Remote plasma clean process with cycled high and low pressure clean steps

Abstract

A remote plasma process for removing unwanted deposition build-up from one or more interior surfaces of a substrate processing chamber after processing a substrate disposed in the substrate processing chamber. In one embodiment, the substrate is transferred out of the substrate processing chamber and a flow of a fluorine-containing etchant gas is introduced into a remote plasma source where reactive species are formed. A continuous flow of the reactive species from the remote plasmas source to the substrate processing chamber is generated while a cycle of high and low pressure clean steps is repeated. During the high pressure clean step, reactive species are flown into the substrate processing chamber while pressure within the substrate processing chamber is maintained between 4-15 Torr. During the low pressure clean step, reactive species are flown into the substrate processing chamber while reducing the pressure of the substrate processing chamber by at least 50 percent of a high pressure reached in the high pressure clean step.