The profile error feedback optimization for the design of a showerhead system controlling gas flow uniformity in a thin-film reactor

The design of a vector showerhead in a vertical reactor involves thousands of holes on the showerhead face plate and mass transport in the reactor, and the design variables and objective are always spatial related continuous characteristic, so the discretized sequence of the design variables has too many degrees of freedom that the needed sampling points of a design of experiment or heuristic algorithm methods are hardly acceptable. In order to solve this problem, a profile error feedback(PEF) optimization method was proposed. This method employed a loop-iteration-approximation mode, and started from a guessed initial model, and then fed back the profile error of design objective, according to a weight function, to continually adjusted the design variable sequence to make the gas flow uniformity in the new model continually approximate the perfect one. The optimization case of a vector showerhead system shown that the non-uniformity of the gas flow was reduced from 0.36% to 0.03% under a typical process condition.