CVD silicon film growth on powder substrates using an inline optical system

Abstract

This paper presents the results achieved with an inline optical chemical vapor deposition (CVD) system operating at atmospheric pressure and at low temperatures (<600° C). Using silane as the gaseous precursor, microcrystalline silicon layers were grown on compressed silicon micrometric powder substrates, moving at constant speed, and crossing three hot deposition regions several times. Microcrystalline silicon (µc-Si) ribbon samples measuring up to 25×70 mm were obtained with growth rates (GR) varying from 13 to 53 µm/min. Grain size of silicon powder has a great influence in GR. It was observed that using lower grain size powders as substrates, higher GR were obtained. Also, it was observed that for the larger grain size powders used, after deposition the silicon films grown were stuck to the quartz substrate holder and could not be removed pristine.