The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films
To create technology for the preparation of CdS and CdTe thin films by direct current magnetron sputtering, the influence of physical and technological condensation modes on the crystal structure and optical properties of these films was investigated. The laboratory method of DC magnetron sputtering...
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
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| Zitieren: | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films / G.S. Khrypunov, G.I. Kopach, M.M. Harchenko, A.І. Dobrozhan // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2017. — Т. 20, № 2. — С. 262-267. — Бібліогр.: 10 назв. — англ. |
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| author | Khrypunov, G.S. Kopach, G.I. Harchenko, M.M. Dobrozhan, A.І. |
| author_facet | Khrypunov, G.S. Kopach, G.I. Harchenko, M.M. Dobrozhan, A.І. |
| citation_txt | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films / G.S. Khrypunov, G.I. Kopach, M.M. Harchenko, A.І. Dobrozhan // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2017. — Т. 20, № 2. — С. 262-267. — Бібліогр.: 10 назв. — англ. |
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| description | To create technology for the preparation of CdS and CdTe thin films by direct current magnetron sputtering, the influence of physical and technological condensation modes on the crystal structure and optical properties of these films was investigated. The laboratory method of DC magnetron sputtering with preheating of the target for the mentioned films on glass substrates was developed. We obtained the CdS layers with a hexagonal structure 150…200 nm thick under conditions when the plasma discharge current density was 1.1 mA/cm² and the deposition rate – 30…40 nm/min. The bandgap in the obtained CdS films is Eg = 2.38…2.41 eV. After annealing in vacuum, the optical transparency of CdS films reaches 80…90%, which allows the use of these films as a transparent window layer in solar cells based on heterojunctions of CdS/CdTe. When the plasma discharge current density is 2.2…5.4 mA/cm², and the deposition rate is 200 nm/min, we obtained CdTe layers with a hexagonal structure up to 5 µm thick. The transmittance of CdTe films with a hexagonal structure in the wavelength range of the visible spectrum is up to 5%, and in the infrared spectral range is about 60%. The bandgap in the obtained CdTe layers of different thickness is 1.52…1.54 eV. After chloride treatment as a result of the phase transition wurtzite–sphalerite, the investigated CdTe films contain only the stable cubic structure and can be used as a base layer of solar cells.
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Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
262
PACS 81.05.Dz, 81.15.Cd
The influence of physical and technological magnetron sputtering
modes on the structure and optical properties of CdS and CdTe films
G.S. Khrypunov, G.I. Kopach, M.M. Harchenko, A.І. Dobrozhan
National Technical University “Kharkіv Polytechnic Institute”
21, Kirpichov str., 61002 Kharkiv, Ukraine
E-mail: gkopach@ukr.net
Abstract. To create technology for preparation of CdS and CdTe thin films by direct
current magnetron sputtering, the influence of physical and technological condensation
modes on the crystal structure and optical properties of these films were investigated.
The laboratory method of DC magnetron sputtering with preheating of the target for the
mentioned films on glass substrates was developed. We obtained the CdS layers with
hexagonal structure 150…200 nm thick under conditions when the plasma discharge
current density was 1.1 mA/cm2 and the deposition rate – 30…40 nm/min. The bandgap
in the obtained CdS films is Eg = 2.38…2.41 eV. After annealing in vacuum, the optical
transparence of CdS films reaches 80…90%, which allows to use these films as a
transparent window layer in solar cells based on heterojunctions of CdS/CdTe. When the
plasma discharge current density is 2.2…5.4 mA/cm2 and the deposition rate is
200 nm/min, we obtained CdTe layers with hexagonal structure up to 5 µm thick. The
transmittance of CdTe films with hexagonal structure in the wavelength range of the
visible spectrum is up to 5%, and in the infrared spectral range is about 60%. The
bandgap in the obtained CdTe layers of different thickness is 1.52…1.54 eV. After
chloride treatment as a result of the phase transition wurtzite–sphalerite, the investigated
CdTe films contain only the stable cubic structure and can be used as a base layer of
solar cells.
Keywords: cadmium telluride, cadmium sulfide, direct current magnetron sputtering,
thin films.
Manuscript received 10.02.17; revised version received 18.04.17; accepted for
publication 14.06.17; published online 18.07.17.
1. Introduction
Thin-film solar cells based on cadmium sulfide
(CdS)/cadmium telluride (CdTe) heterojunction are
prospective for industrial production [1-3]. In
heterosystems n-CdS/p-CdTe, the CdS layer is used as the
window one. It allows to reduce a negative impact of
surface recombination of non-equilibrium charge carriers
by removing their active generation area from the
illuminated surface. One of the economical and high-tech
methods for thin films is magnetron sputtering [4].
Implementation of the radio-frequency magnetron
sputtering regime for CdS and CdTe films allows to
prevent accumulation of the excess electric charge on the
surface of the target. But this method is expensive, energy
intensive and requires a special technological equipment.
Ukrainian electronic industry mastered the high-tech and
economical method of direct current magnetron sputtering
(DC magnetron sputtering) of materials. However, there
are some technological problems during deposition of
semiconductor films by this method. They are caused by
low conductivity of CdS and CdTe pressed powder targets
and sufficiently low emission ability of these materials.
Therefore, the development of DC magnetron sputtering
of semiconductors and the study of crystal structure and
optical properties of CdS and CdTe films grown under
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
263
different physical and technological modes of conden-
sation are relevant.
2. Experiments
In laboratory technology for condensation of CdS and
CdTe films by using DC magnetron sputtering, it was
used the design of VUP-5m magnetron, which feature
was that the cooling circuit covered only the magnetic
system with the result that there was no forced cooling
of the sputtered semiconductor pressed powder target.
To implement the process of thermionic emission of
electrons from the target material for plasma discharge
ignition, the target was preheated for 10…15 min.
CdS films were condensed on soda-lime glass
substrates at different physical and technological modes:
substrate temperature Тsub = 120…200 °С, pressure of
inert gas РAr = 0.9…1 Pa, magnetron discharge current
density J = 1.1 mA/cm2, the voltage on magnetron
V = 550…600 V, deposition time 5 min. When manufac-
turing CdS/CdTe based solar cells, the base CdTe layer
is condensed on CdS layer at Tsub > 300 °C. The effect of
annealing in vacuum 10-4 Pa at 400…420 °C for 30 min
on the structure and optical properties of CdS layers was
investigated.
CdTe layers were also obtained on soda-lime glass
substrates under the following conditions: Тsub =
295…315 °С, РAг = 0.8…1 Pa, J = 2.2…5.6 mA/cm2,
V = 600…650 V, deposition time 15…25 min. To
determine the effect of heat treatment on the structure of
CdTe samples, the CdTe layers annealing was carried
out in vacuum at Т = 400 °С for 20 min.
To use the obtained CdTe films as base layers of
solar cells, there was performed chloride treatment (Cl
treatment) in vacuum Р = 5.3·10-3 Pa and temperature of
CdCl2 evaporator 470…475 °С for 5 min with
subsequent annealing in air at T = 430 °С for 25 min [5].
The structure of the obtained CdTe and cadmium
sulfide films was studied using the X-ray diffractometry
(XRD) methods [6]. There was performed automatic
recording of X-ray spectra at θ-2θ scanning by using X-
ray diffractometer DRON-4 with the step
0.01…0.02 degrees in Kα-radiation of cobalt anode.
To accurately determine the phase composition of
the obtained CdTe films, we used the “oblique” shooting
method, during which in the radiation of cobalt anode in
the process of θ-2θ scanning performed were detection
and registration of diffraction reflections from those
sphalerite and wurtzite planes that are not detected in the
foregoing registration method because of texturing of
samples.
The CdTe cubic structure lattice parameter was
determined using the formula:
222 lkhda ++= , (1)
where d is the interplanar spacing.
For precise determination of the lattice parameter,
the Nelson–Rhyl extrapolation method was used.
Optical studies of CdTe and CdS layers were
carried out using the spectrometer SF-2000. The trans-
mission spectrum of studied films was used to determine
the thickness of the layers according to [7]. The thick-
ness of the layers was determined using the formula:
( ) ( )( )1221
21
2 λ⋅λ−λ⋅λ
λ⋅λ⋅
=
nn
M
t , (2)
where λ1, λ2 are the wavelengths of two adjacent
extremums (interferential maxima or minima of
transmission spectrum) in nm; n (λ1), n (λ2) – refractive
index, depending on the wavelengths λ1, λ2.
The bandgap of thin films was determined by
calculating the dependence of absorption coefficient on
the wavelength α(λ) using [8]:
( ) teRT ⋅α−⋅−= 1 , (3)
where T is the transmission coefficient; R – reflection
coefficient; t – film thickness.
The bandgaps of CdTe and CdS polycrystalline
films were determined by extrapolation of the linear
portion of the (α·hν)2 = f (hν) curves (where h – Planck
constant, ν – frequency) to the intersection with the hν
energy axis.
3. Results and discussion
When studying the XRD patterns of the lattice of CdS
layers grown at different substrate temperatures Тsub =
120…200 °С (Fig. 1), the only one diffraction peak was
observed for all of the received films at the angle
2θ = 30.62°. This peak corresponds to reflection (111) of
cubic structure or (002) hexagonal phase of CdS. A low
intensity of this peak is caused by a small thickness of
the sample. It does not allow to accurately determine the
phase composition of the CdS samples using the XRD
methods.
But considering that the CdS stable structure is
hexagonal [9], subsequent diffractogram data processing
(Table 1) was done for this CdS phase. For all the
samples, the intensity of peak lies in the 220-280 imp/s
range, which indicates almost the same thickness of
obtained CdS layers. The estimated values of interplanar
spacing lie in the 3.379…3.391 Ǻ range, which
corresponds to the value of lattice parameter с =
6.758…6.782 Ǻ. The obtained values of the parameter с
are bigger than the table value for single crystals (c =
6.7198 Ǻ, PCPDFWIN# 411049) and indicate the
presence of macrostresses. The full width at half
maximum (FWHM) of the peaks in the 0.3…0.38 degree
range on the 2θ scale are typical for CdS thin layers
obtained using vacuum methods [10] and caused by
small grain sizes of the film.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
264
Fig. 1. XRD patterns of the obtained СdS sample layer (a) and
after its annealing (b).
Spectral dependences of transmission coefficient for
the obtained CdS layers are presented in Fig. 2. According
to results of optical studies there is a strong absorption of
radiation in the wavelength range 400 to 500 nm, while in
the infrared spectral range the CdS films transparence is
up to 80%. The typical thickness of investigated CdS
layers is 150…200 nm. The bandgap in the prepared CdS
films is Еg =2.38…2.41 еV, which is close (Еg =
2.42…2.45 еV) to that of СdS single crystals.
After annealing of CdS layers in vacuum, in the
XRD pattern (Fig. 1b) only one intense peak was
detected at the angle 2θ = 32.8°, which corresponds to
reflection (101) of stable CdS hexagonal phase. The
optical transparence of CdS films is up to 90% over the
entire spectral range, which indicates the ability to use
these films as a transparent window layer in solar cells
based on heterostructure of CdS/CdTe [10].
We investigated the structure and optical properties
of CdTe thin films grown on glass substrates using DC
magnetron sputtering method at different physical and
technological condensation modes (Table 2).
The typical XRD patterns of СdTe sample layers
obtained at different physical and technological
condensation modes (samples 3, 4, 6, 7) are shown in
Fig. 3 (by the example of sample 6).
In all diffractograms of the studied CdTe films,
there are two distinct peaks at the angles 2θ 27.05° and
91.05°. According to the table ASTM 15-0770, they can
belong both to hexagonal and cubic structures of CdTe:
wurtzite reflections (002) and (006) and sphalerite
reflections (111) and (333), respectively. Also, the
reflections (103) and (105) of hexagonal phase CdTe are
observed in diffractograms.
Table 1. CdS films diffractograms processing results.
Sample № Тsub, °С Peak position, degrees Interplanar spacing, Å Intensity, imp/s FWHM, degrees
2 120 30.62 3.388 216 0.33
3 130 30.59 3.391 280 0.33
1 150 30.58 3.391 44 0.38
4 175 30.63 3.386 260 0.30
6 180 30.64 3.385 269 0.34
5 200 30.70 3.379 234 0.30
Table 2. Technological modes of obtaining CdTe films.
№ Тsub at start, С Тsub at finish, С t, min РAг, Pa U, V I, mА
1 330 315 15 0.8–1 600 60
2 300 300 15 0.8–1 600 40
3 295 292 25 0.8–1 600 40
4 300 300 25 0.8–1 600 60
5 270 315 15 0.9–1 600 80
6 312 295 25 0.9–1 650 80
7 312 297 15 0.8–0.9 650 100
8 300 316 25 0.9–1 600 80
9 300 313 25 0.9–1 600 80
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
265
Fig. 2. Spectral dependences of the transmission coefficient for
the samples 1 to 6, respectively.
Fig. 3. Typical XRD patterns of the obtained СdTe films:
(a) sample 6, (b) sample 6, by using the “oblique” shooting
method.
Using the “oblique” shooting method of
diffractometry at the angles 2θ 72° to 85° allowed
determining the exact phase composition of grown CdTe
layers when rotating the sample by the angle 20.5°. In all
diffractograms, only the reflection (105) of hexagonal
phase was observed (Fig. 3b). Thus, all the studied CdTe
films obtained in different physical and technological
condensation modes by DC magnetron sputtering
method contain only metastable hexagonal structure.
The annealing of samples in vacuum at Т = 400 °С for
20 min does not change the CdTe layers phase.
Traditional Cl treatment of the studied CdTe films
facilitates phase transition wurtzite–sphalerite, what can
be seen in XRD patterns. The typical diffractogram of
the sample 8 (Table 2) is shown in Figs. 4a and 4b.
All peaks that belong to the stable cubic structure
CdTe are observed. Using the “oblique” shooting
method at the angles 2θ 72.5…87.5°, when rotating the
sample by the angle 20.5°, it was found that, in this area
of XRD pattern, only cubic structure peaks (331) and
(422) can be observed, hexagonal structure peaks (105)
are not presented. Thus, Cl treatment facilitates phase
transition wurtzite–sphalerite, thereby studied CdTe
films contain only stable cubic structure.
Fig. 4. XRD pattern of the sample 8: (a) after Cl treatment and
annealing in air and (b) by using the “oblique” shooting
method.
After Cl treatment, we observed a slight decrease
of FWHM values of peaks (111) and (333) as compared
with the peaks (002) and (006) of hexagonal phase in the
samples before Cl treatment and annealing in air (Figs. 1
and 4). This indicates the passing of the recrystallization
process and grain size increasing in the polycrystalline
CdTe films. The calculated value of lattice parameter in
the cubic structure of CdTe films after Cl treatment is
а = 6.4905 Å. The deviation from the value а in the table
ASTM 15-0770 is less than 0.2%.
Spectral dependences of the transmission
coefficient for CdTe film samples 1-9 are shown in
Fig. 5 (Table 2).
For all the samples, there is a strong absorption of
radiation within the wavelength range 400…700 nm and
sharp fall at the band edge within the range
750…800 nm. In the infrared spectral range, the
transparence of films 4 and 5 is about 65%, films 2 and 3
is about 50%, films 1, 6, 8 and 9 is about 30%.
Fig. 5. Spectral dependences of the transmission coefficient for
the samples 1 to 9.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
266
Table 3. The value of the bandgap for CdTe films of different thicknesses.
№ t, min I, mА Т, С Film thickness, nm Еg, еV
1 15 60 315 300 1.51
2 15 40 300 390 1.53
3 25 40 292 1030 1.51
4 25 60 300 2360 1.5
5 15 80 315 2120 1.52
6 25 80 300 5200 1.52
7 15 100 297 5500 –
8 25 80 316 4900 1.54
9 25 80 312 5000 1.53
The obtained results for the film thickness and
bandgap based on optical researches are presented in
Table 3.
Being based on the calculated values of the CdTe
film thickness that differs by the condensation time, the
condensation rate that depends on the plasma discharge
current was calculated (Fig. 6).
The average deposition rate of CdTe films
increases with increasing the plasma discharge current
regardless of the condensation time. Increasing the slope
of the plot areas at a discharge current higher than
60 mA indicates that the chosen magnetron operation
mode provides sufficiently high increasing the film
deposition rate. The fact, that when the condensation
time is 25 min, the average deposition rate of film is
higher than in the case t = 15 min, is caused by the
simultaneous occurrence of two processes: target
sputtering and increasing its material sublimation rate
with an increase of its temperature due to Ar ions
bombing. When the plasma discharge current was
>80 mА, it was got the high enough rate of condensation
reaching the level 150…200 nm/min. At identical
operating parameters of the magnetron and Ar pressure
in vacuum chambers, the relative difference of CdTe
films thickness is lower than 2% (Table 1, samples 6, 8
and 9).
Fig. 6. Dependence of the average CdTe film deposition rate on the discharge current in the mentioned modes for
condensation time 15 (1) and 25 (2) minutes.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2017. V. 20, N 2. P. 262-267.
doi: https://doi.org/10.15407/spqeo20.02.262
© 2017, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
267
4. Conclusions
The laboratory method of DC magnetron sputtering with
preheating of the target for CdS and CdTe films on soda-
lime glass substrates was developed. The CdS layers
with hexagonal modification 150…200 nm thick under
conditions when the plasma discharge current density is
1.1 mA/cm2. The deposition rate 30…40 nm/min was
obtained. The bandgap in these CdS films is Eg =
2.38…2.41 eV. After annealing in vacuum, the optical
transparence of CdS films is 80…90%, which allows to
use these films as a transparent window layer in solar
cells based on the heterostructure CdS/CdTe.
When the plasma discharge current density is
2.2…5.4 mA/cm2 and the deposition rate is 200 nm/min,
CdTe layers with hexagonal structure up to 5 µm thick
were obtained. The transmittance of CdTe films with the
hexagonal structure in the wavelength range of the
visible spectrum is up to 5%, and in the infrared spectral
range is about 60%. The bandgap in the obtained CdTe
layers of different thickness is 1.52…1.54 eV.
After Cl treatment with subsequent annealing in air
at T = 430 С for 25 min, as a result of the phase
transition wurtzite–sphalerite, the investigated CdTe
films contain only the stable cubic structure, which value
of the lattice parameter is а = 6.4905 Å, which by less
than 0.2% deviates from the tabular value. These CdTe
films can be used as a base layer of CdS/CdTe based
solar cells.
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236–241.
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|
| id | nasplib_isofts_kiev_ua-123456789-214920 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1560-8034 |
| language | English |
| last_indexed | 2026-03-20T13:04:06Z |
| publishDate | 2017 |
| publisher | Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| record_format | dspace |
| spelling | Khrypunov, G.S. Kopach, G.I. Harchenko, M.M. Dobrozhan, A.І. 2026-03-04T12:47:24Z 2017 The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films / G.S. Khrypunov, G.I. Kopach, M.M. Harchenko, A.І. Dobrozhan // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2017. — Т. 20, № 2. — С. 262-267. — Бібліогр.: 10 назв. — англ. 1560-8034 PACS 81.05.Dz, 81.15.Cd https://nasplib.isofts.kiev.ua/handle/123456789/214920 https://doi.org/10.15407/spqeo20.02.262 To create technology for the preparation of CdS and CdTe thin films by direct current magnetron sputtering, the influence of physical and technological condensation modes on the crystal structure and optical properties of these films was investigated. The laboratory method of DC magnetron sputtering with preheating of the target for the mentioned films on glass substrates was developed. We obtained the CdS layers with a hexagonal structure 150…200 nm thick under conditions when the plasma discharge current density was 1.1 mA/cm² and the deposition rate – 30…40 nm/min. The bandgap in the obtained CdS films is Eg = 2.38…2.41 eV. After annealing in vacuum, the optical transparency of CdS films reaches 80…90%, which allows the use of these films as a transparent window layer in solar cells based on heterojunctions of CdS/CdTe. When the plasma discharge current density is 2.2…5.4 mA/cm², and the deposition rate is 200 nm/min, we obtained CdTe layers with a hexagonal structure up to 5 µm thick. The transmittance of CdTe films with a hexagonal structure in the wavelength range of the visible spectrum is up to 5%, and in the infrared spectral range is about 60%. The bandgap in the obtained CdTe layers of different thickness is 1.52…1.54 eV. After chloride treatment as a result of the phase transition wurtzite–sphalerite, the investigated CdTe films contain only the stable cubic structure and can be used as a base layer of solar cells. en Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України Semiconductor Physics Quantum Electronics & Optoelectronics The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films Article published earlier |
| spellingShingle | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films Khrypunov, G.S. Kopach, G.I. Harchenko, M.M. Dobrozhan, A.І. |
| title | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films |
| title_full | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films |
| title_fullStr | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films |
| title_full_unstemmed | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films |
| title_short | The influence of physical and technological magnetron sputtering modes on the structure and optical properties of CdS and CdTe films |
| title_sort | influence of physical and technological magnetron sputtering modes on the structure and optical properties of cds and cdte films |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/214920 |
| work_keys_str_mv | AT khrypunovgs theinfluenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT kopachgi theinfluenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT harchenkomm theinfluenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT dobrozhanaí theinfluenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT khrypunovgs influenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT kopachgi influenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT harchenkomm influenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms AT dobrozhanaí influenceofphysicalandtechnologicalmagnetronsputteringmodesonthestructureandopticalpropertiesofcdsandcdtefilms |