CMP POLISHING PAD WITH PROTRUDING STRUCTURES HAVING ENGINEERED OPEN VOID SPACE

1 . A polishing pad useful in chemical mechanical polishing comprising

a base pad having a top side,

a plurality of protruding structures on the top side of the base pad, each of the protruding structures having a body, where the body has (i) an exterior perimeter surface defining an exterior shape of the protruding structure, (ii) an interior surface defining a central cavity and (iii) a top surface defining an initial polishing surface area, wherein the body further has openings in it from the cavity to the exterior perimeter surface.

2 . The polishing pad of claim 1 wherein the exterior shape is cylindrical, ellipsoidal, polygonal, of an irregular or regular curved surface.

3 . The polishing pad of claim 1 wherein the central cavity has a shape that is cylindrical, ellipsoidal, polygonal, of an irregular or regular curved surface.

4 . The polishing pad of claim 1 wherein the base pad and the protruding structure are integral to each other.

5 . The polishing pad of claim 1 wherein the top surface is worn down during polishing of a substrate to expose a new polishing surface having a subsequent polishing surface area and the body and openings are such that the initial polishing surface area differs from the subsequent polishing surface area by less than 25% based on initial polishing surface area.

6 . The polishing pad of claim 1 wherein the protruding structure is characterized by a void fraction of 0.1 to 0.96.

7 . The polishing pad of claim 1 having two or more central cavities for each protruding structure.

8 . The polishing pad of claim 1 wherein a Young's modulus of the protruding structure is higher than a Young's modulus of the base pad.

9 . A method comprising

providing a substrate,

polishing the substrate the polishing pad of any one of claims 1 to 6 .

10 . The method of claim 7 wherein a polishing medium is present at an interface between the substrate and the polishing pad during polishing.