Growth and characterization of Al2O3 films on fluorine functionalized epitaxial graphene
Abstract
Intelligent engineering of graphene-based electronic devices on SiC(0001) requires a better understanding of processes used to deposit gate-dielectric materials on graphene. Recently, Al2O3 dielectrics have been shown to form conformal, pinhole-free thin films by functionalizing the top surface of the graphene with fluorine prior to atomic layer deposition (ALD) of the Al2O3 using a trimethylaluminum (TMA) precursor. In this work, the functionalization and ALD-precursor adsorption processes have been studied with angle-resolved photoelectron spectroscopy, low energy electron diffraction, and X-ray photoelectron spectroscopy. It has been found that the functionalization process has a negligible effect on the electronic structure of the graphene, and that it results in a twofold increase in the adsorption of the ALD-precursor. In situ TMA-dosing and XPS studies were also performed on three different Si(100) substrates that were terminated with H, OH, or dangling Si-bonds. This dosing experiment revealed that OH is required for TMA adsorption. Based on those data along with supportive in situ measurements that showed F-functionalization increases the amount of oxygen (in the form of adsorbed H2O) on the surface of the graphene, a model for TMA-adsorption on graphene is proposed that is based on a reaction of a TMA molecule with OH.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 15, 2016
- Source ID
- 10.1063/1.4960803
Entities
People
- Carl A. Ventrice
- Charles. R. Eddy Jr.
- Eng Wen Ong
- Glenn G. Jernigan
- Heike Geisler
- Hongbo Yang
- Ivo Pletikosić
- Sandra C. Hernandez
- Tonica Valla
- Tyler R. Mowll
- Virginia D. Wheeler
- Zachary R. Robinson
Organizations
- Brookhaven National Laboratory
- National Science Foundation
- Office of Naval Research
- SUNY Polytechnic Institute
- State University of New York at Albany
- State University of New York at Brockport
- State University of New York at Oneonta
- United States Naval Research Laboratory