{
  "patent_number": "US RE48965",
  "country": "US",
  "title": "How to Stop Transistors from Wearing Out in Radio Frequency Chips",
  "original_title": "USRE48965E1 - Method and apparatus improving gate oxide reliability by controlling accumulated charge",
  "summary": "A method for extending the lifespan of silicon-on-insulator transistors by using a special sink to drain away charge that causes gate oxide breakdown.",
  "what_it_does": "This patent describes a technique to prevent the premature failure of transistors used in radio frequency (RF) switches. When transistors are built on a silicon-on-insulator (SOI) substrate, they can accumulate unwanted electrical charge in their body, which stresses the thin gate oxide layer and leads to time-dependent dielectric breakdown (TDDB). The invention adds an 'accumulated charge sink' (ACS) to the transistor body. By applying a negative bias voltage to this sink, the system actively removes the accumulated charge, keeping the gate oxide healthy and extending the life of the device.",
  "what_it_does_not_cover": [
    "Does not cover standard bulk silicon MOSFETs that do not use an SOI substrate.",
    "Does not cover charge control methods that rely solely on positive bias voltages.",
    "Does not cover transistors lacking a dedicated body contact or sink for charge removal."
  ],
  "filed": "2019-12-11",
  "granted": "2022-03-08",
  "expires": null,
  "status": "active",
  "holder": "PSemi Corp",
  "holder_url": "https://patentbrief.org/company/psemi-corp",
  "inventors": [
    {
      "name": "Tae Youn Kim",
      "url": "https://patentbrief.org/inventor/tae-youn-kim"
    },
    {
      "name": "Christopher N. Brindle",
      "url": "https://patentbrief.org/inventor/christopher-n-brindle"
    },
    {
      "name": "Michael A. Stuber",
      "url": "https://patentbrief.org/inventor/michael-a-stuber"
    },
    {
      "name": "Dylan J. Kelly",
      "url": "https://patentbrief.org/inventor/dylan-j-kelly"
    },
    {
      "name": "George P. Imthurn",
      "url": "https://patentbrief.org/inventor/george-p-imthurn"
    },
    {
      "name": "Alexander Dribinsky",
      "url": "https://patentbrief.org/inventor/alexander-dribinsky"
    },
    {
      "name": "Clint L. Kemerling",
      "url": "https://patentbrief.org/inventor/clint-l-kemerling"
    },
    {
      "name": "Robert B. Welstand",
      "url": "https://patentbrief.org/inventor/robert-b-welstand"
    },
    {
      "name": "Mark L. Burgener",
      "url": "https://patentbrief.org/inventor/mark-l-burgener"
    }
  ],
  "times_cited": 0,
  "tags": [
    "semiconductors",
    "telecommunications",
    "consumer_electronics"
  ],
  "abstract": "A method and apparatus are disclosed for use in improving the gate oxide reliability of semiconductor-on-insulator (SOI) metal-oxide-silicon field effect transistor (MOSFET) devices using accumulated charge control (ACC) techniques. The method and apparatus are adapted to remove, reduce, or otherwise control accumulated charge in SOI MOSFETs, thereby yielding improvements in FET performance characteristics. In one embodiment, a circuit comprises a MOSFET, operating in an accumulated charge regime, and means for controlling the accumulated charge, operatively coupled to the SOI MOSFET. A first determination is made of the effects of an uncontrolled accumulated charge on time dependent dielectric breakdown (TDDB) of the gate oxide of the SOI MOSFET. A second determination is made of the effects of a controlled accumulated charge on TDDB of the gate oxide of the SOI MOSFET. The SOI MOSFET is adapted to have a selected average time-to-breakdown, responsive to the first and second determinations, and the circuit is operated using techniques for accumulated charge control operatively coupled to the SOI MOSFET. In one embodiment, the accumulated charge control techniques include using an accumulated charge sink operatively coupled to the SOI MOSFET body.",
  "url": "https://patentbrief.org/patent/us/RE48965/google-play-store",
  "markdown_url": "https://patentbrief.org/patent/us/RE48965/google-play-store/md",
  "google_patents_url": "https://patents.google.com/patent/USRE48965",
  "relatedPatents": []
}