Method and apparatus for preventing plasma formation
AssigneeMicron Technology, Inc.
InventorKevin G. Donohoe
Life of this patent
Estimating the term…
Abstract
A plasma etching device is described in which gas is introduced into a reaction chamber through holes in a gas distribution plate. An electrode ignites the source gas into a plasma by capacitive coupling, and sustains the plasma by inductive coupling. A localized shield structure is provided which suppresses the electric field in locations in or near the holes of the gas distribution plate. Thus, plasma ignition in or near these holes is prevented, and hole lightup effects are avoided. By virtue of eliminating hole lightup, improved flexibility in gas distribution plate design and alignment is provided.
Claims38
A plasma etching device for etching selected materials during integrated circuit fabrication, comprising:
- a reaction chamber adapted to receive the selected materials;
- an electrode operable to produce an electromagnetic field for application to the gas within the reaction chamber to ignite a plasma therewithin;
- a gas flow structure adjoining the reaction chamber and positioned between the electrode and the reaction chamber including an opening through which gas flows into the reaction chamber;
- and
- a shield structure interposed between the electrode and the opening operable and positioned to suppress the electromagnetic field in a location adjacent to and within the opening to prevent plasma formation therewithin.
A plasma etching device for etching selected materials during integrated circuit fabrication, comprising:
- a chamber adapted to receive gas therewithin;
- an electromagnetic field source coupled with the chamber and operable to apply an electromagnetic field to the gas to ignite and sustain a plasma within the chamber;
- a gas distribution plate including a plurality of openings operable to pass the gas into the chamber positioned adjacent to the chamber and between the chamber and the electromagnetic field source, and;
- a shield structure including a plurality of local shields, and each adapted to be coupled to a corresponding source of controlled electric potential, wherein each of the local shields is positioned in a location adjacent to a corresponding one of the openings, the local shields substantially suppressing the electromagnetic field in locations adjacent to the local shields.
The plasma etching device of claimed 10 wherein the electromagnetic field source includes an electrode positioned adjacent to the chamber.
A method of forming a plasma from a gas contained within a chamber, comprising the steps of:
- introducing a source gas into the chamber through a gas flow opening;
- applying an electromagnetic field to the chamber of sufficient magnitude to ignite a plasma therewithin;
- and
- suppressing the magnitude of the applied electromagnetic field at a selected location adjacent to and within the gas flow opening to prevent ignition of a plasma at the selected location.
In a plasma etching device including a gas distribution device having an opening through which gas flows into a reaction chamber, the reaction chamber adapted to receive material to be etched by a plasma formed by application of an electromagnetic field to the gas, a method of preventing plasma formation at a region surrounding the opening and within the opening, comprising the step of suppressing the electromagnetic field in a location adjacent to the opening.
In a plasma etching device including a gas distribution plate having a plurality of openings through which gas flows into a reaction chamber, the reaction chamber adapted to receive material to be etched by a plasma formed by application of an electric field to the gas, a method of preventing plasma formation at regions surrounding the openings and within the openings, comprising the step of suppressing the electric field in at least one location adjacent to a corresponding one of the openings.
An etching system for etching selected materials, comprising:
- a gas supply operable to provide source gas;
- a power generator operable to provide a power sufficient to produce a plasma from the source gas;
- and
- a plasma etching device coupled with the gas supply and with the power generator, and including:
- a reaction chamber adapted to receive the selected materials;
- a gas flow structure adjoining the reaction chamber and operable to receive the source gas provided by the gas supply, the gas flow structure including an opening through which the source gas flows into the reaction chamber;
- an electrode operable to receive the power produced by the power generator and correspondingly producing an electromagnetic field for application to the source gas within the reaction chamber to ignite a plasma;
- and
- a shield structure operable and positioned to suppress the electromagnetic field in locations adjacent to and within the opening to prevent plasma formation in these locations.
Dependencies are inferred from the claim text.