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This study focuses on developing an understanding of the mechanisms of ion beam milling induced p‐to‐n conversion in extrinsically (As or Sb) doped p‐Hg1—xCdxTe with x ≈ 0.2. The basis of modeling is the quasichemical approach and the model of superfast Hg interstitial atoms diffusion that has permitted to explain the similar conversion occurred in Hg vacancy‐doped p‐type Hg1—xCdxTe. In an acceptor doped material a donor is generated due to the formation of a complex (of interstitial Hg atom and an As or Sb atom located in the Te site). This model provides reasonably good fits with the experimental results obtained for As and Sb doped Hg1—xCdxTe epitaxial layers where the electron concentration in the converted n‐layer corresponds to the concentration of the p‐type dopants. Different efficiency of the conductivity conversion observed for As and Sb doped samples may be explained by different enthalpy of complex formation calculated for AsTe–HgI and SbTe–HgI pairs.

The paper presents the preliminary results of experiments performed to study the influence of low‐energy Ar ions on the electrical properties of p‐ and n‐type PbTe epitaxial films under ion beam milling. We demonstrate that this treatment causes p‐to‐n conversion in p‐PbTe and increases the electron concentration in n‐PbTe, with the electron mobility decreasing. The character of changes in the electrical properties allows to conclude that ion beam milling creates additional donor centres due to the preferential sputtering of tellurium.

The paper presents preliminary results of the experiments performed to study the influence of low energy Ar ions on the electrical properties of p-InSb under ion beam milling. We demonstrate that this treatment causes the 2-layer structure with electron conductivity to emerge at the p-InSb surface. The first layer with low mobility electrons is created through the surface amorphisation by ion bombardment. The second layer with higher mobility electrons is a result of crystal lattice damages. The properties of the second layer are time-dependent that indicates the gradual relaxation of damages.

Hall effect, resistivity and p-n-junction characteristics were investigated on high pure and perfect p-type Hg 1-x Cd x Te crystals (x ~ 0.2) versus temperature, doping, and a way of heat treatment. It was shown, that activation energy of extrinsic acceptors does not depend on conditions of the crystal heat treatment, while the first native acceptor level increases monotonically from 10 meV in the Hg-saturated crystal up to 15.4 meV in the Te-saturated one. The experimentally observed energy of the first level of the native acceptor in Te-saturated crystals (15.4 meV) is in a good agreement with the value 16 meV, obtained by calculation carried out in the framework of the effective mass approximation. The difference between the crystals, saturated by Hg or Te, has an essential effect for reverse dark current through a p-n-junction at T = 77 K. It should be taken into account when manufacturing the photodiodes.