Optimization of the In$_{0.3}$Ga$_{0.7}$As-layer thickness in a triple-junction In$_{0.3}$Ga$_{0.7}$As/GaAs/In$_{0.5}$Ga$_{0.5}$P solar cell

The optimum absorbing-layer thickness in the bottom In$_{0.3}$Ga$_{0.7}$As subcell of a triple-junction In$_{0.3}$Ga$_{0.7}$As/GaAs/In$_{0.5}$Ga$_{0.5}$P solar cell is sought for using the Sentaurus TCAD software package as a factor of the minority charge-carrier lifetime in this layer. The lifetime is set in the range from 17 ps to 53 ns. The calculation results show that the optimum thickness varies from 0.9 to 7.5 $\mu$m. In addition, the contribution of the bottom In$_{0.3}$Ga$_{0.7}$As subcell to the efficiency of this triple-junction solar cell is estimated at various lifetime values. Its value varies from 1 to 7%.