Thermal Analysis and Performance Optimization of Quantum Dots in LEDs by Microsphere Model

Abstract

Quantum dots (QDs) have aroused intensive research interest because of their unique optical properties and capability in the fabrication of high-performance light-emitting diodes (LEDs). However, the optical performance of the QDs is strongly affected by their intrinsic thermal sensitivity as well as the dispersion state in LEDs, thus demanding more accurate thermal control of the QDs in the LED package to promote performance optimization. In this article, a microsphere model is developed to study the thermal behavior of the QDs in the LED package by considering their monodispersion and heat accumulation. The utilization of the model provides the simulated temperature as well as the heat distribution of the QDs more in line with the experimental results, achieving an average error of only 0.01%-2%. Further study based on the microsphere model reveals that a layered package structure can offer better heat control and light uniformity for the QDs-based LEDs (QD-LEDs). The optimized package realizes a maximum of 12.5 °C temperature reduction for QDs than the conventional structure and the valid operation power for QD-LEDs to operate at 80 °C is promoted by 25%.