ALEXANDRIA, Va., Sept. 17 -- United States Patent no. 12,416,855, issued on Sept. 16, was assigned to United Microelectronics Corp. (Hsinchu, Taiwan).
"Photomask structure" was invented by Chia-Chen Sun (Kaohsiung, Taiwan), Song-Yi Lin (Tainan, Taiwan) and En-Chiuan Liou (Tainan, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A photomask structure including a layout pattern and at least one assist pattern is provided. The layout pattern includes corners. The assist pattern wraps at least one of the corners. There is a gap between the edge of the layout pattern and the assist pattern."
The patent was filed on July 31, 2022, under Application No. 17/878,026.
*For further information, including images,...