Mixing frequency at multiple feeding points
AssigneeApplied Materials, Inc.
InventorJonghoon Baek
Life of this patent
Estimating the term…
Abstract
Embodiments disclosed herein generally relate to obtaining a substantially uniform plasma distribution within a large area processing chamber. For large area processing chambers that utilize RF voltages, standing waves can lead to deposition and/or etching non-uniformities. By applying RF voltage in at least two separate locations at two separate, but close frequencies with or without phase modulation, the wave interference pattern moves across the electrode. By moving the standing wave across the electrode, the plasma generated in the chamber can, over time, be substantially uniform.
Claims18
A method, comprising:
- introducing a gas into a processing chamber, the processing chamber having an electrode disposed near a substrate;
- applying a first RF voltage of a first frequency to the electrode at a first location;
- applying a second RF voltage of a second frequency different than the first frequency to the electrode at a second location spaced from the first location, the second frequency and the first frequency differ by less than about 1 MHz and are applied substantially simultaneously;
- igniting the gas into a plasma;
- and
- processing the substrate with the plasma.
A plasma enhanced chemical vapor deposition method, comprising:
- introducing a processing gas through a backing plate at a first location and into a plenum;
- flowing the processing gas from the plenum through a gas distribution showerhead and into a processing area of a processing chamber;
- applying a first RF voltage from a first RF power source at a first frequency to the backing plate at a second location spaced from the first location;
- applying a second RF voltage from a second RF power source at a second frequency different by less than about 1 MHz from the first frequency, the second RF voltage applied at a third location spaced from the first location and the second location, the second RF voltage applied substantially simultaneously with the first RF voltage;
- igniting the processing gas into a plasma;
- and
- depositing material onto a substrate disposed in the processing chamber near the gas distribution showerhead.
A plasma enhanced chemical vapor deposition apparatus, comprising:
- a backing plate;
- a gas distribution showerhead electrically coupled to the backing plate, the gas distribution showerhead having a plurality of gas passages extending therethrough;
- a first RF power source coupled to the backing plate at a first location, the first RF power source capable of producing a first RF voltage at a first frequency;
- and
- a second RF power source coupled to the backing plate at a second location separate from the first location, the second RF power source capable of producing a second RF voltage at a second frequency that differs from than the first frequency.
Dependencies are inferred from the claim text.