| 摘要 |
<p>PURPOSE:To inspect distortion of a wafer cassette easily and in a short time by judging whether a gauge plate which is provided with the reference size of a wafer and whose flatness is within a permissible range can be housed inside the groove of the wafer cassette or not. CONSTITUTION:A wafer cassette 6 is placed on the prescribed position of a specimen stand 2; after that, a pusher 5 is moved; a gauge plate 1 is inserted into grooves 4. When the grooves 4 are deformed or crooked, the gauge plate cannot be inserted into the grooves 4, the gauge plate 1 touches the deformed part of the grooves 4 and the wafer cassette 6 is slid on the specimen stand 2. Consequently, the wafer cassette 6 is brought close to a detector 3 and judged to be defective. When the deformation and the distortion of the grooves 4 are small, the gauge plate 1 is housed in the grooves 4 and stopped in a prescribed position. The pusher 5 is returned again to its original position.</p> |
