%0 Journal Article
%T TEMPLATE-ASSISTED FABRICATION AND DIELECTROPHORETIC MANIPULATION OF PZT MICROTUBES
%A VLADIM¨ªR KOVA£¿
%J Ceramics-Silik¨¢ty
%D 2012
%I Academy of Sciences of the Czech Republic
%X Mesoscopic high aspect ratio ferroelectric tube structures of a diverse range of compositions with tailored physical properties can be used as key components in miniaturized flexible electronics, nano- and micro-electro-mechanical systems, nonvolatile FeRAM memories, and tunable photonic applications. They are usually produced through advanced ¡°bottom-up¡± or ¡°topdown¡± fabrication techniques. In this study, a template wetting approach is employed for fabrication of Pb(Zr0.52Ti0.48)O3 (PZT) microtubes. The method is based on repeated infiltration of precursor solution into macroporous silicon (Si) templates at a sub-atmospheric pressure. Prior to crystallization at 750¡ãC, free-standing tubes of a 2-¦Ìm outer diameter, extending to over 30 ¦Ìm in length were released from the Si template using a selective isotropic-pulsed XeF2 reactive ion etching. To facilitate rapid electrical characterization and enable future integration process, directed positioning and aligning of the PZT tubes was performed by dielectrophoresis. The electric field-assisted technique involves an alternating electric voltage that is applied through pre-patterned microelectrodes to a colloidal suspension of PZT tubes dispersed in isopropyl alcohol. The most efficient biasing for the assembly of tubes across the electrode gap of 12 ¦Ìm was a square wave signal of 5 Vrms and 10 Hz. By varying the applied frequency in between 1 and 10 Hz, an enhancement in tube alignment was obtained.
%K PZT
%K Microtubes
%K Vacuum infiltration
%K Dielectrophoresis
%U http://www.ceramics-silikaty.cz/2012/pdf/2012_03_177.pdf