Patents Represented by Attorney Taijoloff and Kelly LLP
  • Patent number: 7749930
    Abstract: An ideal quartz glass for a wafer jig for use in an environment having an etching effect is distinguished by both high purity and high resistance to dry etching. To indicate a quartz glass that substantially fulfills these requirements, it is suggested according to the invention that the quartz glass is doped with nitrogen at least in a near-surface area, has a mean content of metastable hydroxyl groups of less than 30 wt ppm and that its fictive temperature is below 1250° C. and its viscosity is at least 1013 dPa·s at a temperature of 1200° C. An economic method for producing such a quartz glass comprises the following method steps: melting an SiO2 raw material to obtain a quartz glass blank, the SiO2 raw material or the quartz glass blank being subjected to a dehydration measure, heating the SiO2 raw material or the quartz glass blank to a nitriding temperature in the range between 1050° C. and 1850° C.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: July 6, 2010
    Assignee: Heraeus Quarzglas GmbH & Co. KG
    Inventors: Juergen Weber, Tobias Pogge, Martin Trommer, Bodo Kuehn, Ulrich Kirst, Waltraud Werdecker