The Study Of Electrical Property Degradation Of GaAs/Ge Solar Cells By Electron And Proton Co-Irradiation

On the basis of ground-based simulation for space proton and electron co-irradiation, the degradation in electrical property of GaAs/Ge solar cells applied in spacecrafts was studied in this paper.In the simulation experiment of proton and electron co-irradiation, the energy of two types of particle was fixed at 100KeV, the maximum fluence of electron was up to 1×1016cm-2 and the one of proton was up to 1×10¹²cm^-2. In order to study the different irradiation effect to GaAs/Ge solar cells between proton and electron, we did three types of irradiation experiment which were electron after proton, proton after electron and two types of particle co-irradiation. By the measurement of I-V characteristic curve, spectral response, optical reflectance ratio, PL, X-ray double-crystal diffraction, IR, electrical-chemistry C-V and Hall effect et al, we studied the change of inner-structure and property of cells, got the reason why property degrades induced by different irradiation types and different fluence of particles.According to the software simulation of 100KeV proton and electron irradiation by SRIM 2003 and Casino V2.42, we found the incident depth of 100KeV proton in materials is about 0.71μm, produce the most seriously damage at the end of their path. The depth of 100KeV incident electron is very deep which can arrive at Ge substrate. By the theoretical formula, we deduced and got the main reason why the Isc degrades and explained the damage effect of different irradiation types to the inner structure and property of cell materials by analyzing the process which incident particles interact with materials.