title: The influence of high dielectric constant aluminum oxide sputter deposition on the structure and properties of multilayer epitaxial graphene.
abstract: High dielectric constant aluminum oxide (Al(2)O(3)) is frequently used as the gate oxide in high electron mobility transistors and the impact of its deposition by radio frequency (RF) magnetron sputtering on the structural and electrical properties of multilayer epitaxial graphene (MLG) grown by graphitization of silicon carbide (SiC) is reported. Micro-Raman spectroscopy and temperature dependent Hall mobility measurements reveal that the processing induced changes to the structural and electrical properties of the MLG can be minimal when the oxide deposition conditions are optimal. High-resolution transmission electron microscopy (HRTEM) analysis confirms that the Al(2)O(3)/MLG interface is relatively sharp and that our thickness approximation of the MLG using angle resolved x-ray photoelectron spectroscopy (ARXPS) is accurate. An interface trap density of 5.1 × 10(10) eV(-1) cm(-2) was determined using capacitance-voltage techniques. The totality of our results indicates that ARXPS can be used as a nondestructive tool to measure the thickness of MLG, and that RF sputtered Al(2)O(3) can be used as a high dielectric (high-k) constant gate oxide in multilayer graphene based transistor applications.
authors: Department of Materials Science and Engineering, University of North Texas, Denton, TX 76203, USA.
authors: Mohammad H
authors: MH
authors: Maneshian
authors: Fang-Ling
authors: FL
authors: Kuo
authors: Kristopher
authors: K
authors: Mahdak
authors: Junyeon
authors: J
authors: Hwang
authors: Rajarshi
authors: R
authors: Banerjee
authors: Nigel D
authors: ND
authors: Shepherd