Patent ID: 6569581
Filing Date: 2003-05-27
Classification: G03F

Abstract:
A phase shifting mask for use in lithographic processing of semiconductor substrates comprising:a mask substrate substantially transparent to the energy beam used in the lithographic processing; a patterned phase shifting layer disposed on the mask substrate and having openings therein exposing the mask substrate, the patterned phase shifting layer being comprised of a material of differing composition than the mask substrate and of thickness sufficient to shift the phase of an energy beam passing through the thickness of the patterned layer and the mask substrate by 180 degrees, compared to the phase of the energy beam passing through the phase shifting layer openings and the mask substrate; and a patterned layer of a material substantially opaque to the energy beam having a portion disposed on the mask substrate, through the openings in the phase shifting layer, and having a portion disposed on the patterned phase shifting mask layer.