INFLUENCE OF TOTAL GAS FLOW RATE ON THE PERFORMANCE OF HIGH RATE DEPOSITION MICROCRYSTALLINE SILICON SOLAR CELLS

摘要

In this paper, the influence of total gas flow rate (SiH_4+H_2) on solar cell performance and quality ofmicrocrystalline silicon films deposited at high rates was studied. High rate deposition of microcrystalline siliconwas conducted by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) process with ahigh power and high pressure. Under the above conditions, it was found that the total gas flow rate became animportant parameter in determining solar cell performance. With increasing total gas flow rate from 100sccm to 300-500sccm, short circuit current increased by ～50%, due to a remarkable improvement in quantum efficiencies at thevisible and near infrared. As a result, the maximum efficiency of 8.11% had been achieved at 8.5A/s for i-layerdeposition. The improved performance of the solar cells was contributed to the thickness of amorphous siliconincubation layer decreased with the total gas flow rate increasing.