WAFER SUPPORT ASSEMBLY OF CARRIER HEAD FOR CMP APPARATUS TO PREVENT WAFER FROM BEING BROKEN BY PHYSICAL EXTERNAL FORCE AND AVOID CONCENTRATION OF STRESS ON EDGE OF WAFER IN WAFER POLISHING PROCESS

摘要

PURPOSE: A wafer support assembly of a carrier head for a CMP(chemical mechanical polishing) apparatus is provided to prevent a wafer from being broken by physical external force and avoid concentration of stress on the edge of the wafer in a wafer polishing process by embodying a membrane plate structure capable of closely and horizontally aligning the wafer. CONSTITUTION: A ring-shaped membrane(15) has a wafer mount surface for mounting a wafer(1). A membrane holder(2) mounts the membrane. A plurality of through holes(12) are formed in the center and the circumference of a membrane plate(11). A membrane clamp(16) fixes the outer edge part of the membrane, positioned on the membrane plate. A membrane holder shaft(23) is capable of moving up/down along the inner wall surface of a holder housing(24), coupled to the upper part of the membrane clamp. A membrane clamp housing(29) is fixedly inserted into the through hole formed in the center of the membrane holder shaft. A membrane washer is formed in the inner center of the membrane clamp housing. A plurality of through holes are formed in the circumference of one through hole formed in the center of the membrane plate, and the bottom surface of the membrane plate is a flat surface parallel with the surface of the ground.