Ultra low-k property of hydrogenated carbon nitride: Chemical evaluation

We report that the dielectric constant of hydrogenated carbon nitride (HCNx) film is 1.88 ± 0.06 at 1 kHz at room temperature. The film was deposited on p-Si (1 0 0) wafer by CH4/N2 (1:4) atmospheric pressure dielectric barrier discharge (DBD) plasma. The dielectric constant of HCNx film decreases from 1.88 to 1.71 (±0.06) as the applied frequency increases from 1 kHz to 5 MHz. Round shaped island growth has been observed at film surface area in scanning electron microscopy (SEM). The chemical compositions were investigated by means of X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray (EDX) and elemental analysis.