A Novel Silicon-Dioxide Etching Process Employing Pulse-Modulated Electron-Beam-Excited Plasma

Abstract

We developed a novel silicon-dioxide (SiO2) etching process employing a pulse-modulated electron-beam-excited plasma (EBEP) and investigated its etching characteristics. The pulse-modulated EBEP was found to have an excellent potential for resolving problems such as the plasma-induced thermal damage on a photoresist film on a substrate and the nonuniformity of etching in a conventional EBEP. Furthermore, the anisotropic SiO2 etching at a high rate of 375 nm/min was successfully performed without any thermal damage to the photoresist film. The etching rate of the pulse-modulated EBEP was a few tens times higher than those of conventional etching processes without any additional bias power supply. As a result, the microfabrication on the end surface of the optical fiber was demonstrated.