Перегляд за Автор "Bogoboyashchiy, V."

Зараз показуємо 1 - 4 з 4

Conductivity type conversion in p- CdXHg1-XTe
(2003) Berchenko, N.; Bogoboyashchiy, V.; Izhnin, I.; Vlasov, Andriy; Kurbanov, K.; Yudenkov, V.; Берченко, Н.; Богобоящий, В.; Іжнін, І.; Власов, Андрій; Курбанов, К.; Юденков, В.
Investigations and comparative analysis of p-to-n type conductivity conversion processes on the identical samples of vacancy doped p-CdxHg–xTe (x 0.2) under ion-beam milling (IBM) and anodic oxide annealing and on the identical samples of As-doped p-CdxHg1–xTe (x 0.22) under IBM and anodic oxide annealing have been carried out. The conductivity type conversion has been observed at the considerable depth of the vacancy doped material both under IBM or under anodic oxide annealing while in the case with As-doped material only under IBM. It was considered that conversion in all these processes was determined by the mercury interstitial diffusion from corresponding mercury diffusion source and recombination with its native acceptors – cationic vacancies (in the first case) or with donor complex formations (in the second one). It has been shown that in the vacancy-doped p-CdxHg1–xTe the effective diffusion coefficients for the mercury interstitials that determines the depth of the converted layer are equal each other at equal temperatures either under thermal annealing in the saturated mercury vapour or anodic oxide annealing. It proves the identity of the mercury concentration in the diffusion source. Absence of the conversion under anodic oxide annealing in the As-doped p-CdxHg1–xTe is explained by insufficient Hg concentration in the source and it matches well with necessary condition for donor complex formation as it takes place under IBM.
Defect Structure Rebuilding by Ion Beam Milling of As and Sb Doped p-Hg1–xCdxTe
(2002) Berchenko, N.; Bogoboyashchiy, V.; Izhnin, I.; Vlasov, Andriy; Берченко, Н.; Богобоящий, В.; Іжнін, І.; Власов, Андрій
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.
High temperature arsenic doping of CdHgTe epitaxial layers
(2004) Vlasov, Andriy; Bogoboyashchiy, V.; Bonchyk, O.; Barcz, A.; Власов, Андрій; Богобоящий, В.; Бончик, О.
Experimental results on solid-state arsenic doping of the n-type bulk and ISOVPE epitaxial CdXHg1-XTe (X = 0.19÷0.3) alloys are presented. The arsenic doped thin epitaxial CdxHg1-xTe films (nAs ≈ 5⋅1016÷1⋅1020 cm-3; d =2÷5 μm) obtained by RF sputtering in a mercury glow discharge were used as As diffusion sources. The arsenic diffusion and activation were carried out at temperatures Т = 500÷600°С under Hg vapour pressure. Immediately after the high temperature treatment all samples were annealed to annihilate point defects. The SIMS analysis was used for determination of the quantitative admixture distribution of As in the diffusion area. The arsenic electrical activity has been evaluated by means of differential Hall, resistivity and thermoemf measurements. The analysis of experimental data obtained as well as their comparison with previously obtained results has been performed.
Mechanism for conversion of the conductivity type in arsenic doped p-CdxHg1–xTe subject to ionic etching
(2001) Bogoboyashchiy, V.; Vlasov, Andrii; Izhnin, I.
Based on an analysis of chemical diffusion of mercury in p-CdxHg1–xTe:As narrow-band solid solutions, a mechanism for conversion of the conductivity type upon ionic etching is suggested. It is shown that the n–p conversion of the conductivity in this case is due to the formation of a donor complex between arsenic in the Te sublattice and an interstitial Hg atom. Moreover, the electron concentration in the converted layer corresponds to the concentration of the implanted arsenic impurity. The theoretical results are confirmed by the experimental investigation of the electron concentration distribution over the n-layer of a p-CdxHg1–xTe:As epistructure converted upon ionic etching.