Synthesis Mechanisms of Organized Gold Nanoparticles: Influence of Annealing Temperature and Atmosphere

Abstract

We report on the synthesis of organized arrays of gold (Au) nanoparticles on thermally oxidized Si wafers using sputtering as a metal deposition method in combination with sphere lithography. This simple process leads to the formation of a honeycomb mask of Au at room temperature (RT). We study the transformation mechanism of this honeycomb mask to a hexagonal array of Au nanoparticles by annealing at different temperatures and in different atmospheres. The underlying mechanisms of pattern formation during annealing are coalescence of particles and Ostwald ripening and depend on temperature and atmosphere. The crystallinity and orientation of the nanoparticles with respect to the underlying substrate is analyzed by electron backscatter diffraction (EBSD), and the control of the morphology, size, shape, and orientation in different atmospheres (argon (Ar), nitrogen (N2), air, hydrogen (H2), and vacuum) is discussed.

Deflection induced cellular focal adhesion and anisotropic growth on vertically aligned silicon nanowires with differing elasticity

“…This ultimately leads to the formation of AuNPs. 23 After reaching the reaction temperature, vapor-phase Si precursors are introduced into the liquid-phase AuNPs by 10% H 2 in an Ar carrier gas, thereby forming a single crystal of Si by precipitation from the Au-Si alloy upon reaching supersaturation. 24 Finally, vertically aligned SiNWs are synthesized by vapor-liquid-solid growth from the AuNPs.…”

Annealing of Au, Ag and Au–Ag alloy nanoparticle arrays on GaAs (100) and (111)B

“…In addition, growth rate variations from NW to NW across the sample can be detrimental when fabricating heterostructured NWs since achieving reproducible/homogenous thicknesses of the shell/core and segments within the NWs becomes problematic. The extra level of control reached when being able to also pre-define the position the NWs, and at the same time control both the total and the local density for every NW across the sample, is made possible only when employing a lithography technique [17,27,28].…”

Adhesion Control for Micro- and Nanomanipulation

“…In recent years, various techniques, based on "nanosphere lithography", have been reported for nano/microfabrication or nano/micropatterning of a wide variety of solid substrates including metals, [44][45][46][47][48] semiconductors 49,50 and ceramics. 51 Recently, we reported structuring surface by nanospheres lithography and measured the adhesion force.…”