Suppression of subcutaneous oxidation during the deposition of amorphous lanthanum aluminate on silicon

Department of Physics, North Carolina State University, Raleigh, North Carolina, United States
Applied Physics Letters (Impact Factor: 3.3). 06/2004; 84(23). DOI: 10.1063/1.1759065
Source: OAI


Amorphous LaAlO(3) thin films have been deposited by molecular beam deposition directly on silicon without detectable oxidation of the underlying substrate. We have studied these abrupt interfaces by Auger electron spectroscopy, high-resolution transmission electron microscopy, medium-energy ion scattering, transmission infrared absorption spectroscopy, and x-ray photoelectron spectroscopy. Together these techniques indicate that the films are fully oxidized and have less than 0.2 A of SiO(2) at the interface between the amorphous LaAlO(3) and silicon. These heterostructures are being investigated for alternative gate dielectric applications and provide an opportunity to control the interface between the silicon and the gate dielectric. (C) 2004 American Institute of Physics.

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