Improved power conversion efficiency in n-MoS2/AlN/p-Si (SIS) heterojunction based solar cells

In the present work, MoS2/Si (n-p) and MoS2/AlN/Si (Semiconductor-Insulator-Semiconductor (SIS)) heterojunctions based solar cells have been fabricated by depositing ultrathin layers of MoS2 and AlN on p-type Si substrate by DC magnetron sputtering technique. The SIS heterojunction exhibits higher current and large threshold voltage as compared to conventional p-n junction in Current-Voltage (I-V) characteristics. It suggests that the tunnelling of charge carriers can be a better transport mechanism for solar cell applications. With the AlN layer insertion, the power conversion efficiency of the device increases from 2.92% to 3.53%. The insertion of ultrathin insulating AlN layer in between the n-MoS2/p-Si heterojunction lowers the static charge transfer and makes more effective tuning of the Fermi level. The obtained results demonstrate a novel route for the fabrication of efficient photovoltaic devices for next-generation energy harvesting applications. (C) 2020 Elsevier B.V. All rights reserved.