Fnu Fatima

Date of Award

January 2018

Document Type


Degree Name

Doctor of Philosophy (PhD)


Physics & Astrophysics

First Advisor

Nuri Oncel


Research was carried out on two different topics, metal induced modifications in various cuts of silicon (Si) surfaces and molecular thin films. But both projects reveal the underlying theme of self-assembly. It is needed to discover functional means to create components for integrated circuits as well as electronic and photonic devices since nature can rely upon self-assembly at the nano-scale.

Scanning Tunneling Microscopy and Spectroscopy (STM/STS) studies were performed to characterize the morphology of thin octanoic acid film on graphite and the outcome of 1-deecanethiol adsorption on the electronic properties of iridium (Ir) modified Si (110) surface. It was established that the octanoic acid and 1-decanethiol molecules can create thin films on graphite surface and Ir-modified Si (110) surface respectively. STM and STS measurements were conducted on Ir-modified Si (001) and Si (111) surfaces. The proposed model of Ir-silicide nanowires shows that Ir atoms are found to sit at the top of the dimer rows of Si(100)-2×1. The Ir-modified Si(111) surface revealed domain formation composed of Ir-ring clusters and metallic Ir-silicide islands formation on top of that domain.