Interplay of Electrical, Mechanical and Thermal Fields in III-N Nanostructures for LED Applications

This work aims at exploring the competing effects of various internal/built-in fields on the electronic structure and optical properties of III-N nanostructured (Quantum Dots and disk-in-a-wire) LEDs using a multiscale modeling approach. The objective is three-fold: (1) calculate the strain distribution, optical transition rates and one-particle electronic states using a 10-band sp<super>3</super>s<super>*</super> tight-binding framework; (2) to compute the effects of piezoelectric and pyroelectric polarization on the optical transition rates; (3) to model piezoelectricity in the wurtzite lattice, we have considered four different polarization models (based on the experimental /bulk and ab initio coefficients) in increased order of accuracy; (4) to study the origin and effects of these four competing internal fields on the electronic structure of self-assembled InN/GaN quantum dots having three different geometries, namely, box, dome, and pyramid; (5) integrating the NEMO3-D with commercial TCAD tool Synopsys to determine the terminal electrical and optical characteristics of InGaN/GaN disk-in-a-wire LEDs; and (6) finally to propose optimum device specifications for InGaN/GaN disk-in-a-wire LEDs to achieve maximum Internal Quantum Efficiency (IQE).

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Campus Only Dissertation

Discipline thesis:degree_discipline

Electrical and Computer Engineering

Year

2013

Author dc:creator

• Yalavarthi, Krishna Kumari

Contributors dc:contributor

• Ahmed, Shaikh

Repository record dc:identifier

https://opensiuc.lib.siu.edu/dissertations/708

OAI identifier oai:identifier

oai:opensiuc.lib.siu.edu:dissertations-1710