A apparatus includes a susceptor and a non-reactive gas source. The susceptor has through holes and a wafer support surface. Each through hole includes a lift pin and a lift pin head. The lift pin has a vertical degree of motion in the through hole to lift up or place a wafer on the susceptor. The lift pin head has at least one flow channel structure running from its first surface at least partially exposed to a bottom side of the susceptor through its second surface exposed to a top side of the susceptor wherein the lift pin. The non-reactive gas source is configured to flow a gas to a backside of the wafer through the flow channel structure through the bottom side of the susceptor.