Patent ID: 8118940

Claim:
A clamping mechanism for a semiconductor substrate comprising: a C-shaped pickup plate having an inner periphery portion, an outer periphery portion, and a cutout portion, the C-shaped pickup plate having a top surface for contacting and supporting a semiconductor substrate thereon; a susceptor top plate having a periphery adapted to receive and support the inner periphery portion of the C-shaped pickup plate thereon so as to move upward together with the C-shaped pickup plate, wherein a substrate supporting surface for placing a semiconductor substrate thereon is constituted by the top surface of the C-shaped pickup plate and a top surface of the susceptor top plate, the outer periphery portion of the C-shaped pickup plate having a diameter greater than that of the susceptor top plate; and a clamp comprising (i) a top ring portion for clamping the substrate by contacting and downwardly pressing a periphery of the substrate against the top surface of the C-shaped pickup plate and (ii) a pickup plate supporting portion for lifting upward, apart from the susceptor top plate, the outer periphery portion of the C-shaped pickup plate together with the substrate placed on the top surface of the C-shaped pickup plate, wherein the top ring portion and the pickup plate supporting portion are fixedly vertically distanced, and the top ring portion, the pickup plate portion, and the C-shaped pickup plate are in vertical alignment such that the C-shaped pickup plate is movable between the top ring portion and the pickup plate supporting portion, and the top ring portion, the C-shaped pickup plate, and the susceptor top plate are in vertical alignment such that the clamp is movable upward together with the C-shaped pickup plate and the susceptor top plate, wherein the clamp has an upright F-shaped vertical cross section, wherein the long horizontal portion of the F-shape corresponds to the top ring portion, and the short horizontal portion of the F-shape corresponds to the pickup plate supporting portion.