Impact of reduced resist thickness on deep ultraviolet lithography

Potential capabilities of a thinner resist process are verified from both points of view - lithography and etch processes. The experimental results for lines and spaces indicate that a larger gain in process window could absolutely go along with reduced resist thickness. It is found that the thinner resist process could successfully improve not only the optical proximity effect in lithography processes but also the microloading effect in etch processes. It is also demonstrated that an application of the thinner resist process would be useful to further extend advantages of higher numerical aperture exposure systems. The thinner resist process is found to be effective to improve the process window of contact holes. Moreover, a novel pattern transfer process could be demonstrated using the practical limit of resolution capability up to k(1)=0.4. (C) 1996 American Vacuum Society.