Fabrication of Ta 3N 5–Ag nanocomposite thin films with high resistivity and near-zero temperature coefficient of resistance

Abstract

In this study, we investigate as-deposited Ta 3N 5–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 Ω-cm. Taking into account the fact that Ag counterbalances the resistivity of the Ta 3N 5–Ag thin film, we performed reactive co-sputtering at a nitrogen partial pressure of 55%, corresponding to a resistivity of 0.384 Ω-cm. The resistivity and power density changed, respectively, from 1.333 Ω-cm and 0.44 W/cm 2 for silver to 0.0059 Ω-cm and 0.94 W/cm 2 for the Ta 3N 5–Ag thin film. A near-zero TCR of + 34 ppm/K was obtained at 0.94 W/cm 2 in the Ta 3N 5–Ag thin film without heat treatment.