Production of 20 A sec/sup -1/ a-Si alloys for use in solar cells

The engineering principles used to make >20-A-s/sup -1/ intrinsic layers of good-photovoltaic-quality amorphous silicon over large areas are addressed. Deposition equipment was designed and installed in a plasma-assisted CVD (chemical vapor deposition) roll-to-roll processor. Films were made in this machine with gas mixtures containing silane. Same-bandgap tandem solar cells using this material had 8.2% (average) to 8.6% (best cell) conversion efficiencies. >