Silicon solar cells for high concentration applications

The use of solar concentrators can significantly reduce the cost of solar energy conversion, provided that the photovoltaic cells can be operated at high efficiencies under high illumination conditions. This paper describes the design, fabrication, and results of testing a cell with interdigitated p⁺and n⁺fingers on the unilluminated side of the solar cell. This design significantly reduces the problems of series resistance, contact grid shadowing, and voltage saturation which limit the performance of conventionally designed solar cells at high illumination intensities. The performance of such a cell at illumination intensities up to 22 watts/cm²is also presented.