Patents Assigned to Seiko Epson Instruments Inc.
  • Semiconductor device
    Patent number: 8242580
    Abstract: Provided is a method which is capable of producing polycrystalline silicon resistors with a high ratio accuracy so that a precision resistor circuit may be designed. A semiconductor device has a structure in which an occupation area of a metal portion covering a low concentration impurity region constituting each of the polycrystalline silicon resistors is adjusted so that ratio accuracy may be further corrected after a resistance is corrected.
    Type: Grant
    Filed: February 4, 2010
    Date of Patent: August 14, 2012
    Assignee: Seiko Epson Instruments Inc.
    Inventor: Akiko Tsukamoto