dc.contributor.advisor | Aydınlı, Atilla | |
dc.contributor.author | Gündoğdu, Sinan | |
dc.date.accessioned | 2016-01-08T18:24:51Z | |
dc.date.available | 2016-01-08T18:24:51Z | |
dc.date.issued | 2012 | |
dc.identifier.uri | http://hdl.handle.net/11693/15801 | |
dc.description | Ankara : The Department of Physics and the Graduate School of Engineering and Science of Bilkent University, 2012. | en_US |
dc.description | Thesis (Master's) -- Bilkent University, 2012. | en_US |
dc.description | Includes bibliographical references leaves 77-81. | en_US |
dc.description.abstract | Silicon nanocrystals are well known to exhibit strong luminescence in the visible.
Extension of this into a nanocrystal network would be beneficial for many
applications. In the light of recent advances on exciton-plasmon interactions and
photovoltaic cells, there is renewed interest in the use of nanostructures. Due to
quantum confinement, silicon nanoclusters with increased band gaps, are promising
for down conversion light and enhanced emission on plasmonic surfaces. Conventional
techniques utilize high-temperature processing to obtain the Si-SiO2
phase separation which uses high thermal budget, not suitable for localized applications
not compatible with glass substrates or thin-film stacked structures.
An alternative approach capable of avoiding high temperature processing is laser
irradiation of substochiometric amorphous silicon oxides.
In this work, continuous-wave laser processing of Si-rich oxide thin films with
varying Si content were performed in order to obtain Si nanocrystals embedded in
silica. The role of composition, dwell times and power densities were investigated
for Si-SiO2 phase separation.
We present cw laser processing of PECVD grown and sputtered SiOx films.
XPS, RBS and ERDA techniques were used for the stoichiometry analysis of different
composition as grown samples and their optical properties were determined
through ellipsometry analysis. Processing was performed with an Ar+ laser at
488 nm. The structural changes due to processing were investigated by Raman
and photoluminescence spectroscopy. It has been shown that silicon nanocrystals
formation depends both on precursor gas composition (hydrogen-diluted SiH4 and
N2O or CO2 gases) and on laser power density. PECVD grown hydrogenated SiOx
films were compared with sputtered films with and without hydrogen to identify
the role of hydrogen for phase separation. | en_US |
dc.description.statementofresponsibility | Gündoğdu, Sinan | en_US |
dc.format.extent | xv, 88 leaves, illustrations, graphics | en_US |
dc.language.iso | English | en_US |
dc.rights | info:eu-repo/semantics/openAccess | en_US |
dc.subject | silicon rich oxides | en_US |
dc.subject | thin film | en_US |
dc.subject | laser anealing | en_US |
dc.subject.lcc | TA418.9.T45 G85 2012 | en_US |
dc.subject.lcsh | Thin films. | en_US |
dc.subject.lcsh | Silicon | en_US |
dc.subject.lcsh | Oxidation. | en_US |
dc.subject.lcsh | Nanocrystals. | en_US |
dc.title | Formation of silicon nanocrystals by laser processing of silicon rich oxides | en_US |
dc.type | Thesis | en_US |
dc.department | Department of Physics | en_US |
dc.publisher | Bilkent University | en_US |
dc.description.degree | M.S. | en_US |