Addressing band-edge-property spatial variations and localized-state carrier trapping and recombination in solar cell numerical modeling

TL;DR

This paper reviews and models how spatial variations in band-edge properties and localized defect states affect solar cell performance, emphasizing numerical methods to incorporate these effects for better device understanding and optimization.

Contribution

It introduces a numerical modeling approach that includes band-edge variations and localized defect states, enhancing the simulation accuracy of solar cell behavior.

Findings

Effective forces from band-edge variations are incorporated into models.

Localized states cause carrier trapping, field modification, and recombination.

Implementation demonstrated using AMPS simulation code.

Abstract

Conduction and valence band-edge-property variations with position as well as defects giving rise to localized states in the energy gap can play a significant role in determining solar cell performance. Understanding their effects on a device is necessary in interpreting complex experimental observations and in optimizing the performance of solar cells. In this overview, we include the effective forces arising from electron and hole band-edge-property variations with position in a numerical formulation of solar cell performance. Further we systematically catalogue and review a variety of localized states with different types and distributions, and include in our numerical transport model the carrier trapping, electric field modification, and recombination caused by these localized states. The successful implementation of the numerical modeling of band-edge-property variations and defect state effects is demonstrated using the methodology of the solar cell simulation code Analysis of Microelectronic and Photonic Structures (AMPS) and its derivatives.