Analysis and modeling of the radiation response of III-V space solar cells

An analysis of the basic mechanisms for the radiation response of III-V solar cells for space applications is presented. At lower radiation fluence levels, minority carrier diffusion length degradation is the primary degradation mechanism. At higher fluences, carrier removal is the dominant mechanism. To exemplify these damage mechanisms, response of an InP solar cell under 3 MeV proton irradiation is presented and analyzed. This paper also presents a model by which the response of a solar cell to irradiation by a particle spectrum can be accurately predicted from a single characteristic degradation curve. This model, based on displacement damage dose (Dd), allows accurate prediction of the performance of a solar cell in the radiation environment of a specific Earth orbit. In addition, it is shown how this model can be used to reduce the complex particle spectrum of an Earth orbit to a single value of Dd. (author)