Patent ID: 6120352
Filing Date: 2000-09-19
Classification: B24B,B24D

Abstract:
A process for lapping a surface comprising:a) providing a work piece to be lapped, having at least one surface to be lapped,b) providing a rotating platen having I) a back surface and ii) a flat surface which can be adjusted to a position parallel to said at least one surface of said work piece, said flat surface of said platen having openings therein through which air may flow,c) providing a sheet of abrasive material having an abrasive face comprising abrasive particles bonded to said sheet on said abrasive face and a back side, said back side being on said flat surface of said platen with the abrasive face of said sheet facing said at least one surface to be lapped,d) reducing gaseous pressure between said back side of said abrasive sheet and said flat surface of said platen to secure said sheet of abrasive material to said flat surface of said platen, ande) rotating said platen at a rotational speed of at least 1500 revolutions per minute, andf) contacting said abrasive face and said at least one surface to be lapped on said work piece;wherein said sheet of abrasive material is a round sheet having a) an outer edge having a diameter and b) an inner edge defining a cut-out portion, and said round sheet comprises an annular sheet, said inner edge having a diameter which is greater than one-third the diameter of said outer edge.