CPC B24B 37/30 (2013.01) [B24B 37/20 (2013.01); H01L 21/6835 (2013.01)] | 18 Claims |
1. A method of forming a carrier wafer, the method comprising the steps of:
lapping a first surface and a second surface of the carrier wafer such that the carrier wafer is substantially flat,
the carrier wafer comprising a glass, glass-ceramic or ceramic material, and
the carrier wafer having a diameter from 250 mm to 450 mm and a thickness from 0.5 mm to 2 mm after lapping; and
polishing the first surface of the carrier wafer with at least one of a differential pressure, a differential speed, or a differential time between a center portion and an edge portion of the carrier wafer such that the first surface has a convex or concave shape,
wherein a total thickness variation across the first surface is from 1 μm to 5 μm after the step of polishing the first surface of the carrier wafer is performed.
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