Optical properties of ternary alloys MgZnO in the infrared spectrum
Properties of thin films of ternary alloys MgₓZn₁₋ₓO on the optically anisotropic Al₂O₃ substrates in the area of “residual rays” of film and substrate are first investigated using the method of infrared spectroscopy and dispersion analysis of reflection coefficients. It was established that the cha...
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| Опубліковано в: : | Semiconductor Physics Quantum Electronics & Optoelectronics |
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| Дата: | 2018 |
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
2018
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| Цитувати: | Optical properties of ternary alloys MgZnO in the infrared spectrum / E.F. Venger, I.V. Venger, N.O. Korsunska, L.Yu. Melnichuk, O.V. Melnichuk, L.Yu. Khomenkova // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 417-423. — Бібліогр.: 25 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1860479633457152000 |
|---|---|
| author | Venger, E.F. Venger, I.V. Korsunska, N.O. Melnichuk, L.Yu. Melnichuk, O.V. Khomenkova, L.Yu. |
| author_facet | Venger, E.F. Venger, I.V. Korsunska, N.O. Melnichuk, L.Yu. Melnichuk, O.V. Khomenkova, L.Yu. |
| citation_txt | Optical properties of ternary alloys MgZnO in the infrared spectrum / E.F. Venger, I.V. Venger, N.O. Korsunska, L.Yu. Melnichuk, O.V. Melnichuk, L.Yu. Khomenkova // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 417-423. — Бібліогр.: 25 назв. — англ. |
| collection | DSpace DC |
| container_title | Semiconductor Physics Quantum Electronics & Optoelectronics |
| description | Properties of thin films of ternary alloys MgₓZn₁₋ₓO on the optically anisotropic Al₂O₃ substrates in the area of “residual rays” of film and substrate are first investigated using the method of infrared spectroscopy and dispersion analysis of reflection coefficients. It was established that the changes in the thickness of the film and the content of Mg substantially deform the spectrum of reflection in the area of “residual rays” of the film and the substrate, decreasing the reflectivity. First, by means of Kramers–Kronig relations with the use of the method of dispersion analysis of infrared reflection spectra, the static dielectric constant of MgₓZn₁₋ₓO structure has been obtained at different values of х, when orientation is Е⊥С. It was ascertained that the MgₓZn₁₋ₓO/Al₂O₃ structures are well modelled when using the mutually agreed parameters, obtained earlier for the single crystals of magnesium oxide, zinc oxide, and leicosapphire at the orientation Е⊥С. It was theoretically shown and experimentally grounded that the assurance of the obtained optical parameters of MgₓZn₁₋ₓO films by the non-destructive method of infrared spectroscopy in the wide spectral range. The obtained results are well in agreement with the literature data.
|
| first_indexed | 2026-03-23T18:47:22Z |
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ISSN 1560-8034, 1605-6582 (On-line), SPQEO, 2018. V. 21, N 4. P. 417-423.
© 2018, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
417
Optics
Optical properties of ternary alloys MgZnO in infrared spectrum
E.F. Venger
1
, I.V. Venger
1
, N.O. Korsunska
1
, L.Yu. Melnichuk
2
, O.V. Melnichuk
2
, L.Yu. Khomenkova
1
1
V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, prosp. Nauky, 03680 Kyiv, Ukraine
2
Mykola Gogol State University of Nizhyn, 2, Hrafska str., 16600 Nizhyn, Ukraine
E-mail: mov310310@gmail.com
Abstract. Properties of thin films of ternary alloys MgхZn1–хO on the optically-anisotropic
Al2O3 substrates in the area of “residual rays” of film and substrate are first investigated
using the method of infrared spectroscopy and dispersion analysis of reflection coefficients.
It was established that the changes in thickness of film and content of Mg substantially
deform the spectrum of reflection in the area of “residual rays” of film and substrate,
decrease the reflectivity. First by means of Kramers–Kronig relations with use of the
method of dispersion analysis of infrared reflection spectra, the static dielectric constant of
MgхZn1–хO structure has been obtained at different values of х, when orientation is Е⊥С. It
was ascertained that the MgхZn1–хO/Al2O3 structures are well modelled when using the
mutually agreed parameters, obtained earlier for the single crystals of magnesium oxide,
zinc oxide and leicosapphire at the orientation Е⊥С. It was theoretically shown and
experimentally grounded the assurance of the obtained optical parameters of MgхZn1–хO
films by the non-destructive method of infrared spectroscopy in the wide spectral range.
The obtained results are well agreed with the literature data.
Keywords: optical properties, ternary alloys, MgZnO, infrared spectrum, infrared
spectroscopy, dispersion analysis of reflection coefficients.
doi: https://doi.org/10.15407/spqeo21.04.417
PACS 78.20.Ci, 78.40.-q
Manuscript received 23.10.18; revised version received 15.11.18; accepted for publication
29.11.18; published online 03.12.18.
1. Introduction
Today zinc oxide (ZnO), due to its high radiation,
chemical and thermal stability, is an enough applicable
semiconductor in acousto-, opto- and nanoelectronics [1-
4]. Zinc oxide is especially actual when making the
transparent film electrodes for solar cells [5], and high
binding energy of excitons (60 meV) in ZnO promotes
laser generation at room temperature [1, 2]. A bandgap
(Eg = 3.37 eV) allows to use ZnO for creation of
detectors and filters in the ultraviolet range. In addition,
zinc oxide found wide application for manufacturing gas
sensors, light-emitting diodes, varistors, photocatalizators
for cleaning water and air etc. [5]. In its turn, ZnO films
on Si and CdTe substrates have considerably subzero
prime price and are perspective material for creation of
antireflective, current-carrying layers in solar cells of
large area [5-7].
Next to ZnO, there is another widely used material
that has excellent characteristics in application, it is
magnesium oxide (MgO). MgO is one of the most
widespread natural minerals that is crystallized in the
rocky structure of Earth at any pressures and
temperatures [8]. The crystals of MgO are transparent,
fire and explosion undangerous, practically insoluble in
water, however soluble in muriatic, sulphuric and vinegar
acids. MgO has a high temperature of melting 2800 °С,
that is why it is widely used as substrate material for the
processes of growing thin films in modern
microelectronic and optronic devices [8, 9].
In the works by Ye.F. Venger and coauthors
[10-12], the analysis of both ZnO and MgO compounds
was performed, which is a result of that ZnO is
compound of semiconductor of family А2
В
6, and MgO is
usually examined as a widegap semiconductor close to
dielectric, as its bandgap is 8.2 eV. MgO has a cubic
structure like NaCl type. However, in spite of the fact
that ZnO and MgO have different crystalline structures,
zinc oxide has a hexagonal crystalline structure
(wurtzite), and magnesium oxide – the cubic one, these
two materials can be connected with each other, forming
the MgхZn1-хO compound. The obtained ternary
compound extends the limits of their application. First it
was described in the works Kawasaki et al. [13], where
the possibility to change optical and electrophysical
properties of ternary alloys MgхZn1–хO by changing the
bandgap in ZnO films was shown.
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
418
Thus, for the increase of Eg it needs to use the
elements of the second group that are placed higher in the
Mendeleyev table, for example Mg [13], and for decrease
– elements that are below, for example Cd [14]. In the
dependence on the relative concentrations of Mg and Zn,
ternary alloys MgхZn1–хO may have both hexagonal
crystalline structure (wurtzite) and the cubic one. In the
work [15], it was shown that at х < 0.3 hexagonal
crystalline structure is inherent to MgхZn1–хO and
bandgap changes from 3.4 up to 3.8 еV, which allows to
use them for manufacturing substances for
optoelectronics with the range of wavelengths from red
up to deep ultravoilet. At х > 0.3, cubic crystalline
structure is inherent to MgхZn1–хO. Thus, due to the
unique properties (high photo-response, high quantum
yield of photo- and cathodoluminescence, presence of
pyro- and piezoelectric effects etc.), MgхZn1–хO films
belong to materials that provide a base for the various
optoelectronic devices that were created with the use of
volume and surface waves. Advantage of the devices
based on MgхZn1–хO is their diminutiveness, high
efficiency of operation in a wide frequency range, use in
optics and optoelectronics, in light-emitting diodes for
the ultraviolet spectral region, in laser diodes or sensors,
as well as possibility of integration with other
microelectronic elements [15-20].
However, data about study of undoped and strong
doped films of MgZnO at the concentrations of electrons
from 1016 to 5·1018 сm–3 on the Al2O3 dielectric substrates
by using the method of infrared spectroscopy of external
reflection in the area of “residual rays” of film and
substrate at the orientations E⊥C and E||C in the literature
is lighted up limit enough.
Attractiveness to research the ternary alloys
MgхZn1–хO with the range of Mg2+ from 0 to 30% is
keeping the hexagonal lattice and displaying the
optically-anisotropic properties in the infrared spectrum.
At х > 30%, the cubic lattice of the considered ternary
alloys is typical.
The aim of this work was to study optical properties
of films of ternary alloys MgхZn1–хO on the optically-
anisotropic Al2O3 substrates by means of the method of
spectroscopy of external infrared reflection.
2. Samples and the method for measuring
Synthesis of the films was performed using the industrial
modernized setup ВУ-1А and possibilities of computer
controlling the technological parameters (temperature,
pressure, position of shutters etc.). It was shown that the
developed software allowed the operator to force setup
into an operation mode, to synthesize automatically thin
films (at the set temperature conditions, thickness,
concentrations of free charge carriers etc.) and remove of
setup from operation mode. The rate of MgхZn1–хO film
growth at х < 20% on the Al2O3 substrates was
0.1…0.15 µm/hour. The thickness of films was
determined by means of the interferometer МИИ-4 and
changed from 0.1 up to 10 µm.
As a substrate for growing monocrystalline zinc
oxide layers, single crystals of leicosapphire were used.
In the hexagonal Al2O3 single crystals there is a plane
that is perpendicular to z-axis that is designated (0001),
and in rhombohedral ones – (111) [21]. From the
possible variety of sapphire orientations for epitaxial
growing the ZnO thin films, advantage was given to
orientations with the densely packed planes (0001),
(1102), (1120), (1012), on which it is possible to grow
the layers with high mobility of charge carriers [21, 22].
By means of the spectrophotometer ИКС-29М and
the use of facility ИПО-22 at Т = 300 K, the spectra of
external reflection of Al2O3 substrate were measured
within the range 400…1200 сm–1. A mathematical model
with the additive and phenomenological contribution of
oscillators to permittivity was presented. The spectra of
infrared reflection for MgхZn1–хO/Al2O3, which allows to
perform the dispersion analysis of spectra with account
of orientation inherent to optical axes in film and
substrate.
3. Theory and discussion of results
Let us consider the structure of MgхZn1–хO/Al2O3 that
consists of absorptive film on the absorptive semi-infinite
substrate. The area of “residual rays” of ternary alloy
MgZnO comprises the range from 400 up to 1000 сm–1.
In the monographs [10, 25], there was shown the
possibility to model semiconductor or dielectric structure
that consists of optically-anisotropic (isotropic) film on
the optically-anisotropic (isotropic) substrate, when using
the multioscillometric mathematical model for the
orientations E⊥C and E||C. In addition, calculation of
spectra of infrared reflection from the MgхZn1–хO/Al2O3
surface was carried out after formulas that take into
account interaction of infrared emission with the phonon
and plasma subsystems of film and semi-infinite
substrate of Al2O3 for the case E⊥C and E||C:
( )
( ) ( ) ( ) ( )
( ) ( ) ( ) ( ) 222
2
2
2
2
2
1
2
12
222
2
2
2
22
2
1
2
1
sincosexpexp
sincosexpexp
δ+δ+γ−++++γ
δ+δ+γ−++γ+
=
=ν
DChqhq
BAhqhq
RT
,
where
( )21212 hhqqA += , ( )12212 hqhqB += ,
( )21212 hhqqC += , ( )12212 hqhqD += ,
( ) 2
2
2
21
2
2
2
2
2
1
1
knn
knn
q
++
−−
= ,
( ) ( )2
32
2
32
2
3
2
2
2
3
2
2
2
kknn
kknn
q
+++
−+−
= ,
( ) 2
2
2
21
21
1
2
knn
kn
h
++
= ,
( )
( ) ( )2
32
2
32
2332
2
2
kknn
knkn
h
+++
−
= ,
λ
π
=γ
dk2
2
4
,
λ
π
=δ
dn2
2
4
(n1, n2, n3 are the indexes of refraction; k1, k2, k3 –
indexes of absorption inherent to air, film with the
thickness d and semi-infinite substrate, respectively).
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
419
Table 1. Parameters of Al2O3 single crystal for calculation of
R(ν) at the orientation Е⊥C.
νTOi, cm–1 384 442 571 634
∆εi 0.2 2.8 3.1 0.2
γfi /νTOi 0.015 0.01 0.2 0.02
Table 2. The mutually agreed volume parameters of single
crystals of magnesium oxide [12, 26] and zinc oxide [10] (Т =
293 K).
ZnO ε0 ε∞ νTO, cm–1 νLO, cm–1
ZnO (E⊥C) 8.1 3.95 412 591
ZnO (E||C) 9.0 4.05 380 570
MgO (E⊥C) 2.98 9.39 416 738
Fig. 1. Calculated spectra of infrared reflection R(ν) of single
crystals MgO (1), ZnO (2), Al2O3 (3) at the orientation E⊥C.
Calculation of n2 and n3 was performed as based on
the model of permittivity with additive contribution of
active optical phonons νТO and plasmons νр [10, 25]:
( ) ( ) ( )
( )
( )pi
pii
fiTOi
TOiLOii
i
ii
jj
j
γ+νν
νε
−
νγ−ν−ν
ν−νε
+ε=
=νε+νε=νε
∞∞
∞
2
22
22
21MgZnO
where νLO, νТO are the frequencies of longitudinal and
transversal optical phonons; γf is the fading coefficient of
optical phonon; γр and νр are fading coefficient and
frequency of plasmon resonance; and і = 1…3 are
indexes of oscillators in the film. When modeling the
Al2O3 substrate, we used the dependence of permittivity
of sapphire on frequency for Е⊥С [10]:
( ) ∑
=
∞
νγ+ν−ν
νε∆
+ε=νε
4
1
22
2
i fiTOi
TOii
j
, (2)
Fig. 2. Spectra of infrared reflection R(ν) of zinc oxide film on
substrate of Al2O3 single crystal of the orientation E⊥C: 1 –
experiment (d = 0.1 µm); 2 – calculation of R(ν) at γf⊥ =
12 сm-1, νp⊥ = 480 сm–1, γp⊥ = 800 сm–1; 3 – calculation of R(ν)
for ZnO film (without substrate).
where ε∞ is a high-frequency permittivity of sapphire for
the orientation Е⊥С (it was accepted to be equal to 3.2);
∆εi is the force of i-th oscillator; νТOi – frequency of
transversal optical fading of i-th oscillator; γfi is the value
of fading coefficient of i-th oscillator. The data used for
the calculation of spectra R(ν) from the Al2O3 surface
were listed in Table 1.
In Fig. 1, the spectra of infrared reflection of single
crystals of magnesium oxide (curve 1), zinc oxide
(curve 2) and aluminium oxide (curve 3) at the
orientation of E⊥C are presented, which were measured
with account of the data [10, 12]. For modeling the
spectra of infrared reflection, the mathematical
expressions of multioscillometric mathematical model
(1) and (2) were used. The mutually agreed parameters of
oscillators for the indicated single crystals are presented
accordingly in Tables 1 and 2.
The area of “residual rays” of MgO, ZnO single
crystals is located within the range 400 to 1000 сm–1,
which complicates task of exact determination of
influence of optical parameters on characteristics of the
reflection spectrum for every separately taken material.
In addition, zinc oxide is a semiconductor where optical
and electrophysical properties influence on the spectrum
of reflection depending on the degree of doping the
single crystal and type of charge carriers. It should be
noted that each single crystal of presented in Fig. 1 ones
was thoroughly studied by the authors earlier [10, 12].
To study the influence of properties inherent to
optically-isotropic film on the spectrum of infrared
reflection, the double-layer ZnO/Al2O3 and MgO/Al2O3
structures were used.
In Fig. 2, we show the experimental (points 1) and
theoretical (curve 2) results of research of
monocrystalline films of zinc oxide with the thickness
0.1 µm at Е⊥С by the methods of spectroscopy of
infrared reflection. Experimental spectra were measured
using the spectrometer ИКС-29М with the facility ИПО-
22 (taking into account the method described in [10])
0 400 600 800 1000 ν, cm–1
0.4
0.6
1.0
1 2 3 2 1 3
2
1
300 700 1100
0.5
1
ν, cm–1
R(ν)
1
1 2 3
0
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
420
Fig. 3. Spectra R(ν) of the ZnO/Al2O3 structure: 1 – experiment
(d = 0.5 µm); 2 – calculation of R(ν) at νTO⊥ = 412 сm–1, γf⊥ =
15 сm–1, νp⊥ = 400 сm–1, γp⊥ = 870 сm–1; 3 – calculation of R(ν)
for ZnO film (without substrate).
within the range 400 to 1400 сm–1. The spectra were
registered in the polarized irradiation at the orientation of
electric vector of E⊥C of Al2O3 crystal. The curve 1
(points) corresponds to the experimental values of R(ν) of
ZnO/Al2O3 structure with the thickness of ZnO layer d =
0.1 µm. The calculated spectrum from the ZnO/Al2O3
surface was measured at parameters for ZnO film, which
were presented in signatures to Fig. 2 and data of Tables
1 and 2. As it is evident from the figure, in the spectrum
there are minima at the frequencies 475, 505, 620 сm–1.
In the absence of ZnO film, minima in the Al2O3 spectra
are at the frequencies 390, 420, 489, 633 сm–1 (Fig. 1,
curve 3).
It is shown in theory that when the thickness is less
than 80 nm, the shape of the spectrum R(ν) is defined
mainly by Al2O3 substrate, and the zinc oxide layer of the
thickness 10 µm forms the spectrum of reflection of
semi-infinite zinc oxide single crystal. The change in
sample orientation in the polarized radiation did not
change practically the shape of spectrum R(ν), which
testified that the orientation of the textured ZnO layers is
the same as in the substrate. The curve 3 of Fig. 2 was
calculated for free film of zinc oxide with the thickness
d = 0.1 µm. The peak of the curve is at the frequency
412 сm–1 at R(ν) = 0.47.
In Fig. 3, the spectra of infrared reflection of
ZnO/Al2O3 structure at the orientation E⊥C are
presented. The curve 1 corresponds to R(ν) when the
thickness of ZnO layer d = 0.5 µm. In the spectrum, there
is a minimum of reflection at the frequency 510 сm–1
(curve 1) and two bends near 430 and 600 сm–1, while
when modeling the ZnO/Al2O3 structure, minima of R(ν)
are at the frequencies 325, 427, 491 and 515 сm–1
(curve 2).
The maxima of R(ν) are located at the frequencies
432 and 600 сm–1, here a curve fluently diminishes R(ν)
into the area of higher frequencies. The calculated R(ν)
(curve 2) is determined for the following parameters of
ZnO layer: d = 0.5 µm, νTO⊥ = 412 сm–1, γf⊥ = 15 сm–1,
νp⊥ = 400 сm–1, γp⊥ = 870 сm–1. On the curve 3, the
theoretical spectrum of R(ν) of free ZnO film is shown at
the parameters above indicated. The maximum
R(ν) = 0.76 is at the frequency 415 сm–1.
As seen from Fig. 3, the presence in ZnO films of
free charge carriers (electrons) of the order of n0 =
1018…1019 cm–3 substantially deforms the spectrum of
reflection in the area between 400 and 1000 сm–1. The
reflection coefficient at the frequency 680 сm–1
diminishes to 0.8 at the presence of the minimum 0.4 at
the frequency 510 сm–1.
The change of position of the doped zinc oxide
films on Al2O3 substrate in the plane ху practically does
not change the shape of R(ν) spectrum, which testifies
isotropy of optical and electrophysical properties of the
investigated system. In addition, it is possible to assert
that the optical axis of the textured layers of zinc oxide
and sapphire is normal to the plane of ху (С⊥ху).
For the concentration of free charge carriers
n0 > 5·1017 сm–3, there is decreasing the reflection
coefficient at the frequencies higher than 700 сm–1. On
the basis of analysis of the studied ZnO/Al2O3 structures,
it is found that in our case the zinc oxide layers have the
following values of the electron concentration n0 =
(1.6…2.8)·1018 cm–3, mobility µ = 1.1…3.1 cm2/(V·s) and
conductivity within the range σ0 = 110…200 Ohm–1·сm–1.
In Fig. 4, the calculated dependences R(ν) of
MgO/Al2O3 structure on the thickness of magnesium
oxide film are presented. The curves 2 to 4 correspond to
the thickness 0.1, 0.25, 0.5 µm at γf⊥ = 12 сm–1. The
increase of the film thickness to 0.5 µm results in the
considerable increase of R(ν) values in the area close to
500 сm–1. Within the frequency range from 450 to
580 сm–1, there is a change of R(ν) from 0.18 for d =
0.1 µm (curve 2) to 0.45 for d = 0.5 µm (curve 4). The
curve 1 was calculated for the Al2O3 single crystal for
parameters indicated in Table 1. The change of film
thickness from 0.1 to 0.5 µm at the unchanged mutually
agreed parameters for magnesium oxide is not
accompanied by changes in the spectrum of reflection
within the range 600…1200 сm–1.
Fig. 4. Calculation spectra R(ν) of the MgO/Al2O3 structure:
2–4 – calculation of R(ν) at νTO⊥ = 416 сm–1 and γf⊥ = 12 сm–1,
d = 0.1 – 0.5 µm; 1 – calculation of R(ν) for Al2O3 (without film).
3 7 11
00
0.5
1
ν, cm–1
R(ν)
1 2 3
0
400 600 1000
0.4
1.0
R(ν)
800
0.6
3
1
2
1
4
4 4
ν, cm–1 0
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
421
Fig. 5. Calculated spectra R(ν) of the MgxZn1–xO/Al2O3
structure: 1 – x = 0.47; 2 – x = 0.60 at d = 2 µm.
Fig. 5 shows the dependence of R(ν) of the
MgхZn1-хO/Al2O3 structure at х = 0.47 (curve 1) and
х = 0.6 (curve 2) with the film thickness 2 µm. This
calculation was performed using the Kramers–Kronig
relations and data [25] and presented in Table 3. The
values of static dielectric constant listed in Table 3 were
determined by the authors of this paper with the use of
the Lidden−Sax−Teller relation. The obtained results are
well agreed with the data presented in the plot of the
work [25]. As it is obvious from comparison of the
curves 1 and 2, the increase of Mg content in the
MgхZn1–хO/Al2O3 structure from x = 0.47 (curve 1) up to
0.60 (curve 2) is accompanied by changes in the
spectrum of external reflection at the frequencies of
“residual rays” of zinc oxide and magnesium oxide.
The most essential changes are observed
accordingly in the ranges 650…750 and 900…1100 сm–1,
which is caused by the frequencies of transversal and
longitudinal optical phonons in the investigated
materials. In turn, it indicates the possibility to develop
practical modulators for the infrared spectral range.
Fig. 6 shows the dependence of R(ν) of the
MgхZn1-хO/Al2O3 structure on the thickness of
MgхZn1-хO film. The curves 1 to 3 correspond to the
thickness 1, 0.5, 0.25 µm. The calculation was performed
with the parameters presented in Table 3. As seen from
the figure, the increase of film thickness from 0.25 to
1 µm results in the considerable increase of R(ν) in the
whole range of “residual rays”. At the frequency
525 сm-1, there is a change of R(ν) from 0.59 for d = 0.25
to 0.92 for d = 1 µm, for the frequency 726 сm–1 the
increase of R(ν) is observed from 0.63 for d = 0.25 µm to
Fig. 6. Theoretical spectra of reflection R(ν) of the
MgxZn1-xO/Al2O3 structure at х = 0.47: d = 1, 0.5, 0.25 µm (1–3).
0.77 for d = 1 µm. Most essential changes from 0.08 to
0.4 were registered at the frequency 940 сm–1.
4. Conclusions
Thus, obtained in this work by using the method of
infrared spectroscopy of external reflection are optical
characteristics of thin films of ternary alloys MgxZn1–xO
on the Al2O3 dielectric substrate in the area of “residual
rays” of film and substrate. It has been shown that the
changes in film thickness and content of Mg substantially
deform the spectrum of reflection in the area of “residual
rays” of film and substrate, decrease reflection ability.
The computer experiment of infrared spectra allowed to
determine the static dielectric constant of MgxZn1–xO
structure at the different x values for the orientation Е⊥С.
It is found that the MgхZn1–хO/Al2O3 structures is well
modeled with using the mutually agreed parameters
presented in Tables 1 to 3, for the single crystals of
magnesium oxide, zinc oxide and leicosapphire for the
orientation Е⊥С, which confirms perspectives of the non-
destructive method of infrared spectroscopy for
determination of optical characteristics of films of ternary
alloys and rate of their texturing.
Acknowledgement
The work was carried out within the framework of theme
No 89452 “Influence of doping on structural, optical and
electron-phonon properties and stability of anisotropic
crystals” with financial support of the Ministry of
Education and Science of Ukraine.
Table 3. Parameters of the investigated samples.
Sample ε∞ ε0
νТО1,
cm–1
νLО1,
cm–1
�S1
γf1,
cm–1
νТО2,
cm–1
νLО2,
cm–1
�S2
γf2,
cm–1
νТО3,
cm–1
γf3,
cm–1
Mg0.47Zn0.53O/Al2O3 3.3 7.06 385 386 1.5 5.0 436 636 15 20 730 40
Mg0.47Zn0.53O/Al2O3 3.1 7.88 389 395 0.8 9.0 447 702 7.0 10 728 20
400 600 1000
0.4
1.0
ν, cm–1
R(ν)
0
800
0.6 1
1 2 2 1
2
400 600 1000
0.4
1.0
ν, cm–1
R(ν)
0
800
0.6
1
1 2
2
1
2
3
3
3
3
1
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
422
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Authors and CV
Venger Yevgen Fedorovich. Doctor
of Physics and Mathematics Sciences,
Professor, Corresponding Member of
the National Academy of Sciences of
Ukraine, Department of Physical and
Technical Problems of Energetics.
His scientific works are devoted to
semiconductor electronics and opto–
elec–tronics. He is one of the foun–
ders of the polariton optoelectronics direction.
Ye.F. Venger has more than 500 publications, 40 patents,
24 textbooks and manuals. The area of scientific interests
includes physics and technology of semiconductor
materials, hetero- and hybrid structures and devices (thin-
film solar cells, photoresistors, new types of photo-
converters, in particular, efficient, wide-band and
selective short-wave radiation sensors, etc.), as well as
analysis, diagnostics, modeling and forecasting the
physical processes in different objects.
Head of the Department of Semiconductor
Heterostructures at the V. Lashkaryov Institute of
Semiconductor Physics, NAS of Ukraine.
E-mail: vengeref@gmail.com
SPQEO, 2018. V. 21, N 4. P. 417-423.
Venger E.F., Venger I.V., Korsunska N.O., et al. Optical properties of ternary alloys MgZnO in infrared spectrum
423
Venger Iryna Vsevolodivna
Researcher at the Department of
Physical and Technological
Foundations of Sensor Material
Science at the V. Lashkaryov Institute
of Semiconductor Physics of the
National Academy of Sciences of
Ukraine. The author of over 30
publications, 4 textbooks and manuals. The area of her
scientific interests includes modeling the optical and
electrophysical properties in polar optically-isotropic and
anisotropic semiconductors and structures on their basis.
E-mail: vengeriv@nas.gov.ua
Korsunska Nadiya Ovsiyivna.
Doctor of Physics and Mathematics,
Professor, Laureate of the State Prize
of the Ukrainian SSR.
Her scientific works are devoted to
the study of recombination and
electronically stimulated diffusion
processes and defect drift processes in
semiconductors and dielectrics, as well as processes of
degradation of materials and devices. The area of
scientific interests covers physics and technology of
semiconductor materials, including nanostructured
materials. The author of more than 300 scientific works,
7 author’s certificates and 2 patents in the field of
semiconductor and dielectric physics.
Leading researcher at the V. Lashkaryov Institute of
Semiconductor Physics, NAS of Ukraine.
E-mail: Korsunska@ukr.net
Melnichuk Liudmyla Yuriyivna
Candidate of Physical and
Mathematical Sciences, Associate
Professor, Excellence in Education of
Ukraine.
In 1996 she defended her Ph.D. thesis
“Anisotropy of surface plasmon-
phonon polaritons in single crystals of zinc oxide” by the
specialty “Solid State Physics”. In April 1998, she was
awarded the title of Associate Professor. She is the author
of more than 120 scientific and methodological works in
the area of physics of semiconductors and dielectrics,
solid state physics, problems of higher education.
Head of the Department of Physics, at the Mykola Gogol
Nizhyn State University.
E-mail: lyu.melnichuk@gmail.com
Melnichuk Olexander
Volodymyrovych Doctor of Physical
and Mathematical Sciences,
Professor, Excellence in Education of
Ukraine. In 2001 he defended his
doctoral dissertation “Surface
Plasmon-Phonon Excitements in
Univalent Semiconductors ZnO and
6H-SiC and Structure Based on them” in the area of
“Physics of Semiconductors and Dielectrics”. In April
2002, he was awarded the title of professor. He is the
author of over 300 scientific and methodological works
in the area of physics of semiconductors and dielectrics,
solid state physics, mathematical modeling, problems of
higher and secondary schools.
Vice-Rector for Scientific and International Relations at
the Mykola Gogol Nizhyn State University.
E-mail: mov310310@gmail.com
Khomenkova Larisa Yuriyivna
Candidate of Physics and
Mathematics, Senior Researcher. The
main area of activity is creation of
multifunctional composite materials
and study of their properties for
applying in microelectronics and light
emitting devices. She is the author of
more than 150 scientific publications in the area of solid
state physics.
Senior Researcher at the V. Lashkaryov Institute of
Semiconductor Physics, NAS of Ukraine.
E-mail: khomen@ukr.net
|
| id | nasplib_isofts_kiev_ua-123456789-215316 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1560-8034 |
| language | English |
| last_indexed | 2026-03-23T18:47:22Z |
| publishDate | 2018 |
| publisher | Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| record_format | dspace |
| spelling | Venger, E.F. Venger, I.V. Korsunska, N.O. Melnichuk, L.Yu. Melnichuk, O.V. Khomenkova, L.Yu. 2026-03-12T08:53:19Z 2018 Optical properties of ternary alloys MgZnO in the infrared spectrum / E.F. Venger, I.V. Venger, N.O. Korsunska, L.Yu. Melnichuk, O.V. Melnichuk, L.Yu. Khomenkova // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 417-423. — Бібліогр.: 25 назв. — англ. 1560-8034 PACS: 78.20.Ci, 78.40.-q https://nasplib.isofts.kiev.ua/handle/123456789/215316 https://doi.org/10.15407/spqeo21.04.417 Properties of thin films of ternary alloys MgₓZn₁₋ₓO on the optically anisotropic Al₂O₃ substrates in the area of “residual rays” of film and substrate are first investigated using the method of infrared spectroscopy and dispersion analysis of reflection coefficients. It was established that the changes in the thickness of the film and the content of Mg substantially deform the spectrum of reflection in the area of “residual rays” of the film and the substrate, decreasing the reflectivity. First, by means of Kramers–Kronig relations with the use of the method of dispersion analysis of infrared reflection spectra, the static dielectric constant of MgₓZn₁₋ₓO structure has been obtained at different values of х, when orientation is Е⊥С. It was ascertained that the MgₓZn₁₋ₓO/Al₂O₃ structures are well modelled when using the mutually agreed parameters, obtained earlier for the single crystals of magnesium oxide, zinc oxide, and leicosapphire at the orientation Е⊥С. It was theoretically shown and experimentally grounded that the assurance of the obtained optical parameters of MgₓZn₁₋ₓO films by the non-destructive method of infrared spectroscopy in the wide spectral range. The obtained results are well in agreement with the literature data. The work was carried out within the framework of theme No 89452 “Influence of doping on structural, optical, and electron-phonon properties and stability of anisotropic crystals” with financial support of the Ministry of Education and Science of Ukraine. en Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України Semiconductor Physics Quantum Electronics & Optoelectronics Optics Optical properties of ternary alloys MgZnO in the infrared spectrum Article published earlier |
| spellingShingle | Optical properties of ternary alloys MgZnO in the infrared spectrum Venger, E.F. Venger, I.V. Korsunska, N.O. Melnichuk, L.Yu. Melnichuk, O.V. Khomenkova, L.Yu. Optics |
| title | Optical properties of ternary alloys MgZnO in the infrared spectrum |
| title_full | Optical properties of ternary alloys MgZnO in the infrared spectrum |
| title_fullStr | Optical properties of ternary alloys MgZnO in the infrared spectrum |
| title_full_unstemmed | Optical properties of ternary alloys MgZnO in the infrared spectrum |
| title_short | Optical properties of ternary alloys MgZnO in the infrared spectrum |
| title_sort | optical properties of ternary alloys mgzno in the infrared spectrum |
| topic | Optics |
| topic_facet | Optics |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/215316 |
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