US Patent Issued to HOYA on Nov. 11 for "Mask blank substrate, substrate with multilayer reflective film, reflective mask blank, reflective mask, and method of manufacturing semiconductor device" (Japanese Inventors)

ALEXANDRIA, Va., Nov. 11 -- United States Patent no. 12,468,220, issued on Nov. 11, was assigned to HOYA Corp. (Tokyo).

"Mask blank substrate, substrate with multilayer reflective film, reflective mask blank, reflective mask, and method of manufacturing semiconductor device" was invented by Tatsuya Sasaki (Tokyo) and Masaru Tanabe (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "A mask blank substrate includes two opposing main surfaces, has a glass material containing SiO2 and TiO2, and has a first region in one main surface side. The first region is a region within a square including a center portion in the one main surface and which is a region extending from the one main surface toward the other mai...