Pattern definition employing prism-based deep ultraviolet lithography

Abstract

Interferometric lithography provides a simple, cost-effective technique for the fabrication of large-area submicrometre periodic features. Biprism-based interferometric lithography employing a deep ultraviolet (DUV) light source is investigated for defining periodic patterns in large area with sub-500 nm pitch and sub-200 nm resolution. Collimated DUV light along with biprism with an angle of 30.4° was employed to fabricate grating lines using single exposure and square lattice features using double-exposure technique. Pyramidal prism was also employed to fabricate holes in square lattice using single exposure. Pitch size of around 410 nm and minimum feature size of 190 nm were realised employing this technique.