US Patent Issued to SUMCO on May 19 for "Flat epitaxial wafer having minimal thickness variation" (Japanese Inventor)

ALEXANDRIA, Va., May 19 -- United States Patent no. 12,635,427, issued on May 19, was assigned to SUMCO Corp. (Tokyo).

"Flat epitaxial wafer having minimal thickness variation" was invented by Naoyuki Wada (Arita-cho, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "An epitaxial wafer includes a silicon substrate having a top surface and an epitaxial layer on said top surface, wherein the epitaxial layer has a thickness in a range of 0.3 micro metre to 1.0 micro metre, and a thickness variation of 1% or less. A method of preparing such epitaxial wafer includes placing a silicon substrate on a susceptor in an epitaxial reactor; rotating the susceptor at a rotation rate (D); and applying a source gas in th...