Issues Upon Surface and Interface of Microcrystalline Silicon Thin Film as a Solar Cell Material

摘要

Photovoltaic devices are recognized as a prospective electricity source in the 21st century. Microcrystalline silicon has attained intense interest because of its application to stable, high-efficiency and low cost solar cells. The microcrystalline silicon is prepared by nonequilibrium processes at low temperatures. In this article, we review the low temperature growth of crystalline silicon including both the microcrystalline and homoepitaxial growth, which are dominated not only by surface reactions on the growing surface but also by gaseous phase reactions among electrons, source gases and radicals. A novel aspect in the nonequilibrium process is that the homogeneous termination on the surface promotes the crystal growth unlike the MBE case. We also demonstrate a successful application of the low temperature process to the manufacture of high efficiency solar cells.