Status of Silicon Solar Cell Radiation Damage

Radiation damage in solar cells has been extensively studied in the past five years by many investigators who-have described radiation induced effects in a host of parameters, such as, for example, efficiency of energy conversion, maximum power point, short-circuit current, open circuit voltage, minority-carrier-diffusion length, spectral response, junction capacitance, dark current, and curve power factor. To give an added dimension to these many results, many varied light sources have been used (on nonsatellite experiments), including carbon arcs, xenon, arcs, and tungsten bulbs, often in combination with water or optical filters. Of course, sunlight at ground level, aircraft, and balloon altitudes has received a share of attention. in addition, solar cells have been fabricated from silicon of a wide range of resistivities, controlled dopants and uncontrolled impurities, with impurity-gradients producing internal electric fields, and with different types of surface coatings.