Механизм генерирования донорно-акцепторных пар при сильном легировании n-ZrNiSn акцепторной примесью Ga

AbstractThe nature of the mechanism of the simultaneous generation of donor–acceptor pairs under heavy doping of n -ZrNiSn intermetallic semiconductor with the Ga acceptor impurity is established. Such spatial arrangement in the crystal lattice of ZrNiSn_1– x Ga_ x is found when the rate of movement of the Fermi level εF found from calculations of the density distribution of electron states coincides with that experimentally established from dependences lnρ(1/ T ). It is shown that when the Ga impurity atom (4 s ^24 p ^1) occupies the 4 b sites of Sn atoms (5 s ^25 p ^2), structural defects of both acceptor nature and donor nature in the form of vacancies in the 4 b site are simultaneously generated. The results are discussed in the scope of the Shklovskii–Efros model of a heavily doped and compensated semiconductor.

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Synthesis, Structural, Electrical Transport and Energetic Characteristics of ZrNi1-хVxSn Solid Solution

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.3.275-281 ◽

2019 ◽

Vol 20 (3) ◽

pp. 275-281

Author(s):

L. Romaka ◽

Yu. Stadnyk ◽

V.A. Romaka ◽

A. Нoryn ◽

I. Romaniv ◽

...

Keyword(s):

Solid Solution ◽

Fermi Level ◽

Electrical Transport ◽

Energy State ◽

Structure Type ◽

Structural Defects ◽

Simultaneous Generation ◽

Heusler Phase ◽

Arc Melting ◽

Donor And Acceptor

The samples of ZrNi1-хVxSn solid solution (x = 0 – 0.10) based on the ZrNiSn half-Heusler phase (MgAgAs structure type) were synthesized by direct arc-melting with homogenous annealing at 1073 K. The electrokinetic and energy state characteristics of the ZrNi1-хVxSn semiconducting solid solution were investigated in the temperature range T = 80 - 400 K. An analysis of behavior of the electrokinetic and energetic characteristics, in particular, the motion rate of the Fermi level, ΔεF/Δx for ZrNi1-хVxSn, allows to assume about the simultaneous generation of the structural defects of donor and acceptor nature in the crystal. The additional researches are required to establish the mechanisms of donor generation.

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Features of Structural, Electrokinetic, and Energy State Characteristics of ZrNiSn1-xGax Solid Solution

Фізика і хімія твердого тіла ◽

10.15330/pcss.18.1.41-48 ◽

2017 ◽

Vol 18 (1) ◽

pp. 41-48

Author(s):

L.P. Romaka ◽

A.M. Нoryn ◽

Yu.V. Stadnyk ◽

V.Ya. Krayovskyy ◽

V.A. Romaka ◽

...

Keyword(s):

Crystal Structure ◽

Solid Solution ◽

Energy State ◽

Impurity Band ◽

Structural Defects ◽

Acceptor Impurity ◽

Acceptor Pair ◽

Deep Donor ◽

Temperature Ranges ◽

Donor Acceptor

Features of structural, electrokinetic, and energy state characteristics of ZrNiSn1-xGax semiconductive solid solution were investigated in the temperature ranges Т = 80 - 400 K and х = 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 ɛD1 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 ɛА. 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 ɛD2 (donor-acceptor pair took place).

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Investigation of Electronic Structure of Zr1-xVxNiSn Semiconductive Solid Solution

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.2.127-132 ◽

2019 ◽

Vol 20 (2) ◽

pp. 127-132

Author(s):

Yu.V. Stadnyk ◽

V.V. Romaka ◽

V.A. Romaka ◽

A.M. Нoryn ◽

L.P. Romaka ◽

...

Keyword(s):

Solid Solution ◽

Electronic Structure ◽

Electrical Properties ◽

Band Gap ◽

Electronic States ◽

Structural Defects ◽

Simultaneous Generation ◽

Density Of Electronic States ◽

Donor And Acceptor ◽

Donor Acceptor

The peculiarities of electronic and crystal structures of Zr1-xVxNiSn (x = 0 - 0.10) semiconductive solid solution were investigated. To predict Fermi level εF behavior, band gap εg and electrokinetic characteristics of Zr1-xVxNiSn, the distribution of density of electronic states (DOS) was calculated. The mechanism of simultaneous generation of structural defects of donor and acceptor nature was determined based on the results of calculations of electronic structure and measurement of electrical properties of Zr1-xVxNiSn semiconductive solid solution. It was established that in the band gap of Zr1-xVxNiSn the energy states of the impurity donor εD2 and acceptor εA1 levels (donor-acceptor pairs) appear, which determine the mechanisms of conduction of semiconductor.

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Investigation of Band Structure of ZrNiSn1-xGax Semiconductor Solid Solution

Фізика і хімія твердого тіла ◽

10.15330/pcss.18.2.187-193 ◽

2017 ◽

Vol 18 (2) ◽

pp. 187-193

Author(s):

L.P. Romaka ◽

Yu.V. Stadnyk ◽

V.V. Romaka ◽

V.Ya. Krayovsky ◽

P.-F. Rogl ◽

...

Keyword(s):

Solid Solution ◽

Band Structure ◽

Fermi Level ◽

Crystal Lattice ◽

Crystallographic Site ◽

Simultaneous Generation ◽

Band Structure Calculations ◽

Semiconductor Solid Solution ◽

Donor Acceptor ◽

Structure Calculations

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.

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Investigation of structural, electrokinetic and energy state properties of the semiconductive Zr1-xVxNiSn solid solution

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.1.39 ◽

2019 ◽

Vol 20 (1) ◽

pp. 33-39

Author(s):

V. Romaka ◽

L. Romaka ◽

Y. Stadnyk ◽

A. Horyn ◽

V. Krayovskyy ◽

...

Keyword(s):

Solid Solution ◽

Structural Change ◽

Energy State ◽

Energy Levels ◽

Lattice Parameter ◽

Structural Defects ◽

Simultaneous Generation ◽

Unknown Mechanism ◽

Donor And Acceptor ◽

Donor Acceptor

Structural, electrokinetic and energy state characteristics of the Zr1-xVxNiSn semiconductive solid solution (х=0–0.10) were investigated in the temperature interval 80–400 К. It was shown that doping of the ZrNiSn compound by V atoms (rV=0.134 nm) due to substitution of Zr (rZr=0.160 nm) results in increase of lattice parameter а(х) of Zr1-xVxNiSn indicating unforecast structural change. Based on analysis of the motion rate of the Fermi level ΔεF/Δх for Zr1-xVxNiSn in direction of the conduction band it was concluded about simultaneous generation of the structural defects of the donor and acceptor nature (donor-acceptor pairs) by unknown mechanism and creation of the corresponding energy levels in the band gap of the semiconductor.

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