Electrostatic Damage Influenced by Bottom Gate-Like Effects in Flexible Organic Light-Emitting Diodes

• Published in: IEEE electron device letters Vol. 44; no. 10; p. 1
• Main Authors: Xiong, Zhiyong, Gu, Jiachang, Xiang, Dongxu
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bottom Gate-Like Effects; Damage; Electrostatic Damage; Electrostatic discharges; Electrostatics; Flexible OLEDs; Hydrogen; Hydrogen plasma; Interface Modification; Interface stability; Light emitting diodes; Logic gates; Organic light emitting diodes; Polyimides; Semiconductor devices; Thin film transistors; Threshold voltage
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2023.3303951

Electrostatic damage has been shown to be a common phenomenon in display applications especially in flexible organic light-emitting diodes (OLEDs). Herein, to analyze the damage formation process and the internal physical mechanism, a bottom gate-like effects model based on the accumulation of negative charges under a thin film transistor (TFT) channel was proposed. The results after electro-static discharge (ESD) test substantiated that the threshold voltage (Vth) was positively shifted and the subthreshold swing (SS) was increased, which caused the luminance variation of flexible OLEDs. Furthermore, these changes can also be reproduced by applying a voltage under the samples, which is an analogy to the bottom gate-like effects. In order to alleviate the electrostatic damage influences, hydrogen plasma was adopted as an interface modification method to enhance the stability of TFT under electro-static discharge conditions. The research opens the possibility of considering more relationship between the display performance and the microscopic charge behaviors for their actual applications.