An Innovative Parametric Optimization using Taguchi Method for Cu(In,Ga)(S,Se)2 Thin Film Solar Cell Device Simulation

Abstract

In this simulation study, Taguchi Method was used to investigate the influence of the absorber layer grading profile on the photovoltaic performance of CIGS solar cells. The work is simulation-based whereby the solar cell model was created and simulated using SCAPS-1d software. Four control factors have been chosen, such as the band gap minimum (E_g,min), the position of the band gap minimum (X_Eg,min), the band gap of the absorber layer towards the buffer layer (E_g,front), and the band gap of the absorber towards the back contact (E_g,rear). The aim is to find the most suitable combination of control factors that result in the most favorable outcomes for open circuit voltage (V_oc), short circuit current (J_sc) and fill factor (FF) over acceptor concentration ranging from 2.0x10¹⁴ to 2.0x10¹⁶ cm^-3 and donor concentration between 1.0 x10¹⁷ to 1.0x10¹⁹ cm^-3. The results show that the highest power conversion efficiency was achieved using a combination of high-level E_{g, min} with low-level X_{Eg, min}, middle-level E_{g, front} and high-level E_{g, rear}. The simulated device demonstrated an average efficiency of 22.08% with corresponding J_sc = 43.05 mA/cm², V_oc = 0.704 V and FF = 76.37. Confirmation test on the developed model from Taguchi Method demonstrates a robust characteristics on all outcomes against the realistic carrier concentration range mentioned above.