Atomic Force Microscopy Investigations on N $^{+}$ Implanted TiN

Thin TiN coatings were implanted with 100 keV N⁺ with ion energy at room temperature using a 150-keV accelerator. Implantation was carried out at three different doses: 5 × 10¹⁵ ions/cm², 1 × 10¹⁶ ions/cm², and 5 × 10¹⁶ ions/cm². For the TiN specimen synthesized by reactive sputtering, nitrogen implantation zones were grey. After implantation, films were characterized by atomic force microscopy (AFM) for topography and Glancing Incident XRD (GIXRD) for possible structural alteration. Examination with GIXRD showed surface amorphization and low angle shift due to enhancement in accumulated compressive stress (~3 GPa). AFM images clearly revealed formation of dissipative structures in the form of ripples. Surface roughness increases from 4.5 to 12.5 nm with ion dose. The mechanism contributing to the enhanced mechanical strength of TiN thin films is explained by using observed nanostructural features. This is the purpose of present investigation.