Dielectric characteristics of nanocrystalline Ag-Ba0.5Sr0.5TiO3 composite thin films

Abstract

Nanocrystalline Ag-Ba0.5Sr0.5TiO3 (Ag-BST) composite thin films are deposited on Pt/Ti/SiO2/Si substrates by a sol-gel method. The voltage-dependent capacitance (C-V) and dielectric loss of the films decrease with increasing Ag up to 2 mol % due to a series configuration involving low dielectric interface layers and dense microstructures. The evidence for asymmetric distribution of charge carriers in the Ag-BST film is derived from C-V measurements. The dielectric tunability of BST film with 1 mol % Ag is comparable to that of pure BST. (C) 2004 American Institute of Physics.