A method for characterizing
semiconductor device performance variations includes
processing a
wafer in a
processing line to form a feature on the
wafer; measuring a physical
critical dimension of the feature in a first
metrology tool to generate a first
critical dimension measurement; measuring the physical
critical dimension of the feature in a second
metrology tool to generate a second critical
dimension measurement independent of the first critical
dimension measurement; determining an effective critical dimension of the feature in a third
metrology tool to generate a third critical
dimension measurement; and comparing the first, second, and third critical dimension measurements to identify a metrology drift in one of the first and second metrology tools. A
system for characterizing
semiconductor device performance variations includes a
processing line, first, second, and third metrology tools, and a process controller. The processing line is adapted to process a
wafer to form a feature on the wafer. The first metrology tool is adapted to measure a physical critical dimension of the feature to generate a first critical dimension measurement. The second metrology tool is adapted to measure the physical critical dimension of the feature to generate a second critical dimension measurement independent of the first critical dimension measurement. The third metrology tool adapted to determine an effective critical dimension of the feature to generate a third critical dimension measurement. The process controller is adapted to compare the first, second, and third critical dimension measurements to identify a metrology drift in one of the first and second metrology tools.