Growth of polycrystalline silicon films on glass by high-temperature chemical vapour deposition

Covering glass substrates with polycrystalline Si films for electronic devices such as solar cells still presents a great challenge. In a two-step process, we first coat a novel high-temperature resistant glass substrate with a thin film of amorphous Si, which is then solid-phase crystallized at 600 degrees C. In the second step, atmospheric pressure chemical vapour deposition at 1000 degrees C serves to deposit a several micron thick light-absorbing film. The minority carrier diffusion length in our films correlates with the area weighted grain size determined by transmission electron microscopy. We obtain a hole mobility of 68 cm(2) V-1 s(-1) after hydrogen passivation and an electron diffusion length of 2 mu m.