| 摘要 |
PURPOSE:To always hold a wafer cassette housing box in a dust-free state by providing a fan and a dust removing filter in an upper part in the box having a solar cell on an outer wall and disposing a cylinder opened at the upper and lower parts for containing a wafer cassette to generate an air convection from the inside of the cylinder toward an outside. CONSTITUTION:When a motor 32 to which electric power is supplied from a solar cell 3 rotates a fan 10, air in a box 7 is sucked from the upper part of a fan, and dusts in the air is filtered through a filter 12. Cleaned air is fed between a wafer 40 and a wafer cassette 14 in a wafer cassette housing space 16 through a lower opening 28a, and sucked from an air gap 24 to an upper part. The air is then fed through an upper opening 28b of the cylinder and again blown up by the fan 10 toward the filter 12. The air convection is continued without stop during the period that a light is being applied to the solar cell. Thus, no foreign material is adhered to the wafer while the wafer housed in the cassette is being moved or stocked. |
