Ionizing Radiation Effects in Inversion Layer Silicon Solar Cells

Ionizing irradiation experiments on a new inversion layer solar cell have been carried out to determine its potential for space applications. A scanning electron microscope was used as a source of low energy (2-12 keV) electrons in doses up to 1014 e/cm2. Phototopographic scanning and C-V analysis were used to determine the effects of the radiation on the Si02-Si system. The electron irradiation results are validated by comparison with those of a conventional X-ray experiment. The operation, fabrication and electrical characteristics of the cell are also discussed. Large increases in both the oxide charge and surface state density were observed, but little change occurred in the cells´ output characteristics below 105 rads (Si). A drop-off in power at higher doses is explained in terms of surface recombination and series resistance increases. The results of isochronal and UV annealing experiments on these effects are also presented. The cells are concluded to have potential for use in space.