Fabrication of large-area ordered arrays of nanoparticles on patterned substrates

Abstract

Many potential applications in nanotechnology require virtually defect-free arrays of nanometre-scale particles over large areas. Guided self-assembly of colloidal particles on patterned templates has been shown to produce ordered arrays of colloidal particles. However, there is a need to extend this technique to particles measuring much less than 50 nm in size and to develop robust fabrication techniques that would lead to defect-free, large-area arrays. We have investigated the use of the dip-coating technique to assemble one- and zero-dimensional arrays on patterned templates using particles with diameters in the 15–50 nm range. Substrates with high-resolution groove or hole patterns were prepared with extreme-ultraviolet interference lithography (EUV-IL). Particle arrays with low defect density were achieved by adapting the deposition conditions (particle concentration, pH, dip speed and orientation). The experimental findings are explained with a model that describes the relative influences of the contributing forces in the assembly process. The driving force behind the assembly is found to be the capillary forces that organize the particles with respect to the pattern on the substrate and each other. The process does not seem to impose any inherent limitations on the defect density or the size of the particle arrays.

Simulation Methodology for Synthesis of Antenna Substrates With Microscale Inclusions

“…For example, conventional patch antennas are made using destructive processes where a copper layer covers the entire surface and then environmentally damaging chemicals are used to etch away the unwanted sections. By using additive manufacturing processes such as electrodeposition and selfassembly [3][4][5] complete antenna structures and associated RF components including the feed and the balun can be  Manuscript received July 7, 2011. This work was supported by EPSRC under Grant No.…”

Microwave antennas and heterogeneous substrates using nanomaterial fabrication techniques

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Microstrip patch antennas on substrates with metallic inclusions

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