Three-Dimensional Reconstruction of the Surfaces of Relief Structures from Stereoscopic Images Obtained in a Scanning Electron Microscope

Abstract

The profi le of the surfaces of two samples of monocrystalline silicon containing trapezoidal-shaped protrusions is established by means of three-dimensional reconstruction from stereoscopic images obtained in a scanning electron microscope and the average value of the height of the protrusions is determined. The results are compared with the results of measurements by an atomic-force microscope. The advantage in terms of precision of reconstruction for a sample that has been subjected to additional plasma treatment is explained by the formation of nanodimensional morphological features of the surface in the form of contrasting elements that increase the precision of coincidence of the images in the course of 3D reconstruction.The scanning electron microscope (SEM) is one of the most frequently used devices employed in obtaining images of surfaces that possess great focal depth and high resolution (down to 1 nm). Through the use of the method of 3D reconstruction of the surface of a sample from images obtained in a scanning electron microscope, it is possible to extract information about the three-dimensional surface structure of the sample from a pair of two-dimensional SEM images obtained at different angles of inclination of the sample [1, 2]. The method utilizes the phenomenon of the stereoscopic effect, which manifests itself as a consequence of parallax, or the variation of the visible position of an object relative to a distant background as a function of the position of the observer. It is on this that, in particular, the binocular vision of man and animals is based; that is, the spatial representation of the object is formed on the basis of two images (one from the right eye and the other from the left eye) obtained from different points of view (at different angles). The spatial (volumetric) perception of the observed object (stereoscopic effect) is formed on the basis of differences in the images. Such images are called stereoscopic images (in the case of two images, a stereo pair), while the differences in the stereoscopic images are the greater, the greater are the differences in the angles at which the object is observed (stereoscopic angle).

Multidirectional Image Sensing for Microscopy Based on a Rotatable Robot

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Surface defect detection of magnetic microwires by miniature rotatable robot inside SEM

“…For instance, various title stages have been adopted to rotate samples recently. 15,16 Yet, these stages can only tilt samples within a small angle, which means that some surface defects are still invisible. To increase the title range, some manipulators and holders have been designed to rotate samples in a 360 • way.…”