Patents by Inventor Anup Bhalla

Anup Bhalla has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20140054758
    Abstract: The present invention is directed to a lead-frame having a stack of semiconductor dies with interposed metalized clip structure. Level projections extend from the clip structure to ensure that the clip structure remains level during fabrication.
    Type: Application
    Filed: November 4, 2013
    Publication date: February 27, 2014
    Applicant: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Hamza Yilmaz, Xiaotian Zhang, Yan Xun Xue, Anup Bhalla, Jun Lu, Kai Liu, Yueh-Se So, John Amato
  • Publication number: 20140048846
    Abstract: Transistor devices can be fabricated with an integrated diode using a self-alignment. The device includes a doped semiconductor substrate having one or more electrically insulated gate electrodes formed in trenches in the substrate. One or more body regions are formed in a top portion of the substrate proximate each gate trench. One or more source regions are formed in a self-aligned fashion in a top portion of the body regions proximate each gate trench. One or more thick insulator portions are formed over the gate electrodes on a top surface of the substrate with spaces between adjacent thick insulator portions. A metal is formed on top of the substrate over the thick insulator portions. The metal forms a self-aligned contact to the substrate through the spaces between the thick insulator portions. An integrated diode is formed under the self-aligned contact.
    Type: Application
    Filed: October 23, 2013
    Publication date: February 20, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Sik Lui, Anup Bhalla
  • Publication number: 20140042490
    Abstract: Semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In one embodiment, a semiconductor device is formed in a first semiconductor layer having trenches and mesas formed thereon where the trenches extend from the top surface to the bottom surface of the first semiconductor layer. The semiconductor device includes semiconductor regions formed on the bottom surface of the mesas of the first semiconductor layer.
    Type: Application
    Filed: October 21, 2013
    Publication date: February 13, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Hamza Yilmaz, Xiaobin Wang, Anup Bhalla, John Chen, Hong Chang
  • Publication number: 20140035116
    Abstract: A semiconductor package and it manufacturing method includes a lead frame having a die pad, and a source lead with substantially a V groove disposed on a top surface. A semiconductor chip disposed on the die pad. A metal plate connected to a top surface electrode of the chip having a bent extension terminated in the V groove in contact with at least one of the V groove sidewalls.
    Type: Application
    Filed: October 17, 2013
    Publication date: February 6, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Yan Xun Xue, Yueh-Se Ho, Hamza Yilmaz, Anup Bhalla, Jun Lu, Kai Liu
  • Patent number: 8643135
    Abstract: This invention discloses a semiconductor power device disposed in a semiconductor substrate and having an active cell area and an edge termination area wherein the edge termination area comprises a wide trench filled with a field-crowding reduction filler and a buried field plate buried under a top surface of the semiconductor substrate and laterally extended over a top portion of the field crowding field to move a peak electric field laterally away from the active cell area. In a specific embodiment, the field-crowding reduction filler comprises a silicon oxide filled in the wide trench.
    Type: Grant
    Filed: May 31, 2011
    Date of Patent: February 4, 2014
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Madhur Bobde, Sik K Lui, Anup Bhalla
  • Patent number: 8642429
    Abstract: A semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD is disclosed. A bulk semiconductor layer (BSL) is provided with a thickness BSLT>TCD. A large trench top area (LTTA) is mapped out atop BSL with its geometry equal to OFLDT. The LTTA is partitioned into interspersed, complementary interim areas ITA-A and ITA-B. Numerous interim vertical trenches of depth TCD are created into the top BSL surface by removing bulk semiconductor materials corresponding to ITA-B. The remaining bulk semiconductor materials corresponding to ITA-A are converted into oxide. If any residual space is still left between the so-converted ITA-A, the residual space is filled up with oxide deposition. Importantly, the geometry of all ITA-A and ITA-B should be configured simple and small enough to facilitate fast and efficient processes of oxide conversion and oxide filling.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: February 4, 2014
    Assignee: Alpha & Omega Semiconductor, Inc.
    Inventors: Xiaobin Wang, Anup Bhalla, Yeeherg Lee
  • Patent number: 8643071
    Abstract: A MOSFET device includes one or more active device structures and one or more dummy structures formed from semiconductor drift region and body regions. The dummy structures are electrically connected in parallel to the active device structures. Each dummy structure includes an electrically insulated snubber electrode formed proximate the body region and the drift region, an insulator portion formed over the snubber electrode and a top surface of the body region, and one or more electrical connections between the snubber electrode and portions of the body region and a source electrode. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: February 4, 2014
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Ji Pan, Daniel Ng, Anup Bhalla
  • Publication number: 20140027819
    Abstract: A corner layout for a semiconductor device that maximizes the breakdown voltage is disclosed. The device includes first and second subsets of the striped cell arrays. The ends of each striped cell in the first array is spaced a uniform distance from the nearest termination device structure. In the second subset, the ends of striped cells proximate a corner of the active cell region are configured to maximize breakdown voltage by spacing the ends of each striped cell a non-uniform distance from the nearest termination device structure. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Application
    Filed: July 30, 2012
    Publication date: January 30, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Lingpeng Guan, Anup Bhalla
  • Publication number: 20140027840
    Abstract: The present disclosure describes a termination structure for a high voltage semiconductor transistor device. The termination structure is composed of at least two termination zones and an electrical disconnection between the body layer and the edge of the device. A first zone is configured to spread the electric field within the device. A second zone is configured to smoothly bring the electric field back up to the top surface of the device. The electrical disconnection prevents the device from short circuiting the edge of the device. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Application
    Filed: July 30, 2012
    Publication date: January 30, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Lingpeng Guan, Anup Bhalla, Hamza Yilmaz
  • Publication number: 20140027841
    Abstract: A semiconductor power device formed in a semiconductor substrate comprising a highly doped region near a top surface of the semiconductor substrate on top of a lightly doped region supported by a heavily doped region. The semiconductor power device further comprises source trenches opened into the highly doped region filled with conductive trench filling material in electrical contact with the source region near the top surface. The semiconductor power device further comprises buried P-regions disposed below the source trenches and doped with dopants of opposite conductivity from the highly doped region. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Application
    Filed: July 30, 2012
    Publication date: January 30, 2014
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Anup Bhalla, Hamza Yilmaz, Madhur Bobde, Lingpeng Guan, Jun Hu, Jongoh Kim, Yongping Ding
  • Patent number: 8637926
    Abstract: An oxide termination semiconductor device may comprise a plurality of gate trenches, a gate runner, and an insulator termination trench. The gate trenches are located in an active region. Each gate trench includes a conductive gate electrode. The insulator termination trench is located in a termination region that surrounds the active region. The insulator termination trench is filled with an insulator material to form an insulator termination for the semiconductor device. The device can be made using a three-mask or four-mask process.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: January 28, 2014
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Sik Lui, Anup Bhalla
  • Patent number: 8637368
    Abstract: Fabricating a semiconductor device includes: forming a gate trench in an epitaxial layer overlaying a semiconductor substrate; disposing gate material in the gate trench; forming a body in the epitaxial layer; forming a source in the body; forming an active region contact trench that has a varying trench depth; and disposing a contact electrode within the active region contact trench. Forming the active region contact trench includes performing a first etch to form a first contact trench depth associated with a first region, and performing a second etch to form a second contact trench depth associated with a second region. The first contact trench depth is substantially different from the second contact trench depth.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: January 28, 2014
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Anup Bhalla, Xiaobin Wang
  • Publication number: 20130341689
    Abstract: Self-aligned charge balanced semiconductor devices and methods for forming such devices are disclosed. One or more planar gates are formed over a semiconductor substrate of a first conductivity type. One or more deep trenches are etched in the semiconductor self-aligned to the planar gates. The trenches are filled with a semiconductor material of a second conductivity type such that the deep trenches are charge balanced with the adjacent regions of the semiconductor substrate Source and body regions are formed by implanting dopants onto the filled trenches. This process can form self-aligned charge balanced devices with a cell pitch less than 12 microns.
    Type: Application
    Filed: August 26, 2013
    Publication date: December 26, 2013
    Applicant: Alpha & Omega Semiconductor Incorporated
    Inventors: John Chen, Yeeheng Lee, Lingpeng Guan, Moses Ho, Wilson Ma, Anup Bhalla, Hamza Yilmaz
  • Publication number: 20130334599
    Abstract: A MOSFET device includes one or more active device structures and one or more dummy structures formed from semiconductor drift region and body regions. The dummy structures are electrically connected in parallel to the active device structures. Each dummy structure includes an electrically insulated snubber electrode formed proximate the body region and the drift region, an insulator portion formed over the snubber electrode and a top surface of the body region, and one or more electrical connections between the snubber electrode and portions of the body region and a source electrode. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Application
    Filed: June 14, 2012
    Publication date: December 19, 2013
    Applicant: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Ji Pan, Daniel Ng, Anup Bhalla
  • Publication number: 20130328121
    Abstract: A semiconductor power device includes a thick bottom insulator formed in a lower portion of a trench in a semiconductor epitaxial region. An electrically conductive gate electrode is formed in the trench above the bottom insulator. The gate electrode is electrically insulated from the epitaxial region by the bottom insulator and a gate insulator. Charge is deliberately induced in the thick bottom insulator proximate an interface between the bottom insulator and the epitaxial semiconductor region. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Application
    Filed: June 6, 2012
    Publication date: December 12, 2013
    Inventors: Xiaobin Wang, Anup Bhalla, Daniel Ng
  • Patent number: 8597998
    Abstract: Fabricating a semiconductor device includes forming a mask on a substrate having a top substrate surface; forming a gate trench in the substrate, through the mask; depositing gate material in the gate trench; removing the mask to leave a gate structure; implanting a body region; implanting a source region; forming a source body contact trench having a trench wall and a trench bottom; forming a plug in the source body contact trench, wherein the plug extends below a bottom of the body region; and disposing conductive material in the source body contact trench, on top of the plug.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: December 3, 2013
    Assignee: Alpha & Omega Semiconductor Limited
    Inventors: Anup Bhalla, Sik K. Lui, Tiesheng Li
  • Patent number: 8598623
    Abstract: A termination structure for a semiconductor device includes an array of termination cells formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In other embodiments, semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: December 3, 2013
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Hamza Yilmaz, Xiaobin Wang, Anup Bhalla, John Chen, Hong Chang
  • Publication number: 20130309823
    Abstract: A semiconductor device includes a plurality of trenches including active gate trenches in an active area and gate runner/termination trenches and shield electrode pickup trenches in a termination area outside the active area. The gate runner/termination trenches include one or more trenches that define a mesa located outside an active area. A first conductive region is formed in the plurality of trenches. An intermediate dielectric region and termination protection region are formed in the trenches that define the mesa. A second conductive region is formed in the portion of the trenches that define the mesa. The second conductive region is electrically isolated from the first conductive region by the intermediate dielectric region. A first electrical contact is made to the second conductive regions and a second electrical contact to the first conductive region in the shield electrode pickup trenches. One or more Schottky diodes are formed within the mesa.
    Type: Application
    Filed: July 23, 2013
    Publication date: November 21, 2013
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Yi Su, Daniel Ng, Anup Bhalla, Hong Chang, Jongoh Kim, John Chen
  • Publication number: 20130309816
    Abstract: A semiconductor encapsulation comprises a lead frame further comprising a chip carrier and a plurality of pins in adjacent to the chip carrier. A plurality of grooves opened from an upper surface of the chip carrier partially dividing the chip carrier into a plurality of chip mounting areas. A bottom portion of the grooves is removed for completely isolate each chip mounting area, wherein a width of the bottom portion of the grooves removed is smaller than a width of the grooves. In one embodiment, a groove is located between the chip carrier and the pins with a bottom portion of the groove removed for isolate the pins from the chip carrier, wherein a width of the bottom of the grooves removed is smaller than a width of the grooves.
    Type: Application
    Filed: July 25, 2013
    Publication date: November 21, 2013
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Yan Xun Xue, Anup Bhalla, Jun Lu
  • Patent number: 8586414
    Abstract: A semiconductor package and it manufacturing method includes a lead frame having a die pad, and a source lead with substantially a V groove disposed on a top surface. A semiconductor chip disposed on the die pad. A metal plate connected to a top surface electrode of the chip having a bent extension terminated in the V groove in contact with at least one of the V groove sidewalls.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: November 19, 2013
    Assignee: Alpha & Omega Semiconductor, Inc.
    Inventors: Yan Xun Xue, Yueh-Se Ho, Hamza Yilmaz, Anup Bhalla, Jun Lu, Kal Liu