Electron-Beam-Induced Nucleation Centers and Selective Deposition of Thin Zinc Films

Abstract

Selective deposition of pure metal films was achieved successfully by combining electron-beam irradiation and subsequent vapor deposition. A thin layer of hydrocarbon was used as a beam-sensitive material. It was found that organic materials such as different kinds of hydrocarbons possess much higher sensitivities to electron-beam irradiation than the inorganic material. Nucleation centers were produced by e-beam irradiation at an electron dose density as low as 5×10-3 C/cm2. This value is at least three orders of magnitude lower than the value reported for inorganic material to date and allows high-speed or large-area processing. It was observed that the behavior of the deposition is kinetics controlled. Due to this mechanism, the size of the deposition area was found to always be smaller than that of the irradiating beam and it varied with the electron dose. It is expected that this mechanism may possibly reduce the back-scattered-electron effect and achieve a spatial resolution better than the beam-spot diameter.