Thermodynamic simulation and analysis of metal bumps in flip-chip micro-LED packaging

Abstract

Thermal compression bonding provides a good solution for the packaging of micro-LED chips, greatly increases the resolution of micro-led, and can achieve higher density integration and better display effect. In order to study the thermomechanical reliability and display stability of micro-LED devices under thermal cycling load and working power load, this paper first explains the limitation of thermal expansion coefficient (CTE) mismatch on the size of flip chip devices by mathematical method, and proposes a low temperature indium bump flip chip bonding technology which can overcome this defect. Then, the finite element model is established to study the influence of different metal bump materials on the reliability of micro-LED devices under thermal cycling load, and the display stability is analyzed combined with the wavelength drift characteristics of micro-LED devices.