In this article, as in industry, advanced process control (APC) refers primarily to multi-variable control. Multivariable control means adjusting multiple single-loop controllers in unison, to meet ...

By measuring each wafer after lithography and adjusting the next etch step, fabs can pull more wafers back into spec.

Every plant in the process industry most likely has several control loops that do not perform well. Although there are many factors that may negatively affect control loop performance, a few of these ...

Control valve selection plays a crucial role in optimizing control loop performance, and engineers must consider factors beyond just cost, leakage class and pressure drop. As explored in a Control ...

also valuable as a concise and easy-to-read reference source on the subject. This new edition provides expanded coverage of pressure, level, flow, temperature, analytical measurement, and process ...

Control loops are said to interact when movement of the final control element of one loop affects not only its own process variable but the process variable of one or more additional control loops as ...

Overlay control based on DI metrology of optical targets has been the primary basis for run-to-run process control for many years. In previous work we described a scenario where optical overlay ...