Surface reconstruction with the photometric method in SEM

The authors present an improved method for three-dimensional reconstruction of the surface topography, which evolved from the group of photometric methods. It consists in directional acquisition of secondary electrons generated with a known angular distribution, in a four-detector system. Thanks to proper signal processing, the topography can be obtained and displayed in a form of the fully three-dimensional axonometric view. The authors propose new numerical procedures of the signal processing, which may curb the errors inherent in the method. The presented method is particularly useful for the reconstruction of relatively smooth objects, without surface details numerous enough to be identified in the “stereo pair” used in a more popular “stereoscopic method”.