Optimization of Parameter Design of Cu Wire Bonding Process in IC Assembly Industry

• Main Authors: Yeh, Cheng-Jung, 葉振榮
• Other Authors: Li, Rong-Kwei
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/73832824975569143868

博士 === 國立交通大學 === 工業工程與管理學系 === 99 === The yield of IC (Integrated Circuit) assembly manufacturing is dependent on wire bonding. Recently, the semiconductor industry demands smaller IC designs and higher performance requirements. As such, bonding wires must be stronger, finer, and more solid. The cost of gold is continuously appreciating, and this has become a key issue in IC assembly and design. Copper wire bonding is an alternative solution to this problem. It is expected to be superior over Au wires in terms of cost, quality, and fine-pitch bonding pad design. To obtain the best wire bonding quality, this study discussed some important issues on wire bonding quality and employed Taguchi methods in optimizing the Cu wire bonding process. With Cu wire bonding technology, the production yield increased from 98.5% to 99.3 % and brought approximately USD 0.7 million in savings. Meanwhile, a combined approach of neural networks and genetic algorithms after applying the Taguchi methods are used to optimize the Cu wire bonding process. Using this new approach, the production yield increased from 98.5% to 99.65%, resulting in approximately USD 1.16 million in savings. In this study, the response belongs to multiple objectives. In order to judge the wire bonding quality, desirability function is used to transfer multiple objectives to single response.