INDUSTRIALIZATION OF a-Si SOLAR CELLS

The industrialization of amorphous Si (a-Si) solar cells has been made possible by an accumulation of basic physics research in the field of a-Si by a number of researchers. A new fabrication process in which p, i, and n layers are deposited in consecutive, separated reaction chambers has been developed. In this process, high-quality a-Si films are produced, because undesirable mixing of dopants is prevented. An integrated a-Si solar cell module in which several a-Si solar cells are connected in series has also been developed, which can generate a high voltage from one substrate. The mass production of this type of a-Si cell module has already begun for use in consumer applications. The theoretical limit efficiency and the energy payback period of p-i-n a-Si solar cells have been calculated. In order to apply the a-Si solar cell to a power source, experimental a-Si solar cell panels were produced. A 2-kW class demonstration plant consisting of these panels was constructed for the development of a power generating system and for the life test