Perovskite light emitting transistors

• Main Author: Cheng, Bryan Wei Hao
• Other Authors: Cesare Soci
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Science::Physics::Optics and light
• Online Access: https://hdl.handle.net/10356/163104
• Institution: Nanyang Technological University

Perovskite light-emitting transistors (PeLETs) are unique devices that combine two key functions of optoelectronics: electrical switching and amplification with light emission. They also provide a versatile platform for charge transport and recombination of charge carriers study in hybrid organic-inorganic perovskites; and are emerging materials with outstanding physical and chemical properties. Unfortunately, PeLETs suffer from low brightness and environmental instability related to intrinsic material limitations, such as temperature-activated trapping, ionic motion and polarization effects, which limit device performance and stability at ambient conditions. In this work, we realized spin coated and thermally evaporated methylammonium lead iodide (MAPbI3) perovskite light-emitting transistors operated by a pulsed gate bias voltage. This new approach reduces ionic motion and polarization effects significantly within the perovskite layer. Thus, increasing n-type drain current and mobility by 3 orders of magnitude at room temperature. Furthermore, electroluminescence brightness increases by means of operating independent pulsing of drain and gate bias voltages by more than 4 times at 77 K compared to single DC pulsed operation. Improvement of PeLET transport properties and overall stability at room temperature under pulsed regime allows for effective studying of intrinsic electronic properties of hybrid perovskites.