Fluorine process for cleaning semiconductor process chamber

Abstract

<heading lvl="0">Abstract of Disclosure</heading> A process for removing residue from the interior of a semiconductor process chamber using molecular fluorine gas (F2) as the principal precursor reagent. In one embodiment a portion of the molecular fluorine is decomposed in a plasma to produce atomic fluorine, and the resulting mixture of atomic fluorine and molecular fluorine is supplied to the chamber whose interior is to be cleaned. In another embodiment the molecular fluorine gas cleans the semiconductor process chamber without any plasma excitation. Molecular fluorine gas has the advantage of not being a global warming gas, unlike fluorine-containing gas compounds conventionally used for chamber cleaning such as NF3, C2F6 and SF6.

Description

Background of InventionField of the Invention[0001] The invention relates to processes for cleaning or removing residue from the interior surfaces of a vacuum chamber used for fabricating electronic devices. More specifically, the invention relates to the use of fluorine gas in such a process.Background of the Invention[0002] Processes for fabricating electronic devices containing semiconductors generally include steps in which layers or features of material are deposited or patterned (i.e., etched) within a vacuum chamber, generally called a semiconductor process chamber. The chemical byproducts and unused reagents of such deposition or etch processes are mostly exhausted from the chamber by an exhaust pump, but some residue unavoidably deposits on the chamber wall and on other surfaces within the chamber. Such residue must be cleaned or removed periodically in order to maintain consistent process conditions and to prevent the residue from flaking off and contaminating the electron...

AI Technical Summary

Benefits of technology

0005] The invention is a process for cleaning or removing residue from the interior of a semiconductor process chamber using molecular fluorine gas (F.sub.2) as the principal precursor reagent. Molecular fluorine gas has the advantage of not being a global warming gas, unlike other fluorine-containing gas compounds conventionally used for chamber cleaning such as NF.sub.3, C.sub.2F.sub.6 and SF.sub.6.

0006] I discovered that fluorine atoms and radicals produced by plasma decomposition of molecular fluorine gas effectively remove silicon, silicon oxide, and silicon nitride residues. In addition, I discovered that molecular fluorine gas effectively removes silicon residues without any plasma.

Problems solved by technology

The chemical byproducts and unused reagents of such deposition or etch processes are mostly exhausted from the chamber by an exhaust pump, but some residue unavoidably deposits on the chamber wall and on other surfaces within the chamber.

One disadvantage of cleaning processes using such fluorine-containing gas compounds is that such gases are believed to contribute to global warming if they are released to the earth's atmosphere after use.