Advances in continuous, in-line processing of stable CdS/CdTe devices

A continuous, in-line process suitable for high throughput manufacturing of CdS/CdTe photovoltaic devices has been demonstrated. Utilizing this process, devices with efficiencies of 13% has been fabricated with a low iron soda lime glass (3″×3″) with ant-reflection coatings. The process has been extended to large area devices (16″ ×16″ substrate size). After CdCl2 treatment, devices showed Voc ≫ 700 mV and Jsc ≫ 20 mA/cm². This performance is similar to the performance of small area devices which showed good stability. Also we have employed Spectroscopic Ellipsometry (SE) as a nondestructive tool to characterize CdS/CdTe heterojunction specifically studying the effects of chemical treatment on the optical properties of the thin-film layers.