ALEXANDRIA, Va., Jan. 28 -- United States Patent no. 12,538,767, issued on Jan. 27, was assigned to UNITED MICROELECTRONICS CORP. (Hsin-Chu, Taiwan).
"Planarization method" was invented by Yi-Ching Chen (Kaohsiung, Taiwan), Ching-Ling Lin (Kaohsiung, Taiwan) and Wen-An Liang (Tainan, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A planarization method includes the following steps. A silicon layer is deposited on a substrate, and a top surface of the silicon layer includes a lower portion and a bump portion protruding upwards from the lower portion. An ion bombardment etching process is performed to the silicon layer for reducing a surface step height of the silicon layer. The top surface of the silic...