Influences of Aluminum Doping on the Micro-Structures and Electrical Properties of TaN Thin Films

TaAlN thin films were deposited on Al2O3 substrates by reactive DC magnetron sputtering. The content of Al doping in TaN thin films was controlled by adjusting Al/Ta area ratios of the composite target. The influences of Al/Ta area ratios on the micro-structures and the electrical properties of the samples were investigated in detail. The X-ray diffraction (XRD) results show that AlN (101) and AlN (202) phases precipitate out at 2θ of 38.5° and 65.18° in aluminum doping TaN films, respectively. With the increase of the Al/Ta area ratios, the deposition rate, resistivity and the absolute value of temperature coefficient of resistance (TCR) of the samples increase gradually. When the Al/Ta area ratio is zero, the resistivity and the absolute value of the TCR of the samples are 247.8 μΩ·cm and 12 ppm/℃, wit hr etshpee icnticvreelays.e Hoof wtheev eAr,l/Ta area ratio up to 29%, the resistivity and the absolute value of the TCR of the samples are increased to 2 560 μΩ·cm and 270 ppm/℃, respectively.