Selection of Alternatives for Improving Recycle Process of C/D Wafers

• Main Authors: Chia-Shien Chien, 簡嘉賢
• Other Authors: Muh-Cherng Wu
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/87176830161420370106

碩士 === 國立交通大學 === 工業工程與管理系 === 91 === lection of Alternatives for Improving Recycle Processes of C/D Wafers Student：Chia-Shien Chien Advisor：Dr. Muh-Cherng Wu Institute of Industrial Engineering National Chiao Tung University ABSTRACT Control/dummy (C/D) wafers are used to measure the process quality in semiconductor manufacturing. C/D wafers are reusable by recycle cleaning and can be downgraded to the downstream processes. Previous studies on C/D wafers aimed to reduce the use of C/D wafers by making appropriate downgrade decisions. Yet, the yield improvement in the recycle process C/D wafers is seldom explored. This research formulates a decision problem and proposes solution methods for the selecting the yield improvement alternatives in the C/D recycle processes. The decision problem is to determine the yield improvement targets for each recycle process in order to minimize the use of C/D wafers, under a given budget for yield improvement. The two solution methods involve a genetic algorithm and a marginal allocation algorithm. The two methods yield same solutions but the marginal allocation method is good in requiring much less computation. key word：control wafer, dummy wafer, recycle cleaning, genetic algorithm, marginal allocation