Hydrogen bubble reduction on the cathode using double-cell designs

A electrochemical mechanical polishing system for planarizing substrates, comprising:

• a body having a polishing surface positioned to polish the substrate;
• at least one conductive element in electrical contact with the substrate;
• a first chamber adapted to contain a first electrolyte in communication with the substrate;
• a second chamber;
• said second chamber containing a counter electrode;
• said second chamber adapted to contain a second electrolyte, which contains a greater amount of metal ions than the first electrolyte;
• said second electrolyte being in contact with the counter electrode;
• the chambers being separated by a permeable membrane that prevents permeation of metal ions and gas there through;
• and
• a power source with one terminal in electrical contact with the conductive element and the other terminal in electrical contact with the counter electrode.

A electrochemical mechanical polishing system for planarizing substrates, comprising:

• a body having a polishing surface positioned to polish the substrate;
• at least one conductive element in electrical contact with the substrate;
• a first electrode;
• a first chamber adapted to contain a first electrolyte in communication with the substrate and the first electrode;
• a second chamber;
• said second chamber containing a second electrode;
• said second chamber adapted to contain a second electrolyte in communication with the second electrode;
• the chambers being separated by a permeable membrane that prevents permeation of gas there through;
• and
• a power source with one terminal in electrical contact with the conductive element and the other terminal in electrical contact with the first electrode and the second electrode.

A method for electrochemically polishing a substrate, comprising:

• connecting a substrate to one terminal of a power source;
• disposing the substrate in a first electrolyte;
• connecting a counter electrode to the other terminal of a power source;
• disposing the counter electrode in a second electrolyte;
• disposing a membrane between the substrate and the counter electrode such that the membrane is in contact with both electrolytes, wherein the membrane prevents gas passage;
• applying a bias between the substrate and the counter electrode;
• and
• removing materials from the surface of the substrate disposed in the electrolyte.

A method for electrochemically polishing a substrate, comprising:

• disposing a substrate having a conductive material layer formed thereon in a process apparatus comprising a first electrode and a counter electrode, wherein the substrate is in electrical contact with the first electrode;
• connecting the first electrode to one terminal of a power source;
• disposing the substrate in a first electrolyte;
• connecting the counter electrode to the other terminal of the power source;
• disposing the counter electrode in a second electrolyte;
• disposing a membrane between the substrate and the counter electrode such that the membrane is in contact with the first and second electrolytes, wherein the membrane prevents gas passage;
• applying a pressure to the substrate and a polishing medium by use of a polishing head;
• providing relative motion between the substrate and the polishing medium by mechanical means;
• applying a bias between the first electrode and the counter electrode;
• and
• removing materials from the surface of the substrate disposed in the electrolyte.

A method for electrochemically polishing a substrate, comprising:

• disposing a substrate having a conductive material layer formed thereon in a process apparatus comprising a first electrode and a counter electrode, wherein the substrate is in electrical contact with the first electrode;
• connecting the first electrode to one terminal of a power source;
• disposing the substrate in a first electrolyte;
• connecting the counter electrode to the other terminal of the power source;
• disposing the counter electrode in a second electrolyte;
• disposing a membrane between the substrate and the counter electrode such that the membrane is in contact with the first and second electrolytes, wherein the membrane prevents gas passage;
• disposing a second counter electrode in the first electrolyte;
• connecting the counter electrode and the second counter electrode;
• applying a bias between the first electrode and the counter electrode;
• and
• removing materials from the surface of the substrate disposed in the first electrolyte.