Bell jar extraction tool method and apparatus for thin film photovoltaic materials

Abstract

An apparatus for extracting a bell jar chamber from a processing station of a thin film photovoltaic material is provided. The apparatus includes a rack fixture coupled to a robot loader. The rack fixture is configured to support the bell jar chamber to be moved using the robot loader in a horizontal direction and in a vertical direction. The apparatus further includes at least two support members configured within a vicinity of an upper region of the rack fixture.

What is claimed is: 
     
         1 . An apparatus for extracting a bell jar chamber from a processing station, the apparatus comprising:
 a rack fixture; and   at least two support members positioned proximate an outer surface of the rack fixture, wherein the at least two support members are at least partially characterized along an outer edge by an arcuate shape configured to support the bell jar chamber along an upper inner region.   
     
     
         2 . The apparatus of  claim 1 , further comprising polymeric material overlying each of the at least two support members. 
     
     
         3 . The apparatus of  claim 2 , wherein the polymeric material is selected from a rubber material, an O-ring, or a Delrin Acetal material, wherein the polymeric material is configured to cushion the arc length regions of the support members; wherein the bell jar chamber comprises a quartz material, the bell jar chamber having an axial length of about 200 cm and greater from an open end to a closed end, a diameter of 100 cm and greater, and a shell thickness of about 1.8 cm and greater, the bell jar chamber being characterized by an intrinsic factor of safety of about 7.0 based on Mohr-Coulomb failure theory applied for the quartz material. 
     
     
         4 . The apparatus of  claim 1 , wherein each of the at least two support members are positioned along the rack fixture at a distance from one another of less than or about 140 cm. 
     
     
         5 . The apparatus of  claim 1 , wherein each support member defines a trench within the outer edge characterized by an arcuate shape. 
     
     
         6 . The apparatus of  claim 5  wherein the trench is characterized by a dovetail shape. 
     
     
         7 . The apparatus of  claim 6 , further comprising an insert positioned between an inner edge of the trench and a gasket at least partially located within the trench. 
     
     
         8 . The apparatus of  claim 5  wherein a first end and a second end of the outer edge characterized by the arcuate shape comprises a corresponding included angle of about 90 degrees and greater. 
     
     
         9 . The apparatus of  claim 1  wherein the at least two support members comprise a first support member spaced from a second support member to balance the bell jar chamber about a center of gravity of the bell jar chamber. 
     
     
         10 . The apparatus of  claim 1  wherein the rack fixture is configured to support the bell jar chamber to maintain a stress level of the bell jar chamber to below a breakage stress of the bell jar chamber by a factor of safety, the factor of safety being defined as an inverse sum of a first ratio of an applied tensile stress over a tensile strength of chamber material and a second ratio of an applied compressive stress over a compressive strength of chamber material. 
     
     
         11 . A method for extracting a bell jar chamber, the method comprising:
 providing a rack fixture having at least two support members, each support member comprising an upper edge region;   inserting the rack fixture including the at least two support members from an open end horizontally into a bell jar chamber along an axial direction of the bell jar chamber;   interfacing the at least two support members with an inner region of the bell jar chamber; and   moving the bell jar chamber.   
     
     
         12 . The method of  claim 11  wherein providing the rack fixture comprises coupling the rack fixture to a robot loader configured to move horizontally and vertically. 
     
     
         13 . The method of  claim 11  wherein providing the rack fixture having at least two support members comprises disposing a first support member spaced from a second support member by a predetermined distance related at least to a center of gravity of the bell jar chamber. 
     
     
         14 . The method of  claim 11  wherein each of the at least two support members comprises a groove region formed from a first end to a second end along the upper edge region, the groove region being configured to seat a material for reducing stress level of the bell jar chamber around a contact region between the upper edge region of the two support members and an upper inner region of the bell jar chamber. 
     
     
         15 . The method of  claim 11  wherein inserting the rack fixture comprises positioning the two support members to respective positions that are substantially balanced relative to a center of gravity of the bell jar chamber and at least a predetermined distance away from the open end of the bell jar chamber. 
     
     
         16 . The method of  claim 15  wherein the predetermined distance comprises about 15% of an axial length of the bell jar chamber. 
     
     
         17 . A method for handling a chamber for manufacturing a photovoltaic device, the method comprising:
 inserting a rack fixture including at least two support members from an open end into the chamber along an axial direction;   raising the rack fixture to form a contact region between each of the two support members and an upper inner region of the chamber;   lifting the chamber; and   disposing the chamber to a processing station.   
     
     
         18 . The method of  claim 17  wherein the chamber comprises a quartz bell jar having a tubular shape with an open end and a closed end. 
     
     
         19 . The method of  claim 18  wherein each of the two support members is configured to have the contact region spread laterally with an arc length following the tubular shape of an inner region of the bell jar, the arc length corresponding to an included angle of 90 degrees and greater. 
     
     
         20 . The method of  claim 19  wherein the inner region of the bell jar is subjected to a contact force substantially smaller than an intrinsic stress strength of the quartz bell jar.