Patents by Inventor Kok-Keong Lew

Kok-Keong Lew 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 of producing epitaxial layers with low basal plane dislocation concentrations
    Patent number: 8652255
    Abstract: A method of: flowing a silicon source gas, a carbon source gas, and a carrier gas into a growth chamber under growth conditions to epitaxial grow silicon carbide on a wafer in the growth chamber; stopping or reducing the flow of the silicon source gas to interrupt the silicon carbide growth and maintaining the flow of the carrier gas while maintaining an elevated temperature in the growth chamber for a period of time; and resuming the flow of the silicon source gas to reinitiate silicon carbide growth. The wafer remains in the growth chamber throughout the method.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: February 18, 2014
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Robert E Stahlbush, Brenda L VanMil, Kok-Keong Lew, Rachael L Myers-Ward, David Kurt Gaskill, Charles R. Eddy, Jr.
  • Tracking carbon to silicon ratio during silicon carbide growth
    Patent number: 8603243
    Abstract: A method of: supplying sources of carbon and silicon into a chemical vapor deposition chamber; collecting exhaust gases from the chamber; performing mass spectrometry on the exhaust gases; and correlating a partial pressure of a carbon species in the exhaust gases to a carbon:silicon ratio in the chamber.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: December 10, 2013
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Brenda L VanMil, Kok-Keong Lew, Rachael L Myers-Ward, Charles R. Eddy, Jr., David Kurt Gaskill
  • TRACKING CARBON TO SILICON RATIO IN SITU DURING SILICON CARBIDE GROWTH
    Publication number: 20100024719
    Abstract: A method of: supplying sources of carbon and silicon into a chemical vapor deposition chamber; collecting exhaust gases from the chamber; performing mass spectrometry on the exhaust gases; and correlating a partial pressure of a carbon species in the exhaust gases to a carbon:silicon ratio in the chamber.
    Type: Application
    Filed: July 31, 2008
    Publication date: February 4, 2010
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Brenda L. VanMil, Kok-Keong Lew, Rachael L. Myers-Ward, Charles R. Eddy, JR., David Kurt Gaskill
  • METHOD OF PRODUCING EPITAXIAL LAYERS WITH LOW BASAL PLANE DISLOCATION CONCENTRATIONS
    Publication number: 20090114148
    Abstract: A method of: flowing a silicon source gas, a carbon source gas, and a carrier gas into a growth chamber under growth conditions to epitaxial grow silicon carbide on a wafer in the growth chamber; stopping or reducing the flow of the silicon source gas to interrupt the silicon carbide growth and maintaining the flow of the carrier gas while maintaining an elevated temperature in the growth chamber for a period of time; and resuming the flow of the silicon source gas to reinitiate silicon carbide growth. The wafer remains in the growth chamber throughout the method.
    Type: Application
    Filed: October 9, 2008
    Publication date: May 7, 2009
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Robert E. Stahlbush, Brenda L. VanMil, Kok-Keong Lew, Rachael L. Myers-Ward, David Kurt Gaskill, Charles R. Eddy, JR.