| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to recognize a wafer and ship the wafer without breakage thereof by a robot hand even if the wafer is accommodated in a cassette in an inclined state.SOLUTION: A robot hand 51 is so made as to enter into a cassette 4a and as to be freely rotatable by releasing control of a reversal motor by a control part, and is moved in a direction of approaching a wafer W4. When the robot hand 51 contacts the wafer W4 and an angle recognized by an encoder is changed, it is determined that the wafer W4 accommodated in the cassette 4a is inclined. Since it is possible to detect inclination of the wafer W4 by detecting rotation of the robot hand 51, breakage of the wafer W4 due to collision of the robot hand 51 with the wafer W4 can be prevented.SELECTED DRAWING: Figure 5 |
