Study on packaging structure of high power multi-chip LED

LED lighting is referenced as the forth generation green lighting with the great advantages of low power consumption, high luminous efficiency and long service life. Thermal management is one of the most important aspects of successful LED systems design. In this paper, a novel packaging structure for high power multi-chip LED was proposed and investigated. Firstly, Chip on Board (COB) technology was applied in the LED package structure to increase the capacity of heat dissipation, and remote phosphor was employed to increase luminous efficiency as well. Secondly, numerous grooves were made on every fin of heat sink to improve thermal performance, and rectangular pits were dug at the copper wiring layer and dielectric layer of MCPCB for mounting LED chip to reduce thermal resistance. Then, heat distribution of whole packaging structure was simulated by ANSYS software, and the simulation result shows that the maximum temperature is 64.444°C on LED chip, which was verified by theoretical calculation. Finally, the main factors of affecting LED output performance, including layout of chip, way of wire bonding, and heat sink were taken into consideration, and the LED package structure and size were optimized with the application of Design of Experiment (DOE) and statistical analysis.