Microcrystalline silicon films deposited by hot-wire CVD for solar cells on low-temperature substrate

The structural and electronic properties of undoped microcrystalline silicon (μc-Si:H) thin films prepared by hot-wire chemical vapor deposition (HWCVD) at various hydrogen dilutions have been studied. UV–visible ellipsometry was used to quantify the crystalline, amorphous and void fractions, and to determine the presence, or otherwise, of an amorphous incubation layer. Diffusion-induced time-resolved microwave conductivity measurements showed that the electronic transport along the growth direction is notably improved for samples prepared by a double-dilution process, where the H2 dilution is decreased as a function of the deposition time. These results should be useful for further HWCVD μc-Si:H solar cells.