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

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 2mol% 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 1mol% Ag is comparable to that of pure BST.