World Scientific Publishing, Functional Materials Letters, 01(06), p. 1250051
DOI: 10.1142/s1793604712500518
Full text: Download
Titanium thin films were deposited by DC magnetron sputtering. The glancing angle deposition (GLAD) method was implemented to prepare two series of titanium films: perpendicular and oriented columnar structures. The first series was obtained with a conventional incident angle α of the sputtered particles (α = 0°), whereas the second one used a grazing incident angle α = 85°. Afterwards, the films were annealed in air using six cycles of temperature ranging from 293 K to 773 K. DC electrical conductivity was measured during the annealing treatment. Films deposited by conventional sputtering (α = 0°) kept a typical metallic-like behavior versus temperature (σ300 K = 2.0 × 106 S m-1 and TCR293 K = 1.52 × 10-3 K-1), whereas those sputtered with α = 85° showed a gradual transition from metal to dielectric. Such a transition was mainly attributed to the high porous structure, which favors the oxidation of titanium films to tend to the TiO2 compound.