| 摘要 |
PROBLEM TO BE SOLVED: To prevent damage to a wafer when it is popped out from a cassette due to a positional shift by detecting it in an apparatus for attaching/detaching a cover of the cassette for accommodating the wafer. SOLUTION: The apparatus for attaching/detaching the cassette cover comprises a shielding door 30, capable of opening/closing an opening 11 faced by the cover 3 of the cassette 1 for accommodating the wafer, and capable of holding the cover, and driving mechanisms 40, 80 for moving the shielding door 30, while it holds the cover 3, forward/backward and upward/downward to attach/detach the cover 3 and the shielding door 30. A reflection type optical sensor 90 for projecting light in the direction nearly orthogonal to the main surface of the wafer is provided in the region of the opening 11. Thus, even if the wafer is transparent, the positional shift thereof can surely be detected so that the damage, etc., thereto can be prevented. COPYRIGHT: (C)2003,JPO |
