Pulsed laser deposition of tantalum oxide thin films

High quality Ta2O5 films have been deposited on Si substrate by 532 nm pulsed laser deposition at O2 gas environment. X-ray diffraction measurement shows that the as-deposited films are amorphous, and a phase transformation to polycrystalline of β-Ta2O5 takes place after annealing the film at 800°C for 30 min. Physical and electrical measurements reveal that the polycrystalline Ta2O5 films have good properties: refractive indices ∼2.15, dielectric constants ∼35, and leakage currents <5×10−9 A/cm2 at an applied electric field of 100 kV/cm.