With Specified Schottky Metal Patents (Class 257/473)
  • Patent number: 7999346
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicide formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Grant
    Filed: June 17, 2010
    Date of Patent: August 16, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Yuji Okamura, Masashi Matsushita
  • Patent number: 7985615
    Abstract: The present invention relates to embodiments of TPV cell structures based on carbon nanotube and nanowire materials. One embodiment according to the present invention is a p-n junction carbon nanotube/nanowire TPV cell, which is formed by p-n junction wires. A second embodiment according to the present invention is a carbon nanotube/nanowire used as a p-type (or n-type), and using bulk material as the other complementary type to a form p-n junction TPV cell. A third embodiment according to the present invention uses a controllable Schottky barrier height between a one-dimensional nanowire and a metal contact to form the built-in potential of the TPV cells.
    Type: Grant
    Filed: November 20, 2006
    Date of Patent: July 26, 2011
    Assignee: The Regents of the University of California
    Inventors: Fei Liu, Ma Siguang, Kang L. Wang
  • Patent number: 7982209
    Abstract: A rewritable nonvolatile memory cell is disclosed comprising a steering element in series with a carbon nanotube fabric. The steering element is preferably a diode, but may also be a transistor. The carbon nanotube fabric reversibly changes resistivity when subjected to an appropriate electrical pulse. The different resistivity states of the carbon nanotube fabric can be sensed, and can correspond to distinct data states of the memory cell. A first memory level of such memory cells can be monolithically formed above a substrate, a second memory level monolithically formed above the first, and so on, forming a highly dense monolithic three dimensional memory array of stacked memory levels.
    Type: Grant
    Filed: March 27, 2007
    Date of Patent: July 19, 2011
    Assignee: SanDisk 3D LLC
    Inventors: S. Brad Herner, Roy E. Scheuerlein
  • Publication number: 20110085577
    Abstract: A hybrid integrated optical device includes a substrate comprising a silicon layer and a compound semiconductor device bonded to the silicon layer. The device also includes a bonding region disposed between the silicon layer and the compound semiconductor device. The bonding region includes a metal-semiconductor bond at a first portion of the bonding region. The metal-semiconductor bond includes a first pad bonded to the silicon layer, a bonding metal bonded to the first pad, and a second pad bonded to the bonding metal and the compound semiconductor device. The bonding region also includes an interface assisted bond at a second portion of the bonding region. The interface assisted bond includes an interface layer positioned between the silicon layer and the compound semiconductor device, wherein the interface assisted bond provides an ohmic contact between the silicon layer and the compound semiconductor device.
    Type: Application
    Filed: October 12, 2010
    Publication date: April 14, 2011
    Applicant: Skorpios Technologies, Inc.
    Inventors: Stephen B. Krasulick, John Dallesasse
  • Publication number: 20110031579
    Abstract: A method of making a diode begins by depositing an AlxGa1-xN nucleation layer on a SiC substrate, then depositing an n+ GaN buffer layer, an n? GaN layer, an AlxGa1-xN barrier layer, and an SiO2 dielectric layer. A portion of the dielectric layer is removed and a Schottky metal deposited in the void. The dielectric layer is affixed to the support layer with a metal bonding layer using an Au—Sn utectic wafer bonding process, the substrate is removed using reactive ion etching to expose the n+ layer, selected portions of the n+, n?, and barrier layers are removed to form a mesa diode structure on the dielectric layer over the Schottky metal, and an ohmic contact is deposited on the n+ layer.
    Type: Application
    Filed: October 15, 2010
    Publication date: February 10, 2011
    Inventors: Primit Parikh, Sten Heikman
  • Publication number: 20110006307
    Abstract: A group III-nitride semiconductor Schottky diode comprises a conducting substrate having a first surface, a stack of multiple layers including a buffer layer and a semiconductor layer sequentially formed on the first surface, wherein the semiconductor layer comprises a group III nitride compound, a first electrode on the semiconductor layer, and a second electrode formed in contact with the first surface at a position adjacent to the stack of multiple layers. In other embodiments, the application also describes a method of fabricating the group III-nitride semiconductor Schottky diode.
    Type: Application
    Filed: July 1, 2010
    Publication date: January 13, 2011
    Applicant: TEKCORE CO., LTD.
    Inventors: Guan-Ting CHEN, Chia-Ming LEE
  • Patent number: 7851830
    Abstract: A multigate Schottky diode comprising an electrically conducting active semiconductor region; first and second electrically connected metallic contact arms on the active semiconductor region forming ohmic contacts therewith; the ohmic contacts being spaced apart on the active semiconductor region to define a gate receiving channel therebetween. a plurality of electrically connected metallic gate fingers, the metallic gate fingers being in contact with the active semiconductor region to form Schottky junctions, the Schottky junctions being spaced apart on the active semiconductor region and extending at least partially along the gate receiving channel.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: December 14, 2010
    Assignee: RFMD (UK) Limited
    Inventors: Ronald Arnold, Dennis Michael Brookbanks
  • Patent number: 7829970
    Abstract: A junction barrier Schottky diode has an N-type well having surface and a first impurity concentration; a p-type anode region in the surface of the well, and having a second impurity concentration; and an N-type cathode region in the surface of the well and horizontally abutting the anode region, and having a third impurity concentration. A first N-type region vertically abuts the anode and cathode regions, and has a fourth impurity concentration. An ohmic contact is made to the anode and a Schottky contact is made to the cathode. The fourth impurity concentration is less than the first, second and third impurity concentrations.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: November 9, 2010
    Assignee: Intersil Americas Inc.
    Inventors: Dev Alok Girdhar, Michael David Church
  • Publication number: 20100207232
    Abstract: A gallium nitride based semiconductor diode includes a substrate, a semiconductor body including a first heavily doped GaN layer and a second lightly doped GaN layer. The semiconductor body includes mesas projecting upwardly from a lower surface where each of the mesas includes the second GaN layer and a portion of the first GaN layer. Schottky contacts are formed on the upper surface of the mesas and ohmic contacts are formed on the lower surface of the semiconductor body. An insulating layer is formed over the Schottky and ohmic contacts and vias are formed in the insulating layer to the Schottky and Ohmic contacts. A first metal pad is formed in a third metal layer and over vias to the Schottky contacts to form an anode electrode. A second metal pad is formed in the third metal layer and over vias to the ohmic contacts to form a cathode electrode.
    Type: Application
    Filed: February 18, 2009
    Publication date: August 19, 2010
    Applicant: ALPHA & OMEGA SEMICONDUCTOR, INC.
    Inventor: TingGang Zhu
  • Patent number: 7777292
    Abstract: A semiconductor device includes a semiconductor substrate of a first conductivity type having a top surface and a bottom surface, a semiconductor layer of a first conductivity type formed on the top surface of the semiconductor substrate, and having an active region and an edge termination region surrounding the active region, a first semiconductor region of a second conductivity type formed in the edge termination region adjacent to an edge of the active region, a second semiconductor region of a second conductivity type buried in the edge termination region in a sheet shape or a mesh shape substantially in parallel with a surface of the semiconductor layer, a first electrode formed on the active region of the semiconductor layer and a part of the first semiconductor region, and a second electrode formed on the bottom surface of the semiconductor substrate.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: August 17, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Chiharu Ota, Johji Nishio, Tetsuo Hatakeyama, Takashi Shinohe
  • Patent number: 7768092
    Abstract: A semiconductor device comprises a first layer (1) of a wide band gap semiconductor material doped according to a first conductivity type and a second layer (3) on top thereof designed to form a junction blocking current in the reverse biased state of the device at the interface to said first layer. The device comprises extension means for extending a termination of the junction laterally with respect to the lateral border (6) of the second layer. This extension means comprises a plurality of rings (16-21) in juxtaposition laterally surrounding said junction (15) and being arranged as seen in the lateral direction away from said junction alternatively a ring (16-18) of a semiconductor material of a second conductivity type opposite to that of said first layer and a ring (19-21) of a semi-insulating material.
    Type: Grant
    Filed: July 20, 2005
    Date of Patent: August 3, 2010
    Assignee: Cree Sweden AB
    Inventors: Christopher Harris, Cem Basceri
  • Patent number: 7728403
    Abstract: A semiconductor device of unipolar type has Schottky-contacts (6) laterally separated by regions in the form of additional layers (7, 7?) of semiconductor material on top of a drift layer (3). Said additional layers being doped according to a conductivity type being opposite to the one of the drift layer. At least one (7?) of the additional layers has a substantially larger lateral extension and thereby larger area of the interface to the drift layer than adjacent such layers (7) for facilitating the building-up of a sufficient voltage between that layer and the drift layer for injecting minority charge carriers into the drift layer upon surge for surge protection.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: June 1, 2010
    Assignee: Cree Sweden AB
    Inventors: Christopher Harris, Cem Basceri, Kent Bertilsson
  • Publication number: 20100117186
    Abstract: The invention provides a semiconductor device and a method for fabricating the same capable of preventing a field plate portion from being delaminated from an insulating film by stress inherent in a semiconductor layer even if the stress is released in forming a trench in part of the semiconductor layer where the semiconductor device is to be separated and capable of having a higher breakdown property of the semiconductor device. The semiconductor device has source, drain and gate electrodes, insulating films that insulate the electrodes on an electron supplying layer and a mesa-structure formed at part where the semiconductor device is to be separated. The gate electrode has a first electrode layer having a function of the electrode and a second electrode layer having a field plate portion whose part that contacts with the insulating film is made of a metallic material that adheres well to the insulating film.
    Type: Application
    Filed: June 24, 2009
    Publication date: May 13, 2010
    Inventors: Hiroshi Kambayashi, Shusuke Kaya, Nariaki Ikeda
  • Patent number: 7615839
    Abstract: Since VF and IR characteristics of a Schottky barrier diode are in a trade-off relationship, there has heretofore been a problem that an increase in a leak current is unavoidable in order to realize a low VF. Moreover, there has been a known structure which suppresses the leak current in such a manner that a depletion layer is spread by providing P+ regions and a pinch-off effect is utilized. However, in reality, it is difficult to completely pinch off the depletion layer. P+ type regions are provided, and a low VF Schottky metal layer is allowed to come into contact with the P+ type regions and depletion regions therearound. A low IR Schottky metal layer is allowed to come into contact with a surface of a N type substrate between the depletion regions. When a forward bias is applied, a current flows through the metal layer of low VF characteristic. When a reverse bias is applied, a current path narrowed by the depletion regions is formed only in the metal layer portion of low IR characteristic.
    Type: Grant
    Filed: February 16, 2005
    Date of Patent: November 10, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tadaaki Souma, Tadashi Natsume
  • Patent number: 7612426
    Abstract: A Schottky barrier diode includes a first semiconductor layer and a second semiconductor layer successively formed above a semiconductor substrate with a buffer layer formed between the first and second semiconductor layers and the semiconductor substrate. A Schottky electrode and an ohmic electrode spaced from each other are formed on the second semiconductor layer, and a back face electrode is formed on the back face of the semiconductor substrate. The Schottky electrode or the ohmic electrode is electrically connected to the back face electrode through a via penetrating through at least the buffer layer.
    Type: Grant
    Filed: November 15, 2005
    Date of Patent: November 3, 2009
    Assignee: Panasonic Corporation
    Inventors: Manabu Yanagihara, Yasuhiro Uemoto, Tsuyoshi Tanaka, Daisuke Ueda
  • Patent number: 7511352
    Abstract: A monolithic three dimensional memory array comprising Schottky diodes components separated by antifuses is disclosed. The Schottky diodes are vertically oriented and disposed on alternating levels. Those on odd levels are “rightside-up” with antifuse over the metal, and those on even levels are “upside down” with metal over the antifuse. Both antifuses are preferably grown oxides.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: March 31, 2009
    Assignee: Sandisk 3D LLC
    Inventor: Michael A. Vyvoda
  • Patent number: 7476956
    Abstract: 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: Grant
    Filed: May 20, 2003
    Date of Patent: January 13, 2009
    Assignee: Cree, Inc.
    Inventors: Primit Parikh, Umesh Mishra
  • Patent number: 7436039
    Abstract: A gallium nitride based semiconductor Schottky diode fabricated from a n+ doped GaN layer having a thickness between one and six microns disposed on a sapphire substrate; an n? doped GaN layer having a thickness greater than one micron disposed on said n+ GaN layer patterned into a plurality of elongated fingers and a metal layer disposed on the n? doped GaN layer and forming a Schottky junction therewith. The layer thicknesses and the length and width of the elongated fingers are optimized to achieve a device with breakdown voltage of greater than 500 volts, current capacity in excess of one ampere, and a forward voltage of less than three volts.
    Type: Grant
    Filed: January 6, 2005
    Date of Patent: October 14, 2008
    Assignee: Velox Semiconductor Corporation
    Inventors: TingGang Zhu, Bryan S. Shelton, Marek K. Pabisz, Mark Gottfried, Linlin Liu, Milan Pophristic, Michael Murphy, Richard A. Stall
  • Patent number: 7385271
    Abstract: Electro-hole production at a Schottky barrier has recently been observed experimentally as a result of chemical processes. This conversion of chemical energy to electronic energy may serve as a basic link between chemistry and electronics and offers the potential for generation of unique electronic signatures for chemical reactions and the creation of a new class of solide state chemical sensors. Detection of the following chemical species was established: hydrogen, deuterium, carbon monoxide, molecular oxygen. The detector (1b) consists of a Schottky diode between an Si layer and an ultrathin metal layer with zero force electrical contacts.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: June 10, 2008
    Assignee: Adrena, Inc.
    Inventors: Eric W. McFarland, Henry W. Weinberg, Hermann Nienhaus, Howard S. Bergh, Brian Gergen, Arunava Mujumdar
  • Patent number: 7355260
    Abstract: A conductive layer includes a first portion that forms a Schottky region with an underlying first region having a first conductivity type. A second region of a second conductivity type underlies the first region, where the second conductivity type is opposite the first conductivity type. A third region of the first conductivity type immediately underlies the second region and is electrically coupled to a cathode of the device.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: April 8, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Vishnu K. Khemka, Vijay Parthasarathy, Ronghua Zhu, Amitava Bose
  • Patent number: 7312510
    Abstract: A device using an ambipolar transport of an SB-MOSFET and a method for operating the same are provided. The SB-MOSFET includes: a silicon channel region; a source and a drain contacted on both sides of the channel region and formed of material including metal layer; and a gate formed on the channel region, with a gate dielectric layer interposed therebetween. Positive (+), 0 or negative (?) gate voltage is selectively applied to the gate, the channel becomes off-state when the gate voltage between a negative threshold voltage and a positive threshold voltage is applied, and the channel becomes a first on-state and a second on-state when the gate voltage is lower than the negative threshold voltage or higher than the positive threshold voltage. Accordingly, it is possible to implement three current states, that is, hole current, electron current, and no current. The SB-MOSFET can be applied to a multi-bit memory and/or multi-bit logic device.
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: December 25, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jae Heon Shin, Moon Gyu Jang, Yark Yeon Kim, Seong Jae Lee
  • Publication number: 20070278609
    Abstract: A semiconductor device of unipolar type has Schottky-contacts (6) laterally separated by regions in the form of additional layers (7, 7?) of semiconductor material on top of a drift layer (3). Said additional layers being doped according to a conductivity type being opposite to the one of the drift layer. At least one (7?) of the additional layers has a substantially larger lateral extension and thereby larger area of the interface to the drift layer than adjacent such layers (7) for facilitating the building-up of a sufficient voltage between that layer and the drift layer for injecting minority charge carriers into the drift layer upon surge for surge protection.
    Type: Application
    Filed: May 31, 2006
    Publication date: December 6, 2007
    Inventors: Christopher Harris, Cem Basceri, Kent Bertilsson
  • Patent number: 7274083
    Abstract: A wide bandgap semiconductor device with surge current protection and a method of making the device are described. The device comprises a low doped n-type region formed by plasma etching through the first epitaxial layer grown on a heavily doped n-type substrate and a plurality of heavily doped p-type regions formed by plasma etching through the second epitaxial layer grown on the first epitaxial layer. Ohmic contacts are formed on p-type regions and on the backside of the n-type substrate. Schottky contacts are formed on the top surface of the n-type region. At normal operating conditions, the current in the device flows through the Schottky contacts. The device, however, is capable of withstanding extremely high current densities due to conductivity modulation caused by minority carrier injection from p-type regions.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: September 25, 2007
    Assignee: Semisouth Laboratories, Inc.
    Inventors: Igor Sankin, Joseph Neil Merrett
  • Patent number: 7274082
    Abstract: Electron-hole production at a Schottky barrier has recently been observed experimentally as a result of chemical processes. This conversion of chemical energy to electronic energy may serve as a basic link between chemistry and electronics and offers the potential for generation of unique electronic signatures for chemical reactions and the creation of a new class of solid state chemical sensors. Detention of the following chemical species was established: hydrogen, deuterium, carbon monoxide, and molecular oxygen. The detector (1b) consists of a Schottky diode between an Si layer and an ultrathin metal layer with zero force electrical contacts.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: September 25, 2007
    Assignee: Adrena, Inc.
    Inventors: Eric W. McFarland, W. Henry Weinberg, Hermann Nienhaus, Howard S. Bergh, Brian Gergen, Arunava Mujumdar
  • Patent number: 7268407
    Abstract: Provided are a Schottky barrier tunnel single electron transistor and a method of manufacturing the same that use a Schottky barrier formed between metal and semiconductor by replacing a source and a drain with silicide as a reactant of silicon and metal, instead of a conventional method of manufacturing a single electron transistor (SET) that includes source and drain regions by implanting dopants such that an artificial quantum dot is formed in a channel region. As a result, it does not require a conventional PADOX process to form a quantum dot for a single electron transistor (SET), height and width of a tunneling barrier can be artificially adjusted by using silicide materials that have various Schottky junction barriers, and it is possible to improve current driving capability of the single electron transistor (SET).
    Type: Grant
    Filed: August 3, 2005
    Date of Patent: September 11, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Moon Gyu Jang, Yark Yeon Kim, Jae Heon Shin, Seong Jae Lee
  • Patent number: 7247913
    Abstract: A semiconductor device comprises an island shaped channel layer formed on a substrate, the channel later being composed of a semiconductor material, a gate insulation film formed on the channel layer, a gate electrode formed on the gate insulation film, an insulation film formed on both side faces opposite to one direction of the channel layer, a source electrode and a drain electrode made of a metal material and formed on a side face of the insulation layer.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: July 24, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Atsushi Yagishita
  • Patent number: 7190010
    Abstract: A semiconductor device includes a semiconductor substrate, a T-shaped gate electrode, a moisture-proof insulating film, and an interlayer dielectric film. The T-shaped gate electrode has a leg portion joined to the semiconductor substrate and an overhanging head portion spaced from the semiconductor substrate. The T-shaped gate electrode includes a gate metal containing a material reactive with water. The moisture-proof insulating film is located only in the vicinity of the leg portion and covers a side surface of the leg portion of the T-shaped gate electrode. The interlayer dielectric film is located between the overhanging head portion of the T-shaped gate electrode and the semiconductor substrate and has a dielectric constant that is lower than that of the moisture-proof insulating film.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: March 13, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takachika Imato, Hiroshi Matsuoka
  • Patent number: 7105907
    Abstract: A buffer layer, an undoped gallium nitride layer, and an n-type gallium nitride active layer are formed on a sapphire substrate. Ohmic contacts and a Schottky contact are then formed on the n-type gallium nitride active layer as a source contact, a drain contact and a gate contact, respectively. The Schottky contact is a copper alloy, such as palladium copper, in which the content by weight of copper is 5%.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: September 12, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshito Ikeda, Kaoru Inoue, Yutaka Hirose, Katsunori Nishii
  • Patent number: 7092890
    Abstract: A thin GaAs Substrate can be provided with a copper back-metal layer to allow the GaAs Substrate to be packaged using conventional plastic packaging technologies. By providing the GaAs Substrate with a copper back-metal layer, the GaAs Substrate can be made thinner than 2 mils (about 50 microns), thereby reducing heat dissipation problems and allowing the semiconductor die to be compatible with soft-solder technologies. By enabling the semiconductor die to be packaged in a plastic package substantial cost savings can be achieved.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: August 15, 2006
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Alexander J. Elliott, Jeffrey D. Crowder, Monte G. Miller
  • Patent number: 7078782
    Abstract: To attain reduction in size of a semiconductor device having a power transistor and an SBD, a semiconductor device according to the present invention comprises a first region and a second region formed on a main surface of a semiconductor substrate; plural first conductors and plural second conductors formed in the first and second regions respectively; a first semiconductor region and a second semiconductor region formed between adjacent first conductors in the first region, the second semiconductor region lying in the first semiconductor region and having a conductivity type opposite to that of the first semiconductor region; a third semiconductor region formed between adjacent second conductors in the second region, the third semiconductor region having the same conductivity type as that of the second semiconductor region and being lower in density than the second semiconductor region; a metal formed on the semiconductor substrate in the second region, the third semiconductor region having a metal contact
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: July 18, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Nobuyuki Shirai, Nobuyoshi Matsuura, Yoshito Nakazawa
  • Patent number: 7071525
    Abstract: A Merged P-i-N Schottky device in which the oppositely doped diffusions extend to a depth and have been spaced apart such that the device is capable of absorbing a reverse avalanche energy comparable to a Fast Recovery Epitaxial Diode having a comparatively deeper oppositely doped diffusion region.
    Type: Grant
    Filed: January 27, 2004
    Date of Patent: July 4, 2006
    Assignee: International Rectifier Corporation
    Inventors: Davide Chiola, Kohji Andoh, Silvestro Fimiani
  • Patent number: 7071526
    Abstract: A GaN semiconductor device with improved heat resistance of the Schottky junction electrode and excellent power performance and reliability is provided. In this semiconductor device having a Schottky gate electrode 17 which is in contact with an AlGaN electron supplying layer 14, a gate electrode 17 comprises a laminated structure wherein a first metal layer 171 formed of any of Ni, Pt and Pd, a second metal layer 172 formed of any of Mo, Pt, W, Ti, Ta, MoSi, PtSi, WSi, TiSi, TaSi, MoN, WN, TiN and TaN, and a third metal layer formed of any of Au, Cu, Al and Pt. Since the second metal layer comprises a metal material having a high melting point, it works as a barrier to the interdiffusion between the first metal layer and the third metal layer, and the deterioration of the gate characteristics caused by high temperature operation is suppressed.
    Type: Grant
    Filed: June 17, 2003
    Date of Patent: July 4, 2006
    Assignee: NEC Corporation
    Inventors: Yuji Ando, Hironobu Miyamoto, Yasuhiro Okamoto, Kensuke Kasahara, Tatsuo Nakayama, Masaaki Kuzuhara
  • Patent number: 7064408
    Abstract: A power Schottky rectifier device having pluralities of trenches are disclosed. The Schottky barrier rectifier device includes field oxide region having p-doped region formed thereunder to avoid premature of breakdown voltage and having a plurality of trenches formed in between field oxide regions to increase the anode area thereto increase forward current capacity or to shrinkage the planar area for driving the same current capacity. Furthermore, the trenches have rounded corners to alleviate current leakage and LOCOS region in the active region to relief stress during the bonding process. The processes for power Schottky barrier rectifier device including termination region formation need only three masks and thus can gain the benefits of cost down.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: June 20, 2006
    Assignees: Chip Integration Tech Co., Ltd.
    Inventor: Shye-Lin Wu
  • Patent number: 6972470
    Abstract: An embodiment of the invention is a Schottky diode 22 having a semiconductor substrate 3, a first metal 24, a barrier layer 26, and second metal 28. Another embodiment of the invention is a method of manufacturing a Schottky diode 22 that includes providing a semiconductor substrate 3, forming a barrier layer 26 over the semiconductor substrate 3, forming a first metal layer 23 over the semiconductor substrate 3, annealing the semiconductor substrate 3 to form areas 24 of reacted first metal and areas 23 of un-reacted first metal, and removing selected areas 23 of the un-reacted first metal. The method further includes forming a second metal layer 30 over the semiconductor substrate 3 and annealing the semiconductor substrate 3 to form areas 28 of reacted second metal and areas 30 of un-reacted second metal.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: December 6, 2005
    Assignee: Texas Instruments Incorporated
    Inventors: Richard B. Irwin, Tony T. Phan, Hong-Ryong Kim, Ming-Yeh Chuang, Jennifer S. Dumin, Patrick J. Jones, Fredric D. Bailey
  • Patent number: 6969900
    Abstract: A semiconductor diode with hydrogen detection capability includes a semiconductor substrate, a doped semiconductor active layer formed on the substrate and made from a compound having the formula XYZ, in which X is a Group III element, Y is another Group III element different from X, and Z is a Group V element, a semiconductor contact-enhancing layer formed on the active layer and made from a compound having the formula MN, in which M is a Group III element, and N is a Group V element, an ohmic contact layer formed on the semiconductor contact-enhancing layer, and a Schottky barrier contact layer formed on the active layer. The Schottky barrier contact layer is made from a metal that is capable of dissociating a hydrogen molecule into hydrogen atoms.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: November 29, 2005
    Assignee: National Cheng Kung University
    Inventors: Wen-Chau Liu, Huey-Ing Chen, Kun-Wei Lin, Chun-Tsen Lu
  • Patent number: 6963121
    Abstract: A three-terminal semiconductor transistor device comprises a base region formed by a semiconductor material of a first conductivity type at a first concentration, the base region being in contact with a first electrical terminal via a semiconductor material of the second conductivity type at a second concentration, wherein the second concentration is lower than the first concentration. The three-terminal semiconductor transistor device also includes a conductive emitter region in contact with the semiconductor base region, forming a first Schottky barrier junction at the interface of the conductive emitter region and the semiconductor base region. The conductive emitter region is in contact with a second electrical terminal. The three-terminal semiconductor transistor device further includes a conductive collector region in contact with the semiconductor base region, which forms a second Schottky barrier junction at the interface of the conductive collector region and the semiconductor base region.
    Type: Grant
    Filed: February 18, 2004
    Date of Patent: November 8, 2005
    Inventor: Koucheng Wu
  • Patent number: 6956274
    Abstract: A metallization stack is provided for use as a contact structure in an integrated MEMS device. The metallization stack comprises a titanium-tungsten adhesion and barrier layer formed with a platinum layer formed on top. The platinum feature is formed by sputter etching the platinum in argon, followed by a wet etch in aqua regia using an oxide hardmask. Alternatively, the titanium-tungsten and platinum layers are deposited sequentially and patterned by a single plasma etch process with a photoresist mask.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: October 18, 2005
    Assignee: Analog Devices, Inc.
    Inventors: Susan A. Alie, Bruce K. Wachtmann, David S. Kneedler, Scott Limb, Kieran Nunan
  • Patent number: 6949401
    Abstract: A method for producing a semiconductor component with adjacent Schottky (5) and pn (9) junctions positions in a drift area (2, 10) of a semiconductor material. According to the method, a silicon carbide substrate doped with a first doping material of at least 1018 cm?3 is provided, and a silicon carbide layer with a second doping material of the same charge carrier type in the range of 1014 and 1017 cm?3 is homo-epitaxially deposited on the substrate. A third doping material with a complimentary charge carrier is inserted, and structured with the aid of a diffusion and/or ion implantation, on the silicon carbide layer surface that is arranged far from the substrate to form pn junctions. Subsequently the component is subjected to a first temperature treatment between 1400° C. and 1700° C. Following this temperature treatment, a first metal coating is deposited on the implanted surface in order to form a Schottky contact and then a second metal coating is deposited in order to form an ohmic contact.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: September 27, 2005
    Assignee: Daimler Chrysler AG
    Inventors: Nando Kaminski, Raban Held
  • Patent number: 6894360
    Abstract: A filter having a thin-film resonator fabricated on a semiconductor substrate and a method of making the same are disclosed. The filter has a bonding pad connected to the resonator and in contact with the substrate to form a Schottky diode with the substrate to protect the resonator from electrostatic discharges.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: May 17, 2005
    Assignee: Agilent Technologies, Inc.
    Inventor: Paul D. Bradley
  • Patent number: 6870243
    Abstract: A thin GaAs Substrate can be provided with a copper back-metal layer to allow the GaAs Substrate to be packaged using conventional plastic packaging technologies. By providing the GaAs Substrate with a copper back-metal layer, the GaAs Substrate can be made thinner than 2 mils (about 50 microns), thereby reducing heat dissipation problems and allowing the semiconductor die to be compatible with soft-solder technologies. By enabling the semiconductor die to be packaged in a plastic package substantial cost savings can be achieved.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: March 22, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Alexander James Elliott, Jeffrey Dale Crowder, Monte Gene Miller
  • Patent number: 6852615
    Abstract: A process and related product in which ohmic contacts are formed in High Electron Mobility Transistors (HEMTs) employing compound substrates such as gallium nitride. An improved device and an improvement to a process for fabrication of ohmic contacts to GaN/AlGaN HEMTs using a novel two step resist process to fabricate the ohmic contacts are described. This novel two-step process consists of depositing a plurality of layers having compounds of Group III V elements on a substrate; patterning and depositing a first photoresist on one of the layers; etching recessed areas into this layer; depositing ohmic metals on the recessed areas; removing the first photoresist; patterning and depositing a second photoresist, smaller in profile than the first photoresist, on the layer; depositing more ohmic metal on the layer allowing for complete coverage of the recessed areas; removing the second photoresist, and annealing the semiconductor structure.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: February 8, 2005
    Assignee: HRL Laboratories, LLC
    Inventors: Miroslav Micovic, Tahir Hussain, Paul Hashimoto, Janna Ruth Duvall
  • Patent number: 6852578
    Abstract: A high speed, low power Static Random Access Memory (SRAM) Array, which includes a 4T cell with two integrated Schottky Barrier Diodes (SBD) is provided. In a preferred embodiment, the cell bulk area and speed advantage is 30%, and AC power saving is 75% compared with the 6T CFET cell. The physical construct of the 4T cell saves capacitance in all critical nodes intra or inter cell wise, eliminates pass transistors, reduces the well noises. Typical embodiment uses a 0.15-um-rule based layout, and 1.5V supports operation at 5 ns cycles. SBD are used extensively with CFET to form a CMOS version of the Diode Transistor Logic circuitry. Generic control functions can be implemented including NAND/NOR gates, level shifting, decoding, voltage generator, ESD and latch-up protection, leakage control, and dynamic VT setting while in operation. Product applications include DRAM, SRAM, PLD, DRAM, CAM, Flash, Computing, Networking, and Communication devices as standalone system component or embedded into any ASIC.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: February 8, 2005
    Inventor: Augustine Wei-Chun Chang
  • Patent number: 6846729
    Abstract: A Schottky diode is adjusted by implanting an implant species by way of a titanium silicide Schottky contact and driving the implant species into the underlying silicon substrate by a rapid anneal. The implant is at a low energy, (e.g. about 10 keV) and at a low dose (e.g. less than about 9E12 atoms per cm2) such that the barrier height is slightly increased and the leakage current reduced without forming pn junction and retaining the peak boron concentration in the titanium silicide layer.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: January 25, 2005
    Assignee: International Rectifier Corporation
    Inventors: Kohji Andoh, Davide Chiola, Daniel M. Kinzer
  • Patent number: 6838744
    Abstract: A semiconductor device and a manufacturing method therefor are provided, the semiconductor device having a good reverse recovery characteristic, and having no reduction in breakdown voltage because no defect occurs in the upper main surface of a Si substrate even when wires are bonded onto an anode electrode. A semiconductor device includes a Si substrate including an N+ cathode layer and an N? layer. An impurity such as platinum whose barrier height is less than that of silicon is introduced into upper regions of the N? layer where P anode layers are not formed, thereby forming Schottky junction regions. A barrier metal is formed between the Si substrate and an anode electrode.
    Type: Grant
    Filed: October 18, 2002
    Date of Patent: January 4, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hideki Takahashi, Shinji Aono
  • Patent number: 6825105
    Abstract: In the manufacture of trench-gate power MOSFETs, trenched Schottky rectifiers and other devices including a Schottky barrier, a guard region (15s), trenched insulated electrode (11s) and the Schottky barrier (80) are self-aligned with respect to each other by providing spacers (52) to form a narrow window (52a) at a wider window (51a) in a mask pattern (51, 51s) that masks where the Schottky barrier (80) is to be formed. The trenched insulated electrode (11s) is formed by etching a trench (20) at the narrow window (52a) and by providing insulating material (17) and then electrode material (11s) in the trench. The guard region (15s) is provided by introducing dopant (61) via the wider window (51a). The mask pattern (51, 51s) masks the underlying body portion against this dopant introduction and is sufficiently wide (y8) to prevent the dopant (61) from extending laterally into the area where the Schottky barrier (80) is to be formed.
    Type: Grant
    Filed: July 19, 2002
    Date of Patent: November 30, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Raymond J. Grover, Steven T. Peake
  • Publication number: 20040232509
    Abstract: A monolithic three dimensional memory array comprising Schottky diodes components separated by antifuses is disclosed. The Schottky diodes are vertically oriented and disposed on alternating levels. Those on odd levels are “rightside-up” with antifuse over the metal, and those on even levels are “upside down” with metal over the antifuse. Both antifuses are preferably grown oxides.
    Type: Application
    Filed: May 19, 2003
    Publication date: November 25, 2004
    Applicant: MATRIX SEMICONDUCTOR, Inc.
    Inventor: Michael A. Vyvoda
  • Patent number: 6822307
    Abstract: A semiconductor triode comprises a gate electrode provided on a channel layer, wherein there is interposed an insulating metal oxide layer between a top surface of the channel layer and the gate electrode.
    Type: Grant
    Filed: December 26, 2000
    Date of Patent: November 23, 2004
    Assignee: Fujitsu Limited
    Inventors: Mizuhisa Nihei, Yuu Watanabe
  • Publication number: 20040227203
    Abstract: A three-terminal semiconductor transistor device comprises a base region formed by a semiconductor material of a first conductivity type at a first concentration, the base region being in contact with a first electrical terminal via a semiconductor material of the second conductivity type at a second concentration, wherein the second concentration is lower than the first concentration. The three-terminal semiconductor transistor device also includes a conductive emitter region in contact with the semiconductor base region, forming a first Schottky barrier junction at the interface of the conductive emitter region and the semiconductor base region. The conductive emitter region is in contact with a second electrical terminal. The three-terminal semiconductor transistor device further includes a conductive collector region in contact with the semiconductor base region, which forms a second Schottky barrier junction at the interface of the conductive collector region and the semiconductor base region.
    Type: Application
    Filed: February 18, 2004
    Publication date: November 18, 2004
    Inventor: Koucheng Wu
  • Patent number: 6809352
    Abstract: The semiconductor device of the present invention includes: a gallium nitride (GaN) compound semiconductor layer; and a Schottky electrode formed on the GaN compound semiconductor layer, wherein the Schottky electrode contains silicon.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: October 26, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Katsunori Nishii, Yoshito Ikeda, Hiroyuki Masato, Kaoru Inoue
  • Patent number: 6806548
    Abstract: To attain reduction in size of a semiconductor device having a power transistor and an SBD, a semiconductor device according to the present invention comprises a first region and a second region formed on a main surface of a semiconductor substrate; plural first conductors and plural second conductors formed in the first and second regions respectively; a first semiconductor region and a second semiconductor region formed between adjacent first conductors in the first region, the second semiconductor region lying in the first semiconductor region and having a conductivity type opposite to that of the first semiconductor region; a third semiconductor region formed between adjacent second conductors in the second region, the third semiconductor region having the same conductivity type as that of the second semiconductor region and being lower in density than the second semiconductor region; a metal formed on the semiconductor substrate in the second region, the third semiconductor region having a metal contact
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: October 19, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Nobuyuki Shirai, Nobuyoshi Matsuura, Yoshito Nakazawa