Enhanced adhesion strength and solid lubricity of graphite like amorphous carbon films by hydrogen implantation

Abstract

Hydrogen-free graphite-like carbon (GLC) films with columnar nanostructure were modified by hydrogen plasma immersion ion implantation (PIII) at a relatively high pulse voltage of 30 kV. The transition from a columnar nanostructure to a glassy structure in the top layer of the implanted films was firstly observed by transmission electron microscopy . Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was employed to survey the depth profile information of hydrogen (H) and carbon‑hydrogen (C H) bonds, and the results showed that the implanted hydrogen intensively distributed in the glassy layer. The results of Raman spectra showed that disorder of carbon bonds increased and a diamond like carbon structure was derived near the films surface through hydrogen ions implantation. The adhesion strength and tribological performance in nitrogen of GLC were enhanced significantly by hydrogen implantation. • Nano-columnar transferred into glassy structure in hydrogen implanted GLC films. • A hydrogen-rich layer induced by hydrogen implantation. • Adhesion strength enhanced by the hydrogen implantation. • Ultralow stable friction of GLC films in dry nitrogen realized through hydrogen implantation.