Solid-Phase Epitaxy of CVD Amorphous Si Film on Crystalline Si

Abstract

The authors demonstrate that CVD amorphous Si crystallizes epitaxially on a (100)Si substrate with furnace annealing at temperatures of 600°C or below. Cleaning the substrate surface and depositing amorphous film at a low temperature with a high deposition rate are essential to this procedure. After loading the substrate into a CVD reactor, the substrate surface is first etched with H₂ to remove native oxide at 1100°C, and then with HCl to prevent foreign atom adsorption up to a low deposition temperature of 550°C. The low temperature prevents microcrystallite formation, and the high deposition rate hinders foreign atom inclusion during deposition. With the appropriate cleaning and deposition conditions, the resultant epitaxial layer crystallinity has been proven to be good through Rutherford backscattering and reflection electron diffraction measurement.