Patent ID: 7765950

Claim:
An apparatus for sensing a spin chuck for a spin coating unit comprising: a spin chuck which sucks a wafer with vacuum pressure to allow the wafer to be placed thereon; a rotary shaft which is rotated by driving of a motor below the spin chuck correspondingly thereto, and whose upper end is engaged with the spin chuck so as to interlock with the rotation of the spin chuck, a shaft guide shaped to surround a tubular stationary shaft of the spin to chuck engaged with the rotary shaft; a sensing unit which senses whether or not the tubular stationary shaft of the spin chuck is inserted into the shaft guide to a predetermined height; a control unit which determines whether or not the spin chuck has been assembled normally from a signal sensed by the sensing unit; and a notifying means which is controlled by the control unit to allow a user to recognize an assembled state of the spin chuck.