Segmented resonant antenna for radio frequency inductively coupled plasmas

Abstract

An ion shower system is disclosed and comprises a plasma source operable to generate source gas ions within a chamber. The plasma source further comprises a plurality of conductor segments and a plurality of capacitors, wherein the conductor segments are serially connected through the plurality of capacitors. The plasma source further comprises an antenna drive circuit coupled to the plurality of conductor segments that provides power to the conductor segments and capacitors at a predetermined frequency. The ion shower system also comprises a source gas inlet that provides a source gas to the chamber. The conductor segments, capacitors and antenna drive circuit cooperatively provide energy to charged particles in the chamber, thereby energizing the charged particles and generating a plasma comprising source gas ions and electrons within the chamber due to ionizing collisions between the energized charged particles and the source gas.

1 . An antenna, comprising: 
 a plurality of conductor segments; and    a plurality of capacitors, wherein the conductor segments are serially connected through the plurality of capacitors.    
     
     
         2 . The antenna of  claim 1 , further comprising an antenna drive circuit coupled to the plurality of conductor segments, and operable to provide power to the conductor segments at a predetermined frequency.  
     
     
         3 . The antenna of  claim 2 , wherein first and last conductor segments of the plurality of conductor segments form an input, and wherein the antenna drive circuit is coupled to the input.  
     
     
         4 . The antenna of  claim 2 , wherein the conductor segments have an inductive reactance associated therewith, and wherein the capacitors have a capacitive reactance associated therewith, and wherein one of the conductors and one of the capacitors form an antenna segment, wherein the inductive reactance and capacitive reactance of the antenna segment are equal at the predetermined frequency.  
     
     
         5 . The antenna of  claim 2 , wherein the plurality of conductor segments and plurality of capacitors form a resonant circuit at the predetermined frequency.  
     
     
         6 . The antenna of  claim 2 , wherein the antenna drive circuit comprises an oscillator circuit.  
     
     
         7 . The antenna of  claim 6 , wherein the oscillator circuit comprises a push-pull type oscillator circuit.  
     
     
         8 . The antenna of  claim 1 , wherein the plurality of conductor segments and capacitors are arranged azimuthally symmetric, wherein a non-uniform capacitive electrostatic field component along each conductor segment is repeated in an azimuthally symmetric fashion.  
     
     
         9 . An antenna, comprising: 
 a plurality of alternating conductors and capacitors serially coupled together to form a string of antenna segments; and    an antenna driver circuit coupled to the string of antenna segments, and operable to drive the string of antenna segments at a predetermined frequency.    
     
     
         10 . The antenna of  claim 9 , wherein the conductor segments have an inductive reactance associated therewith, and wherein the capacitors have a capacitive reactance associated therewith, and wherein one of the conductors and one of the capacitors form an antenna segment, wherein the inductive reactance and capacitive reactance of the antenna segment are equal at the predetermined frequency.  
     
     
         11 . The antenna of  claim 9 , wherein the plurality of conductor segments and plurality of capacitors form a resonant circuit at the predetermined frequency.  
     
     
         12 . The antenna of  claim 9 , wherein the string of antenna segments are arranged azimuthally symmetric, wherein a non-uniform capacitive electrostatic field component along each conductor segment is repeated in an azimuthally symmetric fashion.