IJPRD, 2014; Vol 6(12):January-2015(05 - 07)
International Standard Serial Number 0974 – 9446
-------------------------------------------------------------------------------------------------------------------------------------------------STRUCTURAL AND MORPHOLOGICAL PROPERTIES 0F INDIUM SELENIDE THIN FILMS DEPOSITED BY
CHEMICAL BATH DEPOSITION
Sanjay B. Bansode *1 and Vasant G. Wagh2
1*
Advanced Physics Laboratory, Department of Physics, University of Pune, Pune- 411 007
2
K.V.N.Naik College of Arts Science and Commerce, Nashik, MH, India
*College affiliated to Savitribai Phule Pune University. Pune.(Maharashtra)
ABSTRACT
Indium selenide films were deposited using chemical bath
deposition. The films were deposited on FTO coated glass
substrate by using In2(SO4)3 as indium source and selenium
powder as selenium source. The films were characterized using
the different techniques with respect to their crystal structure,
optical and electrical properties by means of X-ray diffraction,
scanning electron microscopy. X-ray diffraction studies revealed
that amorphous nature of the deposited films. The scanning
electron microscopy picture of as deposited indium selenide film
layer shows leaf like structure over the surface of the substrate.
Optical absorption study shows that InSe is a direct band gap
material with band gap 1.54 eV.
Correspondence Author
Sanjay B. Bansode,
Advanced Physics Laboratory,
Department of Physics,
University of Pune, Pune- 411 007
Keywords- Indium selenide; Chemical bath deposition; thin films
etc.
INTRODUCTION
Indium selenide is important material for
optoelectronic and photovoltaic application due to
its stability and wider band gap. It can be used as
effective nontoxic substitute for cadmium sulfide
CdS in Cu(InGa)Se2 based on solar cell. Indium
selenide belongs to group III-VI compound
material. Indium selenide could be prepared using
different method such as chemical vapor
deposition [1], Spry pyrolysis[2] chemical bath
deposition[3],evaporation technique[4]. Of this,
chemical bath deposition is simple method which
can be used for deposition of large area thin films.
In present work indium selenide thin films were
deposited by chemical bath deposition, using
triethanolamine [TEA] and Hydrazine hydrate (HH)
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International Journal of Pharmaceutical Research & Development
complexed with indium sulphate. The aim of this
work is to study the structural, optical, surface
morphological properties of indium selenide thin
films using X-ray diffraction, scanning electron
microscopy
(SEM),
electron
dispersive
Spectroscopy, optical absorption.
EXPERIMENTAL DETAILS
Indium selenide films were deposited by
chemical bath deposition. The deposition was
carried out on FTO coated glass substrate by
sequential addition of indium sulphate, 80 %
Hydrazine hydrate, triethanolamine, these solution
used as received. Deposition of InSe was carried
out in alkaline bath. The solution prepared in 30 ml
beaker by sequential addition of 5ml of 0.1M
indium sulphate, 0.1 ml of 0.15M triethanolamine.
Solution was stirred well, under the continuous
stirring condition 0.1 ml of hydrazine hydrate was
mixed and 5 ml of 0.1M Na2se(so3) solution was
added to the bath. The initial pH of the solution
was about 9. Clean and FTO coated glass substrate
were placed vertically in reactive solution at room
temperature. Films were deposited about 72 hours.
The resulting indium selenide films were brownish
in color and very well adherent. Microstructures of
the films were studied using scanning electron
microscope (SEM) for the different magnifications.
The optical absorption measurements in the range
of 350 - 900 nm were carried, XRD patterns were
obtained by using X-ray diffractometer (XRD Rigaku
D/max-2400 with Cu-kα= 0.154nm).
RESULT AND DISCUSSION
The structural identification of indium selenide
thin films was studied with X-ray diffraction
techniques. The XRD was carried out in the range
of diffraction angle of 2θ between 20 and 80. From
X-Ray pattern (Not shown Fig.), It is clear that
indium selenide films are amorphous in nature.
ISSN: 0974 – 9446
However T Fujiwara et al [5] reported that the
growth of In2Se3 phase may be attributed to
amorphous and polycrystalline nature of substrate.
The composition of as deposited films was
determined from energy dispersive X-ray analysis.
SEM image of InSe deposited on FTO coated glass
substrates are shown in Figure 1. The surface
shows random distribution leaf like dense
structure. Film covers the entire substrate surface
which accounts for the high mechanical stability of
deposited films. The atoms deposited on glass
substrate cannot move freely due to insufficient
thermal energy provided to the substrate at room
temperature (fig b), therefore films deposited at
low temperature exhibited poor crystallinity.
(a)
(b)
(c)
FIGURE 1. SEM images of InSe thin film deposited
at on to FTO coated glass substrate at (a) 3000X
and (b) 10000X and (c) 30000X
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International Journal of Pharmaceutical Research & Development
It has been reported that optical band gap
of indium selenide varied from 1.2 to 2.0 eV with
several phases [6]. To determine the optical band
gap of as deposited indium sulfide thin film Figure
2 shows the plot of (αhυ)2 versus (hυ) for the
deposited thin film. The band gap of 1.54 eV was
estimated by extra plotting the straight line part of
the plot to energy axis
ISSN: 0974 – 9446
CONCLUSION
In this paper, structural, and morphological
properties of chemically deposited InSe thin films
were reported. XRD studies showed the
amorphous nature of InSe thin films. SEM shows
random distribution of leaf like structure with
irregular shape. From optical studies gap was found
to be 1.54 eV. Angle of contact confirms high
surface energy of deposited thin film.
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0 .8
REFERENCES
1. J.W. Cheon, J. Arnold, K.M. Yu, E.D. Bourret,
Chem. Matter. 7 (1995), 2273.
2. H.BouZouita, N. Bougulia, S. Dachemin, S.
Fiechetr, A.Dhouib, Renew. Energy 25,
(2002), 131.
3. K. Bindu, M. Lakshmi, S. Bini, C. Sudha Kartha,
K.P. VijYakumar, T.Abe, Y. Kashiwada, in;
proceding of the national symposium on
science and tech. of vaccum and Thin films
(IVSVS-2001), 33 PP.
4. C.H. de Groot, J. S. Moodera, J. Appl. Phys. 89
(2001) 4336
5. T. Fujieara, Y. lgasaki, Journal of Crystal
growth. 178 (1997) 332-334
6. C. Gullien, A Chery, D. Saipkas, phys. Stat. Sol.
(a) 118 (1990) 553
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(absorbance)
2
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0 .0
1 .0
1 .5
2 .0
2 .5
3 .0
E n e rg y (e V )
Figure.2 plot of (absorbance) 2 against Energy (hυ)
for as deposited InSe thin film
Angle of contact
Angle of contact of as deposited films were
measured by using travelling microscope. Angle of
contact is lees than 90o which indicate high surface
energy shown in Figure 3. It shows that resistivity
decreases with increase in temperature this
confirm semiconducting nature.
Figure.3 angle of contact
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