We have observed a novel modification of a surface state due to a local strain field induced by a nanopattern formation. N adsorption on the Cu(100) surface induces a nanoscale grid pattern, where the clean Cu regions remain periodically. The lattice is contracted on the clean region by adjacent c(2 x 2)N domains, which have a larger lattice constant. On this patterned surface, we have investig...

MOLECULAR CRYSTALLIZATION DIRECTED BY NANOPARTICLESAND NANOPATTERNS byLI LIAugust 2013Advisor: Dr. Guangzhao MaoMajor: Materials Science and EngineeringDegree: Doctor of PhilosophyThis dissertation focuses on nanoparticle/nanopattern-induced molecularself-assembly and crystallization. We propose a universal strategy to synthesizeorganic/inorganic hybrid n...

The ability to assemble discrete nanowires (NWs) with nanoscale precision on a substrate is the key to their integration into circuits and other functional systems. We demonstrate a bottom-up approach for massively parallel deterministic assembly of discrete NWs based on surface-guided horizontal growth from nanopatterned catalyst. The guided growth and the catalyst nanopattern define the direc...

We present a review of the theoretical and experimental evidence for the peculiar properties of comb copolymers, demonstrating the uniqueness of these materials among other polymer architectures. These special properties include an increase in stiffness upon increasing side-chain length, the spontaneous curvature of adsorbed combs, rod-globule transition, and specific intramolecular self-assemb...

Conventional atomic force microscope nanomanipulation is inefficient because of the serial imaging/manipulation operation. We present here a parallel imaging/manipulation force microscope PIMM to improve manipulation efficiency. The PIMM is equipped with two individually actuated cantilevers with protrudent tips. One cantilever acts as an imaging sensor by scanning nano-objects and tip of the o...

In this report, ordered lead zirconate titanate Pb(Zr0.52Ti0.48)O3 (PZT) nanodot arrays were fabricated by an original one-step mask etching route. The one-step mask etching strategy is based on the patterned nanostructure of barrier layer (BL) at the bottom of anodic aluminum oxide (AAO), by a direct transfer of the nanopattern from BL to the pre-deposited PZT film, without introduction of any...

Enhanced light extraction from a GaN-based power chip (PC) of green light-emitting diodes (LEDs) with a rough p-GaN surface using nanoimprint lithography is presented. At a driving current of 350 mA and with a chip size of 1 mm × 1 mm packaged on transistor outline (TO)-cans, the light output power of the green PC LEDs with nano-rough p-GaN surface is enhanced by 48% when compared with the same...

Using poly(5-{[(4'-heptoxy-4-biphenylyl)carbonyl]oxy}-1-pentyne) as an example, we demonstrate the incorporative accommodation of the rigid polyacetylene backbones and the mesogenic pendants, which leads to a highly ordered smectic (Sm) phase with a frustrated structure. The polymer exhibits a recognizable sheetlike molecular shape due to its rigid backbone and relatively short spacer (three me...

We have studied the mechanism of nanopattern formation by self-assembly of impurities aggregated on the Fe3O4s001d surface. Self-assembly was controlled by thermal diffusion from the bulk of natural and artificial single crystals. We show that the diffusion of potassium and calcium is of fundamental importance to the surface dynamics of magnetite. The self-assembly of Ca and K impurities, combi...