JP5633195B2 - Thermal detection device - Google Patents

Description

  The present invention relates to a heat detection device including a resistance element.

  As a temperature sensor for non-contact measurement of the temperature of a heat source, for example, Japanese Patent Laid-Open No. 2-201229 discloses two thermistor elements having the same resistance temperature characteristic and two fixed resistance elements having the same resistance value. A bridge circuit is used, and one thermistor element is configured to detect the amount of heat of infrared rays radiated from the heat source, and this is used as an infrared detection element, and the other thermistor element is radiated from the heat source. A thermistor bolometer that is shielded from infrared rays and is configured to compensate the temperature of the output signal of the infrared detection element based on the temperature of the ambient atmosphere, is used as a reference temperature sensitive element, and these are housed in the same case. It is disclosed. In such a thermistor bolometer, the infrared detecting element receives the amount of infrared heat from the heat source and the amount of heat from the outside atmosphere, and its electrical resistance changes, while the reference temperature sensing element is from the outside atmosphere. Since the electrical resistance changes in response to the amount of heat, a sensor output corresponding to the temperature of the heat source can be obtained by obtaining the difference between the output signals of both elements. In particular, there is an advantage that a large sensor output can be obtained by designing a circuit so that the resistance values of two thermistor elements and two fixed resistance elements are the same.

Japanese Patent Laid-Open No. 2-201229

  However, in the above-described thermistor bolometer, if the resistance values of the two thermistor elements and the two fixed resistance elements are not selected and combined, the detection error increases, and the variation in sensitivity characteristics as a temperature sensor increases. Become. In particular, when two thermistor elements and two fixed resistance elements are formed on the same substrate, the resistance value of the resistance element is likely to vary due to the influence of the film thickness distribution. Is desired.

  Accordingly, an object of the present invention is to solve the above-described problems and provide a heat detection device that can reduce variations in resistance values of resistance elements.

  In order to solve the above-mentioned problems, a heat detection device according to the present invention detects a heat sensing element for detecting the amount of heat from a heat source, and detects the amount of heat in the ambient atmosphere to compensate the temperature of the temperature sensing element for detection. A reference temperature sensing element, and a first resistance adjusting portion whose resistance can be adjusted according to a cut state, one end of which is connected to the first output terminal and the other end connected to the second common terminal. A first resistance element and a second resistance adjustment unit capable of adjusting a resistance according to a disconnected state, one end of which is connected to the second output terminal and the other end is connected to the second common terminal. A second resistive element. The detection temperature sensing element is connected to the first output terminal and the first common terminal, and the reference temperature sensing element is connected to the second output terminal and the first common terminal. The infrared detecting temperature sensing element, the reference temperature sensing element, the first resistance element, and the second resistance element are formed on the same substrate. At least one of the first output terminal, the second output terminal, the first common terminal, or the second common terminal is either one of the sensing temperature sensing element or the reference temperature sensing element, It is formed between either the first resistance adjustment unit or the second resistance adjustment unit. According to such a configuration, the scattering of the cutting residue generated when the resistance adjusting unit is partially cut out of the first output terminal, the second output terminal, the first common terminal, or the second common terminal. Since it is shielded by at least one of them, the possibility that the cutting residue in a high temperature state adheres to the sensing temperature sensing element or the reference temperature sensing element and damages the element structure is reduced. Sensitivity can be improved.

  The first resistance adjusting unit and the second resistance adjusting unit are preferably frame-shaped connecting resistors. According to such a configuration, since the resistance value of the resistance element can be adjusted stepwise by partial cutting of the frame-shaped connecting resistor, the resistance can be adjusted easily and accurately.

  In addition, as a specific example of a heat detection device, a temperature sensor, a humidity sensor, a gas sensor, etc. can be mentioned, for example. When the heat sensing device functions as a temperature sensor, the sensing temperature sensing element is configured to sense the amount of heat received from the heat source, while the reference temperature sensing element is shielded from the heat source and is used to detect the temperature from the heat source. Configured to be unaffected. The temperature of the heat source can be measured in a non-contact manner by compensating the temperature of the detection signal of the sensing temperature sensing element with the reference temperature sensing element. Also, if the heat sensing device functions as a humidity sensor, the sensing temperature sensing element is configured to sense a change in the amount of heat dissipated from the sensing temperature sensing element to the ambient atmosphere, while the reference temperature sensing element is It is configured so that it is shielded from the external atmosphere and is not affected by humidity changes in the external atmosphere. When the amount of water vapor in the atmosphere surrounding the sensing temperature sensing element changes while the sensing temperature sensing element is heated to the specified operating temperature, the thermal conductivity of the atmosphere changes, so the amount of heat dissipated by the sensing temperature sensing element Changes. The absolute humidity of the outside atmosphere can be measured by compensating the temperature of the detection signal of the sensing temperature sensing element with the reference temperature sensing element. When the heat detection device functions as a gas sensor, the detection temperature sensing element is configured to detect the amount of heat from the reaction film that generates heat or absorbs heat in response to the gas to be detected, while the reference temperature sensing element Is shielded from the reaction film and is not affected by the temperature from the reaction film. The concentration of the gas to be detected can be measured by compensating the temperature of the detection signal of the temperature sensor for detection with the temperature sensor for reference. For example, when a combustible gas is used as the gas to be detected, a catalyst layer for catalytically combusting the combustible gas may be used as the reaction film.

  According to the present invention, it is possible to reduce variations in resistance values of the resistance elements of the heat detection device.

It is a top view of the temperature sensor concerning this embodiment. FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1. It is a circuit block diagram of the temperature sensor concerning this embodiment.

  Embodiments according to the present invention will be described below with reference to the drawings. In the present embodiment, a temperature sensor is illustrated as a specific example of the heat detection device, and the device structure is described in detail. However, the same device structure can be applied to a humidity sensor and a gas sensor. Further, the same members are denoted by the same reference numerals, and redundant description is omitted. Note that the drawings are schematic, and for convenience of explanation, the relationship between the thickness and the planar dimensions, and the ratio of the thickness between devices are within the range where the effects of the present invention can be obtained. May be different.

  FIG. 3 is a circuit configuration diagram of the temperature sensor 100 according to the present embodiment. The temperature sensor 100 includes a half-bridge circuit composed of an infrared detection temperature sensing element 20 and a resistance element 40 connected in series via an output terminal 61, a reference temperature sensing element 30 connected in series via an output terminal 62, and It has a full bridge circuit in which a half bridge circuit composed of the resistance element 50 is connected in parallel. A common terminal 63 is connected between the resistance elements 40 and 50 as a power supply terminal for receiving a power supply from the power supply Vcc and flowing a current through the bridge circuit. A common terminal 64 as a ground terminal is connected between the infrared detecting temperature sensing element 20 and the reference temperature sensing element 30. The infrared detecting temperature sensing element 20 is a sensor element for detecting the amount of heat of infrared rays radiated from a heat source, and the reference temperature sensing element 30 is for temperature compensation of the output signal of the infrared sensing temperature sensing element 20. It is a sensor element for detecting the amount of heat from the external environment. The amount of heat received by the infrared detecting temperature sensing element 20 is not limited to the amount of infrared radiation emitted from the heat source, but also receives the amount of heat from the external environment. By compensating the temperature of the output signal of the temperature sensing element 20 for detection, the amount of infrared heat radiated from the heat source (that is, the temperature of the heat source) can be estimated. For this reason, the infrared detecting temperature sensing element 20 is configured to receive infrared rays emitted from the heat source, while the reference temperature sensing element 30 does not receive infrared rays emitted from the heat source (in other words, , Configured to detect only the amount of heat from the external environment).

  The infrared detecting temperature sensing element 20 and the reference temperature sensing element 30 are not particularly limited as long as they have a sensor element whose electrical characteristics change according to the amount of heat received, and have, for example, resistance temperature characteristics. A bolometer such as a thermistor or a resistance temperature sensor is suitable. In addition, it is preferable to adjust the resistance temperature characteristics of the infrared sensing temperature sensing element 20 and the reference temperature sensing element 30 as much as possible, and to match both resistance value changes due to the influence of heat from the external environment. Similarly, the resistance values of the resistance elements 40 and 50 are preferably as identical as possible. According to such a configuration, in a state where the temperature sensor 100 is not irradiated with infrared rays from the heat source, the voltage between the output terminals 61 and 62 is zero, while the temperature sensor 100 is irradiated with infrared rays from the heat source. Then, an unbalanced voltage (sensor signal) is output between the output terminals 61 and 62 due to the difference in resistance value between the infrared sensing temperature sensing element 20 and the reference temperature sensing element 30. The unbalanced voltage is measured with a voltmeter, and the temperature of the heat source can be estimated by referring to a calibration curve prepared in advance showing the relationship between the unbalanced voltage and the heat source temperature.

1 is a plan view of the temperature sensor 100, and FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. The infrared sensing temperature sensing element 20 includes an individual electrode 65 and a common electrode 67 formed with a predetermined gap interval, and a temperature sensing film 21 formed between these electrodes. The reference temperature sensing element 30 includes an individual electrode 66 and a common electrode 67 formed with a predetermined gap interval, and a temperature sensing film 31 formed between these electrodes. As the material of the temperature sensitive films 21 and 31, for example, a thermistor thin film having a negative temperature coefficient such as amorphous silicon, polysilicon, germanium, silicon carbide, or composite metal oxide is suitable. In order to form a thermistor thin film functioning as the temperature sensitive films 21 and 31, for example, MnNiCo-based oxidation is performed under sputtering conditions of a substrate temperature of 600 ° C., a film forming pressure of 0.5 Pa, an O ₂ / Ar flow rate ratio of 1% and an RF power of 400 W. After depositing about 0.4 μm, the MnNiCo-based oxide film is heat-treated at 650 ° C. for 1 hour in an air atmosphere using a baking furnace, and patterned into a predetermined shape by wet etching using a ferric chloride aqueous solution. That's fine. However, the temperature sensitive films 21 and 31 do not need to be separated for each temperature sensitive element, and may be integrated. In order to form the individual electrodes 65 and 66, the common electrode 67, and the power supply electrode 68, for example, a well-known thin film process such as a sputtering method or a vapor deposition method may be used. A relatively high melting point material having heat resistance that can withstand a film process, a heat treatment process, and the like, and an appropriate conductivity is preferable. For example, molybdenum (Mo), platinum (Pt), gold (Au), tungsten ( W), tantalum (Ta), palladium (Pd), iridium (Ir), or an alloy containing two or more of these metals is preferable. Titanium (Ti) as an adhesion layer may be interposed between these metal bases. The output terminals 61 and 62 are raised electrodes that are stacked on the individual electrodes 65 and 66, respectively, for taking out an electrical signal from the temperature sensitive elements 20 and 30. The common terminal 63 is a raised electrode stacked on the power supply electrode 68 connected to one end of each of the resistance elements 40 and 50, and the common terminal 64 is a raised electrode stacked on the common electrode 67. As the material of these raised electrodes, materials that can be easily electrically connected such as wire bonding and flip chip bonding are preferable, and for example, aluminum (Al), gold (Au), and the like are preferable. The common terminal 63 may be a ground terminal and the common terminal 64 may be a power supply terminal.

  The substrate 10 has a first main surface 10A and a second main surface 10B which is the back surface thereof, and an insulating film 70 is formed on the first main surface 10A. The material of the substrate 10 is not particularly limited as long as it has a suitable mechanical strength and is suitable for fine processing such as etching. For example, a silicon single crystal substrate, a sapphire single crystal A substrate, a ceramic substrate, a quartz substrate, a glass substrate, or the like is preferable. The insulating film 70 may be any film as long as it has an appropriate mechanical strength and can be easily formed by a known thin film process (CVD method, thermal oxidation method, etc.). Etc. are suitable. On the first main surface 10 </ b> A of the substrate 10, the above-described infrared detecting temperature sensing element 20 connected to the bridge, the reference temperature sensing element 30, and the resistance elements 40 and 50 are formed via an insulating film 70. . Further, a protective film 80 is formed to cover the infrared detecting temperature sensing element 20 and the reference temperature sensing element 30 and shield them from the outside air. The material of the protective film 80 may be an insulating film having moderate durability, and is preferably the same as the material of the insulating film 70, for example. By doing so, since the insulating films covering the periphery of the infrared detecting temperature sensing element 20 and the reference temperature sensing element 30 are all made of the same material, the temperature distribution around the temperature sensing elements 20 and 30 becomes uniform. The temperature detection accuracy is improved.

  An infrared ray absorbing film 91 for absorbing infrared rays radiated from a heat source, converting the light energy into heat, and transferring the heat to the infrared detecting temperature sensitive element 20 is provided with an infrared detecting feeling through the protective film 80. The film is formed so as to cover at least a part of the temperature element 20. As a material of the infrared absorption film 91, for example, a material that efficiently absorbs infrared rays having a wavelength of 4 μm to 10 μm is preferable, a black body material such as Au black or Pt black, or a resin having high infrared absorption efficiency such as polyimide is preferable. is there. However, when the protective film 80 is a thin film (for example, a silicon oxide film) excellent in infrared absorption efficiency, the infrared absorption film 91 is not necessarily provided, and the protective film 80 itself may function as an infrared absorption film. Good. In addition, an infrared reflecting film 92 for reflecting the infrared rays radiated from the heat source and preventing the heat quantity of the infrared rays from being transferred to the reference thermosensitive element 30 is provided at least on the reference thermosensitive element 30 via the protective film 80. The film is formed so as to cover a part. The material of the infrared reflection film 92 may be a thin film having an appropriate infrared reflectance, and for example, a metal material such as aluminum (Al), gold (Au), or platinum (Pt) is suitable.

  A cavity 11 is formed on the substrate 10 corresponding to the position where the infrared sensing temperature sensing element 20 is disposed, and a cavity 12 is formed corresponding to the position where the reference temperature sensing element 30 is disposed. Yes. The cavities 11 and 12 are concave portions that are recessed into the substrate from the second main surface 10B side toward the first main surface 10A side, and have a thin portion 71 that is thinner than the maximum thick portion 13 of the substrate 10. doing. In other words, the infrared detecting temperature sensing element 20 and the reference temperature sensing element 30 have a membrane structure formed in the thin portion 71 of the substrate 10 having a small heat capacity. According to the membrane structure, the sensitivity characteristic can be improved because it can react sensitively even to a small amount of heat. In order to form the cavities 11 and 12, for example, the substrate 10 is made to the second main surface 10B by reactive ion etching such as D-RIE method using a fluoride-based gas or wet etching using an alkaline solution. Deeper in the vertical direction. Of course, it is only necessary to etch the first main surface 10A as a result even if deep etching is performed at an angle. For convenience of explanation, FIG. 2 illustrates the case where the thin portion 71 is formed only by the insulating film 70, but the present embodiment is not limited to this, for example, a portion of the substrate 10. And the insulating film 70 formed thereon may be combined. Alternatively, the thin portion 71 may be formed of an etching stop layer or the like formed in the process of etching the substrate 10. The insulating film 70 may be formed in a hollow state on the air gap provided in the substrate 10. The heat transfer paths between the infrared sensing temperature sensing element 20 and the reference temperature sensing element 30 and the external environment are preferably symmetrical in terms of heat conduction, and the cavities 11 and 12 have the same shape and size. It is preferable that However, in this embodiment, the cavities 11 and 12 are not essential and may be omitted. In particular, the reference thermosensitive element 30 may be designed so that the infrared light receiving sensitivity is somewhat dull according to the specifications, and therefore, only the cavity 12 can be omitted.

  The resistance elements 40 and 50 include resistance adjustment units 41 and 51, respectively. The resistance adjusters 41 and 51 are parts made of resistors whose resistance can be adjusted according to their cutting states. For example, as shown in FIG. 1, a frame-like connection resistor formed by connecting a plurality of frame-like resistors. It is structured as a body. A part of the frame-shaped connecting resistor is melted, scattered, or ablated by, for example, laser irradiation heat, and cut into pieces to obtain a predetermined discrete value (digital value). Value) can be adjusted step by step. The material of the resistance elements 40 and 50 is preferably a material having a small temperature dependency of the change in resistance value. For example, a nickel chromium alloy (NiCr) is preferable. In addition, after the temperature sensing element 20 for infrared detection, the reference temperature sensing element 30, and the resistance elements 40 and 50 are formed on the insulating film 70, the resistance adjusting unit 41 is formed at a stage before the protective film 80 is formed. , 51 may be adjusted by partial cutting, or the infrared detecting temperature sensing element 20, the reference temperature sensing element 30, and the resistance elements 40, 50 are formed on the insulating film 70, and further the resistance After the protective film 80 is formed so that the adjustment parts 41 and 51 are exposed, resistance adjustment is performed by partial cutting of the resistance adjustment parts 41 and 51, and then the resistance adjustment parts 41 and 51 are protected. You may coat with 80.

  At least one of the plurality of raised electrodes (any one of the output terminals 61 and 62 or the common terminals 63 and 64) is one of the two temperature sensitive films 21 and 31, and the two resistance adjusting portions 41. , 51 is preferably formed between them. According to such an arrangement structure, since the scattering of the cutting residue generated when the resistance adjusting portions 41 and 51 are partially cut by laser trimming is shielded by the raised electrode, the cutting residue in a high temperature state is removed from the temperature sensitive element. It is possible to reduce the possibility of being attached to 10, 20 or the vicinity thereof and damaging the element structure, and to improve the sensitivity of the temperature sensor 100. Further, it is preferable that the distance between the resistance adjusting units 41 and 51 and the temperature sensitive elements 20 and 30 is long. For example, the resistance adjusting units 41 and 51 are preferably formed at the end of the substrate 10. Similarly, the frame-like connecting resistor for connecting the frame-like resistors is preferably formed on the end side of the substrate 10 in the resistance adjusting portions 41 and 51 as well. Furthermore, it is preferable that the cut portions of the resistance adjusting portions 41 and 51 are on the end portion side of the substrate 10 opposite to the temperature sensitive elements 20 and 30 side of the frame-shaped connecting resistor. Further, the presence of the protective film 80 that covers the substrate 10 is more effective in shielding the cutting residue scattered from the resistance adjusting portions 41 and 51.

[Experimental Example 1]
One temperature sensor (the former is referred to as sample No. 1 and the latter as sample No. 2) is manufactured in each of the peripheral portion and the central portion of the same silicon wafer. The target value of the DC resistance value of each of the infrared detecting temperature sensing element 20, the reference temperature sensing element 30, and the resistance elements 40 and 50 was set to 33 kΩ. The silicon wafer used in the experiment has variations in characteristics, and the sample No. In the temperature sensor 1, the direct-current resistance values of the infrared detecting temperature sensing element 20, the reference temperature sensing element 30, and the resistance elements 40 and 50 matched the target values. In the temperature sensor 2, the resistance values of the infrared sensing temperature sensing element 20, the reference temperature sensing element 30, and the resistance elements 40 and 50 were 32 kΩ, 32 kΩ, 30 kΩ, and 31 kΩ. These resistance values are measured by measuring the height from the surface opposite to the substrate 10 of the insulating film 70 of the nickel chrome alloy, the temperature sensing element 20 for infrared detection, the reference temperature sensing element 30, and the resistance elements 40 and 50. The film thickness of the resistance elements 40 and 50 is set to 100 nm for 100 nm), the output terminals 61 and 62, and the common terminal 63 (the terminals 61, 62, and 63 from the surface opposite to the substrate 10 of the insulating film 70). (The height was 1000 nm) was formed on the insulating film 70 and before the protective film 80 was formed. Next, sample no. 1, No. 1 Sample No. 2 having the same DC resistance value as each of the temperature sensors 2 and having the protective film 80 formed thereon. 3, No. 4 temperature sensors were prepared, and the difference in output voltage (sensor signal) when the temperature was changed under the same conditions was confirmed. It has been confirmed in advance that the DC resistance value does not change depending on the presence or absence of the protective film 80. Sample No. 3, No. 4 was irradiated with white light, and a voltage of 5 V was applied between the common terminals 63 and 64. The output voltages of the No. 3 and No. 4 temperature sensors were 100 mV and 60 mV, respectively. Therefore, sample no. When resistance adjustment was performed by partially cutting the resistance adjustment portions 41 and 51 of the temperature sensor 2, each resistance value of the resistance elements 40 and 50 was 32 kΩ, and the sensor output was measured after forming the protective film. However, the sensor output improved to 99 mV.

[Experiment 2]
Sample No. Five temperature sensors were prepared. Sample No. The temperature sensor of No. 5 does not have the output terminals 61 and 62 and the common terminal 63, so that the sample No. This is different from the temperature sensor 2 and common in the remaining points. Sample No. When resistance adjustment was performed by partially cutting the resistance adjustment portions 41 and 51 of the temperature sensor 5, each resistance value of the resistance elements 40 and 50 was 32 kΩ, and the sensor output was measured after forming the protective film. However, the sensor output improved to 99 mV. Each DC resistance value was measured with the probe directly applied to the individual electrodes 65 and 66. Sample No. When 100 samples of the same temperature sensor as 5 were prepared and the same experiment was performed, there were 3 samples whose sensor output did not reach 80 mV. Therefore, when the sample was observed, it was found that the cutting residue of the resistance adjusting portions 41 and 51 was attached to a part of the membrane structure. Similarly, sample no. When the resistance adjustment of 100 samples was performed in No. 2, there was no phenomenon that the cutting residue of the resistance adjusting portions 41 and 51 adhered to the membrane structure, and therefore the resistance adjusting portions 41 and 51 were partially cut by laser tremming. It is considered that the scattering of the cutting residue sometimes generated is shielded by the output terminals 61 and 62 and the common terminal 63.

[Experiment 3]
Sample No. 6-No. Nine temperature sensors were prepared. Sample No. 6-No. 9, the output terminals 61 and 62 and the common terminal 63 have a height from the surface of the insulating film 70 (the surface opposite to the substrate 10 of the insulating film 70) of 100 nm, 200 nm, and 500 nm, respectively. Sample No. 1 in that it is 1500 nm. This is different from the temperature sensor 2 and common in the remaining points. Sample No. 7-No. In the temperature sensor No. 9, the phenomenon that the cutting residue of the resistance adjusting portions 41 and 51 adheres to a part of the membrane structure was not observed. In the temperature sensor No. 6, such a phenomenon was observed at a rate of 1 sample per 100 samples. From this experimental result, it was found that the higher the output terminals 61 and 62 and the common terminal 63, the higher the effect of shielding the scattered cutting residue.

[Experimental Example 4]
Sample No. Ten temperature sensors were prepared. Sample No. In the temperature sensor No. 10, the resistance adjusting unit 51 is formed at a position 90 (see FIG. 1) where the output terminals 61 and 62 and the common terminal 63 are not formed between the temperature sensitive elements 20 and 30 and the resistance adjusting unit 51. Sample No. This is different from the temperature sensor 2 and common in the remaining points. Sample No. When resistance adjustment was performed by partially cutting the resistance adjustment portions 41 and 51 of the ten temperature sensors, the resistance values of the resistance elements 40 and 50 were 32 kΩ, and the sensor output was improved to 99 mV. However, sample no. When 100 samples of the same temperature sensor as 10 were prepared and the same experiment was performed, it was found that the cutting residue of the resistance adjusting portions 41 and 51 was attached to a part of the membrane structure for 8 samples. . This is because the output terminals 61 and 62 and the common terminal 63 are not provided between the resistance adjustment unit 51 and the temperature sensitive elements 20 and 30, and there is nothing that shields the cutting residue scattered from the resistance adjustment unit 51. It is thought that. In addition, since the distance between the resistance adjustment unit 51 and the temperature sensitive elements 20 and 30 is short, there is a possibility that the heat generated during laser tremming has some influence on the membrane structure of the temperature sensitive elements 20 and 30.

[Experimental Example 5]
Sample No. Eleven temperature sensors were prepared. Sample No. 11 temperature sensors 20 and 30 and resistance elements 40 and 50 are formed on a substrate 10, and a protective film 80 is further formed on the entire surface of the substrate. Thereafter, output terminals 61 and 62 and a common terminal 63 are formed. , 64 and the resistance adjusting portions 41, 51 are etched so that the protective film 80 is exposed, and subsequently, output terminals 61, 62 and common terminals 63, 64 are formed. Sample No. Each DC resistance value of the temperature sensor No. 11 is sample No. It was the same as each DC resistance value of temperature sensor No. 2. Sample No. When resistance adjustment was performed by partially cutting the resistance adjustment portions 41 and 51 of the 11 temperature sensors, the resistance values of the resistance elements 40 and 50 were 32 kΩ, and the sensor output was improved to 99 mV. Moreover, the cutting residue of the resistance adjustment parts 41 and 51 did not adhere to the membrane structure. From this result, it has been found that the protective film 80 is effective in shielding the cutting residue scattered from the resistance adjusting portions 41 and 51.

[Experimental Example 6]
Sample No. Twelve temperature sensors were prepared. Sample No. In the temperature sensor No. 12, the temperature sensitive elements 20 and 30 and the resistance elements 40 and 50 are formed on the substrate 10, and thereafter the output terminals 61 and 62 and the common terminals 63 and 64 are not formed, and the film thickness is 400 nm. The protective film 80 is formed on the entire surface of the substrate, and the protective film 80 is etched so that the resistance adjusting portions 41 and 51 are exposed. Sample No. Each DC resistance value of the temperature sensor of No. 12 is sample No. It was the same as each DC resistance value of temperature sensor No. 2. Sample No. When the resistance adjustment portions 41 and 51 of the 12 temperature sensors were partially cut to adjust the resistance, the resistance values of the resistance elements 40 and 50 were 32 kΩ, and the sensor output was improved to 99 mV. Moreover, the cutting residue of the resistance adjustment parts 41 and 51 did not adhere to the membrane structure. From this result, it has been found that the protective film 80 is effective in shielding the cutting residue scattered from the resistance adjusting portions 41 and 51.

  The heat detection device according to the present invention can be applied to use for correcting variations in resistance values of resistance elements.

DESCRIPTION OF SYMBOLS 10 ... Board | substrate 20 ... Infrared sensing temperature sensing element 30 ... Reference temperature sensing element 40, 50 ... Resistance element 41, 51 ... Resistance adjustment part 61, 62 ... Output terminal 63, 64 ... Common terminal 80 ... Protective film 100 ... Temperature Sensor

Claims (4)

A temperature sensing element for detecting the amount of heat from the heat source;
A temperature sensing element for detecting the amount of heat in the ambient atmosphere to compensate the temperature of the temperature sensing element;
A first resistance element having a first resistance adjustment unit capable of adjusting a resistance according to a cut state, one end of which is connected to the first output terminal and the other end is connected to the second common terminal;
A second resistance element having a second resistance adjustment unit capable of adjusting the resistance according to the cut state, one end of which is connected to the second output terminal and the other end is connected to the front second common terminal; With
The sensing temperature sensing element is connected to a first output terminal and a first common terminal, and the reference temperature sensing element is connected to a second output terminal and the first common terminal,
The sensing temperature sensing element , the reference temperature sensing element, the first resistance element, and the second resistance element are formed on the same substrate,
The first temperature sensor is formed between one of the sensing temperature sensing element or the reference temperature sensing element and either the first resistance adjusting unit or the second resistance adjusting unit. At least one of the output terminal and the second output terminal is configured such that the first resistor element and the second resistor extend in a direction different from a direction in which the first resistance adjustment unit extends. A thermal detection device formed inside the substrate from the second resistance element extending in a direction different from a direction in which the resistance adjusting unit extends. The heat detection device according to claim 1,
The first resistance element, the second resistance element, the first resistance adjustment unit, the second resistance adjustment unit, the first output terminal, the second output terminal, and the first common terminal And the area | region which projected the said 2nd common terminal on the said board | substrate surface does not have an overlap, The thermal detection device. The thermal detection device according to claim 1 or 2,
The direction in which the first resistance adjustment portion extends and the direction in which the first resistance element extends are orthogonal to each other, and the direction in which the second resistance adjustment portion extends and the second resistance element extend. A thermal detection device that is orthogonal to the existing direction. The heat detection device according to claim 1,
Said 1st resistance adjustment part and said 2nd resistance adjustment part are heat sensing devices which are frame-shaped connection resistors.

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