Patent ID: 6864176
Filing Date: 2005-03-08
Classification: B24B,H01L

Abstract:
1. A measurement method for measuring the thickness of a thinned wafer, which comprises the steps of: a) forming a plurality of thickness-inspection patterns on a first side of a first wafer substrate with photolithography; b) forming V-grooves by etching the plurality, of thickness-inspection patterns with anisotropic etching; c) bonding the first side of a first wafer substrate to a second wafer substrate; d) thinning the first wafer substrate by removing substrate from a second side thereof to expose a vertex of at least one of the plurality of V-grooves thereby producing at least one gap on the second side of the first wafer substrate; e) calculating a thickness of the first silicon wafer by measuring a size of the at least one gap on the second side of the first wafer substrate; and f) sorting the first wafer substrate by the thickness thereof calculated from the size of the at least one gap.