International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 4, April 2015
ISSN 2319 - 4847
Nanostructural Properties of Zirconium oxide
Thin Films prepared by Magnetron Sputtering
Prof. Dr.Abdulhussein K.Elttayef1, Prof.Dr.Ahmed K. Abbas2 , Ghafran .H. Neema2
1
Ministry of Science and Technology
2
University of Wasit, College of Science
ABSTRACT
Nanostructure zirconium films are deposited on glass substrate with different thicknesses 85 and 100 nm by R.F.magnetron
sputtering. X-ray diffraction (XRD) patterns reveal the formation of polycrystalline ZrO2 films after annealing with average
particle size in the range of 13.17 nm and 37.29 nm for thicknesses 85 and 100 nm respectively. The average surface roughness
(Ra) measured with atomic force microscopy (AFM) was ranged between 0.425nm and 0.512 nm.
Keywords: ZrO2: Thin Film; Nanostructure; Optical; Sputtering RF.
1. INTRODUCTION
The oxide thin films are attracting an increasing inter-est because of their potential use as the material with high
dielectric characteristics for manufacturing of the film ca- pacitors and as a buffer layer with high chemical stability at
creation of multi-layers . Recently, oxide ma- terials with high dielectric parameters have been suggested as an
alternative to the currently used SiO2 gate dielectric for complementary application of metal oxide for using in
semiconductor technology. Several oxide materials with high dielectric constant have been investigated as an alternative gate dielectric. However, their application is limited due to the interfacial reaction between dielectric materials
and tradition microelectronic substrates, such as Si sub- strates, during the post annealing processes are known va rious
technologies, which can be used for fabrication of ZrO2 films.
ZrO2 films have been utilized for a wide range of applications like wear resistant coatings, protective coating for optical
mirrors and filters, thermal-barrier coatings, resistive oxygen gas sensor. [1] and high temperature fuel cells and
oxygen detectors. [2-6]. In addition, ZrO2 thin films have been considered to replace SiO2 due to their high k dielectric
property in the metal-oxide-semiconductor transistor [7]. These applications have led to various techniques to
synthesize zirconium oxide thin films including direct current reactive magnetron sputtering[8,9] chemical vapor
deposition[10,11] sol-gel techniques[12] pulsed ion beam evaporation,[13] liquid phase deposition[14] and filtered
cathodic vacuum arc[15] .Radio frequency (RF) reactive magnetron sputtering is a widely used technique which is
affected by several deposition conditions, such as the RF power, mixing ratio of plasma gas, and substrate temperature
[16-17].
In the present work, we report the synthesis of zirconium oxide thin films by RF magnetron sputtering and Study the
structural Properties of ZrO2 Thin Films .Structural analysis of the zirconium oxide thin films was performed by
atomic force microscopy (AFM) and X-ray diffraction (XRD) techniques.
2. EXPERIMENTAL DETAILS
ZrO2 thin films were prepared by RF magnetron sputtering system with a zirconium oxide target of 99.99% purity on
glass substrates. The target was pre-sputtered in an argon atmosphere in order to remove oxide layer. The argon gas
was introduced into the chamber through a flow controller with fine adjustments the sputtering was performed under
Ar (99.999%) atmosphere supplied as working gas through mass-flow controller. The sputtering chamber was
evacuated down to 5 × 10-5 mbar by the turbo molecular pump. Microscope glass slides were used as the substrates for
thin films. Prior to deposition, the glass substrates were cleaned by chromic acid followed by distilled water rinse.
For morphological investigations, AFM images were recorded using Nano scope IIIa scanning probe microscope
controller in a tapping mode.
3. Results and discussion
3.1 Structural Properties
X-ray diffraction (XRD) results suggested that the deposited ZrO2 films were polycrystalline formed by nanoparticles
with average particle size in the range of 13.17 nmand 37.29 nm for thicknesses 85, and 100 nm respectively as shown
in figures (1) and (2) before and after annealing respectively .
The surface morphology of all the ZrO2 films is offered by AFM images in tapping mode shown in figure ( 3 ). All the
ZrO2 films presentation a smooth surface with uniform grains.
Volume 4, Issue 4, April 2015
Page 40
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 4, April 2015
ISSN 2319 - 4847
In this figure the surface morphology discovers the nano-crystalline ZrO2 grains, which rise to make intensive films
significantly with the increased thickness. From the images, it was observed that the surfaces of the films exhibited a
confirmed degree of coarseness and the film came rougher when the thickness increases.
Fig. (1) XRD of ZrO2 thin film of thickness 85nm and 100nm before annealing
Fig. (2) XRD of ZrO2 thin film of thickness 85nm and 100nm after annealing
Volume 4, Issue 4, April 2015
Page 41
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 4, April 2015
ISSN 2319 - 4847
3.2Morphology
The surface morphology of all the ZrO2 films is offered by AFM images in tapping mode shown in Fig. 3. All the ZrO2
films presentation a smooth surface with uniform grains.
In Fig. 3, the surface morphology discovers the nano-crystalline ZrO2 grains, which rise to make intensive films
significantly with the increased thickness. From the images, it was observed that the surfaces of the films exhibited a
confirmed degree of coarseness and the film came rougher when the thickness increases
Fig. (3): AFM images for ZrO2 thin films of thickness85nm and 100nm.
It is observed that the average grain size increases with increasing of thickness and the values of the average grain size
variable from ( 1.97 – 3.71nm) depending on film thickness as shown in table (1) .
Table (1): surface roughness and root square measurements for ZrO2 thin films
Film
Thickness (nm)
Surface Roughness (nm)
RMS (nm)
Grain Size (nm)
85
0.425
0.497
1.97
100
0.512
0.603
3.71
4.CONCLUSION
Zirconium oxide (ZrO2), thin films have been successfully deposited by RF reactive sputtering method on glass
substrates heated at 150 oC. The transmittance is found to increase as the film thickness decrease. AFM images also
support the slow growth of crystallite sizes for the as-grown films and increasing thickness.
Volume 4, Issue 4, April 2015
Page 42
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 4, April 2015
ISSN 2319 - 4847
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Author
AbdulhusseinK.Elttayef, is currently a professor of physics At the Applied physics center,
Baghdad, Iraq. He received his Ph.D Degree from Heriot –Watt University (U.K) in 1990. His
currently research Interests include the preparation of nano films (semiconductors and polymers) by
different methods for applications of gas sensors, solar cells and optical detectors. He has written 40
scientific publications in this area
Prof.Dr.Ahmed K. Abbas , He is Assistant Proff. ,at physics dept., college of science, Wasit university. He is leading
research group in the field of solid state and material Science.
Ghafran .H. Neema M.SC student in physics department, college of science, Wasit University. His research interest
includes the preparation of nano films and applications
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