Optimization of Light Emitting Diode Processing Parameters Using Thermo-Ultrasonic Flip-Chip Bonding Technology

• Main Authors: Jr-da Huang, 黃智達
• Other Authors: Chung-feng Jeffrey Kuo
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/12377697772608678989

碩士 === 國立臺灣科技大學 === 高分子系 === 96 === The light emitting diode (LED), a new light source in the twenty-first century, contains many advantages, such as high efficiency, long lifespan, and bold structure. The technology for chip packing is the focal point to increase LED quality and performance. Flip-chip bonding, a kind of chip packing technology, allows produced chip to be lighter and smaller. Thermo-ultrasonic flip chip bonding is a way that directly joins gold pad and gold bump. The gold-gold connecting interface has better strength and electric reliability along with simple production process with no lead pollution. This kind of packaging also can be done in low pressure and low temperature with high accuracy and fine pitch. This study focuses on LED thermo-ultrasonic flip chip bonding process to find the multi-quality properties with the optimization of LED processing parameters. The process will be more complex as qualities have strong correlation to each other. With many different quality characteristics, we will have to determine the combination of processing factors to yield best performance. We first used the Taguchi orthogonal array table and then the principal component analysis to remove the relativity of each quality characteristics. We then used grey relational theory to obtain the best LED processing parameter and then used the back-propagation neural network and Levenberg-Marquardt algorithm to establish the LED Flip-Chip Bonding processing-quality predicting system. The error of the result is within 5%, indicating a high forecast capability.