Scanning tunneling microscopy/spectroscopy study of In/In4Se3 (100) nanosystem⋆

The present paper provides the results of structural studies concerning formation of self-assembled indium deposited nanostructures on the (100) surface of In4Se3 layered semiconductor. We used to study growth orientation of indium-induced nanostructures exploiting small rates and low times of indium deposition by scanning tunneling spectroscopy (STM). We carry out our studies using In4Se3 crystals grown with rather different concentrations of the over-stoichiometric indium in the melt. It has been established that shape of subsequent indium-deposited nanostructures varies from 3D islands, in the case of low-indium-doped crystals, to elongated nanowires, for highly doped ones. Based on a high-resolution STM study, we show that self-assembled quasi-periodical nanowires are oriented along the c -axis of (100) In4Se3 surface. The observed nanostructures have metallic origin as it was acquired by the current imaging tunneling spectroscopy (CITS) studies. We considered that formation of different-shaped indium-deposited nanostructures is powered by concentration of indium nuclei on furrowed (100) In4Se3 surface, which is modulated by the degree of the over-stoichiometric indium during crystal growth subsequently intercalated into the interlayer gap.