Atmospheric Pressure Plasma CVD of Amorphous Hydrogenated Silicon Carbonitride (aSiCN:H) Films Using Triethylsilane and Nitrogen

Amorphous hydrogenated silicon carbonitride (a-SiCN:H) thin films are synthesized by atmospheric pressure plasma enhanced chemical vapor (AP-PECVD) deposition using the Surfx Atomflow 250D APPJ source with triethylsilane (HSiEt3, TES) and nitrogen as the precursor and the reactive gases, respectively. The effect of the substrate temperature (Ts) on the growth characteristics and the properties of a-SiCN:H films was evaluated. The properties of the films were investigated via scanning electron microscopy (SEM), atomic force microscopy (AFM) for surface morphological analyses, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) for chemical and compositional analyses; spectroscopic ellipsometry for optical properties and thickness determination and nanoindentation to determine the mechanical properties of the a-SiCN:H films. Films deposited at low Ts depict organic like features, while the films deposited at high Ts depict ceramic like features. FTIR and XPS studies reveal that an increases in Ts helps in the elimination of organic moieties and incorporation of nitrogen in the film. Films deposited at Ts of 425 8C have an index of refraction (n) of 1.84 and hardness (H) of 14. 8 GPa. A decrease in the deposition rate between Ts of 25 and 250 8C and increase in deposition rate between Ts of 250 and 425 8C indicate that the growth of a-SiCN:H films at lower Ts are surface reaction controlled, while at high temperatures film growth is mass-transport controlled. Based on the experimental results, a potential route for film growth is proposed.