Micro-Column Arrays for Nanolithography

摘要

The research program has made substantial advances in areas relevant to the useof low energy electron beams and microfabricated electron beam columns for high resolution lithography. The first was the development of novel cold field emission sources. Focused ion beam milling was used to demonstrate the effectiveness of self-shielding to enhance electron emission on a variety of cold field electron sources as well as fabrication of apertures in silicon membranes. Titanium nitride thin films have been characterized for use as coatings on tungsten field emitters. These films provide robust, inert, stable emission surfaces capable of milliampere emission currents without requiring high temperature processing. The films can be coated on a variety of base emitter structures. The second area of research at Cornell focused on low energy electron beam lithography processes compatible with high throughput microcolumn electron beam lithography. Two new resist systems were evaluated, and systems demonstrated the target sensitivity of 1 micro-coulomb per square centimeter needed to achieve high throughput. The final area involved the development of pattern transfer processes for silicon device fabrication. Both resist systems were used as an etch mask to etch bulk silicon using low energy chlorine ions from an electron cyclotron plasma etch system.