Optimization of (p–i₁–i₂–n)a-Si:H solar cell interfaces: an integrated AFORS-HET and Taguchi design of experiments study

This study aims to optimize the physical design parameters of the front interface in (p–i₁–i₂–n)a-Si:H thin-film solar cells. The research focuses on identifying the optimal combination of acceptor doping concentration (N_A), bandgap (E_g) and p-layer thickness (d_p) under varying front contact barrier potentials ( $φb0$φ_b0), which are independently examined through a parametric analysis to maximize conversion efficiency.

The research uses an integrated framework combining numerical simulation via Automat for Simulation of Heterostructures (AFORS-HET) with the Taguchi statistical Design of Experiments. A Taguchi L₉ orthogonal array was used to systematically explore parameter interactions with minimal simulation runs. Main Effect Analysis and Analysis of Variance were subsequently applied to evaluate the sensitivity and contribution of each parameter to the cell’s efficiency.

The results identify N_A as the most dominant factor, contributing 78.27% to the variation in efficiency, followed by d_p (16.80%) and E_g (3.01%). The optimal configuration (N_A= 1.0 × 10¹⁹ cm⁻³, E_g at 1.85 eV and d_p at 9 nm) yielded a confirmed conversion efficiency of 9.82%. The study demonstrates that coupling numerical modeling with Taguchi-based optimization significantly enhances computational efficiency.

This work presents a systematic integration of AFORS-HET with a Taguchi statistical framework, combined with a parametric evaluation of front contact barrier potentials, to investigate performance optimization in (p–i₁–i₂–n)a-Si:H structures. This physics-informed framework provides a cost-effective and adaptable methodology for developing high-performance next-generation photovoltaic technologies.