may be used during lapping the machine is set to apply greater than 1 psi pressure to the carrier wafers the speeds of the pin ring upper and lower plate are set depending on machine attributes to achieve even removal of material from the bottom and top surface of the wafer the grind process may employ a single side grind of each face of the wafer using cross feed or in feed grinder to a target diameter of 410 microns in some embodiments a small batch size is used e g 1 10 wafers at a time the wafer is pulled flat during the grind with porous vacuum chuck after lapping and or grinding the edge profile and laser mark are inspected if the starting thickness of the blank is too high then the laser mark and edge profile may need to be reworked the carrier wafers are then polished to the final target thickness which in some embodiments is of 400 microns in some embodiments the wafer polish system incorporates the following specifications double side polishing machine with plate diameter greater than 30 u2033 carrier diameter greater than 9 u2033 hard intermediate polish pad plate flatness of less than 15 microns steel carriers 300 325 microns thick with a pocket diameter 0 25 mm greater than carrier wafer diameter a diamond particle abrasive suspended in polishing vehicle applied directly to the pad during process alternative abrasives such as boron carbide or silicon carbide may be used apply greater than 1 psi pressure to the carrier wafers during polishing and.