Hollow anode plasma reactor and method

Abstract

The plasma processing apparatus includes a plasma chamber, a first electrode, a second electrode, and a plasma containment device. The plasma containment device has a plurality of slots and is electrically coupled to the first electrode. The containment device is configured to confine plasma within an inter-electrode volume while facilitating maximum process gas flow. When plasma is generated by applying electric fields to process gas within the inter-electrode volume, the containment device electrically confines the plasma to the inter-electrode volume without significantly restricting the flow of gas from the inter-electrode volume.

1 . An etch apparatus, comprising: 
 an electrical ground;    a plasma chamber coupled to the electrical ground;    a vacuum pump coupled to the plasma chamber;    a process gas source coupled to the plasma chamber;    a first electrode having a surface facing an interior of the plasma chamber;    a second electrode having a surface facing the interior of the plasma chamber that is proximate and substantially parallel to the first electrode;    a first power source coupled to the first electrode;    a second power source coupled to the second electrode;    a inter-electrode region disposed between the first and the second electrodes; and    a containment device enclosed within the plasma chamber and electrically coupled to the electrical ground, the containment device having a plurality of slots configured to facilitate gas flow between the inter-electrode region and the vacuum pump and having electrically conductive portions that substantially confine electric fields to the inter-electrode region.    
   
   
       2 . The etch apparatus of  claim 1  further comprising a vacuum line wherein the containment device comprises an annular device disposed adjacent to the second electrode separating the inter-electrode region from the vacuum line.  
   
   
       3 . The etch apparatus of  claim 1  wherein the slots of the containment device comprise substantially radial extending slots.  
   
   
       4 . The etch apparatus of  claim 1  wherein the slots of the containment device comprise substantially circumferential extending slots.  
   
   
       5 . The etch apparatus of  claim 1  wherein the containment device is configured to electrically confine a plasma to the inter-electrode region.  
   
   
       6 . The etch apparatus of  claim 1  wherein the containment device is mechanically coupled to the plasma chamber.  
   
   
       7 . The etch apparatus of  claim 1  wherein the containment device is configured to confine a plasma with a minimal gas flow restriction between the inter-electrode region and a remaining chamber volume.  
   
   
       8 . The etch apparatus of  claim 1  wherein the slots have a uniform cross section.  
   
   
       9 . The etch apparatus of  claim 1  wherein the slots have a non-uniform cross section.  
   
   
       10 . The etch apparatus of  claim 1  wherein the power sources comprise more than one radio frequency power supply.  
   
   
       11 . The etch apparatus of  claim 1  wherein the first and the second power sources comprises two radio frequency power supplies tuned to different radio frequencies.  
   
   
       12 . The etch apparatus of  claim 10  wherein the first power source is tuned to 27 megahertz and the second power source is tuned to 2 megahertz.  
   
   
       13 . A method of processing a substrate, comprising: 
 positioning a substrate on a substrate support in a plasma chamber, wherein a containment device is configured to electrically confine a plasma within an inter-electrode region above the substrate with substantially little resistance to a gas flow, the containment device enclosing the inter-electrode region above the substrate and being electrically coupled to a ground;    evacuating the plasma chamber through a vacuum pump;    providing process gases into the inter-electrode region through a supply line, the process gas being mechanically induced to move from the inter-electrode region through the containment device; and    energizing the process gas into a plasma by applying electric fields to the inter-electrode region.    
   
   
       14 . The method of  claim 13  wherein the containment device comprises an annular structure comprised of conductive walls with substantially vertical slots passing through the conductive walls.  
   
   
       15 . The method of  claim 13  further comprising etching a material from an exposed face of the substrate.  
   
   
       16 . The method of  claim 13  further comprising depositing a material onto an exposed face of the substrate.