# US 8,772,890 B2 · Apparatus and method of detecting electromagnetic radiation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,890 B2 - Document ID: US8772890B2 - Status: Granted - Kind: B2 - Application number: 12/247,096 - Filed: 2008-10-07 - Published: 2010-04-08 - Granted: 2014-07-08 - Earliest claimed: 2008-10-07 - Assignees: Terasense Group, Inc. - Applicants: Igor Kukushkin; Viacheslav Muravev - Inventors: Igor Kukushkin; Viacheslav Muravev - Web page: https://patentgrep.com/patent/US8772890B2 ## CPC - G01T 1/00: Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation (G01T3/00, G01T5/00 take precedence) - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - H10F 30/222: the potential barrier being a PN heterojunction - H10F 77/14: Shape of semiconductor bodies; Shapes, relative sizes or dispositions of semiconductor regions within semiconductor bodies - H10F 77/146: {Superlattices; Multiple quantum well structures} - H10F 77/147: {Shapes of bodies} - Y02E 10/50: Photovoltaic [PV] energy - G01T: MEASUREMENT OF NUCLEAR OR X-RADIATION (radiation analysis of materials, mass spectrometry G01N23/00; tubes for determining the presence, intensity, density or energy of radiation or particles H01J47/00) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A high speed and miniature detection system, especially for electromagnetic radiation in the GHz and THz range comprises a semiconductor structure having a 2D charge carrier layer or a quasi 2D charge carrier layer with incorporated single or multiple defects, at least first and second contacts to the charge carrier layer, and a device for measuring photovoltage between the first and second contacts. System operation in various embodiments relies on resonant excitation of plasma waves in the semiconductor structure. ## Claims ### Claim 1 A solid state detector apparatus comprising: a semiconductor structure having a charge carrier layer, wherein charge carriers move in two dimensions (2D); at least one defect; and at least a first and a second contact defining a length of said charge carrier layer, said contacts being spaced apart by a distance, wherein the at least one defect and at least one of the first and second contacts define at least two length of regions which can act as resonant plasmon cavities. ### Claim 2 (depends on 1) The detector of claim 1 further comprising: a measuring device capable of being exposed to an incidental electromagnetic radiation, wherein said measuring device is capable of measuring photovoltage or photocurrent between said first and second contacts, an output signal of said measuring device providing information about at least one of (a) the presence of said incidental electromagnetic radiation, and (b) the intensity of said incident electromagnetic radiation. ### Claim 3 (depends on 1) An apparatus in accordance with claim 1, wherein at least one defect comprises a carrier density inhomogeneity. ### Claim 4 (depends on 3) An apparatus in accordance with claim 3, wherein said density inhomogeneity results from the addition of carriers or impurities, or from the removal of carriers or impurities. ### Claim 5 (depends on 3) An apparatus in accordance with claim 3, wherein said density inhomogeneity is created by adding or removing carriers by applying a gate voltage. ### Claim 6 (depends on 5) An apparatus in accordance with claim 5, including means for varying the amplitude of said gate voltage. ### Claim 7 (depends on 1) An apparatus in accordance with claim 1, wherein said defect comprises a restriction or expansion. ### Claim 8 (depends on 1) An apparatus in accordance with claim 1, wherein said defect comprises an inhomogeneity in a carrier layer. ### Claim 9 (depends on 1) An apparatus in accordance with claim 1, wherein said defect comprises charge carrier layer dielectric environment inhomogeneity. ### Claim 10 (depends on 1) An apparatus in accordance with claim 1, wherein said defect comprises a structural inhomogeneity leading to the carrier effective mass inhomogeneity. ### Claim 11 (depends on 1) An apparatus in accordance with claim 1, wherein a plurality of defects are arranged periodically in space. ### Claim 12 (depends on 1) An apparatus in accordance with claim 1, wherein a plurality of defects are arranged non-periodically in space. ### Claim 13 (depends on 1) An apparatus in accordance with claim 1, wherein plurality of additional contacts to said charge carrier layer are provided in addition to said first and second contacts. ### Claim 14 (depends on 1) An apparatus in accordance with claim 1, including means for varying the amplitude of a magnetic field applied to said apparatus. ### Claim 15 (depends on 1) An apparatus in accordance with claim 1, including means for varying the charge density in said charge carrier layer. ### Claim 16 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer is an electron layer. ### Claim 17 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer is a hole layer. ### Claim 18 (depends on 1) An apparatus in accordance with claim 1, wherein said semiconductor structure comprises a GaAs/AlGaAs heterostructure where Ga is gallium, As is arsenic, and Al is aluminum. ### Claim 19 (depends on 1) An apparatus in accordance with claim 1, wherein said semiconductor structure comprises one of a: Si MOSFET structure, an InAs structure, or a Si/Ge structure where Si is silicon, In is indium, As is arsenic, and Ge is germanium. ### Claim 20 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer or said quasi 2D charge carrier layer is realized in the form of a single quantum well. ### Claim 21 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer or said quasi 2D charge carrier layer is realized in the form of a double quantum well. ### Claim 22 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer or said quasi 2D charge carrier layer is realized in the form of a superlattice containing multiple quantum wells. ### Claim 23 (depends on 1) An apparatus in accordance with claim 1, wherein said 2D charge carrier layer or said quasi 2D charge carrier layer is realized in the form of a heterojunction. ### Claim 24 (depends on 1) An apparatus in accordance with claim 1 and comprising a plurality of like detectors formed on one chip. ### Claim 25 (depends on 1) An apparatus of claim 1, further comprising an antenna structure connected to one of said contacts to said change carrier layer. ### Claim 26 (depends on 1) An apparatus in accordance with claim 1 in combination with at least one of a lens, a hom and a waveguide for directing electromagnetic radiation onto said apparatus. ### Claim 27 (depends on 1) An apparatus in accordance with claim 1, further including means for cooling said apparatus to a temperature between ambient temperature and the boiling point of liquid nitrogen. ### Claim 28 (depends on 1) An apparatus in accordance with claim 1 and comprising a plurality of dissimilar detectors formed on one chip. ### Claim 29 (depends on 1) An apparatus according to claim 1 wherein charge carriers are allowed to move in three dimensions due to strong material anisotropy but predominantly move in two dimensions (quasi 2D charge carrier layer). ### Claim 30 (depends on 1) An apparatus according to claim 1, further comprising a barrier layer, wherein the at least one defect and the charge carrier layer are disposed on different sides of the barrier layer.