Impedance spectroscopy for quantum dot light-emitting diodes

• Published in: Journal of semiconductors Vol. 44; no. 9; pp. 91603 - 38
• Main Authors: Qu, Xiangwei, Sun, Xiaowei
• Format: Journal Article
• Language: English
• Published: Chinese Institute of Electronics 01.09.2023; Key Laboratory of Energy Conversion and Storage Technologies (Southern University of Science and Technology), Ministry of Education, and Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting, Southern University of Science and Technology, Shenzhen 518055, China; Institute of Nanoscience and Applications, and Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
• Subjects: charge dynamics; equivalent circuit model; impedance spectroscopy; quantum dot light-emitting diode; impedance spectroscopy; quantum dot light-emitting diode; equivalent circuit model; charge dynamics
• ISSN: 1674-4926; 2058-6140
• DOI: 10.1088/1674-4926/44/9/091603

Abstract Impedance spectroscopy has been increasingly employed in quantum dot light-emitting diodes (QLEDs) to investigate the charge dynamics and device physics. In this review, we introduce the mathematical basics of impedance spectroscopy that applied to QLEDs. In particular, we focus on the Nyquist plot, Mott−Schottky analysis, capacitance-frequency and capacitance-voltage characteristics, and the d C /d V measurement of the QLEDs. These impedance measurements can provide critical information on electrical parameters such as equivalent circuit models, characteristic time constants, charge injection and recombination points, and trap distribution of the QLEDs. However, this paper will also discuss the disadvantages and limitations of these measurements. Fundamentally, this review provides a deeper understanding of the device physics of QLEDs through the application of impedance spectroscopy, offering valuable insights into the analysis of performance loss and degradation mechanisms of QLEDs.