With the development of the VLSI(VLSI: Very Large-scale Integration), a ICs chip could hold more than ~ transistors, and the failure rate has been reduced to 10 FET level. The requirement has emerged for the new process quality and reliability evaluative technique in the microcircuit manufacture. A new multivariate control module is introduced in this paper. frequently the pattern ot points on the multivariate control chart will contain information, about whether the process h control. It is show in this paper that the interpretation of a out-of-control sign& ~m a T2 statistic is greatly aided if the corresponding value is partitioned into independent ~ rts. Information on which characteristic is significantly contributing to the out-of-control signal is readily available from this decomposition. The EWMA(The Exponentially Weighted ~æ…½ng-Average~ rnnt æƒced in detecting small shifts. Several dilemma ci . Japability lnde~~ ~is paper. A new definition a~.. ostimation of the process capability inu~x is ~ A curve-fitting approach to the estimation problem is taken. The result is more precise than the general points estimation methods. It can be applied to the case of non-normal processes too. These teæ‹hnique are used to the software YP?憕hich have been applied to a GaAs de,vice manufacturing process in the NO.55 insti...
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