AVS 45th International Symposium
    Thin Films Division Monday Sessions
       Session TF-MoM

Paper TF-MoM5
Photoemission Spectroscopy Analysis of ZnO Films for Display Applications

Monday, November 2, 1998, 9:40 am, Room 310

Session: Transparent Conductive Oxides
Presenter: G.S. Tompa, Structured Materials Industries, Inc.
Authors: E.W. Forsythe, University of Rochester
Y. Gao, University of Rochester
G.S. Tompa, Structured Materials Industries, Inc.
L.G. Provost, Structured Materials Industries, Inc.
J. Doyle, Advanced Display Systems
Correspondent: Click to Email
An important factor in the performance of most displays is the quality of at least one transparent conductive oxide contact layer. Presently, indium tin oxide (ITO) is predominantly used because it is an accepted standard and has a great deal of invested development. However, for several reasons, including work function, physical stability, and band alignment, ITO is not always the ideal contact layer for a given display technology. We will report the physical properties of ZnO based films prepared by metal organic chemical vapor deposition (MOCVD) using ultraviolet and x-ray photoemission spectroscopy (UPS and XPS). In addition, the surface characteristics of the films are modified with series of cleaning and polishing steps. Using UPS, the work function for ZnO is 4.23eV. XPS results show an oxide layer more than 5nm on the surface of the as-received MOCVD films, with a small fraction of Zn and Ga. This oxide layer is removed by a cleaning and plasma treatment, which enhances the conductivity of the ZnO films. Finally, we will report atomic force microscopy results before and after cleaning and polishing as well as chemical etching results. This work was supported in part by DARPA DAAL01-96-K-0086, NSF DMR-9612370.