Device modeling approach and simulation of the effect of the ODC thin layer on bifacial solar cells based on CuInl-xGaxSe2 thin films absorbers

In this work, thin films of In2Se3, which are employed for bifacial CIGS solar cell applications, are grown onto coated soda lime glass (SLG) substrates using physical vapor deposition (PVD) technique. Their structural, optical, and electrical properties are also illustrated. In addition, the device of bifacial CIGS thin film solar cells is studied. To employ the one-dimensional modeling tool analysis of microelectronic and photonic structures, we use the simulator (AMPS-1D) to numerically analyze the performances of bifacial CIGS solar cells. We show the role of the formation of the ordered defect compound (ODC) layer between the buffer layer and the absorber part on the performance of the device. The obtained results show that this defect layer is important in the photovoltaic performance of CIGS device. To optimize the bifacial cells, the simulated results show that the optimal thickness of ODC and the defect density are in the ranges 400-600 nm and 1 x 10(14) - 10(15) cm(-3), respectively. Thus, the results indicate that the ODC had an optimal bandgap above 1.3 eV. The conversion efficiencies exceeding 16% and 14% were obtained with illumination from the front and back contacts, respectively.