Date of Award




Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Nanoscale Science and Engineering


Nanoscale Engineering

Content Description

1 online resource (ii, 154 pages) : illustrations (some color)

Dissertation/Thesis Chair

Pradeep Haldar

Committee Members

Harry Efstathiadis, Alain Diebold, Mengbing Huang, John Zeller


CIGS, Damp-heat stable, Photovoltaics, Reliability, Room temperature depositions, Transparent Conducting Oxides, Solar cells, Photovoltaic cells, Thin film devices, Copper indium selenide, Gallium alloys, Zirconium, Semiconductor doping

Subject Categories

Materials Science and Engineering | Nanoscience and Nanotechnology


Photovoltaic devices are among the promising options for sustainable future energy generation. Thin film solar cells have demonstrated the ability to be a low-cost solution to clean renewable energy and are cost competitive with current silicon based photovoltaic devices. One of the most promising thin film devices right now is the Copper Indium Gallium Selenide (CIGS) solar cell with maximum reported power conversion efficiency of 22.3%. The Transparent Conducting Oxide (TCO) which is the top layer of the CIGS device also known as the window layer, is responsible for collecting the electrons generated in the CIGS device and conducting them to the circuit. Development of a very low resistivity film with a high optical transmission is crucial for optimal performance of devices as well as the ability to be deployed without changes to their properties for several decades. Current TCOs such as indium tin oxide (ITO) and aluminum doped zinc oxide (AZO) are met with limitations with either using large amounts of expensive materials such as indium, often requiring and anneal step to obtain good conductivity, or have shown poor long term reliability. This thesis is focused on development of InZnO and zirconium doped InZnO as a potential replacement TCO to obtain high conductivity and high transmission like the leading TCOs without needing heated depositions, post deposition annealing, and maintain a good film reliability. Zirconium doping was employed to farther enhance both the optical and electrical properties through enhancement of the films high frequency permittivity of InZnO while providing improved reliability to the film.