High Growth Rate for Slow Scanning in Electron-Beam-Induced Deposition

Abstract

Electron-beam-induced deposition using WF6 gas was used to directly fabricate conductive wires. In view of the gas supply, repeated fast electron beam scanning had been thought to be more efficient than single slow scanning. The results, however, proved otherwise. There are three possible reasons: (1) less beam drift, (2) rise in temperature of beam exposure region, and (3) numerous secondary electrons generated from the inclined growth front of a wire. The first possibility is clearly negated by an experiment where beam drift is negligible. The second possibility is thought to be low because the rise in temperature is estimated to be less than 1° C. Simulation of wire growth using the string model where the secondary electron effect is taken into account gives good agreement with the experimental results. Detailed observation of fabricated wires using an atomic force microscope supports the idea that the high growth rate is most likely caused by the increase in numbers of secondary electrons generated.