Patent ID: 6447382
Filing Date: 2002-09-10
Classification: B24B

Abstract:
A double-sided polishing machine, comprising:an upper polishing disk, a lower polishing disk, and runner disks on the lower polishing disk having openings for accommodating wafers, the runner disks being moved between the polishing disks upon rotation of the polishing disks for machining both surfaces of the wafers; control means adapted to stop the movement of the runner disk such that the runner disks attain a precise predetermined position on the lower polishing disk; an unloader assembly provided adjacent the polishing machine and said unloader assembly having a single arm member supporting a suction head designed to rotate about a first vertical axis, the suction head being provided with a plurality of suction ports for a contemporary engagement of all wafers in a runner disk, the arm member having a vertical axis at a predetermined spacing from the first vertical axis about which the arm member is rotatably supported between a first position wherein the suction head is above a lay-down device and a second position wherein the first vertical axis of a suction head is aligned with the center of one runner disk in the predetermined position, the runner disk further having a mark associated with one opening of the runner disk and the suction head having one sensor for detecting the mark during rotation of the suction head aligned with the runner disk to align the suction ports with the individual wafers in the runner disk.