End-to-end predictive modeling of silicon solar cell performance: From process recipe to device simulation

We demonstrate the use of end-to-end predictive modeling to optimize silicon solar cell fabrication processes. Coupled continuum models for boron, phosphorus, iron, and oxygen are used to predict the distribution of electronically active defects. The models include point defect-mediated diffusion of boron and phosphorus from solid sources (e.g., POCl₃) at both the emitter and back surface field. Interactions between iron and boron, boron and oxygen, and phosphorus and vacancies are modeled. From the resulting dopant and defect distributions, carrier lifetimes are computed and, along with the solar cell structure, are passed to a device simulation. We find a competing effect between lifetime-enhancing iron segregation to the boron-rich region and lifetime-degrading BO₂ complex formation. Guided by modeling results, we suggest strategies to restore device performance in the presence of iron contamination and moderate oxygen concentrations, demonstrating the utility of an “end-to-end” modeling framework.