Plasma deposited and evaporated thin resists for template fabrication

Abstract:
In this paper, we demonstrate electron beam lithography at energies ranging from 2 keV to 100 keV, on sub-100 nm thick resists. Such uniform and thin electron beam sensitive films can be deposited by evaporation or by plasma deposition. Two examples of such resists are studied, QSR-5 which is a negative sterol based evaporated resist and QPR-P50 which is a positive PECVD deposited fluoropolymer resist. AFM measurements demonstrate surface roughness smaller then 3 nm for QSR-5 and 0.7 nm for QPR-P50. In both cases, 50 nm features or better are patterned using electron beam lithography on a template blank consisting of a glass substrate, coated with a 10 nm thick Cr transfer layer and a resist layer. LER (3 σ) is measured to be less then 8% for 50 nm wide lines in QSR-5 and of approx. 10% for 50 nm wide lines in QPR-P50.