Elucidating contact-limited temperature dependence of charge transport in 2D tin halide perovskite field-effect transistors

Abstract

Two-dimensional (2D) tin halide perovskites are gaining attention for their potential in high-performance field-effect transistors (FETs) due to their ease of processibility and high mobility. However, their complex charge transport mechanism remains poorly understood with no definitive transport models established. While temperature-dependent mobility analysis is a proven method for constructing accurate charge transport models in a given material system, systematic temperature dependence studies in prototypical 2D tin perovskites, PEA2SnI4, have been rarely reported. Here, we investigate the temperature-dependent transport properties of PEA2SnI4 in FETs, employing contact resistance analyses to decouple intrinsic channel mobility from contact resistance contributions. Our results reveal that the extracted mobility values are significantly contact-limited, particularly at lower temperatures, leading to substantial deviations in apparent mobility trends. By correcting for contact resistance, we establish that the intrinsic mobility of PEA2SnI4 remains nearly temperature-independent from 100 K to 300 K. Our results clearly address the critical need to account for contact effects in determining carrier mobility of perovskite materials within the community, offering a refined framework for accurately evaluating and enhancing the performance of perovskite-based electronic devices.