Between Different Group Iv-vi Or Ii-vi Or Iii-v Compounds Other Than Gaas/gaalas Patents (Class 257/201)
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Patent number: 8222675Abstract: A nitride semiconductor device 2 comprises a nitride semiconductor layer 10. A gate insulating film 16 is formed on the surface of the nitride semiconductor layer 10. The gate insulating film 16 includes a portion composed of an aluminum nitride film 15 and a portion composed of an insulating material 14 that contains at least one of oxygen or silicon. A region W2 of the nitride semiconductor layer 10 facing the aluminum nitride film 15 is included in a region W1 of the nitride semiconductor layer 10 facing a gate electrode 18. The nitride semiconductor device 2 may further comprise a nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may be stacked on the surface of the nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may have a larger band gap than that of the nitride semiconductor lower layer 8 and have a heterojunction formed there between.Type: GrantFiled: August 20, 2009Date of Patent: July 17, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Masahiro Sugimoto, Hiroyuki Ueda, Tsutomu Uesugi, Masakazu Kanechika, Tetsu Kachi
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Publication number: 20120175682Abstract: Embodiments of an ohmic contact structure for a Group III nitride semiconductor device and methods of fabrication thereof are disclosed. In one embodiment, the ohmic contact structure has less than or equal to 5%, more preferably less than or equal to 2%, more preferably less than or equal to 1.5%, and even more preferably less than or equal to 1% degradation for 1000 hours High Temperature Soak (HTS) at 300 degrees Celsius. In another embodiment, the ohmic contact structure additionally or alternatively has less than or equal to 10% degradation, more preferably less than or equal to 7.5% degradation, more preferably less than or equal to 6% degradation, more preferably less than or equal to 5% degradation, and even more preferably less than 3% degradation for 1000 hours High Temperature operating Life (HToL) at 225 degrees Celsius and 50 milliamps (mA) per millimeter (mm).Type: ApplicationFiled: July 14, 2011Publication date: July 12, 2012Applicant: CREE, INC.Inventors: Helmut Hagleitner, Daniel Namishia
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Publication number: 20120161205Abstract: A group III nitride semiconductor device and a group III nitride semiconductor wafer are provided. The group III nitride semiconductor device has a channel layer comprising group III nitride-based semiconductor containing Al. The group III nitride semiconductor device can enhance the mobility of the two-dimensional electron gas and improve current characteristics. The group III nitride semiconductor wafer is used to make the group III nitride semiconductor device. The group III nitride semiconductor wafer comprises a substrate made of AlXGa1-XN (0<X?1), a first AlGaN layer made of group III nitride-based semiconductor containing Al and disposed on the substrate, and a second AlGaN layer made of group III nitride-based semiconductor having a bandgap greater than the first AlGaN layer and disposed thereon. The full width at half maximum values of X-ray rocking curves for (0002) and (10-12) planes of the first AlGaN layer are less than 1000 areseconds.Type: ApplicationFiled: March 1, 2012Publication date: June 28, 2012Applicant: Sumitomo Electric Industries, Ltd.Inventors: Shin HASHIMOTO, Tatsuya Tanabe, Katsushi Akita, Hideaki Nakahata, Hiroshi Amano
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Patent number: 8207556Abstract: A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device includes a group III nitride semiconductor supporting base, a GaN based semiconductor region, an active layer, and a GaN semiconductor region. The primary surface of the group III nitride semiconductor supporting base is not any polar plane, and forms a finite angle with a reference plane that is orthogonal to a reference axis extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region, grown on the semipolar primary surface, includes a semiconductor layer of, for example, an n-type GaN based semiconductor doped with silicon. A GaN based semiconductor layer of an oxygen concentration of 5×1016 cm?3 or more provides an active layer, grown on the primary surface, with an excellent crystal quality.Type: GrantFiled: September 23, 2011Date of Patent: June 26, 2012Assignee: Sumitomo Electric Industries, Ltd.Inventors: Takashi Kyono, Yusuke Yoshizumi, Yohei Enya, Katsushi Akita, Masaki Ueno, Takamichi Sumitomo, Takao Nakamura
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Patent number: 8203172Abstract: A nitride semiconductor device includes: a first layer made of a first nitride semiconductor; a second layer provided on the first layer and made of a second nitride semiconductor having a larger band gap than the first nitride semiconductor; a first electrode electrically connected to the second layer; a second electrode provided on the second layer and juxtaposed to the first electrode in a first direction; and a floating electrode provided on the second layer, the floating electrode including: a portion sandwiched by the second electrode in a second direction orthogonal to the first direction; and a portion protruding from the second electrode toward the first electrode.Type: GrantFiled: April 9, 2010Date of Patent: June 19, 2012Assignee: Kabushiki Kaisha ToshibaInventors: Wataru Saito, Yasunobu Saito, Takao Noda, Hidetoshi Fujimoto, Tetsuya Ohno
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Publication number: 20120138952Abstract: A composition, reactor apparatus, method, and control system for growing epitaxial layers of group III-nitride alloys. Super-atmospheric pressure is used as a process parameter to control the epitaxial layer growth where the identity of alloy layers differ within a heterostructure stack of two or more layers.Type: ApplicationFiled: August 12, 2010Publication date: June 7, 2012Applicant: GEORGIA STATE UNIVERSITY RESEARCH FOUNDATION, INC.Inventor: Nikolaus Dietz
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Publication number: 20120132962Abstract: A method of manufacturing a semiconductor device, in which a second semiconductor layer of AlxGa1-x-yInyN (wherein x, y, and x+y satisfy x>0, y?0, and x+y?1, respectively) on a first semiconductor layer of GaN by hetero-epitaxial growth using a MOCVD method, the method including the steps of: (a) supplying N source gas and Ga source gas to form the first semiconductor layer; (b) supplying the N source gas without supplying the Ga source gas and Al source gas, after step (a); (c) supplying the N source gas and the Al source gas without supplying the Ga source gas, after step (b); and (d) supplying the N source gas, the Ga source gas and the Al source gas to form the second semiconductor layer, after step (c).Type: ApplicationFiled: November 30, 2011Publication date: May 31, 2012Applicant: SANKEN ELECTRIC CO., LTDInventor: Ken Sato
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Publication number: 20120126293Abstract: An epitaxial substrate, in which a group of group-III nitride layers is formed on a single-crystal silicon substrate so that a crystal plane is approximately parallel to a substrate surface, comprises: a first group-III nitride layer formed of AlN on the base substrate; a second group-III nitride layer formed of InxxAlyyGazzN (xx+yy+zz=1, 0?xx?1, 0<yy?1 and 0<zz?1) on the first group-III nitride layer; and at least one third group-III nitride layer epitaxially-formed on the second group-III nitride layer, wherein: the first group-III nitride layer is a layer containing multiple defects including at least one type of a columnar crystal, a granular crystal, a columnar domain and a granular domain; and an interface between the first group-III nitride layer and the second group-III nitride layer is a three-dimensional asperity surface.Type: ApplicationFiled: January 19, 2012Publication date: May 24, 2012Applicant: NGK INSULATORS, LTD.Inventors: Shigeaki Sumiya, Makoto Miyoshi, Tomohiko Sugiyama, Mikiya Ichimura, Yoshitaka Kuraoka, Mitsuhiro Tanaka
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Patent number: 8183558Abstract: A compound semiconductor device includes a compound semiconductor substrate; epitaxially grown layers formed over the compound semiconductor substrate and including a channel layer and a resistance lowering cap layer above the channel layer; source and drain electrodes in ohmic contact with the channel layer; recess formed by removing the cap layer between the source and drain electrodes; a first insulating film formed on an upper surface of the cap layer and having side edges at positions retracted from edges, or at same positions as the edges of the cap layer in a direction of departing from the recess; a second insulating film having gate electrode opening and formed covering a semiconductor surface in the recess and the first insulating film; and a gate electrode formed on the recess via the gate electrode opening.Type: GrantFiled: February 8, 2011Date of Patent: May 22, 2012Assignee: Fujitsu LimitedInventors: Kozo Makiyama, Tsuyoshi Takahashi
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Patent number: 8183597Abstract: A GaN semiconductor device which has a low on-resistance, has a very small leak current when a reverse bias voltage is applied and is very excellent in withstand voltage characteristic, said GaN semiconductor device having a structure being provided with a III-V nitride semiconductor layer containing at least one hetero junction structure of III-V nitride semiconductors having different band gap energies; a first anode electrode arranged on a surface of said III-V nitride semiconductor by Schottky junction; a second anode electrode which is arranged on the surface of said III-V nitride semiconductor layer by Schottky junction, is electrically connected with said first anode electrode and forms a higher Schottky barrier than a Schottky barrier formed by said first anode electrode; and an insulating protection film which is brought into contact with said second anode electrode and is arranged on the surface of said III-V nitride semiconductor layer.Type: GrantFiled: May 2, 2005Date of Patent: May 22, 2012Assignee: Furukawa Electric Co., Ltd.Inventors: Nariaki Ikeda, Jiang Li, Seikoh Yoshida
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Patent number: 8173891Abstract: Modeling a monolithic, multi-bandgap, tandem, solar photovoltaic converter or thermophotovoltaic converter by constraining the bandgap value for the bottom subcell to no less than a particular value produces an optimum combination of subcell bandgaps that provide theoretical energy conversion efficiencies nearly as good as unconstrained maximum theoretical conversion efficiency models, but which are more conducive to actual fabrication to achieve such conversion efficiencies than unconstrained model optimum bandgap combinations. Achieving such constrained or unconstrained optimum bandgap combinations includes growth of a graded layer transition from larger lattice constant on the parent substrate to a smaller lattice constant to accommodate higher bandgap upper subcells and at least one graded layer that transitions back to a larger lattice constant to accommodate lower bandgap lower subcells and to counter-strain the epistructure to mitigate epistructure bowing.Type: GrantFiled: May 15, 2008Date of Patent: May 8, 2012Assignee: Alliance for Sustainable Energy, LLCInventors: Mark W. Wanlass, Angelo Mascarenhas
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Publication number: 20120104462Abstract: A semiconductor wafer includes a first semiconductor, and a second semiconductor formed directly or indirectly on the first semiconductor. The second semiconductor contains a first impurity atom exhibiting p-type or n-type conductivity, and a second impurity atom selected such that the Fermi level of the second semiconductor containing both the first and second impurity atoms is closer to the Fermi level of the second semiconductor containing neither the first impurity atom nor the second impurity atom, than the Fermi level of the second semiconductor containing the first impurity atom is. For example, the majority carrier of the second semiconductor is an electron, and the Fermi level of the second semiconductor containing the first and second impurity atoms is lower than the Fermi level of the second semiconductor containing the first impurity atom.Type: ApplicationFiled: November 21, 2011Publication date: May 3, 2012Applicant: SUMITOMO CHEMICAL COMPANY, LIMITEDInventor: Osamu ICHIKAWA
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Patent number: 8168000Abstract: A method of fabricating a III-nitride power semiconductor device which includes selective prevention of the growth of III-nitride semiconductor bodies to selected areas on a substrate in order to reduce stresses and prevent cracking.Type: GrantFiled: June 14, 2006Date of Patent: May 1, 2012Assignee: International Rectifier CorporationInventors: Mike Briere, Robert Beach
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Publication number: 20120100650Abstract: A method for fabricating a semi-polar III-nitride substrate for semi-polar III-nitride device layers, comprising providing a vicinal surface of the III-nitride substrate, so that growth of relaxed heteroepitaxial III-nitride device layers on the vicinal surface compensates for epilayer tilt of the III-nitride device layers caused by one or more misfit dislocations at one or more heterointerfaces between the device layers.Type: ApplicationFiled: October 26, 2011Publication date: April 26, 2012Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: James S. Speck, Anurag Tyagi, Alexey E. Romanov, Shuji Nakamura, Steven P. DenBaars
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Patent number: 8164152Abstract: A liquid crystal display and a method of manufacturing the same are provided. The liquid crystal display includes an insulating substrate, a gate electrode formed on the insulating substrate, an oxide semiconductor layer formed on the gate electrode, an etch stopper formed on the oxide semiconductor layer in a channel area, a common electrode formed on the insulating substrate, source and drain electrodes separated from each other on the etch stopper and extending to an upper portion of the oxide semiconductor layer, a passivation layer formed on the etch stopper, the common electrode, the source and drain electrodes, and a pixel electrode formed on the passivation layer and connected to the drain electrode.Type: GrantFiled: July 27, 2009Date of Patent: April 24, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Je-Hun Lee, Do-Hyun Kim
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Patent number: 8154028Abstract: An infrared external photoemissive detector can have an n-p heterojunction comprising an n-type semiconductor layer and a p-layer; the n-layer semiconductor comprising doped silicon embedded with nanoparticles forming Schottky barriers; and the p-layer is a p-type diamond film. The nanoparticles can be about 20-30 atomic percentage metal particles (such as silver) having an average particle size of about 5-10 nm. The p-layer can have a surface layer that has a negative electron affinity. The n-layer can be in the range of about 3 ?m to 10 ?m thick, and preferably about 3 ?m thick. The doped silicon can be doped with elements selected from the list consisting of phosphorus and antimony.Type: GrantFiled: January 28, 2010Date of Patent: April 10, 2012Assignee: Howard UniversityInventor: Clayton W. Bates, Jr.
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Patent number: 8154052Abstract: In some embodiments of the invention, a device includes a substrate and a semiconductor structure. The substrate includes a wavelength converting element comprising a wavelength converting material disposed in a transparent material, a seed layer comprising a material on which III-nitride material will nucleate, and a bonding layer disposed between the wavelength converting element and the seed layer. The semiconductor structure includes a III-nitride light emitting layer disposed between an n-type region and a p-type region, and is grown on the seed layer.Type: GrantFiled: May 6, 2010Date of Patent: April 10, 2012Assignees: Koninklijke Philips Electronics N.V., Philips Lumileds Lighting Company, LLCInventors: Nathan F. Gardner, Aurelien J. F. David, Oleg B. Shchekin
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Patent number: 8148753Abstract: The present invention provides a compound semiconductor substrate, including: a single-crystal silicon substrate having a crystal face with (111) orientation; a first buffer layer which is formed on the single-crystal silicon substrate and is constituted of an AlxGa1-xN single crystal (0<x?1); a second buffer layer which is formed on the first buffer layer and is composed of a plurality of first unit layers each having a thickness of from 250 nm to 350 nm and constituted of an AlyGa1-yN single crystal (0?y<0.1) and a plurality of second unit layers each having a thickness of from 5 nm to 20 nm and constituted of an AlzGa1-zN single crystal (0.9<z?1), said pluralities of first and second unit layers having been alternately superposed; and a semiconductor device formation region which is formed on the second buffer layer and includes at least one nitride-based semiconductor single-crystal layer.Type: GrantFiled: March 25, 2010Date of Patent: April 3, 2012Assignee: Covalent Materials CorporationInventors: Hiroshi Oishi, Jun Komiyama, Kenichi Eriguchi, Yoshihisa Abe, Akira Yoshida, Shunichi Suzuki
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Patent number: 8148731Abstract: Semiconductor films and structures, such as films and structures utilizing zinc oxide or other metal oxides, and processes for forming such films and structures, are provided for use in metal oxide semiconductor light emitting devices and other metal oxide semiconductor devices, such as ZnO based semiconductor devices.Type: GrantFiled: August 28, 2007Date of Patent: April 3, 2012Assignee: Moxtronics, Inc.Inventors: Yungryel Ryu, Tae-seok Lee, Henry W. White
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Patent number: 8148714Abstract: A method for producing a light-emitting device, includes: performing, on a first substrate made of III-V group compound semiconductor, crystal growth of a laminated body including an etching easy layer contiguous to the first substrate and a light-emitting layer made of nitride semiconductor; bonding a second substrate and the laminated body; and detaching the second substrate provided with the light-emitting layer from the first substrate by, one of removing the etching easy layer by using a solution etching method, and removing the first substrate and the etching easy layer by using mechanical polishing method.Type: GrantFiled: October 19, 2011Date of Patent: April 3, 2012Assignee: Kabushiki Kaisha ToshibaInventor: Ryo Saeki
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Patent number: 8143646Abstract: A stacking fault and twin blocking barrier for forming a III-V device layer on a silicon substrate and the method of manufacture is described. Embodiments of the present invention enable III-V InSb device layers with defect densities below 1×108 cm?2 to be formed on silicon substrates. In an embodiment of the present invention, a buffer layer is positioned between a III-V device layer and a silicon substrate to glide dislocations. In an embodiment of the present invention, GaSb buffer layer is selected on the basis of lattice constant, band gap, and melting point to prevent many lattice defects from propagating out of the buffer into the III-V device layer. In a specific embodiment, a III-V InSb device layer is formed directly on the GaSb buffer.Type: GrantFiled: August 2, 2006Date of Patent: March 27, 2012Assignee: Intel CorporationInventors: Mantu K. Hudait, Mohamad A. Shaheen, Loren A. Chow, Peter G. Tolchinsky, Joel M. Fastenau, Dmitri Loubychev, Amy W. K. Liu
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Publication number: 20120060922Abstract: A non-sintered structure. The non-sintered structure includes a first non-sintered nanocrystal layer, and a second non-sintered nanocrystal layer wherein the first layer and the second layer are configured to interact electronically.Type: ApplicationFiled: March 2, 2009Publication date: March 15, 2012Applicant: The Regents of the University of CaliforniaInventors: Cyrus Wadia, Yue Wu, Paul A. Alivisatos
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Publication number: 20120061728Abstract: Semiconductor-on-insulator (XOI) structures and methods of fabricating XOI structures are provided. Single-crystalline semiconductor is grown on a source substrate, patterned, and transferred onto a target substrate, such as a Si/SiO2 substrate, thereby assembling an XOI substrate. The transfer process can be conducted through a stamping method or a bonding method. Multiple transfers can be carried out to form heterogenous compound semiconductor devices. The single-crystalline semiconductor can be II-IV or III-V compound semiconductor, such as InAs. A thermal oxide layer can be grown on the patterned single crystalline semiconductor, providing improved electrical characteristics and interface properties. In addition, strain tuning is accomplished via a capping layer formed on the single-crystalline semiconductor before transferring the single-crystalline semiconductor to the target substrate.Type: ApplicationFiled: July 1, 2011Publication date: March 15, 2012Applicant: The Regents of the University of CaliforniaInventors: ALI JAVEY, HYUNHYUB KO, KUNIHARU TAKEI
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Patent number: 8134179Abstract: A photodiode in which a pn junction is formed between the doped region (DG) formed in the surface of a crystalline semiconductor substrate and a semiconductor layer (HS) deposited above said doped region. An additional doping (GD) is provided in the edge region of the doped zone, by means of which additional doping the pn junction is shifted deeper into the substrate (SU). With the greater distance of the pn junction from defects at phase boundaries that is achieved in this way, the dark current within the photodiode is reduced.Type: GrantFiled: April 28, 2006Date of Patent: March 13, 2012Assignee: austriamicrosystems AGInventors: Jochen Kraft, Bernhard Löffler, Gerald Meinhardt
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Publication number: 20120037957Abstract: 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: ApplicationFiled: April 30, 2010Publication date: February 16, 2012Inventors: Thomas J. Miller, Michael A. Haase, Xiaoguang Sun
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Patent number: 8115235Abstract: A quantum well (QW) layer is provided in a semiconductive device. The QW layer is provided with a beryllium-doped halo layer in a barrier structure below the QW layer. The semiconductive device includes InGaAs bottom and top barrier layers respectively below and above the QW layer. The semiconductive device also includes a high-k gate dielectric layer that sits on the InP spacer first layer in a gate recess. A process of forming the QW layer includes using an off-cut semiconductive substrate.Type: GrantFiled: February 20, 2009Date of Patent: February 14, 2012Assignee: Intel CorporationInventors: Ravi Pillarisetty, Titash Rakshit, Mantu Hudait, Marko Radosavljevic, Gilbert Dewey, Benjamin Chu-Kung
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Patent number: 8114726Abstract: In a method of forming a gate recess, on a surface of an epitaxial wafer including an epitaxial substrate, having a semiconductor layer having the band gap energy varying therein in the depth-wise direction, and a SiN surface protective layer, having a sidewall forming a gate opening and coating the surface of the epitaxial substrate, ultraviolet light having its energy equivalent to the band gap energy of the specific semiconductor layer is irradiated, while the specific semiconductor layer is photoelectrochemically etched from the gate opening with the SiN surface protective layer used as a mask. The gate recess free from plasma ion-induced damage is thus obtained.Type: GrantFiled: September 28, 2010Date of Patent: February 14, 2012Assignee: Oki Electric Industry Co., Ltd.Inventors: Toshiharu Marui, Hideyuki Okita
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Patent number: 8110427Abstract: A stacked-layered thin film solar cell and a manufacturing method thereof are provided. The stacked-layered thin film solar cell includes a front electrode layer, a stacked-layered light-absorbing structure, and a back electrode layer. The stacked-layered light-absorbing structure has a p-i-n-type layered structure and consists essentially of I-III-VI compounds, wherein the group III elements at least include indium (In) and aluminum (Al). The p-type layer of the stacked-layered light-absorbing structure is near the front electrode layer while the n-type layer is near the back electrode layer. The Al/In concentration ratio in the p-type layer is higher than that in the n-type layer.Type: GrantFiled: October 28, 2009Date of Patent: February 7, 2012Assignee: Nexpower Technology Corp.Inventor: Feng-Chien Hsieh
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Patent number: 8110880Abstract: Systems and methods for single lithography step interconnection metallization using a stop-etch layer are described. A method that includes depositing a stop-etch layer over a semiconductor device, depositing an interconnect metallization material over the stop-etch layer, performing a single lithography step to pattern a mask over the interconnect metallization material, etching the interconnect metallization material in non-masked areas, and removing the stop-etch layer. A system comprises a stop-etch layer material for deposit into a stop-etch layer over a wafer, an interconnect metallization material for deposit over the chrome layer, a lithography operation for patterning a mask over the interconnect metallization material, a first etching compound for etching the interconnect metallization material, where the etching stops at the stop-etch layer, and a second etching compound for removing the stop-etch layer.Type: GrantFiled: February 27, 2009Date of Patent: February 7, 2012Assignee: Northrop Grumman Systems CorporationInventor: John V. Veliadis
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Patent number: 8110482Abstract: A method for improved growth of a semipolar (Al,In,Ga,B)N semiconductor thin film using an intentionally miscut substrate. Specifically, the method comprises intentionally miscutting a substrate, loading a substrate into a reactor, heating the substrate under a flow of nitrogen and/or hydrogen and/or ammonia, depositing an InxGa1-xN nucleation layer on the heated substrate, depositing a semipolar nitride semiconductor thin film on the InxGa1-xN nucleation layer, and cooling the substrate under a nitrogen overpressure.Type: GrantFiled: February 22, 2010Date of Patent: February 7, 2012Assignees: The Regents of the University of California, Japan Science and Technology AgencyInventors: John F. Kaeding, Dong-Seon Lee, Michael Iza, Troy J. Baker, Hitoshi Sato, Benjamin A. Haskell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20120018782Abstract: An objective is to provide a semiconductor device capable of utilizing properties of a high-mobility electron transport layer with a thin film stacked structure having large ?Ec, high electron mobility, and simplified element fabrication process even when the substrate material and the electron transport layer greatly differ in lattice constant. The semiconductor device includes: a semiconductor substrate (1); a first barrier layer (2) on the substrate (1); an electron transport layer (3) on the first barrier layer (2); and a second barrier layer (4) on the electron transport layer (3). The first barrier layer (2) has an InxAl1-xAs layer. At least one of the first barrier layer (2) and the second barrier layer (4) has a stacked structure having an AlyGa1-yAszSb1-z layer in contact with the electron transport layer (3) and an InxAl1-xAs layer in contact with the AlyGa1-yAszSb1-z layer. The stacked structure is doped with a donor impurity.Type: ApplicationFiled: March 31, 2010Publication date: January 26, 2012Inventor: Hirotaka Geka
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Patent number: 8097482Abstract: A method for manufacturing a Group III nitride semiconductor of the present invention, comprising a sputtering step for disposing a substrate and a target in a chamber and forming a Mg-doped Group III nitride semiconductor on the substrate by a reactive sputtering method, wherein the sputtering step includes respective substeps of: a film formation step for forming a semiconductor thin film while doping with Mg; and a plasma treatment step for applying an inert gas plasma treatment to the semiconductor thin film that has been formed in the film formation step, and the Group III nitride semiconductor is formed by laminating the semiconductor thin film through alternate repetitions of the film formation step and the plasma treatment step.Type: GrantFiled: June 3, 2008Date of Patent: January 17, 2012Assignee: Showa Denko K.KInventors: Kenzo Hanawa, Yasumasa Sasaki, Hisayuki Miki
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Patent number: 8093579Abstract: A semiconductor chip (1) comprises a p-doped region (I) having a cladding layer (18) and a contact layer (21) between which a first interlayer (19) and a second interlayer (20) are arranged. A concentration of a first material component (B) within the first and the second interlayer (19, 20) changes in such a way that the band gap varies in a range lying between the band gap of the cladding layer (18) and the band gap of the contact layer (21). A method for producing a semiconductor chip of this type is also disclosed.Type: GrantFiled: May 23, 2008Date of Patent: January 10, 2012Assignee: OSRAM Opto Semiconductors GmbHInventors: Bernd Mayer, Wolfgang Schmid
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Patent number: 8076727Abstract: Methods of forming transparent conducting oxides and devices formed by these methods are shown. Monolayers that contain zinc and monolayers that contain magnesium are deposited onto a substrate and subsequently processed to form magnesium-doped zinc oxide. The resulting transparent conducing oxide includes properties such as an amorphous or nanocrystalline microstructure. Devices that include transparent conducing oxides formed with these methods have better step coverage over substrate topography and more robust film mechanical properties.Type: GrantFiled: February 11, 2009Date of Patent: December 13, 2011Assignee: Micron Technology, Inc.Inventors: Kie Y. Ahn, Leonard Forbes
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Patent number: 8067687Abstract: A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.Type: GrantFiled: December 30, 2004Date of Patent: November 29, 2011Assignee: Alliance for Sustainable Energy, LLCInventor: Mark W. Wanlass
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Publication number: 20110272744Abstract: Described herein are semiconductor structures comprising laterally varying II-VI alloy layer formed over a surface of a substrate. Further, methods are provided for preparing laterally varying II-VI alloy layers over at least a portion of a surface of a substrate comprising contacting at least a portion of a surface of a substrate within a reaction zone with a chemical vapor under suitable reaction conditions to form a laterally varying II-VI alloy layer over the portion of the surface of the substrate, wherein the chemical vapor is generated by heating at least two II-VI binary compounds; and the reaction zone has a temperature gradient of at least 50-100° C. along an extent of the reaction zone. Also described here are devices such as lasers, light emitting diodes, detectors, or solar cells that can use such semiconductor structures.Type: ApplicationFiled: November 6, 2009Publication date: November 10, 2011Applicant: ARIZONA BOARD OF REGENTS, a body corporate acting for and on behalf of ARIZONA STATE UNIVERSITYInventors: Cun-zheng Ning, Anlian Pan
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Publication number: 20110272708Abstract: According to one embodiment, a nitride semiconductor device includes a first, a second and a third semiconductor layer, a first and a second main electrode and a control electrode. The first layer made of a nitride semiconductor of a first conductivity type is provided on a substrate. The second layer made of a nitride semiconductor of a second conductivity type is provided on the first layer. The third layer made of a nitride semiconductor is provided on the second layer. The first electrode is electrically connected with the second layer. The second electrode is provided at a distance from the first electrode and electrically connected with the second layer. The control electrode is provided within a first trench via an insulating film. The first trench is disposed between the first and the second main electrodes, penetrates the third and the second layers, and reaches the first layer.Type: ApplicationFiled: March 21, 2011Publication date: November 10, 2011Applicant: Kabushiki Kaisha ToshibaInventors: Akira Yoshioka, Wataru Saito, Yasunobu Saito, Hidetoshi Fujimoto, Tetsuya Ohno
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Patent number: 8053666Abstract: A p type amorphous silicon layer is stacked, by a CVD method, on a main surface of an n type single-crystalline silicon substrate; an n type amorphous silicon layer is stacked, by the CVD method, on a surface opposite to the surface on which the p type amorphous silicon layer is stacked; and, by using a laser ablation processing method, through-holes are formed in the n type single-crystalline silicon substrate, the p type amorphous silicon layer, and the n type amorphous silicon layer. Subsequently, an insulating layer is formed on an inner wall surface of each of the through-holes, and then a conductive material is filled therein.Type: GrantFiled: May 15, 2008Date of Patent: November 8, 2011Assignee: Sanyo Electric Co., Ltd.Inventor: Yuji Hishida
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Patent number: 8044432Abstract: Methods and devices for fabricating AlGaN/GaN normally-off high electron mobility transistors (HEMTs). A fluorine-based (electronegative ions-based) plasma treatment or low-energy ion implantation is used to modify the drain-side surface field distribution without the use of a field plate electrode. The off-state breakdown voltage can be improved and current collapse can be completely suppressed in LDD-HEMTs with no significant degradation in gains and cutoff frequencies.Type: GrantFiled: November 29, 2006Date of Patent: October 25, 2011Assignee: The Hong Kong University of Science and TechnologyInventors: Jing Chen, Kei May Lau
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Publication number: 20110254057Abstract: Disclosed herein is a nitride based semiconductor device. The nitride based semiconductor device includes: a base substrate; an epitaxial growth layer disposed on the base substrate and having a defect generated due to lattice disparity with the base substrate; a leakage current barrier covering the epitaxial growth layer while filling the defect; and an electrode part disposed on the epitaxial growth layer.Type: ApplicationFiled: July 23, 2010Publication date: October 20, 2011Inventors: Woo Chul Jeon, Ki Yeol Park, Young Hwan Park, Jung Hee Lee
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Patent number: 8039351Abstract: A method of fabricating a hetero-junction bipolar transistor (HBT) is disclosed, where the HBT has a structure incorporating a hetero-junction bipolar structure disposed on a substrate including of silicon crystalline orientation <110>. The hetero-junction bipolar structure may include an emitter, a base and a collector. The substrate may include a shallow-trench-isolation (STI) region and a deep trench region on which the collector is disposed. The substrate may include of a region of silicon crystalline orientation <100> in addition to silicon crystalline orientation <110> to form a composite substrate by using hybrid orientation technology (HOT). The region of crystalline orientation <100> may be disposed on crystalline orientation <110>. Alternatively, the region of silicon crystalline orientation <110> may be disposed on crystalline orientation <100>.Type: GrantFiled: March 26, 2010Date of Patent: October 18, 2011Assignee: International Business Machines CorporationInventors: Thomas N. Adam, Rajendran Krishnasamy
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Patent number: 8035131Abstract: A method for forming a nitride semiconductor laminated structure includes forming a first layer that is an n-type or i-type first layer composed of a group III nitride semiconductor using an H2 carrier gas; forming a second layer by laminating a p-type second layer composed of a group III nitride semiconductor and containing Mg on the first layer using an H2 carrier gas; and forming a third layer that is an n-type or i-type third layer composed of a group III nitride semiconductor on the second layer using an H2 carrier gas after forming the second layer. A method for manufacturing a nitride semiconductor device includes the method steps for forming the nitride semiconductor laminated structure.Type: GrantFiled: March 7, 2008Date of Patent: October 11, 2011Assignee: Rohm Co., Ltd.Inventors: Hirotaka Otake, Hiroaki Ohta, Shin Egami
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Patent number: 8030110Abstract: A nitride semiconductor laser device uses a substrate with low defect density, contains reduced strains inside a nitride semiconductor film, and thus offers a satisfactorily long useful life. On a GaN substrate (10) with a defect density as low as 106 cm?2 or less, a stripe-shaped depressed portion (16) is formed by etching. On this substrate (10), a nitride semiconductor film (11) is grown, and a laser stripe (12) is formed off the area right above the depressed portion (16). With this structure, the laser stripe (12) is free from strains, and the semiconductor laser device offers a long useful life. Moreover, the nitride semiconductor film (11) develops reduced cracks, resulting in a greatly increased yield rate.Type: GrantFiled: December 27, 2010Date of Patent: October 4, 2011Assignee: Sharp Kabushiki KaishaInventors: Takeshi Kamikawa, Eiji Yamada, Masahiro Araki, Yoshika Kaneko
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Patent number: 8026525Abstract: A boron phosphide-based semiconductor light-emitting device includes a substrate of silicon single crystal, a first cubic boron phosphide-based semiconductor layer that is provided on a surface of the substrate and contains twins, a light-emitting layer that is composed of a hexagonal Group III nitride semiconductor and provided on the first cubic boron phosphide-based semiconductor layer and a second cubic boron phosphide-based semiconductor layer that is provided on the light-emitting layer, contains twins and has a conduction type different from that of the first cubic boron phosphide-based semiconductor layer.Type: GrantFiled: March 2, 2005Date of Patent: September 27, 2011Assignee: Showa Denko K.K.Inventor: Takashi Udagawa
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Patent number: 8026581Abstract: Gallium nitride material structures are provided, as well as devices and methods associated with such structures. The structures include a diamond region which may facilitate conduction and removal of heat generated within the gallium nitride material during device operation. The structures described herein may form the basis of a number of semiconductor devices and, in particular, transistors (e.g., FETs).Type: GrantFiled: February 5, 2008Date of Patent: September 27, 2011Assignee: International Rectifier CorporationInventors: Allen W. Hanson, Edwin Lanier Piner
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Publication number: 20110220967Abstract: A method for forming a low defect density heterojunction between a first and a second compound, the first and second compounds each includes a group III element combined with a group V element in the periodic table, the method includes the steps of introducing in the deposition chamber the flux of the group III element for the first compound at substantially the same time while introducing in the deposition chamber a flux of the group V element for the second compound, stopping the flux of the group III element for the first compound after a first predetermined time period, stopping the flux of the group V element for the first compound after a second predetermined time period, and introducing in the deposition chamber a flux of the group III element the group V element for the second compound.Type: ApplicationFiled: May 24, 2011Publication date: September 15, 2011Applicant: Teledyne Licensing, LLCInventors: Gerard J. Sullivan, Amal Ikhlassi, Joshua I. Bergman, Berinder Brar, Gabor Nagy
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Publication number: 20110210378Abstract: A high electron mobility transistor includes a free-standing supporting base having a III nitride region, a first III nitride barrier layer which is provided on the first III nitride barrier layer, a III nitride channel layer which is provided on the first III nitride barrier layer and forms a first heterojunction with the first III nitride barrier layer, a gate electrode provided on the III nitride channel layer so as to exert an electric field on the first heterojunction, a source electrode on the III nitride channel layer and the first III nitride barrier, and a drain electrode on the III nitride channel layer and the first III nitride barrier. The III nitride channel layer has compressive internal strain, and the piezoelectric field of the III nitride channel layer is oriented in the direction from the supporting base towards the first III nitride barrier layer.Type: ApplicationFiled: July 29, 2010Publication date: September 1, 2011Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Masaki UENO, Takashi KYONO, Yohei ENYA, Takamichi SUMITOMO, Yusuke YOSHIZUMI
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Publication number: 20110193135Abstract: A method of forming a semiconductor device, the method comprising providing a semiconductor layer, and providing a first layer of a first metal on the semiconductor layer. A second layer may be provided on the first layer of the first metal. The second layer may include a layer of silicon and a layer of a second metal, and the first and second metals may be different. The first metal may be titanium and the second metal may be nickel. Related devices, structures, and other methods are also discussed.Type: ApplicationFiled: February 11, 2010Publication date: August 11, 2011Inventors: Helmut Hagleitner, Zoltan Ring, Scott Sheppard, Jason Henning, Jason Gurganus, Dan Namishia
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Patent number: 7994512Abstract: New Group III based diodes are disclosed having a low on state voltage (Vf) and structures to keep reverse current (Irev) relatively low. One embodiment of the invention is Schottky barrier diode made from the GaN material system in which the Fermi level (or surface potential) of is not pinned. The barrier potential at the metal-to-semiconductor junction varies depending on the type of metal used and using particular metals lowers the diode's Schottky barrier potential and results in a Vf in the range of 0.1-0.3V. In another embodiment a trench structure is formed on the Schottky diodes semiconductor material to reduce reverse leakage current. and comprises a number of parallel, equally spaced trenches with mesa regions between adjacent trenches. A third embodiment of the invention provides a GaN tunnel diode with a low Vf resulting from the tunneling of electrons through the barrier potential, instead of over it. This embodiment can also have a trench structure to reduce reverse leakage current.Type: GrantFiled: June 30, 2005Date of Patent: August 9, 2011Assignee: Cree, Inc.Inventors: Primit Parikh, Umesh Mishra
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Patent number: 7989842Abstract: The disclosure relates to a zero-bias heterojunction diode detector with varying impedance. The detector includes a substrate supporting a Schottky structure and an Ohmic contact layer. A metallic contact layer is formed over the Ohmic layer. The Schottky structure comprises a plurality of barrier layers and each of the plurality of barriers layers includes a first material and a second material. In one embodiment, the composition percentage of the second material in each of the barrier layers increases among the plurality of barrier layers from the substrate to the metal layer in order to provide a graded periodicity for the Schottky structure.Type: GrantFiled: February 27, 2009Date of Patent: August 2, 2011Assignee: Teledyne Scientific & Imaging, LLCInventors: Hooman Kazemi, Chanh Nguyen, Berinder Brar