Title :
Implementation challenges of a feedback control system for wafer fabrication
Author :
Yeh, C. Eugene ; Cheng, John C. ; Wong, Kwan
Author_Institution :
IBM Almaden Res. Center, San Jose, CA, USA
Abstract :
A real-time feedback control system is being developed in a wafer fabrication line at IBM´s San Jose plant. The goal of the system is to minimize the alignment drifts, and hence to increase wafer yields and chip quality, by automatically adjusting the set points of the exposure machines. The major challenges of implementing the feedback control system are: (1) no modification on the existing equipment, (2) minimum interruptions to the production operation, (3) asynchronous operations and communications of multiple computers, (4) computational algorithm of new set points, (5) large volume of data, (6) data grouping, and (7) data filtering. These challenges and the methods taken to address them are discussed
Keywords :
computer integrated manufacturing; feedback; integrated circuit yield; intelligent control; process control; wafer-scale integration; LAN; VLSI; alignment drifts; asynchronous communications; asynchronous operations; chip quality; communications of multiple computers; computational algorithm; data filtering; data grouping; implementation challenges; real-time feedback control system; wafer fabrication line; wafer yields; Costs; Fabrication; Feedback control; Integrated circuit technology; Integrated circuit yield; Open loop systems; Process control; Real time systems; System testing; Very large scale integration;
Conference_Titel :
Electronic Manufacturing Technology Symposium, 1993, Fifteenth IEEE/CHMT International
Conference_Location :
Santa Clara, CA
Print_ISBN :
0-7803-1424-7
DOI :
10.1109/IEMT.1993.398168
