Benoy, M D; Dr.Pradeep, B(Cochin University of Science and Technology, May 7, 2001)
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Abstract:
The investigation of physical properties of matter has progressed so much
during the last hundred years. Today physics is divided in to a large distinct group
of special branches. These branches are distinguished by the particular area
studied, method of investigation and so on. An independent and important branch
that has developed is the physics ofthin films.Any object in solid or liquid form with one of its dimensions very much
smaller than that of the other two may be called a thin film. It is having only one
common property, namely, one of their dimensions is very small, though all their
physical properties may be different. Thin layers of oil, floating on the surface of
water, with their fascinating colours, have attracted men’s curiosity from time
immemorial. The earliest application of thin films was the protective coatings in
the form of paints. A thin layer of tin has been used from ancient times to protect
copper utensils from corrosion. Indium thin films are used in certain applications
on account of their good lubricating property. Relay contacts are coated with thin
films of rare earth metals in order to prevent burning due to arcing. Hard coatings
are also available using diamond like carbon (i-carbon). The basic properties of
thin films are of considerable interest because of their potential applications in
various fields of science and technology
Description:
Department of Physics, Cochin University of Science And
Technology
Jayaraj, M K(Electrochemical Society, February 18, 2008)
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Abstract:
The optical and carrier transport properties of amorphous transparent zinc indium tin oxide (ZITO)(a-ZITO) thin films and the
characteristics of the thin-film transistors TFTs were examined as a function of chemical composition. The as-deposited films
were very conductive and showed clear free carrier absorption FCA . The analysis of the FCA gave the effective mass value of
0.53 me and a momentum relaxation time of 3.9 fs for an a-ZITO film with Zn:In:Sn = 0.35:0.35:0.3. TFTs with the as-deposited
channels did not show current modulation due to the high carrier density in the channels. Thermal annealing at 300°C decreased
the carrier density and TFTs fabricated with the annealed channels operated with positive threshold voltages VT when Zn
contents were 25 atom % or larger. VT shifted to larger negative values, and subthreshold voltage swing increased with decreasing
the Zn content, while large on–off current ratios 107–108 were kept for all the Zn contents. The field effect mobilities ranged
from 12.4 to 3.4 cm2 V−1 s−1 for the TFTs with Zn contents varying from 5 to 48 atom %. The role of Zn content is also
discussed in relation to the carrier transport properties and amorphous structures.
Nithyaja, Balan; Misha, Hari; Nampoori, Vadakkedathu P N(Optical Society of America, July 1, 2009)
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Abstract:
A solid-state laser based on a dye-doped deoxyribonucleic acid (DNA) matrix is described. A thin solid film of DNA has been fabricated by treating with polyvinyl alcohol (PVA) and used as a host for the laser dye Rhodamine 6G. The edge emitted spectrum clearly indicated the existence of laser modes and amplified spontaneous emission. Lasing was obtained by pumping with a frequency-doubled Nd:YAG laser at 532 nm. For a pump energy of 10 mJ/pulse, an intense line with FWHM ≈0.2 nm was observed at 566 nm due to selective mode excitation.
Junaid, Bushiri M; Gopakumar, V; Vaidyan, V K(January 17, 2013)
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Abstract:
ZnO thin films were coated on amorphous glass substrate at various temperatures in the
range 160-500 0C by spray pyrolysis method. The as deposited films were characterised by
using XRD and SEM. Wurtzite phase of ZnO was formed at a substrate temperature of
400 0C, highly oriented (002) phase was developed with respect to increase of substrate
temperature from 450 to 500 0C. Morphological and growth mode of these films were
analyzed with respect to structural orientation of films from wurtzite to highly (002)
oriented phase. Present study reveals that substrate temperature was one of the important
parameters which determine the crystalline quality, population of defects, grain size,
orientation and morphology of the films
Description:
Journal of Optoelectronics and Biomedical Materials Vol. 5 Issue 1, January - March 2013 p. 1 - 8