NM05.11.09 : ZnSnO3 Nanowires as a Lead-Free Alternative for Piezotronics Devices Constructed Using a Template-Based Growth

5:00 PM–7:00 PM Apr 5, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E

Domingo Mateo-Feliciano1 Aayat Sabah1 Fouad Albadrasawi1 Pritish Mukhrjee1 Sarath Witanachchi1

1, University of South Florida, Tampa, Florida, United States

Lead-free ferroelectric materials with functionalities similar to lead zirconium titanate oxide (PZT) are of great interest in multitudes of technologies. PZT is considered the standard material for ferroelectric, piezoelectric and piezotronics applications but due to lead toxicity, the development of lead free piezoelectric materials with earth abundant elements has gained considerable attention in the ferroelectric community. Ferroelectric hysteresis behavior with high remnant polarization has been reported from LiNbO3 -type (LN-type) Zinc Stannate (ZnSnO3) hybrid nanoparticle-nanowire (NP-NW) arrayed films. Our group has previously reported the growth of ZnSnO3 in nanowire form on conducting substrates. Optimization studies of growth for LiNbO3 -type (LN-type) Zinc Stannate (ZnSnO3) NWs were performed. These nanowires show considerable potential for ferroelectric and piezotronic applications yet, random nanowire growth causes problems for device miniaturization and nano-force measurements as these require the use of a very small number (or even an individual) of wires in substrates. To achieve this, a novel template based technique using spatially ordered Aluminium doped Zinc Oxide/250nm-Silica Nanospheres (Al:ZnO/250nm-SNS) template was used as initial seed layer. A self- assembled silica nano template is constructed using Langmuir-Blodgett dip coating technique and subsequently, z-axis oriented Al:ZnO NCs were grown on top of the monolayer template using the glancing angle pulsed laser deposition (GAPLD) technique. Previous work has explored the tunability of Al:ZnO NCs aspect ratios due to on underlying sphere size. These Al:ZnO NCs can serve as nucleation sites for ZnSnO3 NWs. After template construction, the ZnSnO3 NW’s were grown using a low temperature solvothermal process. A structural study of the ZnSnO3 NW’s arrays grown on the Al:ZnO/250nm-SNS template using X-ray diffraction spectrometry will be performed for different growth conditions to find a preferential growth orientation and crystallinity of NW arrays on the template. Preferential growth of (012) plane of standard LN-type ZnSnO3 is expected, as reported in literature. After structural studies and characterization of the ZnSnO3 NWs is completed, mechanical studies will be performed to determine the formation of depletion zones and the separation of charges due to mechanical stresses on the wires. Regions in between NWs will be filled with a conducting material and with the application of a constant voltage in a direction perpendicular to the wires, a mechanical stress on the wires will change the overall measured voltage on the device.