Patents by Inventor Hamza Yilmaz

Hamza Yilmaz 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: 20170250173
    Abstract: Various improvements in vertical transistors, such as IGBTs, are disclosed. The improvements include forming periodic highly-doped p-type emitter dots in the top surface region of a growth substrate, followed by growing the various transistor layers, followed by grounding down the bottom surface of the substrate, followed by a wet etch of the bottom surface to expose the heavily doped p+ layer. A metal contact is then formed over the p+ layer. In another improvement, edge termination structures utilize p-dopants implanted in trenches to create deep p-regions for shaping the electric field, and shallow p-regions between the trenches for rapidly removing holes after turn-off. In another improvement, a dual buffer layer using an n-layer and distributed n+ regions improves breakdown voltage and saturation voltage. In another improvement, p-zones of different concentrations in a termination structure are formed by varying pitches of trenches. In another improvement, beveled saw streets increase breakdown voltage.
    Type: Application
    Filed: May 16, 2017
    Publication date: August 31, 2017
    Inventor: Hamza Yilmaz
  • Publication number: 20170250270
    Abstract: Various improvements in vertical transistors, such as IGBTs, are disclosed. The improvements include forming periodic highly-doped p-type emitter dots in the top surface region of a growth substrate, followed by growing the various transistor layers, followed by grounding down the bottom surface of the substrate, followed by a wet etch of the bottom surface to expose the heavily doped p+ layer. A metal contact is then formed over the p+ layer. In another improvement, edge termination structures utilize p-dopants implanted in trenches to create deep p-regions for shaping the electric field, and shallow p-regions between the trenches for rapidly removing holes after turn-off. In another improvement, a dual buffer layer using an n-layer and distributed n+ regions improves breakdown voltage and saturation voltage. In another improvement, p-zones of different concentrations in a termination structure are formed by varying pitches of trenches. In another improvement, beveled saw streets increase breakdown voltage.
    Type: Application
    Filed: May 11, 2017
    Publication date: August 31, 2017
    Inventor: Hamza Yilmaz
  • Patent number: 9748375
    Abstract: A semiconductor power device may include a lightly doped layer formed on a heavily doped layer. One or more devices are formed in the lightly doped layer. Each device may include a body region, a source region, and one or more gate electrodes formed in corresponding trenches in the lightly doped region. Each of the trenches has a depth in a first dimension, a width in a second dimension and a length in a third dimension. The body region is of opposite conductivity type to the lightly and heavily doped layers. The source region is formed proximate the upper surface. One or more deep contacts are formed at one or more locations along the third dimension proximate one or more of the trenches. The contacts extend in the first direction from the upper surface into the lightly doped layer and are in electrical contact with the source region.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: August 29, 2017
    Assignee: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Hamza Yilmaz, Daniel Ng, Daniel Calafut, Madhur Bobde, Anup Bhalla, Ji Pan, Yeeheng Lee, Jongoh Kim
  • Publication number: 20170243745
    Abstract: Various improvements in vertical transistors, such as IGBTs, are disclosed. The improvements include forming periodic highly-doped p-type emitter dots in the top surface region of a growth substrate, followed by growing the various transistor layers, followed by grounding down the bottom surface of the substrate, followed by a wet etch of the bottom surface to expose the heavily doped p+ layer. A metal contact is then formed over the p+ layer. In another improvement, edge termination structures utilize p-dopants implanted in trenches to create deep p-regions for shaping the electric field, and shallow p-regions between the trenches for rapidly removing holes after turn-off. In another improvement, a dual buffer layer using an n-layer and distributed n+ regions improves breakdown voltage and saturation voltage. In another improvement, p-zones of different concentrations in a termination structure are formed by varying pitches of trenches. In another improvement, beveled saw streets increase breakdown voltage.
    Type: Application
    Filed: May 9, 2017
    Publication date: August 24, 2017
    Inventor: Hamza Yilmaz
  • Publication number: 20170243746
    Abstract: Various improvements in vertical transistors, such as IGBTs, are disclosed. The improvements include forming periodic highly-doped p-type emitter dots in the top surface region of a growth substrate, followed by growing the various transistor layers, followed by grounding down the bottom surface of the substrate, followed by a wet etch of the bottom surface to expose the heavily doped p+ layer. A metal contact is then formed over the p+ layer. In another improvement, edge termination structures utilize p-dopants implanted in trenches to create deep p-regions for shaping the electric field, and shallow p-regions between the trenches for rapidly removing holes after turn-off. In another improvement, a dual buffer layer using an n-layer and distributed n+ regions improves breakdown voltage and saturation voltage. In another improvement, p-zones of different concentrations in a termination structure are formed by varying pitches of trenches. In another improvement, beveled saw streets increase breakdown voltage.
    Type: Application
    Filed: May 9, 2017
    Publication date: August 24, 2017
    Inventor: Hamza Yilmaz
  • Patent number: 9741808
    Abstract: A plurality of gate trenches is formed into a semiconductor substrate in an active cell region. One or more other trenches are formed in a different region. Each gate trench has a first conductive material in lower portions and a second conductive material in upper portions. In the gate trenches, a first insulating layer separates the first conductive material from the substrate, a second insulating layer separates the second conductive material from the substrate and a third insulating material separates the first and second conductive materials. The other trenches contain part of the first conductive material in a half-U shape in lower portions and part of the second conductive material in upper portions. In the other trenches, the third insulating layer separates the first and second conductive materials. The first insulating layer is thicker than the third insulating layer, and the third insulating layer is thicker than the second.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: August 22, 2017
    Assignee: Alpha and Omage Semiconductor Inc.
    Inventors: Yeeheng Lee, Lingpeng Guan, Hongyong Xue, Yiming Gu, Yang Xiang, Terence Huang, Sekar Ramamoorthy, Wenjun Li, Hong Chang, Madhur Bobde, Paul Thorup, Hamza Yilmaz
  • Publication number: 20170236895
    Abstract: This invention discloses a semiconductor power device disposed in a semiconductor substrate comprising a lightly doped layer formed on a heavily doped layer and having an active cell area and an edge termination area. The edge termination area comprises a plurality P-channel MOSFETs. By connecting the gate to the drain electrode, the P-channel MOSFET transistors formed on the edge termination are sequentially turned on when the applied voltage is equal to or greater than the threshold voltage Vt of the P-channel MOSFET transistors, thereby optimizing the voltage blocked by each region.
    Type: Application
    Filed: January 17, 2017
    Publication date: August 17, 2017
    Inventors: Hamza Yilmaz, Madhur Bobde
  • Patent number: 9735094
    Abstract: A combined packaged power semiconductor device includes flipped top source low-side MOSFET electrically connected to top surface of a die paddle, first metal interconnection plate connecting between bottom drain of a high-side MOSFET or top source of a flipped high-side MOSFET to bottom drain of the low-side MOSFET, and second metal interconnection plate stacked on top of the high-side MOSFET chip. The high-side, low-side MOSFET and the IC controller can be packaged three-dimensionally reducing the overall size of semiconductor devices and can maximize the chip's size within a package of the same size and improves the performance of the semiconductor devices. The top source of flipped low-side MOSFET is connected to the top surface of the die paddle and thus is grounded through the exposed bottom surface of die paddle, which simplifies the shape of exposed bottom surface of the die paddle and maximizes the area to facilitate heat dissipation.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: August 15, 2017
    Assignee: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Yueh-Se Ho, Hamza Yilmaz, Yan Yun Xue, Jun Lu
  • Patent number: 9722073
    Abstract: A lateral superjunction MOSFET device includes a gate structure and a first column connected to the lateral superjunction structure. The lateral superjunction MOSFET device includes the first column to receive current from the channel when the MOSFET is turned on and to distribute the channel current to the lateral superjunction structure functioning as the drain drift region. In some embodiment, the MOSFET device includes a second column disposed in close proximity to the first column. The second column disposed near the first column is used to pinch off the first column when the MOSFET device is to be turned off and to block the high voltage being sustained by the MOSFET device at the drain terminal from reaching the gate structure. In some embodiments, the lateral superjunction MOSFET device further includes termination structures for the drain, source and body contact doped region fingers.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: August 1, 2017
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Madhur Bobde, Lingpeng Guan, Karthik Padmanabhan, Hamza Yilmaz
  • Patent number: 9704948
    Abstract: A trench type power semiconductor device with improved breakdown voltage and UIS performance and a method for preparation the device are disclosed. The trench type power semiconductor device includes a first contact hole formed in a mesa in the active area and a second contact hole formed in a mesa in an active to termination intermediate area, where the first contact hole is deeper and wider than the second contact hole.
    Type: Grant
    Filed: August 9, 2014
    Date of Patent: July 11, 2017
    Assignee: Alpha & Omega Semiconductor (Cayman), Ltd.
    Inventors: Yongping Ding, Hamza Yilmaz, Xiaobin Wang, Madhur Bobde
  • Patent number: 9704955
    Abstract: Semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In one embodiment, a method for forming a semiconductor device includes forming a first epitaxial layer on sidewalls of trenches and forming second epitaxial layer on the first epitaxial layer where charges in the doped regions along the sidewalls of the first and second trenches achieve charge balance in operation. In another embodiment, the semiconductor device includes a termination structure including an array of termination cells.
    Type: Grant
    Filed: October 19, 2016
    Date of Patent: July 11, 2017
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Hamza Yilmaz, Xiaobin Wang, Anup Bhalla, John Chen, Hong Chang
  • Patent number: 9679833
    Abstract: A method of manufacturing a semiconductor package having a small gate clip is disclosed. A first and second semiconductor chips, each of which includes a source electrode and a gate electrode at a top surface, are attached on two adjacent lead frame units of a lead frame such that the lead frame unit with the first chip formed thereon is rotated 180 degrees in relation to the other lead frame unit with the second semiconductor chip formed thereon. A first and second clip sets are mounted on the first and second semiconductor chips, wherein the first clip set is connected to the gate electrode of the first chip, the source electrode of the second chip, and their corresponding leads and the second clip set is connected to the gate electrode of the second chip, the source electrode of the first chip and their corresponding leads.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: June 13, 2017
    Assignee: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Yan Xun Xue, Hamza Yilmaz, Yueh-Se Ho, Jun Lu, Ming-Chen Lu, Hongtao Gao
  • Patent number: 9666666
    Abstract: A method of manufacturing an insulated gate bipolar transistor (IGBT) device comprising 1) preparing a semiconductor substrate with an epitaxial layer of a first conductivity type supported on the semiconductor substrate of a second conductivity type; 2) applying a gate trench mask to open a first trench and second trench followed by forming a gate insulation layer to pad the trench and filling the trench with a polysilicon layer to form the first trench gate and the second trench gate; 3) implanting dopants of the first conductivity type to form an upper heavily doped region in the epitaxial layer; and 4) forming a planar gate on top of the first trench gate and apply implanting masks to implant body dopants and source dopants to form a body region and a source region near a top surface of the semiconductor substrate.
    Type: Grant
    Filed: May 14, 2015
    Date of Patent: May 30, 2017
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Jun Hu, Madhur Bobde, Hamza Yilmaz
  • Publication number: 20170148632
    Abstract: A semiconductor device includes a superjunction structure formed using simultaneous N and P angled implants into the sidewall of a trench. The simultaneous N and P angled implants use different implant energies and dopants of different diffusion rate so that after annealing, alternating N and P thin semiconductor regions are formed. The alternating N and P thin semiconductor regions form a superjunction structure where a balanced space charge region is formed to enhance the breakdown voltage characteristic of the semiconductor device.
    Type: Application
    Filed: February 2, 2017
    Publication date: May 25, 2017
    Inventors: Karthik Padmanabhan, Madhur Bobde, Lingpeng Guan, Lei Zhang, Hamza Yilmaz
  • Publication number: 20170148910
    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: February 6, 2017
    Publication date: May 25, 2017
    Applicant: Alpha and Omega Semiconductor Incorporated
    Inventors: Lingpeng Guan, Anup Bhalla, Hamza Yilmaz
  • Patent number: 9653383
    Abstract: A semiconductor device with thick bottom metal comprises a semiconductor chip covered with a top plastic package layer at its front surface and a back metal layer at its back surface, the top plastic package layer surrounds sidewalls of the metal bumps with a top surface of the metal bumps exposing from the top plastic package layer, a die paddle for the semiconductor chip to mount thereon and a plastic package body.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: May 16, 2017
    Assignee: Alpha & Omega Semiconductor (Cayman), Ltd.
    Inventors: Hamza Yilmaz, Yan Xun Xue, Jun Lu, Ming-Chen Lu, Yan Huo, Aihua Lu
  • Publication number: 20170133473
    Abstract: A plurality of gate trenches is formed into a semiconductor substrate in an active cell region. One or more other trenches are formed in a different region. Each gate trench has a first conductive material in lower portions and a second conductive material in upper portions. In the gate trenches, a first insulating layer separates the first conductive material from the substrate, a second insulating layer separates the second conductive material from the substrate and a third insulating material separates the first and second conductive materials. The other trenches contain part of the first conductive material in a half-U shape in lower portions and part of the second conductive material in upper portions. In the other trenches, the third insulating layer separates the first and second conductive materials. The first insulating layer is thicker than the third insulating layer, and the third insulating layer is thicker than the second.
    Type: Application
    Filed: January 23, 2017
    Publication date: May 11, 2017
    Inventors: Yeeheng Lee, Lingpeng Guan, Hongyong Xue, Yiming Gu, Yang Xiang, Terence Huang, Sekar Ramamoorthy, Wenjun Li, Hong Chang, Madhur Bobde, Paul Thorup, Hamza Yilmaz
  • Publication number: 20170117386
    Abstract: A lateral super junction JFET is formed from stacked alternating P type and N type semiconductor layers over a P-epi layer supported on an N+ substrate. An N+ drain column extends down through the super junction structure and the P-epi to connect to the N+ substrate to make the device a bottom drain device. N+ source column and P+ gate column extend through the super junction but stop at the P-epi layer. A gate-drain avalanche clamp diode is formed from the bottom the P+ gate column through the P-epi to the N+ drain substrate.
    Type: Application
    Filed: February 10, 2013
    Publication date: April 27, 2017
    Inventors: Madhur Bobde, Lingpeng Guan, Anup Bhalla, Hamza Yilmaz
  • Publication number: 20170110535
    Abstract: Various improvements in vertical transistors, such as IGBTs, are disclosed. The improvements include forming periodic highly-doped p-type emitter dots in the top surface region of a growth substrate, followed by growing the various transistor layers, followed by grounding down the bottom surface of the substrate, followed by a wet etch of the bottom surface to expose the heavily doped p+ layer. A metal contact is then formed over the p+ layer. In another improvement, edge termination structures utilize p-dopants implanted in trenches to create deep p-regions for shaping the electric field, and shallow p-regions between the trenches for rapidly removing holes after turn-off. In another improvement, a dual buffer layer using an n-layer and distributed n+ regions improves breakdown voltage and saturation voltage. In another improvement, p-zones of different concentrations in a termination structure are formed by varying pitches of trenches. In another improvement, beveled saw streets increase breakdown voltage.
    Type: Application
    Filed: September 8, 2016
    Publication date: April 20, 2017
    Inventor: Hamza Yilmaz
  • Patent number: 9620630
    Abstract: Semiconductor power devices can be formed on substrate structure having a lightly doped semiconductor substrate of a first conductivity type or a second conductivity type opposite to the first conductivity type. A semiconductive first buffer layer of the first conductivity type formed above the substrate. A doping concentration of the first buffer layer is greater than a doping concentration of the substrate. A second buffer layer of the second conductivity type formed above the first buffer layer. An epitaxial layer of the second conductivity type formed above the second buffer layer. One or more heavily doped regions of the second conductivity type are formed through portions of the first buffer layer from the second buffer layer and into corresponding portions of the substrate. This abstract is provided with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Grant
    Filed: March 16, 2016
    Date of Patent: April 11, 2017
    Assignee: ALPHA AND OMEGA SEMICONDUCTOR INCORPORATED
    Inventors: Madhur Bobde, Jun Hu, Lingpeng Guan, Hamza Yilmaz, Lei Zhang, Jongoh Kim