Jason E. Dingle

Monolithic series-connected gallium arsenide converter development

The development of monolithic GaAs photovoltaic devices intended to convert light generated by a laser or other bright source to electricity is reported. The converters described can provide higher operating voltage than is possible using a single-junction converter, owing to the use of a monolithic circuit that forms a planar series-connected string of single-junction sub-cells. This planar monolithic circuit is arranged to deliver the desired voltage and current during operation at the maximum power point. A description is presented of two, six, and twelve-junction converters intended for illumination by a laser diode with a wavelength of 0.8 mu m. Design and characterization data are presented for optical power in the range of 100 mW to 1 W. The best conversion efficiency exceeds 50%.<<ETX>>

A review of indium phosphide space solar cell fabrication technology

A review of the status of InP cell efficiency and of approaches to the reduction of cell cost is presented. The use of heteroepitaxial techniques such as InP-on-GaAs and InP-on-Si is discussed along with the use of chemical and mechanical techniques for removal and recovery of the substrate. The efficiency ultimately obtainable with designs made possible by such an approach is calculated.<<ETX>>

Performance of high-temperature survivable gallium arsenide concentrator cells

A report is presented on the fabrication and testing of survivable GaAs/AlGaAs double-heterostructure concentrator cells intended for space operation. Air mass zero (AMO) efficiencies of over 22% at 25 suns have been obtained. These cells are designed to survive thermal excursions to temperatures exceeding 600 degrees C without significant change in efficiency. It is found that the change in conversion efficiency is less than 10%, even after 1 h at 650 degrees C, and that the decrease in efficiency is only about 10% after 25 min at 700 degrees C. The cells continue to function after enduring 820 degrees C for 25 min. Details of the testing are reported. >