Sub-Half-Micron Silicon Pattern Generation by Electron Beam Direct Writing on Polysilane Films

Abstract

Polysilane thin films have been grown by the glow discharge of SiH4 at a substrate temperature of -90°C or -110°C. The bonded hydrogen in the film is effused by electron beam (EB) irradiation, resulting in three-dimensional Si network formation. The unirradiated part of the polysilane is easily oxidized in air at room temperature, while the EB-irradiated region is hardly oxidized. This enables us to fabricate the fine silicon pattern with a width of about 0.1 µm embedded in SiO2. Such a fine silicon line obtained by EB direct writing can be crystallized by 800°C annealing in an N2 atmosphere for 2 h.