JPH10318831A - Pyroelectric infrared sensor and infrared camera provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pyroelectric infrared sensor which is suited to downsizing without shielding plate and driving motor for chopper, and is excellent in workability and productivity because of integrated production. SOLUTION: This infrared sensor is provided with a semiconductor substrate 1 made of conductive n-type silicon, a substrate insulation layer 10 laminated thereon, a spacer layer 9 formed on the specified part around the substrate insulation layer 10, an insulation layer 3 fixed on the spacer layer 9, an operating part 4 which is formed by notching the insulation layer 3 and whose both ends are connected to the insulation layer 3, a clearance part 2 formed between the operating part 4 and substrate insulation layer 10, a first electrode part 5 formed on the upper surface of the operating part 4, an infrared ray detection element 6 formed on the upper surface of the first electrode 5, a second electrode 7 formed on the infrared ray detection element 6, and a third electrode 8 laminated on the rear surface of the semiconductor substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pyroelectric infrared sensor for detecting infrared rays by utilizing the pyroelectric effect of a pyroelectric body, and an infrared ray for condensing infrared rays into a pyroelectric infrared sensor and detecting the infrared rays. About the camera.

[0002]

2. Description of the Related Art In recent years, a pyroelectric infrared sensor can detect an object and measure a temperature without contact, so that various switches for a security system, for lighting, for automatic washing of a toilet, and the like,
It is widely used in air conditioner indoor temperature control and industrial measurement fields.

The pyroelectric infrared sensor includes ferroelectric ceramics such as lead zirconate titanate-based ceramics, single crystals such as lithium tantalate, and organic materials such as polyvinylidene fluoride. This is a sensor utilizing a pyroelectric effect in which surface charges are generated. A pyroelectric infrared sensor converts incident infrared light into heat and converts it into an electric signal by a pyroelectric effect. Since the detection signal due to the pyroelectric effect is a differential signal, when detecting a stationary object, it is necessary to forcibly change the amount of infrared light incident on the infrared detection element. As means for forcibly changing the amount of infrared light, Japanese Patent Application Laid-Open No. Hei 6 (1999) discloses a method in which a shielding plate is provided in front of a pyroelectric infrared sensor and a chopper mechanism for shielding or detecting incident infrared light at a certain period is provided. -21
No. 3,714, and JP-A-6-102888.

[0004]

However, the above-mentioned Japanese Patent Application Laid-Open No. 6-102888 and Japanese Patent Application Laid-Open No. 6-213714.
In the pyroelectric infrared sensor disclosed in Japanese Patent Application Laid-Open Publication No. H11-27139, since the shielding plate is driven by a mechanical driving method, the moving space of the shielding plate on the front surface of the infrared detection unit and the contact between the shielding plate and the infrared detection unit do not contact each other. There is a problem in that space is required, and no matter how small the infrared detection unit is, the chopper unit cannot be downsized and the pyroelectric infrared sensor itself cannot be downsized. In addition, there is a problem that work such as installation of a shield plate and a drive motor is complicated, requires a large number of production steps, and lacks production students. Furthermore, the drive motor is a heating element, and has a problem that the heat component increases the noise component of the infrared detection unit.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and provides a pyroelectric infrared sensor which is suitable for downsizing and which is excellent in workability and productivity in integrated production without using a shield plate for a chopper and a driving motor. The purpose is to do.

[0006]

In order to solve the above-mentioned problems, a pyroelectric infrared sensor according to the present invention comprises a conductive substrate,
A substrate insulating layer laminated on the substrate, a spacer layer formed in a predetermined portion around the substrate insulating layer, an insulating layer fixed on the spacer layer, and a cutout formed in the insulating layer. And an operating portion connected to the insulating layer at both ends, a gap formed between the operating portion and the substrate insulating layer, a first electrode portion formed on an upper surface of the operating portion, and An infrared detecting element formed on the upper surface of one electrode part, a second electrode part formed on the infrared detecting element, and a third electrode part laminated on the back surface of the substrate are provided.

[0007] With this configuration, there is an effect that even if an infrared ray having no change in intensity due to the contact operation of the operating section with the substrate insulating layer can be detected, the infrared ray can be detected. As a result, since the shield plate and the driving motor are used, it is possible to reduce the size of the work and to increase the productivity by reducing the number of work steps.

Further, the infrared camera according to the present invention has a function of providing a small and high-performance pyroelectric infrared sensor at a lens and a focal position of the lens.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pyroelectric infrared sensor according to a first aspect of the present invention includes a conductive substrate, a substrate insulating layer laminated on the substrate, and a predetermined portion such as a periphery of the substrate insulating layer. A spacer layer formed in the portion, an insulating layer fixed on the spacer layer, an operating portion formed by cutting out the insulating layer and connected to the insulating layer at both ends, the operating portion and the substrate A gap formed between the insulating layer, a first electrode formed on the upper surface of the operating section, an infrared detecting element formed on the upper surface of the first electrode, and a first electrode formed on the infrared detecting element; And a third electrode unit laminated on the back surface of the substrate. This allows the operating section to detect even incident infrared light with no change in intensity due to the contact operation with the substrate insulating layer, eliminating the need for a chopper shield plate and a drive motor to cut off infrared light, and a pyroelectric infrared sensor. Has the effect of reducing the size.

According to a second aspect of the present invention, in the pyroelectric infrared sensor according to the first aspect, a plurality of strip-shaped operation units are formed by cutting the central portion of the insulating layer in parallel. And a connection part independently connected to the first electrode part and the second electrode part of each of the operation unit parts. This makes it possible to radiate heat of each infrared detecting element at any time by making the contact operation of each of the plurality of operation unit portions and the substrate insulating layer independent, so that the combination makes it possible to receive infrared light with no enhanced change. This also has the effect of eliminating the need for a chopper shield plate and a drive motor for cutting off the infrared rays and making it possible to reduce the size of the multi-element type pyroelectric infrared sensor.

According to a third aspect of the present invention, there is provided a pyroelectric infrared sensor according to the first aspect, wherein the operating portion is formed by cutting a peripheral portion of the insulating layer except for a central portion in a shape of a letter or an arc. A plurality of operation support portions formed in the above-mentioned manner, and one or a plurality of plate-like operation unit portions formed in a polygon, such as a square, a circle, an ellipse, etc., connected to the other end of each of the operation support portions. And a connection section independently connected to the first electrode section and the second electrode section of each of the operation unit sections. As a result, even when the flat operation unit is in contact with the substrate insulating layer, it is possible to detect even an incident infrared light having no change in intensity. Therefore, a chopper shield plate for cutting off the infrared light and a driving motor are unnecessary, and the focus is not required. This has the function of enabling the electronic infrared sensor to be downsized.

According to a fourth aspect of the present invention, there is provided a pyroelectric infrared sensor according to any one of the first to third aspects, wherein the substrate is formed of a silicon semiconductor. Thereby, it is possible to detect even an infrared ray incident with no change in intensity. Since the substrate is formed of a silicon semiconductor, the substrate can be manufactured by an oxidation method, an etching method, or a bonding method, and a thin film forming process is not required, thereby significantly reducing the number of production steps. In addition, since the operation section is formed of a silicon semiconductor, it has an effect that reliability can be improved.

According to a fifth aspect of the present invention, in the pyroelectric infrared sensor according to any one of the first to fourth aspects, the substrate is formed of a P-type silicon semiconductor, and the spacer layer is formed of an n-type semiconductor. It has the structure formed by. Accordingly, there is an effect that an independent contact operation to the substrate insulating layer can be manufactured by a simple manufacturing method so that even the infrared ray incident with no change in intensity can be detected.

According to a sixth aspect of the present invention, there is provided a pyroelectric infrared sensor according to the first or the second aspect, further comprising a fourth electrode portion formed on each of the opposing surfaces of the operation portion of the substrate. doing. Thereby, the operation unit for detecting even the incident infrared light with no change in intensity has an effect of enabling an independent contact operation to the substrate insulating layer.

According to a seventh aspect of the present invention, in the pyroelectric infrared sensor according to the sixth aspect, a voltage is applied to the fourth electrode portion, and each of the operation units is independently contacted with the substrate insulating layer. It has a configuration provided with a connection portion to be made. Accordingly, the operation for detecting even the incident infrared light with no change in intensity has an effect that the substrate operation unit can perform an independent contact operation with the substrate insulating layer.

According to an eighth aspect of the present invention, there is provided an infrared camera having a configuration including a lens and the pyroelectric infrared sensor according to any one of the first to seventh aspects disposed in a focal range of the lens. doing. This has the function of detecting the infrared image with high accuracy without cooling the sensor.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. (Embodiment 1) FIG. 1 is a schematic perspective view of a main part of a pyroelectric infrared sensor according to Embodiment 1 of the present invention.
FIG. 2 is a conceptual sectional view of a main part of the pyroelectric infrared sensor according to Embodiment 1 of the present invention.

In FIG. 1 and FIG. 2, a semiconductor substrate 1 made of n-type silicon, an operation unit 4 made of a silicon oxide strip-shaped operation unit, and the operation unit 4 are formed of the n-type silicon. A gap portion 2 that thermally insulates from the semiconductor substrate 1, an insulating layer 3 that insulates the wiring (not shown) from the n-type silicon semiconductor substrate 1, an infrared detection element 6, and a signal from the infrared detection element 6 A first electrode unit 5 and a second electrode unit 7, a third electrode unit 8 provided on the back surface of the semiconductor substrate 1 made of n-type silicon, a spacer layer 9 for securing a gap,
And a substrate insulating layer 10 made of a thermal oxide film of silicon.

The method of manufacturing the pyroelectric infrared sensor according to the first embodiment configured as described above will be described below.

FIGS. 3A to 3E and FIGS. 4F to 4F.
(J) is an essential part cross sectional view of a step showing a method for manufacturing a pyroelectric infrared sensor in Embodiment 1 of the present invention.

First, as shown in FIG. 3A, a p-type crystal having a crystal orientation plane 100 as an upper surface and a spacer layer 9 of n-type silicon semiconductor formed on one side with a thickness of 4 μm is formed.
A silicon semiconductor auxiliary substrate 11 is prepared, and a second insulating film 10a is formed on the outermost surface by a thermal oxidation method with a thickness of 0.5 μm. As shown in FIG. 3B, a semiconductor substrate 1 made of n-type silicon having a crystal orientation plane 100 as an upper surface is prepared, and a second insulating film 10b is formed on the outermost surface by thermal oxidation to a thickness of 0.5 μm. Formed. Next, as shown in FIG. 3C, the second insulating films 10a and 10b on the outermost surface are bonded by a silicon fusion bonding method to form the substrate insulating layer 10 as an integrated layer. Next, by removing the p-type silicon semiconductor auxiliary substrate 11 by an electrochemical etching method in FIG. 3A, the etching is automatically stopped on the surface of the spacer layer 9, and the spacer layer is formed to be exposed on the outermost surface. .
Next, as shown in FIG. 3E, an insulating layer 3 is formed to a thickness of 2 μm on the exposed surface of the spacer layer 9 by a thermal oxidation method. The oxide film on the back surface of the n-type silicon semiconductor substrate 1 is removed by wet etching using buffered hydrofluoric acid or the like to expose the silicon back surface. Next, FIG.
A metal film is formed to a thickness of 0.2 μm on the exposed silicon back surface by a deposition method as shown in FIG. A pattern is formed on the surface of the insulating layer 3 by a photolithography method, and the insulating layer 3 is subjected to wet etching using buffered hydrofluoric acid or the like.
The insulating layer 3 thus etched as shown in FIG. 4G is separated into an intermediate product of the operation section 4 and the insulating layer 3.

Next, as shown in FIG.
Of the first electrode portions 5, 0.
The infrared detecting element 6 having a thickness of 5 μm and the second electrode portion 7 having a thickness of 0.2 μm are sequentially laminated by a screen printing method or the like. In addition, instead of the screen printing method, the first electrode portion 5 having a thickness of 0.2 μm, the infrared detecting element 6 having a thickness of 0.5 μm, and the second electrode portion 7 having a thickness of 0.2 μm are sequentially laminated by a sputtering method or a vapor deposition method. It may be manufactured by pattern formation by photolithography. FIG.
In the state of (h), etching is performed with a potassium hydroxide solution, a nitric acid solution or the like to remove the spacer layer 9 below the intermediate product of the operation unit 4, and as shown in FIG.
And a gap 2 is formed. Finally, as shown in FIG. 4 (j), the silicon window material 14 is made of an oxide film 1 made of silicon oxide or the like.
After adhering to the upper part of the insulating layer 3 through the inside 3, the inside is filled with dry nitrogen gas and sealed.

Embodiment 1 manufactured as described above
Hereinafter, the operation of the pyroelectric infrared sensor will be described with reference to the drawings. FIGS. 5A and 5B are cross-sectional views of main parts showing the operation of the pyroelectric infrared sensor according to the first embodiment.

First, when the first electrode unit 5 is grounded and a positive voltage of, for example, 30 V is applied to the third electrode unit 8, the operation unit 4 is activated.
Is attracted to the semiconductor substrate 1 made of n-type silicon by electrostatic force, the vicinity of the connection with the insulating layer 3 at both ends of the operation section 4 is elastically deformed, and the operation section 4 other than the vicinity of the connection comes into contact with the substrate insulating layer 10. . When the voltage applied to the third electrode unit 8 is set to 0 V, which is the same potential as the first electrode unit, the electrostatic force on the upper surface of the semiconductor substrate 1 made of n-type silicon disappears and is restored to the initial state by the restoring force of the operation unit 4. . That is, by switching the voltage of the third electrode unit 8 between 0 V and 30 V, the center of the operation unit 4 can be brought into contact with or separated from the substrate insulating layer 10. The temperature of the infrared detection element 6 becomes the same as that of the semiconductor substrate 1 made of n-type silicon by the contact operation of the operation section 4 described above.

The infrared detecting element 6 is formed of a thin film, has a heat capacity much smaller than that of the semiconductor substrate 1 made of n-type silicon, and the temperature of the infrared detecting element 6 is different from that of the semiconductor substrate 1 made of n-type silicon. In this case, the semiconductor substrate 1 is cooled or heated to the temperature of the semiconductor substrate 1 made of n-type silicon. Here, when infrared rays 12 are incident on the upper surface of the second electrode portion 7 from the vertical direction, the infrared detecting element 6 is heated and rises above the semiconductor substrate 1 made of n-type silicon and the ambient temperature. When a voltage of 30 V is applied to the third electrode section 8 in the above state, the operating section 4 comes into contact with the upper surface of the semiconductor substrate 1 made of n-type silicon, and the operating section 4 is transferred from the infrared detecting element 6 to the semiconductor substrate 1 made of n-type silicon. The heat moves through the contact portion, and the infrared detecting element 6 is cooled, and the temperature of the infrared detecting element 6 becomes almost uniform with the temperature of the semiconductor substrate 1 made of n-type silicon. Therefore, by controlling the voltage of the third electrode unit 8, the temperature of the infrared detecting element 6 heated by the infrared radiation from the target can be changed to the initial temperature without the infrared radiation from the target. .

(Embodiment 2) FIG. 6 is a cutaway perspective view of a principal part of a pyroelectric infrared sensor according to Embodiment 2 of the present invention. FIG. 7 is a conceptual sectional view of a principal part of a pyroelectric infrared sensor according to a second embodiment of the present invention, and FIG. 8 is a conceptual plan view of a principal part of the pyroelectric infrared sensor according to the second embodiment of the present invention. As shown in FIGS. 6 to 8, the pyroelectric infrared sensor according to the second embodiment includes a semiconductor substrate 1 made of n-type silicon, an operation unit 42 formed in a square shape at the center of the semiconductor substrate 1, The motion support portion 3 formed by cutting out in a U-shape or an arc shape so as to connect the periphery of the motion unit portion 42
4. a gap 2 for thermally insulating the operation unit 42 from the n-type silicon semiconductor substrate 1; an insulating layer 3 for insulating the n-type silicon semiconductor substrate 1 from wiring (not shown); An infrared detecting element 6; a first electrode section 5 and a second electrode section 7 for extracting signals from the infrared detecting element 6; a third electrode section 8 provided on the back surface of the semiconductor substrate 1 made of n-type silicon; 34, a spacer layer 9 for holding the operation unit 42, and a substrate insulating layer 10 made of a silicon oxide film.

A method of manufacturing the pyroelectric infrared sensor according to the second embodiment configured as described above will be described below. Up to the formation of the third electrode portion 8, it is manufactured in the same process as in the first embodiment. Operation support unit 34 and operation unit unit 4
2 is produced as follows. First, a pattern is formed on the surface of the insulating layer 3 by a photolithography method. The insulating layer 3 is subjected to wet etching using buffered hydrofluoric acid or the like. The etched insulating layer 3 becomes the operation support portion 34.
Intermediate product, the intermediate product of the operation unit 42 and the insulating layer 3
Is separated into The first electrode portion 5, the infrared detecting element 6, and the second electrode portion 7 are sequentially laminated on the surface of the intermediate product of the operation unit 42 by a screen printing method. The intermediate portion of the operation support portion 34 and the spacer layer 9 below the operation unit portion 42 are etched and removed with a potassium hydroxide solution or a nitric acid solution to remove the operation support portion 34, the operation unit portion 42, and the gap 2. Form. The patterning shape of the operation support portion 34 and the operation unit portion 42 is different from that of the first embodiment, and has a spiral shape as shown in FIG. By increasing the length of the operation support section 34, the operation unit section 42 can be brought into contact with the substrate insulating layer 10 with a small voltage even if the operation support section thickness is large.

The operation unit 42 is one in this embodiment.
Although one is formed, a plurality may be formed. The operation unit 4
The two first electrode portions 5, the infrared detecting element 6, and the second electrode portion 7 may be divided into a plurality of pieces and each may be wired.

(Embodiment 3) FIG. 9 is a conceptual plan view of a principal part of a pyroelectric infrared sensor according to Embodiment 3 of the present invention, and FIG. It is a partial section conceptual diagram. As shown in FIGS. 9 and 10, the pyroelectric infrared sensor according to the second embodiment
A semiconductor substrate 51 made of p-type silicon; an operation unit 4; a gap 2 that thermally insulates the operation unit 4 (4a, 4b, 4c, 4d) from the p-type silicon semiconductor substrate 51; An insulating layer 3 for insulating a wiring (not shown) from a semiconductor substrate 51 made of mold silicon, an infrared detecting element 6, a first electrode section 5 for extracting a signal from the infrared detecting element 6 (6a, 6b, 6c, 6d); The second electrode unit 7 (7a, 7b, 7
c, 7d) The operation unit 4 is located in the lower direction of the operation unit 4 in the same shape as the operation unit 4 and the spacer layer 9 necessary for manufacturing, the substrate insulating layer 10 made of a thermal oxide film of silicon, and the like. , And a fourth electrode portion 52 insulated by the substrate insulating layer 10.

A method of manufacturing the pyroelectric infrared sensor according to the third embodiment having the above-described configuration will be described below with reference to the drawings. 11 (a) to 11 (e), FIG.
(F)-(h) is sectional drawing of the principal part in each manufacturing process which shows the manufacturing method of the pyroelectric infrared sensor in Embodiment 3 of this invention. As shown in FIG. 11B, the crystal orientation plane 1
A semiconductor substrate 5 made of p-type silicon with the 00 surface being the upper surface
A silicon oxide film having a thickness of 1 μm is formed on one surface by a thermal oxidation method. A linear pattern is formed by photolithography, and the silicon oxide film is etched into a predetermined shape by wet etching. Using this silicon oxide film as a mask, an n-type silicon semiconductor electrode 52 is formed on the surface of the p-type silicon substrate 51 by a diffusion method, and the mask of the silicon oxide film is removed by etching. Further, the second insulating film 10b is formed on the outermost surface of the p-type silicon semiconductor substrate 51 by a thermal oxidation method.
Is formed with a thickness of 0.5 μm.

Next, as shown in FIG. 11A, a p-type silicon semiconductor in which a crystal orientation plane 100 is an upper surface and a spacer layer 9 made of an n-type silicon semiconductor is formed on one side with a thickness of 4 μm. An auxiliary substrate 11 is prepared and a second insulating film 10a is formed on the outermost surface of the semiconductor substrate 11 by thermal oxidation.
It is formed with a thickness of 5 μm. Here, as shown in FIG. 11C, these second insulating films 10a and 10b on the outermost surface are bonded by a silicon fusion bonding method.
a and 10b are used as the substrate insulating layer 10 which is an integrated layer. Next, by removing the p-type silicon semiconductor auxiliary substrate 11 by a quadrupole method which is an electrochemical etching method, the etching is automatically stopped at the surface of the spacer layer 9, and FIG.
The spacer layer 9 is exposed on the outermost surface as shown in FIG. Next, as shown in FIG. 11E, the insulating layer 3 is formed with a thickness of 2 μm on the exposed surface of the spacer layer 9 by a thermal oxidation method. Insulating layer 3
A pattern is formed on the surface of the insulating layer 3 by a photolithography method, and the insulating layer 3 is subjected to wet etching using buffered hydrofluoric acid or the like. In this state, the etched insulating layer 3 is separated into an intermediate product of the operation unit 4 and the insulating layer 3 as shown in FIG. Next, as shown in FIG. 12 (g), the 0.2 μm-thick first electrode portion 5 and the 5 μm-thick infrared detecting elements 6 and 0.
The second electrode portions 7 having a thickness of 2 μm are sequentially laminated by a screen printing method. Finally, as shown in FIG. 12 (h), the operation unit 4 and the gap 2 are removed by etching the spacer layer 9 below the intermediate product of the operation unit 4 using a potassium hydroxide solution or a nitric acid solution. Form.

Embodiment 3 manufactured as described above
Hereinafter, the operation of the pyroelectric infrared sensor will be described with reference to the drawings. 13 (a) to 13 (e) are cross-sectional views of main parts showing respective operation steps of the pyroelectric infrared sensor according to the third embodiment. FIGS. 14 (1) to 14 (3) are fourth views of the third embodiment. FIG. 4 is a diagram illustrating a relationship between a voltage application timing to an electrode unit and an output signal of a second electrode unit. First, when the first electrode section 5 is grounded and a positive voltage of, for example, 30 V is applied to the fourth electrode section 52a, the operation unit section 4a is attracted to the fourth electrode section 52 by electrostatic force, and both ends of the operation unit section 4a The vicinity of the connection with a certain insulating layer 3 is elastically deformed, and the operation unit 4 a other than the vicinity of the connection comes into contact with the upper surface of the substrate insulating layer 10.
At this time, if the infrared detecting element 6a has been heated by the incidence of infrared light, the heat is radiated to the semiconductor substrate 51 made of p-type silicon. Next, when a voltage of 0 V is applied to the fourth electrode portion 52a and a positive voltage of, for example, 30 V is applied to the fourth electrode portion 52b, the electrostatic force on the upper surface of the fourth electrode portion 52a disappears, and the central portion of the operation unit 4a is restored. The operation unit 4b is restored to the initial state by a force, and is attracted to the fourth electrode unit 52b by electrostatic force. Unit 4
b contacts the upper surface of the substrate insulating layer 10. At this time, both the infrared detecting elements 6a and 6b
Is incident, the infrared detecting element 6a is heated by the incident infrared light, a positive output signal is generated at the first electrode unit 5 and the second electrode unit 7a, and the infrared detecting element 6b is heated by the incident infrared light. Therefore, heat is radiated to the semiconductor substrate 51 made of p-type silicon, and a negative output signal is generated at the first electrode unit 5 and the second electrode unit 7b. Similarly, as shown in FIG. 14A, the voltages of the fourth electrode portions 52a, 52b, 53c, and 52d are set to 0.
By switching to V and 30V sequentially,
(2) Or it is possible to individually detect the output signals of the infrared detecting elements 6a, 6b, 6c, 6d as shown in FIG. Although the fourth electrode portion is shown as an example made up of an n-type silicon semiconductor, the same can be applied to a case where it is made up of other metal electrodes. Also,
The present invention can be similarly implemented when the number of the infrared detecting elements 6 is increased and the number is arranged in a large number in a plane.

(Embodiment 4) FIG. 15 is a perspective conceptual view of an infrared camera according to Embodiment 4 of the present invention.
FIG. 6 is a conceptual sectional perspective view of an infrared camera according to Embodiment 4 of the present invention. As shown in FIGS. 15 and 16, the infrared camera according to the fourth embodiment has a lens 55 and a main body 5.
6, an infrared detecting element 57, a detecting circuit (not shown), an amplifying circuit, a power supply circuit and the like. Infrared detector 57
Is composed of a detection element in which the above-mentioned infrared sensor is multi-element.

The operation of the infrared camera is as follows.
The image is formed on the infrared detecting element 57 through the sensor and detected by each infrared sensor of the infrared detecting section. The signal is detected by the detection circuit through the wiring, and is amplified by the amplification circuit. Power is supplied to the infrared detection unit, the detection circuit, and the amplification circuit by a power supply circuit.

[0035]

According to the pyroelectric infrared sensor of the first aspect of the present invention, due to the elasticity of the operating section, the operating section receives infrared light with no change in intensity due to the contact operation with the substrate insulating layer. Therefore, a shield plate for a chopper for cutting off infrared rays and a driving motor are not required, and the pyroelectric infrared sensor can be downsized. Since the whole sensor can be constituted by a thin film, the pyroelectric infrared sensor can be formed compactly. Since the number of parts is small, the number of work steps is small and the productivity is excellent. Since there is no heating element such as a drive motor, a noise component of the infrared detection unit can be significantly reduced, and a highly accurate pyroelectric infrared sensor can be obtained.

According to the pyroelectric infrared sensor according to the second aspect of the present invention, in the first aspect, a plurality of strip-shaped operation units formed by cutting out the central portion of the insulating layer in parallel at the operation portion. And a connection part independently connected to the first electrode part and the second electrode part of each operation unit part, so that a plurality of operation units and the contact operation of the substrate insulating layer are further provided. Is independent, heat can be radiated from each infrared detecting element at any time. Therefore, even if infrared light having no intensity change can be detected by the combination, the detection efficiency can be significantly increased. Further, since the structure is simple, productivity can be improved.

According to a third aspect of the present invention, there is provided a pyroelectric infrared sensor according to the first aspect, wherein the operating portion is formed by cutting a peripheral portion of the insulating layer except for a central portion into a V-shape or an arc shape. A plurality of operation support portions, one or more plate-like operation unit portions formed in a polygon, such as a square, a circle, an ellipse, etc., connected to the other end of each operation support portion; Since the unit has a connection portion which is independently connected to the first electrode portion and the second electrode portion of the unit portion, the contact operation of the operation unit portion with the substrate insulating layer makes it possible to receive infrared light with no change in intensity. Even if there is, detection can be performed, so that the detection efficiency can be significantly increased.

According to a fourth aspect of the present invention, there is provided a pyroelectric infrared sensor according to any one of the first to third aspects, wherein the substrate is formed of a silicon semiconductor. It can improve productivity and can be mass-produced at low cost. In addition, since the silicon is crystalline, the operating portion has excellent mechanical strength and high reliability can be obtained.

According to a fifth aspect of the present invention, there is provided a pyroelectric infrared sensor according to any one of the first to fourth aspects, wherein the substrate is formed of a P-type silicon semiconductor, and the spacer layer is formed of an n-type semiconductor. Therefore, it can be manufactured by a simple manufacturing method, productivity can be improved, and mass production can be performed at low cost.
In addition, the thickness of the operating section and the gap can be accurately controlled.

According to a sixth aspect of the present invention, the pyroelectric infrared sensor according to the first or second aspect further includes a fourth electrode portion formed on each of the opposing surfaces of the operating portion of the substrate. Furthermore, even if the infrared ray having no change in intensity is detected, the operation section for detecting can perform an independent contact operation to the substrate insulating layer, and the detection effect can be enhanced.

According to a seventh aspect of the present invention, in the pyroelectric infrared sensor according to the sixth aspect, a voltage is applied to the fourth electrode portion, and each of the operation units is independently contacted with the substrate insulating layer. In addition, since a connection portion is provided, even if infrared rays having no intensity change can be detected, the operation of the substrate operation portion can perform an independent contact operation with the substrate insulating layer, thereby improving the detection effect. Can be.

The infrared camera according to the eighth aspect of the present invention includes a lens, and the pyroelectric infrared sensor according to any one of the first to seventh aspects, which is disposed in a focal region of the lens. Further, the infrared image can be detected without cooling the sensor. Also, since the pyroelectric infrared sensor is small and compact, the infrared camera can be formed small and compact.

Since a chopper shield plate and a driving motor to be installed on the front surface of the infrared light receiving element are not required, the mounting work and the like can be reduced and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a principal part cutaway of a pyroelectric infrared sensor according to a first embodiment of the present invention.

FIG. 2 is a conceptual cross-sectional view of a main part of the pyroelectric infrared sensor according to the first embodiment of the present invention;

FIG. 3A is a cross-sectional view of a main part in a process showing a method for manufacturing a pyroelectric infrared sensor according to the first embodiment of the present invention; FIG. 3B is a pyroelectric infrared sensor according to the first embodiment of the present invention; (C) is a cross-sectional view of a main part in a step showing a method for manufacturing a pyroelectric infrared sensor according to the first embodiment of the present invention. (D) is a cross-sectional view of a main part in the step of the present invention. Section (e) is an essential part cross-sectional view in a step showing the method for manufacturing the pyroelectric infrared sensor in the first embodiment. (E) is a part cross-sectional view in the step showing the method for manufacturing the pyroelectric infrared sensor in the first embodiment of the present invention.

FIG. 4 (f) is a cross-sectional view of a main part in a step showing a method of manufacturing the pyroelectric infrared sensor according to the first embodiment of the present invention. FIG. 4 (g) is a pyroelectric infrared sensor according to the first embodiment of the present invention. (H) is a cross-sectional view of a main part in a step of a method for manufacturing a pyroelectric infrared sensor according to the first embodiment of the present invention. (I) is a cross-sectional view of a main part in a step of the present invention. Section (j) of a principal part in a step showing a method of manufacturing the pyroelectric infrared sensor according to the first embodiment (j) is a sectional view of a main part in a step showing the method of manufacturing the pyroelectric infrared sensor according to the first embodiment of the present invention.

5A is a sectional view of a main part showing an operation of the pyroelectric infrared sensor according to the first embodiment; FIG. 5B is a sectional view of a main part showing an operation of the pyroelectric infrared sensor according to the first embodiment;

FIG. 6 is a cutaway perspective view of a principal part of a pyroelectric infrared sensor according to a second embodiment of the present invention.

FIG. 7 is a conceptual sectional view of a principal part of a pyroelectric infrared sensor according to a second embodiment of the present invention.

FIG. 8 is a schematic plan view of a main part of a pyroelectric infrared sensor according to a second embodiment of the present invention.

FIG. 9 is a conceptual plan view of a main part of a pyroelectric infrared sensor according to a third embodiment of the present invention.

FIG. 10 is a conceptual cross-sectional view of a main part of a pyroelectric infrared sensor according to a third embodiment of the present invention.

11A is a sectional view of a main part in each step showing a method of manufacturing a pyroelectric infrared sensor according to Embodiment 3 of the present invention. FIG. 11B is a pyroelectric infrared sensor according to Embodiment 3 of the present invention. (C) is a cross-sectional view of a main part in each step showing a method of manufacturing a pyroelectric infrared sensor according to the third embodiment of the present invention. (D) is a cross-sectional view of a main part of the present invention. Sectional cross-sectional view of a principal part in each step showing a method for manufacturing a pyroelectric infrared sensor according to Embodiment 3 (e) is a cross-sectional view of a main part in each step showing a method for manufacturing a pyroelectric infrared sensor according to Embodiment 3 of the present invention.

12 (f) is a cross-sectional view of a principal part in each step showing a method for manufacturing a pyroelectric infrared sensor according to Embodiment 3 of the present invention. FIG. 12 (g) is a pyroelectric infrared sensor according to Embodiment 3 of the present invention. (H) is a cross-sectional view of a main part in each step of the method for manufacturing a pyroelectric infrared sensor according to the third embodiment of the present invention;

13A is a sectional view of a main part showing each operation process of the pyroelectric infrared sensor according to the third embodiment. FIG. 13B is a main part showing each operation process of the pyroelectric infrared sensor according to the third embodiment. Sectional view (c) is a main part cross-sectional view showing each operation process of the pyroelectric infrared sensor according to the third embodiment. (D) is a main part cross-sectional view showing each operation process of the pyroelectric infrared sensor according to the third embodiment. (E) is a fragmentary cross-sectional view showing each operation step of the pyroelectric infrared sensor in Embodiment 3.

14A is a diagram illustrating a relationship between a voltage application timing to a fourth electrode unit and an output signal of the second electrode unit according to the third embodiment. FIG. 14B is a diagram illustrating a relationship between a voltage application timing and a fourth electrode unit according to the third embodiment. The figure which shows the relationship between the voltage application timing and the output signal of a 2nd electrode part in FIG. 3 (3) The figure which shows the relationship between the voltage application timing to a 4th electrode part in Embodiment 3, and the output signal of a 2nd electrode part.

FIG. 15 is a schematic perspective view of an infrared camera according to Embodiment 4 of the present invention.

FIG. 16 is a schematic sectional perspective view of an infrared camera according to Embodiment 4 of the present invention.

[Explanation of symbols]

 Reference Signs List 1 semiconductor substrate made of n-type silicon 2 gap 3 insulating layer 4, 4a, 4b, 4c, 4d operating unit 5, 5a, 5b, 5c, 5d first electrode unit 6, 6a, 6b, 6c, 6d infrared detecting element 7, 7a, 7b, 7c, 7d Second electrode unit 8 Third electrode unit 9 Spacer layer 10 Substrate insulating layer 11 P-type silicon semiconductor auxiliary substrate 12 Infrared ray 13 Silicon oxide film 14 Silicon window material 34 Operation support unit 42 Operation unit unit 51 P-type silicon semiconductor substrate 52, 52a, 52b, 52c, 52d Fourth electrode part 55 Lens 56 Body 57 Infrared detector

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takahiro Omori 1006 Ojidoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. A conductive substrate, a substrate insulating layer laminated on the substrate, a spacer layer formed in a predetermined portion such as a periphery of the substrate insulating layer, and an insulating layer fixed on the spacer layer. A layer, a working part formed by cutting out the insulating layer and connected to the insulating layer at both ends, a gap formed between the working part and the substrate insulating layer, and an upper surface of the working part A first electrode portion formed on the first electrode portion, an infrared detecting element formed on the upper surface of the first electrode portion, a second electrode portion formed on the infrared detecting device, and a third electrode portion laminated on the back surface of the substrate. An pyroelectric infrared sensor comprising: an electrode unit. 2. A plurality of strip-shaped operation units formed by cutting out the center of the insulating layer in parallel with the operation unit, and the first electrode unit and the second electrode of each operation unit. 2. The device according to claim 1, further comprising: a plurality of first electrode portions of each of the operation unit portions; and connection portions independently connected to the plurality of second electrode portions of each of the operation unit portions. 3. Pyroelectric infrared sensor. 3. A plurality of operation supporting portions, each of which is formed by cutting a peripheral portion of the insulating layer except a central portion of the insulating layer into a U shape or an arc shape, and the other end of each of the operation supporting portions. A plurality of plate-like operation units formed in a polygon such as a square, a circle, an ellipse, etc., connected to the unit, and the first unit of each operation unit
An electrode part and the second electrode part, or a plurality of the first electrode parts of each of the operation unit parts and a connection part independently connected to the plurality of the second electrode parts. The pyroelectric infrared sensor according to claim 1, wherein 4. The pyroelectric infrared sensor according to claim 1, wherein said substrate is formed of a silicon semiconductor. 5. The pyroelectric device according to claim 1, wherein said substrate is formed of a P-type silicon semiconductor, and said spacer layer is formed of an n-type semiconductor. Infrared sensor. 6. The pyroelectric infrared sensor according to claim 1, further comprising: a fourth electrode portion formed on each of the opposing surfaces of the operation portion of the substrate. 7. A pyroelectric device according to claim 6, further comprising a connection portion for applying a voltage to said fourth electrode portion and bringing each of said operation unit portions into contact with said substrate insulating layer independently. Type infrared sensor. 8. An infrared camera, comprising: a lens; and the pyroelectric infrared sensor according to claim 1 disposed in a focal area of said lens.