Estimation of self-healing effects in halide perovskite based rectifying device structures via deep-level transient spectroscopy

TL;DR

This study investigates defect energy levels and self-healing effects in halide perovskite devices under radiation stress using deep-level transient spectroscopy, revealing defect formation and annealing behaviors relevant for device stability.

Contribution

The paper provides a detailed analysis of defect evolution and self-healing mechanisms in halide perovskite devices subjected to radiation, using advanced spectroscopic techniques.

Findings

Electron irradiation induces deep anti-site defect states with 0.83 eV activation energy.

Increased radiation dose raises defect concentration, which can be annealed during temperature sweep.

Insights into defect behavior and self-healing in halide perovskite devices under external stress.

Abstract

The defect-activity in halide perovskites remains a critical factor for the application in optoelectronics. The imperfections (vacancies, anti-sites, interstitials) formed in the lattice of the halide perovskites were considered as a main origin for the corrosion of the interfaces and decomposition process under external stress. At the same time, the self-healing effect was reported as one of the features for the devices based on halide perovskites, which manifests in the recovery of device performance under specific conditions. Such processes require a detailed analysis for the quantitative analysis of the defect parameters. In this work, we used Admittance and Optical Deep-level Transient spectroscopy to determine the evolution of the defect energy levels in the simplified rectifying device architecture based on CH3NH3PbBr3 after consecutive accumulation of the absorbed radiation dose (fast electrons, 5 MeV). We found that electron beam irradiation induces the formation of the deep states of anti-sites PbBr with activation energy of 0.83 eV. Increase of the absorbed radiation dose up to 1.5 Mrad resulted in a critical raise of 0.83 eV defect concentration, which can be effectively annealed during the temperature sweep. The changes in the defect parameters after different values of the absorbed radiation dose were analyzed and discussed. The current work provides new insights for the self-healing process of halide perovskite-based devices under hard external stress, revealing the important specifics of the defect behavior.