| The rapid development of microelectronic devices will lead to the continuous improvement of device performance and the increase of device integrated on a chip. In order to reduce the RC sign delay, dissipation and cross-talk between metal interconnects caused by size shrinking continuously, people are searching new interlinkaging mode to replace the Al/SiO2 structure, the low dielectric conatant (low-k) materials have received more close attention.Researches indicate that CNX film is one of prospecting low-k materials, which completely meets the requirements of integrated circuit in mechanics performance and chemical stability. We choose p-type doping crystal silicon substrate, with high-purity graphite for the target, high-purity nitrogen and argon gas for work gas. We prapared CNX films by microwave electron cyclotron resonance plasma enhanced unbalance magnetic sputtering with different deposition parameters. We studied the chemical composition, structure, dielectric properties of the films.Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy have been used in order to analyze the chemical structure and properties of films, the dielectric constant and breakdown field were measured by C-V, I-V techniques with Al/CNX/Si (metal-insulate-semiconductor) multilayer structure. In our experiment, we have changed the C target sputtering power to deposit different films. The results showed that the main bonding structures between N and C in the films were C=N and C-N bonds, and the N/C atomic concentration ratio decreased with increasing sputtering power. The dielectric constant of the films measured with a C-V analyzer was typically at the value k～2.4, which is much smaller than that of the conventional SiO2 layers (k～4). The breakdown field of the films measured with a I-V analyzer was typically 0.4MV/cm, which is smaller than the ideal number.
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