Method and apparatus for reactive sputtering employing two control loops

摘要

The present invention is a cascade control system for reactive sputtering deposition. A first control loop modifies the power supply in order to keep a monitored value nearly constant. This first control loop can be done relatively quickly. A second control loop monitors a second measure parameter in order to control the reactive gas flow to the system. In a preferred embodiment, the slower control loop is used to maintain a relatively constant power at the power supply.