INVESTIGATIONS OF THE SURFACE MORPHOLOGY OF Mn4Si7

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Abstract

In this work, we studied the surface morphology of a film of higher manganese silicide before and after heating. The mechanism of formation of a film of higher manganese silicide has been studied. The resulting silicon film was formed on the surface of SiO₂/Si or mica by magnetron sputtering. The morphology, composition, electrical and optical properties of bulk samples and Mn4Si7 vacuum coatings obtained by magnetron sputtering on the SiO2/Si structure have been studied. It is shown that manganese silicide coatings with a thickness of about 150 nm are similar in properties to bulk Mn4Si7 and have a homogeneous fine-grained semiconductor structure characterized by thermal sensitivity up to 20-30 Mv per degree. In addition, the article presents the electrophysical properties of films of high manganese silicide obtained by the authors by magnetron sputtering. Heated Mn4Si7-146 nm coated films have a homogeneous structure with fine grains, which is due to the sufficient coating density. Since Mn4Si7 nanoclusters are semiconductor materials, it can be assumed that energy barriers for charge carriers will exist at the interface of a nanocluster with an amorphous phase separating this phase. The increase in thermal sensitivity from 0 mv/K to 20 MV/K up to 800 K is explained by the disappearance of energy barriers for charge carriers at the nanocluster-amorphous phase interface due to the ordering of nanoclusters. The change from 20 mv/K to 28 MV/K during cooling is explained by the appearance of structural relaxation in the amorphous phase.