4. A scrubber is used to remove particles from a wafer surface in semiconductor processing. An engineer would like to determine the most important variables that optimize the scrubber's ability

to remove particles. There are 8 factors that can be manipulated. The engineer does not want to spend too much time doing this experiment. Given the following data: (a) Generate the most effective screening experiment. (b) What is the defining relationship? (c) Are any of your important interactions aliased with any main effects? (d) What is the resolution of your design?