Patent ID: 9144878
Filing Date: 2015-09-29
Classification: B24B,H01L

Abstract:
1. A polishing apparatus comprising: a polishing table having a surface for disposing a polishing pad; a table drive shaft configured to rotate the polishing table; a substrate holding device configured to hold a substrate so as to press a surface of the substrate against the polishing pad; a dressing unit having a dressing surface in sliding contact with the polishing pad; a dresser swing shaft configured to swing the dressing unit between a position on the polishing table and a position outside the polishing table; a dresser drive shaft configured to rotate the dressing unit; a sensor that detects, every predetermined time, at least one value of a value of rotation speed of the table drive shaft, a value of rotation torque of the table drive shaft, a value of rotation speed of the dresser drive shaft, a value of rotation torque of the dresser drive shaft, and a value of swing torque of the dresser swing shaft; a control unit configured to calculate a change quantity of values of rotation speed of the table drive shaft, a change quantity of values of rotation torque of the table drive shaft, a change quantity of values of rotation speed of the dresser drive shaft, a change quantity of values of rotation torque of the dresser drive shaft, or a change quantity of values of swing torque of the dresser swing shaft based on the detected value(s); and to determine whether or not the change quantity exceeds a predetermined value.