Journal of Modern Physics, 2011, 2, 341-349
doi:10.4236/jmp.2011.25042 Published Online May 2011 (http://www.SciRP.org/journal/jmp)
MOCVD of Molybdenum Sulphide Thin Film via Single
Solid Source Precursor Bis-(Morpholinodithioato-s,s’)-Mo
Bolutife Olofinjana1, Gabriel Egharevba2, Bidini Taleatu1, Olum id e Akinwunm i1, Ezekie l Oladele Ajayi1
1Department of Physics, Obafemi Awol ow o University, Ile- Ife, Nigeria
2Department of Chemistry , Obafemi Awolowo University, Ile-Ife, Nigeria
Received January 12, 2011; revised March 16, 20 1 1; acce pted April 7, 2011
Abstract
A single solid source precursor bis-(morpholinodithioato-s,s’)-Mo was prepared and molybdenum sulphide
thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD)
technique at deposition temperature of 420˚C. The film was characterized using Rutherford Backscattering
Spectroscopy (RBS), Ultraviolet-Visible Spectroscopy, Four-point Probe technique, Scanning Electron Mi-
croscopy (SEM), X-ray Diffractometry (XRD) and Atomic Force Microscopy (AFM). A direct optical band
gap of 1.77 eV was obtained from the analysis of the absorption spectrum. The sheet resistance was found to
be of the order of 10–5 Ω–1·cm–1. SEM micrographs of the films showed the layered structure of the film with
an estimated grain size that is less than 2 µm while XRD indicates parallel orientation of the basal plane to
the substrate surface.
Keywords: Molybdenum Sulphide, Precursor, Metal Organic Chemical Vapour Deposition (MOCVD), Thin
Film, Characterization
1. Introduction
Transition metal chalcogenides constitute an important
class of functional materials that are prime candidates for
the exploration of structure-property relationships in sol-
ids. Subtle changes in shape, size and phase of these ma-
terials result in variations in physical properties which
can be exploited for various technological applications.
This wide range of interesting technological applications
has been the primary driving force behind much of the
interest in these solid state compounds. Transition metal
dichalcogenides (TMDC) have been widely studied [1-3].
These materials exhibit a wide range of electronic prop-
erties ranging from insulating to conducting with evi-
dence of superconductivity in some of the members of
the class [4].
The unique characteristic of molybdenum disulphide,
MoS2 is its highly anisotrop ic crystal layer structure. It is
characterized by a lamellar structure which is similar to
that of graphite [2]. Monolayers of Mo are sandwiched
between monolayers of sulphur which are held together
by relatively weak Van der Waals bonding between
S-Mo-S layers. There is a strong covalent bonding within
the sandwiches i.e. between molybdenum and sulphur
atom. Each layer comprises of a layer of Mo atoms ar-
ranged in hexagonal array situated between two hexago-
nal layers of S atoms. Furthermore, the MoS2 layer struc-
ture can exhibit two types of crystalline orientation, ei-
ther the basal planes are parallel or perpendicular to the
substrate. In contrast, MoS3 exist only in an amorphous
form with short range order [5].
Molybdenum sulphide thin films have also found in-
dustrial applications in the field of optical devices and
electronics. These applications arise from their optical
and electrical properties. They have band gaps (1.1 - 1.8
eV) well fitted to solar spectrum [6-8]. The direct and
indirect gaps are derived from non bonding molecular
orbital which leads to high corrosion resistance [9]. As a
result, they are excellent candidates for efficient solar
energy cells [10,11]. The layered structure of molybde-
num sulphide enables weak Van der Waals interaction at
the surface interface substantially relieving the lattice
mismatch problem which leads to generation of disloca-
tion at the interface that acts as minority carrier recom-
bination centers detrimental to cell efficiency. Photo-
voltaic applications of these materials have been sug-
gested and encouraging results were obtained. However,
Jamieson and Jakovidis (2004) [12] proposed that the

B. OLOFINJANA ET AL. 342
MoS2 thin films must be textured for an efficient hetero-
junction photovoltaic cell. Ponomarev et al. (1998) [13]
on the other hand concluded that MoS2 thin films are
photoactive in which photoconductivity measurements
reveal a direct band gap of 1.71 eV with Van der Waals
planes parallel to substrate.
Molybdenum sulphide thin films also have wide range
of potential application as field emitters [14,15], ther-
moelectric materials [16], catalyst [17], in electrochro-
mic devices [18,19], and as cath ode in secondary lithium
batteries [20-22]. The intercalation of lithium into mo-
lybdenum sulphide produces a material that is highly
useful in lithium ion batteries because of its ability to
exchange lithium reversibly in non aqueous electrolytes.
The amount of intercalated lithium and also the reversi-
ble extracted lithium depend on the quality of MoS2 and
their prior treatment [23]. Furthermore, Imanishi et al.
(1992) [20] observed that the discharge and charge char-
acteristics strongly depend on the lithium diffusion in the
Van der Waals gap.
Molybdenum sulphide thin films have been prepared
by variety of techniques. Such techniques include spin
coating [5,24], radio frequency (rf) sputtering [12,25,26],
dc magnetron sputtering [27-31], dip coating [32], pulsed
laser deposition and pulsed laser ab lation [33-35]. Oth ers
include, electrodeposition [6,11,13], successive ionic
layer adsorption and reaction (SILAR) [36], Chemical
reaction technique [37], CVD [38-40] and so on. In the
latter case, Schleich et al. (1989) [40] used molybdenum
hexafluoride (MoF6) and Hexamethyldisulphide (HMDST)
as precursors while Endler et al. (1999) [38] used MoCl5
and H2S as precursors. However, Cheon et al. (1997) [39]
used a metal organic precursor tert-butyl thioate Mo
(S-t-Bu)4 which is an air sensitive compound.
The use of MOCVD technique has received much at-
traction due to its great potential application to fabricate
high quality films. Most of the other techniques have
their different deficiencies ranging from non-uniformity
of films to lack of reproducibility in composition of films
with different levels of impurity. This is due to the fact
that two or more precursor sources of different aerosol
properties are used.
In this work, we report the preparation of bis-(mor-
pholinodithioato-s,s’)-Mo which is a single solid source
precursor and the deposition of molybdenum sulphide
thin films from this precursor through MOCVD method
on sodalime glass substrate at deposition temperature of
420˚C. Compositional study; optical and electrical char-
acterization; surface morphology, structure and rough-
ness of the films are also reported.
2. Experimental
2.1. Precursor Preparation
The single solid source precursor, bis-(morpholinodi-
thioato-s,s’)-Mo was prepared using the procedure re-
ported by Ajayi et al. (1994) [41]. This method has also
been extended to cover ternary and quaternary sulphides
[42,43]. The intermediate complex, ammonium mor-
pholino-dithiocarbamate was prepared according to the
method re po rt ed by Ajayi et al. (1994) [41].
Ammonium morpholino-dithiocarbamate (14.42 g,
0.08 mol) was dissolved in warm methanol (60 cm3) en-
suring that the compound was completely dissolved. A so-
lution of molybdenum(V) chloride, MoCl5 (10.93 g, 0.04
mol) in methanol (60 cm3), was then added dropwise to
the solution of ammonium morpholino-dithiocarbamate
in methanol while stiring vigorously on a hot plate. The
product obtained as a precipitate was filtered off and later
dried in a dessicator to yield 11.78 g (69.70% y ield).
2.2. Thin Film Deposition
The thin film of molybdenum sulphide was prepared by
the pyrolytic method of MOCVD which has been re-
ported previously [44]. The substrate used was sodalime
glass slides with composition O,Si,Na,Ca,Mg,Al =
60,25,10,3,1,1. The film was deposited at temperature of
420˚C. The set up for the depositi on is shown i n Figure 1.
Figure 1. Apparatus for pyrolysis of the precursor.

B. OLOFINJANA ET AL. 343
The fine powder of the precursor, bis-(morpholino-
dithioato-s,s’)-Mo was poured in an unheated receptacle
and Argon gas (dried by passing it through calcium chlo-
ride) was blown through the fine powder precursor at the
rate of 2.5 dm3 per minute. The Argon borne precursor
was transported into the working chamber which was
maintained at 420˚C by an electrically heated furnace.
The substrates were supported on stainless steel blocks to
ensure good and uniform thermal contact. The time of
deposition was two hours. In the hot zone, the precursor
first sublimed before thermal decomposition, resulting in
the formation of the films. This method does not require
a pump to remove the by-products as they are swept out
by the carrier gas. It has the added advantage that heating
of the source material is unnecessary. The whole process
was carried out inside a fume hood.
2.3. Characterization of the Films
Rutherford backscattering spectroscopy (RBS) was used
to determine the elemental composition, stoichiometry
and thickness of the film. The RBS facility is a 7 MV
Tandem accelerator of IBM geometry (scattering con-
figuration where the incident beam, surface normal, and
detected beam are all coplanar) with integrated beam
dose of 10.0 µC. The detector solid angle was 0.833 msr
with a resolution of 12 keV. The incident beam is He+
with energy 2.2 MeV and beam current of 3.8 nA.
The optical absorbance of the thin film was investi-
gated in other to study the optical behavior of the thin
film using Pye-Unicam 400 series Helios Alpha Version
2.05 UV-Visible spectrophotometer. All measurements
were made at room temperature with blank sodalime
glass substrate in the reference beam. Standardization
was done by first replacing the coated substrate with a
plain substrate in the sample position; thus we had plain
against plain subst rate .
The electrical characterization of the film was per-
formed using the four point probe technique. The four
point collinear probe configuration was employed with
silver paste at each of the points for ohmic contact. Cur-
rent-voltage measurement was done using Keithley 2400
Source meter with Rolls and Keener probes. The two
outer probes were used to source current while the two
inner probes sense the resulting voltage drop across the
sample. The distance of separation between each of the
probe was 1 cm. A hand lens was used to monitor the
probe from puncturing the film.
The surface morphology and surface roughness of the
films were obtained using Zeiss Supra 40 with GEMINI
column Scanning Electron Microscope and PSIA-XE
100 Atomic Force Microscopy machine. The electron
beam of the SEM was 0.1 keV - 30 keV with nominal
resolution of 1 nm at 10 keV. To achieve atomic scale
resolution, a sharp stylus (radius ̴ 1 - 2 nm) attached to the
cantilever was used in the AFM to scan point by point and
contouring it while a constant small force is applied to the
stylus. X-Ray Diffraction (XRD) of the film was per-
formed with MD-10 model X-ray mini diffractometer
using Cu-Kα radiation (λ = 0.15418 nm). Chemical phase
identification was performed using a computer based
system with the standard powder diffraction file (PDF)
embedded in the diffractomoter. A data base from the
International Center for Diffraction Data was also used
in comparing the XRD pattern of the films.
3. Results and Discussion
The compositional analysis of the film was carried out
using Rutherford Backscattering Spectroscopy (RBS).
RBS was also used to determin e the thickness o f the film.
The RBS spectrum of the film is shown in Figure 2. The
stoichiometric ratio of the film was found to be Mo:S =
0.33:0.67 while the thickness was estimated to be 70 nm.
The mismatch in the RBS spectrum is as a result of
charging effect from the substrate. This shows that the
decomposition of bis-(morpholinodithioato-s,s’)-Mo in
inert gas medium (Argon) produced molybdenum sul-
phide thin film.
Optical characterization constitutes the most direct and
perhaps the simplest approach for probing the band
structure of the deposited film. The UV-Visible spectrum
of the thin film is shown in Figure 3. The spectrum is a
plot of absorbance against incident photon wavelength at
normal incidence and at room temperature. The UV-
Visible spectrum shows that the optical absorbance of
the film increases with increasing energy of the photon
0100 200 300 400 500
Channel
0
5
10
15
20
25
30
Normalized Yield
0.0 0.5 1.0 1.5 2.0
Energy (MeV)
Figure 2. RBS spectrum of the thin film. (The black line
represents the experimental spectrum while the red line
represents the simulated spectrum.)

B. OLOFINJANA ET AL. 344
Figure 3. Absorbance versus wavelength for the thin film.
indicating that the film is highly absorbing in the visible
region. Ponomarev et al. (1998) [13] attributed such
strong absorption to the absorption of some impurities
from the substrate or the presence of MoO3-x. It could
also be true in this case, since it is possible for some of
the elements of the sodalime glass substrate to diffuse to
the surface during the deposition process [45]. The strong
absorption can also indicate high amount of defect. Light
scattering from the micrometer sized grains of the film
can also be the reason for the strong absorption in the
visible region.
From both the absorbance and film thickness obtained
from RBS, the absorption coefficient α was calculated
from the expression
11
ln
x
T




(1)
where, x is the thickness of the film, T = 10–a is the
transmittance and a = absorbance. The dependence of
absorption coefficient on photon energy can be obtained
for optical transition processes using the time-dependent
perturbation theo ry. Th e optical ab so rp tio n at high valu es
of absorption coefficient (α ≥ 104) above the exponential
tail follows a power law of the general form

n
g
Ahv E  

(2)
where h = Planck’s constant, ν = frequency, Eg = energy
gap and A = constant of proportionality. The expon ent, n,
which characterize the transition process can take values
2, 3, 1/2, or 3/2 for indirect allowed, indirect forbidden,
direct allowed and direct forbidden transitions respec-
tively. From equation 1 square of the absorption coeffi-
cient, α2 was calculated. Figure 4 shows the plot of α2
against the energy of the photon for the thin film. The
extrapolation of the straight region of the graph to the
energy axis gives the direct band gap energy for the thin
film. The estimated value of the band gap is 1.77 eV.
Figure 4. Absorption coefficient square α2 versus energy for
the thin film.
This falls between the values of the band gaps reported
for molybdenum sulphide thin films [6,10-13]. From the
band structure of molybdenum sulphide, the energy
gap is always between the filled dz2 band and the
higher lying conduction bands [46]. The dz2 band
may be half filled or completely filled. The transition
then becomes easy which may correspond to the
semiconducting behavior of the material. On the con-
trary, Schmidt et al. (1995) [47] reported a value of
1.05 eV which is a bit low. This was attributed to the
presence of band tails characteristics of the amor-
phous state. In this case, a value of 1.77 eV may then
suggest the crystalline state of the film.
Electrical characterization of the film was done using
the four point probe method. The sheet resistance Rs of
the film was obtained using the expression [48],
π
ln 2
SV
R
I



(3)
From the sheet resistance and the thickness from RBS,
resistivity, ρ and conductivity, σ of the films were also
calculated from the following equations,
π
ln 2
S
x
V
Rx
I


 

(4)
1



(5)
The sheet resistance of film was estimated to be 2.25 ×
105 Ω/sq. The value obtained in this work is of the same
order of magnitude with those reported in the literature.
Ponomarev et al. (1998) [13] reported an approximate
value of 7.1 × 105 Ω/sq while Schleich et al. (1989) [40]
reported a value of 0.9 × 105 Ω/sq for MoS3 thin films.
From equations 3 and 4 with the value of the thickness
obtained from RBS, the conductivity of the film was
calculated to be 0.86 Ω–1·cm–1. This is in agreement with
values reported in the literature (10–3 Ω–1·cm–1 to 101

B. OLOFINJANA ET AL. 345
Ω–1·cm–1). Cheon et al. (1997) [39] also reported th at the
conductivity of amorphous MoS2 films deposited at 200˚C
by CVD method is very near 1.0 Ω–1·cm–1. Levasseur et
al. (1995) [46] and Schmidt et al. (1995) [47] have sepa-
rately shown that molybdenum sulphide thin films with
low oxygen content have high conductivity value (10–1
Ω–1·cm–1) with semiconducting behavior when compared
with films with high oxygen content (10–5 Ω–1·cm–1). This
is an indication that our film contains little or no oxygen.
Figures 5(a) and 5(b) show the SEM micrographs of
(a)
(b)
Figure 5. Scanning electron micrograph of the thin film. ((a). Magnification: 39.80 kx; (b). Magnification: 63.99 kx.)

B. OLOFINJANA ET AL. 346
the films at various magnifications. These clearly show
the layered structure associated with molybdenum sul-
phide thin films. The micrographs were analyzed using
IMAGEJ software to obtain the grain size. The average
grain size was estimated to be below 2 µm. The films ap-
pear to be dense, homogeneous and of compact struc-
ture with closely packed grains. Upon closer inspection
at high magnification, it is apparent that the films are
pin-hole free and continuous with uniformly distributed
grains which covered the substrate very well.
Atomic Force Microscopy was done in the non contact
mode. The surface roughness of the films over a cross
sectional area of 10 µm2 is as shown (in 2-D) in Figure 6.
Root mean square surface roughness values for the film
is less than 50 nm, indicating that the films are relatively
smooth. The root mean square was obtained at a scan
rate of 0.7 Hz. The relatively low root mean square
roughness value coupled with dimension of the grain
indicates the effectiveness of this technique in particle
size distribution and production of films of high quality
that is relatively smooth.
The XRD diffraction pattern of the film is shown in
Figure 7. Intense peaks occur at diffraction angles, 2θ =
11.37o, 14.39o, 29.03o, 32.68o, 33.51o. This confirms the
crystalline nature of the film. The diffraction pattern in-
dicates MoS2 structure (Card Number 37-1492). The
peak at 2θ = 14.39o corresponds to (002) plane, 29.03o to
(004) plane, 32.68o to (100) plane and 33.51o to (101).
The peaks corresponding to (002) and (004) indicates
parallel orientation of the basal (Van der Waals) plane to
the substrate surface while those that correspond to (100)
and (101) indicate perpendicular orientation of the basal
plane. However the intensities of the peaks correspond-
ing to the (00l) (l = 2, 4) planes are higher than that of
the (100) and (101) planes. This indicates the formation
of highly textured film with the Van der Waals planes
oriented parallel to the surface of the substrate. This
property is of particular importance for photovoltaic and
tribological applications [11,13]. The peak at 2θ = 11o
can be attributed to a local (002) interplanar expansion of
the crystal structure normal to MoS2 planes [49]. The
peaks at 2θ = 24.95o and 27.00o can be attributed to the
substrate which may be due to the small thick ness of the
film. The lattice constant c found from the XRD data was
Figure 6. Atomic force microscopy images of the thin film.
Figure 7. XRD spectrum of the thin film.

B. OLOFINJANA ET AL.347
found to be 12.31 Å. This value is approximately the
same value (12.298 Å) reported in the literature (File
Number 37-149 2). The good agreement of the value of c
with the standard is an indication that our film contains
little or no impurities. Even if there are impurities, the
impurities did not dissolve in the film but may concen-
trate at the grain boundaries.
4. Conclusion
On the basis of the above experimental results, bis-
(morpholinodithioato-s,s’)-Mo was prepared as a single
solid source precursor from commercial reagents. This
has not been hitherto used as a precursor in any MOCVD
technique employed in the preparation of molybdenum
sulphide thin film. Thermal decomposition of bis-(mor-
pholinodithioato-s,s’)-Mo yields molybdenum sulphide
thin film in which compositional study with RBS gave
the stoichiometric ratio of the film to be Mo:S = 0.33:
0.67 while the thickn ess was estimated to be 70 nm. It is
believed that the deposition of molybdenum sulphide
thin film from single solid precursor using MOCVD tech-
nique provides another method of depositing molybde-
num sulphide thin film, with the advantage of large area
deposition. A simple and cost effective method that is
well suitable for large scale production of molybdenum
sulphide thin film is established.
Optical absorption measurement indicates a material
that is highly absorbing in the visible part of the spectrum
with a direct optical energy band gap of 1.77 eV. Elec-
trical characterization of the film using the four point pro-
be method gave the value of sheet resistance and conduc-
tivity to be 2.25 × 105 Ω/sq and 0.86 Ω–1·cm–1 respectively.
The morphology of the film shows the layered struc-
ture associated with molybdenum sulphide thin films
while the average grain size is less than 2 µm. XRD
shows the crystalline nature of the film indicating paral-
lel orientation of the basal (Van der Waals) plane to the
substrate with lattice constant c estimate d to be 12.3 1 Å .
5. Reference
[1] M. Regular, C. Ballif, J. H. Moser and F. Lévy, “Struc-
tural, Chemical and Electrical Characterization of Reac-
tively Sputtered WSx Thin Films,” Thin Solid Films, Vol.
280, No. 1-2, 1996, pp. 67-75.
doi:10.1016/0040-6090(95)08206-9
[2] P. D. Fleischauer, “Fundamental Aspect of the Electronic
Structure Materials Properties and Lubrication Perform-
ance of Sputtered MoS2 Films,” Thin Solid Films, Vol.
154, No. 1-2, 1987, pp. 309-322.
doi:10.1016/0040-6090(87)90375-0
[3] R. A. Wold, “Electronic Structure of MoSe2, MoS2 and
WSe2. I. Band-Structure Calculation and Photoelectron
Spectroscopy,” Physical Review B, Vol. 35, No. 12, 1987,
pp. 6195-6202. doi:10.1103/PhysRevB.35.6195
[4] H. Lee, M. Kanai and C. Kawai, “Preparation of Transi-
tion Metal Chalcogenide Thin Films by Pulsed Laser Ab-
lation,” Thin Solid Films, Vol. 227, No. 1, 1996, pp.
98-100. doi:10.1016/0040-6090(95)08022-8
[5] J. Pütz and M. A. Aegeter, “Spin Deposition of MoSx
Thin Films,” Thin Solid Films, Vol. 351, No. 1-2, 1999,
pp. 119-124. doi:10.1016/S0040-6090(99)00255-2
[6] R. S. Patil, “Electrosynthesis of the Molybdenum Disul-
phide Thin Films and Characterization,” Thin Solid Films,
Vol. 340, No. 1-2, 1999, pp. 11-12.
doi:10.1016/S0040-6090(98)01375-3
[7] V. Thanigaimani and M. A. Angadi, “Thickness De-
pendence of Temperature Coefficient of Resistance and
Neel Temperature in MnTe Films,” Journal of Materials
Science Letters, Vol. 12, No. 13, 1993, pp. 1052-1056.
doi:10.1007/BF00420217
[8] P. Pramanik and S. Bhattacharya, “Chemical Synthesis of
Nanosized Oxides,” Material Research Bulletin, Vol. 25,
No. 1, 1990, pp. 15-23.
doi:10.1016/0025-5408(90)90157-W
[9] A. Arucharry, “Photoelectrochemistry and Photovoltaics
of Layered Semiconductors,” Kluwer Academic Pub-
lisher, Dordrecht, 1992.
[10] P. K. Nair, J. Campos and M. T. S. Nair, “Optoelectron-
ics Characteristics of Chemically Deposited Cadmium
Sulphide Thin Films,” Semiconductor Science Technol-
ogy, Vol. 3, No. 2, 1988, pp. 134-145.
doi:10.1088/0268-1242/3/2/010
[11] E. A. Ponomarev, M. Neumann-Spallart, G. Hodes and C.
Lévy-Clement, “Electrochemical Deposition of MoS2
Thin Films by Reduction of Tetrathiomolybdate,” Thin
Solid Films, Vol. 280, No. 1-2, 1996, pp. 86-89.
doi:10.1016/0040-6090(95)08204-2
[12] I. Jamieson and G. Jakovidis, “Thin Film Texture of Lay-
ered Molybdenum Disulphide for Photovoltaic Cells,”
Optoelectronic and Microelectronic Materials and De-
vices, Vol. 8, No. 8, 2004, pp. 117-120.
doi:10.1109/COMMAD.2004.1577506
[13] E. A. Ponomarev, R. Tenne, A. Katty and C. Lévy-Clem-
ent, “High Oriented Photoactive Polycrystalline MoS2
Layers Obtained by Van der Waals Rheotaxy Technique
from Elecroc hemically Deposited T hin Films,” Solar En-
ergy Materials and Solar Cells, Vol. 52, No. 1, 1998, pp.
125-133. doi:10.1016/S0927-0248(97)00277-8
[14] Y. B. Li, Y. Bando, D. Goldberg and K. Kurashima,
“Field Emission from MoO3 Nanobelts,” Applied Physics
Letter, Vol. 81, No. 26, 2002, pp. 5048-5050.
doi:10.1063/1.1532104
[15] Y. B. Li, Y. Bando and D. Goldberg, “MoS2 Nanoflowers
and Their Field-Emission Properties,” Applied Physics
Letters, Vol. 82, No. 12, 2003, pp. 1962-1964.
doi:10.1063/1.1563307
[16] T. Caillat, J. P. Fleurial and G. J. Synder, “Potential of
Chevrel Phases to Thermoelectric Applications,” Solid
State Sciences, Vol. 1, No. 7-8, 1999, pp. 535-544.

B. OLOFINJANA ET AL. 348
[17] C. Song, “An Overview of New Desulfurization for Ul-
tra-Clean Gasoline, Diesel Fuel and Jet Fuel,” Catalyst
Today, Vol. 86, No. 1-4, 2003, pp. 211-263.
doi:10.1016/S0920-5861(03)00412-7
[18] P. R. Somani and S. Radhakrishnan, “Electrochromic
Materials and Devices: Present and Future,” Materials
Chemistry and Physics, Vol. 77, No. 1, 2003, pp. 117-133.
doi:10.1016/S0254-0584(01)00575-2
[19] P. M. Monk, T. Ali and R. D. Patridge, “The Effect of
Doping Electrochromic Molybdenum Oxide with Other
Metal Oxide,” Solid State Ionics, Vol. 80, No. 1-2, 1995,
pp. 75-85. doi:10.1016/0167-2738(95)00130-X
[20] N. Imanishi, K. Kanamura and Z. Takahara, “Synthesis of
MoS2 Thin Film by Vapour Deposition Method and
Characteristics as a Cathode of the Lithium Secondary
Battery,” Journal of Electrochemical Society, Vol. 139,
No. 8, 1998, pp. 2082-2087. doi:10.1149/1.2221182
[21] G. Meunier, R. Dormoy, and A. Levasseur, “New Posi-
tive-Electrode Materials for Lithium Thin Film Secon-
dary Batteries,” Material Science and Engineering B, Vol.
3, No. 1-2, 1989, pp. 19-23.
doi:10.1016/0921-5107(89)90173-6
[22] S. D. Jones and J. R. Akridges, “Development and Per-
formance of a Rechargeable Thin Film Solid State Mi-
crobattery,” Journal Power Sources, Vol. 54, 1994, pp.
63-67.
[23] R. Dominko, M. Gaberscek, D. Arcon, A. Mrzel, M.
Remslar, D. Mihailovic, S. Pejovnik and J. Jamik, “Elec-
trochemical Preparation and Characterization of LizMoS2-x
Nanomaterials,” Electrochimica Acta, Vol. 48, No. 20-22,
2003, pp. 3079-3084.
doi:10.1016/S0013-4686(03)00384-0
[24] J. Pütz and M. A. Aegeter, “MoSx Thin Films by Ther-
molysis of a Single Source Precursor,” Journal of Sol-Gel
Science and Technology, Vol. 19, No. 1-3, 2000, pp.
821-824.
[25] J. Moser, J. H. Liao and F. Levy, “Texture Characteriza-
tion of Sputtered MoS2 Thin Films by Cross Section
TEM Analysis,” Journal of Physics D: Applied Physics,
Vol. 23, No. 5, 1990, pp. 624-626.
doi:10.1088/0022-3727/23/5/026
[26] J. K. G. Panitz, L. E. Pope, J. E. Lyons and D. J. Staley,
“The Tribological Properties of MoS2 Coatings in Vac-
uum Low Relative Humi dity and High Re lative Humidity
Environments,” Journal of Vacuum Science & Technol-
ogy A, Vol. 6, No. 3, 1988, pp. 1166-1170.
doi:10.1116/1.575669
[27] S. Mikhailov, A. Savan, E. Pflüger, L. Knoblauch, R.
Hauert, M. Simmonds and H. Van Swygehoven, “Mor-
phology and Tribological Properties of Metal (Ox-
ide)-MoS2 Nanostructural Multilayer,” Surface and Coat-
ing Technology, Vol. 105, No. 1, 1998, pp. 175-183.
doi:10.1016/S0257-8972(98)00483-6
[28] N. M. Renevier, V. C. Fox, D. G. Teer and J. Hamsphire,
“Coating Characteristics and Tribological Properties of
Sputtered Deposited MoS2/Metal Composite Coatings
Deposited by Closed Field Unbalanced Magnetron Sput-
ter Ion Plating,” Surface and Coatings Technology, Vol.
127, No. 1, 2000, pp. 24-37.
[29] I. Efeoglu, “Deposition and Characterization of a Multi-
layered-Composite Solid Lubricant Coating,” Reviews on
Advanced Materials Science, Vol. 15, 2007, pp. 87-94.
[30] S. P. Kaye, J. S. Kheyrandish, J. S. Colligon and E. W.
Roberts, “Ion Beam Modification of the Physical Proper-
ties of MoSx Films,” Thin Solid Films, Vol. 228, No. 1-2,
1993, pp. 252-256. doi:10.1016/0040-6090(93)90610-2
[31] D. Y. Wang, C. L. Chang, Z. Y. Chen and W. Y. Ho,
“Microstructure and Tribological Characterization of
MoS2-Ti Composite Solid Lubricating Films,” Surface
and Coatings Technology, Vol. 120-121, 1999, pp.
629-635. doi:10.1016/S0257-8972(99)00431-4
[32] S. C. Ray, “Structure and Optical Properties of Molyb-
denum Disulphide (MoS2) Thin Film Deposited by the
Dip Technique,” Journal of Material Science Letters, Vol.
19, No. 9, 2000, pp. 803-804.
doi:10.1023/A:1006737326527
[33] H. Lee, M. Kanai and C. Kawai, “Preparation of Transi-
tion Metal Chalcogenide Thin Films by Pulsed Laser Ab-
lation,” Thin Solid Films, Vol. 277, No. 1, 1996, pp.
98-100. doi:10.1016/0040-6090(95)08022-8
[34] J. J. Hu, J. E. Bultman and J. S. Zabinski, “Microstruct ure
and Lubrication Mechanism of Multilayered MoS2/Sb2O3
Thin Films,” Tribology Letters, Vol. 21, No. 2, 2006, pp.
169-174. doi:10.1007/s11249-006-9035-6
[35] J. J. Hu, J. S. Zabinski, J. E. Bultman, J. H. Sanders and
A. A. Voevodin, “Structural Characterization of Pulsed
Laser Deposited Mo-Sx-WSey Composite Films of Tri-
bological Interests,” Tribology Letters, Vol. 24, No. 2,
2006, pp. 127-135. doi:10.1007/s11249-006-9063-2
[36] H. M. Pathan and C. D. Lokhande, “Deposition of Metal
Chalcogenide Thin Films by Successive Ionic Layer Ad-
sorption and Reaction (SILAR) Method,” Bulletin of Ma-
terial Science, Vol. 27, No. 2, 2004, pp. 85-111.
doi:10.1007/BF02708491
[37] W. Hai-Dou, X. Bin-Shi, L. Jia-Jun and Z. Da-Ming,
“Characterization and Anti-Friction on the Solid Lubrica-
tion of MoS2 Films Prepared by Chemical Reaction
Technique,” Science and Technology of Advanced Mate-
rials, Vol. 6, No. 5, 2005, pp. 535-539.
doi:10.1016/j.stam.2005.03.012
[38] I. Endler, A. Leonhardt, U. Kong, H. Van der Berg, W.
Pitschke and V. Sottke, “Chemical Vapour Deposition of
MoS2 Coatings Using the Precursor MoCl5 and H2S,”
Surface and Coatings Technology, Vol. 120-121, 1999,
pp. 482-488. doi:10.1016/S0257-8972(99)00413-2
[39] J. Cheon, J. E. Gozum and G.S. Girolami, “Chemical
Vapour Deposition of MoS2 and TiS2 Films from the
Metal-Organic Precursors Mo(S-t-Bu)4 and Ti(S-t-Bu)4,”
Chemical Materials, Vol. 9, No. 8, 1997, pp. 1847-1853.
doi:10.1021/cm970138p
[40] D. M. Schleich, H. S. Chang, Y. L. Barberio and K. L.
Hanson, “MoS3 Thin Film Cathodes Prepared by Chemi-
cal Vapour Deposition,” Journal of Electrochemical So-
ciety, Vol. 136, No. 11, 1989, pp. 3274-3278.
doi:10.1149/1.2096437

B. OLOFINJANA ET AL. 349
[41] O. B. Ajayi, O. K. Osuntola, I. A. O. Ojo and C. Jeynes,
“Preparation and Characterization of MOCVD Thin
Films of Cadmium Sulphide,” Thin Solid Films, Vol. 248,
No. 1, 1994, pp. 57-63.
doi:10.1016/0040-6090(94)90211-9
[42] A. V. Adedeji, M. A. Eleruja, I. A. O. Ojo, A. Djebah, A.
O. Osasona, J. O. Olowolafe, J. B. Aladekomo and E. O.
B. Ajayi, “Preparation and Optical Characterization of
MOCVD ZnCdInS Thin Films,” Optical Materials, Vol.
14, No. 4, 2000, pp. 345-349.
doi:10.1016/S0925-3467(99)00118-4
[43] M. A. Eleruja, A. V. Adedeji, I. A. O. Ojo, A. Djebah, O.
Osasona, J. B. Aladekomo and E. O. B. Ajayi, “Optical
Characterization of Pyrolytically Deposited ZnxCd1-xS
Thin Films,” Optical Materials, Vol. 10, No. 4, 1998, pp.
257-263. doi:10.1016/S0925-3467(97)00178-X
[44] O. B. Ajayi, “Electrical and Optical Properties of Pyro-
lytically Deposited Indium Oxide,” M.Sc. Thesis, Uni-
versity of Illinois, Urbana, USA, 1970.
[45] B. Olofinjana, G. O. Egharevba, M. A. Eleruja, C. Jeynes,
A. V. Adedeji, O. O. Akinwunmi, B. A. Taleatu, C. U.
Mordi and E. O. B. Ajayi, “Synthesis and Some Proper-
ties of Metal Organic Chemical Vapour Deposited Mo-
lybdenum Oxysulphide Thin Films,” Journal of Material
Science Technology, Vol. 26, No. 6, 2010, pp. 552-557.
doi:10.1016/S1005-0302(10)60084-9
[46] A. Levasseur, E. Schmidt, G. Meunier, D. Gonbeau, L.
Benoist and G. Pfister-Guillouzo, “New Amorphous Mo-
lybdenum Oxysulphide Thin Films: Their Characteriza-
tion and Their Electrochemical Properties,” Journal of
Power Sources, Vol. 54, No. 2, 1995, pp. 352-355.
doi:10.1016/0378-7753(94)02100-H
[47] E. Schmidt, C. Sourisseau, G. Meunier and A. Levasseur,
“Amorphous Molybdenum Oxysulphide Thin Films and
their Physical Characterization,” Thin Solid Films, Vol.
260, No. 1, 1995, pp. 21-25.
doi:10.1016/0040-6090(94)06463-6
[48] D. K. Schroder, “Semiconductor Material and Device
Characterizations,” Willey-Interscience Publication, Ari-
zona, 1998.
[49] D. N. Dunn, L. E. Seitzman and I. L. Signer, “The Origin
of an Anomalous, Low 2θ Peak in X-ray Diffraction
Spectra of MoS2 Films Grown by Ion Beam Assisted
Deposition,” Journal of Materials Research, Vol. 12, No.
5, 1997, pp. 1191-1194. doi:10.1557/JMR.1997.0167