METHOD TO PRODUCE DIFFRACTION GRATING Russian patent published in 2010 - IPC G02B5/18 

FIELD: physics.

SUBSTANCE: proposed method consists in preliminary treatment of initial plate in degreasing solution to form grating surface and preset structure elements thereon with the help of photolithography processes, and fixation of preset structure on carrier. Note here that said initial plate is made from molybdenum-rhenium alloy with thickness not over 0.035 mcm. After said preliminary treatment by degreasing solution, it is additionally subjected to treatment by solution of the following composition, wt %: hydrogen nitrate - 35-40, hydrogen dioxide - 30-35, ferric chloride - (111) 10-15, water making the rest. Treatment is effected at room temperature for 0.1-0.2 minutes with subsequent annealing in hydrogen atmosphere at 980-1000°C for 25-30 minutes in mandrel made from molybdenum. Formation of diffraction grating preset structure elements by photolithography processes is performed at other claimed conditions of said processes.

EFFECT: higher mechanical strength, accuracy, reproducibility and yield of suitable plates.

1 tbl, 1 dwg