(472e) A New Thin Film Heterojunction Structure and Fabrication Process: Dual Backcontact CdS/CdTe Photovoltaics

Three-dimensionally structured solar cells seek to improve upon the efficiency and cost of planar devices. For the CdS/CdTe system, published 3D geometries have not yet achieved these goals, not surprising given the much longer history of research in planar devices. We propose a new geometry and process that could accelerate progress. Specifically we : (1) model the performance of devices with dual back contacts that move the CdS layer behind the CdTe and eliminate the front contact; (2) describe processing via inexpensive, scalable electrodeposition on microscale patterned insulating substrates; and (3) present the performance of some early devices. The processes and test bed geometries are amenable to an array of deposition techniques for fabrication and measurements of three dimensionally structured absorbers, contact materials and photovoltaic devices.