Effect of Flow Conditions on Nanoparticle Aerosol Deposition for Direct Writing Purposes

Abstract

Nanoparticles have unique properties that are sought after for the development and improvement of applications. Prerequisite to achieve these applications, methods are required to put the nanoparticles in different patterns and arrangement on a target substrate.
In the course of developing an aerosol-based nanoparticle printing system, this work explores the results of different aerosol deposition configurations.
The work is based on a spark ablation process that generates an aerosol of argon and copper nanoparticle agglomerates. The deposition configuration deposits the aerosol on a target substrate. Three configurations are explored, one which deposits at subsonic velocities, and two which deposit at sonic velocities. The aim is to find the most favourable deposition conditions for the direct writing of nanoparticle patterns.
It is found that a sonic deposition configuration with a low pressure ratio at small substrate distances has the smallest deposit diameter. The configuration allows for the patterning of narrow lines, that consist of two deposition regions: a micro-aggregate region and a nanoparticle region. It was found that the density of these regions is mainly influenced by the process variables of the spark ablation process, and can thus be used to gain a high consistency and well-defined edges.