ISSN: 1945-7553
CODEN: JTEVAB
Published Online: 1 September 2012
Page Count: 7

Precision Tool Condition Monitoring for Grinding Wheel in IC Manufacturing of Silicon Wafer

Hsu, Ya-Chen
Dept. of Business Administration, Yuanpei Univ., Hsinchu,

Pearn, W. L.
Dept. of Industrial Engineering and Management, National Chiao Tung Univ., Hsinchu,

Chuang, Ya-Fei
Dept. of Industrial Engineering and Management, National Chiao Tung Univ., Hsinchu,

(Received 3 December 2011; accepted 13 April 2012)

Abstract

In integrated circuit (IC) manufacturing industries, wafer grinding is an important step because it improves wafer flatness and thickness. The diamond-grinding wheel used for grinding the wafers is expensive. Inevitably, the diamond-grinding wheel wears gradually during the grinding process, and the wafer surface is contaminated by grinding chips. Consequently, the fraction of defectives gradually becomes significant. In this situation, cost reduction is important for silicon wafer suppliers in the global market. Therefore, it is essential to monitor the grinding wheel in order to reduce the manufacturing cost and minimize the fraction of defectives. In this paper, we consider the grinding-wheel replacement problem in IC factories with the aim of determining the optimal replacement time for the grinding wheels. In order to maintain high wafer process quality and minimize the production cost, we propose a tool condition monitoring procedure for assessing the true capability at each time period of the grinding process and then find the optimal time for tool replacement. The procedure can be used practically for the silicon wafer manufacturing industry.

Keywords:
grinding wheel, process capability index, silicon wafer, tool condition monitoring

Paper ID: JTE104598
DOI: 10.1520/JTE104598
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