COMPARISON OF THE EFFICIENCY OF DIFFERENT DETECTORS OF THE SCANNING ELECTRONIC MICROSCOPE «MIRA-LMH» FOR STUDYING MICROSTRUCTURE OF NANOMATERIALS

Abstract

At the first stage, the objects of study were synthesized – silicon dioxide by the Stober method, where tetraethoxysilane was used as a precursor, and a nanocomposite ZnO-Au by the sol-gel method using the aqueous zinc acetate dihydrate as a precursor. At the second stage, the microstructure and morphology of the obtained samples were investigated by scanning electron microscopy on a «MIRA-LMH» scanning electron microscope (Tescan company) using both a classical secondary electron detector and additional detectors – intralens secondary electron detector and back-scattered electrons detector. As a result of the research, it was found that when using the secondary electron detector, practically no noise images with topographic contrast are obtained. When using the intralens secondary electron detector, images of only material contrast are created, without the influence of the surface relief. Also, the use of this detector made it possible to obtain high-quality images with a high resolution at a distance of 5 mm from the sample. When using a back-scattered electrons detector with a working distance to the sample of 8 mm and increasing the resolution of the microscope, the resulting images have low border contrast, but represent compositional information with high sensitivity. Thus, it was found that the intralens secondary electron detector with a working distance of 5 mm to the sample is optimal for obtaining clear images of the microstructure of the surface of nanomaterials at multiple magnifications.

Keywords

• silicon dioxide
• nanocomposite zno-au
• scanning electron microscopy
• detectors
• microstructure