Dielectric Properties of (111) and (100) Lead-Zirconate-Titanate Films Prepared by Sol-Gel Technique

Dielectric properties of <111>- and <100>-preferred lead-zirconate-titanate (PZT) films with thickness of 400 nm prepared by the sol-gel deposition technique have been investigated from ferroelectric random-access memory (FRAM) and dynamic random-access memory (DRAM) application standpoints. Remanent polarization of <111>-preferred film is 23.5 µ C/cm2, which is somewhat higher than that of the <100>-preferred one. In contrast, the dielectric constant of <100>-preferred film is 730 which is larger than that of the <111>-preferred one. Thus, dielectric properties of PZT films are strongly dependent on their crystalline orientations. The <111>-preferred PZT film is appropriate for FRAM application and the <100>-preferred one is better for DRAM.