Brightness enhancement in pulsed-operated perovskite light-emitting transistors

Perovskite light-emitting field-effect transistors (PeLEFETs) provide a versatile device architecture to control transport and electroluminescence properties of hybrid perovskites, enabling injection of high charge carrier density and spatial control of the radiative recombination zone. Ionic screening and organic cation polarization effects typical of metal-halide perovskites, however, critically affect PeLEFET efficiency and reliability. In this work, we demonstrate a new device operation mode based on high-frequency modulation of the applied voltages, which allows significant reduction of ionic drift/screening in methylammonium lead iodide light-emitting transistors. In optimized top contact PeLEFETs, AC operation results in brighter and more uniform electroluminescence compared to DC-driven devices, whereas high-frequency modulation enables electroluminescence emission up to room temperature.Ministry of Education (MOE)National Research Foundation (NRF)The research was supported by the Singapore Ministry of Education (grant nos. MOE2016-T1-1-164 and MOE2011- T3-1-005) and the Singapore National Research Foundation (CRP award no. NRF-CRP14-2014-03)