Automated on-line optimization of an epitaxial process

As part of a system for process control, the run by run controller implements a form of adaptive control based on the sequential design of experiments. The run by run controller can be applied to the local optimization, feedback control, and feedforward control or processes in which multiple inputs control multiple output characteristics. Current work concerns the application of the controller to the optimization and control of thickness and resistivity uniformity of silicon epitaxy. Initial experiments to investigate the effect of noise and disturbances on an AME 7800 barrel reactor indicate that the system is a good candidate for modeling and control using the multiple response surface method, wherein each measured site is separately modeled with a response surface and the uniformity metric is calculated from these models