The present invention relates to a Smart Defect Calibration, Diagnosis, Sampling 
System and The Method Thereof for manufacturing fab is provided. The intelligent defect diagnosis method comprises: receiving pluralities of defect data, design 
layout data, analyzing the defect data, design layouts, by a Critical Area Analysis (CAA) 
system, wherein the analyzing step further contains the sub-steps: superposing the defect contour pattern and the design 
layout, performing CAA to identify a killer or non-killer defect based on the open or short 
failure probability, defects are classified as high, medium, low, or negligible risk defect based on the Killer Defect Index, defect 
signal parameters, selecting defect samples based on the defect classification data, selecting alarm defect and filtering false defect with pattern match with defect pattern 
library and frequent failure defect 
library, performing coordinate conversion and pattern match between 
image contour and design 
layout for coordinate correction, creating a CAA accuracy 
correction system and 
defect size calibration 
system by analyzing original 
defect size data and defect contour size from 
image analysis, evaluating the 
defect size using 
measurement uncertainty analysis with 
statistical analysis methods to reach the purposes of increasing CAA accuracy and Killer Defect 
identification rate.