Title :
A general equipment diagnostic system and its application on photolithographic sequences
Author :
Leang, Sovarong ; Spanos, Costas J.
Author_Institution :
Bain & Co., San Francisco, CA, USA
fDate :
8/1/1997 12:00:00 AM
Abstract :
This paper presents a general diagnostic system that can be applied to semiconductor equipment to assist the operator in finding the causes of decreased machine performance. Based on conventional probability theory, the diagnostic system incorporates both shallow and deep level information. From the observed evidence, and from the conditional probabilities of faults initially supplied by machine experts (and subsequently updated by the system), the unconditional fault probabilities and their bounds are calculated. We have implemented a software version of the diagnostic system, and tested it on real photolithography equipment malfunctions and performance drifts. Initial experimental results are encouraging
Keywords :
deep levels; diagnostic expert systems; fault diagnosis; integrated circuit manufacture; photolithography; probability; deep level information; equipment diagnostic system; machine performance; performance drifts; photolithographic sequences; probability theory; semiconductor equipment; shallow level information; unconditional fault probabilities; Data structures; Degradation; Engines; Humans; Lithography; Power system modeling; Probability; Software performance; Software testing; System testing;
Journal_Title :
Semiconductor Manufacturing, IEEE Transactions on
