Large grain polycrystalline silicon via chemical vapor deposition

Abstract

Large grain polycrystalline Si films were grown by chemical vapor deposition (CVD) onto TiB2 substrates using the SiCl4–H2 reagent system. A statistically designed processing study was used to correlate the film growth rate, crystallographic orientation, and grain size with deposition temperature, the SiCl4 : H2 ratio, and the level of B doping. Each process variable influenced grain size with temperature having the dominant effect. Grains as large as 15 to 20 μm were achieved for a coating thickness of about 50 μm.