Electrodeposition of amorphous silicon at room temperature on flexible substrates

In this work, we report a facile method for the low-cost electrodeposition of amorphous silicon on conductive substrates, at room temperature. We carried out the deposition in an aprotic solvent, propylene carbonate. The electrolyte solution contains silicon precursor (silicon tetrachloride) and a supporting electrolyte to enhance the conductivity of the solution. An inert atmosphere is required to prevent any hydrogen evolution as well as evaporation of the precursors. A black coloured silicon layer appeared on the substrate due to the reduction of the precursor. The resulting coating was characterized using XRD, EDX, SEM, Raman spectroscopy, and stylus surface profiler. The EDX results illustrated the presence of elemental silicon in the film, along with some traces of silicon dioxide. XRD exhibits an Si peak at two theta 28.3° confirming the presence of silicon in the film. The broad hump depicts the amorphous nature of the deposited silicon film in the XRD scan at lower angles as well as by the broad spectra obtained in Raman spectroscopy. The process developed represents a low cost, non-energy intensive, and a scalable approach for amorphous silicon deposition on traditional and flexible conductive substrates.