US Patent Issued to KLA on Feb. 25 for "Process window qualification modulation layouts" (British, Belgian, American Inventors)

ALEXANDRIA, Va., Feb. 26 -- United States Patent no. 12,235,224, issued on Feb. 25, was assigned to KLA Corp. (Milpitas, Calif.).

"Process window qualification modulation layouts" was invented by Andrew Cross (Hale, Great Britain), Kaushik Sah (Holsbeek, Belgium) and Martin Plihal (San Francisco).

According to the abstract* released by the U.S. Patent & Trademark Office: "Process window qualification (PWQ) layouts can be used to determine a presence of a pattern anomaly associated with the pattern, patterning process, or patterning apparatus. For example, a modulated die or field can be compared to a slightly lower offset modulated die or field. In another example, the high to low corners for a particular condition or combination of condi...