I-V characteristics of InGaP/GaAs solar cell with the presence of a back surface field and a tunnel junction

Abstract

The high efficiency solar cells are based on semi conductor technology. A tandem solar cell is simulated using the solar simulator Tcad silvaco. In this work, we aim to model the dual junction InGaP/GaAs solar cell with a single back surface field (BSF) to extract the main influence of this layer as well as the tunnel junction on the characteristics I-V. The considered InGaP/GaAs cell is composed of two BSFs InAlAsP BSF for the InGaP cell and AlGaAs BSF for the GaAs cell. The top cell (InGaP) and the bottom cell (GaAs are separated by an InGaP/InGaP tunnel junction (TJ) with the same doping concentration for both the emitter and the base. In a first stage, the InGaP\GaAs cell is simulated without both BSFs, then without the tunnel junction. We noticed an efficiency η of 17.80% and 10.98% respectively. Finally; the InGaP/GaAs cell is simulated with both BSFs and the tunnel junction. We have obtained an I-V characteristics with an optimum conversion efficiency η=34.44%, an opencircuit voltage (VOC) of 2.62V and a short circuit current density (JSC) 14.49mA/cm2. The simulation respects the standard conditions AM1.5G illumination and a temperature of 300K.