DEPOSITION OF TANTALUM OXIDE-FILMS BY UV LASER REACTIVE ABLATION IN O-3 AMBIENT

Tantalum oxide films, have been deposited on n-type silicon substrate by 355 nm laser ablation of Ta2O5 in the presence of O-3. The dielectr ic and electrical properties of Ta2O5 films after annealing treatment have been studied. The results suggest that the film has dielectric co nstant of 28, and leakage current of 10(-7) A/cm(2) at an applied elec tric field of 500 kV/cm. The capacitance-voltage characteristics of th e Al/Ta2O5/n(+)Si capacitors exhibit an interface trap density and bor der trap density of 3 x 10(11) eV(-1) cm(-2) and 1.2 x 10(11) cm(-2), respectively The effect of ambient gases during laser deposition on th e border trap densities of annealed films are also discussed.