Into Grooved Or Recessed Semiconductor Region Patents (Class 438/576)
  • Patent number: 8105888
    Abstract: A diode assembly comprising first and second diodes each having a different breakdown voltage, each of the first and second diodes comprising a semiconductor substrate; an electrically conducting channel layer on the semiconductor substrate; an upper semiconductor layer on the channel layer, the upper semiconductor layer comprising a recess; first and second ohmic contacts on the upper semiconductor layer on opposite sides of the recess, the ohmic contacts being connected together to form a first diode contact; a gate electrode within the recess, the gate electrode forming a second diode contact; wherein the area of the recess of the first diode covered by the first gate electrode is different to the area of the recess of the second diode covered by the second gate electrode.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: January 31, 2012
    Assignee: RFMD (UK) Limited
    Inventor: John Stephen Atherton
  • Patent number: 8049251
    Abstract: In a semiconductor film having a heterojunction structure, for example a semiconductor film (11) including a SiGe layer (2) and a Si layer (3) formed on the SiGe layer (2), impurity concentration is controlled in such a manner that the concentration of impurity in the lower, SiGe layer (2) becomes higher than that in the upper, Si layer (3) by exploiting the fact that there is a difference between the SiGe layer (2) and the Si layer (3) in the diffusion coefficient of the impurity. The impurity contained in the semiconductor film 11 is of the conductivity type opposite to that of the transistor (p-type in the case of an n-type MOS transistor whereas n-type in the case of a p-type MOS transistor). In this way, the mobility in a semiconductor device including a semiconductor film having a heterojunction structure with a compression strain structure is increased, thereby improving the transistor characteristics and reliability of the device.
    Type: Grant
    Filed: September 14, 2006
    Date of Patent: November 1, 2011
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Masashi Shima
  • Patent number: 8048789
    Abstract: Ordered, two-dimensional arrays of pyramidal particulates and related methods of preparation.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: November 1, 2011
    Assignee: Northwestern University
    Inventors: Teri W. Odom, Joel Henzie, Eun-Soo Kwak
  • Publication number: 20110215338
    Abstract: An electronic device includes a silicon carbide layer including an n-type drift region therein, a contact forming a junction, such as a Schottky junction, with the drift region, and a p-type junction barrier region on the silicon carbide layer. The p-type junction barrier region includes a p-type polysilicon region forming a P-N heterojunction with the drift region, and the p-type junction barrier region is electrically connected to the contact. Related methods are also disclosed.
    Type: Application
    Filed: March 8, 2010
    Publication date: September 8, 2011
    Inventor: Qingchun Zhang
  • Patent number: 8003459
    Abstract: A method for forming different active thicknesses on the same silicon layer includes masking the silicon layer and exposing selected regions of the silicon layer. The thickness of the silicon layer at the exposed regions is changed, either by adding silicon or subtracting silicon from the layer at the exposed regions. Once the mask is removed, the silicon layer has regions of different active thicknesses, respectively suitable for use in different types of devices, such as diodes and transistors.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: August 23, 2011
    Assignee: Advanced Micro Devices, Inc.
    Inventors: David E. Brown, Hans Van Meer, Sey-Ping Sun
  • Publication number: 20110156051
    Abstract: Embodiments include semiconductor devices with low leakage Schottky contacts. An embodiment is formed by providing a partially completed semiconductor device including a substrate, a semiconductor on the substrate, and a passivation layer on the semiconductor, and using a first mask, locally etching the passivation layer to expose a portion of the semiconductor. Without removing the first mask, a Schottky contact is formed of a first material on the exposed portion of the semiconductor, and the first mask is removed. Using a further mask, a step-gate conductor of a second material electrically coupled to the Schottky contact is formed overlying parts of the passivation layer adjacent to the Schottky contact. By minimizing the process steps between opening the Schottky contact window in the passivation layer and forming the Schottky contact material in this window, the gate leakage of a resulting field effect device having a Schottky gate may be substantially reduced.
    Type: Application
    Filed: March 8, 2011
    Publication date: June 30, 2011
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Bruce M. Green, Haldane S. Henry, Chun-Li Liu, Karen E. Moore, Matthias Passlack
  • Patent number: 7947606
    Abstract: Methods of forming features and structures thereof are disclosed. In one embodiment, a method of forming a feature includes forming a first material over a workpiece, forming a first pattern for a lower portion of the feature in the first material, and filling the first pattern with a sacrificial material. A second material is formed over the first material and the sacrificial material, and a second pattern for an upper portion of the feature is formed in the second material. The sacrificial material is removed. The first pattern and the second pattern are filled with a third material.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: May 24, 2011
    Assignee: Infineon Technologies AG
    Inventors: Jiang Yan, Roland Hampp, Jin-Ping Han, Manfred Eller, Alois Gutmann
  • Patent number: 7923753
    Abstract: The contact resistance between an Ohmic electrode and an electron transit layer is reduced compared with a case in which the Ohmic electrode is provided to a depth less than the heterointerface. As a result, for an Ohmic electrode provided in a structure comprising an electron transit layer formed of a first semiconductor layer formed on a substrate, an electron supply layer comprising a second semiconductor layer forming a heterojunction with the electron transit layer and having a smaller electron affinity than the first semiconductor layer, and a two-dimensional electron layer induced in the electron transit layer in the vicinity of the heterointerface, the end portion of the Ohmic electrode is positioned in the electron transit layer in penetration into the electron supply layer at a depth equal to or greater than the heterointerface.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: April 12, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Juro Mita, Katsuaki Kaifu
  • Patent number: 7923362
    Abstract: A method for manufacturing a metal-semiconductor contact in semiconductor Components is disclosed. There is a relatively high risk of contamination in the course of metal depositions in prior-art methods. In the disclosed method, the actual metal -semiconductor or Schottky contact is produced only after the application of a protective layer system, as a result of which it is possible to use any metals, particularly platinum, without the risk of contamination.
    Type: Grant
    Filed: June 6, 2006
    Date of Patent: April 12, 2011
    Assignee: TELEFUNKEN Semiconductors GmbH & Co. KG
    Inventors: Franz Dietz, Volker Dudek, Tobias Florian, Michael Graf
  • Publication number: 20100327288
    Abstract: A trench Schottky diode and its manufacturing method are provided. The trench Schottky diode includes a semiconductor substrate having therein a plurality of trenches, a gate oxide layer, a polysilicon structure, a guard ring and an electrode. At first, the trenches are formed in the semiconductor substrate by an etching step. Then, the gate oxide layer and the polysilicon structure are formed in the trenches and protrude above a surface of the semiconductor substrate. The guard ring is formed to cover a portion of the resultant structure. At last, the electrode is formed above the guard ring and the other portion not covered by the guard ring. The protruding gate oxide layer and the protruding polysilicon structure can avoid cracks occurring in the trench structure.
    Type: Application
    Filed: June 28, 2010
    Publication date: December 30, 2010
    Applicant: PFC DEVICE CORPORATION
    Inventors: Kou-Liang CHAO, Hung-Hsin Kuo, Tse-Chuan Su, Mei-Ling Chen
  • Patent number: 7858506
    Abstract: Some embodiments include methods of forming diodes in which a first electrode is formed to have a pedestal extending upwardly from a base. At least one layer is deposited along an undulating topography that extends across the pedestal and base, and a second electrode is formed over the least one layer. The first electrode, at least one layer, and second electrode together form a structure that conducts current between the first and second electrodes when voltage of one polarity is applied to the structure, and that inhibits current flow between the first and second electrodes when voltage having a polarity opposite to said one polarity is applied to the structure. Some embodiments include diodes having a first electrode that contains two or more projections extending upwardly from a base, having at least one layer over the first electrode, and having a second electrode over the at least one layer.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: December 28, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Gurtej S. Sandhu, Chandra Mouli
  • Patent number: 7829448
    Abstract: Disclosed herein are a structure of a metal oxide semiconductor pseudomorphic high electron mobility transistor (MOS-PHEMT) suitable for use in a semiconductor device, such as a single-pole-double-throw (SPDT) switch of a monolithic microwave integrated circuit (MMIC); and a method of producing the same. The MOS-PHEMT structure is characterized in having a gate dielectric layer formed by atomic deposition from a gate dielectric selected from the group consisting of Al2O3, HfO2, La2O3, and ZrO2, and thereby rendering the semiconductor structure comprising the same, such as a high frequency switch device, to have less DC power loss, less insertion loss and better isolation.
    Type: Grant
    Filed: October 7, 2009
    Date of Patent: November 9, 2010
    Assignee: National Chiao Tung University
    Inventors: Edward Yi. Chang, Yun-Chi Wu, Yueh-Chin Lin
  • Patent number: 7754550
    Abstract: The gate oxide in the trenches of a trench type Schottky device are formed by oxidizing a layer of polysilicon deposited in trenches of a silicon or silicon carbide substrate. A small amount of the substrate is also oxidized to create a good interface between the substrate and the oxide layer which is formed. The corners of the trench are rounded by the initial formation and removal of a sacrificial oxide layer.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: July 13, 2010
    Assignee: International Rectifier Corporation
    Inventors: Davide Chiola, Zhi He
  • Patent number: 7741693
    Abstract: Trenches are formed in a semiconductor substrate, where the trenches include an outer trench and multiple inner trenches within the outer trench. A metal-oxide semiconductor (MOS) device and a trench MOS Schottky barrier (TMBS) device are also formed in the semiconductor substrate using the trenches. The MOS device could include the outer trench, and the TMBS device could include the inner trenches. At least one of the inner trenches may contact the outer trench, and/or at least one of the inner trenches may be electrically isolated from the outer trench. The MOS device could represent a trench vertical double-diffused metal-oxide semiconductor (VDMOS) device, and the TMBS device may be monolithically integrated with the trench VDMOS device in the semiconductor substrate. A guard ring that covers portions of the inner trenches and that is open over other portions of the inner trenches could optionally be formed in the semiconductor substrate.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: June 22, 2010
    Assignee: National Semiconductor Corporation
    Inventor: Terry Dyer
  • Patent number: 7666735
    Abstract: A method for forming different active thicknesses on the same silicon layer includes masking the silicon layer and exposing selected regions of the silicon layer. The thickness of the silicon layer at the exposed regions is changed, either by adding silicon or subtracting silicon from the layer at the exposed regions. Once the mask is removed, the silicon layer has regions of different active thicknesses, respectively suitable for use in different types of devices, such as diodes and transistors.
    Type: Grant
    Filed: February 10, 2005
    Date of Patent: February 23, 2010
    Assignee: Advanced Micro Devices, Inc.
    Inventors: David E. Brown, Hans Van Meer, Sey-Ping Sun
  • Patent number: 7655546
    Abstract: A depletion mode (D-mode) field effect transistor (FET) is monolithically integrated with an enhancement mode (E-mode) FET in a multi-layer structure. The multi-layer structure includes a channel layer overlaid by a barrier layer overlaid by an ohmic contact layer. Source and drain contacts of the D-mode and E-mode FETs are coupled to the ohmic contact layer. A gate contact of the D-mode and E-mode FETs is coupled to the barrier layer. An amorphized region is provided beneath the E-mode gate contact within the barrier layer. The amorphized region forms a buried E-mode Schottky contact with the barrier layer. An alternative embodiment couples the gate contact of the D-mode transistor to a first layer that overlies the barrier layer, and provides a similar D-mode amorphized region within the first layer.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: February 2, 2010
    Assignee: TriQuint Semiconductor, Inc.
    Inventor: Walter Anthony Wohlmuth
  • Patent number: 7541267
    Abstract: A method includes forming a first rectangular mesa from a layer of semiconducting material and forming a first dielectric layer around the first mesa. The method further includes forming a first rectangular mask over a first portion of the first mesa leaving an exposed second portion of the first mesa and etching the exposed second portion of the first mesa to produce a reversed T-shaped fin from the first mesa.
    Type: Grant
    Filed: June 20, 2007
    Date of Patent: June 2, 2009
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Haihong Wang, Shibly S. Ahmed, Ming-Ren Lin, Bin Yu
  • Publication number: 20090111253
    Abstract: Methods of fabricating compound semiconductor devices are described.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 30, 2009
    Inventors: Nathan Ray Perkins, Timothy Arthur Valade, Albert William Wang
  • Patent number: 7507628
    Abstract: A method of manufacturing a non-volatile memory device includes forming a trench using the shallow trench isolation (STI) method; forming a first insulating layer on a semiconductor device including the trench; forming a conductive layer on the semiconductor device including the trench; etching the conductive layer to form a conductive layer for a floating gate on an active area and to form a recessed gap-fill conductive layer on an isolation layer; forming a second insulating layer and a third insulating layer on the semiconductor substrate including the gap fill conductive layer and the conductive layer for the floating gate; and etching a portion of the second insulating layer and the third insulating layer to form an isolation structure consisting of the gap fill conductive layer, the second insulating layer and the third insulating layer on the isolation area.
    Type: Grant
    Filed: May 19, 2007
    Date of Patent: March 24, 2009
    Assignee: Hynix Semiconductor Inc.
    Inventors: Seung Hee Hong, Cheol Mo Jeong, Eun Soo Kim
  • Patent number: 7470605
    Abstract: Disclosed is a method for fabricating a MOS transistor. The present method includes the steps of: (a) forming a gate electrode including a gate insulating layer and a polysilicon gate conductive layer on an active region in a semiconductor substrate; (b) forming a metal layer over the substrate including the gate electrode; (c) heat-treating the substrate to form a polycide layer on a top surface and sidewalls of the gate electrode; (d) removing an unreacted portion of the metal layer; (e) removing the polycide layer from the top surface and sidewalls of the gate electrode, thus reducing a width of the gate electrode; and (f) forming source and drain regions in the active region adjacent to the gate electrode.
    Type: Grant
    Filed: May 30, 2006
    Date of Patent: December 30, 2008
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Jong Min Kim
  • Publication number: 20080251793
    Abstract: A junction barrier Schottky (JBS) rectifier device and a method of making the device are described. The device comprises an epitaxially grown first n-type drift layer and p-type regions forming p+-n junctions and self-planarizing epitaxially over-grown second n-type drift regions between and, optionally, on top of the p-type regions. The device may include an edge termination structure such as an exposed or buried P+ guard ring, a regrown or implanted junction termination extension (JTE) region, or a “deep” mesa etched down to the substrate. The Schottky contact to the second n-type drift region and the ohmic contact to the p-type region together serve as an anode. The cathode can be formed by ohmic contact to the n-type region on the backside of the wafer. The devices can be used in monolithic digital, analog, and microwave integrated circuits.
    Type: Application
    Filed: June 26, 2008
    Publication date: October 16, 2008
    Applicant: SemiSouth Laboratories, Inc.
    Inventors: Michael S. MAZZOLA, Lin CHENG
  • Patent number: 7429523
    Abstract: a Schottky diode having a semiconductor region is formed as follows. A plurality of charge control electrodes are formed in the semiconductor region so as to influence an electric field in the semiconductor region, wherein at least two of the charge control electrodes are adapted to be biased differently from one another. The semiconductor region is overlaid with a metal layer to thereby form a Schottky barrier therebetween.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: September 30, 2008
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Christopher Boguslaw Kocon
  • Patent number: 7375019
    Abstract: An image sensor and a method for fabricating the same are disclosed, to improve a contact quality between a contact plug and a source diffusion layer.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: May 20, 2008
    Assignee: Dongbu Electronics Co., Ltd.
    Inventor: Hee Sung Shim
  • Patent number: 7365384
    Abstract: A memory device includes isolation trenches that are formed generally parallel to and along associated strips of active area. A conductive bit line is recessed within each isolation trench such that the uppermost surface of the bit line is recessed below the uppermost surface of the base substrate. A bit line contact strap electrically couples the bit line to the active area both along a vertical dimension of the bit line strap and along a horizontal dimension across the uppermost surface of the base substrate.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: April 29, 2008
    Assignee: Micron Technology, Inc.
    Inventors: Luan C. Tran, Mark Durcan, Howard C. Kirsch
  • Patent number: 7323402
    Abstract: A fabrication process for a trench Schottky diode with differential oxide thickness within the trenches includes forming a first nitride layer on a substrate surface and subsequently forming a plurality of trenches in the substrate including, possibly, a termination trench. Following a sacrificial oxide layer formation and removal, sidewall and bottom surfaces of the trenches are oxidized. A second nitride layer is then applied to the substrate and etched such that the second nitride layer covers the oxide layer on the trench sidewalls but exposes the oxide layer on the trench bottom surfaces. The trench bottom surfaces are then re-oxidized and the remaining second nitride layer then removed from the sidewalls, resulting in an oxide layer of varying thickness being formed on the sidewall and bottom surfaces of each trench. The trenches are then filled with a P type polysilicon, the first nitride layer removed, and a Schottky barrier metal applied to the substrate surface.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: January 29, 2008
    Assignee: International Rectifier Corporation
    Inventor: Davide Chiola
  • Patent number: 7229903
    Abstract: A semiconductor structure includes a first semiconductor layer, a second semiconductor layer over the first semiconductor layer, a third semiconductor layer over the second semiconductor layer, and a fourth semiconductor layer over the third semiconductor layer. A first conductive portion is coupled to the first semiconductor layer, and a second conductive portion is formed over the first semiconductor layer.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: June 12, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Hsin-Hua P. Li, Bruce M. Green, Olin L. Hartin, Ellen Y. Lan, Charles E. Weitzel
  • Patent number: 7172933
    Abstract: A method of forming a channel region for a MOSFET device in a strained silicon layer via employment of adjacent and surrounding silicon-germanium shapes, has been developed. The method features simultaneous formation of recesses in a top portion of a conductive gate structure and in portions of the semiconductor substrate not occupied by the gate structure or by dummy spacers located on the sides of the conductive gate structure. The selectively defined recesses will be used to subsequently accommodate silicon-germanium shapes, with the silicon-germanium shapes located in the recesses in the semiconductor substrate inducing the desired strained channel region. The recessing of the conductive gate structure and of semiconductor substrate portions reduces the risk of silicon-germanium bridging across the surface of sidewall spacers during epitaxial growth of the alloy layer, thus reducing the risk of gate to substrate leakage or shorts.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: February 6, 2007
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Yi-Chun Huang, Bow-Wen Chan, Baw-Ching Perng, Lawrence Sheu, Hun-Jan Tao, Chih-Hsin Ko, Chun-Chieh Lin
  • Patent number: 7098113
    Abstract: A power lateral PNP device is disclosed which includes an epitaxial layer; a first and second collector region embedded in the epitaxial layer; an emitter region between the first and second collector regions. Therefore slots are placed in each of the regions. Accordingly, in a first approach the standard process flow will be followed until reaching the point where contact openings and metal are to be processed. In this approach slots are etched that are preferably 5 to 6 um deep and 5 to 6 um wide. These slots are then oxidized and will be subsequently metalized. When used for making metal contacts to the buried layer or for ground the oxide is removed from the bottom of the slots by an anisotropic etch. Subsequently when these slots receive metal they will provide contacts to the buried layer where this is desired and to the substrate when a ground is desired. In a second approach the above-identified process is completed up through the slot process without processing the lateral PNPs.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: August 29, 2006
    Assignee: Micrel, Inc.
    Inventors: John Durbin Husher, Ronald L. Schlupp
  • Patent number: 7074623
    Abstract: The benefits of strained semiconductors are combined with silicon-on-insulator approaches to substrate and device fabrication.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: July 11, 2006
    Assignee: AmberWave Systems Corporation
    Inventors: Anthony J. Lochtefeld, Thomas A. Langdo, Richard Hammond, Matthew T. Currie, Glyn Braithwaite, Eugene A. Fitzgerald
  • 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: 7002187
    Abstract: An integrated Schottky diode and method of manufacture of such a diode is disclosed. In a first aspect, a Schottky diode comprises a semiconductor substrate. The semiconductor substrate includes an epitaxial layer (EPI) on the substrate region. The diode includes a plurality of guard rings in the EPI layer and a plurality of oxidized slots. Finally, the diode includes metal within the plurality of slots to form a Buried Power Buss. A portion of the metal is completely oxide isolated from the other elements of the diode. In a second aspect, a method for manufacturing a Schottky diode comprises providing a substrate region, A buried N+ region providing an epitaxial (EPI) layer. The method also includes providing a plurality of guard rings in the EPI layer and providing a plurality of slots in the semiconductor substrate that is in contact with the EPI layer and the substrate region.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: February 21, 2006
    Assignee: Micrel, Inc.
    Inventor: John Durbin Husher
  • Patent number: 6921957
    Abstract: A new low forward voltage drop Schottky barrier diode and its manufacturing method are provided. The method includes steps of providing a substrate, forming plural trenches on the substrate, and forming a metal layer on the substrate having plural trenches thereon to form a barrier metal layer between the substrate and the surface metal layer for forming the Schottky barrier diode.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: July 26, 2005
    Assignees: Pyramis Corporation, Delta Electronics, Inc.
    Inventors: Jun Zeng, Ming-Jiang Zhou, Tzong-Shiann Wu
  • Patent number: 6887747
    Abstract: There is disclosed a semiconductor device in which a device isolating insulating film is formed in a periphery of a device region of a semiconductor silicon substrate device region. A side wall insulating film formed of a silicon nitride film is formed to cover the periphery of a channel region on the silicon substrate. A Ta2O5 film, and a metal gate electrode are formed inside a trench whose side wall is formed of the side wall insulating film. An interlayer insulating film is formed on the device isolating insulating film. A Schottky source/drain formed of silicide is formed on the silicon substrate in a bottom portion of the trench whose side wall is formed of the side wall insulating film and interlayer insulating film. A source/drain electrode is formed on the Schottky source/drain.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: May 3, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Atsushi Yagishita, Kouji Matsuo
  • Patent number: 6864145
    Abstract: A method is described for selectively treating the properties of a gate dielectric near corners of the gate without altering the gate dielectric in a center region of a gate channel. The method includes providing a structure having a gate opening and depositing a layer of dielectric with a high dielectric constant on a bottom surface and side walls of the gate opening. The corner regions of the high dielectric constant layer formed adjacent to the bottom surface and the side walls of the gate opening are selectively treated without altering the center region of the high dielectric constant layer formed at the bottom surface of the gate opening.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: March 8, 2005
    Assignee: Intel Corporation
    Inventors: Scott A. Hareland, Mark L. Doczy, Robert S. Chau
  • Patent number: 6855593
    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: Grant
    Filed: July 11, 2002
    Date of Patent: February 15, 2005
    Assignee: International Rectifier Corporation
    Inventors: Kohji Andoh, Davide Chiola
  • Patent number: 6844251
    Abstract: A method and apparatus are provided for improving a breakdown voltage of a semiconductor device. The method includes the steps of coupling an electrode of the silicon-carbide diode to a drift layer of the semiconductor device through a charge transfer junction, said drift layer being of a first doping type and providing a junction termination layer of a relatively constant thickness in direct contact with the drift layer of the semiconductor device and in direct contact with an outside edge of the charge transfer junction, said junction termination layer extending outwards from the outside edge of the charge transfer junction, said junction termination layer also being doped with a doping material of a second doping type in sufficient concentration to provide a charge depletion region adjacent the outside edge of the charge transfer junction when the charge transfer junction is reverse biased.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: January 18, 2005
    Inventors: Krishna Shenai, Malay Trivedi, Philip Neudeck
  • Patent number: 6825073
    Abstract: A Schottky diode structure and a method of making the same are disclosed. The method comprises following steps: firstly, a semiconductor substrate having a first conductive layer and an epi-layer doped with the same type impurities is provided. Then a first oxide layer is form on the epi layer. A patterning step to pattern first oxide layer and recess the epi layer (optional) is then followed to define guard rings. After stripping the photoresist pattern, a polycrystalline silicon layer formation is then followed. A boron and/or BF2+ ion implant is then performed. Subsequently, a high temperature drive in process and oxidation process to oxidize the polycrystalline silicon layer and drive ions is then carried out. A second mask and etch steps are then performed to open the active regions. A metallization process is then done. A third mask and etch steps are then implemented to define anode. Finally, a backside metal layer is then formed and serves as a cathode.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: November 30, 2004
    Assignee: Chip Integration Tech Co., Ltd.
    Inventor: Shye-Lin Wu
  • 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
  • Patent number: 6770548
    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: May 5, 2003
    Date of Patent: August 3, 2004
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Koon Chong So
  • Patent number: 6762098
    Abstract: An integrated circuit having a plurality of trench Schottky barrier rectifiers within one or more rectifier regions and a plurality of trench DMOS transistors within one or more transistor regions.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: July 13, 2004
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Yan Man Tsui, Koon Chong So
  • Patent number: 6740951
    Abstract: A Schottky rectifier includes a semiconductor structure having first and second opposing faces each extending to define an active semiconductor region and a termination semiconductor region. The semiconductor structure includes a cathode region of the first conductivity type adjacent the first face and a drift region of the first conductivity type adjacent the second face. The drift region has a lower net doping concentration than that of the cathode region. A plurality of trenches extends from the second face into the semiconductor structure and defines a plurality of mesas within the semiconductor structure. At least one of the trenches is located in each of the active and the termination semiconductor regions. A first insulating region is located adjacent the semiconductor structure in the plurality of trenches. A second insulating region electrically isolates the active semiconductor region from the termination semiconductor region.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: May 25, 2004
    Assignee: General Semiconductor, Inc.
    Inventors: Yan Man Tsui, Fwu-Iuan Hshieh, Koon Chong So
  • 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: 6649497
    Abstract: A method of fabricating an integrated circuit on a silicon carbide substrate is disclosed that eliminates wire bonding that can otherwise cause undesired inductance. The method includes fabricating a semiconductor device on a first surface of a silicon carbide substrate and with at least one metal contact for the device on the first surface of the substrate. The opposite, second surface of the substrate is then ground and polished until it is substantially transparent. The method then includes masking the polished second surface of the silicon carbide substrate to define a predetermined location for a via that is opposite the device metal contact on the first surface; etching the desired via through the desired masked location until the etch reaches the metal contact on the first surface; and metallizing the via to provide an electrical contact from the second surface of the substrate to the metal contact and to the device on the first surface of the substrate.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: November 18, 2003
    Assignee: Cree, Inc.
    Inventor: Zoltan Ring
  • Patent number: 6593620
    Abstract: An integrated circuit having a plurality of trench Schottky barrier rectifiers within one or more rectifier regions and a plurality of trench DMOS transistors within one or more transistor regions.
    Type: Grant
    Filed: October 6, 2000
    Date of Patent: July 15, 2003
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Yan Man Tsui, Koon Chong So
  • Patent number: 6576973
    Abstract: A vertical Schottky diode including an N-type silicon carbide layer of low doping level formed by epitaxy on a silicon carbide substrate of high doping level. The periphery of the active area of the diode is coated with a P-type epitaxial silicon carbide layer. A trench crosses the P-type epitaxial layer and penetrates into at least a portion of the height of the N-type epitaxial layer beyond the periphery of the active area. The doping level of the P-type epitaxial layer is chosen so that, for the maximum voltage that the diode is likely to be subjected to, the equipotential surfaces corresponding to approximately ¼ to ¾ of the maximum voltage extend up to the trench.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: June 10, 2003
    Assignee: STMicroelectronics S.A.
    Inventors: Emmanuel Collard, André Lhorte
  • Patent number: 6573129
    Abstract: A transistor structure is provided. This structure has a source electrode and a drain electrode. A doped cap layer of GaxIn1−xAs is disposed below the source electrode and the drain electrode and provides a cap layer opening. An undoped resistive layer of GaxIn1−xAs is disposed below the cap layer and defines a resistive layer opening in registration with the cap layer opening and having a first width. A Schottky layer of AlyIn1−yAs is disposed below the resistive layer. An undoped channel layer is disposed below the Schottky layer. A semi-insulating substrate is disposed below the channel layer. A top surface of the Schottky layer beneath the resistive layer opening provides a recess having a second width smaller than the first width. A gate electrode is in contact with a bottom surface of the recess provided by the Schottky layer.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: June 3, 2003
    Assignee: Raytheon Company
    Inventors: William E. Hoke, Katerina Hur, Rebecca McTaggart
  • Patent number: 6518152
    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: January 10, 2002
    Date of Patent: February 11, 2003
    Assignee: General Semiconductor, Inc.
    Inventors: Fwu-Iuan Hshieh, Max Chen, Koon Chong So, Yan Man Tsui
  • Patent number: 6509234
    Abstract: A method of forming a fully depleted semiconductor-on-insulator (SOI) field effect transistor (FET). The method includes forming a T-shaped gate electrode formed at least in part in a recess formed in a layer of semiconductor material and over a body region that is disposed between a source and a drain. The method includes spacing the gate electrode from the body by a gate dielectric made from a high-K material.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: January 21, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Zoran Krivokapic
  • Patent number: 6475890
    Abstract: For fabricating a field effect transistor on a semiconductor substrate in SOI (semiconductor on insulator) technology, a pillar of semiconductor material is formed on a layer of buried insulating material. The pillar has a top surface and first and second side surfaces, and the pillar has a width, a length, and a height. A masking structure is formed on a center portion of the top surface of the pillar along the length of the pillar. A top portion of the height of the pillar is etched from exposed surfaces of the top surface of the pillar down to a bottom portion of the height of the pillar to form an upside down T-shape for the pillar. A gate dielectric material is deposited on any exposed surface of the semiconductor material of the pillar for a gate length along the length of the pillar. A gate electrode material is deposited on the gate dielectric material to surround the pillar for the gate length of the pillar.
    Type: Grant
    Filed: February 12, 2001
    Date of Patent: November 5, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Bin Yu
  • Patent number: 6455403
    Abstract: A method for fabricating a Schottky diode using a shallow trench contact to reduce leakage current in the fabrication of an integrated circuit device is described. The method provides a simple and effective method for decreasing the possibility of forming a bad Schottky diode.
    Type: Grant
    Filed: January 4, 1999
    Date of Patent: September 24, 2002
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventors: Jei-Fung Hwang, Ruey-Hsing Liou, Chih-Kang Chiu