Multi-attribute optimization of diamond-like carbon thin films

Due to the numerous process parameters involved in the diamond-like carbon (DLC) thin film deposition process, it is practically impossible to find the optimum settings of the deposition process that would lead towards the most desired coating. The optimal parameter selection process gets further complicated when multiple objectives need to be satisfied-which are often in conflict with each other. Though the use of metaheuristics that leads towards Pareto frontier may be a viable solution, it is generally computationally intensive. Thus, in this paper, four different multi-criteria decision-making approaches (weighted sum model, weighted product model, weighted aggregated sum product assessment and technique for order preference by similarity to the ideal solution) are used to optimize the parameters involved in Zr-DLC deposition process. The bias voltage, Zirconium target current, pulse frequency, methane gas flow rate and work distance are selected as the controllable factors. Minimization of wear rate and maximization of deposition rate are the desired goals.