High-rate synthesis of SiCN films using single-source silicon precursor with high-density helicon plasma

Abstract

A novel type of compound, namely Si-guanidinate, where the Si center of alkylsilyl is linked with pyrrolyl-guanidinate ligand, has been synthesized as potential chemical vapor deposition (CVD) precursor and characterized by 1H, 13C, EI-MS, and elemental analysis. The thermal properties of the Si-guanidinate, including vapor pressure and thermal stabilities which were investigated by simultaneous thermal analyses (STA) exhibit a promising precursor in CVD process. The Si-guanidinate was used as a single-source liquid organosilicone precursor to deposit silicon carbon nitride (SiCN) films with the helicon plasma-enhanced chemical vapor deposition (HWP-CVD) method. The effect of the substrate pules negative bias voltage (-Vs) on the microstructure, morphology, composition and optical properties (including refractive index) of the SiCN films has been studied. The deposition rate of the films exhibits a maximum of 15.3 μm/min, which is contributed by the high-density plasma generation of HWP. By X-ray photoelectron spectroscopy (XPS) analysis, the film is mainly composed of Si–C–N. The SiCN films deposited at -VS of 1500 V appear to be high N content of 30.0% (k = 1.83) materials with quite small surface roughness (Root mean square (RMS)~0.7 nm).