TaSiN diffusion barriers deposited by reactive magnetron sputtering

Due to its resistance to oxidation, TaSiN is a promising candidate as an electrically conductive barrier layer for integration of high permittivity oxides in advanced memory devices. In this study we report on the properties of TaSiN thin films deposited by reactive magnetron sputtering of a TaSi2 target in an Ar/N2 atmosphere. We especially focus on the influence of deposition parameters (pressure and power density) on TaSiN film properties. To study oxidation resistance, films are processed by rapid thermal annealing in 18O2 at 650 °C. The concentration depth profiles of 18O were measured via the narrow resonance of 18O(p,α)15N at 151 keV (FWHM = 100 eV). Whatever the power density, films deposited above 2 Pa are porous and exhibit high resistivity. Ta26Si47N27 deposited at 0.5 Pa with a power density of 2.65 W/cm2 exhibits high density, low resistivity, and good oxidation resistance.