Optimization of energy and fluence of N-2(+) ions in the conversion of Al2O3 surface into AIN at room temperature

Abstract

The work presents a systematic study of energetic N-2(+) ion interaction with the clean Al2O3 surface at room temperature. Energetic N-2(+) ions with energies ranging from 0.1 to 5 keV were bombarded onto the c-plane Al2O3 surface in situ in a UHV system equipped with X-ray Photoelectron Spectroscopy. Survey scans and core level spectra of Al(2p), O(1s), N(1s) were recorded as a function of ion fluence. Survey scans of XPS are used for the compositional analysis, while deconvoluted core level spectra are used to identify the evolution of the chemical bonding. Energetic dependence of N-2(+) ions occupying interstitial and substitutional sites in Al2O3 lattice are probed to follow the surface evolution. Results show that maximum thickness of surface is nitride by 5 keV N-2(+) ion with an optimal fluence of 1.5 x 10(15) ions/cm(2). This modified surface can be used as a template for low defect III-nitrides growth, with enhanced lattice matching than on bare c-Al2O3. (C) 2015 Elsevier B.V. All rights reserved.