A showerhead provided in a chamber of a semiconductor manufacturing apparatus and facing a wafer holder includes: a disk-shaped member having a plurality of through holes penetrating the disk-shaped member in a direction of a thickness thereof; a high-frequency conductor embedded in the disk-shaped member; a hole provided in the disk-shaped member, extending in the direction of the thickness of the disk-shaped member and having a bottom exposing a portion of the conductor; an electrode terminal portion disposed in the hole and having a base portion electrically connected to the conductor and a columnar portion provided on the base portion; a cylindrical member having a first end portion fitted outside the columnar portion and facing the conductor and a second end portion facing away from the first end portion, and a sealing member surrounding the first end portion.