Influence of NH 3 plasma treatment on chemical bonding and water adsorption of low-k SiCOH film

Abstract

Carbon-doped silicon oxide (SiCOH) dielectrics are one of the most suitable candidates for advanced low-dielectric-constant (low-k) interlayer material. To improve water adsorption resistance, the plasma-enhanced chemical vapor deposited SiCOH films have been post-treated by the NH 3 plasma for various times, and the resulting SiCOH films are thus examined by water adsorption experiments. The results indicate that the SiCOH films treated by the NH 3 plasma exhibit enhanced resistance against water adsorption. Further, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy are used to characterize the chemical composition and bonding states of the pristine and NH 3 plasma treated SiCOH films. It is revealed that the plasma surface treatment leads to the formation of Si–N, C(sp 3)–N, C(sp 2) N, (N–) n Si–C ( n = 1–3) configurations, and loss of carbon atoms.