Tantalum nitride thin films were deposited on SiO2 (600nm)/Si substrates at various nitrogen/argon ratios [N-2/(N-2 + Ar)] by dc magnetron sputtering. The structural and electrical properties of the films are investigated as a function of nitrogen/argon ratio at room temperature and at various deposition temperatures. The phase changes as Ta2N or TaN in the films were observed as nitrogen/argon ratio increases from 3 to 25%. The phase changes were associated with a change in the resistivity and TCR (temperature coefficient of resistance) of the films. TCR values of the films deposited at room temperature and different nitrogen contents were negative, and strongly decreased with the increase in nitrogen/argon ratio. The Ta2N films deposited at a nitrogen/argon ratio of 3% show higher TCR values and thermal stability of the resistance in the 25-120 degrees C temperature range. The Ta2N films deposited at a nitrogen/argon ratio of 3% and a temperature of 200 degrees C showed a TCR value of -47 ppm/K, which is close to near-zero TCR in the range of deposition temperature. (c) 2006 The Electrochemical Society.