ABSTRACT OF THE DISSERTATION
Thermoelectric and electrical characterization of Si nanowires and
GaNAs
by
Paothep Pichanusakorn
Doctor of Philosophy in Materials Science and Engineering
University of California, San Diego, 2012
Professor Prabhakar R. Bandaru, Chair
Thermo-electricity offers an elegant solution to the problem of heat-toelectricity
conversion. As a completely solid-state heat engine, thermoelectric materials
confer many advantages in electricity generation and heat pumping. However,
the efficiency of thermoelectric material, represented by the figure of merit,
Z, is generally low. In order to increase Z, it is desirable to increase a property
of material known as the density of states (DOS). In this work, two approaches to
increase DOS were explored, one based on the physical effect of quantum confinement
in Si nanowires, and another based on the chemical approach where by GaAs
property are drastically changed by doping of N. While the Si nanowires fabrication
have proved to be extremely challenging, and results were hard to obtain, some