Study of Emission of Light from Nanoporous Silicon Quantum Dot

Beriso, Adem (2010) Study of Emission of Light from Nanoporous Silicon Quantum Dot. Masters thesis, Addis Ababa University.

[img] PDF (Study of Emission of Light from Nanoporous Silicon Quantum Dot)
Adem, Beriso.pdf - Accepted Version
Restricted to Repository staff only

Download (708kB) | Request a copy

Abstract

Both nanocrystalline and nanoporous silicon shows interesting optical and light emission properties. As the system size goes to nanoscale the optical band gap, radiative transitions, oscillator strength, absorption coefficient and dielectric function increases. The nanosilicon shows unusual optical properties which have tremendous importance for nanophotonics and optoelectronic applications. The purpose of the thesis is to study the light emission and optical behavior of nanoporous silicon cluster (quantum dot) with varying porosity and oxygen as well as hydrogen at the surface. We examine these properties combining k.p perturbation method and surface state model. In order to clarify the morphological effects such as size, surface passivation and porosity level of a nanoporous silicon cluster on its optical properties, calculation of optical absorption coefficient, dielectric function and oscillator strength of porous silicon nanoclusters as a function of size (diameter) through energy gap is discussed using k.p method. The effects of nanoparticles size along with surface passivation and porosity level on optical band gap have also been investigated and compared with experiment. The porosity and surface effects are incorporated through some empirical parameters c and α in our model. Furthermore, we examine the main factors that causes photoluminescence peak to shift towards left or to the smaller wavelength of visible spectrum (blue shifted). Our results are in conformity with some other experimental and theoretical findings. We also present some of the important applications of silicon nanostructures and provide a control mechanism for light emission through our investigation.

Item Type: Thesis (Masters)
Subjects: Q Science > Q Science (General)
Q Science > QC Physics
T Technology > T Technology (General)
Divisions: Africana
Depositing User: Selom Ghislain
Date Deposited: 18 Jun 2018 14:04
Last Modified: 18 Jun 2018 14:04
URI: http://thesisbank.jhia.ac.ke/id/eprint/4491

Actions (login required)

View Item View Item