| 摘要 |
PROBLEM TO BE SOLVED: To provide a grinding device which efficiently grinds a wafer to improve thickness accuracy of a recessed part when the recessed part is formed in a center portion of the wafer.SOLUTION: A grinding device 1 includes: holding means 4 for holding a lower surface Wb of a wafer W; and grinding means 10 for grinding a center portion of an upper surface Wa of the wafer W. The holding means 4 includes: a chuck table 5 in which a holding surface 6a of the wafer W is formed on a flat surface; and a chuck table rotary mechanism 7 which rotates the chuck table 5 around its axis. The grinding means 10 includes: a grinding wheel 11 in which grind stones 112 are disposed on a wheel base 111 so as to form a ring shape; and a spindle unit 12 to which the grinding wheel 11 is rotatably attached. In the grinding wheel 11, an outer surface 113 of each grind stone 112 contacts with an inner surface of a recessed part W3. A diameter D of an outer periphery of the grind stones 112 is equal to or larger than a radius r of the recessed part W3 and is equal to or smaller than a diameter R of the recessed part W3. The grind stones 112 constantly pass a center O of the wafer W. The structure allows the grinding device 1 to efficiently grind the wafer W with high thickness accuracy.SELECTED DRAWING: Figure 5 |
