CPC H01L 21/681 (2013.01) | 17 Claims |
1. An overlay measurement device for measuring an error between a first overlay mark and a second overlay mark respectively formed on different layers of a wafer, the overlay measurement device comprising:
a light source;
a beam splitter that splits a beam from the light source into two beams;
a spectrum filter for adjusting a central wavelength and a bandwidth of the beam split by the beam splitter to obtain the first overlay mark image or the second overlay mark image;
a detector for obtaining the first overlay mark image or the second overlay mark image;
a transmission and receipt part; and
a processor connecting to the transmission and receipt part electrically,
wherein the processor is configured to:
obtain data transmitted from a user terminal through the transmission and receipt part,
analyze a recipe included in the data,
perform optimization of measurement options of a wafer, based on the recipe, after the recipe is analyzed,
measure the spectrum filter once with a filter wheel to calculate statistical values in relation to a plurality of parameters for each filter on the filter wheel, and
assign weights respectively to the calculated statistical values, and perform a filter optimization process selecting a filter having a minimum sum of the statistical values to which the weights is assigned respectively, as the spectrum filter.
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