Magnetic seal for wafer containers

Abstract

A wafer container with the door frame has a magnetic seal that encircles the periphery of the door and has a flexible portion extending laterally outwardly to engage a corresponding magnetic seal around the periphery of the door. Thus the door and container can be provided with a seal that is strong enough to exclude contaminants and also allows easy removal of the door either manually or by a robotic arm.

1 . A substrate container, the container comprising: 
 an enclosure portion having an open side with a first periphery, a door frame therearound, said door frame having a first sealing part extending therearound; substrate supports within the enclosure portion; and    a door having a second periphery sized for engagement with said door frame, said door having a second sealing part extending around the second periphery for sealingly engaging the first sealing part, the door comprising a latch mechanism for latching onto the door frame;    one of the first sealing part and second sealing part comprising a magnet, the other of the first sealing part and second sealing part comprising a magnetically attractable material whereby force pulls together in a sealing engagement said first sealing part and said second sealing part.    
   
   
       2 . The substrate container of  claim 1 , wherein the first sealing part includes an elastomeric overmolded ferrous or steel strip and the second sealing part includes a magnet overmolded with elastomeric material.  
   
   
       3 . The substrate container of  claim 2 , wherein the second sealing parts comprises an extendible portion formed of the elastomeric material, the second part having an extended position and a retracted position.  
   
   
       4 . The substrate container of  claim 1 , wherein one of the first and second sealing portions has an extendible portion and said one has a position and an extended position a and wherein when the first part and second part are in the sealing engagement the one is in its extended position.  
   
   
       5 . The substrate container of  claim 1 , wherein the door and container portion have a hard stop with the door in the door frame and wherein said seating position the first and second parts are sealingly engaged and the second part is in the extended position.  
   
   
       6 . The substrate container of  claim 3 , wherein said door frame has a groove and wherein the first sealing part comprises a magnetic gasket and said magnetic gasket is disposed in said groove.  
   
   
       7 . The substrate container of  claim 1 , wherein at least one of the first and second sealing parts includes a plastic magnet.  
   
   
       8 . The substrate container of  claim 1 , wherein at least one of the first and second sealing parts includes a series of discrete overmolded magnets spaced at intervals around one of the first or second peripheries.  
   
   
       9 . The substrate container of  claim 8 , wherein the other of the first and second sealing parts includes a series of discrete overmolded metallic pieces around the first or second peripheries.  
   
   
       10 . A sealable container for containing wafers, the container comprising: 
 an enclosure with a door frame defining an open side, wherein said door frame includes; 
 a rectangular outwardly facing flat and radially extending sealing surface and a first elastomeric magnetic seal extending around said door frame; and  
   a door comprising: 
 an interior facing surface;  
 a parallel exterior facing surface;  
 four side surfaces proximate the interior facing side and the exterior facing side;  
 a groove inset in the four sides and extending around said door; and  
 a second elastomeric magnetic seal in the groove and extending around the door, the second magnetic seal, in cross section, having an inset portion positioned in the groove and an exposed portion extending outwardly therefrom, the exposed portion having a cross section with a base portion, a flexible portion, and a sealing surface in substantial alignment in a radial direction, the sealing surface protruding substantially axially toward the enclosure portion and the exposed door frame as the door is inserted into and removed from the door frame by moving axially in a direction transverse to the greater dimension of the second elastomeric seal.  
   
   
   
       11 . The substrate container of  claim 10 , wherein the first magnetic seal includes an elastomeric overmolded metallic strip and the second magnetic seal includes an elastomeric overmolded magnet.  
   
   
       12 . The substrate container of  claim 10 , wherein at least one of the first and second magnetic seals is a plastic magnet.  
   
   
       13 . The substrate container of  claim 10 , further comprising a door latch for attaching said door to said enclosure.  
   
   
       14 . The substrate container of  claim 10 , wherein at least one of the first and second magnetic seals includes a series of discrete overmolded magnets spaced at intervals around the first or second peripheries.  
   
   
       15 . The substrate container of  claim 10 , wherein at least one of the first and second magnetic seals includes a series of discrete overmolded metallic strips around the first or second peripheries.  
   
   
       16 . A method for sealing wafer containers, the method comprising the following steps: 
 providing an enclosure defining a first periphery, said enclosure having a door frame around the first periphery, said door frame having a first magnetic gasket and a first door latch mechanism proximate the first periphery; and    providing a door defining a second periphery sized for engagement with said door frame, said door having a second magnetic gasket around the second periphery for sealingly engaging the first magnetic gasket and further having a second door latch mechanism proximate the second periphery for engaging the first latch mechanism; and    engaging the first latch mechanism with the second latch mechanism; and    sealingly engaging the first magnetic gasket with the second magnetic gasket.    
   
   
       17 . The method of  claim 16  wherein the first magnetic gasket includes an elastomeric overmolded metallic strip and the second magnetic gasket includes an elastomeric overmolded magnet.  
   
   
       18 . The method of  claim 16  wherein at least one of the first and second magnetic seals is a plastic magnet.  
   
   
       19 . The method of  claim 16 , wherein at least one of the first and second magnetic seals includes a series of discrete overmolded magnets spaced at intervals around the first or second peripheries.  
   
   
       20 . The method of  claim 16 , wherein at least one of the first and second magnetic seals includes a series of discrete overmolded metallic strips around the first or second peripheries.