Development efforts on silicon solar cells

This report presents a summary of the major results from the silicon high-concentration solar cell program at Stanford University from the period 1983--1990. Following a detailed design study, efforts were focused upon experimental verification of the modeled results that predicted 28% efficiencies for a new 500X concentrator solar cell design. A history of the research progress is given detailing the critical experiments that enabled the demonstration of 19.6% cells in 1983, then subsequent improvements culminating in efficiencies over 28% by 1987. In addition to laboratory efficiency improvements, the report details advances in the understanding of the fundamental device physics and modeling of silicon solar cell operation. The latter stages of the program included the development of module-ready cells in large quantity for the EPRI prototype 500X concentrator modules. Several of these 48-cell modules are currently in the field under test.