# US 8,786,042 B2 · Photodetector with a plasmonic structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,042 B2 - Document ID: US8786042B2 - Status: Granted - Kind: B2 - Application number: 12/955,659 - Filed: 2010-11-29 - Published: 2011-06-30 - Granted: 2014-07-22 - Earliest claimed: 2009-12-24 - Assignees: Commissariat A L'energie Atomique Et Aux Energies Alternatives - Applicants: Olivier Gravrand; Gérard Destefanis; Jérôme Le Perchec - Inventors: Olivier Gravrand; Gérard Destefanis; Jérôme Le Perchec - Web page: https://patentgrep.com/patent/US8786042B2 ## CPC - H10F 30/2212: {the devices comprising active layers made of only Group II-VI materials, e.g. HgCdTe infrared photodiodes} - 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 5/10: using electric radiation detectors - G01J 5/20: using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices - H10F 39/1843: {of the hybrid type} - H10F 39/802: {Geometry or disposition of elements in pixels, e.g. address-lines or gate electrodes} - H10F 39/806: {Optical elements or arrangements associated with the image sensors} - H10F 77/148: {Shapes of potential barriers} - H10F 77/206: {for devices having potential barriers} - H10F 77/40: Optical elements or arrangements (surface textures H10F77/70) - Y02E 10/50: Photovoltaic [PV] energy - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - 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) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract This photodetector capable of detecting electromagnetic radiation comprises: a doped semiconductor absorption layer for said radiation, capable of converting said radiation into charge carriers; a reflective layer that reflects the incident radiation that is not absorbed by semiconductor layer towards the latter, located underneath semiconductor layer; and a metallic structure placed on semiconductor layer that forms, with semiconductor layer, a surface Plasmon resonator so as to concentrate the incident electromagnetic radiation on metallic structure in the field concentration zones of semiconductor layer. Semiconductor zones for collecting charge carriers that are oppositely doped to the doping of semiconductor layer are formed in said semiconductor layer and have a topology that complements that of the field concentration zones. ## Claims ### Claim 1 A photo-detector capable of detecting electromagnetic radiation comprising: a doped semiconductor absorption layer for said radiation, capable of converting said radiation into charge carriers; a reflective layer that reflects the incident radiation that is not absorbed by the semiconductor layer towards the latter, located underneath said semiconductor layer; and a metallic structure placed on the semiconductor layer that forms, with said semiconductor layer, a surface plasmon resonator so as to concentrate the incident electromagnetic radiation on the metallic structure in field concentration zones of the semiconductor layer, wherein semiconductor zones for collecting charge carriers are oppositely doped to the doping of the semiconductor layer and are formed in said semiconductor layer in locations of the semiconductor layer that are devoid of field concentration zones and have a topology that complements that of the field concentration zones, and wherein it comprises, for each elementary detection surface of a detection array, a conductor that passes through the photo-detector from the reflective layer to at least one semiconductor collecting zone. ### Claim 2 (depends on 1) The photodetector as claimed in claim 1: wherein the metallic structure comprises spaced-apart structures, the geometry and spacing of the structures relative to each other being selected so that the field concentration zones are produced between the structures; and wherein the semiconductor collecting zones are produced underneath said spaced-apart structures and have the same topology as that of said structure. ### Claim 3 (depends on 2) The photodetector as claimed in claim 2, wherein the structures are located so that they are in contact with the semiconductor collecting zones. ### Claim 4 (depends on 1) The photodetector as claimed in claim 1: wherein the metallic structure comprises spaced-apart structures, the geometry and spacing of said structures relative to each other being selected so that the field concentration zones are produced underneath said structures; and wherein the semiconductor zones are produced between said structures and have the same topology as the space lying between said structure. ### Claim 5 (depends on 4) The photodetector as claimed in claim 4, wherein the semiconductor zones are electrically insulated from the structures, especially by means of a passivation layer. ### Claim 6 (depends on 1) The photodetector as claimed in claim 1, wherein the conductor passes through the semiconductor layer to a structure, said structures which are associated with the elementary detection surface being capable of being electrically connected to each other. ### Claim 7 (depends on 1) The photodetector as claimed in claim 1, wherein the conductor comprises on the same side as reflective layer, a contact pad surface for hybridizing the photodetector on an electronic circuit. ### Claim 8 (depends on 1) The photodetector as claimed in claim 1, wherein the part of the metallic structure associated with each elementary detection surface of a detection array comprises areas having differently orientated parallel patterns, especially areas having patterns that are substantially oriented at right angles relative to each other. ### Claim 9 (depends on 1) The photodetector as claimed in claim 1, wherein a part of the metallic structure associated with each elementary detection surface of a detection array comprises long thin elements forming closed concentric contours, especially contours that have a substantially square or circular shape. ### Claim 10 (depends on 9) The photodetector as claimed in claim 9, wherein the contours have a square shape with an electrical conductor being formed along a diagonal of said contours. ### Claim 11 (depends on 1) The photodetector as claimed in claim 1, wherein a part of the metallic structure associated with each elementary detection surface of a detection array comprises parallel patterns with the orientation of the patterns of one elementary detection surface being different to the orientation of the patterns of the adjacent detection surface, especially at right angles. ### Claim 12 (depends on 1) The photodetector as claimed in claim 1, wherein a part of the metallic structure associated with each elementary detection surface of a detection array comprises parallel patterns with the spatial periodicity of the patterns of one elementary detection surface being different to the spatial periodicity of the patterns of the adjacent elementary detection surface. ### Claim 13 (depends on 1) The photodetector as claimed in claim 1, wherein the semiconductor layer and the semiconductor zones are made of CdZnTe or CdHgTe.