Fabrication of high aspect ratio ferroelectric microtubes by vacuum infiltration using macroporous silicon templates

Article abstract of DOI:10.1111/j.1551-2916.2006.01123.x

Ordered arrays of high aspect ratio (>10:1) ferroelectric Pb(Zr _0.52Ti_0.48)O₃ (PZT) tube structures were fabricated by vacuum infiltration of macroporous silicon (Si) templates. Improved phase purity was achieved when PZT microtubes were pyrolyzed at 300°C and partially released from the Si template to prevent a chemical reaction between the Pb and the Si during subsequent high-temperature crystallization. The free-standing microtubes were crystallized by rapid thermal annealing at 750°C for 1-3 min. Perovskite phase formation was confirmed by X-ray diffraction and transmission electron microscopy methods. Coaxial structures comprised of metallic LaNiO₃, PZT, and Pd layers were also processed to enable future electrical characterization of the ferroelectric microtubes.