Structural and Some Electrophysical Properties of the Solid Solutions Si1 – xSnx (0 ≤ x ≤ 0.04)

Saidova A. S., Usmonova Sh. N., Kalanov M. U., et al. Structural and Some Electrophysical Properties of the Solid Solutions Si1 – xSnx (0 ≤ x ≤ 0.04). // Physics of the Solid State. 2013. V. 55. No. 1. pp. 36–44.

Films of the solid solutions Si1 – xSnx (0 ≤ x ≤ 0.04) on Si substrates have been grown by liquid phase epitaxy. The structural features of the films have been investigated using Xray diffraction. The temper ature behavior of current–voltage characteristics and the spectral dependence of the photocurrent for the heterostructures pSi–nSi1 – xSnx (0 ≤ x ≤ 0.04) have been analyzed. The grown epitaxial films of the solid solutions Si1 – xSnx (0 ≤ x ≤ 0.04) have a perfect singlecrystal structure with a (111) orientation and a subgrain size of 60 nm. In the epitaxial films at the Si–SiO2 interfaces between silicon subgrains and SiO2 nanocrystals, where there are many sites with a high potential, the Sn ions with a high probability substitute for the Si ions and encourage the formation of Sn nanocrystals with different orientations and, as follows from the analysis of the Xray diffraction patterns, with different sizes: 8 nm (for the (101) orientation) and 12 nm (for the (200) orientation). The current–voltage characteristics of the heterostructures pSi–nSi1 – xSnx (0 ≤ x ≤ 0.04) are described by the exponential law J = J0exp(qV/ckT) at low voltages (V < 0.2 V) and the square law J = (9qμpτpμnNd/8d3 )V2 at high voltages (V > 1 V). These results have been explained by the drift mechanism of charge carrier transport in the electrical resistance relaxation mode.

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