| The structural modulability and chemical stability of hydrogenated amorphous Silicon Carbide (a-SixC1-x:H) films makes it suitable as a barrier layer for low K porous dielectric films. We have prepared it using micro-wave electron cyclotron resonance chemical vapor deposition(ECRCVD) method under different substrate temperature and gas flow ratios R {R=[CH4]/([CH4]+[SiH4]+[Ar])}. The plasma properties, structural evolution and properties of the prepared a-SixC1-x:H films were investigated by an optical emission spectroscopy (OES), Fourier transform infrared spectroscopy (FTIR) and ultraviolet visible (UV-VIS) spectrometer, respectively.Results shows that: H and CH emission intensities increase with R while that of SiH decrease; the a-SixC1-x:H films turned from silicon-rich state to carbon-rich state with the increase of R, it is speculated that the phase and composition evolution of the a-SixC1-x:H film is the critical factor which leads to the change of the film's optical band gap and dielectric constant; the lekage current of low K porous SiCOH films is much decreased while the dielectric constant doesn't change by depositing a 20nm thick a-Si1-xCx:H film at R equals to 0.65 and substrate temperature is 350℃... |
