Process integration issues in thin-film photovoltaics and their impact on future research directions

Abstract

Thin‐film device processing relies heavily on the integration of a variety of materials and a wide array of process steps. These include in some instances, the integration of ‘wet’ (chemical etching) and ‘dry’ (deposition and plasma etching) process steps. As substrates are stepped through the process sequence, there are many surfaces that ultimately become interfaces that can have a dramatic impact on ultimate device performance. However, in thin‐film R&D, these issues are not always carefully considered. This can have severe consequences when adapting an R&D‐developed process into pilot production, and finally, into manufacturing. In this paper, we explore the impact of process integration issues on the microstructure and device performance for three prominent photovoltaic thin‐film technologies (cadmium telluride, copper indium diselenide, and amorphous silicon). We also consider the impact of these concepts on future research directions in thin‐film photovoltaics. Published in 2000 by John Wiley & Sons, Ltd.

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