PROCESS PARAMETER VARIATION STUDY OF PHOTORESIST IMAGING

Abstract

IC fabrication needs have encouraged studies on various sub-processes to improve upon the device density that can be fabricated. The device dimensions have gone down upto 0.2 to 0.4 micron. The most important sub-process which play a determining ole in reducing the device dimensions, is photoresist imaging. In this work, a study of parameter variations on photoresist imaging has been conducted. The effects of exposure time, development time, softbaking, post exposure baking etc. on photo resist pattern have been observed and discussed. A process latitude using Scanning Electron Microscope (SEM) for the Vistak-H positive resist has also been determined which provides very useful information for selecting a resist system for a particular application