Multi-port pumping system for substrate processing chambers
An exhaust foreline for purging fluids from a semiconductor fabrication chamber is described. The foreline may include a first, second and third ports independently coupled to the chamber. A semiconductor fabrication system is also described that includes a substrate chamber that has a first, second and third interface port. The system may also include a multi-port foreline that has a first, second and third port, where the first foreline port is coupled to the first interface port, the second foreline port is coupled to the second interface port, and the third foreline port is coupled to the third interface port. The system may further include an exhaust vacuum coupled to the multi-port foreline.
1. A method of operating a substrate processing system having a substrate processing chamber and a gas exhaust system comprising a turbo molecular pump, a gate valve that can be closed to fluidly isolate the turbo molecular pump from the substrate processing chamber and first and second gas exhaust pathways that are fluidly coupled to an exhaust foreline, the method comprising:
transferring a substrate into the chamber and performing a substrate processing operation on the substrate by introducing one or more process gases into the chamber while the substrate is positioned within the chamber and exhausting the one or more process gases from the chamber into the exhaust foreline with the turbo molecular pump through the first exhaust pathway fluidly coupled to the chamber at a first port downstream from the turbo molecular pump, wherein unwanted residue material builds-up on interior surfaces of the substrate processing chamber during the substrate processing operation; and
transferring the substrate out of the chamber, closing the gate valve to isolate the turbo molecular pump from the chamber and performing a chamber clean operation by introducing an activated cleaning gas mixture into the chamber, reacting at least a portion of the cleaning gas mixture with the residue material, and removing the cleaning gas mixture from the chamber through the second exhaust pathway having at least second and third ports fluidly coupled to the chamber upstream from the turbo molecular pump.
2. The method of claim 1 wherein the second exhaust pathway includes a fourth port fluidly coupled to the chamber upstream from the turbo molecular pump.
3. The method of claim 2 wherein the step of removing the activated cleaning gas mixture comprises fluorine ions and fluorine radicals generated in a remote plasma system operatively coupled to the chamber.
4. The method of claim 3 wherein the fluorine ions and fluorine radicals are generated from NF 3 .