Abstract: A carrier device in semiconductor processing equipment includes a base and an edge ring. The base includes a base body configured to carry a wafer and has an outer diameter smaller than a diameter of the wafer. The edge ring surrounds the base and has an outer diameter greater than the diameter of the wafer. An outer circumferential surface of the base body faces and is spaced from an inner circumferential surface of the edge ring to form a first annular channel. The first annular channel communicates with a gas supply system. When the base body carries the wafer, an upper surface of the edge ring faces and is spaced from a lower surface of the wafer to form a second annular channel. The first annular channel communicates with the second annular channel.