Patents Assigned to Wacker Siltronic Gesellschaft Fur Halbleitermaterialien Aktiengesellschaft
  • 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
  • Cleaning agent and method for cleaning semiconductor wafers
    Patent number: 5695572
    Abstract: A cleaning agent and method are useful for cleaning semiconductor wafers. The aqueous cleaning agent has a pH of 1 to 5, preferably a pH of 1 to 3, and contains at least one surfactant and at least one compound which belongs to a group of compounds comprising succinic acid and its derivatives. To clean the semiconductor wafers, a thin film of cleaning agent is generated on the side faces of the semiconductor wafers, preferably using a mechanical tool.
    Type: Grant
    Filed: August 10, 1995
    Date of Patent: December 9, 1997
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien Aktiengesellschaft
    Inventors: Roland Brunner, Georg Hochgesang, Anton Schnegg, Gertraud Thalhammer
  • 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
  • Heating element and process for heating crucibles
    Patent number: 5660752
    Abstract: A heating element for heating crucibles, including a cylindrical hollow body which is divided by slits into meandrous segments. The corners between adjacent lateral surfaces of the meanders are rounded. Sectional transition areas are located in the vicinity of the upper and lower edges of the meandrous segments. Each sectional area has an outer rounded edge with a radius of curvature equal to the individual length of each meandrous section.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: August 26, 1997
    Assignee: Wacker Siltronic Gesellschaft Fur Halbleitermaterialien Aktiengesellschaft
    Inventor: Peter Vilzmann
  • Process for treating semiconductor material with an acid-containing fluid
    Patent number: 5587046
    Abstract: A process for treating semiconductor material with an acid-containing fluid, has water being formed as a product of a chemical reaction. Before and/or during the treatment of the semiconductor material, phosphorus pentoxide is added to the acid-containing fluid.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: December 24, 1996
    Assignee: Wacker Siltronic Gesellschaft Fur Halbleitermaterialien Aktiengesellschaft
    Inventors: Maximilian Stadler, Gunter Schwab, Peter Romeder, Gabriele Trifellner