close

Вход

Забыли?

вход по аккаунту

?

2053-1591%2Faa9580

код для вставкиСкачать
Materials Research Express
ACCEPTED MANUSCRIPT
Controlled morphological modifications of ZnO thin films by ion
irradiation
To cite this article before publication: Vidya U Kondkar et al 2017 Mater. Res. Express in press https://doi.org/10.1088/2053-1591/aa9580
Manuscript version: Accepted Manuscript
Accepted Manuscript is “the version of the article accepted for publication including all changes made as a result of the peer review process,
and which may also include the addition to the article by IOP Publishing of a header, an article ID, a cover sheet and/or an ‘Accepted
Manuscript’ watermark, but excluding any other editing, typesetting or other changes made by IOP Publishing and/or its licensors”
This Accepted Manuscript is © 2017 IOP Publishing Ltd.
During the embargo period (the 12 month period from the publication of the Version of Record of this article), the Accepted Manuscript is fully
protected by copyright and cannot be reused or reposted elsewhere.
As the Version of Record of this article is going to be / has been published on a subscription basis, this Accepted Manuscript is available for reuse
under a CC BY-NC-ND 3.0 licence after the 12 month embargo period.
After the embargo period, everyone is permitted to use copy and redistribute this article for non-commercial purposes only, provided that they
adhere to all the terms of the licence https://creativecommons.org/licences/by-nc-nd/3.0
Although reasonable endeavours have been taken to obtain all necessary permissions from third parties to include their copyrighted content
within this article, their full citation and copyright line may not be present in this Accepted Manuscript version. Before using any content from this
article, please refer to the Version of Record on IOPscience once published for full citation and copyright details, as permissions will likely be
required. All third party content is fully copyright protected, unless specifically stated otherwise in the figure caption in the Version of Record.
View the article online for updates and enhancements.
This content was downloaded from IP address 129.16.69.49 on 26/10/2017 at 19:20
us
cri
Controlled morphological modifications of ZnO thin films by
ion irradiation
an
Vidya Kondkar1, Deepti Rukade1, Dinakar Kanjilal2 and Varsha
Bhattacharyya1
1
Department of Physics, University of Mumbai, Mumbai-400098, India.
2
Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi-11006,
India.
E-mail: vidya.kondkar@gmail.com
Abstract. Nanocrystalline thin films of zinc oxide (ZnO) of thickness 100 nm are deposited using
dM
electron beam (e-beam) evaporation technique. These films are irradiated using 75 MeV Au ion
beam at two different fluences namely 11011 ionscm2 and 51011 ionscm2 . GAXRD and Raman
spectroscopic studies indicate stability of nanocrystalline phases of ZnO against irradiation.
Surface morphology studies using atomic force microscopy show evolution of nanosized hillocks
at the surface of the irradiated films. Nano-hillock formation is also confirmed by a blue shift of
the UV-visible absorption edge. The electrical conductivity of the films is found to decreases due
to irradiation induced morphological modifications. Ion irradiation technique has been effectively
used for controlled modification of nanocrystalline ZnO thin film surface. The preliminary studies
carried out clearly indicate that the irradiated films are suitable for various applications.
pte
Keywords: Irradiation, Nano-hillocks formation, Nanocrystalline ZnO.
Submitted toMaterials Research Express
ce
1. Introduction
Zinc oxide (ZnO) is an n-type wide band (3.37 eV) semiconductor with a stable hexagonal wurtzite
crystal structure and exciton binding energy of 60 meV [1]. Being a multifunctional material, ZnO has
attracted scope for extensive research opportunities especially in the fields of optoelectronic devices such
as transparent thin film transistors (TFT), surface acoustic wave devices (SAW), optical wave guide,
piezoelectric devices and physical, chemical, gas and bio-sensing devices [2-7]. ZnO based thin films are
also considered as the best alternative for Indium tin oxide (ITO) thin films as ZnO is non toxic, less
expensive, available in abundance, highly durable against hydrogen plasma and possess excellent
electrical, chemical and optical properties for various applications [8, 9].Use of nanocrystalline ZnO thin
films is dramatically expanding for various applications due to improved performance and efficiency
observed at nanoscale [10]. There are number of research articles emphasizing importance of surface
nanostructures and particle size while considering thin films for device fabrication [11, 12]. Zeng et al has
observed surface morphology of the perovskite (PVSK) solar cells and carrier transporting materials
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
pt
Page 1 of 10
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
dM
an
us
cri
pt
(electron transport layer (ETL) and hole transport material (HTM)) as a crucial factor for determining
performance of the PVSK solar cell. ZnO is considered as one of the typical ETL material for PVSK solar
cells [13]. Son et al has successfully fabricated 11% efficient PVSK solar cells with ETL formed of ZnO
nanorods [14]. Sun et al has shown that catalytic performance of ZnO is also controlled by surface
morphology [15]. In a review, Mende et al has highlighted the strong improvement in electrical properties
results in high sensitivity of ZnO thin films sensors even at room temperature due to availability of high
surface area [10]. Bender et. al has compared performance of ZnO thin films synthesized using different
deposition techniques for ozone detection at room temperature and found excellent improvement in the
sensor performance for the films with nano-sized grains [16]. It is observed that ZnO thin films
constituted of nano-dimensional grains show enhanced gas sensing due to availability of high density of
grain boundaries and interfaces for interaction of gas molecules [11]. Understanding the importance of
surface morphology along with nano-range crystallite size brings requirement of rigorous efforts for
synthesis of nanocrystalline ZnO phases with different surface morphologies.
For ZnO thin films, surface morphology and crystallite size strongly depends on preparation root
[17]. Both, surface morphology and crystallite size carry equal importance for determining device
performance. Various techniques are available for synthesis of nanocrystalline ZnO thin films. Once the
nanosize is approached, it becomes important to have desirable surface morphology of the films. If this
does not happen, altering the surface morphology without any increase in the particle size becomes a
primary requirement. Thermal treatment is one of the techniques that can be used for achieving surface
modifications but it leads to wide size distribution of synthesized nanophases. This can be avoided if swift
heavy ion (SHI) irradiation technique is used for surface modification. SHI irradiation technique comes
with an advantage of controlled modification of the target properties by adjusting ion beam parameters
such as ion species, charged state, fluence and energy [18]. A number of research groups have studied ion
beam induced modifications in thin films but specific use of SHI beam for controlled surface
modifications of ZnO thin film has not been carried out so far.
In the present investigation, we report controlled surface modification of ZnO thin films using
SHI beam. In this study, nanocrystalline ZnO thin films are irradiated with Au ion beam at two different
fluences. Role of ion beam parameters in nano-hillock formation at ZnO thin film surface and its effect
on optical and electrical properties is discussed.
ce
pte
2. Methods
Thin films of ZnO of thickness 100 nm were deposited on fused silica substrates by e-beam evaporation
method. Commercially available ZnO powder (99.5) was sintered at 700 for 7 hours. This powder was
used for preparing pallets. Prepared pellets were again sintered at 700 for 7 hours. Sintered pallets were
used as targets for e-beam evaporation. All the films were deposited simultaneously. The film thickness
was monitored using in situ quartz crystal monitor.
Deposited films were irradiated by 75 MeV Au ions at two different fluencies 11011 ionscm2
and 51011 ionscm2 at room temperature. Irradiation was carried out for 16 s and 80 s for the ion fluence
of 11011 ionscm2 and 51011 ionscm2 respectively. Au ion irradiation was performed using 15 MV
Pelletron facility at IUAC, New Delhi, India. Au ions with charged state 7+ and beam current of 7 nA
were used for irradiation. The range of 75 MeV Au ions calculated using SRIM code is 10.21 um and is
much more than thickness (100 nm) of ZnO films. The rise of 828 K in local temperature during
irradiation of ZnO thin films is calculated using Stefan's equation (refer section 4) [19].
Structural analysis of the thin films before and after irradiation is done by glancing angle X-ray
diffraction using Rigaku Ultima IV X-ray Diffractometer and Raman spectroscopy by Renishaw In-Via
Raman spectrometer. Surface morphology of the films is studied by atomic force microscopy (AFM)
using Veeco di Innova Atomic Force Microscope. Optical properties are studied by absorption
measurement with a UV-VIS double-beam spectrophotometer Varian CARY 5000. The electrical
conductivity is measured by Jandel BM3-AR four-probe system and computing multimeter.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Page 2 of 10
3. Results
D
0.9
 cos
us
cri
3.1GAXRD Analysis:
Structural properties of the films before and after irradiation are studied using GAXRD technique. Figure
1 shows GAXRD patterns of as deposited and irradiated ZnO thin films. All the films are polycrystalline
in nature. Diffraction peaks of zinc oxide with hexagonal wurtzite crystal structure with lattice constant a
= 3.249 Å and c = 5.205 Å (JCPDS card No. - 05-0664) are observed. Presence of the reflections at (100),
(002), (101), (102), (110), (103), (112) and (201) planes in GAXRD spectra indicate polycrystalline
nature of the films.
The crystallite size of the film is calculated using Debye-Scherrer formula,
(1)
pte
dM
an
Here, D is diameter of the particles forming the film,  is the wavelength of Cu K line,  is the full
width half maximum (FWHM) in radians, and  is the Bragg's diffraction angle.
The average crystallite size calculated for pristine and irradiated films using Debye-Scherrer
formula is shown in table 1. Small reduction of 1 nm in crystallite size is observed for the film irradiated
at fluence 51011 ionscm2.
Figure1. GAXRD patterns of ZnO thin films.
ce
3.2Raman Spectroscopy:
Wrutzite ZnO belongs to C46 (P63mc) space symmetry. The primitive cell has 4 atoms with all atoms
occupying 2b sites of symmetry C3. Group theory predicts the existence of the following optical modes
at the  point of the Brillouin zone: opt A1+2B1+E1+2E2. Out of these doubly degenerate B1 modes at
260 and 540 cm-1 are silent. A1, E1, E2 modes are Raman active and A1 and E1 are infrared active, which
therefore split into longitudinal optical (LO) and transverse optical (TO) components. Thus, there are six
Raman active modes with two E2 modes at 101 (low) and 437 cm-1 (high), A1(TO) mode at 381cm-1,
E1(TO) mode at 407cm-1 , A1(LO) mode at 574 cm-1 and E1(LO) mode at 583 cm-1 [20, 21].
The Raman spectra of as-deposited and irradiated ZnO films are shown in figure 2. Various phonon
modes corresponding to wrutzite ZnO structure are observed in the spectra. E2 (low) peak observed in as-
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
pt
Page 3 of 10
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
dM
an
us
cri
pt
deposited as well as irradiated film indicates good crystalline quality of the films. A peak observed near
437 cm-1 is ascribed to E2 (high) mode. Presence of A1 (LO) and E1 (LO) mode confirms wurtzite
structure ZnO. The origin of the peak observed near 227 cm-1 (indicated by #) is attributed to presence of
oxygen vacancies in the films [21]. Presence of a strong mode at 142 cm-1 (indicated by *) is assigned to
vibration of Zn sublattice [22].
pte
Figure2. Raman spectra of the ZnO thin films.
ce
3.3AFM Study:
Surface morphology plays an important role in determining performance of thin film based devices.
Surface of the ZnO thin films is investigated using AFM. Figure 3 shows 2D and 3D AFM images of the
ZnO thin films. Values for average height and RMS roughness are shown in table 1. AFM micrographs of
as-deposited films show bigger grains of approximately 0.5 micron. In case of irradiated films, nanosized hillock like structures are observed at film surface in the direction parallel to the ion beam. Average
height of the hillocks and roughness of the films increases with increase in the ion fluence. At lower ion
fluence formation of interconnected hillocks is observed while at higher fluence separate, monodispersed, uniformly spaced hillocks are observed.
SHI alters surface morphology through formation of cylindrical track. During interactions with
the target SHI deposits huge energy to the target. This leads to sudden target melting. The process goes up
to few picoseconds and a radial temperature gradient is built up around the ion track. Surface tension
gradient is also developed due to melting of the target. Surface tension gradient and pressure gradient
developed push molecules towards surface and mass transport can be seen in the form of hillocks at the
surface [23].
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Page 4 of 10
(b)
(e)
pt
(d)
dM
an
(a)
(f)
ce
pte
(c)
Figure3. 1 m  1 m AFM 2D images of (a) as-deposited film (b) film irradiated with ion fluence
11011 ionscm2 and (c) film irradiated with ion fluence 51011 ionscm2 and AFM 3D image of (d) asdeposited film (e) film irradiated with ion fluence 11011 ionscm2 and (f) film irradiated with ion fluence
51011 ionscm2.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
us
cri
Page 5 of 10
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
pt
It should be noted that the surface roughness and increase in nano-hillock like morphology with increase
in ion fluence provide high surface uniformity that enhances sensitivity and specificity of ZnO thin film
based sensors [2, 18].
us
cri
Table 1. Crystallite size, average height and RMS roughness values for ZnO thin films.
Irradiation fluence
Crystallite size (nm)
Avg. height (nm)
RMS roughness (nm)
as-deposited
11.00±0.30
32.7500±0.7644
8.7214
11011 ioncm2
11.00±0.30
21.7365±0.6732
8.7581
51011 ioncm2
10.00±0.28
52.0916±0.1145
18.3124
dM
an
3.4UV-Vis Spectroscopy:
Figure 4 show optical absorption spectra and energy band gap calculated for ZnO thin films. Optical
absorption in the range 200-800 nm is studied for all the films. In semiconductors, effective band gap
increases with decrease in the particle size and the absorption edge is blue shifted [24].The direct
transition band gap of thin films is calculated using Tauc's plot. For these transitions absorption coefficient is related to band gap Eg by,
 h  A(h  E g
1
)2
(2)
ce
pte
Here, h is the Plank's constant and  is the frequency of incident light. The product h gives energy of
photon. To find the band gap a graph of (h)2 versus h (Tauc’s plot) is plotted. Extrapolating linear
portion of absorption edge at  0 to find intercept with energy axis gives optical band gap.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Page 6 of 10
Figure4. (a) Optical absorption spectra (b) (h)2 versus h plot of ZnO thin films.
Page 7 of 10
us
cri
pt
A small blue shift of 2 and 6 nm is observed in the absorption edge of the irradiated films at ion
fluencies 11011 ionscm2 and 51011 ionscm2 respectively. The energy band gap values calculated from
Tauc’s plot are shown in the figure 4(b). A small increase in the value of band gap indicates no significant
modification in basic crystal lattice of ZnO and increase is observed due to morphological modification
which is also confirmed by GAXRD and AFM studies [25].
3.5Electrical conductivity measurements:
Electrical conductivity of the films is measured using four probe method. Electrical resistivity and
conductivity values measured for ZnO thin films are listed in table 2. Significant decrease in electrical
conductivity is observed for irradiated films. It should also be noted that the conductivity decreases with
increase in ion fluence. Observed decrease in electrical conductivity is attributed to the increase in the
grain boundary scattering that occurs due to nano-hillock formation and growth in irradiated films.
Increase in grain boundaries scattering reduces the electron mobility that in turn decreases conductivity of
the irradiated films [26]. Small decrease observed in the crystallite size of the film irradiated at fluence
51011 ionscm2 also contributes to the decrease in electrical conductivity [25].
an
Table 2. Electrical resistivity and conductivity of ZnO thin films.
Irradiation fluence
Resistivity(cm)
Conductivity (Scm)
as-deposited
0.495
2.020
23.65
dM
11011 ioncm2
51011 ioncm2
35.50
0.0422
0.0281
pte
4. Discussion
In the present investigation, smooth surface of the nanocrystalline as-deposited films is modified using
ion irradiation technique. Ion irradiation of the as-deposited films results in nano-hillock formation and
growth. Irradiation induced morphological modifications change optical and electrical properties of ZnO
thin films. Nano-hillock formation at smooth surface of the nanocrystalline as-deposited films can be
explained with the help of thermal spike model. Due to quick target melting caused by energy transfer
from SHI, a thermal spike is generated in that region. Ion beam induced hillock like structures are
observed at film surface due to mechanical stress from thermal expansion of the target. Hillocks emerge
at the film surface only if the thermal spike energy  is more than a threshold value th [27]. Threshold
value of the spike energy can be calculated using equation
 th  2.7 gSeth
(3)
ce
For ZnO, g = 0.4 [28] and Seth depends on density (), average specific heat (c) of the target and
difference between the melting point of the target and irradiation temperature (To) and is given by [29],
Seth   cToa(0)2 / g  5.94 keVnm
(4)
Value of th calculated is 6.42 keVnm. Thus, the minimum energy required hillock formation is 6.42
keVnm. Therefore, it can be concluded that the energy of the thermal spike generated during Au ion
irradiation is more than 6.42 keVnm and is responsible for observed nano-hillock formation.
At fluence 51011 ionscm2, elongated grains are observed in 2D AFM images. This can be
explained with the help of Audouard's double hit model [30]. Incoming SHI creates disorders along the
ion track formed during passage and leads to isotropic growth of nano-hillocks. At higher ion fluence,
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
dM
an
us
cri
pt
number of ions impinging per unit area is more. This results in increased second ion interactions with
already damaged region. However the film boundaries remain same and act as a growth-constrain. This
results in formation of lengthened particles.
The sudden rise in local temperature (T) occurred due to generation of thermal spike during
irradiation depend on input power of density (Pb), effective emittance of the substrate (), StefanBoltzman constant () and surrounding target temperature (Ts  300 K) and can be calculated using
Stefan's equation [19],
(5)
Pb  (T 4  Ts4 )
The rise in local temperature estimated using above equation is 828 K for ZnO thin films on glass
substrate. This temperature is much higher than optimal temperature required for crystallization of ZnO
thin films [31]. It is also observed that for nanocrystalline semiconductors the melting point decrease
considerably as nanosize is approached [32]. In the present study, nanocrystalline ZnO thin films spend
full irradiation period of 16 s and 80 s for the ion fluence of 11011 ionscm2 and 51011 ionscm2
respectively at this temperature. The local rise in temperature occurred due to thermal spike generated
during irradiation along with nanocrystalline nature of the as-deposited ZnO films are thus responsible for
observed morphological modification [19].
Thus, the morphology of the films is effectively modified by Au ion beam irradiation. Ordered
and uniform ZnO nanostructures formed at film surface in turn modify optical and electrical properties of
thin films. Irradiation induced modification of ZnO thin films permit its use for various applications. As
engineering surface morphology of ZnO thin films is of great interest for manifestation of its tailorable
functions, controlled growth with such ordered and uniform nanostructures is highly desirable and may
show improved performance in nanosensors, solar cells and various optoelectronic devices [10, 33-35].
pte
5. Conclusion
Surface properties of ZnO thin films are modified without altering its structural properties with the help
of ion irradiation technique. GAXRD and Raman spectroscopy studies confirm no change in structural
properties of thin films on irradiation. Ion irradiation results in nano-hillock formation and growth at the
film surface. Average height, length and uniformity of the nano-hillocks formed increase with increase in
the ion fluence. UV-Vis spectroscopic analysis support structural characterization with a small shift
observed due to change in surface morphology. Surface morphology modifications result in considerable
decrease in electrical conductivity in irradiated films. The minimum thermal spike energy required for
nano-hillocks formation at ZnO thin film surface is estimated to be 6.42 keVnm. The rise in local
temperature occurred due to thermal spike generation is calculated using Stefan's equation.
Nanocrystalline nature of the as-deposited ZnO thin films and irradiation induced rise in local
temperature are considered as the factors responsible for observed surface modification. Thus, SHI
irradiation technique has been successfully utilized as a tool for controlled surface modification of ZnO
thin films.
ce
Acknowledgments
Author (V. Kondkar) is grateful to Prof. R. G. Pillay, TIFR, Mumbai, India for thin film deposition
facility. Thanks are due to Dr. Asokan, IUAC, New Delhi, India for his inputs and help rendered during
irradiation experiment. Help rendered by Mr. Ajit Mahadkar, TIFR, Mumbai, India during thin film
deposition is highly acknowledged.
References
[1] Ozgur U, Alivov Y I, Liu C, Teke A, Reshchikov MA, Dogan S, Avrutin V, Cho S J and Morkoc H
2005 A comprehensive review of ZnO materials and devices J Appl Phys. 98 041301.
[2] Fazmir H, Wahab Y, Anuar A F M, Zakaria M R, Najmi M, Johari S, Mazalan M and Arshad M K
2014 Characterization of ZnO thin film as piezoelectric for biosensor applications Conf. Proce.
Sensors and Applications 1-6.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Page 8 of 10
Page 9 of 10
ce
pte
dM
an
us
cri
pt
[3] Fortunato E, Goncalves A, Pimentel A, Barquinha P, Ferreira G, Pereira L, Ferreira I and Martins R
2009 Zinc Oxide , a Multifunctional Material : From Material to Device Applications Appl. Phys. A
96 197–205.
[4] Gaspar D, Pereira L, Gehrke K, Galler B, Fortunato E and Martins R 2017 High Mobility
Hydrogenated Zinc Oxide Thin Films Sol. Energy Mater Sol. Cells 163 255–62.
[5] Bo L, Xiao C, Hualin C, Mohammad M, Xiangguang T, Luqi T, Yi Y and Tianling R 2016 Surface
Acoustic Wave Devices for Sensor Applications J. Semicond. 37 21001.
[6] Li S, Deng F, Ye Y, Fu G, Liu B, Wang F and Wang H 2015 Optical Waveguide and 1 . 54 μm
Photoluminescence Properties in RF Sputtered Er/Yb-Doped ZnO Thin Films Thin Solid Films 596
51–55.
[7] Nour E, Nur O and Willander M 2017 Zinc Oxide Piezoelectric Nano-generators for Low Frequency
Applications Semicond. Sci. Technol. 32 064005.
[8] Shin J, Shin D, Lee H and Lee J 2011 Properties of Multilayer Gallium and Aluminum Doped ZnO
(GZO / AZO ) Transparent Thin Films Deposited by Pulsed Laser Deposition Process Trans.
Nonferrous Met. Soc. China 21 96–99.
[9] Liu Y, Li Y and Zeng H 2013 ZnO-Based Transparent Conductive Thin Films: Doping,
Performance, and Processing J Nanomater. 2013 196521.
[10] Schmidt-Mende L and MacManus-Driscoll J L 2007 ZnO- nanostructures, defects and devices
Mater. Today 10 40–8.
[11] Kumar R, Al-Dossary O, Kumar G and Umar A 2015 Zinc oxide nanostructures for NO 2 gas–sensor
applications Nano Micro Lett. 7 97–120.
[12] Musat V, Rego A M, Monteiro R and Fortunato E 2008 Microstructure and gas-sensing properties of
sol–gel ZnO thin films Thin Solid Films 516 1512–15.
[13] Zeng W, Liu X, Guo X, Niu Q, Yi J, Xia R and Min Y 2017 Morphology analysis and optimization:
crucial factor determining the performance of perovskite solar cells Molecules 22 520.
[14] Son D, Im J, Kim H and Park N 2014 11% Efficient Perovskite Solar Cell Based on ZnO Nanorods:
an Effective Charge Collection System J. Phys. Chem. C 118 16567–73.
[15] Sun Y, Chen L, Bao Y, Zhang Y, Wang J, Fu M, Wu J and Ye D 2016 The applications of
morphology controlled ZnO in catalysis Catalyst 6 188.
[16] Bender M, Fortunato E, Nunes P, Ferreira I, Marques A, Martins R, Katsarakis N, Cimalla V and
Kiriakidis G 2003 Highly Sensitive ZnO Ozone Detectors at Room Temperature Jpn. J. Appl. Phys.
42 435–437.
[17] Kumar V, Singh R G, Purohit L P and Singh F. 2013 Effect of swift heavy ion on structural and
optical properties of undoped and doped nanocrystalline zinc oxide films Adv. Mat. Lett. 4 423–7.
[18] Balakrishnan L, Gokul Raj S, Meher S R, Asokan K and Alex C Z 2015 Impact of 100 MeV Ag 7+
SHI irradiation fluence and N incorporation on structural , optical , electrical and gas sensing
properties of ZnO thin films Appl. Phys. A 119 1541–53.
[19] Gupta S, Singh F, Lalla N and Das B 2017 Swift Heavy Ion Irradiation Induced Modifications in
Structural , Microstructural , Electrical and Magnetic Properties of Mn Doped SnO 2 Thin Films Nucl.
Instr. Meth. Phys. Res. B 400 37–57.
[20] Decremps F, Pellicer-Porres J, Saitta A M, Chervin J C and Polian A 2002 High-pressure Raman
spectroscopy study of wurtzite ZnO Phy. Rev. B 65 092101.
[21] Min Y S, An C J, Kim S K, Song J and Hwang C S 2010 Growth and characterization of conducting
ZnO thin films by atomic layer deposition Bull. Korean Chem. Soc. 31 2503-8.
[22] Cusco R, Llado E A, Ibanez J, Artus L, Jimenez J, Wang B and Callahan M 2007 Temperature
dependence of Raman scattering in ZnO Phys. Rev. B 75 165202.
[23] Sharma A, Verma K D, Varshney M, Singh A P, Kumar Y, Srivastava S, Vijay Y K, Asokan K,
Choudhary R J and Kumar R 2011 Growth of nanopillars in SnO 2 thin films by ion irradiation and its
gas sensing properties Adv. Sci. Lett. 4 501–7.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
AUTHOR SUBMITTED MANUSCRIPT - MRX2-100290.R1
ce
pte
dM
an
us
cri
pt
[24] Thakurdesai M, Mahadkar A, Kanjilal D and Bhattacharyya V 2008 Nanocrystallisation of TiO2
induced by dense electronic excitation Vacuum 82 639–44.
[25] Kumar P, Kartha C, Vijayakumar K, Singh F, Avasthi D, Abe T, Kashiwaba Y, Okram G, Kumar M
and Kumar S 2005 Modifications of ZnO Thin Films under Dense Electronic Excitation J. Appl.
Phys. 97 13509.
[26] Bakri A, Sahdan M, Adriyanto F, Raship N, Said N, Abdullah S and Rahim M 2017 Effect of
Annealing Temperature of Titanium Dioxide Thin Films on Structural and Electrical Properties AIP
Conf. Proc. 1788 30030.
[27] Szenes G. 2002 Mixing of nuclear and electronic stopping powers in the formation of surface tracks
on mica by fullerene impact Nucl. Instr. Meth. Phys. Res. B 191 27–31.
[28] Szenes G., Horvath Z E, Pecz B, Paszti F and Toth L 2002 Tracks induced by swift heavy ions in
semiconductors Phys. Rev. B 65 045206.
[29] Mohanty T, Satyam P and Kanjilal D 2006 Synthesis of Nanocrystalline Tin Oxide Thin Film by
Swift Heavy Ion Irradiation J. Nanosci. Nanotechnol. 6 1–6.
[30] Audouard A, Balanzatl E, Jousset J C, Lesueurg D and Thomi L 1993 Atomic displacements and
atomic motion induced by electronic excitation in heavy-ion-irradiated amorphous metallic alloys J.
Phys: Condens. Matter 5 995-1018.
[31] Wang J, Qi Y, Zhi Z, Guo J, Li M and Zhang Y 2007 A Self-Assembly Mechanism for Sol – Gel
Derived ZnO Thin Films Smart Mater. Struct. 16 2673–79.
[32] Xu Q et al 2007 Superheating and Supercooling of Ge Nanocrystals Embedded in SiO 2 J. Phys.:
Conf. Ser. 61 1042.
[33] Khranovskyy V and Yakimova R 2012 Morphology engineering of ZnO nanostructures Physica B
Condens. Matter. 407 1533–7.
[34] Bedia A, Bedia F Z, Aillerie M, Maloufi N and Benyoucef B 2015 Morphological and optical
properties of ZnO thin films prepared by spray pyrolysis on glass substrates at various temperatures
for integration in solar cell Energy Procedia 74 529–38.
[35] Sharma S, Periasamy C and Chakrabarti P 2015 Thickness dependent study of RF sputtered ZnO
thin films for optoelectronic device applications Electron. Mater. Lett. 11 1093-101.
Ac
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Page 10 of 10
Документ
Категория
Без категории
Просмотров
2
Размер файла
644 Кб
Теги
2053, 2faa9580, 1591
1/--страниц
Пожаловаться на содержимое документа