Patents by Inventor Shang-De T. Chang

Shang-De T. Chang 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).

  • Patent number: 5581504
    Abstract: A NAND Flash EEPROM string is formed in a common N-well and includes a plurality of P-channel MOS stacked-gate storage transistors and P-channel MOS string and ground select transistors. In the preferred embodiment, each P-channel storage transistor is programmed via hot electron injection from the depletion region proximate its P+ drain/N-well junction and erased via electron tunneling from its floating gate to its P-type channel as well as to its P+ source and P+ drain regions without requiring high programming and erasing voltages, respectively. Further, high P/N junction biases are not required during programming or erasing operations. This allows the dimensions of the present embodiments to be reduced to a size smaller than that of comparable conventional N-channel NAND Flash EEPROM strings.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: December 3, 1996
    Assignee: Programmable Microelectronics Corp.
    Inventor: Shang-De T. Chang