Patents by Inventor Cheng-Lieh Wang

Cheng-Lieh Wang 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: 20020132433
    Abstract: The present invention provides a method of preventing fluorine ions from residing in a gate to result in boron ion penetration into a gate oxide on a semiconductor wafer. A substrate, an oxide layer, a conductive layer, an anti-reflection coating (ARC), and a photoresist layer positioned on the ARC defining patterns of a gate, are formed, respectively, on the semiconductor wafer. The method first involves an etching process to remove portions of both the ARC and the conductive layer uncovered by the photoresist layer to form the gate and a gate oxide layer. After the photoresist layer is stripped, an ion implantation process is performed using the gate covered by the ARC as hard mask and boron fluoride (BF2+) as the dopant to form lightly doped drains (LDD) in the substrate adjacent to the gate. Then, a spacer is formed around the gate after the ARC is removed. Finally, the method is completed with the formation of a source and a drain in the substrate adjacent to the spacer after the ARC is stripped.
    Type: Application
    Filed: March 13, 2001
    Publication date: September 19, 2002
    Inventor: Cheng-Lieh Wang
  • Patent number: 6440809
    Abstract: The present invention provides a method of preventing fluorine ions from residing in a gate to result in boron ion penetration into a gate oxide on a semiconductor wafer. A substrate, an oxide layer, a conductive layer, an anti-reflection coating (ARC), and a photoresist layer positioned on the ARC defining patterns of a gate, are formed, respectively, on the semiconductor wafer. The method first involves an etching process to remove portions of both the ARC and the conductive layer uncovered by the photoresist layer to form the gate and a gate oxide layer. After the photoresist layer is stripped, an ion implantation process is performed using the gate covered by the ARC as hard mask and boron fluoride (BF2+) as the dopant to form lightly doped drains (LDD) in the substrate adjacent to the gate. Then, a spacer is formed around the gate after the ARC is removed. Finally, the method is completed with the formation of a source and a drain in the substrate adjacent to the spacer after the ARC is stripped.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: August 27, 2002
    Assignee: United Microelectronics Corp.
    Inventor: Cheng-Lieh Wang
  • Patent number: 6363005
    Abstract: A method of increasing the operating speed of an SRAM device. The SRAM device is constructed from a plurality of loads and a plurality of NMOS transistors. A positive voltage is applied to the substrate of the NMOS transistors when data needs to be read from the SRAM device or written to the SRAM device. The positive voltage increases the channel width between the source and the drain terminal of the NMOS transistors so that a higher current is produced and operating speed of the device is increased. An earth voltage is applied to the substrate when the SRAM device is in a standby mode to prevent current leakage.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: March 26, 2002
    Assignee: United Microelectronics Corp.
    Inventors: Cheng-Lieh Wang, Cheng-Nan Lin