Self-Organization of Colloidal Nanoparticles Into Functional Pressure Sensing Device

In this work, we report the multilayer thin film device for pressure sensing based on self-organized colloidal nanoparticles through the Layer-by-Layer (LbL) technique. The method in which macromolecules and nanoparticles are self-organized into assemblies to create novel nanostructures is receiving increasing research attention. Nanoparticles based multilayer thin films through the LbL self assembly process relies on electrostatic interaction of charged nanoparticles on flat substrates are reported as an interesting alternative for the fabrication of electronic devices.(3) These electronic devices composed of alternating chitosan capped zinc sulphide nanoparticles layers and citrate stabilized gold nanoparticles layers onto ITO coated glass substrates. The multilayered assemblies, attached to the surface by strong ionic bonds, were highly stable and could not be removed by moderate scratching. The multilayer films can be applied to detect pressure with satisfactory results where the conduction onset voltage decreases linearly with the applied pressure. Current voltage (I-V) characteristics were measured at room temperature in direct current mode in samples grown with varying number of deposition cycles, which are directly related to the number of multilayers grown on the substrate. It is a promising method for the future of pressure sensing device fabrication.