Gold nanoparticle growth control - implementing novel wet chemistry method on silicon substrate

Abstract

Controlling particle size, shape, nucleation, and selfassembly on surfaces are some of the main challenges facing electronic device fabrication. In this work, growth of gold nanoparticles over a wide range of sizes was investigated by using a novel wet chemical method, where potassium iodide is used as the reducing solution and gold chloride as the metal precursor, on silicon substrates. Four parameters were studied: soaking time, solution temperature, concentration of the solution of gold chloride, and surface pre-treatment of the substrate. Synthesized nanoparticles were then characterized using scanning electron microscopy (SEM). The precise control of the location and order of the grown gold overlayer was achieved by using focused ion beam (FIB) patterning of a silicon surface, pre-treated with potassium iodide. By varying the soaking time and temperature, different particle sizes and shapes were obtained. Flat geometrical shapes and spherical shapes were observed. We believe, that the method described in this work is potentially a straightforward and efficient way to fabricate gold contacts for microelectronics.

On the role of metal particle size and surface coverage for photo-catalytic hydrogen production: A case study of the Au/CdS system

“…Au loading was performed using a novel and facile iodide reduction method [62]. Briefly, an aqueous solution of KI (15 mL, 5 mM, Sigma-Aldrich, ≥99.5%) was added to 0.1 g of CdS powder.…”

Effective approaches to improve Au etching process performance in MEMS devices

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