RBS, AES and XRD investigations of high-dose nitrogen-implanted Ti, Cr, Fe, Zr and Nb sheets

Abstract

A study has been made of the crystal structure and depth profile of nitrogen in Ti, Cr, Fe, Zr and Nb sheets of 1 mm thickness with a purity of 99.9%, implanted with a high nitrogen dose. The ion implantation of 14 N + was performed with a dose of 1 × 10 18 ions/cm 2 at an energy of 100 keV at room temperature. The crystal structure of nitrogen-implanted layers was estimated by means of X-ray diffraction (XRD). Analyses of Auger electron spectroscopy (AES) combined with 3 keV Ar + sputtering and Rutherford backscattering spectrometry (RBS) using 1.5 MeV 4 He + ions were employed in order to determine the nitrogen depth profiles of implanted layers. XRD patterns indicated the formation of such nitrides as TiN, CrN, Fe 2 N and ZrN. AES and RBS studies revealed that implanted nitrogen forms a trapezoidal distribution, whereas the atomic ratio of nitrogen to metals at flat-topped plateaux estimated by RBS is larger than those obtained by AES. The deviation corresponded to the increase in the substrate atomic number. The relations among RBS, AES and XRD results will be discussed.