Improvement of ferroelectric properties through the control of interfacial quality in sol-gel derived lead zirconate titanate thin film

Ferroelectric lead zirconate titanate (PZT) thin films have been investigated for a variety of applications such as piezoelectric, pyroelectric, electro-optic and ferroelectric devices. However, the degradation of ferroelectric properties induced by inter-diffusion or poor crystalline quality at the film-substrate interface leaves a problem to be solved still now. Many authors have tried to resolve these obstacles by using buffer layers or seed layers for low temperature process. Especially, sol-gel method is so attractive for its uniform control of composition and ease of layer-by-layer deposition. In this work, ultrathin PZT layer containing various contents of excess Pb was used as an interfacial layer to investigate the role of excess Pb on the formation of interfacial region between PZT film and Pt bottom electrode.