Fabrication of Ta3N5-Ag nanocomposite thin films with high resistivity and near-zero temperature coefficient of resistance

In this study, we investigate as-deposited Ta3N5-Ag nanocomposite thin films with near-zero temperature coefficients of resistance (TCRs) that are fabricated by a reactive co-sputtering method; these films can be used in thin-film embedded resistors. In these films, the TCR approaches zero due to compensation between Ag (+TCR) and Ta-N (-TCR) at resistivities higher than 0.005 Omega-cm. Taking into account the fact that Ag counterbalances the resistivity of the Ta3N5-Ag thin film, we performed reactive co-sputtering at a nitrogen partial pressure of 55%, corresponding to a resistivity of 0.384 Omega-cm. The resistivity and power density changed, respectively, from 1.333 Omega-cm and 0.44 W/cm(2) for silver to 0.0059 Omega-cm and 0.94 W/cm(2) for the Ta3N5-Ag thin film. A near-zero TCR of +34 ppm/K was obtained at 0.94 W/cm(2) in the Ta3N5-Ag thin film without heat treatment. (c) 2007 Elsevier B.V. All rights reserved.