PHOTOVOLTAIC PROPERTIES OF THE CdS/CdTe HETEROJUNCTION SOLAR CELLS BEFORE AND AFTER PROTON IRRADIATION

摘要

In this work we report the experimental results of high-energy proton irradiations of 3 MeV and fluency of 3x1014protons/cm2on CdS/CdTe heterojunction solar cells. The photovoltaic cells were developed on ITO coated optical glass substrates, by conventional thermal vacuum evaporation technique. The CdS/CdTe is given a post deposition CdCl2 heat treatment which enables grain enhancement, reduces the defect density in the films, promotes the interdiffusion of the CdTe and CdS layers and thereby improves solar cell efficiency. The effects of irradiation were studied by investigating the changes in the electrical and optical properties of the cells. It was found that proton irradiation in the above mentioned conditions results mainly in the introduction of defects at the CdS/CdTe interface. From the I-V characteristics in fourth quadrant, at illumination in A.M. 1.5 conditions, measured before and after proton irradiation, the typical parameters as photoelement (short-circuit current, open-circuit voltage, fill factor, power conversion efficiency), were determined, before and after proton irradiation