ALEXANDRIA, Va., March 3 -- United States Patent no. 12,568,798, issued on March 3, was assigned to DISCO Corp. (Tokyo).
"Expansion method" was invented by Atsushi Ueki (Tokyo) and Takayuki Masada (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "An expansion method includes an expansion step of expanding a sheet between an outer periphery of a wafer and an inner periphery of an annular frame in a wafer unit, and a heating step of heating the sheet in its region between the outer periphery of the wafer and the inner periphery of the annular frame by a heating unit to allow slack of the sheet, the slack having been formed in the expansion step, to shrink. The region includes a first region, and a second r...