Handling of stacked substrates

Abstract

A pneumatic device for transporting a substrate during a manufacturing operation is described. The pneumatic device can include multiple suction assemblies for securely coupling the substrate to the pneumatic device. The vertical position of the suction assemblies can be varied so that when vacuum is applied through the suction assemblies to the substrate, the substrate is in a bent configuration when secured to the pneumatic device. When the pneumatic device is used to lift the substrate off a stack of other substrates, the bending of the substrate reduces the surface area contact and likelihood of inadvertently removing additional substrates from the stack of substrates.

What is claimed is: 
     
         1 . A pneumatic device, comprising:
 a support structure; and   a plurality of spring-loaded suction assemblies coupled to the support structure, the plurality of spring-loaded suction assemblies comprising:
 a first group of two or more spring-loaded suction assemblies extending a first distance from a surface of the support structure, and 
 a second group of one or more spring-loaded suction assemblies extending a second distance from the surface of the support structure, the second distance being greater than the first distance. 
   
     
     
         2 . The pneumatic device of  claim 1 , wherein each spring-loaded suction assembly of the plurality of spring-loaded suction assemblies includes a suction cup at a distal end of the spring-loaded suction assembly. 
     
     
         3 . The pneumatic device of  claim 2 , wherein the suction cups associated with the first group have a different design than the suction cups associated with the second group. 
     
     
         4 . The pneumatic device of  claim 1 , wherein the first group of two or more spring-loaded suction assemblies is arranged in a pattern that defines a polygon and wherein the second group of one or more spring-loaded suction assemblies is positioned within the polygon. 
     
     
         5 . The pneumatic device of  claim 1 , wherein the second group is arranged along a line and wherein each of the spring-loaded suction assemblies of the first group is offset from the line by substantially the same distance. 
     
     
         6 . The pneumatic device of  claim 1 , further comprising an air mover. 
     
     
         7 . The pneumatic device of  claim 6 , wherein each suction assembly of the first group of suction assemblies includes a pneumatic tube configured to receive positive or negative pressure from the air mover. 
     
     
         8 . The pneumatic device of  claim 1 , wherein each spring-loaded suction assembly comprises an internal spring. 
     
     
         9 . A method of lifting a substrate off of a stack of substrates, the method comprising:
 engaging a peripheral portion of the substrate with a first group of suction assemblies of a pneumatic device;   engaging a central portion of the substrate with a second group of suction assemblies of the pneumatic device;   bending the peripheral portion of the substrate away from the stack of substrates using the first group of suction assemblies while the second group of suction assemblies keeps the central portion of the substrate in contact with the stack of substrates; and   lifting the substrate off of the stack of substrates after bending the peripheral portion.   
     
     
         10 . The method of  claim 9 , wherein lifting the substrate comprises maintaining the bend in the substrate until the substrate is fully separated from the stack of substrates. 
     
     
         11 . The method of  claim 9 , wherein bending the peripheral portion of the substrate away from the stack of substrates comprises bending the substrate about a line of maximum deflection. 
     
     
         12 . The method of  claim 9 , wherein engaging the peripheral portion of the substrate comprises applying vacuum suction to the peripheral portion through the first group of suction assemblies. 
     
     
         13 . The method of  claim 12 , wherein engaging the central portion of the substrate does not include applying vacuum suction through the second group of suction assemblies. 
     
     
         14 . The method of  claim 12 , further comprising releasing the substrate from the pneumatic device by applying positive pressure to the substrate through the first group of suction assemblies. 
     
     
         15 . The method of  claim 9 , further comprising directing air between the substrate and the stack of substrates to help separate the substrate from the stack of substrates. 
     
     
         16 . The method of  claim 9 , wherein engaging the central portion of the substrate comprises positioning the second group of suction assemblies along a line of maximum deflection of the substrate. 
     
     
         17 . A pneumatic device, comprising:
 a support structure;   a plurality of suction assemblies coupled to the support structure;   a pushing assembly coupled to the support structure and extending farther away from the support structure than two or more of the plurality of suction assemblies; and   an air mover configured to drive air through and draw air into the plurality of suction assemblies.   
     
     
         18 . The pneumatic device of  claim 17 , wherein the pushing member is a spring-loaded suction assembly. 
     
     
         19 . The pneumatic device of  claim 17 , wherein the pushing assembly comprises a pushing member configured to engage a substrate with a convex surface. 
     
     
         20 . The pneumatic device of  claim 19 , wherein the first group of suction assemblies is arranged along a periphery of the substantially planar support structure.