Submicron DUV lithography using second-harmonic light of copper vapor laser

In order to study the feasibility of submicron lithography using second-harmonic light (SHL) at wavelength of 255.3 nm of copper vapor laser (CVL), a 1:1 catadioptric projection lens and an illumination system are designed and constructed. A resolution of 0.7 micrometers line/space patterns is produced in AZ1350J resist, which reveals that the SHL of CVL can be used as an illumination source in submicron lithography.