Studies On Ti-Si-N Thin Film Material With Composition Spread Method

In this thesis work, thin films related to SiNx, TiN and Ti-Si-N compounds were prepared by the microwave electron cyclotron resonance (MW-ECR) plasma enhanced unbalanced magnetron sputtering of Si and Ti targets in Ar/N2 circumstances. A profiler and a nano-indentator were used to measure the film thickness and hardness, respectively, and Fourier transform infrared spectroscopy, an X-ray diffractometry and X-ray photoelectron spectroscopy were used to study chemical binding, the structure and composition of the film. The results indicated as follows:When SiNx films were prepared by magnetron sputtering with Si target, nitrogen and argon, the deposition temperature, N2 flow rate and the sputtering powers of Si target all have influences on the hardness of deposited films. The hardness of SiNx thin films increased significantly with the rise of the substrate temperature; with the significant value of 35GPa being obtained at the highest temperature of 694℃. The hardness of SiNx thin films decreased gradually with the escalation of N2 flow rate, keeping the sputtering powers of Si targets and the argon flow constant. The Si-N stretching vibration peak and the density of Si-N bond reached their maximum when the N2 flow rate was 2sccm, so the hardness of the thin film reached the significant value of 33.6GPa. The sputtering power of Si target changed while the other experiment parameters being constant, the hardness of the SiNx thin film decreased monotonically with the increase of the sputtering powers of Si target.When TiN films were prepared by magnetron sputtering with Ti target, nitrogen and argon, the N2 flow rate had evident influence on the deposition rate, the structure and resistivity of the thin films. With the increase of N2 flow rate, the deposition rate of the TiN thin film first increased and then decreased rapidly. The deposition rate reached the maximum value of 10.5nm/min when the N2 flow rate was 1.5 sccm. With the increase of N2 flow rate, the intensity of the diffraction on the TiN (111) direction of the crystal plane didn't change significantly. The intensity of the diffraction on the TiN (220) direction of the crystal plane first increased and then decreased gradually. When the N2 flow rate was 1.5 sccm, the TiN preferred a growth orientation along the (220) direction. As the N2 flow rate increases, the resistance rate of the thin film monotonically increased from 3.35×10-4Ω·cm to 1.74×10-3Ω·cm.We found that changes in the film composition had important effect on the structure and hardness, when the component extended Ti-Si-N films were prepared by mask confined continuous composition spread thin film material library technology. With the increase of the Si content and the decrease of the Ti content, the interface phase in the substrate presented a preferred orientation growth of (220) in the TiN and a (411) in theα-Si3N4, and the TiN and a-Si3N4 crystal phase on the interface phase formed epitaxial coherent growth. With the decrease of the Si-to-Ti ratio, the hardness of the thin films showed a trend of rise, when the Si-to-Ti ratio of 0.05, the film contained the structure of crystalline TiN and amorphous a-Si3N4, so the film reached a maximum hardness of 43.8GPa.