Fabrication of Tetragonal Pb(Zr,Ti)O₃Nanorods by Focused Ion Beam and Characterization of the Domain Structure

Abstract

It has been widely revealed and discussed that the properties of ferroelectric nanostructures vary with their dimensionality and size. The mechanical substrate clamping and the depolarization field are considered as major factors, which cause their unique properties. In this paper, we fabricated tetragonal {100}-Pb(Zr, Ti)O3 rods with 100 nm - 4 μm widths on Nb-doped SrTiO3 substrates by using focused ion beam, and characterized their domain structure by synchrotron micro X-ray diffraction. It was found that the clapping angle in the a/c-domain structure became larger with decreasing the rod width, which indicates the significant reduction of substrate clamping by fabricating narrow rods.

Charge screening strategy for domain pattern control in nano-scale ferroelectric systems

“…Indeed, although we carefully etched the PZT with low acceleration voltages of ion beam, especially for finalizing the FIB process, a reduction of the piezo-response was observed due to the Ga injection and amorphousization at the vicinity of the surface. However, this was recovered by annealing the fabricated structure at the temperature ≥550 °C 30, 31 . Similar post-treatments have been also reported for recovering from the FIB damage in nanostructured ferroelectrics 32, 33 .…”

“…Rods of widths 200 nm, 500 nm, 1 μm, 2 μm, and 4 μm were fabricated (in this paper, the word “rod” is used for all the fabricated structures for simplicity, even when the aspect ratio is less than 1). The detailed structure was reported in refs 29, 30 and 31. For recovery from the etching damage and promotion of the formation of a stable domain structure, the PZT nanorods were annealed at 550–650 °C in air for 2 h.…”

Fabrication and characterization of (111)-epitaxial Pb(Zr0.35Ti0.65)O3/Pb(Zr0.65Ti0.35)O3 artificial superlattice thin films

“…[1][2][3] Although the required function (direct or converse piezoelectricity) and piezoelectric tensors are different for different applications, it has been clarified that there is a negative impact of substrate clamping on the converse piezoelectric response in ferroelectric thin films. [2][3][4][5] In particular, to improve the out-ofplane response, various approaches, such as orientation control [6][7][8][9] and the fabrication of large aspect-ratio nanostructures, [10][11][12][13][14][15][16] have been taken and, indeed, the response was successfully improved. These approaches basically reduce the substrate clamping or its influence on piezoelectricity; the former can be achieved by a specific multidomain structure, in which the polar distortion can be compensated between neighbor ferroelectric domains, or the small footprint of large aspect ratio nanostructures; the latter can be achieved by utilizing the anisotropic nature of the piezoelectric properties of ferroelectric materials.…”