US Patent Issued to HOYA on Sept. 9 for "Reflective mask blank, reflective mask, and method for manufacturing semiconductor device" (Japanese Inventors)

ALEXANDRIA, Va., Sept. 10 -- United States Patent no. 12,411,402, issued on Sept. 9, was assigned to HOYA Corp. (Tokyo).

"Reflective mask blank, reflective mask, and method for manufacturing semiconductor device" was invented by Yohei Ikebe (Tokyo) and Osamu Nozawa (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "Provided is a reflective mask blank comprising a phase shift film having a small change in the phase difference and/or reflectance of the phase shift film even in a case where the film thickness of the phase shift film changes.A reflective mask blank comprises a multilayer reflective film and a phase shift film in this order on a main surface of a substrate. The phase shift film comprises a low...