ELECTRON PROJECTION LITHOGRAPHY

The basic study of EPL has been done under the name of SCALPEL^® by AT&T (Lucent Technologies, then Agere Systems) from the beginning of 1990s and the name of PREVAIL for electron optical system by the joint work of IBM and Nikon. The features of EPL are larger sub-field size and higher acceleration voltage of electron for obtaining usable higher electrical current on wafer and a wide deflection width for obtaining higher throughput.

EPL system has such features as a large sub-field size, large deflection width, high electrical current, high acceleration voltage and thin Si stencil mask. EPL has been considered as one of the promising technologies for hp65nm node and beyond.

Nikon has developed the first EPL tool and it was delivered to Selete in Japan. The tool has been used for EPL technology evaluation and process development in the pilot line of Selete. This chapter describes the various aspects of EPL technology from basic concept through technology evaluation and future extendibility.