Nano-scale patterning using pyramidal prism based wavefront interference lithography

In this work we propose to fabricate nano-scale square lattice features using the principle of four wavefront interference employing a pyramidal prism. A UV laser of 266 nm wavelength was used to pattern features on thinned positive tone resist AZ 7220 using single exposure technique. It was demonstrated that features with sub 500 nm pitch size could be recorded using a pyramidal prism with edge angle of 30.4°. Holes with diameter around 187 nm in square symmetry with pitch of 414 nm were fabricated. The proposed setup is relatively simple, requiring minimum number of components.