PREPARATION OF PBTIO3 THIN-FILMS USING AN ALKOXIDE-ALKANOLAMINE SOL-GEL SYSTEM

Abstract

The stable range of PbTiO3 sol and the processing conditions of uniform thin films were investigated using a solution of titanium isopropoxide, three kinds of alkanolamines (monoethanolamine, diethanolamine, triethanolamine), lead acetate trihydrate and isopropanol. Depending on the sol state with various alkanolamine/alkoxide molar ratios, diethanolamine (DEA) was very effective in preparing uniform and dense oxide films through room-temperature reaction, owing to its superior stability during the hydrolysis and condensation reaction. Perovskite PbTiO3 thin films were obtained on oxidized silicon wafer above 550 degrees C and completely pure films were obtained at 650 degrees C using DEA as a complexing agent. The dielectric constant and loss tangent of these thin films fired at 650 degrees C for 30 min were found to be similar to 240 and similar to 0.01 at 1 kHz, respectively.