Methods and apparatus for cleaning deposition reactors
AssigneeNovellus Systems, Inc.
InventorsPanya Wongsenakhum, Abhishek Manohar
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Abstract
Improved methods of removing tungsten film from the interior reactor and reactor component surfaces between tungsten deposition operations are provided. The methods involve increasing the availability of molecular fluorine to remove tungsten from the reactor while maintaining fast removal rates. Certain embodiments involve a multi-stage process including a stage in which atomic fluorine is introduced at a low pressure (e.g., about 8 Torr or less) and a stage in which molecular fluorine is introduced or allowed to form in the chamber at high pressure (e.g., about 8 Torr or higher).
Claims23
A multi-stage method of removing film deposited on surfaces in deposition chamber using a remote plasma source, the method comprising:
- a first stage in which atomic fluorine is introduced to the deposition chamber at a chamber pressure of no more than about 8 Torr and a second stage in which molecular fluorine is introduced to the deposition chamber at a chamber pressure of at least about 8 Torr.
A method of removing tungsten deposited on pedestal and ceramic ring surfaces in a deposition chamber, the method comprising:
- introducing a fluorine-containing gas to a plasma source remote to the deposition chamber to generate atomic fluorine;
- flowing atomic and/or molecular fluorine from the remote plasma source to a showerhead to be introduced to the deposition chamber;
- introducing atomic and/or molecular fluorine to the deposition chamber via the showerhead;
- and
- exposing the pedestal and ceramic ring surfaces to the atomic and/or molecular fluorine such that the atomic and/or molecular fluorine and deposited tungsten react to form tungsten hexafluoride, to thereby remove at least some of the deposited tungsten, wherein introducing atomic and/or molecular fluorine to the deposition chamber via the showerhead comprises a first stage in which chamber pressure is at no more than about 5 Torr such that amount of atomic fluorine introduced to the chamber is greater than the amount of molecular fluorine introduced to the chamber, and a second stage is which the chamber pressure is at least 10 Torr such that the amount of molecular fluorine introduced to chamber is greater than the amount of atomic fluorine introduced to the chamber.
A method of removing unwanted film deposited on interior surfaces of a deposition chamber including on ceramic ring and pedestal surfaces of a ceramic ring and pedestal within the deposition chamber, wherein said ceramic ring is located between the pedestal and a showerhead in the deposition chamber;
- the method comprising:
- introducing molecular fluorine to the deposition chamber via the showerhead;
- exposing the deposited film to molecular fluorine to thereby cause a reaction that removes the film from the interior surfaces of the deposition chamber including the pedestal and ceramic ring surfaces;
- wherein the chamber pressure is regulated such that a film removal rate from all of the interior surfaces of the deposition chamber is approximately the same as a removal rate from the ceramic ring.
Dependencies are inferred from the claim text.