Processing apparatus and polishing surface shaping method

Abstract

A processing apparatus includes a chuck table having a holding surface for holding a workpiece thereon, a chuck table rotary actuator for rotating the chuck table, a polishing unit on which a polishing pad having a polishing surface for polishing the workpiece is mounted, a polishing pad rotary actuator for rotating the polishing pad, a polishing moving mechanism for moving the chuck table and the polishing pad relatively to each other, a shape measuring instrument for measuring a shape of the holding surface, a shaping mechanism for shaping the polishing surface while in contact therewith, a shaping moving mechanism for moving the polishing pad and the shaping mechanism relatively to each other, and a controller for making the polishing surface complementary in shape to the holding surface.

What is claimed is: 
     
         1 . A processing apparatus comprising:
 a chuck table having a holding surface for holding a workpiece thereon;   a chuck table rotary actuator for rotating the chuck table about an axis extending across the holding surface;   a polishing unit on which a polishing pad having a polishing surface for polishing the workpiece is mounted;   a polishing pad rotary actuator for rotating the polishing pad about an axis extending across the polishing surface;   a polishing moving mechanism for moving the chuck table and the polishing pad relatively to each other along a first direction across the holding surface and the polishing surface;   a shape measuring instrument for measuring a shape of the holding surface;   a shaping mechanism for shaping the polishing surface while in contact therewith;   a shaping moving mechanism for moving the polishing pad and the shaping mechanism relatively to each other along a second direction across the first direction; and   a controller for controlling shaping of the polishing surface with the shaping mechanism depending on the shape of the holding surface that has been measured by the shape measuring instrument, thereby to make the polishing surface complementary in shape to the holding surface.   
     
     
         2 . The processing apparatus according to  claim 1 , wherein
 a diameter of the polishing pad is at least twice a diameter of the workpiece.   
     
     
         3 . The processing apparatus according to  claim 1 , wherein
 the shaping mechanism has a shaping member for shaping the polishing surface while in contact therewith and a displacement measuring instrument for measuring an amount of displacement of the shaping member in the first direction, and   the controller specifies a shape of the polishing surface on a basis of the amount of displacement of the shaping member that has been measured by the displacement measuring instrument when the shaping member has contacted the polishing surface at a plurality of positions.   
     
     
         4 . A polishing surface shaping method comprising:
 measuring a shape of a holding surface of a chuck table for holding a workpiece thereon; and   shaping a polishing surface of a polishing pad for polishing the workpiece by bringing a shaping member for shaping the polishing surface into contact with the polishing surface depending on the shape of the holding surface that has been measured in the measuring of the holding surface, thereby to make the polishing surface complementary in shape to the holding surface.   
     
     
         5 . The polishing surface shaping method according to  claim 4 , further comprising:
 specifying a shape of the polishing surface on a basis of an amount of displacement of the shaping member when the shaping member has contacted the polishing surface shaped in the shaping at a plurality of positions.   
     
     
         6 . The polishing surface shaping method according to  claim 4 , wherein
 the holding surface of the chuck table is of a conical shape, and   in the shaping, the polishing surface of the polishing pad is shaped to form in the polishing surface an annular recess that is complementary in shape to the holding surface.