Abstract: A carrier has a plate-shaped carrier body that has an inner hole and is made of a first material, and an insertion member that is shaped such that the insertion member fits between the substrate and an inner circumference of the inner hole, that has a substrate holding hole, and that is made of a second material that is different from the first material. The insertion member has a region that bulges toward the carrier main body side, and when a radius of an inscribed circle inscribed to an inner circumference of the substrate holding hole of the insertion member is R, the center of gravity of the insertion member is located 0.1×R or more away from the center of an inner circumferential shape of the substrate holding hole of the insertion member.