Effect of laser fluence on the microstructure and dielectric properties of pulsed laser-deposited CaCu_3Ti_4O_(12) thin films

摘要

Polycrystalline CaCu_3Ti_4O_(12) (CCTO) films were grown on Pt/Ti/SiO_2/Si substrates using pulsed laser deposition. The choice of optimal laser fluence was found to be important to the microstructure and dielectric properties of CCTO films. Thin films with a (220) preferential orientation were obtained in a narrow fluence range of 1.8-2.0 J/cm~2. Moreover, the CCTO films deposited at 2.0 J/cm~2 showed high dielectric constant (2474) and low dielectric loss (0.05) at 10 kHz, which was ascribed to the improved crystallinity.