Cluster tool soft etch module and ECR plasma generator therefor
AssigneeMaterials Research Corporation
InventorEbrahim Ghanbari
Life of this patent
Estimating the term…
Abstract
An electron cyclotron resonance plasma generator is provided in a semiconductor wafer plasma processing apparatus and cluster tool module, particularly for use in soft etching. The generator generates a uniform plasma by rotating a plasma producing resonance supporting magnetic field about the axis of a resonance cavity within the vacuum chamber of a plasma processor. The rotated field preferably is a single-cusp or multicusp field. Gas uniformly flows into and through the cavity from a gas distribution shower. Microwave energy is evenly divided and coupled into the cavity in a TM.sub.01 mode by a plurality of axially and radially aligned loops.
Claims40
A silicone wafer plasma processing apparatus comprising:
- a sealed chamber containing a gas and having a wafer transferring port in a wall thereof communicating with a vacuum transfer chamber of a wafer transfer module of a wafer processing cluster tool, the port having a valve therein for sealing the sealed chamber from the transfer chamber;
- a high vacuum pump having an inlet communicating with the sealed chamber so as to produce a vacuum pressure level in the gas in the sealed chamber;
- a plasma generation cavity in the sealed chamber;
- a wafer holder to support the wafer with a side thereof facing the cavity;
- a source of microwave energy;
- means for coupling the microwave energy from the source into the cavity;
- a magnet assembly including a plurality of magnets positioned around the cavity, the magnets having a strength and configuration for producing a plurality of magnetic field portions each sufficient in strength to produce electron cyclotron resonance in the cavity to generate a plasma of the gas, the field portions defining regions at which the plasma the plasma is located within the cavity;
- and,
- means for rotating the assembly, including the magnets, as a unit around the cavity to rotate the field portions, the regions and the plasma therewith within the cavity.
A silicone wafer plasma processing apparatus comprising:
- a sealed chamber;
- means for supplying gas to the chamber;
- vacuum pump means for reducing the gas within the chamber to a vacuum pressure level;
- a plasma generation cavity in the chamber;
- a wafer holder mounted in the chamber for supporting thereon a wafer to be processed;
- a source of microwave energy coupled into the cavity;
- rotatable magnet means positioned around the cavity, the magnet means including a rotatable assembly of a plurality of magnets, the rotatable assembly having magnets of a strength and configuration for producing a magnetic field within the cavity having a sufficient strength to produce electron cyclotron resonance at regions within the cavity to thereby produce a plasma in the regions;
- and,
- means for rotating the entire assembly and magnets thereof as a unit around the cavity to rotate the fields, the regions at which the electron cyclotron resonance is produced and the plasma in the regions within the cavity.
A plasma generator for a semiconductor wafer plasma processor comprising:
- a vacuum chamber having a tubular side wall, a gas introduction port, a gas evacuation port, and a plasma generating cavity surrounded in part by the tubular wall thereof;
- a microwave energy source having an output connected to thereto;
- means for coupling from the output into the cavity microwave energy from the source;
- a rotatable assembly including a plurality of magnets spaced outside of the tubular wall of the cavity and rotatably mounted with respect thereto, the magnets being oriented and configured to generate a magnetic field within the cavity, the magnetic field being of sufficient strength and configuration to produce electron cyclotron resonance within the cavity in a plurality of distinct plasma generation regions where the plasma is produced, the field having magnetic lines of force defining the shape and location of the regions;
- and,
- means for rotating the assembly, including the magnets as a unit to rotate the magnetic field, the regions and the plasma about an approximate centerline of the cavity.
A method of plasma processing semiconductor wafers comprising the steps of:
- supplying a gas at a vacuum pressure level within a chamber;
- coupling microwave energy into a cavity within the chamber;
- producing a magnetic field within the cavity with magnets located outside of the chamber;
- producing, with the microwave energy and the magnetic field, electron cyclotron resonance in the gas at regions within the cavity;
- generating a plasma at the regions within the cavity;
- rotating the entire magnetic field with which the electron cyclotron resonance is produced, and thereby the regions and the plasma, about an axis of the cavity;
- and,
- processing with the rotated plasma a wafer positioned in the chamber.
Dependencies are inferred from the claim text.