| 摘要 |
<p>An apparatus for CVD processing is described wherein a wafer (10) mounted on a vertically movable susceptor (40) beneath a gas outlet (20) or showerhead is raised into contact with a shield ring (50) which normally rests on a ring support (70) in the chamber (2). The shield ring (50) engages the frontside edge (11) of the wafer (10), lifting the shield ring (50) off its support (70), when the susceptor (40) and the wafer (10) are raised to a deposition position in the chamber (2). The shield ring (50), by engaging the frontside edge of the wafer (10), shields the edge of the top surface of the wafer (10) as well as the end edge and the backside of the wafer, during the deposition. Matching tapered edges (44, 54) respectively, on the susceptor (40) and the shield ring (50) permit alignment of the shield ring (50). Alignment means (52, 72) are also disclosed to circularly align the shield ring (50) to its support (70) in the chamber (2). <IMAGE></p> |
