Irradiation induced formation of VN in CrN thin films

Abstract

Reactively sputtered CrN layer, deposited on Si(100) wafer, was implanted at room temperature with 80-keV V+. ions to the fluence of 2 x 10(17) ions/cm(2). After implantation the sample was annealed in a vacuum, for 2 h at 700 degrees C. The microstructure and chemical composition of CrN films was investigated using Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy (conventional and high-resolution), together with fast Fourier transformation analyses. It was found that vanadium atoms are distributed in the sub-surface region of CrN layer, with the maximum concentration at similar to 20 nm. After annealing the formation of VN nanoparticles was observed. The nanoparticles are spherical shaped with a size of 8-20 nm in diameter. (C) 2015 Elsevier B.V. All rights reserved.