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conferenceseries
.com
Volume 4, Issue 4 (Suppl)
J Laser Opt Photonics, an open access journal
ISSN: 2469-410X
Optics 2017
November 15-17, 2017
November 15-17, 2017 | Las Vegas, USA
8
th
International Conference and Exhibition on
Lasers, Optics & Photonics
Spectroscopic phonon and extended x-ray absorption fine structure measurements on 3C-SiC/Si (001)
epifilms
Devki N Talwar
Indiana University of Pennsylvania, USA
C
omprehensive experimental and theoretical studies are reported to assess the vibrational and structural properties of 3C-SiC/Si
(001) epilayers grown by chemical vapor deposition in a vertical reactor configuration. While the phonon features are evaluated
using high resolution infrared reflectance (IRR) and Raman scattering spectroscopy (RSS) the local inter-atomic structure is appraised
by synchrotron radiation extended x-ray absorption fine structure (SR-EXAFS) method. Unlike others, our RSS results in the near
backscattering geometry revealed markedly indistinctive longitudinal and transverse-optical phonons in 3C-SiC epifilms of thickness
d<0.4 μm. The estimated average value of biaxial stress was found to be an order of magnitude smaller while the strains were two-
orders of magnitude lower than the lattice misfits between 3C-SiC and Si bulk crystals. Bruggeman’s effective medium theory was
utilized to explain the observed atypical IRR spectra in 3C-SiC/Si (001) epifilms. High density intrinsic defects present in films and/
or epilayer/substrate interface were likely to be responsible for (a) releasing misfit stress/strains, (b) triggering a typical features in IRR
spectra and (c) affecting observed local structural traits in SR-EXAFS.
Biography
Devki N Talwar graduated fromAllahabad University in India in 1976 with a PhD degree in Condensed Matter Physics. From 1977-80 he worked as a Visiting Scientist at the
Commissariat a’l Energie Atomic, Saclay, Gif-sur-Yvette, France with M Vandevyver. While at Saclay he collaborated with theoretical /experimental group of M Balkanski,
including Karel Kunc, M Zigone and G Martinez and supervised three PhD theses. In January 1980 he joined the Physics Department, University of Houston as a Visiting
Professor and collaborated with P C S Ting on problems related to the electronic properties of defects in semiconductors and supervised a PhD student. From 1982-87 he
was a Faculty at Texas A & M University. He joined the Physics Department at Indiana University of Pennsylvania in 1987, supervised 20 MS theses. Since 2007-2014, he
has served as the Chairperson of the Physics Department.
talwar@iup.eduDevki N Talwar, J Laser Opt Photonics 2017, 4:4 (Suppl)
DOI: 10.4172/2469-410X-C1-017