Patents by Inventor Tso-Chi Chang

Tso-Chi 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).

  • Method for making micro-electromechanical system devices
    Patent number: 7824945
    Abstract: A method for making micro-electromechanical system devices includes: (a) forming a sacrificial layer on a device wafer; (b) forming a plurality of loop-shaped through-holes in the sacrificial layer so as to form the sacrificial layer into a plurality of enclosed portions; (c) forming a plurality of cover caps on the sacrificial layer such that the cover caps respectively enclose the enclosed portions of the sacrificial layer; (d) forming a device through-hole in each of active units of the device wafer so as to form an active part suspended in each of the active units; and (e) removing the enclosed portions of the sacrificial layer through the device through-holes in the active units of the device wafer.
    Type: Grant
    Filed: October 2, 2008
    Date of Patent: November 2, 2010
    Assignee: Asia Pacific Microsystems, Inc.
    Inventors: Tso-Chi Chang, Mingching Wu
  • Method for Making Micro-Electromechanical System Devices
    Publication number: 20090311819
    Abstract: A method for making micro-electromechanical system devices includes: (a) forming a sacrificial layer on a device wafer; (b) forming a plurality of loop-shaped through-holes in the sacrificial layer so as to form the sacrificial layer into a plurality of enclosed portions; (c) forming a plurality of cover caps on the sacrificial layer such that the cover caps respectively enclose the enclosed portions of the sacrificial layer; (d) forming a device through-hole in each of active units of the device wafer so as to form an active part suspended in each of the active units; and (e) removing the enclosed portions of the sacrificial layer through the device through-holes in the active units of the device wafer.
    Type: Application
    Filed: October 2, 2008
    Publication date: December 17, 2009
    Inventors: Tso-Chi Chang, Mingching Wu