In some embodiments, the substrate processing apparatus includes a chamber body; Disposed on top of the chamber body cover; Target assembly coupled to the cover, includes a target composed of a material to be deposited on a substrate; Cancer annular space shield having an inner wall disposed around the outer edge of the target; A seal ring disposed adjacent to the outer edge of the female shielded space; And between a support member is coupled near the distal end to the cover, said seal ring and said annular arm space and extends radially inward to support the shield, the support member and the seal ring and the seal ring and the target assembly so that the seal is formed, when coupled to the lid may comprise a said support member to provide sufficient compression.