Recent Progress in CdTe Solar Cell Research at SCI

Research at Solar Cells, Inc. is focused on developing processes which will lead to high volume and low cost manufacturing of solar cells and to increase the performance of our present technology. The process research has focused on developing vapor transport deposition of the semiconductors, eliminating wet chemistry steps while minimizing the chloride treatment time, forming a low-loss backcontact using only dry processing, and an improved interconnection technique. The performance improvement work has focused on the increase of the photocurrent by a combination of more transparent glass substrates and a thinner CdS window layer deposited on an i-SnO2 buffer layer. SCI record 13.0% 1 cm2 devices have been fabricated using these techniques. Stability monitoring continues and showsminimal degradation for over 20,000 hours of continuous light soak at 0.8 sun illumination.