Plasma Generator Apparatus

Abstract

Embodiments of a plasma generator apparatus for ashing a work piece are provided. The apparatus includes a container adapted for continuous gas flow there through from an inlet end to an outlet end thereof. The container is fabricated of a dielectric material and adapted for ionization therein of a portion of at least one component of gas flowing therethrough. A gas flow distributor is configured to direct gas flow to a region within the container and a coil surrounds at least a portion of side walls of the container adjacent the region of the container to which the gas flow distributor directs gas flow. A radio frequency generator is coupled to the coil.

1 . A plasma generator apparatus for ashing a work piece, the apparatus comprising:
 (a) a container adapted for continuous gas flow there through from an inlet end to an outlet end thereof, the container comprising a dielectric material and further adapted for ionization of a portion of at least one component of gas flowing therethrough;   (b) a gas flow distributor configured to direct gas flow to a region within the container;   (c) a coil surrounding at least a portion of side walls of the container, the portion of the side walls adjacent the region of the container to which the gas flow distributor directs gas flow; and   (d) a radio frequency generator coupled to the coil.   
   
   
       2 . The apparatus of  claim 1 , further comprising a gas diffuser at an outlet of the container. 
   
   
       3 . The apparatus of  claim 1 , wherein the container is cylindrical and the gas flow distributor comprises a circular baffle plate axially centered in a cylindrical container to direct gas flow towards side walls of the container. 
   
   
       4 . The apparatus of  claim 1 , wherein the container comprises a cylindrical lower portion capped with a domed or conical upper portion. 
   
   
       5 . The apparatus of  claim 4 , wherein the gas flow distributor comprises a nozzle located proximate an apex of the domed or conical upper portion, the nozzle directing gas flow along inner walls of the domed or conical upper portion. 
   
   
       6 . The apparatus of  claim 5 , further comprising a Faraday shield interposed between the coil and the at least a portion of the side walls of the container. 
   
   
       7 . The apparatus of  claim 5 , wherein the nozzle comprises a hemisphere with a plurality of through holes, the through holes directing gas flowing therethrough to at least a portion of the side walls surrounded by the coil. 
   
   
       8 . The apparatus of  claim 5 , wherein the nozzle comprises a tube extending axially into the container, the tube comprising a plurality of through holes in a side wall thereof, the through holes directing gas flow to the portion of the side walls of the container surrounded by the coil. 
   
   
       9 . The apparatus of  claim 1 , wherein the coil comprises a symmetrical coil. 
   
   
       10 . The apparatus of  claim 9 , wherein the symmetrical coil comprises at least about 2 segments. 
   
   
       11 . The apparatus of  claim 1 , wherein a largest dimension of the container, transverse to gas flow in the container, approximates a dimension of a surface of a work piece, the surface to be treated by the apparatus. 
   
   
       12 . An apparatus for ashing a work piece, the apparatus comprising:
 (a) a container configured for flow there through from an inlet end to an outlet end, the container comprising side walls adapted for ionization of a portion of at least one component of the gas flowing through the container;   (b) a gas flow distributor adapted to direct gas flow to a region within the container;   (c) a segmented coil surrounding at least a portion of side walls the container, the portion adjacent the region of the container to which the gas flow distributor directs gas flow, the segmented coil free of any Faraday shield interposed between the segmented coil and the portion of the side walls;   (d) a radio frequency generator coupled to the segmented coil; and   (e) a diffusion plate at an exit end of the container to direct gas flow onto a surface of a work piece to be ashed.   
   
   
       13 . The apparatus of  claim 12 , wherein the container is cylindrical and the gas flow distributor comprises a circular baffle plate axially centered in a cylindrical container to direct gas flow towards side walls of the container. 
   
   
       14 . The apparatus of  claim 12 , wherein the container comprises a cylindrical lower portion capped with a domed or conical upper portion. 
   
   
       15 . The apparatus of  claim 12 , wherein the gas flow distributor comprises a nozzle located proximate an apex of the domed or conical upper portion, the gas flow distributor directing gas flow along inner walls of the domed or conical upper portion to the portion of the side walls of the container surrounded by the segmented coil. 
   
   
       16 . The apparatus of  claim 14 , wherein the container and the dome-shaped or cone-shaped upper portion are comprised of quartz. 
   
   
       17 . The apparatus of  claim 15 , wherein the gas flow distributor comprises a hemispherical nozzle with a plurality of through holes. 
   
   
       18 . The apparatus of  claim 15  wherein the gas flow distributor comprises a tube extending axially into the container, the tube comprising a plurality of through holes in a side wall thereof, the through holes directing gas flow along inner walls of the domed or conical upper portion to the portion of the side walls of the container surrounded by the segmented coil. 
   
   
       19 . The apparatus of  claim 12 , wherein the segmented coil comprises at least 2 segments. 
   
   
       20 . A plasma generator apparatus for ashing a work piece, the apparatus comprising:
 (a) a container of larger diameter configured for continuous gas flow there through from an inlet end to an outlet end, the container comprising side walls of a dielectric material adapted for containing charged particles produced by radio frequency discharge into a gas, the container having a domed-shaped or cone-shaped upper portion;   (b) a gas flow distributor proximate the dome-shaped or cone-shaped upper portion of the container, the gas flow distributor adapted to direct gas flow to a region within the container;   (c) a diffusion plate proximate an outlet end of the container to direct gas flow from inside the container onto a surface of a work piece to be treated;   (d) a symmetrical coil comprising at least 2 segments, the symmetrical coil surrounding at least a portion of the side walls of the container, the portion of the side walls adjacent the region within the container to which the gas flow distributor directs gas flow; and   (e) a radio frequency generator coupled to the symmetrical coil.