Patent ID: 9442230
Filing Date: 2016-09-13
CPC Classification: G02B,G03F

Claim Text:
1. A method of manufacturing a sub-wavelength extreme ultraviolet metal transmission grating, comprising: forming a silicon nitride self-supporting film window on a back surface of a silicon-based substrate having both surfaces polished; spin-coating a silicon nitride film on a front surface of the silicon-based substrate with an electron beam resist (HSQ); performing electron beam direct writing exposure on the HSQ, and then performing developing and fixing to form a plurality of grating line patterns having a duty cycle of 1:3 and a ring pattern surrounding the grating line patterns; depositing a chrome material on the front surface of the silicon-based substrate through magnetron sputtering as a light-blocking layer for the grating line patterns and the ring pattern; removing the chrome material inside the ring pattern so that only the chrome material outside the ring pattern is retained as a absorber of scattering light; growing a gold material on the front surface of the silicon-based substrate through atomic layer deposition; and removing the gold material on the chrome material outside the ring pattern, between the grating line patterns, and on the grating line patterns so that only the gold material on sidewalls of the grating line patterns is retained.