Having Graded Composition Patents (Class 257/191)
  • Patent number: 8994071
    Abstract: We have observed anomalous behavior of II-VI semiconductor devices grown on certain semiconductor substrates, and have determined that the anomalous behavior is likely the result of indium atoms from the substrate migrating into the II-V layers during growth. The indium can thus become an unintended dopant in one or more of the II-VI layers grown on the substrate, particularly layers that are close to the growth substrate, and can detrimentally impact device performance. We describe a variety of semiconductor constructions and techniques effective to deplete the migrating indium within a short distance in the growth layers, or to substantially prevent indium from migrating out of the substrate, or to otherwise substantially isolate functional II-VI layers from the migrating indium, so as to maintain good device performance.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: March 31, 2015
    Assignee: 3M Innovative Properties Company
    Inventors: Thomas J. Miller, Michael A. Haase, Xiaoguang Sun
  • Patent number: 8963204
    Abstract: According to one embodiment, a semiconductor device includes a first nitride semiconductor layer, a second nitride semiconductor layer, a third nitride semiconductor layer, an insulating film, an ohmic electrode, and a Schottky electrode. A surface region of the third nitride semiconductor layer between the ohmic electrode and the Schottky electrode contains an element heterogeneous with the constituent element of the third nitride semiconductor layer at a higher concentration than a region of the third nitride semiconductor layer of the second nitride semiconductor layer side.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: February 24, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Yoshioka, Yasunobu Saito, Hidetoshi Fujimoto, Tetsuya Ohno, Toshiyuki Naka
  • Patent number: 8952419
    Abstract: A semiconductor device includes a substrate, a buffer layer on the substrate, and a plurality of nitride semiconductor layers on the buffer layer. The semiconductor device further includes at least one masking layer and at least one inter layer between the plurality of nitride semiconductor layers. The at least one inter layer is on the at least one masking layer.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: February 10, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-jo Tak, Jae-won Lee, Young-soo Park, Jun-youn Kim
  • Patent number: 8946765
    Abstract: Semiconductor structures comprising a III-nitride (e.g., gallium nitride) material region and methods associated with such structures are provided. In some embodiments, the structures include an electrically conductive material (e.g., gold) separated from certain other region(s) of the structure (e.g., a silicon substrate) by a barrier material in order to limit, or prevent, undesirable reactions between the electrically conductive material and the other component(s) which can impair device performance. In certain embodiments, the electrically conductive material may be formed in a via. For example, the via can extend from a topside of the device to a backside so that the electrically conductive material connects a topside contact to a backside contact. The structures described herein may form the basis of a number of semiconductor devices including transistors (e.g., FET), Schottky diodes, light-emitting diodes and laser diodes, amongst others.
    Type: Grant
    Filed: March 21, 2014
    Date of Patent: February 3, 2015
    Assignee: International Rectifier Corporation
    Inventors: Robert Joseph Therrien, Jerry Wayne Johnson, Allen W. Hanson
  • Patent number: 8946775
    Abstract: A nitride semiconductor structure is provided. The nitride semiconductor structure at least includes a silicon substrate, a AlN layer, a AlGaN layer and a GaN layer formed on the AlGaN layer. The silicon substrate has a surface tilted at 0<tilted?0.5° with respect to a axis perpendicular to a (111) crystal plane, and the AlN layer is formed on the surface. The AlGaN layer is formed on the AlN layer. Moreover, an Al content in the AlGaN layer is decreased gradually in a layer thickness direction from the silicon substrate side toward the GaN layer side.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: February 3, 2015
    Assignee: Industrial Technology Research Institute
    Inventors: Chen-Zi Liao, Chih-Wei Hu, Yen-Hsiang Fang, Rong Xuan
  • Patent number: 8890207
    Abstract: System and method for controlling the channel thickness and preventing variations due to formation of small features. An embodiment comprises a fin raised above the substrate and a capping layer is formed over the fin. The channel carriers are repelled from the heavily doped fin and confined within the capping layer. This forms a thin-channel that allows greater electrostatic control of the gate.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: November 18, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Zhiqiang Wu, Ken-Ichi Goto, Wen-Hsing Hsieh, Jon-Hsu Ho, Chih-Ching Wang, Ching-Fang Huang
  • Patent number: 8878244
    Abstract: Gases for film formation are introduced from a plurality of holes provided at a gas nozzle into a processing chamber of a batch-type CVD film-forming apparatus to cause a turbulence of the gases within the processing chamber. In the state where the chamber is kept at a pressure within an atmospheric and quasi-atmospheric pressure region, a silicon-germanium film is epitaxially grown on a semiconductor wafer placed within the processing chamber. Subsequently, a strained silicon film is epitaxially grown on the silicon-germanium film. Thereafter, a semiconductor element is formed in the semiconductor wafer on which the silicon-germanium film and the strained silicon film have been formed, respectively.
    Type: Grant
    Filed: January 3, 2008
    Date of Patent: November 4, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yasuichi Kondo, Wataru Hirasawa, Nobuyuki Sugii
  • Patent number: 8878251
    Abstract: The present invention provides a silicon-compatible compound junctionless field effect transistor enabled to be compatible to a bulk silicon substrate for substituting an expensive SOI substrate, to form a blocking semiconductor layer between a silicon substrate and an active layer by a semiconductor material having a specific difference of energy bandgap from that of the active layer to substitute a prior buried oxide for blocking a leakage current at an off-operation time and to form the active layer by a semiconductor layer having electron or hole mobility higher than that of silicon, and to operate perfectly as a junctionless device though the dopant concentration of the active layer is much lower than the prior junctionless device.
    Type: Grant
    Filed: October 17, 2012
    Date of Patent: November 4, 2014
    Assignees: Seoul National University R&DB Foundation, Kyungpook National University Industry-academic Cooperation Foundation, The Board of Trustees of the Leland Stanford Junior University
    Inventors: Byung-Gook Park, Seongjae Cho, In Man Kang
  • Patent number: 8866189
    Abstract: A silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) is disclosed, including: a substrate; two field oxide regions formed in the substrate; two pseudo buried layers, each being formed under a corresponding one of the field oxide regions; a collector region formed between the field oxide regions, the collector region laterally extending under a corresponding one of the field oxide regions and each side of the collector region being connected with a corresponding one of the pseudo buried layers; a matching layer formed under both the pseudo buried layers and the collector region; and two deep hole electrodes, each being formed in a corresponding one of the field oxide regions, the deep hole electrodes being connected to the corresponding ones of the pseudo buried layers for picking up the collector region. A manufacturing method of the SiGe HBT is also disclosed.
    Type: Grant
    Filed: November 20, 2012
    Date of Patent: October 21, 2014
    Assignee: Shanghai Hua Hong Nec Electronics Co., Ltd.
    Inventors: Jun Hu, Jing Shi, Wensheng Qian, Donghua Liu, Wenting Duan, Fan Chen, Tzuyin Chiu
  • Patent number: 8823055
    Abstract: A method of forming a template on a silicon substrate includes providing a single crystal silicon substrate. The method further includes epitaxially depositing a layer of rare earth oxide on the surface of the silicon substrate. The rare earth oxide being substantially crystal lattice matched to the surface of the silicon substrate. The method further includes forming an aluminum oxide layer on the rare earth oxide, the aluminum oxide being substantially crystal lattice matched to the surface of the rare earth oxide and epitaxially depositing a layer of aluminum nitride (AlN) on the aluminum oxide layer substantially crystal lattice matched to the surface of the aluminum oxide.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: September 2, 2014
    Assignee: Translucent, Inc.
    Inventors: Erdem Arkun, Michael Lebby, Andrew Clark, Rytis Dargis
  • Patent number: 8791542
    Abstract: According to an embodiment, a solid-state imaging device includes a photoelectric, conversion element. The photoelectric conversion element includes a first semiconductor layer, a second semiconductor layer, and a third semiconductor layer. In the solid-state imaging device, D2m3/L2m3×ni32/N2<D1M2/L1M2×ni22/N2 and D1m1/L1m1×ni12/N1<D1m2/L1m2×ni22/N1 are established.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: July 29, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shuichi Toriyama, Koichi Kokubun, Hiroki Sasaki
  • Patent number: 8785942
    Abstract: A nitride semiconductor substrate suitable for a normally-off type high breakdown-voltage device and a method of manufacturing the substrate are provided allowing both a higher threshold voltage and improvement in current collapse. In a nitride semiconductor substrate 10 having a substrate 1, a buffer layer 2 formed on one principal plane of the substrate 1, an intermediate layer 3 formed on the buffer layer 2, an electron transport layer 4 formed on the intermediate layer 3, and an electron supply layer 5 formed on the electron transport layer 4, the intermediate layer 3 has a thickness of 200 nm to 1500 nm and a carbon concentration of 5×1016 atoms/cm3 to 1×1018 atoms/cm3 and is of AlxGa1-xN (0.05?x?0.24), and the electron transport layer 4 has a thickness of 5 nm to 200 nm and is of AlyGa1-yN (0?y?0.04).
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: July 22, 2014
    Assignee: Covalent Materials Corporation
    Inventors: Akira Yoshida, Jun Komiyama, Yoshihisa Abe, Hiroshi Oishi, Kenichi Eriguchi, Shunichi Suzuki
  • Patent number: 8772623
    Abstract: Low bandgap, monolithic, multi-bandgap, optoelectronic devices (10), including PV converters, photodetectors, and LED's, have lattice-matched (LM), double-heterostructure (DH), low-bandgap GaInAs(P) subcells (22, 24) including those that are lattice-mismatched (LMM) to InP, grown on an InP substrate (26) by use of at least one graded lattice constant transition layer (20) of InAsP positioned somewhere between the InP substrate (26) and the LMM subcell(s) (22, 24). These devices are monofacial (10) or bifacial (80) and include monolithic, integrated, modules (MIMs) (190) with a plurality of voltage-matched subcell circuits (262, 264, 266, 270, 272) as well as other variations and embodiments.
    Type: Grant
    Filed: October 30, 2012
    Date of Patent: July 8, 2014
    Assignee: Alliance for Sustainable Energy, LLC
    Inventors: Mark W. Wanlass, Jeffrey J. Carapella
  • Patent number: 8772831
    Abstract: A circuit structure includes a substrate and a patterned dielectric layer over the substrate. The patterned dielectric layer includes a plurality of vias; and a number of group-III group-V (III-V) compound semiconductor layer. The III-V compound semiconductor layers include a first layer in the vias, a second layer over the first layer and the dielectric layer, and a bulk layer over the second layer.
    Type: Grant
    Filed: November 7, 2011
    Date of Patent: July 8, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chi-Ming Chen, Po-Chun Liu, Hung-Ta Lin, Chin-Cheng Chang, Chung-Yi Yu, Chia-Shiung Tsai, Ho-Yung David Hwang
  • Publication number: 20140183451
    Abstract: A semiconductor device includes a channel structure formed on a substrate, the channel structure being formed of a semiconductor material. A gate structure covers at least a portion of the surface of the channel structure and is formed of a film of insulation material and a gate electrode. A source structure is connected to one end of the channel structure, and a drain structure is connected to the other end of the channel structure.
    Type: Application
    Filed: December 19, 2013
    Publication date: July 3, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Tomohiro HIRAI, Shogo Mochizuki, Toshiharu Nagumo
  • Patent number: 8754445
    Abstract: A layer in which the potential level difference normally unrequired for device operation is generated is positively inserted in a device structure. The potential level difference has such a function that even if a semiconductor having a small bandgap is exposed on a mesa side surface, a potential drop amount of the portion is suppressed, and a leakage current inconvenient for device operation can be reduced. This effect can be commonly obtained for a heterostructure bipolar transistor, a photodiode, an electroabsorption modulator, and so on. In the photodiode, since the leakage current is alleviated, the device size can be reduced, so that in addition to improvement of operating speed with a reduction in series resistance, it is advantageous that the device can be densely disposed in an array.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: June 17, 2014
    Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone Corporation
    Inventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Toshihide Yoshimatsu, Haruki Yokoyama
  • Patent number: 8704207
    Abstract: A semiconductor device includes a silicon substrate, an aluminum nitride layer which is arranged on the silicon substrate and has a region where silicon is doped thereof as an impurity, a buffer layer which is arranged on the aluminum nitride layer and has a structure where a plurality of nitride semiconductor films are laminated, and a semiconductor functional layer which is arranged on the buffer layer and made of nitride semiconductor.
    Type: Grant
    Filed: June 8, 2012
    Date of Patent: April 22, 2014
    Assignee: Sanken Electric Co., Ltd.
    Inventors: Masataka Yanagihara, Tetsuji Matsuo
  • Publication number: 20140092635
    Abstract: An AlGaN/GaN HEMT includes: a compound semiconductor layer; a source electrode and a drain electrode formed on an upper side of the compound semiconductor layer; and an Al—Si—N layer being a high-resistance layer disposed in a lower portion of at least one of the source electrode and the drain electrode and higher in an electric resistance value than the source electrode and the drain electrode.
    Type: Application
    Filed: August 16, 2013
    Publication date: April 3, 2014
    Applicants: FUJITSU SEMICONDUCTOR LIMITED, FUJITSU LIMITED
    Inventors: Youichi KAMADA, Kenji Kiuchi
  • Patent number: 8680570
    Abstract: Semiconductor structures comprising a III-nitride (e.g., gallium nitride) material region and methods associated with such structures are provided. In some embodiments, the structures include an electrically conductive material (e.g., gold) separated from certain other region(s) of the structure (e.g., a silicon substrate) by a barrier material in order to limit, or prevent, undesirable reactions between the electrically conductive material and the other component(s) which can impair device performance. In certain embodiments, the electrically conductive material may be formed in a via. For example, the via can extend from a topside of the device to a backside so that the electrically conductive material connects a topside contact to a backside contact. The structures described herein may form the basis of a number of semiconductor devices including transistors (e.g., FET), Schottky diodes, light-emitting diodes and laser diodes, amongst others.
    Type: Grant
    Filed: January 4, 2013
    Date of Patent: March 25, 2014
    Assignee: International Rectifier Corporation
    Inventors: Robert J. Therrien, Jerry W. Johnson, Allen W. Hanson
  • Publication number: 20140077263
    Abstract: According to one embodiment, a semiconductor device includes a first nitride semiconductor layer, a second nitride semiconductor layer, a third nitride semiconductor layer, an insulating film, an ohmic electrode, and a Schottky electrode. A surface region of the third nitride semiconductor layer between the ohmic electrode and the Schottky electrode contains an element heterogeneous with the constituent element of the third nitride semiconductor layer at a higher concentration than a region of the third nitride semiconductor layer of the second nitride semiconductor layer side.
    Type: Application
    Filed: March 5, 2013
    Publication date: March 20, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akira YOSHIOKA, Yasunobu SAITO, Hidetoshi FUJIMOTO, Tetsuya OHNO, Toshiyuki NAKA
  • Patent number: 8674382
    Abstract: A semiconductor light emitting device (10) comprises a semiconductor structure (12) comprising a first body (14) of a first semiconductor material (in this case Ge) comprising a first region of a first doping kind (in this case n) and a second body (18) of a second semiconductor material (in this case Si) comprising a first region of a second doping kind (in this case p). The structure comprises a junction region (15) comprising a first heterojunction (16) formed between the first body (14) and the second body (18) and a pn junction (17) formed between regions of the structure of the first and second doping kinds respectively. A biasing arrangement (20) is connected to the structure for, in use, reverse biasing the pn junction, thereby to cause emission of light.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: March 18, 2014
    Assignee: Insiava (Pty) Limited
    Inventors: Lukas Willem Snyman, Monuko Du Plessis
  • Patent number: 8674407
    Abstract: The present invention provides a semiconductor device having such a structure formed by sequentially laminating a lower barrier layer composed of lattice-relaxed AlxGa1-xN (0?x?1), a channel layer composed of InyGa1-yN (0?y?1) with compressive strain and a contact layer composed of AlzGa1-zN (0?z?1), wherein a two-dimensional electron gas is produced in the vicinity of an interface of said InyGa1-yN channel layer with said AlzGa1-zN contact layer; a gate electrode is formed so as to be embedded in the recessed portion with intervention of an insulating film, which recessed portion is formed by removing a part of said AlzGa1-zN contact layer by etching it away until said InyGa1-yN channel layer is exposed; and, ohmic electrodes are formed on the AlzGa1-zN contact layer. Thus, the semiconductor device has superior uniformity and reproducibility of the threshold voltage while maintaining a low gate leakage current, and is also applicable to the enhancement mode type.
    Type: Grant
    Filed: March 12, 2009
    Date of Patent: March 18, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yuji Ando, Yasuhiro Okamoto, Kazuki Ota, Takashi Inoue, Tatsuo Nakayama, Hironobu Miyamoto
  • Publication number: 20140070275
    Abstract: A semiconductor device includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and third and fourth semiconductor layers of the first conductivity type formed between the first and second semiconductor layer. The first, the third, the fourth, and the second semiconductor layers are coupled in this order. A band gap of the third semiconductor layer is narrower than that of the first semiconductor layer, and a band gap of the fourth semiconductor layer is narrower than that of the third semiconductor layer.
    Type: Application
    Filed: August 21, 2013
    Publication date: March 13, 2014
    Applicant: FUJITSU LIMITED
    Inventor: Tsuyoshi TAKAHASHI
  • Publication number: 20140053894
    Abstract: A method of fabricating a solar cell on a silicon substrate includes providing a crystalline silicon substrate, selecting a grading profile, epitaxially growing a template on the silicon substrate including a single crystal GeSn layer using the grading profile to grade Sn through the layer. The single crystal GeSn layer has a thickness in a range of approximately 3 ?m to approximately 5 ?m. At least two layers of high band gap material are epitaxially and sequentially grown on the template to form at least three junctions. The grading profile starts with the Sn at or near zero with the Ge at zero, the percentage of Sn varies to a maximum mid-area, and reduces the percentage of Sn to zero adjacent an upper surface.
    Type: Application
    Filed: August 23, 2012
    Publication date: February 27, 2014
    Inventors: Radek Roucka, Michael Lebby, Scott Semans
  • Patent number: 8648391
    Abstract: The product of the breakdown voltage (BVCEO) and the cutoff frequency (fT) of a SiGe heterojunction bipolar transistor (HBT) is increased beyond the Johnson limit by utilizing a doped region with a hollow core that extends down from the base to the heavily-doped buried collector region. The doped region and the buried collector region have opposite dopant types.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: February 11, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Jeffrey A. Babcock, Alexei Sadovnikov
  • Publication number: 20130334570
    Abstract: An integrated structure of compound semiconductor devices is disclosed. The integrated structure comprises from bottom to top a substrate, a first epitaxial layer, an etching-stop layer, a second epitaxial layer, a sub-collector layer, a collector layer, a base layer, and an emitter layer, in which the first epitaxial layer is a p-type doped layer, the second epitaxial layer is an n-type graded doping layer with a gradually increased or decreased doping concentration, and the sub-collector layer is an n-type doped layer. The integrated structure can be used to form an HBT, a varactor, or an MESFET.
    Type: Application
    Filed: October 26, 2012
    Publication date: December 19, 2013
    Applicant: WIN SEMICONDUCTORS CORP.
    Inventors: Cheng-Kuo LIN, Szu-Ju LI, Rong-Hao SYU, Shu-Hsiao TSAI
  • Publication number: 20130313608
    Abstract: A layer in which the potential level difference normally unrequired for device operation is generated is positively inserted in a device structure. The potential level difference has such a function that even if a semiconductor having a small bandgap is exposed on a mesa side surface, a potential drop amount of the portion is suppressed, and a leakage current inconvenient for device operation can be reduced. This effect can be commonly obtained for a heterostructure bipolar transistor, a photodiode, an electroabsorption modulator, and so on. In the photodiode, since the leakage current is alleviated, the device size can be reduced, so that in addition to improvement of operating speed with a reduction in series resistance, it is advantageous that the device can be densely disposed in an array.
    Type: Application
    Filed: January 20, 2012
    Publication date: November 28, 2013
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT ELECTRONICS CORPORATION
    Inventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Toshihide Yoshimatsu, Haruki Yokoyama
  • Publication number: 20130313586
    Abstract: A light emitting device comprising a three-dimensional polarization-graded (3DPG) structure that improves lateral current spreading within the device without introducing additional dopant impurities in the epitaxial structures. The 3DPG structure can include a repeatable stack unit that may be repeated several times within the 3DPG. The stack unit includes a compositionally graded layer and a silicon (Si) delta-doped layer. The graded layer is compositionally graded over a distance from a first material to a second material, introducing a polarization-induced bulk charge into the structure. The Si delta-doped layer compensates for back-depletion of the electron gas at the interface of the graded layers and adjacent layers. The 3DPG facilitates lateral current spreading so that current is injected into the entire active region, increasing the number of radiative recombination events in the active region and improving the external quantum efficiency and the wall-plug efficiency of the device.
    Type: Application
    Filed: July 30, 2013
    Publication date: November 28, 2013
    Inventor: Arpan Chakraborty
  • Patent number: 8586859
    Abstract: A method of forming a plurality of discrete, interconnected solar cells mounted on a carrier by providing a first semiconductor substrate; depositing on the first substrate a sequence of layers of semiconductor material forming a solar cell structure; forming a metal back contact layer over the solar cell structure; mounting a carrier on top of the metal back contact; removing the first substrate; and lithographically patterning and etching the solar cell structure to form a plurality of discrete solar cells mounted on the carrier.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: November 19, 2013
    Assignee: Emcore Solar Power, Inc.
    Inventor: Tansen Varghese
  • Patent number: 8575659
    Abstract: A combinationally doped semiconductor layer, a double heterojunction bipolar transistor (DHBT) including a combinationally doped semiconductor layer, and a method of making a combinationally doped semiconductor layer employ a combination of carbon and beryllium doping. The combinationally doped semiconductor layer includes a first sublayer of a semiconductor material doped substantially with beryllium and a second sublayer of the semiconductor material doped substantially with carbon. The DHBT includes a carbon-beryllium combinationally doped semiconductor layer as a base layer. The method of making a combinationally doped semiconductor layer includes growing a first sublayer of the semiconductor layer, the first sublayer being doped substantially with beryllium and growing a second sublayer of the semiconductor layer, the second sublayer being doped substantially with carbon.
    Type: Grant
    Filed: August 13, 2011
    Date of Patent: November 5, 2013
    Assignee: HRL Laboratories, LLC
    Inventors: Steven S. Bui, Tahir Hussain, James Chingwei Li
  • Publication number: 20130256752
    Abstract: A semiconductor device includes: an operation layer that is provided on a substrate and is made of a GaAs-based semiconductor; a first AlGaAs layer provided on the operation layer; a gate electrode provided on the first AlGaAs layer; an second AlGaAs layer having n-type conductivity and provided on the first AlGaAs layer of both sides of the gate electrode, an Al composition ratio of the second AlGaAs layer being larger than that of the first AlGaAs layer and being equal to or more than 0.3 and equal to or less than 0.5; an n-type GaAs layer selectively provided on the second AlGaAs layer; and a source electrode and a drain electrode that contain Au and are provided on the n-type GaAs layer.
    Type: Application
    Filed: March 29, 2013
    Publication date: October 3, 2013
    Applicant: SUMITOMO ELECTRIC DEVICE INNOVATIONS, INC.
    Inventor: SUMITOMO ELECTRIC DEVICE INNOVATIONS, INC.
  • Patent number: 8530995
    Abstract: A high operating temperature split-off band infrared (SPIP) detector having a double and/or graded barrier on either side of the emitter is provided. The photodetector may include a first and second barrier and an emitter disposed between the first and second barriers so as to form a heterojunction at each interface between the emitter and the first and second barriers, respectively. The emitter may be of a first semiconductor material having a split-off response to optical signals, while one of the first or the second barriers may include a double barrier having a light-hole energy band level that is aligned with the split-off band energy level of the emitter. In addition, the remaining barrier may be graded.
    Type: Grant
    Filed: February 3, 2010
    Date of Patent: September 10, 2013
    Assignee: Georgia State University Research Foundation, Inc.
    Inventors: A.G. Unil Perera, Steven G. Matsik
  • Publication number: 20130221406
    Abstract: A solution for forming an ohmic contact to a semiconductor layer is provided. A masking material is applied to a set of contact regions on the surface of the semiconductor layer. Subsequently, one or more layers of a device heterostructure are formed on the non-masked region(s) of the semiconductor layer. The ohmic contact can be formed after the one or more layers of the device heterostructure are formed. The ohmic contact formation can be performed at a processing temperature lower than a temperature range within which a quality of a material forming any semiconductor layer in the device heterostructure is damaged.
    Type: Application
    Filed: February 22, 2013
    Publication date: August 29, 2013
    Applicant: Sensor Electronic Technology, Inc.
    Inventor: Sensor Electronic Technology, Inc.
  • Patent number: 8519437
    Abstract: A light emitting device comprising a three-dimensional polarization-graded (3DPG) structure that improves lateral current spreading within the device without introducing additional dopant impurities in the epitaxial structures. The 3DPG structure can include a repeatable stack unit that may be repeated several times within the 3DPG. The stack unit includes a compositionally graded layer and a silicon (Si) delta-doped layer. The graded layer is compositionally graded over a distance from a first material to a second material, introducing a polarization-induced bulk charge into the structure. The Si delta-doped layer compensates for back-depletion of the electron gas at the interface of the graded layers and adjacent layers. The 3DPG facilitates lateral current spreading so that current is injected into the entire active region, increasing the number of radiative recombination events in the active region and improving the external quantum efficiency and the wall-plug efficiency of the device.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: August 27, 2013
    Assignee: Cree, Inc.
    Inventor: Arpan Chakraborty
  • Patent number: 8507787
    Abstract: A solar cell includes a base layer; an emitter layer disposed on one side of the base layer; a first electrode in electrical communication with the base layer; and a second electrode in electrical communication with the emitter layer, wherein the base layer has a higher doping concentration with increasing distance from the interface between the base layer and the emitter layer, and the base layer has a doping concentration change slope that is further decreased with increasing distance from the interface between the base layer and the emitter layer.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: August 13, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Myoung Gyun Suh
  • Publication number: 20130181256
    Abstract: In an embodiment, a semiconductor device is provided. The semiconductor device may include a substrate having a main processing surface, a first source/drain region comprising a first material of a first conductivity type, a second source/drain region comprising a second material of a second conductivity type, wherein the second conductivity type is different from the first conductivity type, a body region electrically coupled between the first source/drain region and the second source/drain region, wherein the body region extends deeper into the substrate than the first source/drain region in a first direction that is perpendicular to the main processing surface of the substrate, a gate dielectric disposed over the body region, and a gate region disposed over the gate dielectric, wherein the gate region overlaps with at least a part of the first source/drain region and with a part of the body region in the first direction.
    Type: Application
    Filed: March 1, 2013
    Publication date: July 18, 2013
    Applicant: INFINEON TECHNOLOGIES AG
    Inventor: Infineon Technologies AG
  • Patent number: 8487346
    Abstract: A semiconductor device including: a substrate, which has a composition represented by the formula: Ala?Ga1-a?N, wherein a? satisfies 0<a??1; an active layer, which is formed on the substrate, and which has a composition represented by the formula: Alm?Ga1-m?N, wherein m? satisfies 0?m?<1; a buffer layer disposed between the active layer and the substrate; and a first main electrode and a second main electrode, which are formed on the active layer, and which are separated from each other, wherein the semiconductor device is operated by electric current flowing between the first main electrode and the second main electrode in the active layer, and wherein the buffer layer has a composition represented by the formula: AlbIn1-bN, wherein a composition ratio b satisfies 0<b<1, wherein the composition ratio b satisfies m?<b<a?.
    Type: Grant
    Filed: September 16, 2010
    Date of Patent: July 16, 2013
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Ken Sato
  • Patent number: 8471244
    Abstract: A method and system for providing a metal oxide semiconductor (MOS) device are described. The method and system include providing a source, a drain, and a channel residing between the source and the drain. At least a portion of the channel includes an alloy layer including an impurity having a graded concentration. The method and system also include providing a gate dielectric and a gate electrode. At least a portion of the gate dielectric resides above the alloy layer. The gate dielectric resides between the alloy layer and the gate electrode.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: June 25, 2013
    Assignee: Atmel Corporation
    Inventor: Darwin Gene Enicks
  • Patent number: 8466495
    Abstract: Disclosed is an HJFET 110 which comprises: a channel layer 12 composed of InyGa1-yN (0?y?1); a carrier supply layer 13 composed of AlxGa1-xN (0?x?1), the carrier supply layer 13 being provided over the channel layer 12 and including at least one p-type layer; and a source electrode 15S, a drain electrode 15D and a gate electrode 17 which are disposed facing the channel layer 12 through the p-type layer, and provided over the carrier supply layer 13. The following relational expression is satisfied: 5.6×1011x<NA×?×t [cm?2]<5.6×1013x, where x denotes an Al compositional ratio of said carrier supply layer, t denotes a thickness of said p-type layer, NA denotes an impurity concentration, and ? denotes an activation ratio.
    Type: Grant
    Filed: May 10, 2012
    Date of Patent: June 18, 2013
    Assignee: NEC Corporation
    Inventors: Yuji Ando, Hironobu Miyamoto, Tatsuo Nakayama, Yasuhiro Okamoto, Takashi Inoue, Yasuhiro Murase, Kazuki Ota, Akio Wakejima, Naotaka Kuroda
  • Patent number: 8461590
    Abstract: An adverse effect of parasitic capacitance on optical data output from a photodetector circuit is suppressed. A photodetector circuit includes a photoelectric conversion element; a first field-effect transistor; a second field-effect transistor; a first conductive layer functioning as a gate of the first field-effect transistor; an insulating layer provided over the first conductive layer; a semiconductor layer overlapping with the first conductive layer with the insulating layer interposed therebetween; a second conductive layer electrically connected to the semiconductor layer; and a third conductive layer electrically connected to the semiconductor layer, whose pair of side surfaces facing each other overlaps with at least one conductive layer including the first conductive layer with the insulating layer interposed therebetween, and which functions as the other of the source and the drain of the first field-effect transistor.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: June 11, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hikaru Tamura, Yoshiyuki Kurokawa, Takayuki Ikeda
  • Publication number: 20130140604
    Abstract: A silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) is disclosed, including: a substrate; two field oxide regions formed in the substrate; two pseudo buried layers, each being formed under a corresponding one of the field oxide regions; a collector region formed between the field oxide regions, the collector region laterally extending under a corresponding one of the field oxide regions and each side of the collector region being connected with a corresponding one of the pseudo buried layers; a matching layer formed under both the pseudo buried layers and the collector region; and two deep hole electrodes, each being formed in a corresponding one of the field oxide regions, the deep hole electrodes being connected to the corresponding ones of the pseudo buried layers for picking up the collector region. A manufacturing method of the SiGe HBT is also disclosed.
    Type: Application
    Filed: November 20, 2012
    Publication date: June 6, 2013
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shanghai Hua Hong NEC Electronics Co., Ltd.
  • Publication number: 20130126886
    Abstract: A method of fabricating a Schottky diode using gallium nitride (GaN) materials includes providing an n-type GaN substrate having a first surface and a second surface. The second surface opposes the first surface. The method also includes forming an ohmic metal contact electrically coupled to the first surface of the n-type GaN substrate and forming an n-type GaN epitaxial layer coupled to the second surface of the n-type GaN substrate. The method further includes forming an n-type aluminum gallium nitride (AlGaN) surface layer coupled to the n-type GaN epitaxial layer and forming a Schottky contact electrically coupled to the n-type AlGaN surface layer.
    Type: Application
    Filed: November 18, 2011
    Publication date: May 23, 2013
    Applicant: EPOWERSOFT, INC.
    Inventors: Richard J. Brown, Thomas R. Prunty, David P. Bour, Isik C. Kizilyalli, Hui Nie, Andrew P. Edwards, Linda Romano, Madhan Raj
  • Patent number: 8445940
    Abstract: An integrated circuit device is disclosed. The disclosed device provides improved control over a surface proximity and tip depth of integrated circuit devices. An exemplary integrated circuit device disclosed herein has a surface proximity of about 1 nm to about 3 nm and a tip depth of about 5 nm to about 10 nm. The integrated circuit device having such surface proximity and tip depth includes an epi source feature and an epi drain feature defined by a first facet and a second facet of a substrate in a first direction, such as a {111} crystallographic plane of the substrate, and a third facet of the substrate in a second direction, such as a {100} crystallographic plane of the substrate.
    Type: Grant
    Filed: July 9, 2012
    Date of Patent: May 21, 2013
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Ming-Huan Tsai, Hui Ouyang, Chun-Fai Cheng, Wei-Han Fan
  • Patent number: 8436336
    Abstract: The invention provides semiconductor structure comprising a strained Ge channel layer, and a gate dielectric disposed over the strained Ge channel layer. In one aspect of the invention, a strained Ge channel MOSFET is provided. The strained Ge channel MOSFET includes a relaxed SiGe virtual substrate with a Ge content between 50-95%, and a strained Ge channel formed on the virtual substrate. A gate structure is formed upon the strained Ge channel, whereupon a MOSFET is formed with increased performance over bulk Si. In another embodiment of the invention, a semiconductor structure comprising a relaxed Ge channel layer and a virtual substrate, wherein the relaxed Ge channel layer is disposed above the virtual substrate. In a further aspect of the invention, a relaxed Ge channel MOSFET is provided. The method includes providing a relaxed virtual substrate with a Ge composition of approximately 100% and a relaxed Ge channel formed on the virtual substrate.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: May 7, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 8436398
    Abstract: An enhancement-mode GaN transistor, the transistor having a substrate, transition layers, a buffer layer comprised of a III Nitride material, a barrier layer comprised of a III Nitride material, drain and source contacts, a gate containing acceptor type dopant elements, and a diffusion barrier comprised of a III Nitride material between the gate and the buffer layer.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: May 7, 2013
    Assignee: Efficient Power Conversion Corporation
    Inventors: Alexander Lidow, Robert Beach, Guang Y. Zhao, Jianjun Cao
  • Patent number: 8410524
    Abstract: Affords Group III nitride semiconductor devices in which the leakage current from the Schottky electrode can be reduced. In a high electron mobility transistor 11, a supporting substrate 13 is composed of AlN, AlGaN, or GaN, specifically. An AlYGa1?YN epitaxial layer 15 has a full-width-at-half maximum of (0002) plane XRD of 150 sec or less. A GaN epitaxial layer 17 is provided between the gallium nitride supporting substrate and the AlYGa1?YN epitaxial layer (0<Y?1). A Schottky electrode 19 is provided on the AlYGa1?YN epitaxial layer 15. The Schottky electrode 19 constitutes a gate electrode of the high electron mobility transistor 11. The source electrode 21 is provided on the gallium nitride epitaxial layer 15. The drain electrode 23 is provided on the gallium nitride epitaxial layer 15.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: April 2, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tatsuya Tanabe, Kouhei Miura, Makoto Kiyama, Takashi Sakurada
  • Publication number: 20130056795
    Abstract: System and method for controlling the channel thickness and preventing variations due to formation of small features. An embodiment comprises a fin raised above the substrate and a capping layer is formed over the fin. The channel carriers are repelled from the heavily doped fin and confined within the capping layer. This forms a thin-channel that allows greater electrostatic control of the gate.
    Type: Application
    Filed: December 22, 2011
    Publication date: March 7, 2013
    Applicant: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Zhiqiang Wu, Ken-Ichi Goto, Wen-Hsing Hsieh, Jon-Hsu Ho, Chih-Ching Wang, Ching-Fang Huang
  • Patent number: 8377788
    Abstract: A SiGe heterojunction bipolar transistor is fabricated by etching an epitaxially-formed structure to form a mesa that has a collector region, a cap region, and a notched SiGe base region that lies in between. A protective plug is formed in the notch of the SiGe base region so that thick non-conductive regions can be formed on the sides of the collector region and the cap region. Once the non-conductive regions have been formed, the protective plug is removed. An extrinsic base is then formed to lie in the notch and touch the base region, followed by the formation of isolation regions and an emitter region.
    Type: Grant
    Filed: November 15, 2010
    Date of Patent: February 19, 2013
    Assignee: National Semiconductor Corporation
    Inventors: Wibo Van Noort, Jamal Ramdani, Andre Labonte, Donald Robertson Getchell
  • Patent number: 8378384
    Abstract: A wafer includes a wafer frontside surface and a region adjacent to the wafer frontside surface. The region includes oxygen precipitates and the wafer frontside includes a predetermined surface structure to form thereon a device with a desired property.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: February 19, 2013
    Assignee: Infineon Technologies AG
    Inventors: Hans-Joachim Schulze, Hans-Joerg Timme, Helmut Strack
  • Patent number: 8368120
    Abstract: A hybrid device including a silicon based MOSFET operatively connected with a GaN based device.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: February 5, 2013
    Assignee: International Rectifier Corporation
    Inventors: Alexander Lidow, Daniel M. Kinzer, Srikant Sridevan