Effect of annealing on the dielectric permittivity of strontium titanate films in the SrTiO3/Al2O3 structure

Abstract

The paper reports an experimental study of the structure of a strontium titanate film on a sapphire substrate and of the dielectric properties of capacitors based on a SrTiO3 /Pt/Al2O3 multilayer system before and after a high-temperature anneal. The macro- and microstructure of SrTiO3 films and its variation induced by the annealing have been investigated. The temperature and field dependences of the dielectric permittivity of strontium titanate films have been determined, and their comparison with similar data for single crystals carried out. The mechanisms by which annealing can affect the capacitor capacitance and the properties of SrTiO3 films are discussed. © 1998 American Institute of Physics. [S1063-7834(98)01608-6].