Effects of Design, Manufacturing Processes, and Materials on High-power LED Performance

Since the first light-emitting diode (LED) was invented by Holonyak and Bevacqua in 1962, LEDs have made remarkable progress in the past few decades with the rapid development of epitaxy growth, chip design and manufacture, packaging structure, processes, and packaging materials. LEDs have superior characteristics such as high efficiency, small size, long life, low power consumption, and high reliability. The market for white LED is growing rapidly in various applications. It has been widely accepted that white LEDs will be the fourth illumination source to substitute the incandescent, fluorescent, and high-pressure sodium lamps. With the development of LED chip and packaging technologies, the efficiency of high power white LED will broaden the application markets of LEDs while changing the lighting concepts of our lives. In this talk, we will present some of our recent results on the effects of design, manufacturing processes, and materials on high-power LED performance in terms of manufacturing yield, failure modes, thermal and optical performance. Some other research efforts in WNLO/HUST will also be presented.
Dr. Sheng Liu is a ChangJiang Professor of Mechanical Engineering at Huazhong University of Science and Technology. He holds a dual appointment at Wuhan National Laboratory for Optoelectronics, and has served as tenured faculty at Wayne State University. He has over 21 years experience in LED/MEMS/IC packaging and extensive experience in consulting with many leading multi-national and Chinese companies. Liu was awarded the White House/NSF Presidential Faculty Fellowship in 1995, ASME Young Engineer Award in 1996, China NSFC Overseas Young Scientist in 1999, and IEEE CPMP Excellent Technical Achievement Award in 2009. He has been an associate editor for IEEE Trans. On Electronic Packaging Manufacturing since 1999, an associate editor of Journal of Frontiers of Optoelectronics since 2007, and associate editor of Chinese Journal of Sensors and Actuators since 2004. He obtained a Ph.D. from Stanford in 1992, and got MS and BS in flight vehicle design, Nanjing University of Aeronautics and Astronautics, and he had three years industrial experience in China and USA. He has filed more than 280 patents in China and the USA, and has published more than 500 technical articles in English.