Tantalum Nitride (TaN) thin films were deposited onto n-type Si(100) and (111) substrates with SiO 2 films at room temperature by radio frequency (RF) magnetron sputtering under Ar-N 2 plasma using a tantalum target. We observed the formation of TaN thin films with a wide range of the electrical resistivity as a function of the N 2 gas flow ratio, working pressure and the sputtering power, and their origins are discussed based upon the structural properties and chemical compositions of TaN thin films before Cu films deposition. In this study, we first observed that the TaN thin films with lower resistivity exhibited TaN (200) preferentially oriented structures and had larger grain sizes. It was also found that the formation of TaO(002) made the resistivity of TaN thin films higher because of the diffusion of oxygen from SiO 2 films during deposition.

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The electrical resistivity and the barrier property of Tantalum nitride (TaN) thin films were systematically investigated as a function of annealing temperature using two different types of MIS structures of TaN/SiO2/Si and Cu/TaN/dielectric/Si(100), where either the thermally grown SiO2 (th-SiO2) or spin-on dielectric (SOD) hydrogen silsesquioxane (HSQ) films was used as a dielectric layer. We observed that the resistivity of TaN thin films before Cu deposition became lower with the growth of TaN (200) as compared with the growth of TaN (111) and TaN(220). Cu diffusion barrier properties of MIS diodes with TaN films were improved up to 500• C for both dielectric films due presumably to the decrease in sputter damage of dielectric films by annealing, while those without TaN thin films were degraded due to the diffusion of Cu into the dielectric films. The oxygen desorption from dielectric films and the oxidation of TaN films due to the reverse-sputtering of dielectric films during the sputtering of Ta in N2 is possible model of sputter damage.