Conductor microstructures by laser curing of printed gold nanoparticle ink

Abstract

The laser-based curing of printed nanoparticle ink to create microlines (resistors) of electrical resistivity approaching that of bulk gold was investigated. The present work relies on laser absorption in both the nanoparticle ink and the sintered gold layer, as well as the transport of thermal energy in the substrate and the resulting solvent vaporization and nanoparticle deposition and sintering. The morphology and electrical properties of the gold line can be controlled by modulating the spatial distribution of the laser beam intensity. Based on the understanding of the underlying physics, a process that circumvents a serious drawback on the functionality of cured gold microlines is produced. Microconductors with resistivity approaching that of bulk gold are produced, while loss of gold nanoparticles and cross sectional nonuniformities are avoided.