Microcrystalline silicon thin-film solar cells prepared at low temperature using PECVD

The low-temperature deposition of μc-Si:H has been found to be effective to suppress the formation of oxygen-related donors that cause a reduction in open-circuit voltage (V_oc) due to shunt leakage. We demonstrate the improvement of V_oc by lowering the deposition temperature down to 140°C. A high efficiency of 8.9% was obtained using an Aasahi-U substrate. Furthermore, by optimizing textured structures on ZnO transparent conductive oxide substrates, an efficiency of 9.4% was obtained. In addition, relatively high efficiency of 8.1% was achieved using VHF (60 MHz) plasma at a deposition rate of 12 Å s⁻¹. Thus, this low-temperature deposition technique for μc-Si:H is promising for obtaining both high efficiency and high-rate deposition technique for μc-Si:H solar cells.