Method and apparatus for non-invasive measurement and analysis of semiconductor process parameters

Abstract

A RF sensor for sensing and analyzing parameters of plasma processing. The RF sensor is provided with a plasma processing tool and an antenna for receiving RF energy radiated from the plasma processing tool. The antenna is located proximate to the plasma processing tool so as to be non-invasive. Additionally, the RF sensor may be configured for wideband reception of multiple harmonics of the RF energy that is radiated from the plasma processing tool. Further, the RF sensor may be coupled to a high pass filter and a processor for processing the received RF energy. Additionally, the antenna may be located within an enclosure with absorbers to reduce the interference experienced by the RF sensor. Additionally, a tool control may be coupled to the processor to provided to adjust and maintain various parameters of plasma processing according to the information provided by the received RF energy.

1 . A system for sensing parameters of plasma processing, said system comprising: 
 a plasma processing tool;    an enclosure placed proximate to said plasma processing tool;    an antenna, located inside said enclosure, for receiving RF energy radiated from said plasma processing tool; and    a processor coupled to said antenna for processing said RF energy received by said antenna.    
   
   
       2 . The system of  claim 1 , wherein said enclosure is attached to said plasma processing tool.  
   
   
       3 . The system of  claim 1 , further comprising: 
 at least one absorber provided with said enclosure for absorbing RF energy.    
   
   
       4 . The system of  claim 3 , wherein said enclosure has at least one surface adjacent to a surface of said plasma processing tool, and said at least one surface and said surface of said plasma processing tool are configured to pass RF energy.  
   
   
       5 . The system of  claim 1 , wherein said enclosure and said tool are adjacent and define an opening therebetween.  
   
   
       6 . The system of  claim 4 , wherein said at least one absorber is located to prevent absorption of RF energy passing through said at least one surface of said enclosure adjacent to said plasma processing tool.  
   
   
       7 . The system of  claim 3 , wherein a first absorber is configured to absorb a fundamental frequency of said RF energy and a second absorber is configured to absorb a harmonic frequency of said RF energy.  
   
   
       8 . The system of  claim 3 , wherein said enclosure is rectangular and said absorbers are provided on all sides of said enclosure except a side located proximate to said plasma processing tool.