System for preventing improper insertion of FOUP door into FOUP

A pod for storing and transporting articles comprising:

• a pod shell having an opening and a sealing surface surrounding said opening, and further having multiple latch engagement slots configured such that at least one latch engagement slot is recessed further from said sealing surface than the remaining latch engagement slots, at least one said latch engagement slot extendings through said pod shell at a different angle than the remaining said latch engagement slots;
• and
• a pod door capable of forming a seal with said sealing surface, said pod door having a latch mechanism that includes fingers adapted to engage said latch engagement slots when said fingers are aligned with said latch engagement slots.

A for storing and transporting workpieces in an environment isolated from ambient atmospheric conditions, comprising:

• a container shell having an opening and a sealing surface surrounding said opening, said opening defining a substantially vertical plane, and further having multiple latch engagement slots configured such that at least one latch engagement slot is a different shape than the remaining said latch engagement slots, said latch engagement slots being recessed from said substantially vertical plane, at least one latch engagement slot being recessed further from said substantially vertical plane than the remaining said latch engagement slots;
• and
• a container door capable of forming a seal with said sealing surface, said container door having means for coupling said container door with said container shell by engaging said latch engagement slots.

A pod for storing and transporting articles, comprising:

• a pod shell having an opening, said pod shell having single latch engagement slots and double latch engagement slots;
• and
• a pod door capable of forming a seal with said pod shell, said pod door having a latch mechanism that includes a first latch plate with o/ne finger able to engage said single latch engagement slot when said finger is aligned with said single latch engagement slot, and a second latch plate with two fingers able to engage said double latch engagement slot when said fingers are aligned with said double latch engagement slots.

A wafer container comprising:

• an enclosure portion having a plurality of wafer shelves therein adapted for holding a plurality of wafers in a horizontal spaced apart position relative to each other, said enclosure portion having a door frame defining an opening, said door frame having a plurality of latch engagement recesses defined therein;
• and
• a door positionable in said door frame to sealingly close said opening, said door positionable in said door frame in a favored orientation and at least one disfavored orientation, said door having at least one selectively operable latch mechanism including a plurality of latch plates for engaging said latch engagement recesses, said latch plates and said latch engagement recesses being shaped and positioned so that said latch plates are engagable in said latch engagement recesses when said door is positioned in said door frame in said favored orientation and so that said latch plates are not engageable in said latch engagement recesses when said door is positioned in said at least one disfavored orientation.