Patent ID: 8671965

Claim:
A method for controlling application of a tuning fluid and a process fluid to a process chamber, comprising: (a) enabling flow of the tuning fluid to a center supply of the process chamber through a first supply network, the first supply network coupled to a cross-flow network that includes a closed cross-flow valve; (b) enabling flow of the process fluid to an edge supply of the process chamber through a second supply network, the second supply network coupled to the cross-flow network, the process fluid flowing to the edge supply; (c) disabling flow of the process fluid through the cross-flow network; (d) activating a purge of the second supply network that connects between the edge supply of the chamber and the cross-flow network; (e) activating a purge of the second supply network that connects between a source of the process fluid and the cross-flow network; and (f) after performing the purge of (d) and (e), enabling a flow of a new process fluid through the cross-flow network to the edge supply of the process chamber.