Simple separations of topographic and material contrasts using one annular type in-lens detector of low-voltage SEM

Contrasts of low-voltage secondary electron microscope images have been experimentally investigated using commercial instruments having an annular type in-lens (IL) detector. The topographic and material contrasts of oxide particles on steel surfaces in the secondary electron microscope images recorded by the IL and the Everhart-Thonley detectors systematically change as a function of working distance. It is found that these two contrasts are divided using the different concentric areas of the IL detector surface. These results are discussed in terms of the kinetic energy of the detected electrons. Two simple methods for the information selection using one IL-type detector are proposed. Copyright (c) 2015 John Wiley & Sons, Ltd.