Applied Surface Science, Vol.253, No.12, 5293-5301, 2007
Direct micropatterning of high dielectric BaTiO3 films by laser-induced pyrolysis with a nano-crystalline seeding technique
A direct patterning method of dielectric BaTiO3 (BT) films is proposed, which applies laser-induced pyrolysis in combination with nanocrystalline seeding technique. A precursor solution of a BT complex alkoxide containing BT nano-crystal line particles with polyvinylpyrollidone (PVP) as dispersion stabilizer was spin-coated on Pt substrate. An Ar+ laser beam was focused and scanned on spin-coated BT films, which induced pyrolysis and crystallization of the films with spatial selectivity. Micropatterns were obtained by striping laser-unirradiated regions on the films with HCl aqueous solution. Raman spectra of the micropattern confirmed that the structures were tetragonal crystalline BT. Clear micropatterns with a line width of ca. 3 mu m and an interval of 5 mu m were formed at PVP concentrations of 25 and 50 kg/m(3). The dielectric constant and dissipation factor of the film fabricated at a laser energy density of 27 MW/cm(2) and a scanning speed of 25 mu m/s attained 76.2 and 0.07, respectively, for a measurement frequency of 100 kHz. (c) 2006 Elsevier B.V. All rights reserved.
Keywords:micropattern;laser-induced pyrolysis;BaTiO3;crystallization;dielectric properties;Raman spectroscopy