Patent ID: 6753964
Filing Date: 2004-06-22
Classification: H01L

Abstract:
An axis determination apparatus for determining a center axis line of a surface of a circular substrate, comprisinga support mount for supporting said substrate placed on a surface thereof, a drive mechanism for rotating said support mount in a plane containing the surface of said support mount, a light-emitting device disposed near a circumferential portion of said support mount, and a light-receiving device disposed, opposite to said light-emitting device, near said circumferential portion of said support mount, said light-emitting device emitting a beam of light to said light-receiving device, wherein said light-receiving device is disposed so as to receive said beam of light emitted by said light-emitting device only through a notch provided on a circumferential portion of said substrate when said notch is aligned between said light-emitting device and said light-receiving device, and said light-receiving device does not receive emitted light when said notch is not so aligned, a lifter including a support member arranged on a circle greater than said support mount in diameter and a projected member projected towards a center of said circle, for supporting said substrate and a circumferential portion of said substrate sitting on said projected member, and a lifting mechanism for hoisting and lowering said lifter near said support mount, wherein an inclined surface sloped towards said projected member is provided on said support member and said lifter transfers said substrate onto a surface of said support mount when said lifter is lowered below said support mount while supporting said substrate, where the center of said substrate is aligned with the center of the support mount, thereby determining the center of said substrate.