High-throughput electron-beam lithography with a raster-scanned, variably shaped beam

A raster-shaped beam writing strategy has been tested on a prototype 50 keV electron-beam lithography workstation. The test stand was constructed to prove the raster-shaped beam concept by exposing patterns at full throughput over small areas. Patterns are composed in a raster-scanned array of variably shaped flashes at 100 MHz flash rate, with 0.9 muA full beam current, and 2200 A/cm(2) current density using a thermal field emission source. Writing speed is independent of resist sensitivity and pattern complexity. By comparison, a typical variably shaped beam system with a LaB6 source would have a current density of 10-30 A/cm(2) and a flash rate of 2 - 10 MHz, depending on resist sensitivity and deflection settling time. (C) 2001 American Vacuum Society.