Investigation of Electrode Electrochemical Reactions in CH3NH3PbBr3 Perovskite Single-Crystal Field-Effect Transistors
Authors: Wang, JZ; Senanayak, SP; Liu, J; Hu, YY; Shi, YJ; Li, ZL; Zhang, CX; Yang, BY; Jiang, LF; Di, DW; Ievlev, AV; Ovchinnikova, OS; Ding, T; Deng, HX; Tang, LM; Guo, YL; Wang, JP; Xiao, K; Venkateshvaran, D; Jiang, L; Zhu, DB; Sirringhaus, HN
ADVANCED MATERIALS
Volume: 31 Issue: 35 Published: AUG 2019 Early Access: JULY 2019 Language: English Document type: Article
DOI: 10.1002/adma.201902618
Abstract:
Optoelectronic devices based on metal halide perovskites, including solar cells and light-emitting diodes, have attracted tremendous research attention globally in the last decade. Due to their potential to achieve high carrier mobilities, organic-inorganic hybrid perovskite materials can enable high-performance, solution-processed field-effect transistors (FETs) for next-generation, low-cost, flexible electronic circuits and displays. However, the performance of perovskite FETs is hampered predominantly by device instabilities, whose origin remains poorly understood. Here, perovskite single-crystal FETs based on methylammonium lead bromide are studied and device instabilities due to electrochemical reactions at the interface between the perovskite and gold source-drain top contacts are investigated. Despite forming the contacts by a gentle, soft lamination method, evidence is found that even at such "ideal" interfaces, a defective, intermixed layer is formed at the interface upon biasing of the device. Using a bottom-contact, bottom-gate architecture, it is shown that it is possible to minimize such a reaction through a chemical modification of the electrodes, and this enables fabrication of perovskite single-crystal FETs with high mobility of up to approximate to 15 cm(2) V-1 s(-1) at 80 K. This work addresses one of the key challenges toward the realization of high-performance solution-processed perovskite FETs.
Full Text: https://onlinelibrary.wiley.com/doi/full/10.1002/adma.201902618