| 摘要 |
PROBLEM TO BE SOLVED: To provide a polishing method of a workpiece which can control a polishing amount of the workpiece with higher accuracy.SOLUTION: In a polishing method of a workpiece, the workpiece 20 held by a holding hole 40 arranged on a carrier plate 30 and having a center in a position separated from a center of the carrier plate 30 is sandwiched by an upper surface plate 50a and a lower surface plate 50b respectively having polishing pads 60a and 60b. A distance between a center of the upper surface plate 50a and the lower surface plate 50b and a center of the workpiece 20 changes periodically at each rotation of the carrier plate 30, and front and rear surfaces of the workpiece 20 are simultaneously polished. A torque is measured, and a polishing amount of the workpiece 20 is controlled based on an amplitude of a torque component caused by the periodical change of the distance. An opening part H is formed on a part except for the holding hole 40 on the carrier plate 30. An opening ratio of the carrier plate 30 is 55% or less.SELECTED DRAWING: Figure 6 |
