A Novel Packaging Structure for High Power LED Based on Chip on Heat-Sink Method

Abstract

Recently, LED lighting receives extensive attention and is put in practice in many respects with the great advantages of low power consumption, high luminous efficiency and long service life. However, it is confronted with lots of problems such as light failure and short service life caused by high temperature of LED chip. So the thermal management is one of the most important aspects of successful LED systems design. In this paper, firstly, a novel packaging structure with excellent capacity of heat dissipation for high power LED which is based on Chip on Heat-sink (COH) method was proposed and investigated. Secondly, some holes were dug in the Printed Circuit Board (PCB) according to the design of heat-sink structure to realize electrical connection between chips and PCB. Then, the heat distribution for three kinds of package structure was simulated by using the software ANSYS, respectively. The simulation result shows that heat dissipation potential of the packaging structure based on COH method is best of all. After that, the main dimension parameters of LED package structure were optimized with the application of Design of Experiment (DOE) and statistical analysis. Finally, samples of the packaging structure based on COH were made successfully. The parameters of thermal properties of the samples were tested by The Thermal Transient Tester (T3ster) in order to verify the accuracy of t simulation results.