Numerical simulation of a new heterostructure CIGS/GaSe solar cell system using SCAPS-1D software

The aim of this work is to study the photovoltaic performance of a solar cell based on GaSe materials using SCAPS-1D simulator. The novelty of this work consists in the use of GaSe lamellar as a buffer layer, this material has not been used at this part of solar cells before, which makes this new study interesting; we had also used a thin film (CIGS-P+), strongly doped type p as back surface field in order to obtain high performance. The solar cell is made up of two CIGS layers with different acceptors densities, one layer of Gallium selenide GaSe, and ITO anti-reflective layer. The role and impact of the CIGS-P+ layer as a back surface field on the performance of solar cells were investigated. To improve cell performance, the effects of thickness, carrier concentration, operating temperature, and resistors Rs and Rsh are explored. The carrier concentration as well as the thickness of the GaSe, CIGS absorber layer, and CIGS-P+ were shown to affect the cell's performance. The open circuit voltage of the simulated cell was increased to 309 mV after using CIGS-P+, the current density Jsc up to 32.61 mA/cm2, the Fill Factor FF up to 89.39%. After employing CIGS-P+ in a GaSe-based solar cell, an efficiency gains of roughly 10.06 % was recorded.