Impedance spectroscopy for quantum dot light-emitting diodes

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 dC/dV 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.

Preface to Special Issue on Advanced Optoelectronic and Electronic Devices toward Future Displays

“…These areas include organic light emitting diode (OLED) as well as QLED based on quantum dots. The paper by Bryan Tam et al describes a new way to produce high resolution OLED using close space sublimation [4] . The paper by Xiangwei Qu and Xiaowei Sun [5] , as well as the paper by Depeng Li et al [6] review and report the development in quantum dot based QLEDs.…”