Properties of amorphous aluminate dielectrics synthesized via photosensitized pulsed laser ablation of luminescent targets

The dielectric properties of (Ce,Tb)MgAl₁₁O_x films deposited by pulsed laser deposition are reported. The optical absorption from the rare earth dopant in the polycrystalline target material serves as an efficient photosensitizer for laser ablation when a laser source operating in the ultraviolet is employed. The deposited films are amorphous with few, if any, particulates evident on the surface. Metal-insulator-metal device structures were fabricated using these films, measuring the dielectric and leakage current properties. The relative dielectric constant of the amorphous aluminate is on the order of 10. Leakage currents as low as 6 × 10^{- 8} A/cm ² at an applied field of 0.6 MV/cm were realized.