JP2013108970A - Infrared detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared detection device capable of reducing the size.SOLUTION: An infrared detection device 10 includes: an infrared sensor 1 for detecting infrared ray; a package base 2 having an infrared sensor 1 disposed thereon; and a cover 4 which covers the infrared sensor 1 and has a lens 3 for condensing infrared ray onto the infrared sensor 1. The infrared sensor 1 includes: a base substrate 1b having an opening 1f formed at a surface 1aa side; and a thin film 1a supported by the base substrate 1b at the other face 1ab side of the base substrate 1b. The infrared detection device 10 also has an infrared ray detecting section 1e including infrared ray absorbing sections 1c and 1d which are formed at least on the thin film 1a for absorbing the infrared ray. In a thickness direction, the infrared sensor 1 is disposed on the thin film 1a facing to the opening 1f so that at least a part of the infrared ray absorbing sections 1c and 1d absorbs the infrared ray coming through the lens 3. The other face 1ab side of the base substrate 1b is defined as the package base 2 side.

Description

  The present invention relates to an infrared detection device including an infrared sensor.

  Conventionally, infrared detection devices have been used as human sensors for various electronic devices. The infrared detection device has a configuration in which, for example, an infrared sensor is arranged inside a package and the infrared sensor is irradiated with infrared rays through a window provided in the package.

  As an infrared sensor used in the infrared detection device, as shown in FIG. 16, an infrared detection thermopile in which infrared absorbers 120a and 120b and thermocouple patterns 114a and 114b are formed on the front and back surfaces of an insulating substrate 118 is known. (For example, Patent Document 1).

  As shown in FIG. 17, the infrared detection thermopile disclosed in Patent Document 1 includes a plurality of thermocouples 114 each having a thermocouple pattern 114 a composed of a first thermoelectric pattern 110 and a second thermoelectric pattern 112 on the surface of an insulating substrate 118. Connected to and formed.

  Further, as shown in FIG. 18, in the infrared detection thermopile, on the back surface of the insulating substrate 118, the thermocouple pattern 114b is composed of the first thermoelectric pattern 110 and the second thermoelectric pattern 112 similarly to the thermocouple pattern 114a. Thermocouples 114 are connected in series. The infrared detection thermopile has infrared absorbers 120a and 120b and thermocouple patterns 114a and 114b formed on both front and back surfaces of the insulating substrate 118, and the infrared absorbers 120a and 120b on both front and back surfaces are provided at positions where they overlap each other. Note that the infrared detection thermopile is configured such that the side close to the infrared absorbers 120a and 120b is the warm junction 113 and the far side is the cold junction 115.

  In the infrared detection thermopile, one end A of the thermocouple pattern 114 a on the surface of the insulating substrate 118 is connected to one end B of the thermocouple pattern 114 b on the back surface through the first through hole 17 a provided in the insulating substrate 118. In the infrared detection thermopile, the other end C of the thermocouple pattern 114b on the back surface of the insulating substrate 118 is connected to the other end D of the thermocouple pattern 114a on the surface through the second through hole 17b. In the infrared detection thermopile, all the thermocouples 114 on both the front and back surfaces of the insulating substrate 118 are connected in series, and a detection signal is extracted from the signal extraction electrode 128 on the surface to the outside of the package.

  The infrared detection thermopile of Patent Document 1 forms a plurality of thermocouple patterns 114a and 114b connected in series on the back surface of the insulating substrate 118 in the same manner as the front surface side, and increases the number of thermocouples 114 connected. The sensitivity can be increased. The infrared detection thermopile is housed in a package (not shown), and a silicon substrate 116 having an insulating substrate 118 formed on the upper surface is provided on a base on the lower end side of the package to constitute an infrared detection device.

Japanese Utility Model Publication No. 5-43037

  By the way, for example, in order to efficiently irradiate infrared rays with an infrared sensor having a configuration such as that disclosed in Patent Document 1, it is conceivable that the infrared detection device has a configuration in which a lens for condensing infrared rays is provided on the package window. . Thereby, the infrared detection device can be made more highly sensitive.

  However, when the infrared detection device collects infrared rays using a lens, the infrared detection device must be separated from the lens by the focal length of the lens. For this reason, the infrared detection device having a lens has a problem that it is difficult to reduce the size of the entire infrared detection device. In particular, infrared detectors are required to be smaller with the downsizing of electronic devices used, and the structure of the above-described infrared detector is not sufficient, and further improvement in characteristics is required. ing.

  This invention is made | formed in view of the said reason, The objective provides the infrared rays detection apparatus in which size reduction is possible.

  An infrared detection device of the present invention includes an infrared sensor that detects infrared rays, a package base on which the infrared sensor is disposed, and a cover that includes a lens that covers the infrared sensor and collects infrared rays on the infrared sensor. In the detection device, the infrared sensor is provided at least in a base substrate having an opening provided on one surface side, a thin film portion supported by the base substrate on the other surface side of the base substrate, and the thin film portion. An infrared detector having an infrared absorber that absorbs infrared rays, and in the thickness direction, at least a part of the infrared absorber is disposed on the thin film portion facing the opening so as to absorb infrared rays from the lens. The other surface side of the base substrate is the package base side.

  In this infrared detection device, an infrared reflection film that reflects infrared rays from the lens side that is not absorbed by the infrared absorption portion and transmits through the infrared absorption portion to the infrared absorption portion side is provided on the package base side. Is preferred.

  In this infrared detection apparatus, the infrared detection unit includes a first electrode unit provided on the other surface side of the thin film unit and a pyroelectric layer provided on the opposite side of the first electrode unit to the thin film unit side. And a second electrode part provided on the opposite side of the pyroelectric layer from the first electrode part side.

  In the infrared detection device, the infrared sensor includes an infrared transmission film that transmits infrared rays on the one surface side of the thin film portion facing the opening, and the infrared sensor is disposed between the infrared transmission film and the first electrode portion. It is preferable that the infrared transmission film functions as a component constituting the infrared absorption part on the one surface side in the thin film part by providing an optical resonance structure in which light is confined and resonated.

  In this infrared detection device, it is preferable that the infrared sensor is provided with an infrared reflection layer that reflects infrared rays toward the infrared absorption portion on the inner peripheral wall of the opening of the base substrate.

  In this infrared detector, the infrared sensor preferably includes a plurality of the infrared detectors.

  In this infrared detection apparatus, it is preferable that the infrared sensor includes a wall portion that divides the opening portion for each infrared detection portion on the base substrate in correspondence with each of the plurality of infrared detection portions.

  The infrared detection device of the present invention has an effect that it can be further downsized.

1 is a schematic cross-sectional view illustrating an infrared detection device according to a first embodiment. It is explanatory drawing explaining absorption of the infrared rays in an infrared detection apparatus same as the above. It is a schematic sectional drawing which shows the infrared rays detection apparatus of Embodiment 2. It is a schematic plan view of the infrared sensor used for an infrared detection apparatus same as the above. It is a schematic sectional drawing which shows XX of FIG. 4 which shows the principal part of an infrared detection apparatus same as the above. It is explanatory drawing explaining the principal part of another infrared detection apparatus same as the above. It is a schematic sectional drawing which shows another infrared detection apparatus same as the above. It is a schematic sectional drawing which shows the infrared rays detection apparatus of Embodiment 3. It is a schematic sectional drawing which shows the infrared rays detection apparatus of Embodiment 4. FIG. 9 is a schematic cross-sectional view showing an infrared detection device of Embodiment 5. It is a schematic sectional drawing which shows the infrared rays detection apparatus of Embodiment 6. FIG. 10 is a schematic cross-sectional view illustrating an infrared detection device according to a seventh embodiment. It is a schematic sectional drawing which shows another infrared detection apparatus same as the above. It is a schematic sectional drawing which shows the other infrared detection apparatus same as the above. It is a schematic sectional drawing which shows the infrared rays detection apparatus of Embodiment 8. It is sectional drawing of the principal part structure in the conventional thermopile for infrared detection. It is a top view of the principal part structure in the thermopile for infrared detection same as the above. It is a bottom view of the principal part structure in the thermopile for infrared detection same as the above.

(Embodiment 1)
Hereinafter, the infrared detection device 10 of the present embodiment will be described with reference to FIGS. 1 and 2. In addition, the same number is attached | subjected to the same member in the figure.

  As shown in FIG. 1, the infrared detection device 10 of the present embodiment includes an infrared sensor 1 that detects infrared rays and a package base 2 on which the infrared sensor 1 is disposed. The infrared detecting device 10 includes a cover 4 including a lens 3 that covers the infrared sensor 1 and collects infrared rays (see the broken arrow in FIG. 1) on the infrared sensor 1.

  The infrared sensor 1 of the infrared detecting device 10 includes a base substrate 1b having an opening 1f provided on the one surface 1aa side, and a thin film portion 1a supported by the base substrate 1b on the other surface 1ab side of the base substrate 1b. . Moreover, the infrared sensor 1 is provided with the infrared detection part 1e which has the infrared absorption parts 1c and 1d which are provided at least in the thin film part 1a and absorb infrared rays.

  Infrared sensor 1 is arranged in thin film part 1a which faces opening 1f so that at least a part of infrared absorption parts 1c and 1d can absorb infrared rays from lens 3 in the thickness direction. In the infrared sensor 1, the other surface 1ab side of the base substrate 1b is the package base 2 side.

  In the infrared detecting device 10 of the present embodiment, the thickness direction of the opening 1 f of the infrared sensor 1 is used for securing the focal length of the lens 3. In other words, the infrared detection device 10 is compared with the infrared detection device in which the one surface 1aa side of the base substrate 1b is set to the package base 2 side by increasing the focal length of the lens 3 using the opening 1f of the infrared sensor 1. Thus, the lens 3 and the infrared sensor 1 can be arranged closer to each other.

  The infrared detection device 10 can have high sensitivity by including the lens 3 that collects infrared rays on the infrared sensor 1. In addition, the infrared detection device 10 is configured such that the other surface 1ab side of the base substrate 1b on the base substrate 1b is the package base 2 side, so that the distance between the lens 3 and the infrared sensor 1 is closer, and the entire infrared detection device 10 is By reducing the height, the size can be reduced. That is, the infrared detection device 10 of the present embodiment can be further downsized.

  Hereinafter, each configuration of the infrared detection device 10 of the present embodiment will be described in more detail.

  The infrared sensor 1 uses a pyroelectric infrared sensor 1 using a pyroelectric effect that generates a charge due to a temperature change. The infrared sensor 1 includes, for example, a base substrate 1b using a silicon substrate, and a thin film portion formed of a laminated film of a silicon oxide film (not shown) and a silicon nitride film (not shown) on the base substrate 1b. 1a. The infrared sensor 1 is provided with a space by an opening 1f that opens on the one surface 1aa side of the base substrate 1b. The infrared sensor 1 has a diaphragm structure having a thin film portion 1a supported by the base substrate 1b on the other surface 1ab side of the base substrate 1b.

The infrared sensor 1 includes an infrared absorbing portion 1c made of a pyroelectric thin film on the lens 3 side of the thin film portion 1a. In addition, the infrared sensor 1 is provided with a first electrode 8a that is electrically connected to the infrared absorbing portion 1c on the lens 3 side of the infrared absorbing portion 1c. The infrared sensor 1 includes an infrared absorbing portion 1d made of a pyroelectric thin film on the package base 2 side of the thin film portion 1a. The infrared sensor 1 includes a second electrode 8b that is electrically connected to the infrared absorbing portion 1d on the package base 2 side of the infrared absorbing portion 1d. In addition, the infrared sensor 1 can use the composite metal salt which shows the pyroelectric effect characteristic as the infrared absorption parts 1c and 1d. Examples of the composite metal salt include PTO (PbTiO ₃ ), PbNbO ₃ , PLZT ((Pb, La) (Zr, Tr) O ₃ )) and PZT (Pb (Zr, Ti) O ₃ ).

  The infrared sensor 1 is a position where the infrared absorbing portion 1c on the lens 3 side in the thin film portion 1a and the infrared absorbing portion 1d on the package base 2 side in the thin film portion 1a overlap in a plan view so that the infrared light from the lens 3 can be absorbed. Is arranged. In other words, the infrared sensor 1 is arranged at a position overlapping in plan view on both sides of the thin film portion 1a facing the opening 1f so that at least a part of the infrared absorbing portions 1c and 1d can absorb infrared rays from the lens 3. Yes. The infrared sensor 1 is configured to detect infrared rays using a thin film portion 1a, infrared absorption portions 1c and 1d arranged at positions overlapping on both sides in the thickness direction of the thin film portion 1a, a first electrode 8a, and a second electrode 8b. Part 1e is configured. The infrared sensor 1 is provided with a connection wiring 8aa on the one surface 1aa side of the thin film portion 1a which is the lens 3 side of the thin film portion 1a. In addition, the infrared sensor 1 is provided with a first terminal portion 8ac on the other surface 1ab side of the thin film portion 1a on the package base 2 side of the thin film portion 1a.

  In the infrared sensor 1, the connection wiring 8aa electrically connected to the first electrode 8a is electrically connected to the first terminal portion 8ac through the through-hole wiring 8ab penetrating the thin film portion 1a. . In the infrared sensor 1, the connection wiring 8ba electrically connected to the second electrode 8b is electrically connected to the second terminal portion 8bc. The infrared sensor 1 is mounted via a bump 7 on a semiconductor element 6 (described later) mounted on the surface 2aa of the package base 2. The infrared sensor 1 absorbs infrared rays collected by the lens 3 with a pair of infrared absorbing portions 1c and 1d provided through a thin film portion 1a. In the infrared sensor 1, charges are generated by the absorbed infrared rays based on the temperature change of the infrared absorbing portions 1 c and 1 d disposed opposite to each other through the thin film portion 1 a made of an insulator. The infrared sensor 1 can output the charges of the infrared absorbing portions 1c and 1d from the first terminal portion 8ac and the second terminal portion 8bc to the semiconductor element 6 for signal processing via the bumps 7 and 7 separately.

  Such an infrared sensor 1 is not shown, but can be formed by the following method, for example.

  In the infrared sensor 1, for example, an insulating film made of a silicon oxide film is formed on each of one surface side and the other surface side of an SOI substrate serving as the base substrate 1b by a thermal oxidation method or the like. Thereby, the base substrate 1b can include an insulating film on the one surface 1aa side and the other surface 1ab side. Note that the SOI substrate to be the base substrate 1b has a structure in which a buried oxide film made of a silicon oxide film is sandwiched between a single crystal silicon substrate and a single crystal silicon layer. After that, the SOI substrate forms an infrared absorption film to be an infrared absorption portion 1d made of a pyroelectric material (for example, PZT) on the entire surface of the other surface side of the SOI substrate that is the other surface 1ab side of the base substrate 1b. The infrared absorption film can be formed by, for example, a sputtering method, a CVD method, a sol-gel method, or a transfer method.

  Next, the infrared sensor 1 can form the infrared absorbing portion 1d by patterning the infrared absorbing film into a predetermined shape using a lithography technique and an etching technique. For example, the infrared absorbing portion 1d can be formed in a rectangular shape in a plan view, but is not limited to a rectangular shape, and may have various shapes such as a circular shape. Subsequently, a second metal film (for example, a NiCr film) serving as a basis for the second electrode 8b, the connection wiring 8ba, and the second terminal portion 8bc is formed on the entire surface on the other surface side of the SOI substrate. The second metal film can be formed by, for example, a sputtering method or a CVD method. The second metal film is not limited to the NiCr film, and may be, for example, an Al film or an Al—Si film, or Ti as an adhesion film for improving the adhesion interposed between the Au film and the Au film and the insulating film. You may comprise with the film | membrane. The material of the adhesion film is not limited to Ti, and for example, Cr, Nb, Zr, TiN, TaN, or the like may be used.

In the infrared sensor 1, the infrared absorbing portion 1d is directly formed on the insulating film on the other surface 1ab side of the base substrate 1b. However, between the insulating film on the other surface 1ab side of the base substrate 1b and the infrared absorbing portion 1d. In addition, a seed layer (not shown) may be interposed as a base when forming the infrared absorbing portion 1d. The infrared sensor 1 can improve the crystallinity of the infrared absorbing portion 1d by forming a seed layer. Examples of the material for the seed layer include PLT ((Pb, La) TiO ₃ ), PTO, SRO (SrRuO ₃ ), and the like, which are a kind of conductive oxide material.

  Next, on the SOI substrate on which the infrared sensor 1 is formed, the second metal film is patterned into a predetermined shape using a lithography technique and an etching technique. Thereby, the infrared sensor 1 can be provided with the 2nd electrode 8b which consists of a part of 2nd metal film, connection wiring 8ba, 1st terminal part 8ac, and 2nd terminal part 8bc. In the infrared sensor 1, the connection wiring 8ba, the first terminal portion 8ac, and the second terminal portion 8bc are formed simultaneously with the second electrode 8b. The second electrode 8b, the connection wiring 8ba, the first terminal portion 8ac, and the second terminal portion 8bc are not only formed at the same time by patterning the second metal film, but also the connection wiring 8ba, The first terminal portion 8ac and the second terminal portion 8bc may be formed separately. In the etching of the second metal film, for example, an RIE method or an ion milling method can be appropriately employed.

  Subsequently, the SOI substrate is formed with an opening 1f in which one surface 1aa of the base substrate 1b is opened by using an etching technique such as a lithography technique and a Deep-RIE method. Further, in the SOI substrate, a through hole for the through hole wiring 8ab is formed in the thin film portion 1a by etching by the RIE method.

  Next, the SOI substrate has an infrared absorption portion that becomes an infrared absorption portion 1c made of a pyroelectric material (for example, PZT) on one surface side of the SOI substrate that is the entire surface of the thin film portion 1a in the opening 1f of the base substrate 1b. The film is formed in the same manner as the other surface 1ab side of the base substrate 1b. Subsequently, the infrared sensor 1 forms the infrared absorbing portion 1c by patterning the infrared absorbing film into a predetermined shape using a lithography technique and an etching technique. The infrared absorbing portion 1c is formed in a rectangular shape through the thin film portion 1a so as to overlap the infrared absorbing portion 1d in plan view. The shape of the infrared absorbing portion 1c is not limited to a rectangular shape, and may be various shapes such as a circular shape. In addition, the SOI substrate has the first electrode 8a, the connection wiring 8aa, and the through-hole wiring 8ab on the entire surface on the lens 3 side in the thin film portion 1a in the same manner as the other surface 1ab side of the base substrate 1b. It is formed by forming a NiCr film by the CVD method or the like.

  The infrared sensor 1 can form a plurality of infrared sensors 1 with high productivity by forming each component at the wafer level and then performing dicing to be divided into individual infrared sensors 1.

  The package base 2 can be formed of various materials, and may be a metal material or a semiconductor material. As the package base 2, for example, a ceramic substrate provided with a circuit pattern to be electrically connected to the infrared sensor 1 on the surface 2 aa side of the package base 2 can be used. The package base 2 can be provided with the infrared sensor 1, and in addition to the infrared sensor 1, a signal processing semiconductor element 6 that amplifies a detection signal from the infrared sensor 1 may be mounted. The package substrate 2 can be used in various shapes, and may be plate-shaped or bottomed cylindrical.

  The lens 3 is capable of condensing infrared rays from the outside of the infrared detection device 10 onto the infrared sensor 1. The lens 3 can have various shapes depending on the size and position of the infrared sensor 1. The lens 3 may be, for example, a biconvex lens shape or a plano-convex lens shape. Moreover, the lens 3 can also be made into a Fresnel lens shape. The material of the lens 3 may be formed of, for example, a polyethylene resin material that can transmit infrared rays, or may be formed of a semiconductor material such as silicon, germanium, or zinc sulfide.

  The cover 4 is provided with a lens 3 that covers the infrared sensor 1 and causes the infrared sensor 1 to focus infrared rays on the infrared sensor 1. The cover 4 can be formed by, for example, a metal package provided with a through hole for holding the lens 3. The cover 4 is not limited to a metal package, and can be formed of a ceramic material, a semiconductor material, a resin material, or the like. Further, the infrared detecting device 10 does not necessarily need to form the cover 4 and the lens 3 separately, and the cover 4 and the lens 3 may be integrally formed.

  In addition, the infrared detecting device 10 of the present embodiment reflects the infrared rays from the lens 3 side that is not absorbed by the infrared absorbing portions 1c and 1d and passes through the infrared absorbing portions 1c and 1d to the infrared absorbing portions 1c and 1d. A film 5 is provided on the package substrate 2 side. As shown in FIG. 2, in the infrared detecting device 10, the infrared absorbing portion 1 c disposed on the lens 3 side in the thin film portion 1 a of the infrared sensor 1 absorbs the infrared ray IR <b> 1 from the lens 3 side. The infrared detecting device 10 absorbs the infrared ray IR2 transmitted without being absorbed by the infrared ray absorbing portion 1c disposed on the lens 3 side in the thin film portion 1a of the infrared sensor 1 by the infrared ray absorbing portion 1d on the package base 2 side in the thin film portion 1a. Can be made.

  Furthermore, in the infrared detecting device 10 of the present embodiment, the infrared reflecting film 5 is provided on the package base 2 side, so that the infrared IR3 transmitted through the infrared absorbing portions 1c and 1d is returned to the infrared absorbing portions 1c and 1d again. Can be reflected. The infrared detecting device 10 can further increase the sensitivity by causing the infrared absorbing portions 1c and 1d to absorb the infrared rays reflected by the infrared reflecting film 5.

  In particular, in the infrared detection device 10 of the present embodiment, since the infrared sensor 1 is arranged with the other surface 1ab side of the base substrate 1b as the package base 2 side, the infrared absorbing portions 1c and 1d and the infrared reflection film 5 are arranged. The gap can be narrow. The infrared detecting device 10 can further increase sensitivity by setting the distance between the infrared absorbing portions 1c and 1d and the infrared reflecting film 5 to a resonance structure that is ¼ of the wavelength of infrared rays to be detected. It becomes possible.

  The semiconductor element 6 performs an amplification process on the detection signal from the infrared sensor 1 in cooperation with the infrared sensor 1. The semiconductor element 6 can be constituted by, for example, a signal processing IC chip. The infrared detection device 10 can amplify the detection signal from the infrared sensor 1 by an amplifier circuit (AMP) of the semiconductor element 6 and output the amplified signal to the outside. In the infrared detection device 10 of the present embodiment, the infrared sensor 1 and the semiconductor element 6 are formed separately, but the infrared sensor 1 and the semiconductor element 6 may be formed integrally. The infrared detecting device 10 is bonded to the package base 2 which is a stem of the semiconductor element 6 by an adhesive (not shown). In the infrared detecting device 10, the infrared sensor 1 is mounted on the semiconductor element 6 using bumps 7 made of solder. The infrared detection device 10 joins the bump 7 made of solder formed in advance on the connection terminal portions 6 a and 6 b of the semiconductor element 6 and the infrared sensor 1.

  The infrared detecting device 10 is electrically connected by bonding the first terminal portion 8ac and the second terminal portion 8bc of the infrared sensor 1 to bumps 7 and 7 formed on the connection terminal portions 6a and 6b of the semiconductor element 6. doing. The infrared detection device 10 includes external connection terminals 2 a and 2 b outside the package base 2. The infrared detection device 10 is configured to output the semiconductor element 6 and the external connection terminals 2a and 2b through a through wiring (not shown) penetrating the package base 2 so that the detection signal detected by the infrared sensor 1 can be output. Are electrically connected. The infrared detecting device 10 can output a detection signal from the infrared sensor 1 to the outside from the external connection terminals 2a and 2b.

  In the infrared detection device 10 of the present embodiment, the package base 2 is sealed with a cover 4. The infrared detecting device 10 can adhere and harden the cover 4 on the edge of the package base 2 using a sealing adhesive layer (not shown) made of glass. The infrared detecting device 10 can also use AuSi, solder, organic epoxy resin, or the like instead of glass as a sealing adhesive layer used for sealing.

The infrared detecting device 10 is substantially sealed even if it is exposed to the vacuum sensor or each infrared sensor 1 so that the inside of the infrared detecting device 10 is not contaminated by the cover 4 including the lens 3 and the package base 2. No gas or the like is hermetically sealed in a pressurized state. In the infrared detection device 10, examples of a gas that does not substantially affect the infrared sensor 1 include an inert gas such as Ar gas and nitrogen gas (N ₂ ). The infrared detection device 10 may raise the pressure inside the infrared detection device 10 (higher than atmospheric pressure) by hermetically sealing the package base 2 and the cover 4 in a pressurized state. The infrared detection device 10 can suppress the gas from flowing into the air-tightly sealed infrared detection device 10 by raising the pressure inside the infrared detection device 10. Thereby, the infrared detection apparatus 10 can be made more reliable.

(Embodiment 2)
The infrared detection device 10 of the present embodiment shown in FIG. 3 uses an infrared sensor 1 that uses the thermoelectromotive force effect instead of using the infrared sensor 1 that uses the pyroelectric effect of the first embodiment shown in FIG. Are mainly different. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  As shown in FIG. 3, the infrared detection device 10 of this embodiment includes an infrared sensor 1 that detects infrared rays and a package base 2 on which the infrared sensor 1 is disposed. The infrared detection device 10 includes a cover 4 that includes a lens 3 that covers the infrared sensor 1 and focuses infrared light (see the broken arrow in FIG. 3) on the infrared sensor 1.

  As shown in FIGS. 3 to 5, the infrared sensor 1 of the infrared detecting device 10 is supported on the base substrate 1b on the other surface 1ab side of the base substrate 1b and the base substrate 1b in which the opening 1f is provided on the one surface 1aa side. And a thin film portion 1a. Moreover, the infrared sensor 1 is provided with the infrared detection part 1h which has the infrared absorption parts 1j and 1k which are provided at least in the thin film part 1a and absorb infrared rays.

  The infrared sensor 1 is arranged at a position overlapping in plan view on both sides of the thin film portion 1a facing the opening 1f so that at least a part of the infrared absorbing portions 1j and 1k can absorb infrared rays from the lens 3 in the thickness direction. ing. In the infrared sensor 1, the other surface 1ab side of the base substrate 1b is the package base 2 side.

  The infrared detection device 10 of the present embodiment can be further reduced in size, similarly to the infrared detection device 10 of the first embodiment.

  More specifically, the infrared sensor 1 has, for example, a diaphragm structure in which the thin film portion 1a is supported by the base substrate 1b using a silicon substrate by the thin film portion 1a itself. The infrared sensor 1 includes a silicon oxide film 1a1 formed on the other surface 1ab side of a base substrate 1b using a silicon substrate. The infrared sensor 1 includes a silicon nitride film 1a2 on the opposite side of the silicon oxide film 1a1 from the base substrate 1b. In the infrared sensor 1, a silicon oxide film 1a1 and a silicon nitride film 1a2 constitute a thin film portion 1a. The infrared sensor 1 includes a thermocouple 9 in the silicon nitride film 1a2 of the thin film portion 1a.

  The infrared sensor 1 includes a thermocouple 9 that is provided across the thin film portion 1a on the base substrate 1b side and the thin film portion 1a on the opening 1f side in plan view and detects a temperature change due to absorption of infrared light. (See FIG. 4). The infrared detecting device 10 of the present embodiment forms a thermopile by electrically connecting a plurality of thermocouples 9 in series. In the infrared detecting device 10 of the present embodiment, an infrared detecting unit 1h is configured by a thermocouple 9, an infrared absorbing unit 1k that covers the thermocouple 9, and an infrared absorbing unit 1j provided on the lens 3 side of the thin film unit 1a. (See FIGS. 3 and 5).

  The infrared sensor 1 is not limited to a diaphragm structure. Although not shown, the infrared sensor 1 may have a heat insulating bridge structure that supports the thin film pedestal portion on the opening 1f side by a support portion that thermally insulates from the base substrate 1b side. In this case, the infrared sensor 1 may be provided with the thermocouple 9 from the base substrate 1b side to the thin film pedestal part via the support part. Moreover, the infrared sensor 1 is good also as a structure provided with the some infrared detection part 1h not only the structure provided with the one infrared detection part 1h in the thin film part 1a. The infrared sensor 1 can function as an infrared image sensor by arranging a plurality of infrared detection units 1h in a matrix in a plan view.

  The infrared sensor 1 includes a pair of thermocouple wires 9 a and 9 b made of different materials as the thermocouple 9. In the infrared sensor 1, a pair of thermocouple wires 9a and 9b may be arranged side by side on the package base 2 side of the thin film portion 1a, or an insulating film (not shown) is provided in the thickness direction of the thin film portion 1a. It may be arranged via. In the infrared detecting device 10 of the present embodiment, an infrared absorbing portion 1j is provided on the lens 3 side of the thin film portion 1a in the opening 1f of the infrared sensor 1. Thereby, the infrared detecting device 10 can efficiently absorb the infrared light collected by the lens 3 by the infrared absorbing unit 1j. Therefore, the infrared sensor 1 can detect infrared rays with high sensitivity even if the infrared detection unit 1h is configured on the other surface 1ab side via the thin film portion 1a.

  The infrared sensor 1 is configured such that a thermocouple element 9a and a thermocouple element 9b arranged side by side in a thin film part 1a are covered with an infrared absorbing part 1k made of an insulating material. In the infrared sensor 1, for example, a thermocouple 9 is formed on the package base 2 side in a thin film portion 1a made of a laminated film of a silicon oxide film 1a1 and a silicon nitride film 1a2. In the infrared sensor 1, an insulating material such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film can be suitably used as a material constituting the infrared absorbing portion 1k.

  Although not shown, the infrared sensor 1 may be formed by forming a metal film such as TiN on an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film that constitutes the infrared absorbing portion 1k. . For example, the infrared detecting device 10 can set the distance between the metal film and the infrared reflecting film 5 to ¼ of the wavelength of infrared rays detected by the infrared sensor 1. In addition, the infrared detecting device 10 can use, for example, a TiN film having a sheet resistance of 377 Ω / □ as the metal film. Thereby, the infrared detecting device 10 has an optical resonance structure of the metal film and the infrared reflecting film 5 and can achieve higher sensitivity.

  More specifically, as shown in FIG. 6, the infrared detecting device 10 includes an infrared absorbing portion 1k on the other surface 1ab side of the insulating film 1a4 in addition to the insulating film 1a4 of the insulating material constituting the infrared absorbing portion 1k. A metal film 11 is provided. In other words, the metal film 11 functions as a component constituting the infrared absorbing portion 1k. Further, the infrared detection device 10 includes the infrared reflection film 5 on the semiconductor element 6 so as to face the metal film 11. Thereby, in the infrared detecting device 10, the infrared IR4 is reflected by the infrared reflecting film 5, and the infrared IR5 is directed to the metal film 11 side. In the infrared detecting device 10, the infrared IR 5 is reflected by the metal film 11, and the infrared IR 6 is directed toward the infrared reflecting film 5.

  Infrared detector 10 uses, for example, TiN film or Ti film having a sheet resistance of 377 Ω / □ as metal film 11. In addition, the infrared detecting device 10 uses, for example, a film of a metal (for example, gold or aluminum) having a sheet resistance smaller than 10Ω / □ as the infrared reflecting film 5. Thereby, the infrared detecting device 10 has an optical resonance structure of the metal film 11 and the infrared reflecting film 5, and can absorb near 100% of the infrared light having a center wavelength of 11.5 μm theoretically on the metal film 11 side. . Therefore, for example, the infrared detection device 10 can efficiently absorb infrared IR4 having a wavelength of 10 to 13 μm on the metal film 11 side, thereby achieving higher sensitivity.

  In the infrared sensor 1, the pair of thermocouple wires 9a and 9b of the thermocouple 9 are connected to each other made of a metal material (for example, Al—Si) at the center of the thin film portion 1a through the contact hole 1a3 in a plan view. It is electrically connected by the part 12 to form the hot junction T1. In the infrared sensor 1, the thermocouple 9 is electrically connected to the cold junction T2 by a connection portion 13 made of a metal material (for example, Al-Si) on the base substrate 1b side of the thin film portion 1a in plan view. Forming. In the infrared sensor 1, the connecting portion 12 is electrically insulated and separated by an interlayer insulating film functioning as the infrared absorbing portion 1k on the other surface 1ab side of the base substrate 1b. Thereby, the infrared sensor 1 is configured by electrically connecting ten thermocouples 9 in series.

The infrared sensor 1 includes a first terminal portion 8ac serving as an output terminal to the outside connected to the thermocouple element 9a. Similarly, the infrared sensor 1 includes a second terminal portion 8bc serving as an output terminal to the outside connected to the thermocouple element 9b. One of the thermocouples 9 is a first thermocouple element 9a formed of p-type polycrystalline silicon, and the other is a second thermocouple element 9b formed of n-type polycrystalline silicon. In the thermocouple 9, the material of the first thermocouple element 9a may be n-type polycrystalline silicon, and the material of the second thermocouple element 9b may be p-type polycrystalline silicon. The material of the first and second thermocouple wires 9a and 9b is not limited to polycrystalline silicon, but is polycrystalline silicon germanium, porous silicon, bismuth telluride (Bi ₂ Te ₃ ), antimony telluride. (Sb ₂ Te ₃ ) may also be used. One of the materials of the first and second thermocouple wires 9a and 9b may be a semiconductor material and the other may be Al or Au which is a metal material.

  In the infrared sensor 1, an insulating film is formed so as to cover the thermocouple 9 provided in the silicon nitride film 1a2 on the package base 2 side in the thin film portion 1a. The infrared sensor 1 uses BPSG (Boron Phosphor Silicate Glass) as an insulating material that covers the thermocouple 9. The thin film portion 1 a forms an interlayer insulating film with a BPSG film covering the thermocouple 9. In the thin film portion 1a, a passivation film is formed on the interlayer insulating film. The passivation film is composed of a laminated film of a PSG (Phosphor Silicate Glass) film and an NSG (Nondoped Silicate Glass) film formed on the PSG film, but is not limited to this, and is composed of, for example, a silicon nitride film. May be. In the infrared sensor 1, an infrared absorbing portion 1 k is configured by an interlayer insulating film that covers the thermocouple 9 and a passivation film. Infrared sensor 1 can make infrared detection part 1h absorb infrared light efficiently by adjusting the refractive index and film thickness of the interlayer insulation film and passivation film which constitute infrared absorption part 1k.

  The infrared detecting device 10 includes a semiconductor element 6 for signal processing that is formed separately from the infrared sensor 1 and cooperates with the infrared sensor 1. In the infrared detecting device 10, the semiconductor element 6 is bonded to a wiring pattern (not shown) formed in advance on the package base 2 using an adhesive 14 that is a conductive paste. In the infrared detecting device 10, the infrared sensor 1 is mounted on the semiconductor element 6 using bumps 7 made of solder. The infrared sensor 1 electrically connects the first terminal portion 8ac and the second terminal portion 8bc of the infrared sensor 1 to the connection terminal portions 6a and 6b of the semiconductor element 6 by a plurality of bumps 7.

  In the infrared detection device 10, the semiconductor element 6 on which the infrared sensor 1 is mounted and the wiring pattern of the package substrate 2 are wire-bonded with wires 15. The infrared detection device 10 can electrically connect the outside of the infrared detection device 10 and the infrared sensor 1 via a wire 15 or the like. In the infrared detection device 10, for example, a gold wire or an aluminum wire can be used as the wire 15.

  Note that the infrared detection device 10 does not necessarily include the semiconductor element 6. In the infrared detecting device 10, the infrared reflective film 5 may be provided on the package base 2, or the infrared reflective film 5 may not be provided. Therefore, for example, as shown in FIG. 7, the infrared detection device 10 may mount the infrared sensor 1 on the terminal portion 6 c of the wiring pattern provided on the package substrate 2 using the bumps 7. In the infrared detecting device 10, the wiring pattern and the external connection terminals 2 a and 2 b are electrically connected through a through wiring (not shown) penetrating the package base 2.

  In the infrared detecting device 10 of the present embodiment, the infrared sensor 1 using infrared electromotive force is exemplified as the infrared sensor 1, but in addition to this, a bolometer type infrared sensor or a quantum infrared using infrared photoelectromotive force. A sensor or the like may be used.

(Embodiment 3)
The infrared detection device 10 of the present embodiment shown in FIG. 8 is like the infrared detection device 10 shown in FIG. 3, instead of hermetically sealing the infrared sensor 1 with the package base 2 and the cover 4 provided with the lens 3. The main difference is that a part of the infrared sensor 1 is hermetically sealed. In addition, about the component similar to Embodiment 1 and Embodiment 2, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  As shown in FIG. 8, the infrared detection device 10 of the present embodiment hermetically seals, for example, the infrared sensor 1 and the cover portion 4 formed integrally with the lens 3. In the infrared detecting device 10, for example, a metal pattern layer 1g is formed on the one surface 1aa side of the base substrate 1b having a rectangular frame shape by the opening 1f. In the infrared detecting device 10, a frame-shaped metal pattern layer 4 a is formed in a portion corresponding to the metal pattern layer 1 g in the cover 4. In the infrared detecting device 10, for example, the metal pattern layer 1 g formed on the one surface 1 aa side of the base substrate 1 b and the metal pattern layer 4 a of the cover 4 are bonded by room temperature bonding of Au—Au. Similarly, the infrared detecting device 10 hermetically seals the infrared sensor 1 and the semiconductor element 6. The infrared detecting device 10 hermetically seals the thin film portion 1 a side of the infrared sensor 1 and the semiconductor element 6 via solder 16. The infrared detecting device 10 has a metal pattern portion 8cc formed in a frame shape along the outer peripheral portion on the other surface 1ab side of the base substrate 1b using a silicon substrate. In the infrared detecting device 10, a frame-shaped metal pattern portion 6 d is formed at a portion corresponding to the metal pattern portion 8 cc of the semiconductor element 6. In the infrared detecting device 10, a metal pattern portion 8 bc formed on the other surface 1 ab side of the base substrate 1 b and a metal pattern portion 6 d formed at a corresponding portion of the semiconductor element 6 are joined by bumps 7. The infrared detecting device 10 may be hermetically sealed by bonding the infrared sensor 1 and the semiconductor element 6 by, for example, Au-Au room temperature bonding.

  In addition, the infrared detecting device 10 has the cover 4 formed of a silicon material. The infrared detecting device 10 uses a silicon substrate anodizing technique to form a convex portion 3 a constituting the lens 3 on the cover portion 4 so as to protrude outside the infrared detecting device 10. More specifically, in order to form a semiconductor lens to be the lens 3 by applying an anodic oxidation technique, an anode whose pattern is designed according to a desired lens shape is provided on one surface side of a semiconductor substrate (for example, a silicon substrate). It is formed so as to make ohmic contact with the semiconductor substrate. For example, in order to form the convex portion 3 a of the lens 3, the semiconductor substrate is provided with a portion having a circular opening in the conductive layer after forming a conductive layer serving as the basis of the anode on one surface of the semiconductor substrate. Patterning is performed so that a part of one surface of the semiconductor substrate is exposed in a circular shape. Next, the entire region where the porous portion is to be formed on the other surface of the semiconductor substrate is immersed in an electrolytic solution capable of etching away oxides of constituent elements of the semiconductor substrate. Thereafter, a current is passed between the cathode and the anode arranged opposite to the other surface side of the semiconductor substrate to form a porous portion having a desired shape on the other surface side of the semiconductor substrate by oxidation. Subsequently, the convex portion 3a of the lens 3 can be formed by removing the porous portion formed on the semiconductor substrate by etching or the like. Similarly, the infrared detecting device 10 uses the anodic oxidation technology of a silicon substrate to form a convex portion 3b constituting the lens 3 on the cover 4 so as to protrude into the infrared detecting device 10.

  The infrared detecting device 10 is substantially sealed even if it is vacuum-sealed or exposed to each infrared sensor 1 or the like so as not to contaminate the inside of the airtightly sealed interior of the semiconductor element 6, the infrared sensor 1, and the cover 4. A gas having no influence may be sealed in a pressurized state. As a result, the infrared detecting device 10 is less likely to escape heat from the infrared detecting unit 1h whose temperature has risen, and the sensitivity can be further increased. In addition, the infrared detection device 10 of the present embodiment covers the side surfaces of the infrared sensor 1 and the cover 4 provided with the lens 3 with resin on the semiconductor element 6 by molding or the like. The mechanical strength of is increased.

  The cover 4 provided with the lens 3 and the infrared sensor 1 may have a chip size package structure using a wafer level package technique in which the cover 4 is separated after being bonded at the wafer level. Thereby, the cover part 4 provided with the lens 3 and the infrared sensor 1 can improve alignment accuracy.

(Embodiment 4)
The infrared detection device 10 of the present embodiment shown in FIG. 9 uses the semiconductor element 6 itself as an infrared ray instead of placing the infrared sensor 1 on the semiconductor element 6 separate from the package base 2 of the infrared detection device 10 shown in FIG. It differs mainly in the point utilized for arrangement | positioning of the sensor 1. FIG. In addition, about the component similar to Embodiment 3, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  As shown in FIG. 9, the infrared detection device 10 of this embodiment includes a semiconductor element 6 for signal processing that cooperates with the infrared sensor 1 formed separately from the infrared sensor 1. The infrared detecting device 10 hermetically seals the thin film portion 1 a side of the infrared sensor 1 and the semiconductor element 6 via solder 16. The infrared detecting device 10 has a metal pattern portion 8cc formed in a frame shape along the outer peripheral portion on the other surface 1ab side of the base substrate 1b using a silicon substrate. In the infrared detecting device 10, a frame-shaped metal pattern portion 6 d is formed at a portion corresponding to the metal pattern portion 8 cc of the semiconductor element 6. In the infrared detecting device 10, a metal pattern portion 8 bc formed on the other surface 1 ab side of the base substrate 1 b and a metal pattern portion 6 d formed at a corresponding portion of the semiconductor element 6 are joined by bumps 7.

  In the infrared detecting device 10, the infrared reflecting film 5 that reflects the infrared rays from the lens 3 is provided on the semiconductor element 6 on the infrared absorbing portions 1 j and 1 k of the infrared sensor 1. The infrared detecting device 10 electrically connects the infrared sensor 1 and the semiconductor element 6 and the infrared sensor 1 and the semiconductor element 6 through the through-hole wiring 6 ca that is electrically connected to the metal pattern portion 6 d of the semiconductor element 6. And a ground terminal 2c made of a solder ball to be grounded. The infrared detection device 10 may be configured to be electrically connected to the external connection terminals 2a and 2b made of solder balls so as to output a detection signal from the infrared sensor 1 to the outside through a through wiring (not shown). Good.

  The infrared detecting device 10 hermetically seals the semiconductor element 6 and the infrared sensor 1 with the semiconductor element 6 itself as the package base 2. In addition, the infrared detecting device 10 hermetically seals the infrared sensor 1 and the cover 4 integrally formed with the lens 3. The infrared detection device 10 increases the mechanical strength of the infrared detection device 10 by covering the side surfaces of the infrared sensor 1 and the cover 4 including the lens 3 with resin on the semiconductor element 6 by molding or the like. ing.

  In the infrared detecting device 10 of this embodiment, the semiconductor element 6 itself is used as the package base 2 for the arrangement of the infrared sensor 1. In other words, the infrared detection device 10 of the present embodiment has a chip size package structure. Thereby, the infrared detecting device 10 mainly has the thickness of the covering portion 4 provided with the lens 3, the infrared sensor 1, and the package base 2 on which the infrared sensor 1 is mounted. The thickness can be reduced. That is, the infrared detection device 10 of the present embodiment can be further downsized.

(Embodiment 5)
The infrared detection device 10 of the present embodiment shown in FIG. 10 is mainly different in the structure of the infrared sensor 1 and the infrared detection unit 1n in the first embodiment shown in FIG. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  As shown in FIG. 10, the infrared detection device 10 of this embodiment includes an infrared sensor 1 that detects infrared rays, and a package base 2 on which the infrared sensor 1 is disposed. The infrared detection device 10 includes a cover 4 that includes a lens 3 that covers the infrared sensor 1 and focuses infrared light (see the broken arrow in FIG. 10) on the infrared sensor 1.

  The infrared sensor 1 of the infrared detecting device 10 includes a base substrate 1b having an opening 1f provided on the one surface 1aa side, and a thin film portion 1a supported by the base substrate 1b on the other surface 1ab side of the base substrate 1b. . Moreover, the infrared sensor 1 is provided with the infrared detection part 1n which has the infrared absorption parts 1m and 1r which are provided at least in the thin film part 1a and absorb infrared rays.

  The infrared sensor 1 is arranged at a position overlapping in plan view on both sides of the thin film portion 1a facing the opening 1f so that at least a part of the infrared absorbing portions 1m and 1r can absorb infrared rays from the lens 3 in the thickness direction. ing. In the infrared sensor 1, the other surface 1ab side of the base substrate 1b is the package base 2 side.

  Here, the infrared detection unit 1n in the infrared detection device 10 of the present embodiment includes a first electrode portion 8d provided on the other surface 1ab side of the thin film portion 1a. The infrared detection unit 1n includes a pyroelectric layer 21 provided on the opposite side of the first electrode unit 8d from the thin film unit 1a side. The infrared detecting unit 1n includes a second electrode portion 8e provided on the opposite side of the pyroelectric layer 21 from the first electrode portion 8d side. Infrared detector 1n in infrared detector 10 of this embodiment functions as infrared absorber 1r in which pyroelectric layer 21 is provided on the other surface 1ab side of thin film portion 1a.

  The infrared detection device 10 of the present embodiment includes an infrared detection unit 1n configured such that the infrared sensor 1 sandwiches the pyroelectric layer 21 between the first electrode unit 8d and the second electrode unit 8e. In addition, the infrared sensor 1 is provided with an infrared absorbing portion 1m whose temperature rises by the incidence of infrared rays on the entire surface of the thin film portion 1a facing the opening 1f. In other words, the infrared sensor 1 has a structure in which a pyroelectric current is generated in the infrared detection unit 1n due to a temperature rise caused by the pyroelectric layer 21 that also functions as the infrared absorption unit 1m and the infrared absorption unit 1r absorbing infrared rays.

  Thereby, the infrared detection device 10 of the present embodiment can further increase the sensor sensitivity with a relatively simple configuration.

  The infrared absorbing portion 1m may be provided as long as it is provided on the one surface 1aa side in the thin film portion 1a and can contribute to the temperature increase on the infrared detecting portion 1n side by absorbing infrared rays. Infrared sensor 1 can form infrared absorption part 1m with a gold black film etc., for example. Thereby, the infrared sensor 1 can have a structure in which the infrared absorbing portion 1m itself causes a temperature rise. When gold black is used as the material of the infrared absorbing portion 1m, the infrared absorbing portion 1m can obtain a relatively high infrared absorptivity without depending on the wavelength of infrared rays.

  In addition, the infrared absorbing portion 1m is not limited to gold black as long as it can absorb infrared rays, and carbon black containing resin material or PZT may be used. Furthermore, although not shown, the infrared absorbing portion 1m may be, for example, an infrared resonant metal thin film and a first electrode portion 8d that can function as an infrared reflecting film for an optical resonance structure. Thereby, the infrared absorption part 1m can also absorb infrared rays similarly to the optical resonance structure shown in FIG.

  In the infrared detecting device 10 of the present embodiment, the infrared detecting unit 1n is provided only on the other surface 1ab side in the thin film unit 1a. Thereby, in the infrared detection apparatus 10 of this embodiment, compared with the infrared sensor 1 in the first embodiment, on the one surface 1aa side in the thin film portion 1a, between the end portion of the infrared absorption portion 1m and the inner peripheral wall 1fa. It is possible to reduce the gap. Compared with the infrared detection device 10 of the first embodiment, the infrared detection device 10 of the present embodiment also has an effect that the infrared absorption unit 1m can be enlarged and the sensitivity can be further increased. In the infrared detecting device 10 shown in FIG. 10, the end of the infrared absorbing portion 1m and the inner peripheral wall 1fa are shown in close contact, but the end of the infrared absorbing portion 1m and the inner peripheral wall 1fa are not necessarily connected. There is no need for close contact.

  Hereinafter, the infrared sensor 1 in the infrared detection device 10 of the present embodiment will be described.

  In the infrared sensor 1, for example, an insulating film made of a silicon oxide film is formed on each of one surface side and the other surface side of an SOI substrate serving as the base substrate 1b by a thermal oxidation method or the like. Thereby, the base substrate 1b can include an insulating film on the one surface 1aa side and the other surface 1ab side. Thereafter, the SOI substrate is formed on the entire surface of the other surface side of the SOI substrate that is the other surface 1ab side of the base substrate 1b, for example, a metal film (for example, the first electrode portion 8d, the connection wiring 8aa, and the first terminal portion 8ac). For example, an Au film) is formed. The metal film can be formed by, for example, vapor deposition, sputtering, plating, or the like. The infrared sensor 1 can form the first electrode portion 8d, the connection wiring 8aa, and the first terminal portion 8ac by patterning the metal film into a predetermined shape using a lithography technique and an etching technique. Note that the base substrate 1b is not limited to an SOI substrate, and can be formed using a Si substrate.

  Next, the infrared sensor 1 forms an infrared absorption film that becomes the pyroelectric layer 21 made of a pyroelectric material (for example, PZT). The infrared absorption film can be formed by, for example, a sputtering method, a CVD method, a sol-gel method, or a transfer method. The infrared sensor 1 can form the pyroelectric layer 21 by patterning the infrared absorbing film into a predetermined shape by using a lithography technique and an etching technique.

  Subsequently, the infrared sensor 1 is formed on the connection wiring 8aa electrically connected to the first electrode portion 8d and the first terminal portion 8ac on the silicon oxide film serving as the basis of the insulating layer 1a5. The insulating layer 1a5 can be formed by a CVD method or the like. In addition, the infrared sensor 1 can form the insulating layer 1a5 by patterning the silicon oxide film into a predetermined shape using a lithography technique and an etching technique. In the infrared sensor 1, the insulating layer 1a5 electrically insulates the first electrode portion 8d side and the second electrode portion 8e side.

  Next, the infrared sensor 1 forms a metal film (for example, an Au film) serving as a basis for the second electrode portion 8e, the connection wiring 8ba, and the second terminal portion 8bc. The metal film can be formed by, for example, vapor deposition, sputtering, plating, or the like. The infrared sensor 1 can form the second electrode portion 8e, the connection wiring 8ba, and the second terminal portion 8bc by patterning the metal film into a predetermined shape using a lithography technique and an etching technique.

  Next, the SOI substrate is formed, for example, by using an evaporation method or the like on one surface side of the SOI substrate that is the entire surface of the thin film portion 1a in the opening 1f of the base substrate 1b using a vapor deposition method or the like. To do. Subsequently, the infrared sensor 1 forms an infrared absorbing portion 1m by patterning an infrared absorbing film made of gold black or the like into a predetermined shape using a lithography technique and an etching technique. Thereby, the infrared detection part 1n of the infrared sensor 1 used for the infrared detection apparatus 10 of this embodiment can be formed. In the infrared sensor 1 in the infrared detection device 10 of the present embodiment, the temperature rise of the infrared absorption part 1m on the lens 3 side only needs to be transmitted to the infrared detection part 1n on the package base 2 side.

(Embodiment 6)
The infrared detecting device 10 of the present embodiment shown in FIG. 11 is different in that an infrared reflecting layer 25 is provided on the inner peripheral wall 1fa of the opening 1f of the base substrate 1 of the fifth embodiment shown in FIG. In addition, about the component similar to Embodiment 5, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  The infrared sensor 1 in the infrared detecting device 10 of the present embodiment includes an infrared reflecting layer 25 that reflects infrared rays toward the infrared absorbing portions 1m and 1r on the inner peripheral wall 1fa of the opening 1f of the base substrate 1b.

  In the infrared detecting device 10 according to the present embodiment, by forming the infrared reflecting layer 25 on the inner peripheral wall 1fa of the opening 1f, the infrared rays reflected on the inner peripheral wall 1fa side of the opening 1f are incident on the infrared absorbing portions 1m and 1r. It is possible to increase the sensor sensitivity.

  In the infrared sensor 1 of the infrared detection device 10 of the present embodiment, a metal film (for example, an Au film) having a thickness of several hundreds of nanometers is formed on the inner peripheral wall 1fa of the opening 1f by vapor deposition, sputtering, plating, or the like. By doing so, the infrared reflective layer 25 can be formed.

(Embodiment 7)
The infrared detection device 10 of the present embodiment shown in FIG. 12 is different in that the infrared detection unit 1p in the infrared sensor 1 of the fifth embodiment shown in FIG. 10 is provided with a plurality of infrared detection units 1p. To do. In addition, about the component similar to Embodiment 5, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  The infrared sensor 1 in the infrared detection device 10 of the present embodiment includes a plurality of infrared detection units 1p. The infrared sensor 1 includes a plurality of infrared detection units 1p, thereby enabling vector detection for detecting a motion vector of an object (for example, a person) that emits infrared rays. Moreover, the infrared sensor 1 can also function as an infrared image sensor by arrange | positioning several infrared detection parts 1p in planar view, for example in matrix form. In addition, each infrared detection part 1p is comprised as a common electrode which shared the 1st electrode part 8d. In addition, each infrared detection unit 1p is not shown, but the second electrode unit 8e is an individual electrode formed for each infrared detection unit 1p so that each infrared detection unit 1p can detect and output infrared rays. It is composed. The infrared detection unit 1p may be provided with an electrode for each infrared detection unit 1p as well as when using a common electrode that shares the first electrode unit 8d.

  By the way, when the infrared sensor 1 uses each of the plurality of infrared detection units 1p as one pixel or the like, it is preferable that each of the plurality of infrared detection units 1p can increase the temperature independently by the infrared absorption unit.

  However, in the infrared sensor 1 shown in FIG. 12, since the infrared absorbing portion 1m is provided on the entire surface of the thin film portion 1a on the one surface 1aa side, the temperature of the entire thin film portion 1a tends to increase. Therefore, there is a possibility that it is difficult for the infrared detection device 10 to accurately detect the temperature of each of the plurality of infrared detection units 1p.

  Therefore, in the infrared sensor 1 shown in FIG. 13, in plan view, a plurality of thin film portions 1 a on the one surface 1 aa side corresponding to the infrared absorbing portion 1 r of the infrared detecting portion 1 p on the other surface 1 ab side in the thin film portion 1 a are provided. The infrared absorption part 1q can also be formed. Thereby, in another infrared detecting device 10 of the present embodiment shown in FIG. 13, it is possible to detect the temperature of each of the plurality of infrared detecting units 1p with higher accuracy.

  In addition, in the infrared detection device 10 shown in FIG. 13, in a plan view, the infrared ray is absorbed on the one surface 1aa side of the thin film portion 1a corresponding to the infrared absorption portion 1r of the infrared detection portion 1p on the other surface 1ab side of the thin film portion 1a. It is necessary to form part 1q.

  Therefore, in the infrared detecting device 10 shown in FIG. 13, it is necessary to pattern a film serving as the basis of the infrared absorbing portion in the opening 1f using the lithography technique and the etching technique.

  On the other hand, the infrared sensor 1 of the other infrared detection device 10 of the present embodiment shown in FIG. 14 includes an infrared transmission film 22 that transmits infrared rays on the one surface 1aa side of the thin film portion 1a facing the opening 1f. Yes. The infrared sensor 1 has an optical resonance structure in which light is confined and resonated between the infrared transmission film 22 and the first electrode portion 8d. In the infrared sensor 1, the infrared transmission film 22 functions as a component constituting the infrared absorption portion 1s on the one surface 1aa side in the thin film portion 1a.

  As shown in FIG. 14, the infrared absorption unit 1 s has the first electrode unit 8 d when the infrared sensor 1 has an optical resonance structure in which light is confined and resonated between the infrared transmission film 22 and the first electrode unit 8 d. It is possible to absorb infrared rays at a selected position corresponding to, and raise the temperature. Therefore, as shown in FIG. 13, the infrared sensor 1 is formed with a film that forms the basis of the infrared absorption part on the entire surface of the opening 1f of the thin film part 1a, and a plurality of infrared detection parts 1p are provided for each of the plurality of infrared detection parts 1p. There is no need to form the infrared absorbing portion 1q. Thereby, in the infrared detection device 10 shown in FIG. 14, even if the infrared transmission film 22 constituting the common infrared absorption unit 1s is formed for the plurality of infrared detection units 1n, the infrared detection device 10 of FIG. In comparison, it is possible to detect infrared rays with high accuracy for each infrared detection unit 1p. Further, in the infrared detecting device 10 shown in FIG. 14, even if the infrared transmitting film 22 constituting the common infrared absorbing portion 1s is formed for the plurality of infrared detecting portions 1n, the infrared detecting device 10 is compared with the infrared detecting device 10 in FIG. Thus, a relatively simple configuration can be obtained.

In other words, the infrared sensor 1 of the infrared detecting device 10 shown in FIG. 14 includes an infrared transmission film 22 that transmits infrared rays on the one surface 1aa side of the thin film portion 1a facing the opening 1f. The infrared sensor 1 has an optical resonance structure in which light is confined and resonated between the infrared transmission film 22 and the first electrode portion 8d, so that the infrared transmission film 22 is an infrared ray on the one surface 1aa side in the thin film portion 1a. It functions as a component constituting the absorbing portion 1m. The infrared sensor 1 is composed of SiO between the infrared transmission film 22 made of a metal thin film (for example, Au thin film) having a thickness of several nanometers and the second electrode portion 8d that also functions as a light reflection film of the infrared detection unit 1n. The thin film portion 1a such as ₂ has an optical resonance structure in which light is confined and resonated. In the optical resonance structure, the temperature rises in the thin film portion 1a between the infrared transmission film 22 and the second electrode portion 8d.

  In the infrared detection device 10 of the present embodiment, only one lens 3 is provided corresponding to the plurality of infrared detection units 1p. However, even if a lens 3 is provided for each of the plurality of infrared detection units 1p. Good.

(Embodiment 8)
The infrared detecting device 10 of the present embodiment shown in FIG. 15 is different from the infrared sensor 1 of the seventh embodiment shown in FIG. 13 in that the infrared detecting device 10 includes a wall 1ba that partitions the opening 1f. In addition, about the component similar to Embodiment 7, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  The infrared sensor 1 of the infrared detecting device 10 of the present embodiment includes a wall 1ba on the base substrate 1b that partitions the opening 1f for each infrared detector 1p corresponding to each of the plurality of infrared detectors 1p. . Thereby, in the infrared detector 10 of this embodiment, it becomes possible to suppress the crosstalk between the adjacent infrared detection parts 1p and 1p, and it becomes possible to raise a sensitivity more.

  Note that the wall 1ba leaves a part of the base substrate 1b when forming the opening 1f in which the one surface 1aa of the base substrate 1b is opened by using an etching technique such as lithography and Deep-RIE. Can be formed.

DESCRIPTION OF SYMBOLS 1 Infrared sensor 1a Thin film part 1aa One surface 1ab Other surface 1b Base board | substrate 1ba Wall part 1c, 1d, 1j, 1k, 1m, 1q, 1r, 1s Infrared absorption part 1e, 1h, 1n, 1p Infrared detection part 1f Opening part 1fa Inner peripheral wall 2 Package base 3 Lens 4 Cover 5 Infrared reflecting film 8d First electrode 8e Second electrode 10 Infrared detector 21 Pyroelectric layer 22 Infrared transmitting film 25 Infrared reflecting layer

Claims (7)

An infrared detection device having an infrared sensor that detects infrared rays, a package base on which the infrared sensor is disposed, and a cover that includes a lens that covers the infrared sensor and focuses infrared rays on the infrared sensor,
The infrared sensor includes a base substrate having an opening provided on one surface side, a thin film portion supported by the base substrate on the other surface side of the base substrate, and an infrared absorption that is provided at least in the thin film portion and absorbs infrared rays. An infrared detector having a portion, and in the thickness direction, at least a part of the infrared absorber is disposed on the thin film portion facing the opening so as to absorb infrared rays from the lens, An infrared detecting device characterized in that the other surface side is the package base side.   The infrared ray reflection film for reflecting the infrared ray from the lens side that is not absorbed by the infrared ray absorbing portion but is transmitted through the infrared ray absorbing portion to the infrared ray absorbing portion side is provided on the package base side. The infrared detection apparatus according to 1.   The infrared detector includes a first electrode portion provided on the other surface side of the thin film portion, a pyroelectric layer provided on the opposite side of the first electrode portion from the thin film portion side, and the pyroelectric layer. The infrared detection device according to claim 1, further comprising: a second electrode portion provided on a side opposite to the first electrode portion side.   The infrared sensor includes an infrared transmission film that transmits a part of infrared rays on the one surface side of the thin film portion facing the opening, and transmits light between the infrared transmission film and the first electrode portion. 4. The optical resonance structure for confining and resonating allows the infrared transmission film to function as a component constituting the infrared absorption part on the one surface side in the thin film part. Infrared detector.   5. The infrared sensor according to claim 1, wherein an infrared reflection layer that reflects infrared rays toward the infrared absorption unit is provided on an inner peripheral wall of the opening of the base substrate. The infrared detection apparatus according to item 1.   The infrared detection apparatus according to claim 1, wherein the infrared sensor includes a plurality of the infrared detection units.   The said infrared sensor was equipped with the wall part which partitions off the said opening part for every said infrared detection part corresponding to each of the said some infrared detection part, The said base board is characterized by the above-mentioned. Infrared detector.

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