Patent ID: 6134008
Filing Date: 2000-10-17
Classification: G03F

Abstract:
An aligner, comprising:means for emitting exposure light from a light source;means for separating said exposure light into first exposure light and second exposure light;means for irradiating a first phase shift mask with said first exposure light;means for irradiating a second phase shift mask with said second exposure light;means for causing first transmission light transmitted through said first phase shift mask with second transmission light transmitted through said second phase shift mask to interfere with each other, thereby combining the first and second transmission light into interference transmission light; andmeans for irradiating photoresist on a film to be etched formed on a semiconductor substrate with said interference transmission light, whereinsaid first phase shift mask includes a plurality of first strip shaped transmission regions spaced apart and extending in a first direction, and a plurality of first strip shaped light shielding regions between said plurality of first strip shaped transmission regions,in said plurality of strip-shaped transmission regions, a phase non-shift transmission region which transmits the first phase non-shift transmission light with its phase unchanged and a phase shift transmission region shifting the phase of the transmitted first phase shift transmission light from the phase of said first phase non-shift transmission light are repetitively and alternately provided,said second phase shift mask includes a plurality of second strip-shaped transmission regions spaced apart and extending in a second direction crossing said first direction, and a plurality of second strip-shaped light shielding regions between said plurality of second strip-shaped transmission regions, andin said plurality of second strip-shaped transmission regions, a phase non-shift transmission region transmitting second phase non-shift transmission light with its phase unchanged and a phase shift transmission region shifting the phase of transmitted second phase shift transmission light from the phase of said phase non-shift transmission light are repetitively and alternately provided.