Patent ID: 8594975

Claim:
A method utilizing a processor included in a computer system for characterizing an anomaly feature on a wafer, the method comprising the steps of: obtaining wafer surface measurement data yielding radial profile Z(r, θ) of sensed height information, within at least a sector in the near edge region of the wafer (edge roll off region); determining radial profile Z(r, θ) of sensed height information for the wafer along at least a radial line within the sector; obtaining a ZDD profile ZDD(r,θ)=d 2 /dr 2 Z(r,θ), the second derivative curve of radial profile Z(r, θ) of sensed height information, and a ZDDD profile ZDDD(r,θ)=d/dr ZDD(r, θ)=d 3 /dr 3 Z(r,θ); processing the ZDD profile and the ZDDD profile to produce a slope profile; determining an anomaly span metric from the slope profile; processing the ZDD profile and the ZDDD profile to produce a height profile; and determining an anomaly height metric from the height profile.