An MILP approach to wafer sampling and selection

RP Good, MA Purdy - IEEE Transactions on Semiconductor …, 2007 - ieeexplore.ieee.org
RP Good, MA Purdy
IEEE Transactions on Semiconductor Manufacturing, 2007ieeexplore.ieee.org
This paper introduces a novel algorithm for selecting the optimal wafers for measurement
given a set of selection rules. The algorithm is based on assigning a penalty to each of the
sampling rules and then using a mixed-integer linear program to pick the wafers which
minimize the sum of the penalties. By waiting until the metrology step to determine the best
wafers to measure, a real-time decision can be made based on which wafers have
previously been measured, the tools and chambers on which wafers were processed, and …
This paper introduces a novel algorithm for selecting the optimal wafers for measurement given a set of selection rules. The algorithm is based on assigning a penalty to each of the sampling rules and then using a mixed-integer linear program to pick the wafers which minimize the sum of the penalties. By waiting until the metrology step to determine the best wafers to measure, a real-time decision can be made based on which wafers have previously been measured, the tools and chambers on which wafers were processed, and other user-specified selection criteria. The penalties can also be increased after a rule violation to ensure that each of the selection rules are satisfied at a finite frequency.
ieeexplore.ieee.org