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Using diborane as doping gas, p-doped μc-Si:H layers are deposited by using the plasma enhanced chemical vapour deposition (PECVD) technology. The effects of deposition pressure and plasma power on the growth and the properties of μc-Si:H layers are investigated. The results show that the deposition rate, the electrical and the structural properties are all strongly dependent on deposition pressure and plasma power. Boron-doped μc-Si:H films with a dark conductivity as high as 1.42 Ω−1cm−1 and a crystallinity of above 50% are obtained. With this p-layer, μc-Si:H solar cells are fabricated. In addition, the mechanism for the effects of deposition pressure and plasma power on the growth and the properties of boron-doped μc-Si:H layers is discussed.

Cu2ZnSnS4 (CZTS) films are successfully prepared by co-electrodeposition in aqueous ionic solution and sulfurized in elemental sulfur vapor ambient at 400 °C for 30 min using nitrogen as the protective gas. It is found that the CZTS film synthesized at Cu/(Zn+Sn)=0.71 has a kesterite structure, a bandgap of about 1.51 eV, and an absorption coefficient of the order of 104 cm−1. This indicates that the co-electrodeposition method with aqueous ionic solution is a viable process for the growth of CZTS films for application in photovoltaic devices.

This paper reports that a series of silver oxide (AgxO) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 °C and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP). The AgxO films deposited apparently show a structural evolution from cubic biphased (AgO + Ag2O) to cubic single-phased (Ag2O), and to biphased (Ag2O + AgO) structure. Notably, the cubic single-phased Ag2O film is deposited at the SP = 105 W and an AgO phase with (220) orientation discerned in the AgxO films deposited using the SP > 105 W. The transmissivity and reflectivity of the AgxO films in transparent region decrease with the increase the SP, whereas the absorptivity inversely increases with the increase of the SP. These results may be due to the structural evolution and the increasing film thickness. A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP.

The structural un-uniformity of μc-Si:H films prepared using a very high frequency plasma-enhanced chemical vapour deposition method has been investigated by Raman spectroscopy, spectroscopic ellipsometer and atomic force microscopy. It was found that the formation of amorphous incubation layer was caused by the back diffusion of SiH4 and the amorphous induction of glass surface during the initial ignition process, and growth of the incubation layer can be suppressed and uniform μc-Si:H phase is generated by the application of delayed initial SiH4 density and silane profiling methods.