Document Type : Research article


1 Department of Electrical and ICT, Faculty of Technical Engineering, Institute for Higher Education, ACECR, Khouzestan, IRAN.

2 Instrument and Control Engineer at Well Services of Iran (WSI).


This research designed and simulated CIGS/CIGS back-to-back solar cells using Silvaco-Atlas software. We considered CIGS absorbing layer thickness and sub-cells as critical parameters to optimize the performance of the CIGS/CIGS tandem solar cell. The research comparatively examined the effect of different electrode metals, such as molybdenum, aluminum, titanium, and silver, on the efficiency. The electrical parameters of the best CIGS/CIGS tandem solar cell configuration were a short-circuit current density (Jsc) of 15.65 mA/cm², an open-circuit voltage (Voc) of 1.86 V, a fill factor (FF) of 86.04%, and a conversion efficiency (η) of 27.12%. The optimal CIGS absorbing layer thickness of the top and bottom cells corresponding to the maximum conversion efficiency obtained were 0.17 and 6.3 μm, respectively. In contrast, the optimal thickness of the Cds layer was 0.04 µm. Silver had the best performance in connecting layers between several metals. The results can be used to develop low-cost and high-efficiency solar cells.

Graphical Abstract

Optimization CIGS/CIGS Tandem Solar Cells by Adjusting Layer Thickness Using Silvaco-TCAD



  • Design and simulation of CIGS/CIGS back-to-back solar cells using Silvaco-Atlas software
  • Optimizing the performance of the CIGS/CIGS tandem solar cell
  • Studying the effect of electrode metal and comparison of different materials