JPS6459884A - Forming of shift type diffraction grating pattern - Google Patents

Abstract

PURPOSE:To form an accurate and uniform shift diffraction grating pattern by utilizing a resist which is not sensitized by light wavelength to be used when performing patterning of phase shift layer as a resist layer when performing interference exposure of resist layer on substrate through a phase shift layer of a patterned specified thickness. CONSTITUTION:A positive resist layer 2 for far ultraviolet rays to record a diffraction grating pattern, a polyvinyl alcohol layer 3 as a buffer layer, and a phase shift layer 4 are formed on a substrate 1. Then, patterning is performed only to a phase shift layer using normal photolightography technique so that only the part to be shifted may remain. By providing asymmetrical inciding angle two fluxes of light interference path light from an obtained phase shift layer pattern 4a and a PVA layer 3 (2 fluxes of light: 6a, 6b), recording is performed by shifting the phase of pattern of certain part of the shift layer 4 if the positive resist layer 2 is exposed to light through the polyvinyl alcohol layer 3 which is the buffer layer each. Then, the phase shift layer pattern 4a and the polyvinyl alcohol layer 3 which is the buffer layer are eliminated. Then, the pattern is developed and is transferred to the substrate 1. A resist pattern 2a is shifted symmetrically at the position A in Figure.