Since 1976 when Carlson and Wronski demonstrated the amorphous silicon (a-Si) solar cell, it has been on a focus of attention as a low cost solar cell. Aided by the accelerative promotion of the Sunshine Project in Japan, the DOE plan in the U.S, and various countries' plans, numerous research breakthroughs have led to rapid improvement in conversion efficiency. Recently, conversion efficiency of more than 11% was achieved for single-junction structures, and furthermore, more than 13% for multi-junction structures.
Since the world's first electronic calculator powered by an a-Si solar cell was put on the market in 1980, consumer electronics and stand-alone systems have been continuously growing in number and in types.
This paper reports on recent development in a-Si solar cells. Highly efficient fabrication technologies for a-Si solar cells are mentioned, and the present status of the industrialization of a-Si solar cells is described.