Patent ID: 8197300
Filing Date: 2012-06-12
Classification: B24B

Abstract:
1. A method for the correction of grinding spindle orientation in a double-side grinding machine for the simultaneous double-side machining of semiconductor wafers, the grinding machine having two coaxial grinding spindles, each spindle comprising a grinding disk flange for attaching a grinding disk, the method comprising: torsionally coupling the two grinding spindles by a torsional coupling element; providing a measuring unit comprising an inclinometer and at least two sensors for distance measurement; mounting the measurement unit between the grinding disk flanges, the grinding disk flanges having no grinding disks attached thereon, such that the grinding spindles are in the same position they would occupy during a later double-side machining of a semiconductor wafer; rotating the torsionally coupled grinding spindles and determining radial and axial correction values for an axial alignment of the two grinding spindles by means of the inclinometer and the sensors, and using these values to correct an orientation of the two grinding spindles to obtain a symmetrical orientation of the two grinding spindles.