Patents by Inventor Daniel O. Clawson

Daniel O. Clawson 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: 6116032
    Abstract: A method for reducing particulate generation from regeneration of cryogenic vacuum pumps. The method comprises controlling a pressure ramp rate inside the cryopump during an initial introduction of a regeneration gas into the cryopump. Preferably, the pressure ramp rate is controlled by maintaining a first pressure ramp rate, preferably between about 0.03 T/s and 0.15 T/s, until a first pressure of about 0.3 T is reached inside the cryopump and maintaining a second pressure ramp rate between about 1 T/s and 5 T/s until the surface in the cryopump reaches an intermediate temperature between about 40 K and 100 K. Preferably, the temperature ramp rate is also controlled by heating the surface at a temperature ramp rate between about 0.1 K/s and about 0.5 K/s until the intermediate temperature has been reached. Preferably, the temperature ramp rate is controlled by regulating the flow of an inert gas into the cryopump using a flow restriction device.
    Type: Grant
    Filed: January 12, 1999
    Date of Patent: September 12, 2000
    Assignee: Applied Materials, Inc.
    Inventors: Glen T. Mori, Daniel O. Clawson