# US 8,569,857 B2 · Diode bolometer and method for producing a diode bolometer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,569,857 B2 - Document ID: US8569857B2 - Status: Granted - Kind: B2 - Application number: 12/963,946 - Filed: 2010-12-09 - Published: 2011-06-16 - Granted: 2013-10-29 - Earliest claimed: 2008-06-09 - Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V. - Applicants: Piotr Kropelnicki; Marco Russ; Holger Vogt - Inventors: Piotr Kropelnicki; Marco Russ; Holger Vogt - Web page: https://patentgrep.com/patent/US8569857B2 ## CPC - G01J 5/20: using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices - H10P 90/1914: {using bonding} - 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) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract A bolometer has a semiconductor membrane having a single-crystalline portion, and spacers so as to keep the semiconductor membrane at a predetermined distance from an underlying substrate. The complementarily doped regions of the single-crystalline portion form a diode and the predetermined distance corresponds to a fourth of an infrared wavelength. ## Claims ### Claim 1 A bolometer array comprising pixel elements arranged in columns and rows, each one thereof forming a bolometer, comprising: an underlying substrate; a semiconductor membrane per pixel element, comprising a single-crystalline portion, wherein complementarily doped regions of the single-crystalline portion form a diode and a p-n junction extends between same along a column direction, pixel elements neighboring in the column direction exhibiting equal doping profiles; and a first and a second spacer per pixel element so as to keep the semiconductor membrane at a predetermined distance from the underlying substrate, wherein the predetermined distance corresponds to a fourth of an infrared wavelength, wherein a first and a second edge region via which the semiconductor membrane contacts the spacers and which comprise lands for thermal insulation of the semiconductor membrane, follow the complementarily doped regions laterally on both sides of the p-n junction in each pixel element, and wherein the bolometer additionally comprises an evaluating circuit for each pixel element and at least part of the evaluating circuit is arranged in the underlying substrate laterally between the first and second spacers; wherein in each pixel element the semiconductor membrane additionally comprises a first and a second conductive layer which are electrically insulated from each other by a gap; wherein the first conductive layer contacts the first doped region and the second conductive layer contacts the second doped region, and wherein the gap is formed along the p-n junction between the complementarily doped regions. ### Claim 2 (depends on 1) The bolometer array in accordance with claim 1, wherein additionally an intrinsic region formed laterally along the semiconductor membrane between the complementarily doped regions is provided per pixel element so that the single-crystalline portion forms a PIN diode. ### Claim 3 (depends on 1) The bolometer array in accordance with claim 1, wherein the underlying substrate comprises a reflection layer such that incident infrared radiation is reflectable on the reflection layer in the direction of the semiconductor membrane. ### Claim 4 (depends on 1) The bolometer array in accordance with claim 1, wherein the complementarily doped regions form a sensor area and additionally serve as an absorption medium for the incident infrared radiation. ### Claim 5 (depends on 1) The bolometer array in accordance with claim 1, wherein the complementarily doped regions are arranged on a side of the conductive layer facing away from the underlying substrate. ### Claim 6 (depends on 1) The bolometer array in accordance with claim 1, wherein the conductive layer is implemented such that the semiconductor membrane comprises a sheet resistance between 200 ohm/square area and 700 ohm/square area. ### Claim 7 (depends on 1) The bolometer array in accordance with claim 1, wherein the first and second edge regions comprise an amorphized doped semiconductor material. ### Claim 8 (depends on 1) The bolometer array in accordance with claim 1, wherein the lands comprise a reduced layer thickness compared to the semiconductor membrane. ### Claim 9 (depends on 1) The bolometer array in accordance with claim 1, wherein gaps are formed between the lands and the doped regions. ### Claim 10 (depends on 1) The bolometer array in accordance with claim 1, additionally comprising an insulation layer, wherein the insulation layer is arranged between the conductive layer and the complementarily doped regions or is formed on the semiconductor membrane. ### Claim 11 (depends on 1) The bolometer array in accordance with claim 1, wherein in each pixel element the lands are parallel to the p-n junction. ### Claim 12 (depends on 1) The bolometer array in accordance with claim 1, wherein the edge regions are arranged to be centered between the p-n junctions of pixel elements neighboring in the row direction. ### Claim 13 (depends on 1) The bolometer array in accordance with claim 1, wherein pixel elements neighboring in the row direction comprise complementary doping profiles. ### Claim 14 A bolometer comprising: an underlying substrate; a semiconductor membrane comprising a single-crystalline portion; and a spacer so as to keep the semiconductor membrane at a predetermined distance from the underlying substrate, wherein complementarily doped regions of the single-crystalline portion form a diode and the predetermined distance corresponds to a fourth of an infrared wavelength, wherein the semiconductor membrane contacts the spacers via a first and a second edge region which comprise lands for thermal insulation of the semiconductor membrane, wherein the first and second edge regions comprise an amorphized doped semiconductor material, and wherein the bolometer additionally comprises an evaluating circuit and at least part of the evaluating circuit is arranged in the underlying substrate laterally between the first and second spacers. ### Claim 15 A bolometer comprising: an underlying substrate; a semiconductor membrane comprising a single-crystalline portion; and a spacer so as to keep the semiconductor membrane at a predetermined distance from the underlying substrate, wherein complementarily doped regions of the single-crystalline portion form a diode and the predetermined distance corresponds to a fourth of an infrared wavelength, wherein the semiconductor membrane contacts the spacers via a first and a second edge region which comprise lands for thermal insulation of the semiconductor membrane, wherein the first and second edge regions comprise an amorphized doped semiconductor material, wherein the bolometer additionally comprises an evaluating circuit and at least part of the evaluating circuit is arranged in the underlying substrate laterally between the first and second spacers, and wherein the single-crystalline portion comprises complementarily doped first and second regions forming a diode, and the semiconductor membrane further comprises first and second conductive layers electrically separated from each other with the first conductive layer contacting the first doped region and the second conductive layer contacting the second doped region so that a p-n junction of the diode extends between the first and second conductive layers. ### Claim 16 A bolometer array comprising pixel elements arranged in columns and rows, each one thereof forming a bolometer, comprising: an underlying substrate; a semiconductor membrane per pixel element, comprising a single-crystalline portion, wherein complementarily doped regions of the single-crystalline portion form a diode and a p-n junction extends between same along a column direction, pixel elements neighboring in the column direction exhibiting equal doping profiles; and a first and a second spacer per pixel element so as to keep the semiconductor membrane at a predetermined distance from the underlying substrate, wherein the predetermined distance corresponds to a fourth of an infrared wavelength, wherein a first and a second edge region via which the semiconductor membrane contacts the spacers and which comprise lands for thermal insulation of the semiconductor membrane, follow the complementarily doped regions laterally on both sides of the p-n junction in each pixel element, and wherein the bolometer additionally comprises an evaluating circuit for each pixel element and at least part of the evaluating circuit is arranged in the underlying substrate laterally between the first and second spacers; wherein in each pixel element the semiconductor membrane additionally comprises first and second conductive layers which are electrically separated from each other with the first conductive layer contacting the first doped region and the second conductive layer contacting the second doped region so that the first and second conductive layers are separated from each other along the p-n junction between the complementarily doped regions.