Method and apparatus for selectively filtering residue from a processing chamber

Abstract

The processing system comprises a pump assembly, a bypass assembly, and a processing chamber, which together form a circulation path. The bypass assembly is configured so that in a first mode, a filter does not form part of the circulation path, and in a second mode the filter does form part of the circulation path. Thus, the processing system is placed in the first mode when a processing material circulated over the circulation path does not need to be filtered. The processing system is placed in the second mode when a processing material circulated over the circulation path must be filtered.

1 . An apparatus, comprising: 
 a processing chamber having a processing chamber inlet and a processing chamber outlet;    a recirculation subassembly having an inlet coupled to the processing chamber outlet and an outlet coupled to the processing chamber inlet, wherein the recirculation subassembly comprises a pump assembly and a bypass assembly coupled to the pump assembly, the bypass assembly comprising a first branch and a second branch; and    a controller coupled to the bypass assembly for switching the bypass assembly between a first mode and a second mode, wherein when the bypass circuit is in a first mode, a first path is establish through the recirculation subassembly that includes the pump assembly and the first branch, and when the bypass circuit is in a second mode, a second path is establish through the recirculation subassembly that includes the pump assembly and the second branch.    
   
   
       2 . The apparatus of  claim 1 , wherein the second branch contains a filter and the first branch contains a bypass line.  
   
   
       3 . The apparatus of  claim 1 , further comprising: 
 a fluid supply system coupled to the processing chamber, wherein a fluid contained in the fluid supply system is provided to the processing chamber and flows through the pump assembly, through the bypass assembly, and through the processing chamber.    
   
   
       4 . The apparatus of  claim 3 , wherein the pump assembly, the bypass assembly, and the processing chamber form a circulation loop.  
   
   
       5 . The apparatus of  claim 2 , wherein the bypass assembly comprises: 
 a first valve having an input, a first output, and a second output, the first output coupled to the filter the second output coupled to the bypass line; and    a second valve having a first input coupled to the filter, a second input coupled to the bypass line, and an output coupled to the processing chamber.    
   
   
       6 . The apparatus of  claim 1 , wherein the processing chamber is a supercritical processing chamber.  
   
   
       7 . The apparatus of  claim 3 , wherein the fluid comprises substantially pure CO 2 .  
   
   
       8 . An apparatus, comprising: 
 means for circulating a supercritical fluid over a substrate in a processing chamber, thereby creating a contaminated process fluid;    means for filtering the contaminated process fluid coupled to the means for circulating and the processing chamber;    means for bypassing coupled to the means for circulating and the processing chamber, wherein the means for bypassing comprises means for bypassing the means for filtering; and    means for controlling the means for bypassing, wherein when the means for bypassing is in a first mode, the means for circulating, the means for bypassing and the processing chamber define a first path containing a bypass line, and when the means for bypassing is in a second mode, the means for circulating, the means for filtering, and the processing chamber define a second path containing a filter.    
   
   
       9 . A method of circulating a first material and a second material in a processing system, comprising: 
 circulating the first material through a processing chamber over a first processing path through a recirculation subassembly during a first processing cycle; and    circulating a second material through the processing chamber over a second processing path through a recirculation subassembly during a second processing cycle, the second processing path different from the first processing path.    
   
   
       10 . The method of  claim 9 , wherein the second processing path comprises a filter and the first processing path comprises a bypass line.  
   
   
       11 . The method of  claim 9 , wherein one of the first processing cycle and the second processing cycle comprises supercritical processing.  
   
   
       12 . The method of  claim 9 , wherein the second material is carbon dioxide.  
   
   
       13 . The method of  claim 12 , wherein the carbon dioxide is in a supercritical state.  
   
   
       14 . The method of  claim 12 , wherein the second material further comprises a surfactant.  
   
   
       15 . The method of  claim 12 , wherein the second material further comprises an amide or an amine.