Harnessing the Sun with Thin-Film Photovoltaics: Preprint

Photovoltaic (PV) technologies have a substantial role in meeting electric; power needs in the next century, especially with an expected competitive; position compared to conventional power-generation and other renewable-; energy technologies. Thin-film photovoltaic modules based on CdTe,; CuInSe2 or Si can potentially be produced by economical, high-volume; manufacturing techniques, dramaticallyreducing component cost.; However, the translation of laboratory thin-film technologies to first-time,; large-scale manufacturing has been much more difficult than expected.; This is due to the complexity of the processes involved for making large-; area PV modules at high rates and with high yields, and compounded by; the lack of a fundamental scientific and engineering base required to;properly engineer and operate manufacturing equipment. In this paper, we; discuss the need to develop diagnostics tools and associated predictive; models that quantitatively assess processing conditions and product; properties. Incorporation of the diagnostic sensors into both laboratory; reactors and manufacturing facilities will (1) underpin the development of; solar cells with improvedefficiency, and (2) accelerate the scale-up; process through intelligent process-control schemes. 'Next-generation'; high-performance (e.g., >25% conversion efficiency) thin-film PV; modules will also be assessed, along with critical issues associated with; their development.