In-situ pre-clean for electroplating process
AssigneeApplied Materials, Inc.
InventorsRajeev Bajaj, Ramin Emami
Life of this patent
Estimating the term…
Abstract
Embodiments of the invention generally provide a waveform to be applied to a seed layer prior to initiating plating operations, wherein the waveform is configured to remove organic contaminants from the seed layer. The application of the waveform generally includes applying a plurality of anodic pulses to the seed layer prior to an electrochemical deposition process and subsequent to the seed layer contacting a plating solution, and applying a cathodic pulse to the seed layer immediately following each of the plurality of anodic pulses. The waveform is generally provided by a power supply in electrical communication with a system controller configured to supply controlling signals to the power supply.
Claims33
A method for cleaning organic contaminants from a copper seed layer in an electrochemical plating system, comprising:
- applying a plurality of anodic pulses to the seed layer prior to an electrochemical deposition process and subsequent to the seed layer contacting a plating solution;
- and
- applying a cathodic pulse to the seed layer immediately following each of the plurality of anodic pulses.
A method for removing organic contamination from a copper seed layer overlying sub-quarter micron sized features formed onto a semiconductor substrate in an electrochemical plating system, the method comprising applying a cleaning waveform to the seed layer once the seed layer is immersed in an electrolyte solution, the cleaning waveform comprising:
- at least one deposition pulse;
- and
- at least one etch pulse, wherein the at least one deposition pulse has a long duration low magnitude positive current density, and wherein the at least one etch pulse has a short duration high magnitude negative current density.
A method for electrochemically plating copper onto a seed layer, comprising:
- immersing the seed layer in a plating solution while applying an electrical loading bias to the seed layer;
- applying a cleaning waveform to the seed layer prior to initiating plating operations, the cleaning waveform comprising:
- a plurality of cathodic pulses;
- and
- a plurality of anodic pulses, the plurality of anodic pulses having a short duration and high current density;
- and
- applying a electrical plating bias to the seed layer to plate copper thereon.
A method for cleaning contaminants from a copper seed layer, comprising alternating the application of an anodic pulse and a cathodic pulse, wherein the cathodic pulses have a duration of between about 10 milliseconds and about 100 milliseconds and a current density of between about 75 mA/cm2 and about 125 mA/cm2, and wherein the anodic pulses have a duration of between about 5 milliseconds and about 20 milliseconds and a current density of between about 75 mA/cm2 and about 125 mA/cm2, the alternating application of the anodic pulse and the cathodic pulse occurring prior to commencing a plating process on the seed layer.
An electrochemical plating cell, comprising:
- a plating cell container configured hold a plating solution therein;
- a pivotally mounted lid member configured to support a substrate on a lower surface thereof such that the substrate is in electrical communication with a contact ring;
- and
- a power supply in electrical communication with the contact ring, the power supply being configured to apply a plurality of anodic pulses to a seed layer deposited on the substrate prior to an electrochemical deposition process and subsequent to the seed layer contacting a plating solution and apply a cathodic pulse to the seed layer immediately following each of the plurality of anodic pulses.
An electrochemical plating cell, comprising:
- a plating cell container configured hold a plating solution therein;
- a pivotally mounted lid member configured to support a substrate on a lower surface thereof such that the substrate is in electrical communication with a contact ring;
- means for applying a plurality of anodic pulses to a seed layer deposited on the substrate prior to an electrochemical deposition process and subsequent to the seed layer contacting a plating solution;
- and
- means for applying a cathodic pulse to the seed layer immediately following each of the plurality of anodic pulses.
Dependencies are inferred from the claim text.