Epitaxial growth of dielectric CaCu3Ti4O12 thin films on (001) LaAlO3 by pulsed laser deposition

Abstract

High dielectric ${\mathrm{CaCu}}_3{\mathrm{Ti}}_4{\mathrm{O}}_{12}$ (CCTO) thin films were epitaxially grown on (001) ${\mathrm{LaAlO}}_3$ (LAO) substrates by pulsed laser deposition. Microstructural studies by x-ray diffraction, pole figure measurements, and transmission electron microscopy show that the as-grown films are good single crystalline quality with an interface relationship of ${\text{(001)}}_{\mathrm{CCTO}}{\text{//(001)}}_{\mathrm{LAO}}$ and ${\text{[100]}}_{\mathrm{CCTO}}{\text{//[100]}}_{\mathrm{LAO}}.$ Dielectric property measurements show that the films have an extremely high dielectric constant with value of 10 000 at 1 MHz at room temperature. It is interesting to note that the twinned substrate results in the formation of twinning or dislocations inside the CCTO film.