Hydrothermal Synthesis of Nano-sized PbTiO3 Powder and Epitaxial Film for Memory Capacitor Application

Hydrothermal synthesized lead titanate powder was prepared in a Teflon-lined stainless steel bomb. Calcium fluoride (CaF2) and titanium dioxide (TiO2) were separately adapted as intermediate layers on p-Si (100) substrates. The microstructures of TiO2 and CaF2 layers were examined by FESEM. Lead titanate (PbTiO3) film was formed on both the CaF2/Si and TiO2/Si structures using the spin coating technique. FESEM images revealed the nano-sized grain morphology of PbTiO3 films. C-V characteristics were measured and good hysteresis nature was formed for both MFIS structure of the film. The Sawyer-Tower circuit was also used to look at the P-E hysteresis loop of both MFIS cells. The loop of PT/TiO2/Si was wider than that of PT/CaF2/Si cell. Also, the higher value of polarization (Ps=49.2 µC/cm2) for PT/TiO2/Si could be explained on the basis of higher dipole moment in this TiO2 buffer layer.