Method of removing carrier plate

A method of removing a carrier plate from a workpiece of a disk-shaped composite substrate in which the workpiece is disposed on a face side of the carrier plate with a temporary adhesive layer interposed therebetween, comprising:

• a step forming step of forming a step protruding laterally from the carrier plate more on a reverse side of the carrier plate than on the face side of the carrier plate, by removing an outer circumferential portion of the workpiece, an outer circumferential portion of the temporary adhesive layer, and a face-side side of an outer circumferential edge of the carrier plate;
• a starting point region forming step of forming a starting point region by cutting and removing a partial region of the workpiece that extends across the face side of the carrier plate inwardly of, and spaced from, the step protruding form the carrier plate, and from one point on the step to another point on the step;
• a holding step of, after the step and the starting point region have been formed, holding the workpiece from above with a holding unit while the workpiece is positioned above the carrier plate;
• and
• a carrier plate removing step, after the workpiece has been held by the holding unit, peeling off and removing the carrier plate from the workpiece by applying a downward force from a pusher to the step to move the carrier plate in a direction away from the workpiece,
• wherein the starting point region is formed after the step protruding from the carrier plate is formed.