ALEXANDRIA, Va., Nov. 18 -- United States Patent no. 12,474,628, issued on Nov. 18, was assigned to SHIN-ETSU CHEMICAL Co. LTD. (Tokyo).
"Reflective mask blank and method for manufacturing reflective mask" was invented by Takuro Kosaka (Niigata, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A reflective mask blank has a substrate 10; a multilayer reflective film 20 that is provided on the substrate 10 and reflects exposure light; a protective film 50 including a metal oxide film 51 provided on the multilayer reflective film 20; and an absorber film 70 that is provided on the protective film 50 and absorbs exposure light. The multilayer reflective film 20 is configured such that a Mo layer and a Si lay...