Spatially selective electrochemical deposition of composite films of metal and luminescent Si nanoparticles

We report on a procedure for selective deposition of Si nanoparticles using an electrochemical process. A conducting substrate is immersed in alcohol in which the particles are suspended. Biasing the substrate positively relative to a platinum electrode draws the Si particles to the substrate. Thin particle coatings on metal, foil, or silicon substrates are demonstrated. Fluorescent spectroscopy shows that the deposited particles retain the high luminescence efficiency and spectral distribution characteristic of the dispersed state. The process is used to deposit composite thin films of metal and Si nanoparticles. Dielectric masking allowed selective area deposition. These processes have implications for flat panel or flexible particle-based displays.