Patent ID: 8679944

Claim:
A method of reducing applied mechanical friction when trimming a bonded structure comprising a first wafer of predetermined thickness and comprising electrical components, bonded to a second wafer of predetermined thickness, with the first wafer having a chamfered edge, which method comprises: a first trimming step carried out by mechanical action upon the bonded structure and over a first depth comprising the thickness of the first wafer and a first portion of the thickness of the second wafer, and also being carried out over a first predetermined width from the edge of the first wafer; and at least one second trimming step also carried out by mechanical action upon the bonded structure and over a second depth also comprising the thickness of the first wafer and a second portion of the thickness of the second wafer, while being carried out over a second predetermined width that is less than the first width and also is further from the edge of first wafer than is the first predetermined width.