Every year the Nano Ontario conference features work from leading researchers through posters and oral presentations. The most exciting of this work is always the student poster presentations which cover a wide range of topics.
The organizing committee of the Nano Ontario conference each year decides on a way to rank the posters and awards prizes generously donated from our sponsors.
With the opening of abstract submission for the Nano Ontario 2014 conference in Windsor, we it's time to look back on the best posters of 2013 and inspire our researchers to present their best ideas at the upcoming conference.
The poster winners for the 2013 year were selected by the popular vote of the attendees to the conference by an anonymous ballot.
Without further ado, here are the winners of the 2013 poster prizes, a biography about each student:
Sandra J. Gibson M.Sc.
Sandra Gibson is currently a Ph.D. student at the Centre for Emerging Device Technologies at McMaster University in Hamilton, Ontario. Her first experience with nanotechnology began while she was pursuing her Bachelors Degree with Honors in Physics at Acadia University in Wolfville, Nova Scotia. There she worked with Dr. Michael Robertson at the Acadia Centre for Microstructural Analysis on several summer projects involving the characterization of various semiconductor nanostructures, such as porous silicon and III-V nanowires, using cathodoluminessnce spectroscopy. Upon graduation she then went on to complete a Masters degree at Laurentian University in Sudbury, Ontario under the supervision of Dr. Gennady Chitov. There she performed numerical studies of unconventional quantum phase transitions in strongly interacting low-dimensional quantum spin systems using the high performance computing resources of SHARCNET. She is now working with Dr. Ray Lapierre on the self-catalyzed growth of III-V nanowires by molecular beam epitaxy. During her work she has used the nanolithography facilities at the Emerging Communications Technologies Institute at the University of Toronto to prepare unique nano-patterned silicon substrates for the ordered growth of GaAs nanowire arrays. Her work has various applications for electronics and optoelectronics, for example use in future high efficiency multi-junction solar cell designs.
Abstract: Opportunities and pitfalls in patterned self-catalyzed nanowire growth on silicon
Our work is focused on the growth of patterned self-catalyzed GaAs nanowire arrays on silicon substrates by gas source molecular beam epitaxy (MBE), which is expected to make an excellent candidate material for high-efficiency photovoltaic applications. Patterning is required to produce the controlled nanowire morphology, uniformity and areal densities necessary for optimal ensemble nanowire devices. Using electron beam lithography, a template of nanoscale holes can be defined in a thin (100-300 Å) oxide layer, facilitating the growth of positioned nanowires while avoiding accompanying parasitic film deposition. Our experimental results show that the axial and lateral growth rates increase strongly with increasing the inter-hole spacing. We account for this by proposing that a significant proportion of growth material is supplied by a secondary flux of adatoms desorbing from the oxide surface between the nanowires. Shadowing of this flux by neighboring nanowires in the array may have a strong effect on the resulting growth.
Hamed Shahsavan M.A.Sc.
Hamed Shahsavan is a PhD student in the Surface Science and Bionanomaterials Laboratory at the University of Waterloo. He obtained his MASc in Chemical Engineering (nanotechnology) in 2011 from the University of Waterloo and his BSc in Chemical Engineering in 2009 from Sharif University of Technology. His research interests include fabrication and synthesis of "smart" surfaces and interfaces, bio-inspired topographical and chemical modification of polymeric surfaces, contact mechanics (adhesion, friction, and wetting) studies of synthetic smart biomimetic surfaces, and interfacial phenomena at nanoscales.
Abstract: Biomimetic Micro/Nano Structured Surfaces: Fabrication, Characterization, and Applications
Outstanding interfacial properties of the natural and biological systems have inspired the scientists to mimic these properties in the synthetic structures. Adhesive toe pads of gecko and superhydrophobic leaves of lotus plant are the most renowned examples of such systems. Herein, we report our recent progress in fabrication and characterization of synthetic biomimetic structures. Gecko-inspired fibrillar interfaces were fabricated and used to tailor adhesion, friction and wetting. Moreover, the leaves of trembling aspen plant were used for fabrication of synthetic random structures for the same purpose.
Tim Sipkens a MASc candidate at the University of Waterloo. His research has focussed on developing time-resolved laser-induced incandescence (TiRe-LII) into a diagnostic that can be applied to aid in nanoparticle synthesis and characterization. He has received several awards for his work including two Waterloo Nanofellowships, a NSERC CGS M, an Ontario Graduate Scholarship, an Arthur F. Church Scholarship, and an Iron Ring Graduate Scholarship. He has also prepared three award winning posters presented at nanotechnology and chemical engineering conferences. The associated work was subsequently published in Applied Physics B and the Journal of Heat Transfer. He was also awarded one of 16 positions in the competitive Nano Summer Program at the Center for Nanointegration Duisburg (CENIDE) in Germany. This led to a collaborative work that has been
published in Applied Physics B. Additional work with robust Bayesian analysis, as it applies to Reynolds-averaged Navier–Stokes (RANS) combustion modelling, has been submitted to Combustion Theory and Modelling.
Abstract: Inferring the Thermal Accomodation Coefficent from Time-Resolved Laser-Induced Incandesence on Iron Nanoparticles
Synthetic nanoparticles have emerging roles in diverse areas of science and engineering, including medicine, optics, and computer hardware. Since nanoparticle functionality is strongly size-dependant, there is a pressing need for an instrument that can size aerosolized synthetic nanoparticles. Time-resolved laser-induced incandescence (TiRe-LII), a combustion diagnostic used to measure soot primary particles, is being considered as a candidate for measuring synthetic nanoparticles. In this process, a sample of aerosol is energized using a laser pulse, and the spectral incandescence of the nanoparticles is measured as they re-equilibrate with the surrounding gas. Since larger nanoparticles cool more slowly than smaller ones, the data contains information about the size distribution. This poster describes TiRe-LII measurements on iron nanoparticles in helium, argon, nitrogen, and carbon dioxide. The nanoparticles were aerosolized from a prepared solution of iron monomers, which, for the first time, gives TiRe-LII practitioners control of the synthetic nanoparticle size independent of aerosol formation. Nanoparticle size and thermal accommodation coefficient (TAC), which defines the energy transfer when gas molecules scatter from the laser-energized nanoparticles, are found by Bayesian inference. Inferred TiRe-LII nanoparticle sizes are compared to those found by electron microscopy and dynamic light scattering. The inferred TACs are compared to values derived through molecular dynamics. The results highlight how the TAC changes with the buffer gas.