Fixed abrasive polishing pad

An apparatus for performing mechanical polishing of a semiconductor wafer surface, comprising:

• a polishing pad having a polishing face, wherein said polishing pad further comprises,
• a first member having a first polishing surface and comprising a structurally degradable abrasive first material, and,
• a second member having a second polishing surface and comprising a second material that is less degradable and less abrasive than said first material, wherein said first and second polishing surfaces define said polishing face;
• a wafer support having a support surface, said wafer support being disposed opposite to said pad, such that said polishing face and said support surface are substantially parallel and can be brought within close proximity;
• and,
• a motor connected to provide relative motion between said polishing face and said support surface.

A method of limiting mechanical abrasion of a surface during polishing, said method comprising:

• providing a polishing pad including a first member comprising a first material that is abrasive to a wafer surface and structurally degradable during polishing;
• incorporating a second member in the polishing pad comprising a second material that is less degradable and less abrasive than the first material to limit the amount of the first member available to abrade the surface;
• and,
• polishing the wafer surface with the first member.

A method of performing chemical mechanical polishing of a wafer surface, comprising:

• providing a polishing pad having a first member comprising a first material that is abrasive to a wafer surface and erodible in polishing chemicals extending a predetermined distance beyond a second member comprising a second material that is substantially nonerodible in polishing chemicals and substantially nonabrasive to a wafer surface;
• dispensing the polishing chemicals onto the wafer surface;
• and,
• polishing the wafer surface with the first member for a period of time sufficient to erode the first member to be substantially flush with the second member.