WO2002075262A1 - Element de detection infrarouge et procede de fabrication de cet element et equipement de mesure de la temperature - Google Patents
Element de detection infrarouge et procede de fabrication de cet element et equipement de mesure de la temperature Download PDFInfo
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- WO2002075262A1 WO2002075262A1 PCT/JP2002/000812 JP0200812W WO02075262A1 WO 2002075262 A1 WO2002075262 A1 WO 2002075262A1 JP 0200812 W JP0200812 W JP 0200812W WO 02075262 A1 WO02075262 A1 WO 02075262A1
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- structural layer
- junction
- detecting element
- infrared
- temperature
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 25
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- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 abstract description 73
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- IOJNPSPGHUEJAQ-UHFFFAOYSA-N n,n-dimethyl-4-(pyridin-2-yldiazenyl)aniline Chemical compound C1=CC(N(C)C)=CC=C1N=NC1=CC=CC=N1 IOJNPSPGHUEJAQ-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/10—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors
- G01J5/12—Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using thermoelectric elements, e.g. thermocouples
- G01J5/14—Electrical features thereof
- G01J5/16—Arrangements with respect to the cold junction; Compensating influence of ambient temperature or other variables
Definitions
- the present invention relates to a thermopile type infrared detecting element and a method for manufacturing the same. Background technology
- thermometer temperature measuring device
- the ear-type thermometer obtains a body temperature based on an output from an infrared detecting element that converts received infrared light into an electric signal.
- various types of devices such as a pyroelectric thermopile type device, are known as infrared detecting devices. However, they can be mass-produced by using a semiconductor manufacturing process, and can be reduced in size.
- Certain thermopile infrared detectors are also used as thermometers in thermometers.
- a thermopile type infrared detecting element is simply referred to as an infrared detecting element unless otherwise specified.
- FIG. 26 schematically shows an infrared sensor 100 equipped with a thermopile type infrared detecting element 110.
- the infrared sensor 100 has an infrared detecting element 110 provided with a thermopile 12 and a thermistor 120, and these infrared detecting element 110 and the thermistor 120 are package base material 13 It is mounted on the 0, and further housed in the Gate 140, and the whole is integrated.
- the thermistor 120 is used to determine the reference temperature of the thermopile 12 formed on the infrared detecting element 110, that is, the temperature of the cold junction.
- the infrared detecting element 110 is formed by etching the silicon substrate 2 so that the central portion 10 on the lower surface or the rear surface is hollowed and the thin film portion 1 16 in which only the thin film remains And a thick portion (thick portion) 117 that the silicon substrate 2 remains without being etched. That is, the infrared detecting element 110 has a structure in which a thin portion (membrane) is formed on the upper side by making the lower part of the center of the base 115 a hollow part. Above the thin film portion 1 16 and above the central portion 10 of the silicon substrate 2, a film is formed by a method such as sputter deposition of gold black, and an infrared absorber 11 for absorbing infrared light is formed. I have.
- the infrared absorber 11 changes its temperature by absorbing infrared rays, and is detected by a plurality of thermocouples 14 provided on all sides of the infrared absorber 11.
- the hot junction 17 of each thermocouple 14 is placed near the infrared absorber 11 of the thin film section 16, and the cold junction 18 of each thermocouple 14 is the silicon substrate 2 of the thick section 1 17 Above the peripheral part 9 of the vehicle.
- These thermocouples 14 are connected in series to form one thermopile 12.
- thermoelectric force corresponding to a temperature change occurring between the hot junction 17 and the cold junction 18 of the thermopile 12 is detected, and the Calculate the temperature difference between hot junction 17 and cold junction 18 based on the output voltage. Then, the temperature of the cold junction 18 is calculated based on the output of the thermistor 120, and the temperature difference is corrected by the temperature of the cold junction 18 to determine the body temperature.
- the thermistor 120 which is used to determine the temperature of the cold junction 18 of the thermopile 12, is located at a side of the infrared detector 110 at a slight distance from the infrared detector 110.
- thermometers for example, 37. (Accuracy of ⁇ 0.1 ° C is required in the temperature range of ⁇ 39 ° C, and extremely high-precision temperature measurement is required. Therefore, such errors must be minimized.
- the infrared sensor 100 requires a space for disposing the thermistor 120, so that the element itself cannot be reduced to a small size. 0 is placed in contact with the infrared sensor 100 to improve the accuracy of the temperature of the cold junction detected by the thermistor 120. Even if it is used, it is difficult to efficiently integrate the infrared detectors in a compact manner.
- the present applicant has made a PN junction, for example, a diode in the silicon substrate 2 and utilizes the fact that the forward voltage drop changes almost linearly depending on the temperature.
- An infrared detection element that detects the temperature of the cold junction by using the infrared sensor has been proposed. According to this infrared detecting element, the temperature of the cold junction can be accurately detected and can be very compactly collected.
- FIG. 27 shows a cross section of a part of the infrared detecting element.
- a diode D is formed in the peripheral portion 9 of the silicon substrate 2, and the temperature of the cold junction 18 of the thermopile 12 is detected by the diode D.
- This diode D is formed by forming a field oxide film (LoCOS) 151 on the surface of the silicon substrate 2 and ion-implanting it into the region where the device is isolated. Consists of the domain DN. That is, after forming a field oxide film 151 on the silicon substrate 2, the diode D is patterned on the surface of the silicon substrate 2 by patterning the oxide film 151 on the peripheral portion 9 of the silicon substrate 2.
- LiCOS field oxide film
- Each of the regions DP and DN can be formed by a semiconductor process in which the regions DP and DN are formed in the silicon substrate 2.
- the thermopile type infrared detecting element forms a conductor D 16 made of polysilicon and a conductor 15 made of aluminum, which constitute the thermocouple 14, after forming a diode D composed of the regions DP and DN.
- the film 15 2, the surface protective film 15 3, the infrared absorber 11, and the like are also formed using a semiconductor manufacturing process. For this reason, the thermopile type infrared detecting element provided with the diode can be easily formed in a series of steps by the semiconductor manufacturing technology, and the manufacturing cost can be reduced.
- the diode D can be arranged near the cold junction 18 of the thermopile 12, so that the temperature of the cold junction 18 can be accurately detected. Also, since the space for disposing the thermistor 120 can be reduced, an infrared detecting element that is compact and compact, including the function of measuring the reference temperature, can be realized. On the other hand, there is always a need to improve the measurement accuracy of thermopiles 12.
- the field oxide film 151 has a very low etching rate with respect to an etchant for etching a silicon substrate, for example, xenon fluoride, potassium hydroxide, and the like.
- the radius of the field oxide film 15 1 changes the shape of the aluminum conductor 15 and the polysilicon conductor 16 of the thermocouple 14 formed above the film.
- the resistance of these conductors increases from the original resistance, causing unnecessary voltage drop. Therefore, it affects the measurement accuracy of the temperature difference between the hot junction 17 and the cold junction 18 measured by the thermopile 12.
- the infrared detection element 150 described above is extremely accurate because it can accurately detect the temperature of the cold junction with the diode D, but if a more accurate temperature measurement is to be performed, the field oxide film There is a possibility that the measurement error of the thermopile 12 due to the deformation of 15 1 cannot be ignored.
- the degree of bending of the field oxide film 151 varies depending on various factors such as manufacturing process variations, atmospheric pressure, environmental temperature, etc., so that the temperature detected by the thermopile 12 may be varied by an appropriate factor. It is difficult to remove the influence of the deformation of the field oxide film 151 by correcting.
- an infrared detecting element capable of accurately detecting the temperature of a cold junction by a PN junction.
- a first structural layer made of silicon nitride is formed above the semiconductor substrate, and the element isolation for forming the PN junction for detecting the temperature of the cold junction is performed.
- the first structural layer is used as a means for etching and as a stopper for etching when forming a thin film portion. That is, in the method for manufacturing an infrared detecting element of the present invention, a step of forming a first structural layer made of silicon nitride above a semiconductor substrate, and a step of patterning the first structural layer at a peripheral portion of the semiconductor substrate.
- the infrared detection element of the present invention comprises a semiconductor substrate having a hollow portion removed by etching from below, and a silicon nitride silicon film formed above the semiconductor substrate and having a central portion as a thin film structure.
- a first structural layer made of silicon nitride is formed above the semiconductor substrate instead of the field oxide film. If the first structural layer serves as a stopper when the center of the semiconductor substrate is etched from below, the silicon nitride has a lower etching rate than the oxide film (silicon oxide). And the thin film structure left by etching The structure can be made even thinner than when formed of silicon oxide. For this reason, with the infrared detecting element manufactured by the manufacturing method of the present invention and the infrared detecting element having the configuration of the present invention, it is possible to make the thin film portion thinner and to reduce the escape of heat. . Therefore, the measurement error of the thermopile can be further reduced, and a highly accurate temperature can be obtained. Further, by making the thin film portion thinner, the heat capacity of the thin film portion is reduced, and the temperature of the hot junction rises more quickly, so that the response speed can be increased.
- the manufacturing method of the present invention and the structure of the present invention are adopted, and the first structural layer made of silicon nitride is formed on the silicon substrate, thereby isolating the surface of the semiconductor substrate from the element and maintaining the reference temperature. It is possible to realize at the same time to create a PN junction for measuring the temperature with high accuracy and to make the temperature measurement with a thermopile even more accurate.
- the infrared detecting element whose measurement accuracy has been improved by forming the PN junction.
- this infrared detecting element it is possible to provide a temperature measuring device that can measure the temperature more accurately without being affected by the temperature of the measurement environment.
- the step of forming the first structural layer made of silicon nitride and the step of patterning the first structural layer to form a PN junction are also included in the semiconductor manufacturing process.
- the infrared detection element of the present invention can be mass-produced at low cost. Therefore, by using the infrared detecting element of the present invention, a highly accurate temperature measurement can be performed, and a compact and low-cost temperature measuring device can be provided.
- the infrared absorber is provided above the central portion so as to cover at least the hot junction of the thermopile or the vicinity thereof. It is desirable to have a process for forming No.
- the temperature rises as the infrared absorber absorbs infrared light so the temperature difference between the hot junction and the cold junction can be increased, and the output voltage of the thermopile can be increased. Can be. Thereby, the sensitivity of the temperature measurement can be increased.
- the first structural layer made of silicon nitride by a low pressure (low pressure) CVD method (Low Pressure Chemical Vapor Deposition).
- the first structural layer made of silicon nitride formed by this method becomes a film having internal stress in the tensile direction. For this reason, the first structural layer tends to shrink, so that distortion ⁇ bending hardly occurs. Therefore, the deformation of the thin film structure can be further prevented, and the measurement error factor of the thermopile can be further reduced. Therefore, it is possible to provide an infrared detecting element and a temperature measuring device capable of measuring temperature with higher accuracy.
- a PN junction for obtaining a reference temperature it is desirable to form a plurality of PN junctions.
- a plurality of PN junctions By forming a plurality of PN junctions and calculating the difference between the forward voltage drops of the PN junctions, the effect of the reverse saturation current on the voltage drop can be canceled. Therefore, it is possible to further improve the measurement accuracy of the reference temperature, and to provide an infrared ray detecting element and a temperature measuring device capable of obtaining a more accurate temperature.
- a diode is such a PN junction.
- the PN junction is at the periphery of the semiconductor substrate, a reference temperature close to the cold junction can be obtained with high accuracy. Furthermore, in the case of a PN junction extending along the periphery of the semiconductor substrate, if a plurality of cold junctions constituting a thermopile are arranged on all sides of the infrared absorber formed above the center of the semiconductor substrate, It is more preferable that the average temperature of each cold junction can be obtained at the PN junction, and a more accurate temperature of the cold junction can be obtained. '' Also, when forming a PN junction extending long along the peripheral portion, the first and second conductive layers of the PN junction are respectively provided on the upper surfaces of the first and second conductor layers.
- Electrodes can reduce the potential difference between the conductor layers having the same polarity, and can more accurately obtain the reference temperature. If the first structural layer made of silicon nitride is formed directly on the surface of a semiconductor substrate made of silicon, sufficient adhesion may not be ensured between them. For this reason, before forming the first structural layer on the semiconductor substrate, a first bonding layer made of silicon oxide is formed on the semiconductor substrate to improve the adhesion between the semiconductor substrate and the first structural layer. It is desirable to increase. Further, since the first bonding layer is intended for bonding, it does not require a function as a stopper, and can be thinner than the first structural layer.
- the first structural layer made of silicon nitride formed by low-pressure CVD generally has strong internal stress in the tensile direction, so that the cause of bending can be eliminated.
- the first structural layer made of silicon nitride formed by low-pressure CVD generally has a strong internal stress in the tensile direction. Therefore, if a film having a thickness sufficient to eliminate the bending of the thin film portion is formed, the first structure layer is formed. May be peeled off. Therefore, in the manufacturing method of the present invention, a step of forming a second structural layer made of silicon oxide on the first structural layer, and a third step made of silicon nitride on the second structural layer It is also possible to provide a step of forming a structural layer.
- An infrared ray detecting element having a second structural layer made of silicon oxide and a third structural layer made of silicon nitride on the first structural layer has an additional component to eliminate bending of the thin film portion. It is possible to form a film having a thickness separately for the first structural layer and the third structural layer. Therefore, even if the film thickness is set so that the first and third structural layers do not peel off, the stress in the tensile direction can be easily set for the entire thin film portion.
- the central part of the semiconductor substrate is removed by etching in order to form a thin film structure, but before the process, the surface is protected above the semiconductor substrate. It is desirable to form a film so that the metal layer constituting the thermopile is not affected by the etchant.
- the semiconductor substrate may be a P-conductivity type silicon substrate, but is preferably an N-conductivity type.
- an N inversion layer is formed below the insulating layer provided on the surface of the silicon substrate, and a reverse current flows through the N inversion layer to reduce the forward characteristics of the diode. to degrade.
- an N-inversion layer is not formed, and a good forward characteristic of a diode is obtained, so that accurate temperature measurement is possible.
- the temperature measuring device using the infrared detecting element of the present invention is also suitable for a thermometer that requires highly accurate measurement of body temperature.
- a thermometer that requires highly accurate measurement of body temperature.
- an ear thermometer by providing a cylindrical part whose tip can be inserted into the ear canal, and arranging the infrared detection element with the upper part of the central part facing the tip of the cylindrical part, the body temperature can be increased.
- a thermometer with high sensitivity for temperature measurement can be provided by employing an infrared detection element in which an infrared absorber is laminated above the center.
- FIG. 1 is a diagram showing a schematic configuration of an infrared detecting element as one embodiment of the present invention.
- FIG. 2 is a diagram showing a configuration on the front side of an infrared detecting element as one embodiment of the present invention.
- FIG. 3 is a diagram for explaining a thermopile of an infrared detecting element as one embodiment of the present invention.
- FIG. 4 is a cross-sectional view for explaining a detailed configuration of the infrared detecting element as one embodiment of the present invention.
- FIG. 5 is a view illustrating a manufacturing process of the infrared detecting element as one embodiment of the present invention, and is a view illustrating a step of forming a first structural layer on a silicon substrate.
- FIG. 6 is a view showing a step of manufacturing a diode, following FIG.
- FIG. 7 is a view showing a step of forming an oxide film and a conductor made of polysilicon on the first structural layer, following FIG.
- FIG. 8 is a view showing a step of patterning a conductor made of polysilicon, following FIG.
- FIG. 9 is a view showing a step following FIG. 8 for forming a two-layer oxide film on a conductor made of polysilicon.
- FIG. 10 is a view showing a step following FIG. 9 for patterning two oxide films formed on a conductor made of polysilicon.
- FIG. 11 is a view showing a step of forming a thermopile, following FIG. 10.
- FIG. 12 is a view showing a step of forming a two-layer surface protective film and an infrared absorber, following FIG. 11.
- FIG. 13 is a sectional view showing a different example of the infrared detecting element.
- FIG. 14 is a diagram showing the appearance of an ear thermometer using an infrared detecting element as one embodiment of the present invention.
- FIG. 15 is a block diagram showing a schematic configuration of the ear thermometer shown in FIG.
- FIG. 16 is a partial cross-sectional view of an infrared detecting element according to another embodiment of the present invention.
- FIG. 17 is a diagram showing a configuration of a front surface side of an infrared detection element according to another embodiment of the present invention.
- FIG. 18 is a view illustrating a manufacturing process of an infrared detecting element according to another embodiment of the present invention, and is a view illustrating a step of forming a first structural layer on a silicon substrate.
- FIG. 19 is a view showing a step of manufacturing a diode, following FIG. FIG. 20 is a view following FIG. 19, showing a step of forming an oxide film and a conductor made of polysilicon on the first structural layer.
- FIG. 21 is a view showing a step of patterning a conductor made of polysilicon, following FIG. 20.
- FIG. 22 is a view showing a step of forming two oxide films on a conductor made of polysilicon, following FIG. 21.
- FIG. 23 is a view showing a step following FIG. 22 of patterning two oxide films formed on a conductor made of polysilicon.
- FIG. 24 is a view showing a step of forming a thermopile, following FIG. 23.
- FIG. 25 is a view showing a step of forming a two-layer surface protective film and an infrared absorber, following FIG. 24.
- FIG. 26 is a diagram showing a conventional infrared detecting element.
- FIG. 27 is a cross-sectional view for explaining the configuration of an infrared detecting element conventionally proposed by the present applicant.
- Figure 1 shows the schematic configuration of the infrared detector.
- the infrared detecting element 1 of this example has a silicon substrate 2 in which a central portion 10 is removed by etching from below, and a thin film portion 4 and a silicon substrate 2 in which only a thin film remains in the central portion 10. Has a thick portion 3 which remains without being etched.
- an infrared absorber 11 in which gold black is formed into a substantially square film by a method such as sputter deposition is formed.
- the infrared detection element 1 includes a plurality of thermocouples 14 arranged on four sides of the infrared absorber 11.
- the hot junction 17 of each thermocouple 14 is arranged below the infrared absorber 11 of the thin film part 4, and the cold junction 18 of each thermocouple 14 is arranged in the thick part 3.
- These thermocouples 14 are connected in series to form one thermopile 12.
- the diodes D 1 and D 2 for detecting the temperature of the cold junction 18 of the thermopile 12 are formed in the peripheral portion 9 of the silicon substrate 2, that is, in the thick portion 3. I have.
- FIG. 2 is a diagram showing a configuration of the infrared detection element 1 on the front side.
- the structures formed on the upper surface 2a of the silicon substrate 2 are shown in plan, but these structures are actually formed in several different layers.
- the infrared absorber 11 formed into a substantially square film is formed at the center of the thin film part (membrane) 4 located at the center of the upper surface 2a of the silicon substrate 2.
- a plurality of thermocouples 14 are arranged on the four sides.
- a thermopile 12 is formed by connecting the plurality of thermocouples 14 in series, and an output voltage of the thermopile 12 is obtained from terminals T 1 and T 2.
- thermocouple 14 is a diagram for explaining the thermopile 12, and shows the configuration of the thermocouple 14 in an enlarged manner.
- thermocouple 14 two types of conductors are used, a conductor 15 made of aluminum (A1) and a conductor 16 made of polysilicon (Po1y-Si).
- the conductor 16 made of polysilicon is linearly formed so as to extend in four directions from a position slightly overlapping the infrared absorber 11. Further, one end 16a of one of the infrared absorbers 11 of the adjacent polysilicon conductor 16 and the other thick end 3 of the polysilicon conductor 16 are connected. 6b are electrically connected by a conductor 15 made of aluminum.
- thermocouple 14 having a hot junction 17 on the side of the infrared absorber 11 and a cold junction 18 on the side of the thick portion 3 serving as a heat sink is formed, and they are connected in series.
- One thermopile 12 is constructed.
- diodes D 1 and D 2 are formed in the peripheral portion 9 which becomes the thick portion 3 of the silicon substrate 2. These diodes D 1 and D 2 extend in a band along the peripheral portion 9 of the silicon substrate 2, and are formed so as to surround four sides of the central membrane 4. It also surrounds the cold junction 18 of each thermocouple 14 so that the average temperature of the thick part 3 where the multiple cold junctions 18 are located is reflected in the outputs of the diodes D 1 and D 2.
- Diode D 1 is formed of a first conductive layer DP formed so as to surround cold junction 18 and a second conductive layer formed on the outer peripheral side of first conductive layer DP and parallel to this region DP. It is composed of the electrical layer DN1.
- the diode D2 includes a first conductive layer DP and a second conductive layer DN2 formed in parallel with the region DP on the inner peripheral side.
- the first conductor layer DP is a P + diffusion layer doped with an acceptor impurity by ion-implanting boron (B) into the silicon substrate 2 and functions as an anode of a diode.
- the second conductive layers DN 1 and DN 2 are n + diffusion layers doped with a single impurity by ion implantation of phosphorus (P) into the silicon substrate 2.
- the output of the two diodes D 1 and D 2 that share this node are the anode terminal DA and the power source terminal DK 1 formed in the thick part 9. And connected to DK 2. Therefore, by supplying a predetermined current to these diodes D 1 and D 2, it becomes possible to measure the forward voltage drop in these diodes D 1 and D 2, and to accurately determine the reference from the difference. The temperature can be determined.
- the reference temperature that is, the temperature of the cold junction
- the reference temperature can be obtained with higher accuracy by using the difference between the forward voltage drops. be able to. That is, the relationship between the forward current IF of the diode and the forward voltage (or forward voltage drop) VF is as follows.
- I F I S (e X p (q V F / KT) — 1)
- Equation 1 can be transformed to equation 2 by solving for VF.
- V F (T / q) 1 o g (I F / I S)
- the temperature of the cold junction 18 can be obtained based on the forward voltage drop VF of the diode D1 or D2.
- the forward current IF and the reverse saturation current IS Since it is relatively difficult to directly calculate these current values, it is often necessary to measure the relationship between temperature and voltage in advance, store it in a table, and calculate the temperature based on the detected forward voltage VF. Considered a realistic method.
- the difference F of the forward voltage drop VF is obtained, the following equation 3 is obtained. '
- Equation 3 becomes Equation 4 below.
- ⁇ VF (KT / q) l o g (IF 1 / IF 2)
- AVF / T (K / q) l o g (I F 1 / I F 2)... (5)
- the temperature of the thick portion 3 where the diodes D 1 and D 2 are installed that is, the cold junction 18 Can be accurately determined.
- FIG. 4 is a cross-sectional view showing a structure stacked above the semiconductor substrate 2 2a.
- the infrared detecting element 1 includes, in order from the bottom, a first bonding layer 21 made of silicon oxide, a first structural layer 22 made of silicon nitride, and a bonding layer on a silicon substrate 2.
- Oxide film 31, polysilicon conductor 16 constituting thermocouple 14, two layers of silicon oxide films 32 and 33, and two layers of surface protective films 38 and 3 9 are laminated, and an infrared absorber 11 is formed thereon. Then, the central portion of the semiconductor substrate 2 is etched from below 2b, and the central portion 10 becomes the thin film portion 4.
- the first structural layer 22 made of silicon nitride is a film formed by a low-pressure (low-pressure) CVD method.
- silicon nitride has a smaller etching rate than silicon oxide, such as xenon fluoride, which etches silicon, and an etchant such as a hydrating hydroxide. Therefore, it is superior to silicon oxide as an etching stopper, and can reliably prevent erosion even when it is thin. Therefore, the etching for forming the central portion 10 can be reliably controlled by the first structure layer 22.
- silicon nitride has insulating properties like silicon oxide, and can be isolated from each other by forming it on the surface of a silicon substrate.
- the first structural layer 22 extending to the peripheral portion 9 of the silicon substrate 2 is patterned to form the respective regions DN1, DN2 and DP constituting the diodes D1 and D2. Is a film for element isolation. Therefore, in the infrared detecting element 1 of the present embodiment, as described above, by forming the first structural layer 22 made of silicon nitride over the upper surface 2a of the silicon substrate 2, it is possible to form a diode as described above. Element isolation can be formed and sufficiently thin without bending It is possible to form a thin film.
- the thin film section is thinned to prevent heat from escaping without increasing the complexity of the manufacturing process.
- the first bonding layer 21 made of silicon oxide below the first structural layer 22 is used to secure adhesion between the first structural layer 22 made of silicon nitride and the silicon substrate 2.
- Layer. a conductor 16 made of polysilicon is formed above the central portion 10 of the first structural layer 22 via an oxide film 31 that functions as an etching stopper.
- a conductor 15 made of aluminum is formed thereon, and a thermocouple 14 is formed.
- the regions of the silicon substrate 2 separated by the first structural layer 22 become conductive regions DN1, DN2 and DP constituting the diodes D1 and D2.
- Aluminum-aluminum wiring 36 is formed on the top.
- An oxide film 32 as an insulating layer and an oxide film 33 for planarization are laminated so as to cover the central portion 10 and the peripheral portion 9, and a silicon oxide film A surface protection film 38 and a surface protection film 39 made of silicon nitride are provided.
- An infrared absorber 11 is formed at the center 10 of the uppermost layer, and the upper part of the hot junction 17 of the thermopile 12 is covered with the infrared absorber 11. The temperature of the infrared absorber 11 rises by absorbing infrared rays, and a large temperature difference between the hot junction 17 and the cold junction 18 can be secured. Thereby, the output voltage of the thermopile 12 is increased, and the sensitivity of the temperature measurement is increased.
- a first bonding layer 21 made of silicon oxide (Si0 2 ) having a thin film thickness of about 400 A is thermally oxidized on the upper surface 2 a of the P-type silicon substrate 2. It is formed by The first bonding layer 21 is a film for improving the adhesion of the first structural layer 22 formed thereon, and is formed as a film for element isolation in a general semiconductor manufacturing process. This is a very thin film as compared with the field oxide film to be formed. Since the first bonding layer 21 is silicon oxide, it has an internal stress in the compression direction as described above, and tends to bend when the film is made thinner. Since the first structural layer 22 made of silicon nitride having the above internal stress is laminated thereon, the internal stress in the compression direction of the first bonding layer 21 hardly affects the deflection.
- a first structural layer 22 made of silicon nitride (Si 3 N 4 ) having a thickness of about 250 A is formed on the upper surface of the first bonding layer 21 by a low-pressure CVD method. I do.
- the first structural layer 22 is a film having an internal stress in the tensile direction, and can prevent bending when the film is made thin. Furthermore, in the case of the infrared detecting element having the configuration shown in FIG. 27, in order to provide the field oxide film with a sufficient function as a stopper, a film thickness of about 500 to 700 A is required.
- the first structural layer made of silicon nitride having a small etching rate the thickness can be reduced to about 1/3.
- the first structural layer 22 made of silicon nitride serves as a stopper, the first bonding layer 21 thereunder does not need to be expected to function as a stopper, and the thickness is reduced. be able to.
- a photoresist is applied onto the first structural layer 22, exposed and developed, and the photoresist (not shown) is used as a mask to form the first structural layer 22 and the first bonding layer.
- 2 1 is patterned by etching.
- diodes D 1 and D 2 are formed in the regions where the diodes D 1 and D 2 are to be formed in the peripheral portion 9 of the silicon substrate 2 using the first structural layer 22 as an element isolation band.
- polon (B) ions are accelerated and implanted at a high voltage of 35 KeV into the region 25 where the first conductor layer DP is to be formed, and the impurity concentration of 4 ⁇ 10 15 ions Zcm 2 P + diffusion layer (first conductive layer) DP is formed.
- phosphorus (P) ions are implanted into a region 26 where the second conductor layers DN 1 and DN 2 are to be formed at a high voltage of 80 KeV while being accelerated, and 4 ⁇ 10 15 ions are implanted.
- An N + diffusion layer (second conductive layer) having an impurity concentration of / cm 2 is formed with DN 1 and DN 2.
- 900 ⁇ m is applied to recover crystal defects generated at the time of each ion implantation and to activate impurities implanted into the respective regions 25 and 26. Anneal at 20 ° C for 20 min.
- the first structural layer 22 As a result, diodes D 1 and D 2 separated from each other are formed.
- an oxide film (HTO: High Temperature Oxide) 31 having a thickness of about 1000 A is formed by a high temperature CVD method.
- the oxide film 31 thus formed is a hard film having a small impurity diffusion coefficient.
- a metal layer to be overlaid on the oxide film 31, that is, a conductor 16 made of polysilicon or a conductor 15 made of aluminum constituting the thermocouple 14 is formed. Therefore, diffusion of impurities to the silicon substrate 2 side can be prevented.
- a conductor 16 made of polysilicon which is one conductor of the thermocouple 14, is formed on the oxide film 31.
- a conductor 16 made of polysilicon having a thickness of about 4000 A is formed by a CVD method using silane (SiH 4 ) gas.
- the reaction formula is S i H 4 ⁇ S i + H 2 .
- phosphorus is doped as a donor impurity in the polysilicon conductor 16 and thermally diffused to make the sheet resistance 15 ohm / sq.
- a photoresist (not shown) is coated on the polysilicon conductor 16 and exposed and developed, and then, as shown in FIG. 8, the polysilicon conductor 16 is formed using the photoresist as a mask. Is etched and patterned to expose the diffusion layers DP, DN1, and DN2.
- an oxide film (HTO) 32 having a thickness of about 100 OA is formed again by the CVD method, and is further formed on the oxide film 32 by the CVD method.
- An oxide film (BPSG) 33 having a thickness of 000 A is formed.
- This oxide film 33 is made of LTO (Low Temperature Oxide), and the oxide film itself has viscosity to make it easy to flatten.
- the oxide film 33 is planarized. At this time, boron and phosphorus in the film are liable to diffuse, but there is an oxide film 32 made of HTO below the antinode 33, so that the film 32 causes the diffusion of the boron-phosphorus to the silicon substrate side. Blocked.
- Patterning 35 is performed to establish conduction between the formed diffusion layers DP, DN1, DN2 and the conductor 16 made of polysilicon and metal (aluminum metal). That is, a photoresist (not shown) is applied on the oxide film 33, exposed and developed, and the oxide films 33 and 32 are etched using the photoresist as a mask to form the diffusion layers DP, DN1, and DN2. Then, the portions of the conductor 16 corresponding to the hot junction 17 and the cold junction 18 are exposed.
- the metal wiring 36 and the aluminum wiring are formed.
- the conductor 15 of FIG. As a result, the conductor 15 made of aluminum is connected to the conductor 16 made of polysilicon, so that the hot junction 17 and the cold junction 18 are formed.
- a plurality of thermocouples 14 are connected in series to form a thermopile 12.
- an oxide film (BPSG) 33 is formed on the oxide film 32 and planarized, so that when etching, the conductor 15 made of aluminum and the metal wiring 36 are formed. Disconnection can be prevented.
- a surface protection film (PADA) 38 having a thickness of about 2000 A is formed by a plasma CVD method using TEOS (tetraethyl orthosilicate) gas. After the formation of the film 38, SOG (Spin On Glass) is applied and a beta at 400 ° C. and 30 min is performed. Thereby, the surface protection film 38 is planarized.
- TEOS tetraethyl orthosilicate
- a plasma nitride film (S i X Ny) which becomes a second surface protection film (PAD B) 39 having a thickness of about 100 OA is formed on the first surface protection film 38.
- the combination of the thicknesses of the two surface protective films 38 and 39 is not limited to the above, and the surface protective film 38 is set to 2,000, 20,000 or 6000 A, and the thickness of the surface protective film 39 is set to 1 corresponding to each thickness. It can be 0000, 5 000 or ⁇ ⁇ ⁇ ⁇ ⁇ . Further, it is also possible to form the surface protection film 38 of 3000 A and omit the surface protection film 39.
- the thicknesses of the other layers described above are merely examples, and are not limited to the above thicknesses. .
- These surface protection films were formed on the upper surface 2a of the silicon substrate 2, such as the aluminum conductor 15 and the polysilicon conductor 16, when the silicon substrate 2 was etched last. This is a film that prevents the structural layer from being etched. Therefore, if the surface protection film 39 is too thin, the surface protection film 39 is not properly formed in the unevenness and the etchant enters, and the surface protection film 38 is etched to damage the thermopile 12. could be done. Therefore, it is desirable that the film thickness of these two films 38 and 39 be appropriately set according to the etching rate.
- an infrared absorber 11 having a thickness of about 1 to 10 ⁇ Hi is formed by depositing gold black on the surface protective film 39.
- the lower portion 2b of the silicon substrate 2 is masked except for the central portion 10 thereof, and the central portion 10 of the silicon substrate 2 is etched using KOH or NaOH as an etching solution. Anisotropic etching is performed from below. As a result, the central portion 10 of the silicon substrate 2 is removed, and the infrared detecting element 1 shown in FIG. 4 is formed.
- the first structural layer 22 functions as a stopper, so that excessive etching can be prevented. Therefore, the central portion 10 of the silicon substrate 2 can be almost completely removed, and the thin film portion 4 having a desired thickness can be formed in the central portion 10.
- the infrared detecting element 1 of the present example can be manufactured. Then, in the infrared detecting element 1 of the present example, a first structural layer 22 made of silicon nitride is formed on the silicon substrate 2 instead of the field oxide film.
- the structural layer 22 is a film having a strong internal stress in the tensile direction. Therefore, the thin film portion is less likely to be bent, and the measurement error of the thermopile 12 due to the deformation of the thin film portion 4 can be reduced.
- the first structural layer 22 made of silicon nitride is used as a stopper during etching. To function as. For this reason, the first structural layer 22 serving as the stopper can be made thinner than in the configuration using the field oxide film as the stopper, and the heat capacity of the thin film portion 4 can be reduced. Therefore, since the temperature of the thermal junction 17 rises more quickly, it is possible to increase the response speed. Further, by making the second structural layer 22 thinner, the escape of heat from the hot junction 17 to the cold junction 18 can be reduced. Therefore, the measurement error of the thermopile 12 can be further reduced, and a highly accurate temperature can be obtained.
- FIG. 13 shows a modification of the present invention.
- the second structural layer 41 and the third structural layer 42 are formed between the first structural layer 22 and the oxide film 31. That is, a second structural layer 41 made of silicon oxide having a thickness of 550 OA is formed on the first structural layer 22 having a thickness of 1000 A. Then, a third structure layer 42 made of silicon nitride having a thickness of 200 OA is formed on the second structure layer 41 by the same manufacturing method as that of the first structure layer 22. I have. Then, an oxide film 31 is formed thereon, and the structure and manufacturing method above the oxide film 31 are the same as those of the infrared detection element 1 described above.
- This infrared detecting element 1a can form a film having a thickness sufficient to eliminate the radius of the thin film portion 4 into a first structural layer 22 and a third structural layer 42. . Therefore, even if the film thickness is set so that the first structural layer 22 and the third structural layer 42 do not peel off, the stress in the tensile direction of the entire thin film portion 4 becomes easy. That is, it is possible to reduce the measurement error of the thermopile 12 due to the fact that the thin film portion 4 is not bent and the thin film portion 4 is deformed.
- the thin film portion 4 can be further thinned and deformation can be suppressed. Alternatively, the deformation of the thin film portion 4 can be almost completely prevented.
- the structural layers 22 made of silicon nitride are used also as element separating bands, and the diodes D 1 and D 2 for detecting the temperature of the cold junction 18 are used on the semiconductor substrate. It is built in 2.
- diodes D 1 and D 2 The temperature of the substrate 2 can be obtained directly in a state of being in contact with the semiconductor substrate 2, and the reference temperature can be obtained with high accuracy compared to a conventional infrared detecting element in which a thermistor chip is packaged. Further, as described above, by providing two diodes D 1 and D 2 and obtaining the difference between the forward voltage drops, it is possible to easily and accurately measure the temperature.
- the infrared detecting elements 1 and 1a of the present example can minimize the measurement error of the thermopile 12 due to the deformation of the thin film portion 4, and furthermore, the cold junction at the reference temperature can be used. Temperature can also be measured very accurately. Therefore, the measurement error is very small, and the temperature can be measured with high accuracy.
- temperature measurement using a diode has no temperature dependence in theory, there is no need to perform correction like a thermistor, and there is an advantage that an infrared detection element with a wide measurement range can be provided.
- a diode can be formed by the first structural layer 22 made of silicon nitride, and errors due to deformation of the thin film portion can be prevented. Therefore, the manufacturing process is simple as described above, It can be mass-produced by a semiconductor manufacturing process. Therefore, it is possible to provide an infrared detection element with low cost and extremely good measurement accuracy. '
- the diodes D1 and D2 are arranged so as to surround the cold junctions 18 of the thermocouples 14, so that the average temperature of the cold junctions is reduced. Has been detected. Therefore, the temperature of the cold junction can be detected more accurately. Also, a configuration for more accurate measurement of the reference temperature, for example, electrodes are arranged along the conduction band to adjust the potential of the conduction band forming the diodes D1 and D2 extending along the periphery Has been adopted.
- FIG. 14 is a perspective view showing the appearance of an ear thermometer using the infrared detecting element 1 of the present example.
- the ear thermometer 50 of this example has an elongated housing 51 that is easy to grasp with the palm, and can be inserted into the ear hole on the front surface 52 thereof.
- a cylindrical probe 58, an LCD 55 for displaying the body temperature measured by a thermometer, etc., a switch 56 for turning on the power, and a battery box 57 are provided.
- the housing 51 has a built-in infrared detecting element 1 with the infrared absorber 11 facing the tip 58 a of the probe 58. Therefore, the infrared radiation radiated in the ear canal via the probe 58 is received by the infrared absorber 11 of the infrared detection element 1, and the temperature can be measured by the thermopile 12.
- the output of the infrared detecting element 1 that is, the output of the thermopile 12 is changed to the diode D 1
- the temperature determined by the output of D2 and the temperature of the cold junction 18 can be corrected to display highly accurate body temperature (temperature).
- FIG. 15 is a block diagram showing a schematic circuit configuration of the ear thermometer 50.
- the ear-type thermometer 50 of this example is composed of a temperature deriving unit 61 for calculating the temperature using the output from the infrared detecting element 1, a switch 54 for starting the measurement, an LCD 55, and a power supply. And a battery 57.
- the temperature deriving unit 61 supplies the first data output that supplies the difference between the forward voltage drops of the diodes D 1 and D 2 to the CPU 63 as a signal indicating the temperature Tr of the cold junction 18 of the thermopile 12.
- a second data output unit 72 that outputs the output voltage of the thermopile 12 to the CPU 63 as a signal indicating the temperature difference ⁇ between the cold junction 18 and the hot junction 17.
- the CPU 63 that derives the body temperature from the temperature Tr and the temperature difference obtained from the data output sections 71 and 72 and controls the entire thermometer, and the various work areas of the CPU 63 RAM64. Then, the temperature T r of the cold junction 18 obtained from the outputs of the diodes D 1 and D 2 is added to the temperature difference ⁇ between the hot junction 17 and the cold junction 18 obtained from the output of the thermopile 12 2. By doing so, body temperature is derived. The derived body temperature is displayed on the LCD 55 provided on the front surface 52 of the housing 51.
- thermometer 50 since the infrared detecting element 1 described above is incorporated, the output of the thermopile 12 of this element 1 and the diode D1, Based on the output of D2, highly accurate body temperature can always be measured regardless of the use environment. Also, since the infrared detecting element 1 can be supplied at a small cost at low cost using a semiconductor manufacturing process, an ear thermometer 50 using this element 1 is compact, low-cost, and easy to use. The thermometer is purchased and used.
- the infrared detectors 1 and 1a in this example are not limited to ear thermometers, but can be used for other types of thermometers and other types of thermometers. Nevertheless, the temperature can be measured with high accuracy, so the range of applications is wide.
- the present inventors examined the infrared detecting element 1 shown in the above-described embodiment, the output voltages (forward voltages) of the semiconductors Dl and D2 were actually unstable, and an error occurred in the measured temperature. Was found to occur. Therefore, the present inventors have developed an infrared detecting element using an N-type silicon substrate as shown in FIG. 16 in order to obtain an infrared detecting element capable of measuring temperature with higher accuracy.
- FIG. 16 is a partial cross-sectional view of an infrared detecting element according to another embodiment of the present invention.
- the infrared detecting element 1b is an N-substrate in which a silicon substrate 2c diffuses N-conductivity type impurities (donor impurities) such as phosphorus.
- the infrared detecting element 1b is, on the N-type silicon substrate 2c, in order from the bottom, a first bonding layer 21 made of silicon oxide, a first structural layer 22 made of silicon nitride, and a bonding layer.
- the first structural layer 22 made of silicon nitride is a film formed by a low-pressure (reduced-pressure) CVD method similarly to the above-described embodiment, and is a thin film supported by the first structural layer 22. Part 4 is prevented from bending.
- a central portion 10 is etched from below 2b to form a thin film portion 4. Further, in the N-type silicon substrate 2c, the periphery of the thin film portion 4 is a thick portion 3 left as it is without being etched.
- the infrared detecting element 1b is composed of a P + conductor in which P-conductivity-type impurities (acceptor impurities) such as boron are diffused into the peripheral portion 9 of the N-type silicon substrate 2c, that is, the surface portion of the thick portion 3.
- Layers DP la and DP 2 a are formed.
- An N + conductive layer DNa in which an N conductive impurity (donor impurity) such as phosphorus is diffused is provided between the conductive layer DPla and the conductive layer DP2a.
- These conductor layers DPla, DP2a, and DNa constitute two diodes D1a and D2a. That is, the conductor layer DP1a forms an anode of the diode D1a, and DNa forms a force sword of the diode D1a.
- DNa is a diode D2a power source, and DP2a is a diode D2a anode. Diodes D1a and D2a that share these force swords are provided so as to surround the cold junction 18 of the thermocouple 14 similarly to the above embodiment.
- the infrared detecting element 1b formed on the N-type silicon substrate 2c of the present example has conductor layers DP 1a and DP 2a serving as anodes of the diodes D la and D 2a. Are connected to the anode terminals DA 1 and DA 2, and the conductor layer DNa that is to be a power source is connected to the power source terminal DK.
- the infrared detecting element 1c of the present example having the above configuration can be formed substantially in the same manner as the infrared detecting element 1 according to the above embodiment.
- FIG. 25 schematically shows a manufacturing process of the infrared detecting element 1b of the present example.
- the upper surface 2a of the N-type silicon substrate 2c is made of silicon oxide having a thickness of about 400 A (Si 0 2 ) is formed by thermal oxidation.
- the first bonding layer 21 is a film for improving the adhesion of the first structural layer 22 formed thereon, and is formed as a film for element isolation in a general semiconductor manufacturing process. It is much thinner than the field oxide film used. ,
- a first structural layer 22 made of silicon nitride (Si 3 N 4 ) having a thickness of about 250 OA is formed on the upper surface of the first bonding layer 21 by low-pressure CVD.
- the first structural layer 22 is a film having an internal stress in the tensile direction, and can prevent bending when the N-type silicon substrate 2c is thinned.
- a photoresist (not shown) is applied on the first structural layer 22, exposed and developed, and as shown in FIG. 19, the first structural layer 2 is formed using the photoresist as a mask. 2 and the first bonding layer 21 are etched and patterned. Then, the diodes D 1 a and D 2 a are formed in the regions where the diodes D 1 a and D 2 a are to be formed in the peripheral portion 9 of the N-type silicon substrate 2 c using the first structural layer 22 as an element isolation band. .
- a layer (first conductive layer) is formed. Further, in the area 2 6 a forming the second conductor layer DP 1 a and DP 2 a, and injected accelerated boron ions at a high voltage of 3 5 K e V, 4 X 1 0 15 ions Zcm2 P + diffusion layer with impurity concentration (second conductor layer)
- each conductor layer After forming each conductor layer in this way, to recover the crystal defects generated at the time of each ion implantation and to activate the impurities implanted into each region 25a and 26a, 9 Anneal at 0 ° C for 20 min. As a result, the diodes D 1 a and D 2 a separated from each other by the first structural layer 22 are formed.
- an oxide film (HTO: High Temperature Oxide) 31 having a thickness of about 100 A is formed by a high-temperature CVD method. Thereafter, a polysilicon conductor 16 as one conductor of the thermocouple 14 is deposited on the oxide film 31 by a CVD method using silane (SiH 4 ) gas to a thickness of 4 ⁇ m.
- a photoresist is applied onto the conductor 16, exposed and developed, and is etched using the photoresist as a mask, thereby patterning the conductor 16 made of polysilicon as shown in FIG. 21.
- the conductor layers DNa, DP1a and DP2a are exposed.
- an oxide film (HTO) 32 having a thickness of about 1000 A is formed again by the CVD method, and further, the ⁇ 0 method is performed thereon.
- An oxide film (BPSG) 33 having a thickness of 800 A is formed. After the oxide film 33 is formed, annealing under the condition of 900 ° C. and 20 min is performed to flatten the oxide film 33.
- a photoresist (not shown) is applied on the oxide film 33. Exposure and development. And using this as a mask, as shown in Figure 23
- the patterning 35 is performed to expose the diffusion layer, and at the same time, the portions of the conductor 16 corresponding to the hot junction 17 and the cold junction 18 are exposed. .
- thermocouples 14 are connected in series to form a thermopile 12. In this manner, the structure laminated on the upper surface 2a of the semiconductor substrate 2 is almost completed.
- the oxide film 33, the aluminum conductor 15 and the metal wiring 36 are covered by a plasma CVD method using TEOS (tetraethyl orthosilicate) gas.
- a surface protection film (PA DA) 38 having a thickness of about 0.000 A is formed. After forming this film 38, SOG (Spin On Glass) is applied
- a plasma nitride film (S i x) that becomes a second surface protective film (PAD B) 39 having a thickness of about 100 A is formed.
- N y is formed by a plasma enhanced CVD method.
- An infrared absorber 11 having a thickness of about 1 to 10 ⁇ m is formed.
- the lower portion 2b of the N-type silicon substrate 2c is masked except for its central portion 10, and the N-type silicon substrate 2c is etched using K ⁇ H or NaOH as an etchant.
- the central portion 10 is anisotropically etched from below. Thereby, the central portion 10 of the N-type silicon substrate 2c is removed, and the infrared detecting element 1c shown in FIG. 16 is formed.
- the diodes D la and D 2a are excellent. And the output voltage (forward voltage) of the diodes D la and D 2a is much more stable than the diode formed on the P-type silicon substrate.
- a high-accuracy temperature detecting device can be obtained by using the infrared detecting element lb of this example.
- the second structural layer made of silicon oxide shown in FIG. 13 is located between the first structural layer 22 and the oxide film 31. 41 and a third structural layer 42 made of silicon nitride may be provided.
- the first structural layer made of silicon nitride is formed on the semiconductor substrate.
- the first structural layer can be formed as a film having an internal stress in the tensile direction by a low-pressure CVD method, which can prevent the thin film portion from bending, and can be used for forming a thermopile formed on the first structural layer. A more accurate temperature difference can be detected by preventing a shape change.
- the PN junction formed in the semiconductor substrate is separated by the first structural layer, the PN junction for accurately detecting the temperature of the cold junction must also be formed in the semiconductor substrate at the same time. Can be. Therefore, according to the present invention, it is possible to manufacture an infrared detecting element capable of detecting a temperature such as a body temperature more accurately at a low cost, and to provide a compact and accurate temperature measuring apparatus at a low cost using the same. it can.
Description
Claims
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US10/258,641 US6909093B2 (en) | 2001-03-16 | 2002-01-31 | Infrared detecting element, method of manufacturing the same and temperature measuring device |
EP02710445A EP1312903A4 (en) | 2001-03-16 | 2002-01-31 | INFRARED DETECTION ELEMENT AND METHOD FOR THE PRODUCTION THEREOF AND DEVICE FOR MEASURING THE TEMPERATURE |
JP2002573629A JPWO2002075262A1 (ja) | 2001-03-16 | 2002-01-31 | 赤外線検出素子およびその製造方法並びに温度測定装置 |
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US (1) | US6909093B2 (ja) |
EP (1) | EP1312903A4 (ja) |
JP (1) | JPWO2002075262A1 (ja) |
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DE112011101444T5 (de) | 2010-04-26 | 2013-04-11 | HME Co. Ltd. | Temperatursensoreinrichtung und Strahlungsthermometer, der diese Vorrichtung verwendet, Herstellungsverfahren für Temperatursensorvorrichtungen, Mehrlagen-Dünnfilm-Thermosäule, die einen Fotoresistfilm und ein Strahlungsthermometer unter Benutzung dieser Thermosäule verwendet, sowie Herstellungsverfahren einer mehrlagigen Dünnfilm-Thermosäule |
US9759613B2 (en) | 2010-04-26 | 2017-09-12 | Hme Co., Ltd. | Temperature sensor device and radiation thermometer using this device, production method of temperature sensor device, multi-layered thin film thermopile using photo-resist film and radiation thermometer using this thermopile, and production method of multi-layered thin film thermopile |
KR101316615B1 (ko) | 2011-10-20 | 2013-10-15 | 한국표준과학연구원 | 열전소자를 이용한 온도측정기 및 온도 측정 방법 |
WO2018151200A1 (ja) | 2017-02-15 | 2018-08-23 | パナソニックIpマネジメント株式会社 | 赤外線センサチップと、これを用いた赤外線センサ |
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Also Published As
Publication number | Publication date |
---|---|
EP1312903A1 (en) | 2003-05-21 |
EP1312903A4 (en) | 2004-09-29 |
US6909093B2 (en) | 2005-06-21 |
JPWO2002075262A1 (ja) | 2004-07-08 |
CN1457423A (zh) | 2003-11-19 |
US20030111605A1 (en) | 2003-06-19 |
TW593991B (en) | 2004-06-21 |
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