Patent ID: 7844100

Claim:
A method for inspecting a sample, comprising: receiving, by a processor, an image of the sample from an imaging system; receiving, by the processor, a definition of image attributes that are characteristic of defects; processing, by the processor, an image of the sample so as to identify candidate defects on the sample; forming, by the processor, distributions of values of the respective attributes from the candidate defects; selecting, by the processor, a set of the candidate defects that are characterized by respective candidate attribute values that fall in one or more tails of the distributions; presenting, by the processor via a monitor, the selected set to a human operator; receiving from the operator, by the processor via a computing system, respective classifications of the candidate defects in the selected set, wherein the defects may be classified as at least one of a true defect and a false alarm defect; and iteratively refining, by the processor, a definition of the one or more tails of the distributions responsively to the classifications until a criterion of a false alarm rate is met.