Structure and physical properties of polycrystalline hexagonal Ta2N films deposited by reactive sputtering

Abstract

Hexagonal-structure polycrystalline Ta2N films with (213̄1) preferred orientation were deposited by reactive sputter deposition onto glass substrates in mixed Ar/N2 atmospheres. Transmission electron microscopy examination of Ta2N films grown on BaF2(111) using the same deposition conditions showed that the average grain size was ≂10 nm. The room-temperature resistivity and temperature coefficient of resistivity of films grown on glass were 2×10−4 Ω cm and 1.2×10−4 K−1, respectively. The films exhibited relatively low compressive stresses, 1–3×109 dyn cm−2, and film/substrate couples photolithographically patterned into thin-film heater elements withstood 2×107 thermal cycles between <200 and ≂850 °C.