The barrier properties of PVD deposited tantalum nitride barrier films on a substrate are improved by biasing the substrate during deposition and wherein the bulk of the barrier film is TaNx wherein x is less than or equal to 1 and the barrier film has a resistivity of up to about 500 microohms-cm. A continuous method for depositing tantalum nitride layers on successive substrates stabilizes a flow of argon gas alone in the chamber, sputter deposits a first layer of tantalum or a tantalum-rich layer, then adds nitrogen to deposit tantalum nitride while biasing the substrate and maintaining a high nitrogen content in the film, and, by shutting off the flow of nitrogen, deposits tantalum or a tantalum-rich film to remove any tantalum nitride deposits on the surface of the tantalum target. This method avoids hysteresis drift of the composition and properties of the barrier films over successive depositions.
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