Дослідження напівпровідникового твердого розчину V1-xTixFeSb. I. Особливості електрокінетичних характеристик

The peculiarities of the temperature and concentration characteristics of resistivity and thermopower of V1-xTixFeSb semiconductor solid solution were investigated in the temperature and concentration ranges of T = 4.2 -400 K and Ті  ≈ 9.5·1019–3.6·1021 см-3 (х = 0.005 - 0.20), respectively. The existence of previously unknown mechanism for the generation of structural defects with donor nature which determined the conduction of n-VFeSb and V1-xTixFeSb was established. The acceptor type of structural defects generated in V1-xTixFeSb by substitution of V atoms by Ti ones was confirmed.Досліджено особливості температурних та концентраційних характеристик питомого електроопору та коефіцієнта термо-ерс напівпровідникового твердого розчину V1-xTixFeSb у діапазонах температур та концентрацій: Т = 4,2 – 400 К та Ті  ≈ 9.5·1019–3,6·1021 см-3 (х = 0,005–0,20). Встановлено існування невідомого раніше механізму генерування структурних дефектів донорної природи, які визначають провідність n-VFeSb та V1-xTixFeSb. Підтверджено акцепторну природу структурних дефектів, генерованих у V1-xTixFeSb, при заміщенні V атомами Ті

Features of Structural, Energy and Kinetic Characteristics of Hf_1-xEr_xNiSn Solid Solution

The features of structural, energy state and electrokinetic characteristics were investigated for Hf&lt;sub&gt;1-x&lt;/sub&gt;Er&lt;sub&gt;x&lt;/sub&gt;NiSn solid solution in the range: T = 80 – 400 K, x = 0 - 0.10. It was confirmed partly disorder crystal structure of HfNiSn compound as a result of occupation in the 4a crystallographic site of Hf (5d&lt;sup&gt;2&lt;/sup&gt;6s&lt;sup&gt;2&lt;/sup&gt;) atoms by Ni (3d&lt;sup&gt;8&lt;/sup&gt;4s&lt;sup&gt;2&lt;/sup&gt;) ones up to ~ 1 % that generates in the crystal structural defects of donor nature. It was shown that introduction of Er atoms ordered crystal structure (“healing” of structural defects). It was established mechanisms of simultaneous generation of structural defects as acceptors by substitution of Hf (5d&lt;sup&gt;2&lt;/sup&gt;6s&lt;sup&gt;2&lt;/sup&gt;) by Er (4f&lt;sup&gt;12&lt;/sup&gt;5d&lt;sup&gt;0&lt;/sup&gt;6s&lt;sup&gt;2&lt;/sup&gt;) atoms, and the donor nature defects as a result of the appearance of vacancies in the Sn (4b) atoms sites, which determines the mechanisms of conductivity for Hf&lt;sub&gt;1-x&lt;/sub&gt;Er&lt;sub&gt;x&lt;/sub&gt;NiSn.Keywords: crystal and electronic structures, conductivity, thermopower coefficient.</p

Investigation of Crystal and Electronic Structures Features of Hf1-xTmxNiSn Semiconductor Solid Solution

The features of structural, energy state and electrokinetic characteristics were investigated for Hf1 xTmxNiSn solid solution in the range: T = 80 - 400 K, x = 0 - 0.40. It was confirmed partly disorder crystal structure of HfNiSn compound as a result of occupation in the 4a crystallographic site of Hf (5d26s2) atoms by Ni (3d84s2) ones up to ~ 1 % that generates in the crystal structural defects of donor nature. It was shown that introduction of Tm atoms ordered crystal structure (“healing” of structural defects). It was established mechanisms of simultaneous generation of structural defects as acceptors by substitution of Hf (5d26s2) by Tm (4f135d06s2) atoms, and the donor nature defects as a result of the appearance of vacancies in the Sn (4b) atoms sites, which determines the mechanisms of conductivity for Hf1-xTmxNiSn. Keywords: crystal and electronic structures, conductivity, thermopower coefficient.</p

Investigation of structural, energy state and kinetic characteristics of RNiSb semiconductor (R = Gd, Lu)

The features of structural, energy state and kinetic characteristics of the p-GdNiSb and p-LuNiSb semiconductors were investigated in the temperature range T = 4.2-400 K. As example, in p-LuNiSb, the generating of structural acceptor defects as a result of the emergence of vacancies upto 6 % in the 4c positions of Ni (3d84s2) atoms and partial, up to 1.35 %, substitution of Ni (4c) atoms by Lu (5d16s2) ones was shown. Keywords: crystal structure, electronic structure, electrical conductivity, thermopower.</p

Investigation of Band Structure of ZrNiSn_1-xGa_x Semiconductor Solid Solution

The mechanism of simultaneous generation of donor-acceptor pairs in ZrNiSn1-xGax semiconductor solid solution is established. The modeled distribution of atoms in the crystal lattice of ZrNiSn1-xGax showed that the speed of movement of Fermi level εF, obtained from the band structure calculations is in agreement with experimental extracted from lnρ(1/T) dependencies. It is shown that with substitution of Sn (5s25p2) with Ga (4s24p1) atoms in 4b crystallographic site both acceptor and donor (vacancies in 4b site) defects are generated. Keywords: crystal and electronic structures, conductivity, thermopower coefficient.</span

Features of Structural, Electrokinetic, and Energy State Characteristics of ZrNiSn_1-xGa_x Solid Solution

Features of structural, electrokinetic, and energy state characteristics of ZrNiSn1-xGax semiconductive solid solution were investigated in the temperature ranges Рў = 80 - 400 K and С… = 0 - 0.15. Disorder of crystal structure for n-ZrNiSn compound as a result of occupation of Zr (4d25s2) atoms in 4a sites by Ni (3d84s2) ones up to ~ 1 % was confirmed. It generated donor levels band D1 in the band gap. It was shown that introduction of Ga (4s24p1) atoms by means of substitution of Sn (5s25p2) ones ordered crystal structure. In this case acceptor defects were generated in 4b sites and it created extended acceptor impurity band Рђ. It was suggested that with generation of acceptor structural defects the vacancies in the Sn (4b) atomic sites simultaneously generated donor defects and formed deep donor band D2 (donor-acceptor pair took place). Keywords: crystal and electronic structures, conductivity, thermopower coefficient.</span