| 摘要 |
PURPOSE:To prevent damage due to drop and to reduce a size by forming an attractive maintenance mechanism for holding the mask structure in a vacuum attraction state and providing th attractive face with positioning pins. CONSTITUTION:The attractive maintenance mechanism 18 for holding the mask structure 24 in a vacuum attraction state and providing the attractive face with the positioning pins 14, 15. Since the X ray mask structure 20 is held in a pending state and vacuum attraction is executed, even if vacuum pipings 19 or a vacuum pump are out of order and attractive force is lost, the structure 20 does not drop. |
