Irradiation Damage Simulation Research Of Triple-junction GaAs Solar Cells Based On Different Bottom Cell

Efficient energy supply can promote the rapid development of aerospace industry.Group III-V multi-junction solar cells represented by Ga As solar cells have high conversion efficiency and become the main energy supply for space flight devices.Due to the harsh space environment,especially the charged particles in space,the solar cell will be damaged,which will affect the execution of space missions.Therefore,this paper conducts irradiation simulation research on lattice matched GaInP/（In）Ga As/Ge triple-junction solar cell,inverted metamorphic GaInP/Ga As/In_0.3GaAs triple-junction solar cell and flexible inverted metamorphic GaInP/Ga As/In_0.3Ga As triple-junction solar cell.The main research results are as follows:1.The electrical and optical properties of 1 MeV electrons at different fluences of 1×10¹⁴e/cm~2,5×10¹⁴e/cm~2,1×10¹⁵e/cm~2were investigated for lattice matched GaInP/（In）Ga As/Ge triple-junction solar cell.The experimental characterization and APSYS simulation were carried out to establish the damage model of the solar cell performance.The greater degradation of electrical performance near the defect level of E_c-0.96 e V for（In）Ga As sub-cell.In terms of external quantum efficiency（EQE）,Ge bottom cell can absorb sunlight in a longer wavelength range due to their lower band gap.After irradiation,the top cell is the most resistant to irradiation,and the EQE of the middle cell and the bottom cell are attenuated to different degrees.2.By using the method of experiment and simulation,the electrical and optical properties of 1 Me V electrons at different fluences of 1×10¹⁴e/cm~2,5×10¹⁴e/cm~2,1×10¹⁵e/cm~2for inverted metamorphic GaInP/Ga As/In_0.3Ga As triple-junction solar cell were studied.The fitted volt-ampere characteristic curve is obtained by setting the minority carrier lifetime of the SRH recombination in the sub-junction solar cell.Before irradiation,the solar cell performance corresponding to the AM1.5D,AM1.5G and AM0 solar spectra increased with increasing spectral energy.In terms of external quantum efficiency,the degradation of 1 Me V electron irradiation on the long wavelength band of the In_0.3Ga As sub-cell is more obvious under the AM0 solar spectrum.3.14 Me V neutron with the fluence of 7.3×10¹¹n/cm~2,3.7×10¹²n/cm~2,7.3×10¹²n/cm~2were carried out on the flexible inverted metamorphic GaInP/Ga As/In_0.3Ga As triple-junction solar cell.The electrical properties and optical properties are measured by experimental test and simulation calculations.Before irradiation,the conversion efficiency of the flexible solar cell can reach 29%.With the increase of the irradiation fluence,the optical and electrical properties of the solar cell degrade to varying degrees,which leads to the degradation of the overall performance of the solar cell and affects its working efficiency.