A method of tuning a patterning stack, the method including: defining a function that measures how a parameter representing a physical characteristic pertaining to a pattern transferred into a patterning stack on a substrate is affected by change in a patterning stack variable, the patterning stack variable representing a physical characteristic of a material layer of the patterning stack; varying, by a hardware computer system, the patterning stack variable and evaluating, by the hardware computer system, the function with respect to the varied patterning stack variable, until a termination condition is satisfied; and outputting a value of the patterning stack variable when the termination condition is satisfied.