Patent ID: 7557905
Filing Date: 2009-07-07
Classification: H01L

Abstract:
1. A wafer loading apparatus, comprising: a plate adapted to support a wafer, wherein the plate comprises: a plurality of protrusion elements disposed within the plate and partially extruding above the plate to support the wafer; an upper plate including a plurality of penetrating holes, each surrounding an upper portion of one of the plurality of protrusion elements to prevent the one protrusion element from becoming separated from the upper plate; a connecting plate disposed below the upper plate and Including a plurality of recesses respectively aligned with the plurality of penetrating holes and each surrounding a lower portion of one of the plurality of protrusion elements, wherein each of the lower portions of the plurality of protrusion elements has a larger diameter than a corresponding upper portion; a bottom plate including a plurality of caging recesses respectively disposed below the plurality of recesses; and a plurality of magnetic control elements, each respectively disposed under a corresponding one of the plurality of protrusion elements to control movement of the plurality of protrusion elements, such that a distance between a tower surface of the wafer and an upper surface of the plate is substantially uniform, wherein the plurality of magnetic control elements comprises, a plurality of lower magnetic control elements, each disposed in a corresponding one of the plurality of caging recesses, and a plurality of upper magnetic control elements, each disposed on a bottom surface of a corresponding one of the plurality of protrusion elements.