To establish a new Si-electrodeposition process, the optimum conditions for obtaining adherent, compact, and smooth Si films using molten KF-KCl-K2SiF6 were investigated at 923 K. Galvanostatic electrolysis was conducted on a Ag substrate in eutectic KF-KCl (45:55 mol%) with various current densities (10-500 mA cm(-2)) and K2SiF6 concentrations (0.5-5.0 mol%). Cross-sectional scanning electron microscopy (SEM) of the deposits revealed that compact and smooth Si films form at intermediate K2SiF6 concentrations and current densities. The relationship between the deposition conditions and Si morphology is discussed in terms of the electrodeposition mechanism. (C) 2015 The Electrochemical Society. All rights reserved.