ALEXANDRIA, Va., March 5 -- United States Patent no. 12,241,924, issued on March 4, was assigned to FemtoMetrix Inc. (Los Angeles).
"Wafer metrology technologies" was invented by Viktor Koldiaev (Morgan Hill, Calif.), Marc Kryger (Fountain Valley, Calif.) and John Changala (Tustin, Calif.).
According to the abstract* released by the U.S. Patent & Trademark Office: "Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide...