Patents by Inventor John H. Das

John H. Das 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: 6514876
    Abstract: A process for forming silicate glass layers on substrates is disclosed. A silicate glass layer is first deposited onto a substrate, such as a semiconductor wafer. The wafer is then placed in a thermal processing chamber and heated in the presence of a reactive gas. The object is heated to a temperature sufficient for reflow of the silicate glass. In one embodiment, the atmosphere contained within the processing chamber comprises steam in combination with a reactive gas. The reactive gas can be, for instance, hydrogen, oxygen, nitrogen, dinitrogen oxide, ozone, hydrogen peroxide, atomic and/or molecular hydrogen, or radicals or mixtures thereof.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: February 4, 2003
    Assignee: Steag RTP Systems, Inc.
    Inventors: Randhir P. S. Thakur, John H. Das, Dave Clarke
  • Patent number: 6281141
    Abstract: A process for producing thin dielectric films is disclosed. In particular, the process is directed to forming oxide films having a thickness of less than about 60 angstroms. The oxide films can be doped with an element, such as nitrogen or boron. For example, in one embodiment, an oxynitride coating can be formed on a semiconductor wafer. According to the present invention, the very thin coatings are formed by reacting a gas with a semiconductor wafer while the temperature of the wafer is being increased in a rapid thermal processing chamber to a maximum temperature. According to the process, primarily all of the coating is formed during the “ramp up” portion of the heating cycle. Consequently, the wafer is maintained at the maximum target temperature for a very short period of time.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: August 28, 2001
    Assignee: Steag RTP Systems, Inc.
    Inventors: John H. Das, Randhir P. S. Thakur
  • Patent number: 5627427
    Abstract: A micrometer scale emitter tip or array is disclosed having precisely located tips and surrounding gates. A silicide on the tips reduces tip work function.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: May 6, 1997
    Assignee: Cornell Research Foundation, Inc.
    Inventors: John H. Das, Noel C. MacDonald, James W. Mayer, James P. Spallas