Low Defect, High Resolution, Sub-Micron Electron Beam Lithography Using Conventional, Commercial Resist Systems

摘要

The objective of the research was to develop techniques for sub-micron lithography with relatively high yield. Through variation in exposure technique and substrate, masks with 0.5 micron clear lines and chrome lines were consistently achieved with excellent line edge acuity and low defect density. Several exposure techniques were investigated. The optimal technique for the existing process conditions uses a low exposure current and a larger number of beam retraces. The higher retrace count proved to be more efficient in exposing the resist than the same overall dose with a smaller number of retrace counts. This exposure technique also seems to be most tolerant of variations in environmental conditions as well as variations in developer chemistry. Sub-micron geometries were written on 4,000 A, 3,000 A, and 2,000 A of resist, processed, and viewed under the scanning electron microscope.