Characteristics of TiN films deposited on a trench-shaped sample prepared by plasma-based ion implantation and deposition

Titanium nitride (TiN) film was deposited on the trench surface by plasma-based ion implantation and deposition (PBII&D) technique using a titanium cathodic arc discharge at a nitrogen pressure of 8 Pa at a process time of 2 h. The trench size was 100 mm in length and 50 mm in depth for two widths of 10 and 30 mm. During the process, a train of negative voltage pulses of 5 kV with a pulse width of 20 μs at a repetition rate of 400 Hz was applied to the substrate. The plasma density in front of the trench was about 1010 ions/cm3. In order to analyze the deposited films, silicon (111) wafers were pasted on the trench walls. Glancing angle X-ray diffraction (GXRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM) and nano-indentation system were used to analyze the prepared films. It was found that the thickness of the films largely changed from the top to the bottom of the trench. The distribution of the plasma species inside the trench influenced to the deposition rate. Analysis by nano-indenter showed that the hardness and elastic modulus of the prepared films were about 20–35 GPa and about 400 GPa, respectively. The structure of the films deposited on the trench surface is titanium nitride, which has a (200) preferred orientation on the bottom and the top of the trench, while a (111)-preferred orientation is recognized at the side wall.