25 August 1987 Chemical Factors Affecting Npr Performance
Author Affiliations +
NPR, a material consisting of a novolac resin blended with poly(2-methyl-l-pentene sulfone) (PMPS), is an attractive positive electron beam resist. However, it exhibited a number of problems during processing. For example after the development step, NPR patterns were surrounded by a halo due to resist thickness differences in the region next to the exposed areas. Also, a thin residual film appeared in the developed regions. A study of these problems showed that immiscibility between the two NPR components was responsible for many of the results. Also, Fourier Transform Infra Red Spectroscopy showed that a low molecular weight PMPS, [n] - 20 cm3/g, considerably improved compatibility and reduced the defects mentioned above. For this reason a study of PMPS molecular parameters by Gel Permeation Chromatography (GPC), light scattering and intrinsic viscosity was undertaken. This study related the molecular variables to synthetic conditions and a reproducible synthesis was established. A new NPR system was prepared with 9% low molecular weight sulfone polymer. This resist exhibits good film quality after development and displays a sensitivity of 8pC/cm2 with excellent (0.25μm) resolution.
© (1987) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
R. G. Tarascon, R. G. Tarascon, J. Frackoviak, J. Frackoviak, E. Reichmanis, E. Reichmanis, L. F. Thompson, L. F. Thompson, } "Chemical Factors Affecting Npr Performance", Proc. SPIE 0771, Advances in Resist Technology and Processing IV, (25 August 1987); doi: 10.1117/12.940308; https://doi.org/10.1117/12.940308

Back to Top