Patent ID: 9673022
Date: 2017-06-06
CPC Classifications: H01J,H01L

Claim:
1. A system for reviewing a wafer, the system comprising: a memory unit configured to store information about locations of a set of suspected defects that are located at multiple dice of the wafer; electron optics configured to obtain images of reference elements located within a first reference die of the wafer; a processor configured to: compare a first sub-set of suspected defects to a first sub-set of reference elements to provide a first evaluation result; and select, in response to the first evaluation result, a source of a second sub-set of reference elements; wherein the electron optics are further configured to obtain images of a second sub-set of reference elements that are located within a second reference die of the wafer when it is determined that the second reference die is the source of the second sub-set of reference elements; and wherein the processor is further configured to compare a second sub-set of suspected defects to the second sub-set of reference elements to provide a second evaluation result.