Chemical mechanical polishing conditioner

A conditioner head for conditioning the polishing surface of a polishing pad. The conditioner head includes a drive element carried for rotation about a longitudinal axis and a disk backing element. The disk backing element carries an abrasive disk and holds the lower surface of the disk in engagement with the polishing pad. The conditioner head further includes a driven element coupling the disk backing element to the drive element to transmit torque and rotation therebetween. The driven element is longitudinally movable between retracted and extended positions. An annular diaphragm spans a gap between the drive element and the driven element and is coupled to the drive element and to the driven element to rotate therewith as a unit.