Patents by Inventor Steven H. Moffat

Steven H. Moffat 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: 7357874
    Abstract: The invention relates to a method of fabrication of staggered vertical comb drive actuators with relaxed lateral alignment tolerances. A device layer of a wafer is first etched from a front side using a self-aligned two-layer mask to define interdigited fingers of both moving and stationary combs. A second etch step is used for vertically thinning one of the two sets of fingers by selectively removing their top portions. The front side of the wafer is then bonded to a carrier wafer. The wafer is then selectively etched from the back side of the device layer so as to remove lower portions of the second set of fingers, thereby forming interdigited moving and stationary combs having vertically offset fingers.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: April 15, 2008
    Assignee: JDS Uniphase Corporation
    Inventors: Steven H. Moffat, John M. Miller
  • Publication number: 20070241076
    Abstract: The invention relates to a method of fabrication of staggered vertical comb drive actuators with relaxed lateral alignment tolerances. A device layer of a wafer is first etched from a front side using a self-aligned two-layer mask to define interdigited fingers of both moving and stationary combs. A second etch step is used for vertically thinning one of the two sets of fingers by selectively removing their top portions. The front side of the wafer is then bonded to a carrier wafer. The wafer is then selectively etched from the back side of the device layer so as to remove lower portions of the second set of fingers, thereby forming interdigited moving and stationary combs having vertically offset fingers.
    Type: Application
    Filed: April 11, 2007
    Publication date: October 18, 2007
    Inventors: Steven H. Moffat, John M. Miller
  • Patent number: 5841342
    Abstract: A low insertion loss, wide bandwidth, microwave switch has a superconducting transmission line that can reversibly go from a superconducting state to a normal state by the application of a DC voltage. When in the normal state, the switch is "off" and microwave signals are attenuated. To reduce the voltage necessary to cause switching, the width of the transmission line is decreased. This decrease in voltage is accomplished in a controlled manner so that there are no spurious reflections produced on the line, resulting in a wide operating bandwidth. Previous microwave switches use other means to switch between superconducting and normal and suffer from disadvantages such as relatively slow switching time, complexity or narrow bandwidths as a result.
    Type: Grant
    Filed: October 13, 1995
    Date of Patent: November 24, 1998
    Assignee: Com Dev Ltd.
    Inventors: Frank A. Hegmann, Steven H. Moffat, John S. Preston, Darcy G. Poulin