Patent ID: 9289876
Filing Date: 2016-03-22
CPC Classification: B24B,H01L

Claim Text:
1. A method for polishing a work, in which work held in a retaining opening provided in a carrier plate, the center of the retaining opening being positioned apart from the center of the carrier plate, is sandwiched between an upper plate and a lower plate each provided with a polishing pad; the carrier plate is rotated by a drive mechanism; and the upper plate and the lower plate are also rotated, so that the distance between the center of the upper plate and the lower plate and the center of the work changes periodically with the rotation of the carrier plate, and front and back surfaces of the work are simultaneously polished with the polishing pads comprising the steps of: measuring at least one of torque of the drive mechanism, the upper plate, and the lower plate; and controlling an amount of polishing removal of the work based on the fluctuation of the torque component, on the torque component at the time when a certain angle of rotation of the carrier plate is achieved, or on the difference between the torque components at the times when two certain different angles of rotation of the carrier plates are achieved, due to the periodic change in the distance.