Patent ID: 7534166

Claim:
A chemical mechanical polishing (CMP) apparatus for polishing an edge section of a boundary between a front surface and a circumference surface of a disc-shaped wafer, comprising: a disc-shaped polishing member rotatably supported by a shaft; a wafer pressing mechanism for retaining said wafer and pressing said wafer against said polishing member; and a dresser mechanism for dressing said polishing member at a location, which is different from a location where said wafer pressing mechanism presses said wafer, wherein said polishing member includes at least one annular concave trench coaxially formed on a front surface of said polishing member, wherein at least one inner surface of said concave trench is composed of an inclined polishing surface for polishing an edge section of said wafer, said wafer pressing mechanism pressing the edge section of said wafer against at least one inner surface of said concave trench of said polishing member, and wherein said dresser mechanism dresses the inner surface of said concave trench, against which said edge section of said polishing member is pressed.