| 摘要 |
PROBLEM TO BE SOLVED: To carry different sizes of substrates of semiconductor wafers without exchanging a carrier case by providing a plurality of retractable arms and by using them appropriately according to the different sizes of the substrates. SOLUTION: First and second retractable arms 30, 31 are rotatably attached to the tip parts of intermediate arms 28, 29 by third shafts 36, 37 respectively. The first and the second retractable arms 30, 31 have different thickness from each other and are appropriately used for different sizes of substrates, semiconductor wafers of 8 in. or less (6-8 in.) and semiconductor wafers exceeding 8 in. (12 in.) respectively. That is to say, the first retractable arm 30 is formed thinner in thickness than that of the second retractable arm 31 so that it is so set to be used appropriately that the smaller semiconductor wafers 8 in. or less are carried by the thinner first retractable arm 30, while the larger semiconductors 12 in. are carried by the thicker second retractable arm 31. |
