Preparation of Zr-Rich Pb(Zr,Ti)O 3 Films by Sol-Gel Technique

Abstract

Zr-rich lead zirconate titanate [Pb(Zr x Ti 1 m x )O 3 (PZT)] ( x =0.9) films were fabricated by sol-gel technique, using lead (II) acetate trihydrate, zirconium (IV) propoxide, and titanium tetraisopropoxide as source materials. Final heat treatment of rapid thermal annealing was done at 735°C for 4 min. PZT films fabricated directly on Ir/SiO 2 /Si substrate had a large grain size of 10-20 w m and bad electric properties, derived by the lack of adhesion. To arrange the adhesion of Ir surface, thin Ti film (∼1 nm) was introduced to Ir surface as a buffer layer. Employing the Ti layer, PZT grain size decreased to less than 1 w m. From the temperature dependence of dielectric constant, Curie temperature was 260°C and dielectric constant at 26°C was 750. Symmetric D - E hysteresis loop was observed, and remanent polarization and coercive field were 20 w C/cm 2 and 65 kV/cm, respectively. Zr-rich PZT film derived from sol-gel technique is expected to apply to ferroelectric memory and pyroelectric devices.