Infrared detection element, infrared detector, and infrared type gas sensor

Patent metadata

Field	Value
Publication number	US-9528879-B2
Application number	US-201414761807-A
Country	US
Kind code	B2
Filing date	Jan 20, 2014
Priority date	Jan 21, 2013
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

An infrared detection element includes first and second pyroelectric elements which are arranged in a single pyroelectric substrate. First pyroelectric element includes a first surface electrode, a first back face electrode, and a first portion interposed between first surface and back face electrodes. First portion is provided as part of pyroelectric substrate. Second pyroelectric element includes a second surface electrode, a second back face electrode, and a second portion interposed between second surface and back face electrodes. Second portion is provided as part of pyroelectric substrate. Pyroelectric substrate is provided in part thereof surrounding first pyroelectric element with a slit shaped along an outer periphery of first pyroelectric element. Slit is formed out of regions in which a first surface wiring and a first back face wiring are disposed. Part of pyroelectric substrate surrounding second pyroelectric element is continuously formed over an entire circumference of second portion.

First claim

The invention claimed is:

1. An infrared detection element comprising a first pyroelectric element and a second pyroelectric element,
the first pyroelectric element and the second pyroelectric element being arranged in a single pyroelectric substrate, the first pyroelectric element comprising:
a first surface electrode provided on a surface of the single pyroelectric substrate;
a first back face electrode provided on a back face of the single pyroelectric substrate; and
a first portion interposed between the first surface electrode and the first back face electrode, the first portion being provided as part of the single pyroelectric substrate, the first back face electrode facing the first surface electrode through the first portion,
the second pyroelectric element comprising:
a second surface electrode provided on the surface of the single pyroelectric substrate;
a second back face electrode provided on the back face of the single pyroelectric substrate; and
a second portion interposed between the second surface electrode and the second back face electrode, the second portion being provided as part of the single pyroelectric substrate, the second back face electrode facing the second surface electrode through the second portion,
the single pyroelectric substrate being provided on the surface thereof with a first surface wiring and a second surface wiring that are electrically connected with the first surface electrode and the second surface electrode, respectively,
the single pyroelectric substrate being provided on the back face thereof with a first back face wiring and a second back face wiring that are electrically connected with the first back face electrode and the second back face electrode, respectively,
the single pyroelectric substrate being provided in part thereof surrounding the first pyroelectric element with a slit that is shaped along an outer periphery of the first pyroelectric element, the slit being formed out of regions in which the first surface wiring and the first back face wiring are disposed, and
part of the single pyroelectric substrate surrounding the second pyroelectric element being continuously formed over an entire circumference of the second portion.

2. The infrared detection element according to claim 1 , wherein the slit of the single pyroelectric substrate is at least along a side of the first pyroelectric element, facing the second pyroelectric element.

3. The infrared detection element according to claim 1 , comprising at least two sets of the first pyroelectric element and the second pyroelectric element, the single pyroelectric substrate being formed with the slit at each of facing sides of two adjacent first pyroelectric elements.

4. The infrared detection element according to claim 1 , further comprising an infrared absorption layer for absorbing infrared, which is on the first surface electrode.

5. The infrared detection element according to claim 4 , wherein the first surface electrode and the second surface electrode have sheet resistances that function as infrared reflection layers for reflecting infrared.

6. The infrared detection element according to claim 4 , wherein the infrared absorption layer is provided so as to cover a whole region that is surrounded by the slit in planar view,
the infrared absorption layer is formed of a first resin layer in which at least one kind of conductive fine powder is dispersed in resin, and the at least one kind of conductive fine powder is selected from a group of carbon fine powder, metal fine powder and metal oxide fine powder.

7. An infrared detector, comprising: the infrared detection element according to claim 1 ;
an optical filter disposed in front of the infrared detection element, and configured to transmit infrared having a wavelength band, as a detection object to be detected by the infrared detection element;
a base body on which the infrared detection element is mounted; and
a package that houses the infrared detection element, the optical filter and the base body, the package comprising:
a pedestal that supports the base body;
a cap made of metal, and fixed to the pedestal so as to cover the infrared detection element and the optical filter;
a window hole in a top plate of the cap; and
a window member disposed to close the window hole, the window member allowing infrared to pass through.

8. The infrared detector according to claim 7 , wherein the infrared detection element comprises two sets of the first pyroelectric element for receiving infrared light and the second pyroelectric element for compensating temperature, one set thereof constituting a first detection element, another set thereof constituting a second detection element, and the first detection element and the second detection element being on the single pyroelectric substrate,
the optical filter comprises:
a first optical filter disposed in front of a light receiving surface of the first pyroelectric element of the first detection element; and
a second optical filter disposed in front of a light receiving surface of the first pyroelectric element of the second detection element,

the first detection element and the second detection element respectively comprise first output terminals provided on the surface of the single pyroelectric substrate, the first detection element and the second detection element further respectively comprising second output terminals provided on the back face of the single pyroelectric substrate,
the first output terminals are disposed so as not to overlap with the second output terminals in a thickness direction of the single pyroelectric substrate,
the base body comprises:
an insulation base member having an electric insulation property;
two first lead terminals; and
two second lead terminals, the two first lead terminals and the two first lead terminals being provided integrally with the insulation base member,

the first lead terminals are respectively electrically connected with the first output terminals of the first detection element and the second detection element individually via first bonding portions, each of which is made of a conductive adhesive,
the second lead terminals are respectively electrically connected with the second output terminals of the first detection element and the second detection element individually via second bonding portions, each of which is made of a conductive adhesive,
the insulation base member is provided on a first surface thereof with at least one of:
a projection for positioning the infrared detection element, the projection projecting between each of the first lead terminals and a corresponding second lead terminal, outside an area where the infrared detection element is to be mounted, in a thickness direction of the insulation base member; and
a wall for positioning the infrared detection element, the wall projecting, outside the area where the infrared detection element is to be mounted, in the thickness direction of the insulation base member, a height of the wall being smaller than a thickness of the infrared detection element.

9. The infrared detector according to claim 8 , wherein the insulation base member is provided with a positioning portion for positioning the first optical filter and the second optical filter, and
the positioning portion projects from the first surface of the insulation base member in a direction along a thickness direction of the infrared detection element.

10. The infrared detector according to claim 9 , wherein the positioning portion comprises:
a wall portion for defining positions of the first optical filter and the second optical filter in a direction in which the first optical filter and the second optical filt

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Watabe Yoshifumi
• Sumi Sadayuki
• Inaba Yuichi
• Hozumi Junichi
• Hirai Takahiko
• Kuroda Tsuyoshi

Classifications

• G01J5/34

  using capacitors, e.g. pyroelectric capacitors · CPC title

• G01J5/0831

  Masks; Aperture plates; Spatial light modulators · CPC title

• G01J5/0853

  having infrared absorbers other than the usual absorber layers deposited on infrared detectors like bolometers, wherein the heat propagation between the absorber and the detecting element occurs within a solid · CPC title

• G01J5/0815

  Light concentrators, collectors or condensers · CPC title

• G01J1/0271

  Housings; Attachments or accessories for photometers · CPC title