Flip Chip Packaging Technique Application : Study of Silicon Wafer Substrate on Blue LED Assembling

• Main Authors: Chen Hsin-Kang, 陳新綱
• Other Authors: Lee Xuan Neng
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/22324698385252765502

碩士 === 輔仁大學 === 化學系 === 90 === Abstract LED has the following unique characteristics: high luminance efficiency, extraordinary long lifetime and fast response speed. In addition to applying in sort of electronic utilities, in nowadays, the application of LED can be noticed in traffic signs, outdoors display boards and communication devices. This study is based on the application of different assembling technologies in the promotion of LED’s brightness without altering LED’s epitaxy structure. The material of Blue LED chip is GaN whose epitaxy layer must be attached on sapphire wafer. LED chip front side is coated with a thin transparent metal electrode and two wire-bonding pads. These metal films on luminance area decrease the brightness. Since the sapphire substrate is transparent and both bonding pads are at the same side, here we design a silicon substrate module with flip-chip assembling concept to make luminance direction from chip backside. Thus we can have higher brightness LED module with the same power and LED structure. Also in this study, we test the silicon substrate’s electrical characteristics before and after combining with Blue LED chip. We measure multiple metal films’ strength by needle-shearing test and improve the strength and outlook of metal layers with different etching and deposition techniques. The main purpose for this study is to establish a well-organized production procedure and ensure device quality in a stable state to fulfill the practical production demand and application.