film 5 are together patterned by dry etching or wet etching. Since the surface of the semiconductor thin film 5 is covered by the protective film PF, the surface would not be contaminated in the etching step.
  • the photoresist RM thus used is removed by an ashing treatment. Further, the protective film PF used is removed to expose the clean surface of the polycrystalline semiconductor thin film 5 .
  • the protective film PF is removed by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical, to ensure that the surface of the polycrystalline semiconductor thin film 5 is not contaminated.
  • an insulating film 6 a is formed in contact with the exposed surface of the semiconductor thin film 5 .
  • SiO 2 was built up in a thickness of about 100 to 300 nm by a plasma CVD method.
  • SiO 2 was formed by decomposition of silane gas.
  • the insulating film 6 a consisting of SiO 2 is patterned to provide a stopper film 6 .
  • a back side exposure technique is used so that the stopper film 6 is patterned in match with the gate electrode 1 .
  • a clean portion of the polycrystalline semiconductor thin film 5 located beneath the stopper film 6 is protected as a channel region Ch.
  • ion implantation is carried out to inject an impurity (for example, P+ ion) into the semiconductor thin film 5 , thereby forming LDD regions.
  • the dose is 4 ⁇ 10 12 to 5 ⁇ 10 13 /cm 2 , for example.
  • the acceleration voltage is, for example, 10 KeV.
  • a photoresist is applied and patterned so as to cover the stopper film 6 and the LDD regions on both side thereof, and, with the patterned photoresist as a mask, an impurity (for example, P+ ion) is injected in a high concentration to form a source region S and a drain region D.
  • impurity for example, P+ ion
  • ion doping ion shower
  • This is a technique of injecting an impurity by acceleration by electric field without conducting mass separation.
  • impurity was injected in a dose of about 1 ⁇ 10 15 /cm 2 by using PH 3 gas diluted with H 2 , to form the source region S and the drain region D.
  • the region of the n-channel thin film transistor is covered by a photoresist, then the impurity is changed from P+ ion to B+ ion, and ion doping is carried out in a dose of about 1 ⁇ 10 15 /cm 2 .
  • B 2 H 6 gas diluted with H 2 is used.
  • the injection of impurity may be carried out by using a mass separation type ion implantation apparatus.
  • a film of SiO 2 is formed in a thickness of about 200 nm to provide an interlayer dielectric 7 .
  • a film of SiN X is formed in a thickness of about 200 to 400 nm by a plasma CVD method to provide a passivation film (cap film) 8 .
  • a heat treatment at about 350 is carried out in a nitrogen gas or forming gas atmosphere or in vacuum for 1 hour, whereby hydrogen atoms contained in the interlayer dielectric 7 are diffused into the semiconductor thin film 5 .
  • a contact hole is opened, then Mo, Al or the like is sputtered in a thickness of 200 to 400 nm, and is patterned in a predetermined shape to provide a wiring electrode 9 .
  • a flattening layer 10 consisting of an acrylic resin or the like is applied in a thickness of about 1 m, and a contact hole is opened.
  • a transparent conductor film consisting of ITO, IXO or the like is sputtered onto the flattening layer 10 , and is patterned in a predetermined shape to provide a pixel electrode 11 . In the case where ITO is used, annealing is carried out at 220 in N 2 for about 30 minutes.
  • this display device has a panel structure comprising a pair of insulating substrates 101 and 102 and an electro-optical substance 103 held therebetween.
  • the electro-optical substance 103 for example, a liquid crystal material is used.
  • a pixel array portion 104 and a driving circuit portion are integratedly formed on the lower insulating substrate 101 .
  • the driving circuit portion is divided into a vertical driving circuit 105 and a horizontal driving circuit 106 .
  • a terminal portion 107 for external connection is provided at top end of a peripheral portion of the insulating substrate 101 .
  • the terminal portion 107 is connected to the vertical driving circuit 105 and the horizontal driving circuit 106 through a wiring 108 .
  • the pixel array portion 104 comprises gate wirings 109 in a row form and signal wirings 110 in a column form. At each of intersections of both wirings, a pixel electrode 111 and a thin film transistor 112 for driving the pixel electrode 111 are provided.
  • a gate electrode of the thin film transistor 112 is connected to a corresponding gate wiring 109 , a drain region is connected to a corresponding pixel electrode 111 , and a source region is connected to a corresponding signal wiring 110 .
  • the gate wiring 109 is connected to the vertical driving circuit 105 , whereas the signal wiring 110 is connected to the horizontal driving circuit 106 .
  • the thin film transistor 112 for switching and driving the pixel electrode 111 and thin film transistors contained in the vertical driving circuit 105 and the horizontal driving circuit 106 are fabricated according to the present invention.
  • FIG. 8 is a schematic partly sectional view showing another embodiment of the display apparatus according to the present invention.
  • an organic electroluminescence device OLED is used as a pixel.
  • the OLED comprises an anode A, an organic layer 210 and a cathode K laminated in this order.
  • the anode A is separated for every pixel, consists of, for example, chromium and is basically light-reflective.
  • the cathode K is connected in common to individual pixels, has a laminated structure of, for example, an extremely thin metallic layer 211 and a transparent conductor layer 212 , and is basically light-transmissive.
  • the thin film transistor TFT for driving the OLED comprises a gate electrode 1 formed on a substrate 0 consisting of a glass or the like, a gate insulator 23 laminated thereon, and a semiconductor thin film 5 laminated on the upper side of the gate electrode 1 through the gate insulator 23 .
  • the semiconductor thin film 5 consists, for example, of a silicon thin film made to be polycrystalline by laser annealing.
  • the thin film transistor TFT comprises a source region S, a channel region Ch and a drain region D providing a path of electric current supplied to the OLED.
  • the channel region Ch is located directly above the gate electrode 1 .
  • the thin film transistor TFT having the bottom gate structure is covered by an interlayer dielectric 7 , and a signal wiring 9 and a drain electrode 200 are formed thereon.
  • the above-mentioned OLED is provided in a film form through another interlayer dielectric 91 .
  • the anode A of the OLED is electrically connected to the thin film transistor TFT through the drain electrode 200 .

Abstract

A thin film transistor has a laminated structure comprising a semiconductor thin film, a gate insulator formed in contact with the surface of the semiconductor thin film, and a gate electrode disposed on the face side of the semiconductor thin film, and is formed on a substrate in a predetermined plan view shape. To fabricate the thin film transistor, first, a first step is carried out in which a semiconductor thin film having a clean surface is formed over the substrate. Next, a second step is carried out in which a protective film PF is formed so as to cover the clean surface of the semiconductor thin film. Further, in a third step, the semiconductor thin film is patterned together with the protective film PF according to the predetermined plan view shape of the thin film transistor. Thereafter, a fourth step is carried out in which the protective film PF is removed from the upper side of the patterned semiconductor thin film to expose a clean surface. Subsequently, a fifth step is carried out in which a gate insulator is formed in contact with the exposed surface of the semiconductor thin film.

Description

    RELATED APPLICATION DATA
  • The present application claims priority to Japanese Application No. P2000-154049 filed May 25, 2000 which application is incorporated herein by reference to the extent permitted by law [0001]
    • BACKGROUND OF THE INVENTION
  • The present invention relates to a method of fabricating a thin film transistor. More particularly, the invention relates to a technology for keeping clean the condition of an interface between a semiconductor thin film and an insulating film formed on the surface of the semiconductor thin film. [0002]
  • In recent years, thin film transistors have been extensively developed as active devices in active matrix circuits integratedly formed on an insulating substrate. The thin film transistor, for example, has a semiconductor thin film of polycrystalline silicon as a device region. In order to isolate individual thin film transistors, a semiconductor thin film of polycrystalline silicon or the like must be patterned in island forms by photolithographic technology. [0003]
  • However, there has been the problem that when polycrystalline silicon is directly patterned, deposition of a large amount of impurities uncontrollable in photolithographic step occurs, and the impurities would diffuse into semiconductor thin film or an insulating film in contact therewith in latter steps or would segregate to the surface of the semiconductor thin film. In such a situation, it is difficult to control the characteristics of the thin film transistor. [0004]
  • Countermeasure against the above problem is disclosed, for example, in Japanese Patent Laid-open No. Hei 10-116989. According to the disclosure, a first gate insulator is first formed on the surface of a semiconductor thin film consisting of polycrystalline silicon. Subsequently, the surface of the semiconductor thin film of polycrystalline silicon is patterned through the first gate insulator without exposing the surface to a photoresist treatment. Thereafter, only the surface of the first gate insulator is partly removed by etching. Further, a second gate insulator is formed on the first gate insulator. According to the prior art, however, although the layer of polycrystalline silicon is not exposed to the atmosphere and is kept clean, a contaminated interface is generated between the first gate insulator and the second gate insulator. With electric charges trapped at the contaminated interface, there may arise the problem that the characteristics of the thin film transistor cannot be controlled. [0005]
    • SUMMARY OF THE INVENTION
  • It is an object of the present invention to provide a technology of fabrication of a thin film transistor by which a semiconductor thin film constituting a device region of the thin film transistor can be patterned in island forms while keeping a clean surface condition. In order to attain the above object, the following means have been adopted. Namely, the present invention resides in a method of fabricating a thin film transistor having a laminated structure including a semiconductor thin film, an insulating film formed in contact with the surface of the semiconductor thin film, and a gate electrode disposed on the face side or the back side of the semiconductor thin film, and formed on a substrate in a predetermined plan view shape, the method including: a first step of forming a semiconductor thin film having a clean surface over the substrate; a second step of forming a protective film so as to cover the clean surface of the semiconductor thin film; a third step of patterning the semiconductor thin film together with the protective film according to the plan view shape of the thin film transistor; a fourth step of removing the protective film from the upper side of the patterned semiconductor thin film to expose a clean surface of the semiconductor thin film; and a fifth step of forming an insulating film in contact with the exposed surface of the semiconductor thin film. [0006]
  • Preferably, the first step includes forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert the amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size. The first step may comprise forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth. Besides, the second step may include forming a protective film consisting of an insulating substance. In this case, the second step may comprise thermally oxidizing the surface of the semiconductor thin film consisting of silicon to form a protective film consisting of silicon oxide. The second step may comprise forming a protective film by building up silicon oxide through chemical vapor deposition. Alternatively, the second step may comprise forming the protective film by building up a semiconductor substance. Preferably, the second step comprises forming a protective film having a thickness of not less than 5 nm. The fourth step may comprise removing the protective film by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical. Preferably, the method comprises a sixth step of forming a gate electrode on the insulating film formed in contact with the clean surface of the semiconductor thin film. [0007]
  • According to the present invention, a protective film being, for example, insulating is formed on a semiconductor thin film consisting of polycrystalline silicon or the like. The semiconductor thin film is patterned together with the protective film by photolithography, whereby the surface of the semiconductor thin film is protected from contamination in the photolithographic step. Therefore, it is possible to keep clean the interface between the semiconductor thin film and the gate insulator formed on the surface of the semiconductor thin film. [0008]
  • According to the present invention, since the interface between the semiconductor thin film consisting of polycrystalline silicon or the like and the gate insulator can be kept clean, diffusion of impurities in a channel is suppressed, whereby mobility of the thin film transistor is largely improved. In addition, the amount of impurities in the gate insulator in contact with the semiconductor thin film or in an interlayer dielectric is reduced, whereby threshold voltage of the thin film transistor can be stabilized.[0009]
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a process chart showing a method of fabricating a thin film transistor according to the invention; [0010]
  • FIG. 2 is also a process chart; [0011]
  • FIG. 3 is a graph showing the characteristics of a thin film transistor fabricated according to the invention; [0012]
  • FIG. 4 is a graph showing the characteristics of a thin film transistor according to the prior art; [0013]
  • FIG. 5 is a process chart showing another example of the method of fabricating a thin film transistor according to the invention; [0014]
  • FIG. 6 is also a process chart; [0015]
  • FIG. 7 is a schematic perspective view showing an example of a liquid crystal display device according to the invention; and [0016]
  • FIG. 8 is a schematic sectional view showing an example of an electroluminescence display device according to the invention.[0017]
    • DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. [0018]
  • FIG. 1 is a process chart showing one example of a first embodiment of the method of fabricating a thin film transistor according to the present invention. The present invention can be applied to both a low temperature process with a highest treatment temperature of less than 600 and a high temperature process with a highest treatment temperature of 700 to 1200, in the method of fabricating a thin film transistor. Besides, as to the form of the thin film transistor, the present invention can be applied to both a top gate structure and a bottom gate structure. In this embodiment, particularly, a method of fabricating a thin film transistor of the top gate structure by the low temperature process will be shown. [0019]
  • First, as shown in FIG. 1A, a [0020] silicon oxide film 6 a and a silicon nitride film 6 b are built up on an insulating substrate 0 consisting of a glass or the like by using, for example, plasma CVD. These insulating films are provided for preventing diffusion of impurities from the substrate 0. Further, a semiconductor thin film 4 to be a device region (active layer) of a thin film transistor (TFT) is built up on the silicon nitride flm 6 b by, for example, plasma CVD. In this embodiment, the semiconductor thin film 4 is amorphous silicon or polycrystalline silicon with a comparatively small crystal grain size. Thereafter, the semiconductor thin film 4 is irradiated with laser light 50 emitted from, for example, an excimer laser light source, whereby the amorphous silicon or polycrystalline silicon with a comparatively small crystal grain size is converted to polycrystalline silicon with a comparatively large crystal grain size. In some cases, the crystallizing annealing by use of laser light may be replaced by a melting crystallizing technique. Namely, after the semiconductor thin film consisting of amorphous silicon or polycrystalline silicon with a comparatively small grain size is formed, a heating treatment by use of a furnace is carried out to obtain polycrystalline silicon with a comparatively large grain size through solid phase growth.
  • Next, as shown in FIG. 1B, a protective film PF is provided so as to cover a clean surface of the crystallized semiconductor [0021] thin film 5. In this embodiment, a silicon oxide film is built up to a thickness of about 10 nm by use of plasma CVD, for example. Therefore, an insulating protective film PF is provided. In some cases, instead of using the CVD (Chemical Vapor Deposition), the surface of the semiconductor thin film 5 consisting of polycrystalline silicon may be thermally oxidized to obtain a protective film PF consisting of silicon oxide. Alternatively, a semiconductor substance such as silicon may be built up to form the protective film PF. In order to keep the cleanliness of the surface of the semiconductor thin film 5, the protective film PF is preferably formed to have a thickness of at least 5 nm.
  • Subsequently, as shown in FIG. 1C, the semiconductor [0022] thin film 5 is patterned together with the protective film PF into an island form, according to the plan view shape of the thin film transistor. Specifically, a photoresist RM is applied to the protective film PF formed over the substrate 0, and is patterned into a predetermined plan view shape by exposure to light and development. By using the thus patterned photoresist RM as a mask, the semiconductor thin film 5 and the protective film PF are simultaneously patterned by etching. The etching may be either dry etching or wet etching.
  • Thereafter, as shown in FIG. 1D, the photoresist RM thus used is removed by ashing or by use of a chemical liquid. Then, the protective film PF contaminated in the etching step is removed from the upper side of the patterned semiconductor [0023] thin film 5, to expose a clean surface. In this case, in order not to damage the polycrystalline silicon, it is preferable to use a wet treatment with an HF-containing chemical liquid. Besides, in order to keep the cleanliness of the chemical liquid itself, the chemical liquid is disposed without being circulatorily used in chemical liquid treating equipment, after once making contact with the substrate 0. In addition, in order to obviate the situation where impurities turn round from the substrate within a chemical liquid reservoir, it is preferable to pour the chemical liquid from above the substrate 0, instead of immersing the substrate in a chemical liquid reservoir. Namely, the protective film PF is removed by wet etching in which the chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical.
  • Subsequently, as shown in FIG. 2A, a [0024] gate insulator 3 is formed in contact with the exposed surface of the semiconductor thin film 5. For example, SiO2 is grown in a thickness of 50 to 400 nm by plasma CVD method, normal pressure CVD method, reduced pressure CVD method, ECR-CVD method, sputtering method or the like, to provide the gate insulator 3. In this example, the film thickness of the gate insulator 3 is 100 nm. If necessary, ion implantation for adjustment of threshold voltage (Vth) is carried out to inject B+ ion into the semiconductor thin film 5 in a dose of about 0.5×1012 to 4×1012/cm2. In this case, the acceleration voltage is about 50 KeV. The Vth ion implantation may be carried out before the formation of the gate insulator 3.
  • Subsequently, as shown in FIG. 2B, a [0025] gate electrode 1 is formed on the gate insulator 3. For example, Al, Ti, Mo, W, Ta, doped polycrystalline silicon or the like or an alloy of these substances is built up in a thickness of 200 to 800 nm, and is patterned into a predetermined shape to provide the gate electrode 1. Next, P+ ion is injected into the semiconductor thin film 5 by an ion injection method using mass separation, to provide an LDD region. This ion injection is carried out over the entire surface of the insulating substrate 0, with the gate electrode 1 as a mask. The dose is 6×1012 to 5×1013/cm2. The acceleration voltage is 100 KeV, for example. As a doping gas, a mixture gas of PH3/H2 is used. After the ion injection into the LDD region, a resist pattern is provided so as to cover the gate electrode 1 and the vicinity thereof, and P+ ion is injected in a high concentration by a mass non-separation type ion shower doping method, to provide a source region S and a drain region D. In this case, the dose is about 1×1015/cm2, for example. The acceleration voltage is 100 KeV. As a doping gas, a hydrogen-diluted 20% PH3 gas was used. In the case of producing a CMOS circuit, a resist pattern for a p-channel thin film transistor is formed, then the doping gas is changed to a 5 to 20% B2H6/H2 gas, and ion is injected in a dose of about 1×1015 to 3×1015/cm2. The acceleration voltage is about 50 KeV. The formation of the source region S and the drain region D may be carried out by use of a mass separation type ion injection apparatus.
  • Finally, as shown in FIG. 2C, an [0026] interlayer dielectric 7 consisting of SiO2 is formed in a thickness of about 600 nm so as to cover the gate electrode 1. By a plasma CVD method, SiNX is built up in a thickness of about 200 to 400 nm to form a passivation film (cap film) 8. At this stage, annealing is carried out in a nitrogen gas at a temperature of 350 to 400 for about 1 hour, whereby hydrogen contained in the interlayer dielectric 7 is diffused into the semiconductor thin film 5. Thereafter, a contact hole is opened. Further, a film of Mo, Al or the like is formed on the passivation film 8 by sputtering, and is patterned into a predetermined shape to produce a wiring electrode 9. Further, a flattening layer 10 consisting of an acrylic resin or the like is applied in a thickness of about 1 m, and a contact hole is opened in the flattening layer 10. A transparent conductor film consisting of ITO, IXO or the like is sputtered onto the flattening layer 10, and is patterned in a predetermined shape to produce a pixel electrode 11. In the case of ITO, annealing is carried out in N2 at a temperature of about 220 for about 30 minutes.
  • FIG. 3 is a graph showing the operation characteristics of a thin film transistor fabricated according to the present invention. In the graph, the axis of abscissa is gate voltage VGS, and the axis of ordinate is drain current IDS. The number of samples is two. As apparent from the graph, the drain current IDS rises up steeply as the gate voltage VGS increases, which means good threshold characteristics. According to the present invention, the surface of the semiconductor thin film is kept clean, and the amount of impurities in the gate insulator in contact with the clean surface is reduced, whereby the threshold voltage can be stabilized as shown in the figure. In addition, the interface between the semiconductor thin film and the gate insulator can be clean, and diffusion of impurities in the channel is decreased, whereby mobility of the thin film transistor is largely enhanced. For example, in the case of an N channel type thin film transistor, the mobility is about 150 cm[0027] 2/V.s. In the case of a P channel type thin film transistor, the mobility is about 100 cm2/V.s.
  • FIG. 4 is a reference graph showing the characteristics of a thin film transistor fabricated by a method according to the prior art. In the reference example, after a semiconductor thin film is patterned into an island form, a natural oxidized film remaining on the surface is removed by pure water and hydrofluoric acid, and a gate insulator is formed thereon. The thickness of the natural oxidized film is about 1 to 2 nm. Since the cleanliness of the surface cannot be kept by mere removal of the natural oxidized film, the threshold characteristics are not steep, as compared with FIG. 3. In addition, the mobility is about 46 cm[0028] 2/V.s in the case of N channel type, and is as low as about 28 cm2/V.s in the case of P channel type. Incidentally, the grain size of the polycrystalline silicon constituting the semiconductor thin film is set to be about 250 nm, both in the case of the present invention and in the case of the prior art example.
  • FIGS. 5A to [0029] 5E are process charts showing one example of a second embodiment of the method of fabricating a thin film transistor according to the present invention. This is a method of fabricating a thin film transistor of the bottom gate type which has a laminated structure comprising a semiconductor thin film, an interlayer dielectric formed in contact with the surface of the semiconductor thin film, and a gate electrode disposed on the back side of the semiconductor thin film, and which is formed on a substrate in a predetermined plan view shape. In this embodiment, for convenience, a method of fabricating a thin film transistor of the N channel type is shown, but the same applies to the case of the P channel type by merely changing the kind of impurities. First, as shown in FIG. 5A, a film of Al, Ta, Mo, W, Cr, Cu, or an alloy of these elements is formed in a thickness of 100 to 250 nm on an insulating substrate 0 consisting of a glass or the like, and is patterned to provide a gate electrode 1.
  • Next, as shown in FIG. 5B, a gate insulator is formed on the [0030] gate electrode 1. In this embodiment, as the gate insulator, a double-layer structure of a gate nitride film 2 (SiNX) and a gate oxide film 3 (SiO2) was used. The gate nitride film 2 was built up by a plasma CVD method (PCVD method) using a mixture of SiH4 gas and NH3 gas as a raw material gas. Incidentally, the plasma CVD may be replaced by normal pressure CVD or reduced pressure CVD. In this embodiment, the gate nitride film 2 was built up in a thickness of 50 nm. Continuously to the formation of the gate nitride film 2, the gate oxide film 3 is formed in a thickness of about 200 nm. Continuously, a semiconductor thin film 4 consisting of amorphous silicon was formed in a thickness of about 30 to 80 nm on the gate oxide film 3. The film formation of the double-layer gate insulator and the film formation of the amorphous semiconductor thin film 4 was carried out continuously, without breaking the vacuum in a film-forming chamber. In the case where plasma CVD is used in the film formations, so-called dehydrogenation annealing is carried out in which a heat treatment at a temperature of 400 to 450 is carried out in a nitrogen atmosphere for about 1 to 2 hours, to discharge hydrogen contained in the amorphous semiconductor thin film 4.
  • Here, as required, Vth ion implantation is carried out in order to control the Vth of the thin film transistor. In this example, B+ ion was injected in a dose of about 1×10[0031] 12 to 6×1012/cm2. In the Vth ion implantation, a line beam of ion shaped to a 620 nm width was used. An injection method using a line beam of ion previously subjected to mass separation is a favorable method for uniformly introducing an impurity ion into a semiconductor thin film formed on a large glass substrate. Next, irradiation with laser light 50 is carried out to crystallize the amorphous semiconductor thin film 4. As the laser light 50, an excimer laser beam can be used. So-called laser annealing is a potent means for crystallizing a semiconductor thin film at a process temperature of not higher than 600. In this embodiment, the crystallization is carried out by irradiating the amorphous semiconductor thin film 4 with laser light 50 excited in a pulse form and shaped in a rectangular or belt-like shape. In some cases, crystallization of the semiconductor thin film may be carried out by a solid phase growth method.
  • Subsequently, as shown in FIG. 5C, a protective film PF is formed so as to cover the clean surface of the polycrystalline semiconductor [0032] thin film 5. For example, silicon oxide is built up by chemical vapor deposition to provide the protective film PF.
  • Subsequently, as sown in FIG. 5D, a photoresist RM is applied to the protective film PF. The photoresist is subjected to exposure to light and development, and is patterned in an island form according to the shape of the device region of thin film transistor. With the patterned photoresist RM as a mask, the protective film PF and the polycrystalline semiconductor [0033] thin film 5 are together patterned by dry etching or wet etching. Since the surface of the semiconductor thin film 5 is covered by the protective film PF, the surface would not be contaminated in the etching step.
  • Next, as shown in FIG. 5E, the photoresist RM thus used is removed by an ashing treatment. Further, the protective film PF used is removed to expose the clean surface of the polycrystalline semiconductor [0034] thin film 5. In this case, the protective film PF is removed by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using the chemical, to ensure that the surface of the polycrystalline semiconductor thin film 5 is not contaminated.
  • Subsequently, as shown in FIG. 6A, an insulating [0035] film 6 a is formed in contact with the exposed surface of the semiconductor thin film 5. Here, SiO2 was built up in a thickness of about 100 to 300 nm by a plasma CVD method. In this example, SiO2 was formed by decomposition of silane gas.
  • Subsequently, as shown in FIG. 6B, the insulating [0036] film 6 a consisting of SiO2 is patterned to provide a stopper film 6. In this case, a back side exposure technique is used so that the stopper film 6 is patterned in match with the gate electrode 1. A clean portion of the polycrystalline semiconductor thin film 5 located beneath the stopper film 6 is protected as a channel region Ch. Then, with the stopper film 6 as a mask, ion implantation is carried out to inject an impurity (for example, P+ ion) into the semiconductor thin film 5, thereby forming LDD regions. At this time, the dose is 4×1012 to 5×1013/cm2, for example. The acceleration voltage is, for example, 10 KeV. Further, a photoresist is applied and patterned so as to cover the stopper film 6 and the LDD regions on both side thereof, and, with the patterned photoresist as a mask, an impurity (for example, P+ ion) is injected in a high concentration to form a source region S and a drain region D. For the injection of impurity, for example, ion doping (ion shower) can be used. This is a technique of injecting an impurity by acceleration by electric field without conducting mass separation. In this example, impurity was injected in a dose of about 1×1015/cm2 by using PH3 gas diluted with H2, to form the source region S and the drain region D. Though not shown, in the case of fabricating a p-channel thin film transistor, the region of the n-channel thin film transistor is covered by a photoresist, then the impurity is changed from P+ ion to B+ ion, and ion doping is carried out in a dose of about 1×1015/cm2. For example, B2H6 gas diluted with H2 is used. Here, the injection of impurity may be carried out by using a mass separation type ion implantation apparatus.
  • Finally, as shown in FIG. 6C, a film of SiO[0037] 2 is formed in a thickness of about 200 nm to provide an interlayer dielectric 7. After the formation of the interlayer dielectric 7, a film of SiNX is formed in a thickness of about 200 to 400 nm by a plasma CVD method to provide a passivation film (cap film) 8. At this stage, a heat treatment at about 350 is carried out in a nitrogen gas or forming gas atmosphere or in vacuum for 1 hour, whereby hydrogen atoms contained in the interlayer dielectric 7 are diffused into the semiconductor thin film 5. Thereafter, a contact hole is opened, then Mo, Al or the like is sputtered in a thickness of 200 to 400 nm, and is patterned in a predetermined shape to provide a wiring electrode 9. Further, a flattening layer 10 consisting of an acrylic resin or the like is applied in a thickness of about 1 m, and a contact hole is opened. A transparent conductor film consisting of ITO, IXO or the like is sputtered onto the flattening layer 10, and is patterned in a predetermined shape to provide a pixel electrode 11. In the case where ITO is used, annealing is carried out at 220 in N2 for about 30 minutes.
  • Referring now to FIG. 7, an example of a liquid crystal display device using a thin film transistor fabricated according to the present invention will be described. As shown, this display device has a panel structure comprising a pair of insulating [0038] substrates 101 and 102 and an electro-optical substance 103 held therebetween. As the electro-optical substance 103, for example, a liquid crystal material is used. A pixel array portion 104 and a driving circuit portion are integratedly formed on the lower insulating substrate 101. The driving circuit portion is divided into a vertical driving circuit 105 and a horizontal driving circuit 106. A terminal portion 107 for external connection is provided at top end of a peripheral portion of the insulating substrate 101. The terminal portion 107 is connected to the vertical driving circuit 105 and the horizontal driving circuit 106 through a wiring 108. The pixel array portion 104 comprises gate wirings 109 in a row form and signal wirings 110 in a column form. At each of intersections of both wirings, a pixel electrode 111 and a thin film transistor 112 for driving the pixel electrode 111 are provided. A gate electrode of the thin film transistor 112 is connected to a corresponding gate wiring 109, a drain region is connected to a corresponding pixel electrode 111, and a source region is connected to a corresponding signal wiring 110. The gate wiring 109 is connected to the vertical driving circuit 105, whereas the signal wiring 110 is connected to the horizontal driving circuit 106. The thin film transistor 112 for switching and driving the pixel electrode 111 and thin film transistors contained in the vertical driving circuit 105 and the horizontal driving circuit 106 are fabricated according to the present invention.
  • FIG. 8 is a schematic partly sectional view showing another embodiment of the display apparatus according to the present invention. In this embodiment, an organic electroluminescence device OLED is used as a pixel. The OLED comprises an anode A, an [0039] organic layer 210 and a cathode K laminated in this order. The anode A is separated for every pixel, consists of, for example, chromium and is basically light-reflective. The cathode K is connected in common to individual pixels, has a laminated structure of, for example, an extremely thin metallic layer 211 and a transparent conductor layer 212, and is basically light-transmissive. When a forward voltage (about 10 V) is impressed between the anode A and the cathode K of the OLED having such a structure, injection of carrier such as electrons and positive holes occurs, and light emission is observed. The operation of the OLED is considered to be light emission by excitons produced by the positive holes injected from the anode A and electrons injected from the cathode K.
  • On the other hand, the thin film transistor TFT for driving the OLED comprises a [0040] gate electrode 1 formed on a substrate 0 consisting of a glass or the like, a gate insulator 23 laminated thereon, and a semiconductor thin film 5 laminated on the upper side of the gate electrode 1 through the gate insulator 23. The semiconductor thin film 5 consists, for example, of a silicon thin film made to be polycrystalline by laser annealing. The thin film transistor TFT comprises a source region S, a channel region Ch and a drain region D providing a path of electric current supplied to the OLED. The channel region Ch is located directly above the gate electrode 1. The thin film transistor TFT having the bottom gate structure is covered by an interlayer dielectric 7, and a signal wiring 9 and a drain electrode 200 are formed thereon. On these components, the above-mentioned OLED is provided in a film form through another interlayer dielectric 91. The anode A of the OLED is electrically connected to the thin film transistor TFT through the drain electrode 200.
  • While the preferred embodiment of the present invention has been described using the specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. [0041]

Claims (60)

What is claimed is:
1. A method of fabricating a thin film transistor having a laminated structure comprising a semiconductor thin film, an insulating film formed in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and formed on a substrate in a predetermined plan view shape, said method comprising:
a first step of forming a semiconductor thin film having a clean surface over said substrate,
a second step of forming a protective film so as to cover said clean surface of said semiconductor thin film,
a third step of patterning said semiconductor thin film together with said protective film according to said plan view shape of said thin film transistor,
a fourth step of removing said protective film from the upper side of said patterned semiconductor thin film to expose said clean surface of said semiconductor thin film, and
a fifth step of forming an insulating film in contact with said exposed surface of said semiconductor thin film.
2. A method of fabricating a thin film transistor according to claim 1, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
3. A method of fabricating a thin film transistor according to claim 1, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
4. A method of fabricating a thin film transistor according to claim 1, wherein said second step comprises forming a protective film consisting of an insulating substance.
5. A method of fabricating a thin film transistor according to claim 4, wherein said second step comprises thermally oxidizing the surface of a semiconductor thin film consisting of silicon to form a protective film consisting of silicon oxide.
6. A method of fabricating a thin film transistor according to claim 4, wherein said second step comprises forming a protective film by building up silicon oxide through chemical vapor deposition.
7. A method of fabricating a thin film transistor according to claim 1, wherein said second step comprises forming said protective film by building up a semiconductor substance.
8. A method of fabricating a thin film transistor according to claim 1, wherein said second step comprises forming a protective film having a thickness of not less than 5 nm.
9. A method of fabricating a thin film transistor according to claim 1, wherein said fourth step comprises removing said protective film by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
10. A method of fabricating a thin film transistor according to claim 1, further comprising a sixth step of forming a gate electrode on said insulating film formed in contact with the clean surface of said semiconductor thin film.
11. A thin film transistor having a laminated structure comprising a semiconductor thin film, an insulating film formed in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and formed on a substrate in a predetermined plan view shape, wherein
said semiconductor thin film is provided by forming a semiconductor thin film over said substrate in the state of having a clean surface, thereafter forming a protective film so as to cover said clean surface, then pattering said semiconductor thin film together with said protective film according to said predetermined plan view shape, and removing said protective film to expose said clean surface, and
said insulating film is formed in contact with said exposed surface of said semiconductor thin film.
12. A thin film transistor according to claim 11, wherein said semiconductor thin film is provided by forming a film of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
13. A thin film transistor according to claim 11, wherein said semiconductor thin film is provided by forming a film of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
14. A thin film transistor according to claim 11, wherein said protective film consists of an insulating substance.
15. A thin film transistor according to claim 14, wherein said insulating substance is silicon oxide obtained by thermally oxidizing the surface of a semiconductor thin film consisting of silicon.
16. A thin film transistor according to claim 14, wherein said insulating substance is silicon oxide built up by chemical vapor deposition.
17. A thin film transistor according to claim 11, wherein said protective film consists of a semiconductor substance.
18. A thin film transistor according to claim 11, wherein said protective film has a thickness of not less than 5 nm.
19. A thin film transistor according to claim 11, wherein said protective film is removed by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
20. A thin film transistor according to claim 11, wherein said gate electrode is disposed on said insulating film formed in contact with said clean surface of said semiconductor thin film.
21. A method of producing a liquid crystal display device comprising a pair of substrates jointed to each other with a gap therebetween, a liquid crystal disposed in said gap, pixel electrodes and thin film transistors for driving said pixel electrodes provided on one of said substrates, and a counter electrode provided on the other of said substrates, wherein
said thin film transistor has a laminated structure comprising a semiconductor thin film, an insulating film provided in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and
said thin film transistor is formed on one of said substrates in a predetermined plan view shape by:
a first step for forming a semiconductor thin film having a clean surface over a substrate,
a second step of forming a protective film so as to cover said clean surface of said semiconductor thin film,
a third step of patterning said semiconductor thin film together with said protective film according to said plan view shape of said thin film transistor,
a fourth step of removing said protective film from the upper side of said patterned semiconductor thin film to expose said clean surface, and
a fifth step of forming an insulating film in contact with said exposed surface of said semiconductor thin film.
22. A method of producing a liquid crystal display device according to claim 21, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
23. A method of producing a liquid crystal display device according to claim 21, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
24. A method of producing a liquid crystal display device according to claim 21, wherein said second step comprises forming a protective film consisting of an insulating substance.
25. A method of producing a liquid crystal display device according to claim 24, wherein said second step comprises thermally oxidizing the surface of a semiconductor thin film consisting of silicon to form a protective film consisting of silicon oxide.
26. A method of producing a liquid crystal display device according to claim 24, wherein said second step comprises forming a protective film by building up silicon oxide through chemical vapor deposition.
27. A method of producing a liquid crystal display device according to claim 21, wherein said second step comprises forming said protective film by building up a semiconductor substance.
28. A method of producing a liquid crystal display device according to claim 21, wherein said second step comprises forming a protective film having a thickness of not less than 5 nm.
29. A method of producing a liquid crystal display device according to claim 21, wherein said fourth step comprises removing said protective film by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
30. A method of producing a liquid crystal display device according to claim 21, further comprising a sixth step of forming a gate electrode on said insulating film formed in contact with the clean surface of said semiconductor thin film.
31. A liquid crystal display device comprising a pair of substrates jointed to each other with a gap therebetween, a liquid crystal disposed in said gap, pixel electrodes and thin film transistors for driving said pixel electrodes provided on one of said substrates, and a counter electrode provided on the other of said substrates, wherein
said thin film transistor has a laminated structure comprising a semiconductor thin film, an insulating film formed in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and is formed on one of said substrates in a predetermined plan view shape,
said semiconductor thin film is provided by forming a semiconductor thin film over said substrate in the state of having a clean surface, thereafter forming a protective film so as to cover said clean surface, then pattering said semiconductor thin film together with said protective film according to said predetermined plan view shape, and removing said protective film to expose said clean surface, and
said insulating film is formed in contact with said exposed surface of said semiconductor thin film.
32. A liquid crystal display device according to claim 31, wherein said semiconductor thin film is provided by forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
33. A liquid crystal display device according to claim 31, wherein said semiconductor thin film is provided by forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
34. A liquid crystal display device according to claim 31, wherein said protective film consists of an insulating substance.
35. A liquid crystal display device according to claim 34, wherein said insulating substance is silicon oxide obtained by thermally oxidizing the surface of a semiconductor thin film consisting of silicon.
36. A liquid crystal display device according to claim 34, wherein said insulating substance is silicon oxide built up by chemical vapor deposition.
37. A liquid crystal display device according to claim 31, wherein said protective film consists of a semiconductor substance.
38. A liquid crystal display device according to claim 31, wherein said protective film has a thickness of not less than 5 nm.
39. A liquid crystal display device according to claim 31, wherein said protective film is removed by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
40. A liquid crystal display device according to claim 31, wherein said gate electrode is disposed on said insulating film formed in contact with said clean surface of said semiconductor thin film.
41. A method of producing an electroluminescence display device comprising electroluminescence devices and thin film transistors for driving said electroluminescence devices on a substrate, wherein
said thin film transistor has a laminated structure comprising a semiconductor thin film, an insulating film provided in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and
said thin film transistor is formed on said substrate in a predetermined plan view shape by:
a first step for forming a semiconductor thin film having a clean surface over a substrate,
a second step of forming a protective film so as to cover said clean surface of said semiconductor thin film,
a third step of patterning said semiconductor thin film together with said protective film according to said plan view shape of said thin film transistor,
a fourth step of removing said protective film from the upper side of said patterned semiconductor thin film to expose said clean surface, and
a fifth step of forming an insulating film in contact with said exposed surface of said semiconductor thin film.
42. A method of producing an electroluminescence display device according to claim 41, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
43. A method of producing an electroluminescence display device according to claim 41, wherein said first step comprises forming a semiconductor thin film consisting of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
44. A method of producing an electroluminescence display device according to claim 41, wherein said second step comprises forming a protective film consisting of an insulating substance.
45. A method of producing an electroluminescence display device according to claim 44, wherein said second step comprises thermally oxidizing the surface of a semiconductor thin film consisting of silicon to form a protective film consisting of silicon oxide.
46. A method of producing an electroluminescence display device according to claim 44, wherein said second step comprises forming a protective film by building up silicon oxide through chemical vapor deposition.
47. A method of producing an electroluminescence display device according to claim 41, wherein said second step comprises forming said protective film by building up a semiconductor substance.
48. A method of producing an electroluminescence display device according to claim 41, wherein said second step comprises forming a protective film having a thickness of not less than 5 nm.
49. A method of producing an electroluminescence display device according to claim 41, wherein said fourth step comprises removing said protective film by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
50. A method of producing an electroluminescence display device according to claim 41, further comprising a sixth step of forming a gate electrode on said insulating film formed in contact with the clean surface of said semiconductor thin film.
51. An electroluminescence display device comprising electroluminescence devices and thin film transistors for driving said electroluminescence devices on a substrate, wherein
said thin film transistor has a laminated structure comprising a semiconductor thin film, an insulating film formed in contact with the surface of said semiconductor thin film, and a gate electrode disposed on the face side or the back side of said semiconductor thin film, and is formed on said substrate in a predetermined plan view shape,
said semiconductor thin film is provided by forming a semiconductor thin film over said substrate in the state of having a clean surface, thereafter forming a protective film so as to cover said clean surface, then pattering said semiconductor thin film together with said protective film according to said predetermined plan view shape, and removing said protective film to expose said clean surface, and
said insulating film is formed in contact with said exposed surface of said semiconductor thin film.
52. An electroluminescence display device according to claim 51, wherein said semiconductor thin film is provided by forming a film of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by irradiation with laser light to convert said amorphous or polycrystalline silicon to polycrystalline silicon having a comparatively large grain size.
53. An electroluminescence display device according to claim 51, wherein said semiconductor thin film is provided by forming a film of silicon being amorphous or being polycrystalline with a comparatively small grain size, followed by a heat treatment to obtain polycrystalline silicon having a comparatively large grain size through solid phase growth.
54. An electroluminescence display device according to claim 51, wherein said protective film consists of an insulating substance.
55. An electroluminescence display device according to claim 54, wherein said insulating substance is silicon oxide obtained by thermally oxidizing the surface of a semiconductor thin film consisting of silicon.
56. An electroluminescence display device according to claim 54, wherein said insulating substance is silicon oxide built up by chemical vapor deposition.
57. An electroluminescence display device according to claim 51, wherein said protective film consists of a semiconductor substance.
58. An electroluminescence display device according to claim 51, wherein said protective film has a thickness of not less than 5 nm.
59. An electroluminescence display device according to claim 51, wherein said protective film is removed by wet etching in which a chemical having a dissolving function is made to act in a flowing manner without circulatorily using said chemical.
60. An electroluminescence display device according to claim 51, wherein said gate electrode is disposed on said insulating film formed in contact with said clean surface of said semiconductor thin film.
US10/454,297 2000-05-25 2003-06-04 Method of fabricating thin film transistor Abandoned US20030211667A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US10/454,297 US20030211667A1 (en) 2000-05-25 2003-06-04 Method of fabricating thin film transistor

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2000154049A JP2001332741A (en) 2000-05-25 2000-05-25 Method for manufacturing thin film transistor
JPP2000-154049 2000-05-25
US09/865,104 US6599783B2 (en) 2000-05-25 2001-05-24 Method of fabricating a thin film including a protective layer as a mask
US10/454,297 US20030211667A1 (en) 2000-05-25 2003-06-04 Method of fabricating thin film transistor

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US09/865,104 Division US6599783B2 (en) 2000-05-25 2001-05-24 Method of fabricating a thin film including a protective layer as a mask

Publications (1)

Publication Number Publication Date
US20030211667A1 true US20030211667A1 (en) 2003-11-13

Family

ID=18659203

Family Applications (3)

Application Number Title Priority Date Filing Date
US09/865,104 Expired - Fee Related US6599783B2 (en) 2000-05-25 2001-05-24 Method of fabricating a thin film including a protective layer as a mask
US10/453,952 Abandoned US20030211668A1 (en) 2000-05-25 2003-06-04 Method of fabricating thin film transistor
US10/454,297 Abandoned US20030211667A1 (en) 2000-05-25 2003-06-04 Method of fabricating thin film transistor

Family Applications Before (2)

Application Number Title Priority Date Filing Date
US09/865,104 Expired - Fee Related US6599783B2 (en) 2000-05-25 2001-05-24 Method of fabricating a thin film including a protective layer as a mask
US10/453,952 Abandoned US20030211668A1 (en) 2000-05-25 2003-06-04 Method of fabricating thin film transistor

Country Status (4)

Country Link
US (3) US6599783B2 (en)
JP (1) JP2001332741A (en)
KR (1) KR20010107764A (en)
TW (1) TW519764B (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070228382A1 (en) * 2002-06-11 2007-10-04 Shunpei Yamazaki Light emitting device and manufacturing method thereof
US8253327B2 (en) 2007-06-28 2012-08-28 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element, light-emitting device, and electronic device
CN103137495A (en) * 2011-11-30 2013-06-05 株式会社半导体能源研究所 Method for manufacturing semiconductor device
US9105855B2 (en) 2004-05-20 2015-08-11 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US9166180B2 (en) 2001-06-20 2015-10-20 Semiconductor Energy Laboratory Co., Ltd. Light emitting device having an organic light emitting diode that emits white light
CN109585566A (en) * 2018-11-14 2019-04-05 惠科股份有限公司 A kind of array substrate, the production method of array substrate and display panel

Families Citing this family (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002076352A (en) * 2000-08-31 2002-03-15 Semiconductor Energy Lab Co Ltd Display device and its manufacturing method
US6893887B2 (en) 2001-01-18 2005-05-17 Semiconductor Energy Laboratory Co., Ltd. Process for producing a light emitting device
KR100766493B1 (en) * 2001-02-12 2007-10-15 삼성전자주식회사 Tft lcd
US6720198B2 (en) * 2001-02-19 2004-04-13 Semiconductor Energy Laboratory Co., Ltd. Light emitting device and manufacturing method thereof
SG102681A1 (en) * 2001-02-19 2004-03-26 Semiconductor Energy Lab Light emitting device and method of manufacturing the same
KR100437475B1 (en) * 2001-04-13 2004-06-23 삼성에스디아이 주식회사 Method for fabricating display device used in flat display device
US7211828B2 (en) 2001-06-20 2007-05-01 Semiconductor Energy Laboratory Co., Ltd. Light emitting device and electronic apparatus
JP2003168645A (en) * 2001-12-03 2003-06-13 Hitachi Ltd Semiconductor thin film device, its manufacturing method, and image display device
US7749818B2 (en) 2002-01-28 2010-07-06 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and method of manufacturing the same
TW200302511A (en) * 2002-01-28 2003-08-01 Semiconductor Energy Lab Semiconductor device and method of manufacturing the same
TWI261358B (en) * 2002-01-28 2006-09-01 Semiconductor Energy Lab Semiconductor device and method of manufacturing the same
CN100350617C (en) * 2002-03-05 2007-11-21 株式会社半导体能源研究所 Semiconductor element and semiconductor device using said element
US7579771B2 (en) 2002-04-23 2009-08-25 Semiconductor Energy Laboratory Co., Ltd. Light emitting device and method of manufacturing the same
US7786496B2 (en) * 2002-04-24 2010-08-31 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and method of manufacturing same
JP2003317971A (en) 2002-04-26 2003-11-07 Semiconductor Energy Lab Co Ltd Light emitting device and its producing method
US7303945B2 (en) 2002-06-06 2007-12-04 Nec Corporation Method for forming pattern of stacked film and thin film transistor
US6933241B2 (en) 2002-06-06 2005-08-23 Nec Corporation Method for forming pattern of stacked film
US7897979B2 (en) 2002-06-07 2011-03-01 Semiconductor Energy Laboratory Co., Ltd. Light emitting device and manufacturing method thereof
JP4216008B2 (en) * 2002-06-27 2009-01-28 株式会社半導体エネルギー研究所 LIGHT EMITTING DEVICE AND ITS MANUFACTURING METHOD, AND VIDEO CAMERA, DIGITAL CAMERA, GOGGLE TYPE DISPLAY, CAR NAVIGATION, PERSONAL COMPUTER, DVD PLAYER, ELECTRONIC GAME EQUIPMENT, OR PORTABLE INFORMATION TERMINAL HAVING THE LIGHT EMITTING DEVICE
SG130013A1 (en) * 2002-07-25 2007-03-20 Semiconductor Energy Lab Method of fabricating light emitting device
KR101061882B1 (en) * 2002-09-11 2011-09-02 가부시키가이샤 한도오따이 에네루기 켄큐쇼 Light emitting device and manufacturing method thereof
KR100466628B1 (en) * 2002-11-12 2005-01-15 삼성에스디아이 주식회사 Flat panel display and fabrication method thereof
JP4373086B2 (en) 2002-12-27 2009-11-25 株式会社半導体エネルギー研究所 Light emitting device
US7112455B2 (en) 2004-06-10 2006-09-26 Freescale Semiconductor, Inc Semiconductor optical devices and method for forming
US20070054429A1 (en) * 2005-08-25 2007-03-08 Tsuan-Lun Lung Back panel manufacturing process
US7675078B2 (en) * 2005-09-14 2010-03-09 Chunghwa Picture Tubes, Ltd. Pixel structure
JP2009206508A (en) * 2008-01-31 2009-09-10 Canon Inc Thin film transistor and display
KR101510212B1 (en) * 2008-06-05 2015-04-10 삼성전자주식회사 Method of manufacturing oxide semiconductor thin film transistor
KR101352237B1 (en) * 2008-08-13 2014-01-16 엘지디스플레이 주식회사 Organic Light Emitting Display and Manufacturing Method of the same
KR20110090408A (en) * 2010-02-03 2011-08-10 삼성전자주식회사 Manufacturing method of thin film and metal line for display using the same, thin film transistor array panel and method for manufacturing the same
JP6190192B2 (en) * 2013-07-16 2017-08-30 ソニーセミコンダクタソリューションズ株式会社 Radiation imaging apparatus and radiation imaging display system
KR20150137214A (en) * 2014-05-28 2015-12-09 삼성디스플레이 주식회사 Organic light-emitting display apparatus and manufacturing the same
KR20170109182A (en) * 2016-03-18 2017-09-28 삼성디스플레이 주식회사 Thin film transistor substrate, display device comprising the same, and method for manufacturing thin film transistor substrate

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5847411A (en) * 1996-04-11 1998-12-08 Matsushita Electric Industrial Co., Ltd. Semiconductor device having a channel region including a vacancy-introduced polysilicon layer
US6392720B1 (en) * 1998-12-17 2002-05-21 Lg Electronics, Inc. Substrate structure of a liquid crystal display and a manufacturing method thereof
US6420246B1 (en) * 1997-02-17 2002-07-16 Semiconductor Energy Laboratory Co., Ltd. Method of gettering a metal element for accelerating crystallization of silicon by phosphorous

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3035451B2 (en) * 1994-07-19 2000-04-24 大日本スクリーン製造株式会社 Substrate surface treatment equipment
JPH08153699A (en) * 1994-09-16 1996-06-11 Semiconductor Energy Lab Co Ltd Manufacture of thin-film semiconductor device
JP3463971B2 (en) * 1996-12-26 2003-11-05 出光興産株式会社 Organic active EL light emitting device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5847411A (en) * 1996-04-11 1998-12-08 Matsushita Electric Industrial Co., Ltd. Semiconductor device having a channel region including a vacancy-introduced polysilicon layer
US6420246B1 (en) * 1997-02-17 2002-07-16 Semiconductor Energy Laboratory Co., Ltd. Method of gettering a metal element for accelerating crystallization of silicon by phosphorous
US6392720B1 (en) * 1998-12-17 2002-05-21 Lg Electronics, Inc. Substrate structure of a liquid crystal display and a manufacturing method thereof

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9166180B2 (en) 2001-06-20 2015-10-20 Semiconductor Energy Laboratory Co., Ltd. Light emitting device having an organic light emitting diode that emits white light
US9178168B2 (en) 2001-06-20 2015-11-03 Semiconductor Energy Laboratory Co., Ltd. White light emitting device
US9276224B2 (en) 2001-06-20 2016-03-01 Semiconductor Energy Laboratory Co., Ltd. Organic light emitting device having dual flexible substrates
US8362487B2 (en) 2002-06-11 2013-01-29 Semiconductor Energy Laboratory Co., Ltd. Light emitting device comprising film having hygroscopic property and transparency
US20070228382A1 (en) * 2002-06-11 2007-10-04 Shunpei Yamazaki Light emitting device and manufacturing method thereof
US9614012B2 (en) 2004-05-20 2017-04-04 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US11683952B2 (en) 2004-05-20 2023-06-20 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US11063236B2 (en) 2004-05-20 2021-07-13 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US9105855B2 (en) 2004-05-20 2015-08-11 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US9349775B2 (en) 2004-05-20 2016-05-24 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element and display device
US10784465B2 (en) 2004-05-20 2020-09-22 Semiconductor Energy Laboratory Co., Ltd. Light-emitting device having white light emission
US8941301B2 (en) 2007-06-28 2015-01-27 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element, light-emitting device, electronic device, and method for fabricating light-emitting element
US8253327B2 (en) 2007-06-28 2012-08-28 Semiconductor Energy Laboratory Co., Ltd. Light-emitting element, light-emitting device, and electronic device
US10224433B2 (en) 2011-11-30 2019-03-05 Semiconductor Energy Laboratory Co., Ltd. Method for manufacturing semiconductor device
US9608123B2 (en) 2011-11-30 2017-03-28 Semiconductor Energy Laboratory Co., Ltd. Method for manufacturing semiconductor device
CN103137495A (en) * 2011-11-30 2013-06-05 株式会社半导体能源研究所 Method for manufacturing semiconductor device
CN109585566A (en) * 2018-11-14 2019-04-05 惠科股份有限公司 A kind of array substrate, the production method of array substrate and display panel

Also Published As

Publication number Publication date
US6599783B2 (en) 2003-07-29
TW519764B (en) 2003-02-01
US20030211668A1 (en) 2003-11-13
US20020066902A1 (en) 2002-06-06
JP2001332741A (en) 2001-11-30
KR20010107764A (en) 2001-12-07

Similar Documents

Publication Publication Date Title
US6599783B2 (en) Method of fabricating a thin film including a protective layer as a mask
US6995048B2 (en) Thin film transistor and active matrix type display unit production methods therefor
JP3398453B2 (en) Method for manufacturing thin film transistor
KR100402845B1 (en) Manufacturing method of liquid crystal display device
JPH07321338A (en) Semiconductor integrated circuit and manufacture
US20070034874A1 (en) Semiconductor device and method for manufacturing the same
US20060003505A1 (en) Method of fabricating display device
US20050196910A1 (en) Method of manufacturing a semiconductor device and electronic equipment
US7061019B2 (en) Semiconductor circuit array substrate with a photo-electric sensor portion
KR100585873B1 (en) Polycrystalline liquid crystal display device and fabfication method thereof
US7851282B2 (en) Method for forming thin film devices for flat panel displays
KR101157915B1 (en) A polycrystalline silicon thin film transistor and a fabricating method with the same and a polycrystalline silicon thin film transistor palte with the same
US20090256151A1 (en) Display substrate and method of manufacturing the same
JPH11163366A (en) Manufacture of thin-film transistor
KR101599280B1 (en) Method of fabricating an array substrate
KR101588448B1 (en) Array substrate including thin film transistor of polycrystalline silicon and method of fabricating the same
JP3345756B2 (en) Method for manufacturing semiconductor device
KR100498629B1 (en) Manufacturing method of liquid crystal display device
JPH0582552A (en) Manufacture of thin film transistor
JP2000036602A (en) Thin-film transistor, manufacture of it, and display device
JP2001274413A (en) Method of manufacturing thin film transistor
JP2002190604A (en) Thin-film transistor, liquid crystal display device using the thin-film transistor and electroluminescence display device
JP2001320055A (en) Thin-film semiconductor device and manufacturing method thereof
KR20040058699A (en) The Manufacturing Method of Thin Film Transistors Array on glass
JP2001284597A (en) Semiconductor device and manufacturing method thereof

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION