Electron Beam Lithography of HSQ and PMMA Resists and Importance of their Properties to Link the Nano World to the Micro World

In this work we investigated the properties of HSQ and PMMA resists focusing on contrast and line width for ebeam lithography (EBL) application. HSQ was found to be a good candidate to have desired line widths but the contrast we obtained was less than it was for PMMA. Since the fluorine based plasma does not have high selectivity over exposed HSQ, we propose a PMMA/HSQ bi-layer resist stack as a hard mask to etch Si selectively. Using this technique, 50nm deep Si fins may be patterned.