We report on the development of a low-cost, thin-film electrodeposited cadmium telluride solar cell. The most efficient cell developed to date had an efficiency of 8.6% (under AM1 illumination), an open circuit voltage of 0.723 V, a short circuit current density of 18.7 mA/cm2, and a fill factor of 0.64. The cell uses a Schottky barrier rectifying junction at the front surface and a cadmium ohmic contact at the back. Passivation of the top surface improves the photovoltaic properties of the rectifying junction.

Due to its basic optical, electronic, and chemical properties, CdTe can become the base material for high-efficiency, low-cost thin film solar cells using robust, high-throughput manufacturing techniques. CdTe films suited for photovoltaic energy conversion have been produced by nine different processes. Using n-type CdS as a window-partner, solar cells of up to 16% efficiency have been made in the laboratory. Presently five industrial enterprises are striving to master low cost production processes and integrated modules have been delivered in sizes up to 60 × 120 cm2, showing efficiencies up to 9%. Stability, health, and environmental issues will not limit the commercial potential of the final product. The technology shows high promise for achieving cost levels of $0.5/Wp at 15% efficiency. In order to achieve this goal, scientists will have to develop a more detailed understanding of defect chemistry and device operation of cells, and engineers will have to develop methods for high-throughput manufacturing.

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