Investigation of CSAR 62, a new resist for electron beam lithography

CSAR 62 is a new positive tone electron beam resist designed to have similar performance to ZEP520A in resolution, speed, and etch resistance. In this paper, the authors have used the resist to carry out high resolution electron beam lithography and as a mask for reactive ion etching on dielectrics, gallium arsenide, and silicon substrates coated with a 160 nm film of aluminum. Comparisons have been made between the results obtained using CSAR 62, ZEP520A, and polymethylmethacrylate. The authors conclude that CSAR 62 does demonstrate similar resolution, sensitivity, and etch resistance as ZEP520A but also gives rise to substantial resist residuals after development. These are almost entirely eliminated by using an alternative developer.