Oscillatory Behavior in Electrochemical Deposition Reaction of Polycrystalline Silicon Thin Films through Reduction of Silicon Tetrachloride in a Molten Salt Electrolyte

A new electrochemical oscillation is found for reduction reaction of silicon tetrachloride on a partially immersed single crystal n-Si electrode in a lithium chloride-potassium chloride eutectic melt electrolyte. The reduction of SiCl4, which is almost insoluble in the electrolyte, occurs mainly near the upper edge of an electrolyte meniscus on the electrode, and it is discussed that the oscillation is caused by a change in the height of the meniscus due to a change in the chemical structure (and hence the interfacial tension) of the electrode surface with progress of the silicon deposition reaction.