Patent ID: 6392792
Filing Date: 2002-05-21
Classification: B82Y,G02B,G03F,G21K,Y10S

Abstract:
A method of fabricating an EUV diffraction element comprising:(a) forming an etch stack comprising alternating layers of first and second materials on a substrate surface where the two materials can provide relative etch selectivity; (b) creating a relief profile in the etch stack wherein the relief profile has a defined contour and the relief profile has at least three levels wherein each level is formed by: (i) forming a resist film on top of the stack; (ii) exposing one or more patterned regions and developing to uncover one or more regions of the stack; (iii) etching one layer of the stack where uncovered of resist; and (iv) repeating steps (i) through (iii) at least once up to the number of stack layers available; and (c) depositing a multilayer reflection film over the relief profile wherein the film has an outer contour that substantially matches that of the relief profile.