Patents by Inventor Bernd Passer

Bernd Passer 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 removing damaged crystal regions from silicon wafers
    Patent number: 5911889
    Abstract: A method is provided to remove crystal regions from silicon wafers which are damaged as a consequence of mechanical machining of the silicon wafers. The silicon wafers are pretreated with an aqueous solution containing hydrogen fluoride. Then the wafers are etched in an aqueous solution exposed to ultrasound and containing alkali metal hydroxide at temperatures from 55.degree. C. to 95.degree. C.
    Type: Grant
    Filed: April 8, 1996
    Date of Patent: June 15, 1999
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien Aktiengesellschaft
    Inventors: Laszlo Fabry, Bernd Passer, Edeltraud Steiger
  • Process for treating disk-shaped workpieces with a liquid
    Patent number: 5693149
    Abstract: A process for treating disk-shaped workpieces with a liquid in a chamber which can be sealed in gas-tight manner, in which the workpieces stacked in a transport rack are brought into contact with the fed-in liquid in the closed chamber, the liquid is conducted away out of the chamber and noxious vapors or gases originating from the liquid are scrubbed out and are conducted away out of the chamber in the dissolved condition.
    Type: Grant
    Filed: April 17, 1996
    Date of Patent: December 2, 1997
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien Aktiengesellschaft
    Inventors: Bernd Passer, Rudolf Wengbauer, Ludwig Pichlmeier