Patent ID: 8207499

Claim:
A method for imaging a surface of an object, comprising: scanning at least one region of the surface with a charged particle beam, wherein during a portion of the scanning, the charged particle beam is scanned in one direction along a one-dimensional beam path; during the scanning in the one direction along the one-dimensional beam path, changing a scan rate of the charged particle beam from a first non-zero scan rate to a second non-zero scan rate, the first scan rate being different than the second scan rate; detecting a secondary electron beam comprising secondary electrons generated from an interaction between the charged particle beam and the surface; and generating an image of the at least one region of the surface in response to the detected secondary electron beam, wherein during the scanning along the one-dimensional beam path, the scanning transitions from the first scan rate to the second scan rate at a point on the one-dimensional beam path, and a location of the point is based on a current transition in the secondary electron beam, the current transition measured prior to the scanning along the one-dimensional beam path.