Annealing temperature-dependent structural and electrical properties of (Ta2O5)1-x - (TiO2)x thin films, x ≤ 0.11

(Ta2O5)1-x- (TiO2)x (TTOx) thin films, with x = 0, 0.03, 0.06, 0.08, and 0.11, were deposited using magnetron direct current (DC) sputtering method onto the P/boron-silicon (1 0 0) substrates by varying areas of Tantalum and Titanium metallic targets, in oxygen environment at ambient temperature. The as-deposited thin films were annealed at temperatures ranging from 500 to 800 ?C. Generally, the formation of the Ta2O5 structure was observed from the X-ray diffraction measurements of the annealed films. The capacitance of prepared metal? oxide? semiconductor (MOS) structures of Ag/TTOx/p-Si was measured at 1 MHz. The dielectric constant of the deposited films was observed altering with varying composition and annealing temperature, showing the highest value 71, at 1 MHz, for the TTOx films, x = 0.06, annealed at 700 ?C. With increasing annealing temperature, from 700 to 800 ?C, the leakage current density was observed, generally decreasing, from 10-5 to 10-8 A cm-2, for the prepared compositions. Among the prepared compositions, films with x = 0.06, annealed at 800 ?C, having the observed value of dielectric constant 48, at 1 MHz; and the leakage current density 2.7 ? 10-8 A cm- 2, at the electric field of 3.5 ? 105 V cm-1, show preferred potential as a dielectric for high-density silicon memory devices.