Conductive thin film multilayers of gold on glass formed by self-assembly of multiple size gold nanoparticles

Highly conductive thin films of gold have been fabricated on glass substrates by the deposition of gold nanoparticles of two different diameters. A deposition sequence, alternating between 2.6-nm and 12-nm diameter particles, was used whereby the 2.6-nm particles served to fill in the gaps created by the assembly of the larger 12-nm diameter particles. The resulting thin films, with thicknesses of less than 35 nm, displayed high conductivities, yet were fabricated in substantially fewer deposition cycles than required by previous methods. Analysis of surface morphology performed by atomic force microscopy and scanning electron microscopy showed that the high conductivity is the result of a less porous surface structure than can be achieved through the layering of a single size nanoparticle. Conductivity analysis was performed by 4-point probe with resistivities of 5.00 ± 0.4 x 10-6 Ω m for 5 layers and 4.49 ± 0.2 x 10-6 Ω m for the 6-layer films.