Patent ID: 7449699

Claim:
A method of creating a topography at a surface of a specimen, the method comprising: providing desired surface height values for one or more locations at the surface of the specimen; providing, an energetic particle column comprising a source of energetic particles, the energetic particle column operatively arranged to form the energetic particles into a beam, a controller connected to the energetic particle column, the controller and the energetic particle column operatively arranged to direct the beam of energetic particles to the one or more locations and to provide doses of energetic particles to the one or more locations and, an interferometer integrated with the energetic particle column, the interferometer comprising a light source and a reference mirror, the interferometer connected to the controller, the interferometer operatively arranged with respect to the energetic particle column to illuminate an area at the surface of the specimen comprising at least a part of the one or more locations with a first portion of light from the light source and, to illuminate the reference mirror with a second portion of light from the light source; exposing to first doses of energetic particles, the one or more locations; measuring current surface height values at the one or more locations by interferometrically combining a reflected first portion of light from the illuminated area, with a reflected second portion of light from the reference mirror; comparing the desired surface height values to the current surface height values to determine a difference and, calculating second doses of energetic particles for the one or more locations, based upon the difference; and, exposing to second doses of energetic particles, the one or more locations.