US20080035997A1 - Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor - Google Patents
Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor Download PDFInfo
- Publication number
- US20080035997A1 US20080035997A1 US11/833,080 US83308007A US2008035997A1 US 20080035997 A1 US20080035997 A1 US 20080035997A1 US 83308007 A US83308007 A US 83308007A US 2008035997 A1 US2008035997 A1 US 2008035997A1
- Authority
- US
- United States
- Prior art keywords
- source
- fin
- drain
- integrated circuit
- channel
- 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
Links
- 230000005669 field effect Effects 0.000 title abstract description 65
- 238000000034 method Methods 0.000 title description 36
- 239000000758 substrate Substances 0.000 claims abstract description 25
- 239000000463 material Substances 0.000 claims description 20
- 229910052710 silicon Inorganic materials 0.000 claims description 19
- 239000010703 silicon Substances 0.000 claims description 19
- 230000004888 barrier function Effects 0.000 claims description 17
- 238000009792 diffusion process Methods 0.000 claims description 16
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims description 16
- 229920005591 polysilicon Polymers 0.000 claims description 16
- 229910021332 silicide Inorganic materials 0.000 claims description 10
- FVBUAEGBCNSCDD-UHFFFAOYSA-N silicide(4-) Chemical compound [Si-4] FVBUAEGBCNSCDD-UHFFFAOYSA-N 0.000 claims description 10
- 239000012212 insulator Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- ZXEYZECDXFPJRJ-UHFFFAOYSA-N $l^{3}-silane;platinum Chemical compound [SiH3].[Pt] ZXEYZECDXFPJRJ-UHFFFAOYSA-N 0.000 claims description 4
- 229910000577 Silicon-germanium Inorganic materials 0.000 claims description 4
- 229910021339 platinum silicide Inorganic materials 0.000 claims description 4
- 229910052691 Erbium Inorganic materials 0.000 claims description 3
- UYAHIZSMUZPPFV-UHFFFAOYSA-N erbium Chemical compound [Er] UYAHIZSMUZPPFV-UHFFFAOYSA-N 0.000 claims description 3
- CKSRCDNUMJATGA-UHFFFAOYSA-N germanium platinum Chemical compound [Ge].[Pt] CKSRCDNUMJATGA-UHFFFAOYSA-N 0.000 claims description 3
- 239000010410 layer Substances 0.000 description 79
- 125000006850 spacer group Chemical group 0.000 description 35
- 239000011241 protective layer Substances 0.000 description 26
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 22
- 229910052581 Si3N4 Inorganic materials 0.000 description 21
- 238000004519 manufacturing process Methods 0.000 description 17
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 16
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 16
- 238000009413 insulation Methods 0.000 description 14
- 229910052814 silicon oxide Inorganic materials 0.000 description 12
- 238000002513 implantation Methods 0.000 description 10
- 238000005530 etching Methods 0.000 description 8
- 229920002120 photoresistant polymer Polymers 0.000 description 8
- 238000000151 deposition Methods 0.000 description 7
- 230000008021 deposition Effects 0.000 description 7
- 238000011161 development Methods 0.000 description 6
- 230000018109 developmental process Effects 0.000 description 6
- 150000004767 nitrides Chemical class 0.000 description 6
- 238000001312 dry etching Methods 0.000 description 5
- 239000000377 silicon dioxide Substances 0.000 description 5
- 238000005229 chemical vapour deposition Methods 0.000 description 4
- 229910052681 coesite Inorganic materials 0.000 description 4
- 229910052906 cristobalite Inorganic materials 0.000 description 4
- IHQKEDIOMGYHEB-UHFFFAOYSA-M sodium dimethylarsinate Chemical class [Na+].C[As](C)([O-])=O IHQKEDIOMGYHEB-UHFFFAOYSA-M 0.000 description 4
- 229910052682 stishovite Inorganic materials 0.000 description 4
- 229910052905 tridymite Inorganic materials 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical group [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- 238000005538 encapsulation Methods 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical group [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000002800 charge carrier Substances 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000000609 electron-beam lithography Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000407 epitaxy Methods 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000002210 silicon-based material Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- WQJQOUPTWCFRMM-UHFFFAOYSA-N tungsten disilicide Chemical compound [Si]#[W]#[Si] WQJQOUPTWCFRMM-UHFFFAOYSA-N 0.000 description 1
- 229910021342 tungsten silicide Inorganic materials 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
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
- H01L29/785—Field effect transistors with field effect produced by an insulated gate having a channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
-
- 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
- H01L29/66787—Unipolar field-effect transistors with an insulated gate, i.e. MISFET with a gate at the side of the channel
- H01L29/66795—Unipolar field-effect transistors with an insulated gate, i.e. MISFET with a gate at the side of the channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
Definitions
- the present invention relates to a fin field-effect transistor and a method for fabricating a fin field-effect transistor.
- FIG. 2 shows such a fin field-effect transistor 200 having a silicon substrate 201 and an oxide layer 202 made of silicon oxide SiO 2 on the silicon substrate 201 .
- a fin 203 made of silicon is provided on a part of the oxide layer 202 .
- a gate 204 of the resulting fin field-effect transistor 200 is arranged above a part of the fin 203 and along the entire height of the part of the fin 203 .
- the channel region, not visible in FIG. 2 , of the fin 203 can be inverted by charge carriers with the aid of the gate 204 extending along the sidewalls 205 of the fin 203 .
- the fin 203 which is also referred to as a Mesa, has on its end sections a source region 206 and a drain region 207 .
- the fin field-effect transistor 200 described in Hisamoto 1990 there is no self-aligned spacer technology for the LDD implantation or HDD implantation, in order that the fin 203 is not highly doped with doping atoms in the source region 206 and in the drain region 207 until after the application of the gate 204 , and that an overlapping of the gate 204 and the source region 206 or the drain region 207 , and a disadvantageous control response, associated therewith in turn, of the fin field-effect transistor 200 is avoided.
- oxide spacers 208 which prevent a doping of the fin 203 by implantation via the sidewalls 205 .
- the channel region that is not protected by oxide spacers 208 is provided with doping atoms.
- doping atoms pass laterally into the channel region after their implantation.
- short channel lengths such as occur in the case of the known fin field-effect transistor 200 —such underdiffusion has substantial negative effects on the control response of the fin field-effect transistor 200 .
- Hisamoto 1998 a fin field-effect transistor in the case of which the silicon fin is fed through in the horizontal direction by the electric current to be controlled.
- the highly doped source/drain regions are already present when the gate oxide made of silicon dioxide is grown on. This leads to a substantial running of the dopant and to undesired series resistances, particularly in the case of a very short channel.
- U.S. Pat. No. 6,252,284 B1 describes a planarized fin field-effect transistor in the case of which a spacer is arranged as electrical insulation layer between source and gate and between drain and gate, respectively, in each case between source and gate and between drain and gate.
- U.S. Pat. No. 5,300,455 describes a method for fabricating an electrically conductive diffusion barrier at the metal/silicon interface of a MOS field-effect transistor.
- U.S. Pat. No. 6,207,511 B1 describes a transistor having one or more strip channels and in the case of which the current flow takes place in the lateral direction between source and drain.
- the gate is located at the sidewalls and, if required, on the strip channel or channels.
- U.S. Pat. No. 4,996,574 describes a MIS transistor structure for increasing the conductivity between source and drain.
- the present invention is based on the problem of specifying a fin field-effect transistor in which underdiffusion in the channel region below the gate in the context of implantation with doping atoms is avoided, and in which running of doping atoms is avoided and series resistances caused thereby are prevented.
- the present invention is based on the problem of specifying a method for fabricating such a fin field-effect transistor.
- a fin field-effect transistor should generally be understood to mean a field-effect transistor whose channel region is of fin-shaped construction and constructed in a vertically projecting fashion—also in an uncovered manner, or above an insulator layer, for example an oxide layer.
- the fin field-effect transistor has a gate which extends partly above a vertically projecting structure and along its sidewalls.
- a fin field-effect transistor has a substrate, a fin above the substrate, and also a drain region and a source region outside the fin above the substrate.
- the fin does not contain the source region and the drain region, as it does in known fin field-effect transistor arrangements.
- the fin serves only as a channel between source region and drain region.
- a diffusion barrier is arranged in each case between the drain region and the fin and between the source region and the fin.
- a further fin field-effect transistor according to the present invention which optionally has a diffusion barrier in the same way as the previously described fin field-effect transistor, has a substrate, a fin above the substrate, and a drain region and a source region outside the fin above the substrate with the fin serving as a channel between the source region and the drain region.
- the drain region and the source region are formed from a material with metallic conductivity in electrical terms, a Schottky barrier being formed between the drain region and the fin and between the source region and the fin.
- the material with metallic conductivity may be platinum silicide, platinum germanium silicide or erbium silicide. It is preferred to use platinum silicide or platinum germanium silicide as material with metallic conductivity in a p-channel MOS fin field-effect transistor, and erbium silicide as material with metallic conductivity in an n-channel MOS fin field-effect transistor.
- a fin is formed above a substrate.
- a gate layer is formed at least above a part of the fin.
- the arrangement thereby formed, if appropriate extended by a gate protective layer and a gate spacer according to one of the following advantageous developments of the present invention, is coated with an insulation layer.
- the insulation layer is removed in the region of the ends of the fin in such a way that at least a part of the two ends of the fin is uncovered.
- the regions uncovered from the insulation layer are filled at least partly with material for forming a source region and a drain region.
- the present invention specifies for the first time a fin field-effect transistor in the case of which the fabrication of the channel region and the fabrication of the source and drain regions are performed in a fashion uncoupled from one another.
- the associated fabrication methods can also be optimized separately from one another.
- the gate is fabricated above the channel before the source and drain regions are fabricated. This creates a self-aligned arrangement in the case of which the gate region cannot overlap with the source region or the drain region and thus bring about undesired coupling capacitances.
- the source region and the drain region of the fin remain freely accessible, thereby enabling exact and simple doping of the source region and of the drain region of the fin.
- the substrate may have silicon, and, as an alternative, it is also possible to provide on the substrate a further layer, for example made of silicon oxide, generally made of an oxide on which the fin and also the gate are arranged.
- the gate has polysilicon. Furthermore, the gate may also be formed by a stack of polysilicon and tungsten silicide.
- the spacer may have silicon oxide and/or silicon nitride.
- the drain region and/or the source region may have polysilicon.
- the source region may be arranged at one end of the fin, and the drain region may be arranged at the other end of the fin.
- the source region on one end face of the fin cooperates with the fin
- the drain region on the other end face of the fin cooperates with the fin, the end faces terminating the fin in its longitudinal extent.
- the source region can, however, also additionally cooperate with the fin with a part, not covered by a gate, of a broad side of the fin, and the drain region can cooperate with the fin with a further part, not covered by the gate, of a broad side of the fin, the broad sides connecting the end faces of the fin to one another.
- the area of the active connection of source and drain to the channel is thereby increased.
- the source and drain regions can directly adjoin the fin.
- the source region cooperates with the fin exclusively at one end face of the fin
- the drain region cooperates with the fin exclusively at the other end face of the fin.
- a gate and a spacer can be arranged at least above a part of the fin and in this case extend essentially along the entire height of the part of the fin.
- the gate layer can be arranged between spacers in this case.
- the gate layer can also be covered by a protective layer. If, moreover, an oxide layer and/or a nitride layer are/is provided between the fin and gate layer relative to the underside of the gate layer, the gate is encapsulated.
- the encapsulation components preferably have silicon oxide or silicon nitride. In this case, it is also possible to use both materials in layers so that one material can be etched selectively relative to the other, simplified fabrication methods thereby being possible. It is to be noted in this context that this described encapsulation can also advantageously be provided in the case of a fin field effect transistor in which the diffusion barriers are not provided.
- the gate and/or the spacers may extend essentially along the entire height of the part of the fin. Furthermore, the height of the spacer with respect to the substrate may be essentially equal to the height of the gate.
- the gate including the edge-side spacers can extend along the entire length of the fin, the spacers terminating flush with the end faces of the fin, that is to say the outer sides of these edge-side spacers lie in one plane with the end faces of the fin.
- the subsequently deposited drain and source regions can have a smaller height above the substrate surface than the insulating region. As a result, there is no need for the uncovered regions in the insulation layer to be filled up completely, and so the design height of the overall arrangement can be kept small.
- the fin of the fin field-effect transistor it is possible to apply a mask marking a fin on one silicon layer of a substrate of two silicon layers enclosing a basic oxide layer.
- the silicon material of this layer is removed in such a way that a silicon body in the form of the fin is formed on the insulation layer.
- the hard-surface mask may in this case contain silicon oxide and/or silicon nitride.
- the gate can be formed by the temporarily sequential application of a gate layer, the application of a protective layer to the gate layer, the application of a mask for the further structuring of the gate, and the removal of excess material of the gate and protective layers, in such a way that a strip-shaped stack, laid over the fin, made from a gate layer and a protective layer is formed.
- Spacers may be formed in the following steps: coating the arrangement with a spacer layer, and removing the spacer layer in such a way that the further spacer layer forms spacers at least on the sides of the gate that are still uncovered before the coating with the spacer layer.
- the spacer layer and/or the protective layer may contain silicon nitride.
- a diffusion barrier is provided, this is performed—preferably at each uncovered end face of the fin—after the application of the insulation layer and of the at least partial uncovering of the ends of the fin.
- Source and drain regions are produced by virtue of the fact that the previous arrangement of fin, gate and, if appropriate, spacers and protective layer is coated with an insulation layer, which is then removed again in the region of the ends of the fin after a masking operation marking the regions to be uncovered. These uncovered regions are then filled with a material which is already doped, or is doped after the deposition.
- At least some of the elements of the fin field-effect transistor may be formed by means of deposition.
- FIG. 1 shows a longitudinal section of an exemplary embodiment of a fin field-effect transistor in accordance with the present invention
- FIG. 2 shows an oblique view of a fin field-effect transistor in accordance with the prior art
- FIG. 3 which includes FIGS. 3 a to 3 f , shows sectional views of a fin field-effect transistor illustrating the individual method steps of a method for fabricating the fin field-effect transistor of FIG. 1 ;
- FIGS. 3 a , 3 b , 3 d and 3 f show, however, the top view, belonging to the cross section, of the fin field-effect transistor in the respective method step;
- FIG. 4 shows a top view of the geometry of masks used in fabricating the fin field-effect transistor according to FIGS. 1 and 3 ;
- FIG. 5 shows a longitudinal section of a further exemplary embodiment of a fin field-effect transistor according to the present invention.
- FIG. 1 shows a fin field-effect transistor 100 in accordance with an exemplary embodiment of the present invention, in longitudinal section.
- the section is carried out in this case longitudinally through the fin of the fin field-effect transistor, approximately along the section line A-A′, to be seen in FIG. 2 , in the middle of the fin, FIG. 2 being used in this context merely to explain the position of the section line with reference to the fin.
- the longitudinal section according to FIG. 1 is a longitudinal section through a fin field-effect transistor according to the present invention, but the fin field-effect transistor according to FIG. 2 is a known fin field-effect transistor whose longitudinal section differs substantially from the longitudinal section according to FIG. 1 .
- the fin field effect transistor 100 has a substrate 101 , on which an oxide layer 102 made of silicon oxide SiO 2 having a layer thickness of approximately 200 nm is arranged (compare FIG. 1 ).
- a fin 103 made of silicon is formed on the oxide layer 102 .
- Spacers 108 preferably made of silicon nitride Si 3 N 4 —and a gate 104 made of polysilicon are arranged between the spacers 108 above a subregion of the fin 103 .
- the gate layer may also have p+-doped SiGe.
- a nitride layer 114 preferably made of silicon nitride Si 3 N 4 —and an oxide layer 113 —preferably made of silicon oxide SiO 2 —lie arranged one above another between the gate 104 and the spacers 108 , on the one hand, and the fin 103 , on the other hand.
- the nitride layer 114 is used in order to ensure that the gate oxidization is performed only on the sidewalls of the gate 104 .
- the oxide layer 113 serves as a hard-surface mask.
- a protective layer 107 made of silicon nitride Si 3 N 4 for protecting the gate 104 is applied above the gate 104 .
- the gate arrangement 104 , 107 , 108 also extends, along its width at the fin 103 , in the vertical direction along the broad sides of the fin 103 and in the corresponding, linearly continued region on the oxide layer 102 above the substrate 101 into the plane of the drawing and out of the plane of the drawing.
- a source region 109 and a drain region 110 of the fin field-effect transistor 100 are arranged adjacent to the ends of the fin 103 and in this case on the end faces 105 of the fin 103 .
- Source region 109 , drain region 110 , fin 103 and gate arrangement 104 , 107 , 108 are arranged in this case in a cut-out of an insulation layer 115 .
- Insulation layer 115 , gate arrangement 104 , 107 , 108 and partially also source region 109 and drain region 110 are coated by a further protective layer 111 .
- Contacts 112 made of metal, preferably aluminum, serve to make electric contact with source region 109 and drain region 110 .
- Source region 109 and drain region 110 are therefore coupled to one another in a conducting fashion as a channel region via the fin 103 as a function of the control by means of the gate 104 .
- the individual method steps for fabricating the fin field-effect transistor 100 in accordance with the first exemplary embodiment in longitudinal section are explained below with reference to FIG. 3 a to FIG. 3 f .
- the associated top view of the fin field-effect transistor undergoing fabrication is also specified in this case in some sectional views characterizing method steps.
- the fin field-effect transistor 100 is designed as an SOI structure (SOI: Silicon on Insulator).
- SOI Silicon on Insulator
- the structure is constructed on the insulation layer of a wafer.
- the starting point is an SOI wafer, that is to say clearly a silicon substrate 101 in which a basic oxide layer 102 made of silicon oxide SiO 2 —also termed buried oxide—is situated interposed in the manner of a sandwich (compare FIG. 3 a ).
- a basic oxide layer 102 made of silicon oxide SiO 2 —also termed buried oxide—is situated interposed in the manner of a sandwich (compare FIG. 3 a ).
- FIG. 3 a there is already remaining on the basic oxide layer 102 only a fin 103 which has been structured from the originally present silicon layer.
- a hard-surface mask made of a nitride layer made of silicon nitride Si 3 N 4 and of an oxide layer, lying there above, made of silicon oxide SiO 2 is applied to the silicon layer. This mask serves for fabricating the fin 103 .
- this mask M 1 is to be seen in top view from FIG. 4 .
- the excess material is subsequently removed from around the hard-surface mask, preferably by means of reactive ion etching after electron beam lithography has been performed, such that the structure of the fin 103 on the basic oxide layer is maintained (see FIG. 3 a ).
- the top view in FIG. 3 a shows the fin 103 on the basic oxide layer 102 , to which the shape of the mask M 1 from FIG. 4 corresponds in top view.
- the threshold voltage of the fin field-effect transistor 100 by implanting doping atoms, for example boron atoms, into the fin 103 .
- doping atoms for example boron atoms
- the gate 104 is formed by gate oxidation and a protective layer is formed.
- a gate layer made of polysilicon and a protective layer made of silicon nitride Si 3 N 4 are deposited onto the arrangement according to FIG. 3 a by means of a CVD method.
- the resulting polysilicon layer is doped with phosphor atoms or boron atoms (in situ doped deposition).
- a mask is applied to the protective layer in order to form a strip-shaped stack structure of gate and protective layers.
- the geometrical shape of a mask in top view is shown by the mask M 2 from FIG. 4 .
- Excess material is removed after the application of the mask M 2 with the aid of a suitable structuring method.
- photoresist is applied to the silicon nitride protective layer 107 in such a way that the region which is intended to be used later as gate 104 is not etched through the photoresist in further etching steps.
- the silicon nitride protective layer 107 is then etched by means of a dry etching method, as also is the polysilicon layer 106 , forming the gate, which is not covered with photoresist.
- the etching method is terminated above the fin 103 on the oxide layer 113 and above the substrate 101 on the surface of the basic oxide layer 102 , such that oxide is not etched.
- the photoresist is subsequently removed from the silicon nitride layer 107 .
- a strip-shaped stack of gate 104 and protective layer 107 is arranged above the fin 103 and a part of the substrate 101 according to FIG. 3 b.
- the protective layer strip 107 Illustrated in the top view according to FIG. 3 b is the protective layer strip 107 below which the gate strip 104 is situated. The strip arrangement is partially guided over the fin 103 .
- the strip At one end of the strip, the latter is of widened design in order to create a suitable surface for later applying a gate contact via.
- the strip shaped stack corresponds in top view in this case once again approximately to the geometrical shape of the mask M 2 from FIG. 4 .
- Spacers are formed on both sides of the uncovered edges of the gate in a further step.
- the arrangement according to FIG. 3 b is coated with a spacer layer 108 (see FIG. 3 c ).
- the coating is performed by means of a conformal CVD deposition.
- the spacer layer 108 contains silicon nitride Si 3 N 4 .
- the spacers 108 lying on the edge sides of the gate 104 are produced by anisotropic back etching of the silicon nitride spacer layer 108 with strong overetching. Spacers on the channel fin 103 are removed by the overetching. It is possible to determine, by varying the width of the spacers 108 , to what extent the source and drain regions 109 , 110 later produced cooperate with the channel.
- FIG. 3 d shows the arrangement after these fabrication steps.
- the gate 104 is encapsulated in this case in a structure of spacers 108 and the protective layer 107 .
- FIG. 3 d shows once again the top view of the arrangement after the abovementioned fabrication steps.
- the term “encapsulated” is to be understood in this context in such a way that the gate 104 is fully covered by the spacers 108 on its side faces, and on the upper surface of the gate 104 by the protective layer 107 , such that no surface areas of the gate 104 are uncovered anymore.
- an insulation layer 115 made of silicon oxide SiO 2 is deposited onto the arrangement according to FIG. 3 d by means of a CVD method.
- a part of the silicon oxide insulation layer 115 is removed again by means of a chemical mechanical polishing method until the silicon nitride protective layer 107 is reached.
- the CMP method is stopped once the silicon nitride protective layer 107 is reached.
- a mask is arranged on the insulation layer 115 , for example in the form of photoresist.
- the geometrical shape of this mask is reproduced in top view by the mask M 3 from FIG. 4 .
- a dry etching method is used to etch silicon oxide from the insulation layer 115 down to the surface of the basic oxide layer 102 .
- the dry etching is selective with respect to silicon nitride, such that the etching process is stopped at the nitride layer 114 in the region of the fin 103 , and the nitride-containing spacers 108 and protective layer 107 are not etched away in the region of the gate arrangement.
- the ends of the fin 103 are freely accessible after this fabrication step. This is necessary in order to connect the fin 103 serving as a channel to a source region and a drain region.
- the accesses/holes, uncovered by the preceding etching operation, to the fin ends are filled at least partially with suitable material, preferably polysilicon, in order to form a source region and a drain region, a thin dielectric layer, forming a diffusion barrier, previously being applied to the uncovered accesses/holes to the fin ends, which are intended to prevent diffusion of doping atoms from the source and drain into the channel region.
- suitable material preferably polysilicon
- the resulting polysilicon layer is doped with suitable doping atoms (in-situ-doped filling).
- the polysilicon can also be applied by selective epitaxy or by CVD deposition with a subsequent CMP method and/or suitable back etching.
- the doping of the source region 109 and the drain region 110 can also be performed by subsequent n+-implantation.
- the production of the source and drain regions 109 , 110 is performed after the construction of the gate 104 above the fin 103 , and so a field-effect transistor of self-adjusted design is created in the case of which gate region and source or drain regions do not overlap and influence one another disadvantageously.
- FIG. 3 f shows an arrangement after carrying out these fabrication steps in longitudinal section and in top view.
- siliciding takes place and produces a silicide layer on the source and drain regions 109 , 110 for the purpose of reducing the contact resistance to contacts, still to be fitted, for source, gate and drain.
- Tungsten serves as actual contact material.
- Serving in this case as an adhesion layer and a diffusion barrier therefor is a double layer made of titanium and titanium nitride which is sputtered onto the source region 109 and the drain region 110 . Only then is contact made with the gate, source and drain.
- the contact vias are once again obtained with the aid of etching processes.
- a further protective layer 111 is deposited using the CVD method onto the existing arrangement for this purpose.
- a mask is applied, for example in the form of photoresist, to the further protective layer 111 .
- the geometrical shape of this mask is shown by the mask M 4 in FIG. 4 , in top view.
- the mask M 4 in this case marks the regions provided for making contact with the gate, source and drain.
- regions are etched from the further protective layer 111 by means of a dry etching method so as to create access to the source, drain and gate regions which is free and direct or indirect via the silicide layer. These accesses are then filled with metal-containing material in order to form contacts 112 .
- FIG. 1 A fin field-effect transistor according to the present invention is shown in FIG. 1 after these fabrication steps have been carried out.
- FIG. 5 shows a second exemplary embodiment of a fin field-effect transistor according to the present invention, in longitudinal section.
- This fin field-effect transistor differs from the fin field-effect transistor in accordance with FIG. 1 and FIG. 3 in that the width of the gate 104 including the spacers 108 corresponds to the length of the fin 103 .
- the source region 109 and the drain region 110 can cooperate with the fin 103 only on the end faces 105 thereof.
- the outer sides of the spacers 108 lie in a plane with the end faces 105 of the fin 103 .
- the source region 109 and the drain region 110 can also cooperate with end regions 105 of broad sides of the fin 103 , the broad sides of the fin 103 projecting from the basic oxide layer 102 and connecting the end faces 105 of the fin 103 to one another.
- the cooperation of source and drain regions 109 , 110 with the fin 103 serving as a channel can be ensured by virtue of the fact that source and drain regions 109 , 110 bear against the sides provided for the purpose on the fin 103 .
- these diffusion barriers are produced after the gate arrangement 104 , 107 , 108 has been produced, and the ends of the fin 103 have been uncovered again after the deposition of the protective layer 115 , and before these uncovered regions are once again filled with material in order to form source and drain.
- the diffusion barriers are produced in this case by thermal oxidation.
Abstract
A fin field-effect transistor has a substrate and a fin structure above the substrate, as well as a drain region and a source region outside the fin structure above the substrate. The fin structure serves as a channel between the source region and the drain region. The source and drain regions are formed once a gate has been produced.
Description
- This application is a continuation of U.S. patent application Ser. No. 10/768,971, filed on Jan. 30, 2004, which is a continuation of International Patent Application Serial No. PCT/DE02/02760, filed on Jul. 26, 2002, which published in German on Feb. 20, 2003 as WO 03/015182 A2, and which claimed priority to German Patent Application No. 101 37 217.5, filed on Jul. 30, 2001, all of which applications are incorporated herein by reference.
- The present invention relates to a fin field-effect transistor and a method for fabricating a fin field-effect transistor.
- A fin field-effect transistor and a method for fabricating such a fin field-effect transistor are described in D. Hisamoto, et al., “A Fully Depleted Lean-Channel Transistor (DELTA)—A novel vertical ultrathin SOI MOSFET,” IEEE Electron Device Letters, Volume 11, No. 1, pages 36-38, 1990 (hereinafter “Hisamoto 1990”).
FIG. 2 shows such a fin field-effect transistor 200 having asilicon substrate 201 and anoxide layer 202 made of silicon oxide SiO2 on thesilicon substrate 201. - A
fin 203 made of silicon is provided on a part of theoxide layer 202. Agate 204 of the resulting fin field-effect transistor 200 is arranged above a part of thefin 203 and along the entire height of the part of thefin 203. - In the case of the fin field-
effect transistor 200 described in Hisamoto 1990, the channel region, not visible inFIG. 2 , of thefin 203 can be inverted by charge carriers with the aid of thegate 204 extending along thesidewalls 205 of thefin 203. Thefin 203, which is also referred to as a Mesa, has on its end sections asource region 206 and adrain region 207. - In the case of the fin field-
effect transistor 200 described in Hisamoto 1990, there is no self-aligned spacer technology for the LDD implantation or HDD implantation, in order that thefin 203 is not highly doped with doping atoms in thesource region 206 and in thedrain region 207 until after the application of thegate 204, and that an overlapping of thegate 204 and thesource region 206 or thedrain region 207, and a disadvantageous control response, associated therewith in turn, of the fin field-effect transistor 200 is avoided. - In the case of the fin field-
effect transistor 200 described in Hisamoto 1990, there are firstly formed along thesidewalls 205 of the fin 203oxide spacers 208 which prevent a doping of thefin 203 by implantation via thesidewalls 205. In the case of implantation via the free fin surfaces, however, in addition to thesource region 206 and thedrain region 207, the channel region that is not protected byoxide spacers 208 is provided with doping atoms. In the case of this underdiffusion, doping atoms pass laterally into the channel region after their implantation. Particularly in the case of short channel lengths—such as occur in the case of the known fin field-effect transistor 200—such underdiffusion has substantial negative effects on the control response of the fin field-effect transistor 200. - Furthermore, there is described in D. Hisamoto, et al., “A Folded-Channel MOSFET for Deep-Sub-Tenth Micron Era, IEDM 98, pages 1032-1034, 1998 (hereinafter “Hisamoto 1998”) a fin field-effect transistor in the case of which the silicon fin is fed through in the horizontal direction by the electric current to be controlled. In the fabrication method in accordance with Hisamoto 1998, the highly doped source/drain regions are already present when the gate oxide made of silicon dioxide is grown on. This leads to a substantial running of the dopant and to undesired series resistances, particularly in the case of a very short channel.
- J. Kedzierski, et al., “Complementary Silicide Source/Drain Thin-Body MOSFETs for the 20 nm Gate Length Regime,” IEDM 2000, pages 57-60, describes a MOS field-effect transistor in the case of which the drain region and the source region are formed from platinum silicide.
- U.S. Pat. No. 6,252,284 B1 describes a planarized fin field-effect transistor in the case of which a spacer is arranged as electrical insulation layer between source and gate and between drain and gate, respectively, in each case between source and gate and between drain and gate.
- Furthermore, U.S. Pat. No. 5,300,455 describes a method for fabricating an electrically conductive diffusion barrier at the metal/silicon interface of a MOS field-effect transistor.
- U.S. Pat. No. 6,207,511 B1 describes a transistor having one or more strip channels and in the case of which the current flow takes place in the lateral direction between source and drain. The gate is located at the sidewalls and, if required, on the strip channel or channels.
- U.S. Pat. No. 5,623,155 describes an SOI-MOS field-effect transistor.
- U.S. Pat. No. 4,996,574 describes a MIS transistor structure for increasing the conductivity between source and drain.
- The present invention is based on the problem of specifying a fin field-effect transistor in which underdiffusion in the channel region below the gate in the context of implantation with doping atoms is avoided, and in which running of doping atoms is avoided and series resistances caused thereby are prevented.
- Furthermore, the present invention is based on the problem of specifying a method for fabricating such a fin field-effect transistor.
- The problems are solved by the fin field-effect transistor and by the method for fabricating the fin field-effect transistor having the features in accordance with the claims of the present application.
- In the context of the present invention, a fin field-effect transistor should generally be understood to mean a field-effect transistor whose channel region is of fin-shaped construction and constructed in a vertically projecting fashion—also in an uncovered manner, or above an insulator layer, for example an oxide layer. The fin field-effect transistor has a gate which extends partly above a vertically projecting structure and along its sidewalls.
- A fin field-effect transistor according to the present invention has a substrate, a fin above the substrate, and also a drain region and a source region outside the fin above the substrate. In this case, the fin does not contain the source region and the drain region, as it does in known fin field-effect transistor arrangements. The fin serves only as a channel between source region and drain region. A diffusion barrier is arranged in each case between the drain region and the fin and between the source region and the fin.
- A further fin field-effect transistor according to the present invention, which optionally has a diffusion barrier in the same way as the previously described fin field-effect transistor, has a substrate, a fin above the substrate, and a drain region and a source region outside the fin above the substrate with the fin serving as a channel between the source region and the drain region.
- The drain region and the source region are formed from a material with metallic conductivity in electrical terms, a Schottky barrier being formed between the drain region and the fin and between the source region and the fin.
- The material with metallic conductivity may be platinum silicide, platinum germanium silicide or erbium silicide. It is preferred to use platinum silicide or platinum germanium silicide as material with metallic conductivity in a p-channel MOS fin field-effect transistor, and erbium silicide as material with metallic conductivity in an n-channel MOS fin field-effect transistor.
- In an exemplary method according to the present invention for fabricating a fin field-effect transistor, a fin is formed above a substrate. A gate layer is formed at least above a part of the fin. The arrangement thereby formed, if appropriate extended by a gate protective layer and a gate spacer according to one of the following advantageous developments of the present invention, is coated with an insulation layer. Subsequently, the insulation layer is removed in the region of the ends of the fin in such a way that at least a part of the two ends of the fin is uncovered. The regions uncovered from the insulation layer are filled at least partly with material for forming a source region and a drain region.
- The present invention specifies for the first time a fin field-effect transistor in the case of which the fabrication of the channel region and the fabrication of the source and drain regions are performed in a fashion uncoupled from one another. The associated fabrication methods can also be optimized separately from one another.
- In this case, the gate is fabricated above the channel before the source and drain regions are fabricated. This creates a self-aligned arrangement in the case of which the gate region cannot overlap with the source region or the drain region and thus bring about undesired coupling capacitances.
- Moreover, the running of doping atoms owing to the production, occurring after the fabrication of the gate, of the highly doped source and drain regions is avoided in the case of the present invention, as a result of which no undesired series resistances are formed.
- Moreover, in the case of a fin field-effect transistor according to the present invention, the source region and the drain region of the fin remain freely accessible, thereby enabling exact and simple doping of the source region and of the drain region of the fin.
- Preferred developments of the invention emerge from the dependent claims.
- The refinements described below refer both to the fin field-effect transistor and to methods for fabricating the fin field-effect transistor.
- The substrate may have silicon, and, as an alternative, it is also possible to provide on the substrate a further layer, for example made of silicon oxide, generally made of an oxide on which the fin and also the gate are arranged.
- In accordance with a refinement of the present invention, the gate has polysilicon. Furthermore, the gate may also be formed by a stack of polysilicon and tungsten silicide.
- The spacer may have silicon oxide and/or silicon nitride.
- The drain region and/or the source region may have polysilicon.
- The source region may be arranged at one end of the fin, and the drain region may be arranged at the other end of the fin.
- In a further advantageous development of the present invention, the source region on one end face of the fin cooperates with the fin, and the drain region on the other end face of the fin cooperates with the fin, the end faces terminating the fin in its longitudinal extent.
- The source region can, however, also additionally cooperate with the fin with a part, not covered by a gate, of a broad side of the fin, and the drain region can cooperate with the fin with a further part, not covered by the gate, of a broad side of the fin, the broad sides connecting the end faces of the fin to one another. The area of the active connection of source and drain to the channel is thereby increased. In this case the source and drain regions can directly adjoin the fin.
- In a further advantageous development of the present invention, the source region cooperates with the fin exclusively at one end face of the fin, and the drain region cooperates with the fin exclusively at the other end face of the fin. This refinement is particularly advantageous whenever the aim is to arrange one diffusion barrier each between drain region and fin, and between source region and fin, which diffusion barrier is intended to prevent indiffusion of the dopant for the source and drain.
- A gate and a spacer can be arranged at least above a part of the fin and in this case extend essentially along the entire height of the part of the fin. The gate layer can be arranged between spacers in this case. The gate layer can also be covered by a protective layer. If, moreover, an oxide layer and/or a nitride layer are/is provided between the fin and gate layer relative to the underside of the gate layer, the gate is encapsulated. The encapsulation components preferably have silicon oxide or silicon nitride. In this case, it is also possible to use both materials in layers so that one material can be etched selectively relative to the other, simplified fabrication methods thereby being possible. It is to be noted in this context that this described encapsulation can also advantageously be provided in the case of a fin field effect transistor in which the diffusion barriers are not provided.
- The gate and/or the spacers may extend essentially along the entire height of the part of the fin. Furthermore, the height of the spacer with respect to the substrate may be essentially equal to the height of the gate.
- Underdiffusion during implantation of the source region and the drain region of the fin field-effect transistor is practically completely avoided by virtue of this refinement.
- The gate including the edge-side spacers can extend along the entire length of the fin, the spacers terminating flush with the end faces of the fin, that is to say the outer sides of these edge-side spacers lie in one plane with the end faces of the fin. In the case of this advantageous development, it is then only the end faces of the fin that are freely accessible to coupling with the subsequently inserted source and drain regions, it being possible here to provide the dielectric barriers, with their previously described advantages, in a particularly simple way.
- The subsequently deposited drain and source regions can have a smaller height above the substrate surface than the insulating region. As a result, there is no need for the uncovered regions in the insulation layer to be filled up completely, and so the design height of the overall arrangement can be kept small.
- In order to form the fin of the fin field-effect transistor, it is possible to apply a mask marking a fin on one silicon layer of a substrate of two silicon layers enclosing a basic oxide layer. The silicon material of this layer is removed in such a way that a silicon body in the form of the fin is formed on the insulation layer. The hard-surface mask may in this case contain silicon oxide and/or silicon nitride.
- The gate can be formed by the temporarily sequential application of a gate layer, the application of a protective layer to the gate layer, the application of a mask for the further structuring of the gate, and the removal of excess material of the gate and protective layers, in such a way that a strip-shaped stack, laid over the fin, made from a gate layer and a protective layer is formed.
- Spacers may be formed in the following steps: coating the arrangement with a spacer layer, and removing the spacer layer in such a way that the further spacer layer forms spacers at least on the sides of the gate that are still uncovered before the coating with the spacer layer. The spacer layer and/or the protective layer may contain silicon nitride.
- If a diffusion barrier is provided, this is performed—preferably at each uncovered end face of the fin—after the application of the insulation layer and of the at least partial uncovering of the ends of the fin.
- Source and drain regions are produced by virtue of the fact that the previous arrangement of fin, gate and, if appropriate, spacers and protective layer is coated with an insulation layer, which is then removed again in the region of the ends of the fin after a masking operation marking the regions to be uncovered. These uncovered regions are then filled with a material which is already doped, or is doped after the deposition.
- At least some of the elements of the fin field-effect transistor may be formed by means of deposition. Thus, in accordance with this development, it is possible to use a conventional semiconductor processing technique, thus enabling the fabrication method to be implemented in a simple and cost-effective way.
- However, in addition to CVD methods it is also possible to use sputtering or vapor deposition methods to arrange layers or materials in the proposed application process.
- Exemplary embodiments of the present invention are illustrated in the figures and are explained in more detail below.
-
FIG. 1 shows a longitudinal section of an exemplary embodiment of a fin field-effect transistor in accordance with the present invention; -
FIG. 2 shows an oblique view of a fin field-effect transistor in accordance with the prior art; -
FIG. 3 , which includesFIGS. 3 a to 3 f, shows sectional views of a fin field-effect transistor illustrating the individual method steps of a method for fabricating the fin field-effect transistor ofFIG. 1 ;FIGS. 3 a, 3 b, 3 d and 3 f show, however, the top view, belonging to the cross section, of the fin field-effect transistor in the respective method step; -
FIG. 4 shows a top view of the geometry of masks used in fabricating the fin field-effect transistor according toFIGS. 1 and 3 ; and -
FIG. 5 shows a longitudinal section of a further exemplary embodiment of a fin field-effect transistor according to the present invention. -
FIG. 1 shows a fin field-effect transistor 100 in accordance with an exemplary embodiment of the present invention, in longitudinal section. The section is carried out in this case longitudinally through the fin of the fin field-effect transistor, approximately along the section line A-A′, to be seen inFIG. 2 , in the middle of the fin,FIG. 2 being used in this context merely to explain the position of the section line with reference to the fin. Otherwise, however, the longitudinal section according toFIG. 1 is a longitudinal section through a fin field-effect transistor according to the present invention, but the fin field-effect transistor according toFIG. 2 is a known fin field-effect transistor whose longitudinal section differs substantially from the longitudinal section according toFIG. 1 . - The fin
field effect transistor 100 has asubstrate 101, on which anoxide layer 102 made of silicon oxide SiO2 having a layer thickness of approximately 200 nm is arranged (compareFIG. 1 ). - A
fin 103 made of silicon is formed on theoxide layer 102.Spacers 108—preferably made of silicon nitride Si3N4—and agate 104 made of polysilicon are arranged between thespacers 108 above a subregion of thefin 103. The gate layer may also have p+-doped SiGe. - A
nitride layer 114—preferably made of silicon nitride Si3N4—and anoxide layer 113—preferably made of silicon oxide SiO2—lie arranged one above another between thegate 104 and thespacers 108, on the one hand, and thefin 103, on the other hand. Thenitride layer 114 is used in order to ensure that the gate oxidization is performed only on the sidewalls of thegate 104. Theoxide layer 113 serves as a hard-surface mask. - A
protective layer 107 made of silicon nitride Si3N4 for protecting thegate 104 is applied above thegate 104. In addition—which cannot be seen in the longitudinal section in accordance withFIG. 1 —thegate arrangement fin 103, in the vertical direction along the broad sides of thefin 103 and in the corresponding, linearly continued region on theoxide layer 102 above thesubstrate 101 into the plane of the drawing and out of the plane of the drawing. - A
source region 109 and adrain region 110 of the fin field-effect transistor 100 are arranged adjacent to the ends of thefin 103 and in this case on the end faces 105 of thefin 103. -
Source region 109,drain region 110,fin 103 andgate arrangement insulation layer 115. -
Insulation layer 115,gate arrangement region 109 and drainregion 110 are coated by a furtherprotective layer 111. -
Contacts 112 made of metal, preferably aluminum, serve to make electric contact withsource region 109 and drainregion 110. -
Source region 109 and drainregion 110 are therefore coupled to one another in a conducting fashion as a channel region via thefin 103 as a function of the control by means of thegate 104. - Hereinafter, the same reference symbols are used for identical elements in different drawings.
- The individual method steps for fabricating the fin field-
effect transistor 100 in accordance with the first exemplary embodiment in longitudinal section are explained below with reference toFIG. 3 a toFIG. 3 f. To improve the illustration, the associated top view of the fin field-effect transistor undergoing fabrication is also specified in this case in some sectional views characterizing method steps. - The fin field-
effect transistor 100 is designed as an SOI structure (SOI: Silicon on Insulator). In this case, the structure is constructed on the insulation layer of a wafer. - The starting point is an SOI wafer, that is to say clearly a
silicon substrate 101 in which abasic oxide layer 102 made of silicon oxide SiO2—also termed buried oxide—is situated interposed in the manner of a sandwich (compareFIG. 3 a). InFIG. 3 a, there is already remaining on thebasic oxide layer 102 only afin 103 which has been structured from the originally present silicon layer. - In order to fabricate the
fin 103, a hard-surface mask made of a nitride layer made of silicon nitride Si3N4 and of an oxide layer, lying there above, made of silicon oxide SiO2 is applied to the silicon layer. This mask serves for fabricating thefin 103. - The geometrical design of this mask M1 is to be seen in top view from
FIG. 4 . The excess material is subsequently removed from around the hard-surface mask, preferably by means of reactive ion etching after electron beam lithography has been performed, such that the structure of thefin 103 on the basic oxide layer is maintained (seeFIG. 3 a). - It is thereby possible subsequently to apply photoresist to the silicon layer formed, and the silicon which is not covered with photoresist can be etched by means of a dry etching method. The etching method is stopped as soon as the surface of the
basic oxide layer 102 is reached. - The top view in
FIG. 3 a shows thefin 103 on thebasic oxide layer 102, to which the shape of the mask M1 fromFIG. 4 corresponds in top view. - It is subsequently possible as an option to set the threshold voltage of the fin field-
effect transistor 100 by implanting doping atoms, for example boron atoms, into thefin 103. In the case of a completely depleted transistor, this channeled implantation can also be omitted in the course of the method. - In further steps, the
gate 104 is formed by gate oxidation and a protective layer is formed. For this purpose, a gate layer made of polysilicon and a protective layer made of silicon nitride Si3N4 are deposited onto the arrangement according toFIG. 3 a by means of a CVD method. During the deposition of the polysilicon, the resulting polysilicon layer is doped with phosphor atoms or boron atoms (in situ doped deposition). - Subsequently, a mask is applied to the protective layer in order to form a strip-shaped stack structure of gate and protective layers. The geometrical shape of a mask in top view is shown by the mask M2 from
FIG. 4 . Excess material is removed after the application of the mask M2 with the aid of a suitable structuring method. For example, photoresist is applied to the silicon nitrideprotective layer 107 in such a way that the region which is intended to be used later asgate 104 is not etched through the photoresist in further etching steps. In a subsequent step, the silicon nitrideprotective layer 107 is then etched by means of a dry etching method, as also is thepolysilicon layer 106, forming the gate, which is not covered with photoresist. - The etching method is terminated above the
fin 103 on theoxide layer 113 and above thesubstrate 101 on the surface of thebasic oxide layer 102, such that oxide is not etched. - The photoresist is subsequently removed from the
silicon nitride layer 107. - After these method steps, a strip-shaped stack of
gate 104 andprotective layer 107 is arranged above thefin 103 and a part of thesubstrate 101 according toFIG. 3 b. - Illustrated in the top view according to
FIG. 3 b is theprotective layer strip 107 below which thegate strip 104 is situated. The strip arrangement is partially guided over thefin 103. - At one end of the strip, the latter is of widened design in order to create a suitable surface for later applying a gate contact via. The strip shaped stack corresponds in top view in this case once again approximately to the geometrical shape of the mask M2 from
FIG. 4 . - Spacers are formed on both sides of the uncovered edges of the gate in a further step. For this purpose, the arrangement according to
FIG. 3 b is coated with a spacer layer 108 (seeFIG. 3 c). The coating is performed by means of a conformal CVD deposition. In this case, thespacer layer 108 contains silicon nitride Si3N4. - The
spacers 108 lying on the edge sides of thegate 104 are produced by anisotropic back etching of the siliconnitride spacer layer 108 with strong overetching. Spacers on thechannel fin 103 are removed by the overetching. It is possible to determine, by varying the width of thespacers 108, to what extent the source and drainregions -
FIG. 3 d shows the arrangement after these fabrication steps. Thegate 104 is encapsulated in this case in a structure ofspacers 108 and theprotective layer 107. Moreover,FIG. 3 d shows once again the top view of the arrangement after the abovementioned fabrication steps. The term “encapsulated” is to be understood in this context in such a way that thegate 104 is fully covered by thespacers 108 on its side faces, and on the upper surface of thegate 104 by theprotective layer 107, such that no surface areas of thegate 104 are uncovered anymore. - Subsequently, an
insulation layer 115 made of silicon oxide SiO2 is deposited onto the arrangement according toFIG. 3 d by means of a CVD method. - Subsequently, a part of the silicon
oxide insulation layer 115 is removed again by means of a chemical mechanical polishing method until the silicon nitrideprotective layer 107 is reached. The CMP method is stopped once the silicon nitrideprotective layer 107 is reached. - The arrangement according to this fabrication step is shown in longitudinal section in
FIG. 3 e. - Subsequently, a mask is arranged on the
insulation layer 115, for example in the form of photoresist. The geometrical shape of this mask is reproduced in top view by the mask M3 fromFIG. 4 . - Subsequently, a dry etching method is used to etch silicon oxide from the
insulation layer 115 down to the surface of thebasic oxide layer 102. The dry etching is selective with respect to silicon nitride, such that the etching process is stopped at thenitride layer 114 in the region of thefin 103, and the nitride-containingspacers 108 andprotective layer 107 are not etched away in the region of the gate arrangement. - In accordance with
FIG. 3 f, the ends of thefin 103 are freely accessible after this fabrication step. This is necessary in order to connect thefin 103 serving as a channel to a source region and a drain region. - The accesses/holes, uncovered by the preceding etching operation, to the fin ends are filled at least partially with suitable material, preferably polysilicon, in order to form a source region and a drain region, a thin dielectric layer, forming a diffusion barrier, previously being applied to the uncovered accesses/holes to the fin ends, which are intended to prevent diffusion of doping atoms from the source and drain into the channel region. The polysilicon is applied to the diffusion barrier layer.
- During the filling of the accesses with polysilicon, the resulting polysilicon layer is doped with suitable doping atoms (in-situ-doped filling). However, the polysilicon can also be applied by selective epitaxy or by CVD deposition with a subsequent CMP method and/or suitable back etching.
- As an alternative to the in-situ doping, the doping of the
source region 109 and thedrain region 110 can also be performed by subsequent n+-implantation. - In any case, the production of the source and drain
regions gate 104 above thefin 103, and so a field-effect transistor of self-adjusted design is created in the case of which gate region and source or drain regions do not overlap and influence one another disadvantageously. - An undesired implantation of atoms into the channel region is also avoided with this fabrication method.
-
FIG. 3 f shows an arrangement after carrying out these fabrication steps in longitudinal section and in top view. - In final standard semiconductor process steps, siliciding takes place and produces a silicide layer on the source and drain
regions source region 109 and thedrain region 110. Only then is contact made with the gate, source and drain. - The contact vias are once again obtained with the aid of etching processes. Firstly, a further
protective layer 111 is deposited using the CVD method onto the existing arrangement for this purpose. Subsequently, a mask is applied, for example in the form of photoresist, to the furtherprotective layer 111. The geometrical shape of this mask is shown by the mask M4 inFIG. 4 , in top view. The mask M4 in this case marks the regions provided for making contact with the gate, source and drain. - Subsequently, regions are etched from the further
protective layer 111 by means of a dry etching method so as to create access to the source, drain and gate regions which is free and direct or indirect via the silicide layer. These accesses are then filled with metal-containing material in order to formcontacts 112. - A fin field-effect transistor according to the present invention is shown in
FIG. 1 after these fabrication steps have been carried out. -
FIG. 5 shows a second exemplary embodiment of a fin field-effect transistor according to the present invention, in longitudinal section. - This fin field-effect transistor differs from the fin field-effect transistor in accordance with
FIG. 1 andFIG. 3 in that the width of thegate 104 including thespacers 108 corresponds to the length of thefin 103. - The result of this, firstly, is that the
source region 109 and thedrain region 110 can cooperate with thefin 103 only on the end faces 105 thereof. The outer sides of thespacers 108 lie in a plane with the end faces 105 of thefin 103. By contrast, in the case of the exemplary embodiment according toFIG. 1 andFIG. 3 , thesource region 109 and thedrain region 110 can also cooperate withend regions 105 of broad sides of thefin 103, the broad sides of thefin 103 projecting from thebasic oxide layer 102 and connecting the end faces 105 of thefin 103 to one another. - In the exemplary embodiments shown, the cooperation of source and drain
regions fin 103 serving as a channel can be ensured by virtue of the fact that source and drainregions fin 103. - In the exemplary embodiment according to
FIG. 5 , however, there are set up according to the present invention between the end faces 105 of thefin 103 and thesource region 109 and thedrain region 110diffusion barriers 106 which are intended to prevent diffusion of doping atoms from the source and drain into the channel region. - In an advantageous way, these diffusion barriers are produced after the
gate arrangement fin 103 have been uncovered again after the deposition of theprotective layer 115, and before these uncovered regions are once again filled with material in order to form source and drain. The diffusion barriers are produced in this case by thermal oxidation.
Claims (20)
1. An integrated circuit comprising:
an insulating layer;
a first source/drain portion and a second source/drain portion; and
a channel disposed between the first and second source/drain portions,
wherein the channel is disposed in a fin disposed over the insulating layer, and wherein an upper surface of the first and second source/drain portions is disposed at a higher height than an upper surface of the channel, the height being measured with respect to an upper surface of the insulating layer.
2. The integrated circuit of claim 1 , wherein at least one of the first and second source/drain portions comprises polysilicon.
3. The integrated circuit of claim 1 , wherein at least one of the first and second source/drain portions comprises a silicide containing a metal.
4. The integrated circuit of claim 1 , wherein the fin includes silicon.
5. The integrated circuit of claim 1 , further comprising a substrate beneath the insulating layer.
6. An integrated circuit comprising:
an insulating layer;
a first source/drain portion and a second source/drain portion;
a channel disposed between the first and second source/drain portions;
a gate electrode adjacent the channel; and
an intermediate layer disposed between the channel and the first and second source/drain portions, respectively,
wherein the channel is disposed in a fin disposed over the insulating layer, and wherein the first and second source/drain portions are self-aligned with respect to the gate electrode.
7. The integrated circuit of claim 6 , wherein at least one of the first and second source/drain portions comprises polysilicon.
8. The integrated circuit of claim 6 , wherein at least one of the first and second source/drain portions comprises a silicide containing a metal.
9. The integrated circuit of claim 6 , wherein the fin includes silicon.
10. An integrated circuit comprising:
an insulating layer;
a first source/drain portion and a second source/drain portion; and
a channel disposed between the first and second source/drain portions,
wherein the channel is disposed in a fin disposed over the insulating layer, and wherein a width of the first or second source/drain portion is larger than a width of the fin, the widths being measured perpendicularly with respect to a line connecting the first and second source/drain portions.
11. The integrated circuit of claim 10 , further comprising an intermediate layer disposed between the channel and the first and second source/drain portions, respectively.
12. The integrated circuit of claim 10 , wherein at least one of the first and second source/drain portions comprises polysilicon.
13. The integrated circuit of claim 10 , wherein at least one of the first and second source/drain portions comprises a silicide containing a metal.
14. The integrated circuit of claim 10 , wherein the fin includes silicon.
15. An integrated circuit comprising:
an insulator layer;
a fin disposed over the insulator layer;
a first source/drain region and a second source/drain region disposed outside the fin over the insulator layer, the first and/or second source/drain region being formed from a material with metallic conductivity;
a Schottky barrier disposed between the first source/drain region and the fin and between the second source/drain region and the fin; and
a gate disposed adjacent a channel portion of the fin, the channel portion providing a current path between the first source/drain region and the second source/drain region.
16. The integrated circuit of claim 15 , further comprising a diffusion barrier disposed between the first source/drain region and the fin and between the second source/drain region and the fin.
17. The integrated circuit of claim 15 , wherein the gate extends substantially along the entire height of at least a part of the fin.
18. The integrated circuit of claim 15 , further comprising a substrate, wherein the insulator layer overlies the substrate.
19. The integrated circuit of claim 15 , wherein the material with metallic conductivity comprises a silicide.
20. The integrated circuit of claim 19 , wherein the material with metallic conductivity comprises a material selected from the group consisting of platinum silicide, platinum germanium silicide and erbium silicide.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/833,080 US20080035997A1 (en) | 2001-07-30 | 2007-08-02 | Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10137217A DE10137217A1 (en) | 2001-07-30 | 2001-07-30 | Bridge field effect transistor and method for producing a bridge field effect transistor |
DE10137217.5 | 2001-07-30 | ||
PCT/DE2002/002760 WO2003015182A2 (en) | 2001-07-30 | 2002-07-26 | Fin field effect transistor and method for producing a fin field effect transistor |
US10/768,971 US7265424B2 (en) | 2001-07-30 | 2004-01-30 | Fin Field-effect transistor and method for producing a fin field effect-transistor |
US11/833,080 US20080035997A1 (en) | 2001-07-30 | 2007-08-02 | Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/768,971 Continuation US7265424B2 (en) | 2001-07-30 | 2004-01-30 | Fin Field-effect transistor and method for producing a fin field effect-transistor |
Publications (1)
Publication Number | Publication Date |
---|---|
US20080035997A1 true US20080035997A1 (en) | 2008-02-14 |
Family
ID=7693676
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/768,971 Expired - Fee Related US7265424B2 (en) | 2001-07-30 | 2004-01-30 | Fin Field-effect transistor and method for producing a fin field effect-transistor |
US11/833,080 Abandoned US20080035997A1 (en) | 2001-07-30 | 2007-08-02 | Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/768,971 Expired - Fee Related US7265424B2 (en) | 2001-07-30 | 2004-01-30 | Fin Field-effect transistor and method for producing a fin field effect-transistor |
Country Status (5)
Country | Link |
---|---|
US (2) | US7265424B2 (en) |
EP (1) | EP1412986A2 (en) |
DE (1) | DE10137217A1 (en) |
TW (1) | TW554537B (en) |
WO (1) | WO2003015182A2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070152272A1 (en) * | 2005-12-29 | 2007-07-05 | Jeong Ho Park | Method for fabricating a transistor using a soi wafer |
US20110068404A1 (en) * | 2009-09-18 | 2011-03-24 | Kabushiki Kaisha Toshiba | Semiconductor device and method for manufacturing the same |
US20120208329A1 (en) * | 2009-09-21 | 2012-08-16 | International Business Machines Corporation | Integrated circuit device with series-connected field effect transistors and integrated voltage equalization and method of forming the device |
WO2014159481A1 (en) * | 2013-03-14 | 2014-10-02 | International Business Machines Corporation | Partially isolated fin-shaped field effect transistors |
US20150014773A1 (en) * | 2013-07-12 | 2015-01-15 | International Business Machines Corporation | Partial FIN On Oxide For Improved Electrical Isolation Of Raised Active Regions |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10137217A1 (en) * | 2001-07-30 | 2003-02-27 | Infineon Technologies Ag | Bridge field effect transistor and method for producing a bridge field effect transistor |
US6686231B1 (en) * | 2002-12-06 | 2004-02-03 | Advanced Micro Devices, Inc. | Damascene gate process with sacrificial oxide in semiconductor devices |
US6864164B1 (en) | 2002-12-17 | 2005-03-08 | Advanced Micro Devices, Inc. | Finfet gate formation using reverse trim of dummy gate |
US6855582B1 (en) | 2003-06-12 | 2005-02-15 | Advanced Micro Devices, Inc. | FinFET gate formation using reverse trim and oxide polish |
US7041542B2 (en) | 2004-01-12 | 2006-05-09 | Advanced Micro Devices, Inc. | Damascene tri-gate FinFET |
US7084018B1 (en) | 2004-05-05 | 2006-08-01 | Advanced Micro Devices, Inc. | Sacrificial oxide for minimizing box undercut in damascene FinFET |
TWI277210B (en) * | 2004-10-26 | 2007-03-21 | Nanya Technology Corp | FinFET transistor process |
US7858481B2 (en) | 2005-06-15 | 2010-12-28 | Intel Corporation | Method for fabricating transistor with thinned channel |
TWI283482B (en) * | 2006-06-05 | 2007-07-01 | Promos Technologies Inc | Multi-fin field effect transistor and fabricating method thereof |
US7646046B2 (en) * | 2006-11-14 | 2010-01-12 | Infineon Technologies Ag | Field effect transistor with a fin structure |
US7838948B2 (en) * | 2007-01-30 | 2010-11-23 | Infineon Technologies Ag | Fin interconnects for multigate FET circuit blocks |
US8682116B2 (en) * | 2007-08-08 | 2014-03-25 | Infineon Technologies Ag | Integrated circuit including non-planar structure and waveguide |
DE102008059500B4 (en) * | 2008-11-28 | 2010-08-26 | Advanced Micro Devices, Inc., Sunnyvale | Method for producing a multi-gate transistor with homogeneously silicided land end regions |
US20110001169A1 (en) * | 2009-07-01 | 2011-01-06 | International Business Machines Corporation | Forming uniform silicide on 3d structures |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4996574A (en) * | 1988-07-01 | 1991-02-26 | Fujitsu Limited | MIS transistor structure for increasing conductance between source and drain regions |
US5300455A (en) * | 1990-12-13 | 1994-04-05 | France Telecom | Process for producing an electrically conductive diffusion barrier at the metal/silicon interface of a MOS transistor |
US5623155A (en) * | 1994-11-24 | 1997-04-22 | Seimens Aktiengesellschaft | MOSFET on SOI substrate |
US5915183A (en) * | 1998-06-26 | 1999-06-22 | International Business Machines Corporation | Raised source/drain using recess etch of polysilicon |
US6091076A (en) * | 1996-06-14 | 2000-07-18 | Commissariat A L'energie Atomique | Quantum WELL MOS transistor and methods for making same |
US6207511B1 (en) * | 1997-04-30 | 2001-03-27 | Texas Instruments Incorporated | Self-aligned trenched-channel lateral-current-flow transistor |
US6252284B1 (en) * | 1999-12-09 | 2001-06-26 | International Business Machines Corporation | Planarized silicon fin device |
US6274913B1 (en) * | 1998-10-05 | 2001-08-14 | Intel Corporation | Shielded channel transistor structure with embedded source/drain junctions |
US6495882B2 (en) * | 1999-12-16 | 2002-12-17 | Spinnaker Semiconductor, Inc. | Short-channel schottky-barrier MOSFET device |
US7265424B2 (en) * | 2001-07-30 | 2007-09-04 | Infineon Technologies Ag | Fin Field-effect transistor and method for producing a fin field effect-transistor |
-
2001
- 2001-07-30 DE DE10137217A patent/DE10137217A1/en not_active Ceased
-
2002
- 2002-07-26 EP EP02794490A patent/EP1412986A2/en not_active Withdrawn
- 2002-07-26 WO PCT/DE2002/002760 patent/WO2003015182A2/en not_active Application Discontinuation
- 2002-07-30 TW TW091117014A patent/TW554537B/en not_active IP Right Cessation
-
2004
- 2004-01-30 US US10/768,971 patent/US7265424B2/en not_active Expired - Fee Related
-
2007
- 2007-08-02 US US11/833,080 patent/US20080035997A1/en not_active Abandoned
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4996574A (en) * | 1988-07-01 | 1991-02-26 | Fujitsu Limited | MIS transistor structure for increasing conductance between source and drain regions |
US5300455A (en) * | 1990-12-13 | 1994-04-05 | France Telecom | Process for producing an electrically conductive diffusion barrier at the metal/silicon interface of a MOS transistor |
US5623155A (en) * | 1994-11-24 | 1997-04-22 | Seimens Aktiengesellschaft | MOSFET on SOI substrate |
US6091076A (en) * | 1996-06-14 | 2000-07-18 | Commissariat A L'energie Atomique | Quantum WELL MOS transistor and methods for making same |
US6207511B1 (en) * | 1997-04-30 | 2001-03-27 | Texas Instruments Incorporated | Self-aligned trenched-channel lateral-current-flow transistor |
US5915183A (en) * | 1998-06-26 | 1999-06-22 | International Business Machines Corporation | Raised source/drain using recess etch of polysilicon |
US6274913B1 (en) * | 1998-10-05 | 2001-08-14 | Intel Corporation | Shielded channel transistor structure with embedded source/drain junctions |
US20010036693A1 (en) * | 1998-10-05 | 2001-11-01 | Brigham Lawrence N. | Shielded channel transistor structure with embedded source/drain junctions |
US6252284B1 (en) * | 1999-12-09 | 2001-06-26 | International Business Machines Corporation | Planarized silicon fin device |
US6495882B2 (en) * | 1999-12-16 | 2002-12-17 | Spinnaker Semiconductor, Inc. | Short-channel schottky-barrier MOSFET device |
US7265424B2 (en) * | 2001-07-30 | 2007-09-04 | Infineon Technologies Ag | Fin Field-effect transistor and method for producing a fin field effect-transistor |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070152272A1 (en) * | 2005-12-29 | 2007-07-05 | Jeong Ho Park | Method for fabricating a transistor using a soi wafer |
US7622337B2 (en) * | 2005-12-29 | 2009-11-24 | Dongbu Hitek Co., Ltd. | Method for fabricating a transistor using a SOI wafer |
US20110068404A1 (en) * | 2009-09-18 | 2011-03-24 | Kabushiki Kaisha Toshiba | Semiconductor device and method for manufacturing the same |
US20120208329A1 (en) * | 2009-09-21 | 2012-08-16 | International Business Machines Corporation | Integrated circuit device with series-connected field effect transistors and integrated voltage equalization and method of forming the device |
US8507333B2 (en) * | 2009-09-21 | 2013-08-13 | International Business Machines Corporation | Integrated circuit device with series-connected field effect transistors and integrated voltage equalization and method of forming the device |
WO2014159481A1 (en) * | 2013-03-14 | 2014-10-02 | International Business Machines Corporation | Partially isolated fin-shaped field effect transistors |
US9053965B2 (en) | 2013-03-14 | 2015-06-09 | International Business Machines Corporation | Partially isolated Fin-shaped field effect transistors |
US9634000B2 (en) | 2013-03-14 | 2017-04-25 | International Business Machines Corporation | Partially isolated fin-shaped field effect transistors |
US20150014773A1 (en) * | 2013-07-12 | 2015-01-15 | International Business Machines Corporation | Partial FIN On Oxide For Improved Electrical Isolation Of Raised Active Regions |
US9219114B2 (en) * | 2013-07-12 | 2015-12-22 | Globalfoundries Inc. | Partial FIN on oxide for improved electrical isolation of raised active regions |
US20160079397A1 (en) * | 2013-07-12 | 2016-03-17 | Globalfoundries Inc. | Partial fin on oxide for improved electrical isolation of raised active regions |
Also Published As
Publication number | Publication date |
---|---|
EP1412986A2 (en) | 2004-04-28 |
TW554537B (en) | 2003-09-21 |
WO2003015182A2 (en) | 2003-02-20 |
DE10137217A1 (en) | 2003-02-27 |
US20040217408A1 (en) | 2004-11-04 |
WO2003015182A3 (en) | 2003-08-07 |
US7265424B2 (en) | 2007-09-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20080035997A1 (en) | Fin Field-Effect Transistor and Method for Fabricating a Fin Field-Effect Transistor | |
US6812075B2 (en) | Self-aligned dog-bone structure for FinFET applications and methods to fabricate the same | |
KR100909886B1 (en) | U-gate transistors and methods of fabrication | |
JP5409997B2 (en) | Method for forming a gate in a FinFET device and method for manufacturing a semiconductor device | |
EP1639649B1 (en) | Nonplanar semiconductor device with partially or fully wrapped around gate electrode and methods of fabrication | |
US6967377B2 (en) | Double-gate fet with planarized surfaces and self-aligned silicides | |
US8263467B2 (en) | Process for fabricating a self-aligned deposited source/drain insulated gate field-effect transistor | |
US9245975B2 (en) | Recessed channel insulated-gate field effect transistor with self-aligned gate and increased channel length | |
US7652322B2 (en) | Split gate flash memory device having self-aligned control gate and method of manufacturing the same | |
US20060088967A1 (en) | Finfet transistor process | |
US5789778A (en) | Semiconductor device with gate insulator film | |
US20040126975A1 (en) | Double gate semiconductor device having separate gates | |
US7316945B2 (en) | Method of fabricating a fin field effect transistor in a semiconductor device | |
US20040207019A1 (en) | Fin-based double poly dynamic threshold CMOS FET with spacer gate and method of fabrication | |
US7494895B2 (en) | Method of fabricating a three-dimensional MOSFET employing a hard mask spacer | |
JP2006505949A (en) | Planarization of gate materials to improve the critical dimensions of semiconductor device gates. | |
US20060170053A1 (en) | Accumulation mode multiple gate transistor | |
US7335945B2 (en) | Multi-gate MOS transistor and method of manufacturing the same | |
KR20050108916A (en) | Methods of forming a fin field effect transistor using damascene process | |
US6876042B1 (en) | Additional gate control for a double-gate MOSFET | |
US20070010059A1 (en) | Fin field effect transistors (FinFETs) and methods for making the same | |
US6911697B1 (en) | Semiconductor device having a thin fin and raised source/drain areas | |
CN106328537B (en) | Semiconductor device and method of manufacturing the same | |
US6146952A (en) | Semiconductor device having self-aligned asymmetric source/drain regions and method of fabrication thereof | |
JP2005504435A (en) | Method for wrap gate MOSFET |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |