Hydrogenated Silicon Thin Film and Solar Cell Prepared by Electron Cyclotron Resonance Chemical Vapor Deposition Method

Abstract

Hydrogenated silicon thin film was deposited on glass substrate using the electron cyclotron resonance chemical vapour deposition (ECR-CVD) system. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to measure the film properties. It showed that higher deposition rate (>2nm/sec) and lower microstructure parameter (20%<R*<30%) could be achieved with increasing input power and decreasing hydrogen dilution ratio (H2/SiH4). In addition, p-type and n-type hydrogenated amorphous silicon thin films were grown using SiH4/Ar/H2/B2H6 or PH3 gases. Hall mobility decreased with increasing the doping gas flow rate. The carrier concentration exhibited an entirely converse behavior. With increasing the doping gas flow rate, the concentrations increased and the highest values of 5.2×1019 cm-3 (3.9×1019 cm-3) at H2/B2H6 (H2/PH3) of ~20 for p-type (n-type) hydrogenated amorphous Si thin films were achieved. These films are suitable for the amorphous Si thin film solar cell.