Copper electrodeposition using a novel Type IV deep eutectic solvent

The research aimed to develop a new deep eutectic solvent (DES) composed of a mixture of lithium chloride and 1,3-propanediol, mixed at a 1:4 molar ratio, and used it for testing of electroplating of copper. Structural and electrochemical properties of copper electrolytes were determined with and without the use of the additives by using various electrochemical techniques, including cyclic voltammetric (CVs) measurements. Physical properties of the additive-free and additive-dispensed propanediol-based DES, such as electrical conductivity, were determined. The intent of this analysis was to determine how the additives present in the solvent altered the dissolving properties of the solvent, thus changing the electroplating process. The research further extends the knowledge of the newly introduced DES with respect to its impact on copper electrodeposition on nickel substrates. This evaluation was undertaken both with and without additives in order to assess their impact on the electroplating process. Important properties of the deposited copper, including thickness, surface shape, and surface roughness, were measured and compared. Finally, more sophisticated methods have been used to gain a deeper understanding of the copper deposits. The surface morphology of the deposits was analyzed by field emission-scanning electron microscopy (FESEM), and atomic force microscopy (AFM) was particularly useful in ascertaining the surface roughness. These methods enabled the observation and measurement of the microstructural variances of the copper deposits produced in different experimental setups.