Dry Development Rinse Process for Ultimate Resolution Improvement via Pattern Collapse mitigation

摘要

Pattern collapse currently limits the achievable resolution of the highest resolving EUV photoresists available. The causes of pattern collapse include the surface tension of the rinse liquid and the shrinkage of the resist pattern during the drying step. If these collapse mechanisms can be successfully mitigated with process approaches that do not require changes to the resist itself, the ultimate resolution of existing EUV resists can be improved. Described here is a dry development rinse process, applicable to existing EUV photoresists, which prevents pattern collapse to both improve ultimate resolution and the process window of currently resolvable features. Reducing the burden of collapse prevention on the resist also allows improvements in line width roughness (LWR) and cross section profile and provides additional degrees of freedom for future resist design.