Patent ID: 7527544

Claim:
A system for polishing semiconductor wafers comprising: a. a semiconductor wafer polisher comprising a rotatable turntable, a polishing pad removably affixed to a first surface of the turntable, and a rotatable wafer ring adapted to hold a semiconductor wafer against the polishing pad during wafer polishing; b. a polishing pad offset dial gage having a frame having a surface adapted for positioning against an outer peripheral edge of the turntable, a sensor pin having a free tip positioned to engage an outer peripheral edge of the polishing pad, and a data readout providing distance measurements as a function of radial displacement of the sensor pin tip from an initial position; wherein measurement by the dial gage of the radial displacement between the polishing pad peripheral edge and the turntable peripheral edge provides information as to the acceptability of polishing pad placement prior to polishing semiconductor wafers.