CNT-based enhanced GaAs/InAs multiple quantum well solar cell

This work presents the optimized model and results of numerical simulations and analysis of CNT-based GaAs/InAs multiple quantum wells (from 5 to 70 QWs) GaAs solar cell. These QWs are found to extend the absorption edge beyond that of the GaAs band gap. Further, with the introduction of the wide band gap InGaP back surface field (BSF) layer in the model, efficiency is enhanced due to the reflection of unabsorbed photons from the bottom of the device back into the quantum well. The proposed model uses a heterogeneous CNT layer as top semi-transparent electrode. It is observed that this CNT top layer with lower sheet resistance and better light transmission can significantly improve the overall efficiency. Our optimized cell with 35 number 25 nm quantum well structure with 100 nm CNT top layer with sheet resistance of 128 Ω/□ is found to increase the efficiency up to 34.12