Patent ID: 8000905

Claim:
A computer-implemented method for determining sizes of defects detected on a wafer, comprising: separating the defects into groups based on output acquired for the defects by multiple channels of an inspection system used to detect the defects on the wafer, wherein a first lens and a first detector form a first of the multiple channels, wherein a second lens and a second detector form a second of the multiple channels, and wherein the first and second lenses collect light scattered from the wafer at different angles; separating the defects in one or more of the groups into subgroups based on the output acquired for the defects by one or more of the multiple channels; and determining the sizes of one or more of the defects in one or more of the subgroups separately based on the output acquired for the defects by only one of the multiple channels and a calibration parameter, wherein the calibration parameter is different for each of the subgroups, wherein the calibration parameter is acquired by using another system to measure actual sizes of defects detected on other wafers, and wherein said separating the defects into the groups, said separating the defects into the subgroups, and said determining are performed using a computer system.