Chemical mechanical polishing method using foamed slurry and apparatus for foamed slurry generation

A spray bar assembly, comprising:

• a dispense arm;
• a polishing liquid supply line routed along the dispense arm;
• a surfactant supply line;
• a gas supply line;
• a foam sprayer nozzle assembly comprising a nozzle body and coupled to the polishing liquid supply line, the surfactant supply line, and the gas supply line, the foam sprayer nozzle assembly configured to dispense a polishing foam on a polishing pad;
• and
• a controller coupled to the spray bar assembly and configured to cause the spray bar assembly to:
• create a polishing foam using a polishing liquid, a surfactant, and a gas using the foam sprayer nozzle assembly;
• and
• dispense, using the dispense arm, the polishing foam onto a polishing pad.

A method of polishing a substrate, comprising:

• placing a substrate on a polishing pad of a polishing apparatus;
• creating a polishing foam using a polishing liquid, a surfactant, and a gas;
• dispensing the polishing foam onto the polishing pad;
• and
• rotating the polishing pad to polish the substrate.