Electronic transport properties of polycrystalline silicon films depositedon ceramic substrates

In this paper we first present our results on growth of silicon onto silico n oxide and ceramic (alumina, mullite) substrates in three chemical vapor d eposition (CVD) reactors using chlorosilanes as precursor gases. The effect of operational parameters (substrate temperature and gas concentration) on growth rate and grain size were analyzed using scanning electron microscop y (SEM) technique. We show that deposition rates up to 5 mu m/min can be re ached. Furthermore, preferential(up to 80%) (220) oriented structure with g rain size ranging from 0.5 to 10 mu m can be generated for a 10 mu m thick Si film. In the second part we report on electronic properties of the depos ited poly-Si films through the layer resistivity, open-circuit voltage of p hotovoltaic devices, minority carrier diffusion length and spectral respons e data. We show that the grain size and the post-hydrogenation treatment af fect mostly the open-circuit voltage and weakly the spectral response. (C) 1999 Elsevier Science B.V. All rights reserved.