Sealable transportable container having a particle filtering system

DETAILED DESCRIPTION The present invention is a transportable container which provides a clean environment for articles to be processed and which employs an active filtering system in localized areas to facilitate cleaning of the container and surrounding environments.
The container is used particularly in connection with semiconductor processing equipment which also provides a clean environment and which can be cleaned locally as well.
The container is also used to store articles before and after processing.
The container is adapted to receive a holder such as a wafer cassette holder for holding one or more articles such as semiconductor wafers.
It is a general object of this invention to provide a sealable transportable container in which the interior environment may be actively filtered as desired.
It is a further object of this invention to provide a sealable transportable container which is cleaned by alternatively pressurizing and evacuating the container through filter means.
It is a further object of this invention to provide a transportable container in which air may be circulated throughout the interior of the container without opening the container.
It is a further object of this invention to provide a port plate having an injector/extractor which has localized intelligence such that it can be actuated to either pressurize or evacuate at appropriate times.
It is a further object of this invention to provide a sealable transportable container as set forth above which includes means for sensing the quality and pressure of the interior space of the container.
It is a further object of this invention to provide a transportable container as set forth above which enhances the SMIF still air concept by matching environments as the wafers are transferred from one location to another.
In a first embodiment of this invention, the transportable container is used with processing equipment having a port plate and a port door sealably mating to the port plate, the container comprises a box defining an interior space for containing articles, such as semiconductor wafers