Synthesis and Characterization of PZT Ferroelectric Nanocrystals Current Measurement

Ferroelectric lead zirconium titanate (PZT) has been used in FeRAMs, which are expected to become common large capacity devices. We have extensively studied PZT thin films and their micro-processing. However, there are several problems of degradation by crystal defects at grain boundaries in thin films and surface damage by microfabrication. Self-assembled nanocrystals are useful for solving these problems. However, position control in nanocrystal growth is very difficult. Thus, atomically flat substrates and RF magnetron sputtering together are used for better position control. RF magnetron sputtering stimulates nucleation of crystals because the sputtered particles impinge on substrates with high energy. We grew PZT nanocrystals on alpha-Al₂O₃ (001) single crystalline substrate surfaces. Atomic force microscopy observations indicated that triangular-shaped crystals were formed on the substrates.