# US 10,119,865 B2 · Infrared sensor having improved sensitivity and reduced heat generation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,119,865 B2 - Document ID: US10119865B2 - Status: Granted - Kind: B2 - Application number: 14/895,927 - Filed: 2014-05-30 - Published: 2016-06-02 - Granted: 2018-11-06 - Earliest claimed: 2013-06-10 - Assignees: Panasonic Intellectual Property Management Co., Ltd. - Applicants: Panasonic Intellectual Property Management Co., Ltd. - Inventors: Katsumi Kakimoto; Masaaki Saito; Yosuke Hagihara; Takafumi Okudo; Yoichi Nishijima; Ryo Osabe; Naoki Ushiyama; Sumio Akai; Yasufumi Shibata - Web page: https://patentgrep.com/patent/US10119865B2 ## CPC - G01J 5/0853: {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} - G01J 5/0025: {Living bodies (ear thermometers G01J5/0011; detecting, measuring or recording for diagnostic purposes A61B5/00)} - G01J 5/024: {Special manufacturing steps or sacrificial layers or layer structures} - G01J 5/045: {Sealings; Vacuum enclosures; Encapsulated packages; Wafer bonding structures; Getter arrangements (getter arrangements per se H10W76/48, H10P36/03)} - G01J 5/12: using thermoelectric elements, e.g. thermocouples - G01J 5/20: using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices - G01J 2005/106: {Arrays} - G01J 2005/202: {Arrays} - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) ## Abstract An infrared sensor, which achieves a low manufacturing cost, or has high sensitivity, or in which an increase in heat capacity is reduced, is provided. The infrared sensor includes a first infrared absorbing portion, an infrared sensing portion for sensing infrared rays based on infrared rays absorbed by the first infrared absorbing portion, and a plurality of protrusions including metal and disposed apart from each other on a surface of the first infrared absorbing portion. Since an absorption rate of infrared rays is improved, sensitivity can be improved, or an increase in heat capacity can be reduced. ## Claims ### Claim 1 An infrared sensor comprising: a semiconductor substrate; a first infrared absorbing portion provided on the semiconductor substrate, having a first surface facing the semiconductor substrate and a second surface opposite to the first surface; an infrared sensing portion for sensing infrared rays based on infrared rays absorbed by the first infrared absorbing portion; a plurality of protrusions including metal or a silicon nitride film, and disposed apart from each other on the second surface of the first infrared absorbing portion; and a second infrared absorbing portion, which is formed so as to contact and cover a top surface and a side surface of the plurality of protrusions, and which is provided on top surfaces of the first infrared absorbing portion, wherein spaces between adjacent protrusions of the plurality of protrusions are wholly filled with the second infrared absorbing portion such that there is no gap between adjacent protrusions. ### Claim 2 (depends on 1) The infrared sensor of claim 1, wherein the first infrared absorbing portion is provided with a slit in a plan view, and all of the plurality of protrusions are surrounded by the slit. ### Claim 3 (depends on 2) The infrared sensor of claim 2, wherein a distance between neighboring protrusions of the protrusions and the slit is longer than a distance between the neighboring protrusions. ### Claim 4 (depends on 1) The infrared sensor of claim 1, wherein the first infrared absorbing portion is provided with a linear first slit in a plan view, and a part of the plurality of protrusions are disposed along the first slit. ### Claim 5 (depends on 4) The infrared sensor of claim 4, wherein the first infrared absorbing portion is provided with a C-shaped second slit in a plan view, the first infrared absorbing portion is provided with a linear third slit in a plan view, an extending direction of the first slit is perpendicular to an extending direction of the third slit, and a part of the protrusions are disposed along the third slit. ### Claim 6 (depends on 1) The infrared sensor of claim 1, wherein the first infrared absorbing portion is provided with a linear first slit in a plan view, the first infrared absorbing portion is provided with a C-shaped second slit in a plan view, and a part of the plurality of protrusions are disposed to be surrounded by the second slit. ### Claim 7 (depends on 6) The infrared sensor of claim 6, wherein a part of the plurality of protrusions are disposed along the second slit. ### Claim 8 (depends on 6) The infrared sensor of claim 6, wherein the first infrared absorbing portion is provided with a linear third slit in a plan view, an extending direction of the first slit is perpendicular to an extending direction of the third slit, and a part of the protrusions are disposed along the third slit. ### Claim 9 (depends on 1) The infrared sensor of claim 1, wherein the plurality of protrusions are disposed at intervals shorter than a wavelength of infrared rays absorbed by the first infrared absorbing portion. ### Claim 10 (depends on 1) The infrared sensor of claim 1, wherein the first infrared absorbing portion includes an interlayer insulating film, and the plurality of protrusions are disposed on the interlayer insulating film. ### Claim 11 An infrared sensor comprising: a semiconductor substrate; a first infrared absorbing portion provided on the semiconductor substrate, having a first surface facing the semiconductor substrate and second surface opposite to the first surface; an infrared sensing portion for sensing infrared rays based on infrared rays absorbed by the first infrared absorbing portion; a plurality of protrusions including metal or a silicon nitride film, and disposed apart from each other on the second surface of the first infrared absorbing portion; and a single second infrared absorbing portion, which is formed so as to contact and cover an entire top surface and an entire side surface of each of the plurality of protrusions and a top surface of the first infrared absorbing portion, wherein the plurality of protrusions and the single second infrared absorbing portion are made of different materials. ### Claim 12 (depends on 11) The infrared sensor of claim 11, wherein the plurality of protrusions are made of metal including aluminum, the second infrared absorbing portion is made of a non-doped silicate glass or phosphorus silicate glass. ### Claim 13 (depends on 11) The infrared sensor of claim 11, wherein the first infrared absorbing portion is provided with a slit in a plan view, and all of the plurality of protrusions are surrounded by the slit. ### Claim 14 (depends on 13) The infrared sensor of claim 13, wherein a distance between the protrusions and the slit is longer than a distance between neighboring protrusions of the neighboring protrusions. ### Claim 15 (depends on 11) The infrared sensor of claim 11, wherein the first infrared absorbing portion is provided with a linear first slit in a plan view, and a part of the plurality of protrusions are disposed along the first slit. ### Claim 16 (depends on 15) The infrared sensor of claim 15, wherein the first infrared absorbing portion is provided with a C-shaped second slit in a plan view, the first infrared absorbing portion is provided with a linear third slit in a plan view, an extending direction of the first slit is perpendicular to an extending direction of the third slit, and a part of the protrusions are disposed along the third slit. ### Claim 17 (depends on 11) The infrared sensor of claim 11, wherein the first infrared absorbing portion is provided with a linear first slit in a plan view, the first infrared absorbing portion is provided with a C-shaped second slit in a plan view, and a part of the plurality of protrusions are disposed to be surrounded by the second slit. ### Claim 18 (depends on 17) The infrared sensor of claim 17, wherein a part of the plurality of protrusions are disposed along the second slit. ### Claim 19 (depends on 17) The infrared sensor of claim 17, wherein the first infrared absorbing portion is provided with a linear third slit in a plan view, an extending direction of the first slit is perpendicular to an extending direction of the third slit, and a part of the protrusions are disposed along the third slit. ### Claim 20 (depends on 11) The infrared sensor of claim 11, wherein the plurality of protrusions are disposed at intervals shorter than a wavelength of infrared rays absorbed by the first infrared absorbing portion. ### Claim 21 (depends on 11) The infrared sensor of claim 11, wherein the first infrared absorbing portion includes an interlayer insulating film, and the plurality of protrusions disposed on the interlayer insulating film.