The Three-Layer Structure of Pb0.8Sn0.2Te Epitaxial Films Prepared by MBE Technique on BaF2

The Hall effect is investigated in pPb0.8Sn0.2Te films within the T= 70 to 600 K range in a vacuum cryostal with samples having no contact with the atmosphere after annealing. It is found that at the heating temperatures T ≈︁ 520 K and above the temperature‐dependent behaviour of the Hall coefficient, RH, begins to change which leads to the shift of the RH inversion temperature to the low range down converting the conductance into n‐type over the entire temperarature range. The results obtained are explainable by a three‐layer p‐n‐p model, where p is the quasi‐volume, n a subsurface layer associated with the sample production technique, p+ a thin surface layer caused by contact with the atmosphere. The Auger analysis data point to the role of tellurium in the formation of the layer film structure. [Russian Text Ignored].