Eur. Phys. J. Plus (2015) 130: 29
https://doi.org/10.1140/epjp/i2015-15029-1

Regular Article

The effect of bias voltage on microstructure and hardness of TiN films grown by ion coating deposition

¹ Nuclear Science & Technology Research Institute, Physics and Accelerators School, Karaj, Iran
² Nuclear Science & Technology Research Institute, Radiation Application Research School, Karaj, Iran
³ Department of Physics, Payamnoor University of Tehran- Shargh, Tehran, Iran
⁴ Department of Physics, University of Kashan, Kashan, Iran
⁵ Department of Materials engineering, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran

^* e-mail: mmojtahedzad@gmail.com

Received: 22 April 2014
Revised: 14 November 2014
Accepted: 5 January 2015
Published online: 24 February 2015

Abstract

Titanium nitride (TiN) thin films were grown onto 316 stainless steel substrate at 350 ^° C by hollow cathode discharge ion plating technique. Since microstructure and mechanical properties of the samples were strongly affected by bias voltage, different bias voltages from 0 to | − 120| V were applied to the substrate. Rutherford back-scattering spectroscopy showed that the film thickness decreased when the bias voltage increased. X-ray diffraction patterns showed that the as-prepared TiN thin films were preferentially grown in the (200) direction with a satisfactory crystal quality at −30 V. The spatial scaling behavior of the TiN films grown by ion coating have been investigated by using the atomic force microscopy as well as a kinetic roughening model for the film thickness ranging from 380 to 590nm. The roughness and dynamic scaling exponents have been independently measured (α = 0.7 ± 0.05 and Z = 3.03 ± 0.05) and they exhibited a smooth surface growth. Nanohardness showed formation of a film with 30GPa hardness and 285 GPa Young modulus at −30 V bias voltage.