Schottky Barrier Patents (Class 257/471)
  • Patent number: 6855998
    Abstract: A semiconductor device comprises a field effect transistor and a schottky-barrier diode mounted in the same semiconductor substrate, the semiconductor device having buried doped layers buried at a predetermined interval in a drift layer of a first conductivity type in a schottky-barrier diode region so as to have a predetermined depth, the buried doped layers having a second conductivity type.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: February 15, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoshitaka Hokomoto
  • Patent number: 6855983
    Abstract: A trench gate type semiconductor device has an ON resistance that has been reduced. The device has a drain electrode on one side of the substrate and has a drift region, channel region, source region, and a source electrode on the other side. The channel region is sandwiched between a trench gate region covered with insulating film. Current passes when a positive bias voltage is applied to the trench region, and current is cut off when a negative bias voltage is applied.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: February 15, 2005
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Tomoyoshi Kushida
  • 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
  • Publication number: 20040256690
    Abstract: In accordance with an embodiment of the invention, a Schottky diode includes a metal layer in contact with a semiconductor region to form a Schottky barrier therebetween. A first trench extends in the semiconductor region. The first trench includes at least one electrode or diode therein.
    Type: Application
    Filed: April 9, 2004
    Publication date: December 23, 2004
    Inventor: Christopher Boguslaw Kocon
  • Publication number: 20040245594
    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 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: Application
    Filed: May 14, 2004
    Publication date: December 9, 2004
    Applicant: Adrena, Inc.
    Inventors: Eric W. McFarland, Henry W. Weinberg, Hermann Nienhaus, Howard S. Bergh, Brian Gergen, Arunava Mujumdar
  • 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: 20040183153
    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: Application
    Filed: March 10, 2004
    Publication date: September 23, 2004
    Inventors: Wen-Chau Liu, Huey-Ing Chen, Kun-Wei Lin, Chun-Tsen Lu
  • Publication number: 20040178468
    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 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: Application
    Filed: September 2, 2003
    Publication date: September 16, 2004
    Applicant: Adrena, Inc,
    Inventors: Eric W. McFarland, Henry W. Weinberg, Hermann Nienhaus, Howard S. Bergh, Brian Gergen, Arunava Mujumdar
  • Patent number: 6791154
    Abstract: An integrated semiconductor circuit device comprising a diode bridge circuit formed of a Schottky barrier diode and a periphery circuit formed of a MOS transistor which are formed on a single silicon substrate, wherein a Schottky barrier, which is a component of the Schottky barrier diode, is made of a silicide layer.
    Type: Grant
    Filed: January 25, 2002
    Date of Patent: September 14, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hironori Matsumoto, Toshinori Ohmi
  • Patent number: 6787871
    Abstract: An integrated Schottky barrier diode chip includes a compound semiconductor substrate, a plurality of Schottky barrier diodes formed on the substrate and an insulating region formed on the substrate by an on implantation. The insulating region electrically separates a portion of a diode at a cathode voltage from a portion of the diode at an anode voltage. Because of the absence of a polyimide layer and trench structures, this planar device configuration results in simpler manufacturing method and improved device characteristics.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: September 7, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onoda, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Patent number: 6784489
    Abstract: A method of operating a vertical DMOS transistor associated with a Schottky diode, the method including diverting current from flowing through a body-to-drain pn junction diode to flowing through the Schottky diode when a metallic source contact becomes more positive than a drain of the DMOS transistor by forward conduction voltage of the Schottky diode to reduce the amount of source current reaching the substrate and reducing operational characteristics of parasitic devices associated with the integrated circuit.
    Type: Grant
    Filed: September 12, 2000
    Date of Patent: August 31, 2004
    Assignee: STMicroelectronics, Inc.
    Inventor: Paolo Menegoli
  • Patent number: 6774451
    Abstract: This invention relates to a MOS transistor made in the thin film of silicon of an SOI chip (10), said thin film (13) being slightly doped and of less than 30 nm in thickness, the source (14) and drain (15) contacts being of the Schottky type at the lowest level of Schottky barrier possible for majority carriers, with an accumulation type transistor operation.
    Type: Grant
    Filed: January 6, 2003
    Date of Patent: August 10, 2004
    Assignee: Centre National de la Recherche Scientifique
    Inventor: Emmanuel Dubois
  • Patent number: 6768138
    Abstract: The invention relates to technology improving the withstand voltage of a Schottky diode. With a diode of the present invention, the distance a between the long sides of the narrow groove withstand voltage portions and the inner ring circumference of the intermediate withstand voltage portion is set to twice the distance b between the short sides of the narrow groove withstand voltage portions and the inner ring circumference of the intermediate withstand voltage portion. Furthermore, the distance c between the inner ring circumference of the innermost outer withstand voltage portions and the outer ring circumference of the intermediate withstand voltage portion, the distance u between the adjacent outer withstand voltage portions, and the distance d between the adjacent narrow groove withstand voltage portions are all equal to the distance a.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: July 27, 2004
    Assignee: Shindengen Electric Manufacturing Co., Ltd.
    Inventors: Mizue Kitada, Kosuke Ohsima, Shinji Kunori
  • Publication number: 20040129994
    Abstract: Disclosed is a semiconductor radiation detector element of Schottky barrier type, comprising: a compound semiconductor crystal including cadmium and tellurium as main components; and voltage application means for applying voltage to the compound semiconductor crystal. According to the present invention, said voltage application means includes a compound of indium, cadmium and tellurium: InxCdyTez formed on one surface of the compound semiconductor crystal. Preferably, the rate “z” of occupation of tellurium in the compound InxCdyTez is in the range of not less than 42.9%, but not greater than 50% by ratio of number of atoms. Furthermore, preferably, the rate “y” of occupation of cadmium in the compound InxCdyTez is in the range of not less than 0%, but not greater than 10% by ratio of number of atoms.
    Type: Application
    Filed: October 29, 2003
    Publication date: July 8, 2004
    Applicant: Acrorad Co., Ltd.
    Inventors: Miki Moriyama, Masaki Murakami, Atsushi Kyan, Ryoichi Ohno
  • Publication number: 20040129993
    Abstract: A Semiconductor component, such as an IGBT, a thyristor, a GTO or a diode, and especially a Schottky diode is provided that is capable of blocking for producing a termination portion of a semiconductor component. An insulator profile of an insulator portion includes a curved surface, which is free of steps and is produced by gray-tone lithography in the termination portion of an anode. The device also includes a substrate that is covered with an insulating layer having a thickness of between 0.5 &mgr;m and 15 &mgr;m, an insulator layer having a thickness is covered with a photosensitive layer (photoresist layer) where the photoresist layer is exposed through a mask, which changes in its gray-tone value in accordance with the course of curvature of the surface of at least one insulator profile, and is subsequently structured to form at least one resist remainder.
    Type: Application
    Filed: September 23, 2003
    Publication date: July 8, 2004
    Inventors: Roland Sittig, Detlef Nagel, Ralf-Ulrich Dudde, Bernd Wagner, Klaus Reimer
  • Publication number: 20040119131
    Abstract: The invention described herein relates to physical vapor deposition targets comprising both Ti and Zr. The targets can comprise a uniform texture across the target surface and throughout the thickness; and can further have an increased mechanical strength compared to high purity titanium and tantalum. The sputtering targets can be utilized to sputter deposit a thin film; and such film can be utilized as a copper barrier layer.
    Type: Application
    Filed: November 12, 2002
    Publication date: June 24, 2004
    Inventor: Stephen P. Turner
  • Patent number: 6753588
    Abstract: A semiconductor rectifier includes an intermediate semiconductor region (29) extending between anode (9) and cathode (7) contacts. A trenched gate (19) with insulated sidewalls (15) and base (17) can deplete the intermediate region. However, a shield region (23) acts to shield the intermediate region (29) from the gate (19) to allow current to flow in dependence on the polarity of the voltage applied between anode and cathode contacts (9, 7).
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: June 22, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Eddie Huang, Steven T. Peake
  • Patent number: 6753580
    Abstract: A diode is formed having a weak injection shallow, low P concentration anode in an N type wafer or die. The resulting diode has a soft reverse recovery characteristic with low recovery voltage and is particularly useful either as a power factor correction diode or as an antiparallel connected diode in a motor control circuit.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: June 22, 2004
    Assignee: International Rectifier Corporation
    Inventors: Richard Francis, Chiu Ng, Fabrizio Ruo Redda
  • Patent number: 6744111
    Abstract: A three-terminal semiconductor transistor device comprises a semiconductor base region in contact with a first electric terminal, 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 electric terminal. The three-terminal semiconductor transistor device further includes a conductive collector region in contact with the semiconductor base region, forming a second Schottky barrier junction at the interface of the conductive collector region and the semiconductor base region. The conductive collector region is in contact with a third electric terminal. The tunneling currents through the first and the second Schottky barrier junctions are substantially controlled by the voltage of the semiconductor base region.
    Type: Grant
    Filed: May 15, 2003
    Date of Patent: June 1, 2004
    Inventor: Koucheng Wu
  • Publication number: 20040089908
    Abstract: A Schottky diode is fabricated by a sequence of fabrication by a sequence of fabrication steps. An active region of a semiconductor substrate is defined in which a Schottky diode is fabricated. At least first and second layers of insulating material are applied over the active area. A first layer of insulating material, having a first etching rate, is applied over the active area. A second layer of insulating material having a second, greater, etch rate is applied over the first layer of insulating material to a thickness that is about twice the thickness of the first layer of insulating material. The insulating material is patterned and a window is etched through the layers of insulating material to the semiconductor substrate. Metal is applied and unwanted metal is etched away leaving metal in the window forming a Schottky contact therein. One or more barrier layers may be employed.
    Type: Application
    Filed: October 29, 2003
    Publication date: May 13, 2004
    Inventors: John Charles Desko, Michael J. Evans, Chung-Ming Hsieh, Tzu-Yen Hsieh, Bailey R. Jones, Thomas J. Krutsick, John Michael Siket, Brian Eric Thompson, Steven W. Wallace
  • Patent number: 6734515
    Abstract: A semiconductor light receiving element having a light receiving layer (1) formed from a GaN group semiconductor, and an electrode (2) formed on one surface of the light receiving layer as a light receiving surface (1a) in such a way that the light (L) can enter the light receiving layer is provided. When the light receiving element is of a Schottky barrier type, the aforementioned electrode (2) contains at least a Schottky electrode, which is formed in such a way that, on the light receiving surface (1a), the total length of the boundary lines between areas covered with the Schottky electrode and exposed areas is longer than the length of the outer periphery of the light receiving surface (1a).
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: May 11, 2004
    Assignees: Mitsubishi Cable Industries, Ltd., Nikon Corporation
    Inventors: Kazuyuki Tadatomo, Hiroaki Okagawa, Youichiro Ohuchi, Masahiro Koto, Kazumasa Hiramatsu, Yutaka Hamamura, Sumito Shimizu
  • Publication number: 20040080010
    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: Application
    Filed: May 20, 2003
    Publication date: April 29, 2004
    Applicant: Cree Lighting Company
    Inventors: Primit Parikh, Umesh Mishra
  • Publication number: 20040061194
    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: Application
    Filed: June 3, 2003
    Publication date: April 1, 2004
    Inventors: Yoshito Ikeda, Kaoru Inoue, Yutaka Hirose, Katsunori Nishii
  • Patent number: 6710418
    Abstract: In accordance with an embodiment of the present invention, a semiconductor rectifier includes an insulation-filled trench formed in a semiconductor region. Strips of resistive material extend along the trench sidewalls. The strips of resistive material have a conductivity type opposite that of the semiconductor region. A conductor extends over and in contact with the semiconductor region so that the conductor and the underlying semiconductor region form a Schottky contact.
    Type: Grant
    Filed: October 11, 2002
    Date of Patent: March 23, 2004
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Steven P. Sapp
  • Patent number: 6707127
    Abstract: A Schottky rectifier is provided. The Schottky rectifier comprises: (a) a semiconductor region having first and second opposing faces, with the semiconductor region comprising a cathode region of first conductivity type adjacent the first face and a drift region of the first conductivity type adjacent the second face, and with the drift region having a lower net doping concentration than that of the cathode region; (b) one or more trenches extending from the second face into the semiconductor region and defining one or more mesas within the semiconductor region; (c) an insulating region adjacent the semiconductor region in lower portions of the trench; (d) and an anode electrode that is (i) adjacent to and forms a Schottky rectifying contact with the semiconductor at the second face, (ii) adjacent to and forms a Schottky rectifying contact with the semiconductor region within upper portions of the trench and (iii) adjacent to the insulating region within the lower portions of the trench.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: March 16, 2004
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Max Chen, Koon Chong So, Yan Man Tsui
  • Publication number: 20040046224
    Abstract: The invention concerns a Schottky-diode semiconductor device, comprising a substrate consisting of first (2) and second (3) semiconductor layers having the same type of conduction tiered up in said substrate, the second layer (3) being more highly doped than the first (2), said substrate having first (4) and second (5) main surfaces in contact with first (8) and second (6) electrodes, a Schottky barrier being formed between the first electrode (8) and said first layer. The invention is characterised in that the plurality of islands (9) having a type of conduction opposite to that of the first layer (2) are arranged in beds spaced apart in the thickness of said layer (2).
    Type: Application
    Filed: March 20, 2003
    Publication date: March 11, 2004
    Inventors: Pierre Rossel, Frederic Morancho, Nathalie Cezac, Henri Tranduc
  • Patent number: 6703678
    Abstract: A Schottky barrier field effect transistor has a gate electrode formed with a field plate in order to achieve a high withstanding voltage, where the thickness of the dielectric layer between the channel layer and the field plate, the distance between the Schottky contact and the drain and the length of the field plate falls within the range of 300 nanometers to 600 nanometers thick, the range from 800 nanometers to 3000 nanometers long and the range of the distance between the Schottky contact and the drain is plus or minus 400 nanometers, respectively, so that the distortion and the return-loss are improved without sacrifice of the withstanding voltage.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: March 9, 2004
    Assignee: NEC Compound Semiconductor Devices, Ltd.
    Inventors: Tomoaki Hirokawa, Zenzou Shingu, Shigeru Saitou
  • Publication number: 20040041226
    Abstract: A CMOS device and method of fabrication are disclosed. The present invention utilizes Schottky barrier contacts for source and/or drain contact fabrication within the context of a CMOS device and CMOS integrated circuits, to eliminate the requirement for halo/pocket implants, shallow source/drain extensions to control short channel effects, well implant steps, and complex device isolation steps. Additionally, the present invention eliminates the parasitic bipolar gain associated with CMOS device operation, reduces manufacturing costs, tightens control of device performance parameters, and provides for superior device characteristics as compared to the prior art. The present invention, in one embodiment, uses a silicide exclusion mask process to form the dual silicide Schottky barrier source and/or drain contact for the complimentary PMOS and NMOS devices forming the CMOS device.
    Type: Application
    Filed: May 16, 2003
    Publication date: March 4, 2004
    Inventors: John P. Snyder, John M. Larson
  • Patent number: 6683362
    Abstract: The subject invention relates to a metal-semiconductor diode clamped semiconductor device and method for producing such device. A specific embodiment of the subject invention utilizes one or more Schottky barriers at, for example, the drain and/or source of at least one transistor of a field effect transistor integrated circuit. The use of one or more Schottky barriers is useful for reducing the susceptibility of latch-up for circuits having two opposite type transistors, i.e., two opposite polarity carriers, in which the two transistors are in close enough proximity to experience latch-up. This can allow the spacing between n- and p-type transistors to be reduced, thus reducing the area of the circuit. The subject invention can also allow the elimination of a metal contact by utilizing the metal layer used to form the metal-semiconductor junction in a complementary IGFET structure, to further reduce the circuit area. The subject invention is applicable to complementary metal oxide silicon (CMOS) devices.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: January 27, 2004
    Inventors: Kenneth K. O, Feng-Jung Huang
  • Publication number: 20040012066
    Abstract: A Schottky diode has a Schottky junction formed by a thin metal layer and/or metal silicide layer at the top side of a doped well in a semiconductor body or substrate. In contrast to the fabrication of low-impedance contacts on CMOS wells, a metal, to be precise titanium in the preferred embodiment, is applied not to a highly doped contact region but to the lightly doped semiconductor material of the doped well, for example an HV well for the fabrication of high-voltage transistors.
    Type: Application
    Filed: July 11, 2003
    Publication date: January 22, 2004
    Inventors: Josef Dietl, Hans Taddiken
  • Publication number: 20040007723
    Abstract: A fabrication process for a Schottky barrier structure includes forming a nitride layer directly on a surface of an epitaxial (“epi”) layer and subsequently forming a plurality of trenches in the epi layer. The interior walls of the trenches are then deposited with a final oxide layer without forming a sacrificial oxide layer to avoid formation of a beak bird at the tops of the interior trench walls. A termination trench is etched in the same process step for forming the plurality of trenches in the active area.
    Type: Application
    Filed: July 11, 2002
    Publication date: January 15, 2004
    Applicant: International Rectifier Corp.
    Inventors: Kohji Andoh, Davide Chiola
  • Patent number: 6674099
    Abstract: A metal insulator semiconductor field effect transistor (MISFET) is disclosed comprising a source layer being made with a material having a source band-gap (EG2) and a source mid-gap value (EGM2), the source layer having a source Fermi-Level (EF2). A drain layer has a drain Fermi-Level (EF4). A channel layer is provided between the source layer and the drain layer, the channel layer being made with a material having a channel band-gap (EG3) and a channel mid-gap value (EGM3), the channel layer having a channel Fermi-Level (EF3). A source contact layer is connected to the source layer opposite the channel layer, the source contact layer having a source contact Fermi-Level (EF1). A gate electrode has a gate electrode Fermi-Level (EF6). The source band-gap is substantially narrower (EG2) than the channel band-gap (EG3).
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: January 6, 2004
    Assignee: Quantum Semiconductor, LLC
    Inventor: Carlos J. R. P. Augusto
  • Patent number: 6674130
    Abstract: A new type of partially-depleted SOI MOSFET is described in which a tunneling connection between the gate and the base is introduced. This is achieved by using a gate dielectric whose thickness is below its tunneling threshold. The gate pedestal is made somewhat longer than normal and a region near one end is implanted to be P+ (or N+ in a PMOS device). This allows holes (electrons for PMOS) to tunnel from gate to base. Since the hole current is self limiting, applied voltages greater than 0.7 volts may be used without incurring excessive leakage (as is the case with prior art DTMOS devices). A process for manufacturing the device is also described.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: January 6, 2004
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Kuo-Nan Yang, Yi-Ling Chan, You-Lin Chu, Hou-Yu Chen, Fu-Liang Yang, Chenming Hu
  • Patent number: 6670650
    Abstract: A high-speed, soft-recovery semiconductor device that reduces leakage current by increasing the Schottky ratio of Schottky contacts to pn junctions. In one embodiment of the present invention, an n− drift layer is formed on an n+ cathode layer 1 by epitaxial growth, and ring-shaped ring trenches having a prescribed width are formed in the n− drift layer. Oxide films are formed on the side walls of each ring trench. The ring trenches are arranged such that the centers of the rings of the ring trenches adjacent to one another form a triangular lattice unit. A p− anode layer is formed at the bottom of each ring trench. Schottky contacts are formed at the interface between an anode electrode and the surface of the n− drift layer. Ohmic contact is established between the surfaces of polysilicon portions and the anode electrode.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: December 30, 2003
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Michio Nemoto, Tatsuya Naito, Masahito Otsuki, Mitsuaki Kirisawa
  • Patent number: 6670688
    Abstract: A semiconductor device which can prevent an operation thereof from being uncontrollable to obtain a high reliability, and can be manufactured easily and can reduce a manufacturing cost. A p-type impurity layer containing a p-type impurity in a relatively high concentration is provided as an operation region of a diode in one of main surfaces of a silicon substrate containing an n-type impurity in a relatively low concentration and a plurality of ring-shaped Schottky metal layers are concentrically provided on the main surface of the silicon substrate around the p-type impurity layer with a space formed therebetween to surround the p-type impurity layer. A silicon oxide film is provided on the main surface of the silicon substrate around the p-type impurity layer and an anode electrode is provided on the p-type impurity layer.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: December 30, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Katsumi Satoh, Eisuke Suekawa
  • Patent number: 6670687
    Abstract: A semiconductor device having a silicon carbide layer of a singular conductivity type. The silicon carbide layer includes a surface having a first region, a second region, and a third region sandwiched between the first region and the second region. An anode electrode having a Schottky contact with the first region, a cathode electrode having an ohmic contact with the second region, and a control electrode having a Schottky contact with the third region are included in the semiconductor device.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: December 30, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Katsumi Satoh, Shinichi Ishizawa
  • Patent number: 6657273
    Abstract: A composite field ring for a Schottky diode has a low concentration deep portion to increase breakdown voltage withstand and a high concentration, shallow region to enable minority carrier injection during high forward current conduction. The composite ring permits a reduction in the thickness of the epitaxially formed layer which receives the Schottky barrier metal.
    Type: Grant
    Filed: June 12, 2002
    Date of Patent: December 2, 2003
    Assignee: International Rectifirer Corporation
    Inventor: Slawomir Skocki
  • Publication number: 20030218230
    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 comprises a Si substrate including an N+ cathode layer (101) and an N− layer (102). An impurity such as platinum whose barrier height is less than that of silicon is introduced into upper regions of the N− layer (102) where P anode layers (103) are not formed, thereby forming Schottky junction regions (104). A barrier metal (105) is formed between the Si substrate and an anode electrode (106).
    Type: Application
    Filed: October 18, 2002
    Publication date: November 27, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Hideki Takahashi, Shinji Aono
  • Publication number: 20030193074
    Abstract: A Schottky rectifier is provided. The Schottky rectifier comprises: (a) a semiconductor region having first and second opposing faces, with the semiconductor region comprising a cathode region of first conductivity type adjacent the first face and a drift region of the first conductivity type adjacent the second face, and with the drift region having a lower net doping concentration than that of the cathode region; (b) one or more trenches extending from the second face into the semiconductor region and defining one or more mesas within the semiconductor region; (c) an insulating region adjacent the semiconductor region in lower portions of the trench; (d) and an anode electrode that is (i) adjacent to and forms a Schottky rectifying contact with the semiconductor at the second face, (ii) adjacent to and forms a Schottky rectifying contact with the semiconductor region within upper portions of the trench and (iii) adjacent to the insulating region within the lower portions of the trench.
    Type: Application
    Filed: May 5, 2003
    Publication date: October 16, 2003
    Inventors: Fwu-luan Hshieh, Koon Chong So
  • Patent number: 6627970
    Abstract: An integrated semiconductor circuit, in particular a semiconductor memory circuit, having at least one integrated electrical antifuse structure is described. The antifuse structure is located within an insulated well composed of semiconductor material.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: September 30, 2003
    Assignee: Infineon Technologies AG
    Inventors: Robert Fuller, Helmut Schneider
  • Patent number: 6624493
    Abstract: Disclosed are semiconductor devices including at least one junction which is rectifying whether the semiconductor is caused to be N or P-type, by the presence of applied gate voltage field induced carriers in essentially intrinsic, essentially homogeneously simultaneously containing both N and P-type metallurgical dopants at substantially equal doping levels, essentially homogeneously simultaneously containing both N and P-type metallurgical dopants at different doping levels, and containing a single metallurgical doping type, and functional combinations thereof. In particular, inverting and non-inverting gate voltage channel induced semiconductor single devices with operating characteristics similar to conventional multiple device CMOS systems, which can be operated as modulators, are disclosed as are a non-latching SCR and an approach to blocking parasitic currents utilizing material(s) which form rectifying junctions with both N and P-type semiconductor whether metallurigically or field induced.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: September 23, 2003
    Inventor: James D. Welch
  • Patent number: 6617642
    Abstract: The field effect transistor of the present invention includes a body diffusion region having a source diffusion region therein. The field effect transistor further includes a metal source contact adjacent the body diffusion region and the source diffusion region. The metal source contact forms a Schottky type contact with the body diffusion region.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: September 9, 2003
    Assignee: Tripath Technology, Inc.
    Inventor: Sorin Stefan Georgescu
  • Patent number: 6610999
    Abstract: A Schottky rectifier has multiple stages with substantially identical or very similar structures. Each stage includes a nitride-based semiconductor layer, a Schottky contact formed on one surface of the semiconductor layer, and an ohmic contact formed on an opposite surface of the semiconductor layer. The Schottky layer is formed from a metallic material with a high metal work function, and the ohmic contact is formed from a metallic material with a low metal work function. At least one of the stages is a middle stage located between two adjacent stages, such that the Schottky contact of the middle stage and the ohmic contact of one of the adjacent stages are joined together, and such that the ohmic contact of the middle stage and the Schottky contact of another one of the adjacent stages are joined together.
    Type: Grant
    Filed: May 8, 2001
    Date of Patent: August 26, 2003
    Assignee: California Institute of Technology
    Inventors: Zvonimir Z. Bandic, Eric C. Piquette, Thomas C. McGill
  • Patent number: 6608362
    Abstract: A method of fabricating high quality passive components having reduced capacitive and magnetic effects by using a Schottky diode underlying the passive components in the manufacture of integrated circuits is described. A Schottky diode is formed completely covering an active area where passive devices are to be formed. The Schottky diode is covered with a dielectric layer. Passive components are formed overlying the dielectric layer wherein the Schottky diode reduces substrate noise resulting in high quality of the passive components.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: August 19, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Shao Kai, Sanford Chu, Chit Hwei Ng, Jia Zhen Zheng, Sia Choon Beng, Chew Kok Wai
  • Publication number: 20030132496
    Abstract: On an In-containing compound semiconductor are sequentially formed Zn (p-type dopant-containing layer), Ta (high-melting metal layer) and a low-resistance conductor layer in this order as a Schottky electrode, and the resulting assemblage is annealed to diffuse Zn into the semiconductor to thereby convert the surface of the semiconductor layer only in a region in contact with the Schottky electrode metal into a p-type layer. The p-type dopant-containing layer can be, instead of Zn, a compound between Zn and an element constituting the In-containing compound semiconductor or a Zn—Ta alloy. The high-melting metal layer can be, instead of Ta, an intermetallic compound between Ta and an element constituting the In-containing compound semiconductor or a Zn—Ta alloy.
    Type: Application
    Filed: November 19, 2002
    Publication date: July 17, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Akihisa Terano, Hiroshi Ohta, Kiyoshi Ouchi, Tomoyoshi Mishima
  • Publication number: 20030129813
    Abstract: In the present invention, there is provided semiconductor devices such as a Schottky UV photodetector fabricated on n-type ZnO and MgxZn1-xO epitaxial films. The ZnO and MgxZn1-xO films are grown on R-plane sapphire substrates and the Schottky diodes are fabricated on the ZnO and MgxZn1-xO films using silver and aluminum as Schottky and ohmic contact metals, respectively. The Schottky diodes have circular patterns, where the inner circle is the Schottky contact, and the outside ring is the ohmic contact. Ag Schottky contact patterns are fabricated using standard liftoff techniques, while the Al ohmic contact patterns are formed using wet chemical etching. These detectors show low frequency photoresponsivity, high speed photoresponse, lower leakage current and low noise performance as compared to their photoconductive counterparts. This invention is also applicable to optical modulators, Metal Semiconductor Field Effect Transistors (MESFETs) and more.
    Type: Application
    Filed: May 30, 2002
    Publication date: July 10, 2003
    Applicant: Rutgers, The State University Of New Jersey
    Inventors: Yicheng Lu, Haifeng Sheng, Sriram Muthukumar, Nuri William Emanetoglu, Jian Zhong
  • Patent number: 6586813
    Abstract: A compound semiconductor device includes a cap layer formed on a channel layer and an insulating film formed on the cap layer, and a &Ggr;-shaped gate electrode is provided in a gate recess opening, wherein an extension part of the &Ggr;-shaped gate electrode extends over the insulating film toward a drain electrode, and the total thickness of the insulating film and the cap layer being is set such that the electric field formed right underneath the extension part of the gate electrode includes a component acting in a direction perpendicular to the substrate.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: July 1, 2003
    Assignee: Fujitsu Quantum Devices Limited
    Inventor: Masaki Nagahara
  • Patent number: 6583485
    Abstract: The invention relates to a semiconductor device, in particular a Schottky hybrid diode with a guard ring (S). The semiconductor device comprises a semiconductor substrate (1), an epitaxial layer (2) on which an insulating layer (3) with an opening (10) is deposited, with a Schottky metal layer (9) covering the epitaxial layer (2) lying at the bottom of the opening (10), and with an annular semiconductor region (4) which is present in the epitaxial layer (2). A doping region (6) is present in the epitaxial layer (2) along the outer contour of the semiconductor device, and in addition an oxide layer (8) is present on the epitaxial layer (2).
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: June 24, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Thomas Epke
  • Patent number: 6580141
    Abstract: A Schottky rectifier is provided. The Schottky rectifier comprises: (a) a semiconductor region having first and second opposing faces, with the semiconductor region comprising a cathode region of first conductivity type adjacent the first face and a drift region of the first conductivity type adjacent the second face, and with the drift region having a lower net doping concentration than that of the cathode region; (b) one or more trenches extending from the second face into the semiconductor region and defining one or more mesas within the semiconductor region; (c) an insulating region adjacent the semiconductor region in lower portions of the trench; (d) and an anode electrode that is (i) adjacent to and forms a Schottky rectifying contact with the semiconductor at the second face, (ii) adjacent to and forms a Schottky rectifying contact with the semiconductor region within upper portions of the trench and (iii) adjacent to the insulating region within the lower portions of the trench.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: June 17, 2003
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Koon Chong So
  • Publication number: 20030089959
    Abstract: A Schottky barrier diode has a Schottky contact region formed in an n epitaxial layer disposed on a GaAs substrate and an ohmic electrode surrounding the Schottky contact region. The ohmic electrode is disposed directly on an impurity-implanted region formed on the substrate. An insulating region is formed through the n epitaxial layer so that an anode bonding pad is isolated form other elements of the device at a cathode voltage. The planar configuration of this device does not include the conventional polyimide layer, and thus has a better high frequency characteristics than conventional devices.
    Type: Application
    Filed: July 26, 2002
    Publication date: May 15, 2003
    Applicant: Sanyo Electric Company, Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onada, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara