Eurasian Journal of Physics and Functional Materials (Nov 2021)
Influence of structural defects in silicon on formation of photosensitive heterostructures Mn<sub>4</sub>Si<sub>7</sub>-Si<Mn>-Mn<sub>4</sub>Si<sub>7</sub> and Mn<sub>4</sub>Si<sub>7</sub>-Si<Mn>-M
Abstract
The paper considers the influence of a transition amorphous layer at the interface between the higher manganese silicide (HMS) Mn 4 Si 7 and silicon doped with manganese (Si ) on the photoelectric properties of heterostructures. The role of the initial structural defects in the near-surface layers of the single-crystal silicon on the penetration of manganese atoms into Si upon doping from the gas phase is shown.It has been established that at high temperatures (T>1050 ◦ C) Mn atoms deposited on the silicon surface group together (due to surface diffusion), forming droplets of liquid manganese, which dissolve the near-surface silicon layer, forming a liquid solution – a melt of Mnand Si. When Mn atoms transfer from the vapor phase into the liquid solution-melt and Si atoms diffuse into it from the boundary regions, including the amorphous bulk Si layer, the solution-melt increases in size and solidifies. During solidification, higher manganese silicide (HMS) Mn 4 Si 7 is formed, and under silicide, due to intense diffusion of Si atoms, the Si-Si bonds break, and an amorphous and elastically deformed Si region is formed, which predetermines the evolution of photoelectric phenomena in heterostructures Mn 4 Si 7 - Si-Mn 4 Si 7 and Mn 4 Si 7 -Si-M.
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