Effect of Gas Dilution Ratios and Substrate Temperature on the Structural Transition of a-Si/μc-Si Thin-Film Solar Cell Using PECVD

Thin films of mixed amorphous/ microcrystalline-phases have been researched during the last decade, for manufacturing silicon solar cells. In this work the Plasma Enhanced Chemical Vapor Deposition PECVD process parameters; namely dilution ratios and substrate temperature, were controlled to build i-layer at low dilution ratios with moderate substrate temperatures. In this work an intrinsic layer was deposited on Indium Tin Oxide ITO glass by PECVD technique, with different dilution ratios of silane in hydrogen to study the transition from amorphous to microcrystalline phase. The Si:H thin film was evaluated by field emission scanning electron microscopy, x-ray diffraction and atomic force microscopy. The structural transition between a-Si:H to μc-Si:H achieved at dilution ratio 13.3 and substrate temperature 250°C with surface roughness 22.5 nm.