# US 8,541,818 B2 · Semiconductor heterostructure diodes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,818 B2 - Document ID: US8541818B2 - Status: Granted - Kind: B2 - Application number: 13/533,339 - Filed: 2012-06-26 - Published: 2012-10-25 - Granted: 2013-09-24 - Earliest claimed: 2008-12-10 - Assignees: Transphorm Inc. - Applicants: Yifeng Wu; Umesh Mishra; Primit Parikh; Ilan Ben-Yaacov - Inventors: Yifeng Wu; Umesh Mishra; Primit Parikh; Ilan Ben-Yaacov - Web page: https://patentgrep.com/patent/US8541818B2 ## CPC - H10D 62/105: {by having particular doping profiles, shapes or arrangements of PN junctions; by having supplementary regions, e.g. junction termination extension [JTE] (IGFETs having LDD or drain extension regions H10D30/601)} - H10D 8/60: Schottky-barrier diodes - H10D 30/471: {High electron mobility transistors [HEMT] or high hole mobility transistors [HHMT]} - H10D 62/824: comprising only Group III-V materials heterojunctions, e.g. GaN/AlGaN heterojunctions - H10D 62/8503: {Nitride Group III-V materials, e.g. AlN or GaN} - H10D 84/811: {Combinations of field-effect devices and one or more diodes, capacitors or resistors} - H10D 30/47: having two-dimensional [2D] charge carrier gas channels, e.g. nanoribbon FETs or high electron mobility transistors [HEMT] - H10D 30/475: {having wider bandgap layer formed on top of lower bandgap active layer, e.g. undoped barrier HEMTs such as i-AlGaN/GaN HEMTs} - H10D 30/4755: {having wide bandgap charge-carrier supplying layers, e.g. modulation doped HEMTs such as n-AlGaAs/GaAs HEMTs} - H10D 64/513: {within recesses in the substrate, e.g. trench gates, groove gates or buried gates} - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract Planar Schottky diodes for which the semiconductor material includes a heterojunction which induces a 2 DEG in at least one of the semiconductor layers. A metal anode contact is on top of the upper semiconductor layer and forms a Schottky contact with that layer. A metal cathode contact is connected to the 2 DEG, forming an ohmic contact with the layer containing the 2 DEG. ## Claims ### Claim 1 A diode, comprising: a first III-N material layer; a second III-N material layer on the first III-N material layer, the second III-N material layer being compositionally different from the first III-N material layer, wherein the first and second III-N materials are part of a III-N stack, and a 2 DEG channel is in the second III-N material layer adjacent to the first III-N material layer because of a compositional difference between the first III-N material layer and the second III-N material layer; and a first terminal and a second terminal; wherein the first and second III-N material layers are N-polar or nitrogen-terminated semi-polar material; the first terminal is an anode comprising a Schottky contact with an N-face of the III-N stack; and the second terminal is a single cathode in ohmic contact with the 2 DEG channel. ### Claim 2 (depends on 1) An assembly, comprising: the diode of claim 1; and a high-electron mobility transistor, wherein a terminal of the transistor is electrically connected to the first terminal or the second terminal of the diode. ### Claim 3 (depends on 2) The assembly of claim 2, wherein the terminal of the transistor is a drain, and the drain is electrically connected to the anode of the diode. ### Claim 4 (depends on 1) The diode of claim 1, wherein the first III-N material layer is doped. ### Claim 5 (depends on 1) The diode of claim 1, the III-N stack further comprising a third III-N material layer on the second III-N material layer. ### Claim 6 (depends on 5) The diode of claim 5, wherein the anode forms a Schottky contact with an N-face of the third III-N material layer. ### Claim 7 (depends on 5) The diode of claim 5, wherein a Schottky barrier height of the anode is not substantially reduced when the diode is reverse biased. ### Claim 8 (depends on 5) The diode of claim 5, wherein the third III-N material layer has a first thickness and the second III-N material layer has a second thickness, and the anode extends through an entirety of the first thickness of the third III-N material layer and through an entirety of the second thickness of the second III-N material layer. ### Claim 9 (depends on 1) The diode of claim 1, the second III-N material layer having a thickness, wherein the anode extends through an entirety of the thickness of the second III-N material layer. ### Claim 10 A diode comprising a III-N semiconductor material, an anode Schottky contact, and a cathode contact, wherein a Schottky barrier height of the anode contact is not substantially reduced when the diode is reverse biased as compared to when the anode and cathode contacts are at the same voltage. ### Claim 11 A diode, comprising: a first III-N material layer; a second III-N material layer on the first III-N material layer, the second III-N material layer having a thickness, wherein the first and second III-N materials are part of a III-N stack, a 2 DEG channel is in the second III-N material layer adjacent to the first III-N material layer because of a compositional difference between the first III-N material layer and the second III-N material layer, and the first and second III-N material layers are N-polar or nitrogen-terminated semi-polar material; and two terminals, wherein one terminal is an anode which extends through an entirety of the thickness of the second III-N material layer to contact the first III-N material layer and has extending portions that are on an N-face or nitrogen-terminated semi-polar face of the III-N stack, and one terminal is a single cathode in ohmic contact with the 2 DEG channel. ### Claim 12 (depends on 11) The diode of claim 11, wherein the III-N stack further comprises a third III-N material layer on the second III-N material layer. ### Claim 13 (depends on 12) The diode of claim 12, wherein the extending portions of the anode are on an N-face or nitrogen-terminated semi-polar face of the third III-N material layer. ### Claim 14 (depends on 12) The diode of claim 12, further comprising an insulator layer between the extending portions of the anode and the third III-N material layer. ### Claim 15 (depends on 14) The diode of claim 14, wherein the insulator layer is less than about 7 nm thick. ### Claim 16 (depends on 11) The diode of claim 11, further comprising an insulator layer between the extending portions of the anode and the III-N stack. ### Claim 17 (depends on 16) The diode of claim 16, wherein the insulator layer is less than about 7 nm thick.