ALEXANDRIA, Va., Dec. 16 -- United States Patent no. 12,500,089, issued on Dec. 16, was assigned to SUMCO Corp. (Tokyo).
"Wafer polishing method and wafer producing method" was invented by Chih Hao Lin (Taipei, Taiwan) and Kazushige Takaishi (Taipei, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "Provided is a wafer polishing method comprising: a step of determining a first correlation a second correlation; a step of calculating mechanical polishing rate/chemical polishing rate; a step of obtaining a relationship between the ratio of the mechanical polishing rate to the chemical polishing rate and one or more indications of wafer flatness and determining a specific range of the ratio of the mechanical...