US Patent Issued to TAIWAN SEMICONDUCTOR MANUFACTURING on Feb. 17 for "Overlay marks for reducing effect of bottom layer asymmetry" (Taiwanese Inventors)

ALEXANDRIA, Va., Feb. 17 -- United States Patent no. 12,554,206, issued on Feb. 17, was assigned to TAIWAN SEMICONDUCTOR MANUFACTURING Co. LTD. (Hsinchu, Taiwan).

"Overlay marks for reducing effect of bottom layer asymmetry" was invented by Hung-Chih Hsieh (Hsinchu, Taiwan), Kai-Hsiung Chen (New Taipei, Taiwan) and Po-Chung Cheng (Chiayi County, Taiwan).

According to the abstract* released by the U.S. Patent & Trademark Office: "Methods of fabricating and using an overlay mark are provided. In some embodiments, the overlay mark includes an upper layer and a lower layer disposed below the upper layer. The lower layer includes a first plurality of compound gratings extending in a first direction and disposed in a first region of the overlay...