| AVS 64th International Symposium & Exhibition | |
| Spectroscopic Ellipsometry Focus Topic | Monday Sessions |
| Session EL+AS+EM+TF-MoM |
| Session: | Application of SE for the Characterization of Thin Films and Nanostructures |
| Presenter: | Daniel Fullager, University of North Carolina at Charlotte |
| Authors: | D. Fullager, University of North Carolina at Charlotte G. Boreman, University of North Carolina at Charlotte T. Hofmann, University of North Carolina at Charlotte C.R. Ellinger, Eastman Kodak Company |
| Correspondent: | Click to Email |
Transparent conductors for displays, backplanes, touchscreens and other electronic devices are an area of active research and development; in this manner, aluminum-doped zinc oxide (AZO) has shown promise as an ITO replacement for some applications. Although there have been numerous reports on the optical properties and electrical conductivity of AZO, there has not yet been a Kramers-Kronig consistent dispersion model fully describing the charge carrier dynamics. In this presentation, we will report on the model dielectric function of AZO from the combination of UV-Vis and IR spectroscopic ellipsometry. A model dielectric function that describes the optical response over this wide spectral range will be presented and discussed. In particular, we will present a comparison between the commonly used extended Drude models and the dielectric function developed here in light of results obtained from density functional theory calculations.
The AZO films analyzed in this study were deposited using a spatial atomic layer deposition (SALD) process. While AZO can be deposited by several techniques, including sputtering, chemical vapor deposition (CVD), and atomic layer deposition (ALD), ALD does allow for the greatest ability to control the aluminum-doping level of AZO. However, the range of substrate sizes and form factors addressable by traditional chamber ALD are limited. Conversely, spatial ALD (SALD) is an atmospheric pressure, roll-compatible ALD process that enables the materials property control of ALD to be translated into a wider range of applications spaces. Furthermore, the use of selective area deposition in a “patterned-by-printing” approach enables the high-quality AZO deposited by SALD to be easily patterned, offering an integrated and facile path for manufacturing optical and electronic devices.