Device for centering wafers

摘要

A device for centering circular wafers includes a support chuck for supporting a circular wafer to be centered upon its top surface, left, right and middle centering linkage rods and a cam plate synchronizing the rectilinear motion of the left, right and middle centering linkage rods. The left centering linkage rod includes a first rotating arm at a first end and rectilinear motion of the left centering linkage rod translates into rotational motion of the first rotating arm. The right centering linkage rod comprises a second rotating arm at a first end, and rectilinear motion of the right centering linkage rod translates into rotational motion of the second rotating arm. The first and second rotating arms are rotatable around an axis perpendicular to the top surface of the support chuck and comprise a curved edge surface configured to roll against the curved edge of the circular wafer. The middle centering linkage rod includes a third alignment arm at a first end. The third alignment arm is placed in contact with the curved edge of the circular wafer and linear motion of the middle centering linkage rod in the Y-direction pushes the third alignment arm and the circular wafer toward or away from the center of the support chuck. The cam plate includes first and second linear cam profiles. The first cam profile provides rectilinear motion for the middle centering linkage rod and the second linear cam profile provides rectilinear motion for the left and right centering linkage rods.

主权项

1. A device for centering circular wafers, comprising:
a support chuck for supporting a circular wafer to be centered upon its top surface; left centering linkage rod comprising a first rotating arm at a first end, and wherein rectilinear motion of the left centering linkage rod translates into rotational motion of the first rotating arm, and wherein said first rotating arm is rotatable around an axis perpendicular to the top surface of the support chuck and comprises a curved edge surface configured to roll against the curved edge of the circular wafer; right centering linkage rod comprising a second rotating arm at a first end, and wherein rectilinear motion of the right centering linkage rod translates into rotational motion of the second rotating arm, and wherein said second rotating arm is rotatable around an axis perpendicular to the top surface of the support chuck and comprises a curved edge surface configured to roll against the curved edge of the circular wafer; middle centering linkage rod comprising a third alignment arm at a first end, wherein said third alignment arm is placed in contact with the curved edge of the circular wafer and wherein linear motion of the middle centering linkage rod in a Y-direction pushes the third alignment arm and the circular wafer toward or away from the center of the support chuck; and a cam plate synchronizing the rectilinear motions of the left, right and middle centering linkage rods, said cam plate comprising first and second linear cam profiles, wherein said first cam profile provides rectilinear motion for the middle centering linkage rod and said second linear cam profile provides rectilinear motion for the left and right centering linkage rods.