LED芯片电流扩散与尺寸的仿真分析

Simulation Analysis of Current Spread of LED Chip

摘要:

LED芯片尺寸极大地影响着LED芯片内部电流密度分布，通过研究LED芯片尺寸与电流分布的关系，能帮助优化LED芯片设计，提升LED发光效率。本文从理论上讨论了LED芯片尺寸与电流分布的关系，并通过COMSOL MULTIPHYSICS软件研究了芯片尺寸对LED电流扩展能力的影响。仿真结果表明：大尺寸的LED芯片电流扩展能力相对较差，电流拥挤现象较为严重，电极周围区域电流密度显著高于其他区域，小尺寸电流密度分布较为均匀，但当LED芯片达到某一尺寸后，电流扩展能力变化趋于平稳。

Abstract:

Chip size of LED greatly affects the current density distribution inside the LED chip. By studying the relationship between chip size of LED and current density distribution, it can provide key reference for LED chip designing and optimizing. This paper theoretically discusses the relationship between LED chip size and current distribution, and simulating the effect of chip size on LED current spreading capability using COMSOL MULTIPHYSICS software. The simulation results show that the current expansion capability of the large-sized LED chip is relatively poor, the current crowding phenomenon is more serious than the small chip. The current density around the electrode is significantly higher than other regions in the large-sized chip. However, the small-sized current density distribution is relatively uniform. The simulation also shows that the current expansion capability tends to be stable when the LED chip reaches a certain size.