| 摘要 |
In the case of storing an inclined wafer in a cassette, a robot hand recognizes the water, and can carry out the wafer without damage. The robot hand (51) is inserted inside the cassette (4a), enables to move in a direction of approaching the wafer (W4) by releasing the control of a twist motor by a control unit and freely rotating the robot hand (51). When an angle recognized by an encoder is changed by being in contact the robot hand (51) to the wafer (W4), the wafer (W4) stored inside the cassette (4a) is determined to be inclined. A slope of the wafer (W4) can be detected by detecting the rotation of the robot hand (51), thereby preventing the damage to the wafer (W4) by colliding the robot hand (51) with the wafer (W4). |
