SHADOW CLAMP

摘要

A wafer clamping member for clamping a wafer in a plasma reaction chamber. The clamping member has a design which minimizes particle contamination of the wafer and allows more wafers to be processed before it is necessary to clean built-up deposits from the clamping member. The clamping member includes a clamping portion which clamps an outer periphery of the wafer against a bottom electrode and a shadow portion which provides a gap between an inner edge of the clamping member and the upper surface of the wafer. The gap is open to the interior of the plasma reaction chamber and preferably has a height equal to about a mean free path of a gas activated to form a plasma in the plasma reaction chamber.