FABRICATION OF FERROELECTRIC BI4TI3O12 THIN-FILMS BY DIPPING-PYROLYSIS OF METAL NAPHTHENATES AND MICROPATTERNS BY AN ELECTRON-BEAM

Fabrication of ferroelectric Bi4Ti3O12 thin films was carried out by dipping pyrolysis of metal naphthenates. Single-phase Bi4Ti3O12 thin films with c-axis orientation perpendicular to the substrate surface were fabricated on Pt plates. They exhibited good ferroelectric properties: coercive held of 7.7 kV/cm and remanent polarization of 8.2 mu C/cm(2). For the films fabricated on Pt/Ti/SiO2/Si substrates, however, the Bi2Ti2O7 phase mainly grew because of Ti diffusion into the bismuth titanate layer during the heat treatment. Fine micropatterns with linewidth of less than 1 mu m in precursors of Bi4Ti3O12 were formed by spin-coating, irradiation with an electron beam and development. They were crystallized into the Bi4Ti3O12 phase by successive pyrolysis and annealing. The reaction between the metal naphthenate films and energized electrons was studied by IR spectroscopic analysis.