Faraday Shield Having Plasma Density Decoupling Structure Between TCP Coil Zones

Abstract

A Faraday shield and a plasma processing chamber incorporating the Faraday shield is are provided. The plasma chamber includes an electrostatic chuck for receiving a substrate, a dielectric window connected to a top portion of the chamber, the dielectric window disposed over the electrostatic chuck, and a Faraday shield. The Faraday shield is disposed inside of the chamber and defined between the electrostatic chuck and the dielectric window. The Faraday shield includes an inner zone having an inner radius range that includes a first and second plurality of slots and an outer zone having an outer radius range that includes a third plurality of slots. The inner zone is adjacent to the outer zone. The Faraday shield also includes a band ring separating the inner zone and the outer zone, such that the first and second plurality of slots do not connect with the third plurality of slots.

What is claimed is: 
     
         1 . A plasma processing system, comprising:
 a chamber body having a support for receiving a substrate;   a pinnacle that surrounds a top portion of the chamber body;   a Faraday shield disposed over the pinnacle, such that the Faraday shield faces the support, the Faraday shield being electrically grounded; and   a dielectric window disposed over the Faraday shield;   the Faraday shield has a circular plate structure that includes,
 a first zone having a first radius range that includes first zone slots; 
 a second zone having a second radius range that includes second zone slots, the first zone being adjacent to the second zone; and 
 a band ring separating the first zone and the second zone, such that openings of the first and second zone slots do not connect, the band ring is part of the circular plate structure and the band ring is configured to decouple magnetic flux generation, and the first and second zone slots are arranged to extend out radially from a center of the circular plate structure. 
   
     
     
         2 . The plasma processing system of  claim 1 , further comprising,
 a transformer coupled plasma (TCP) coil having a substantially flat coil distribution being disposed over the dielectric window.   
     
     
         3 . The plasma processing system of  claim 2 , wherein the TCP coil is defined from an inner coil and an outer coil, the inner coil is disposed over the first zone slots and the outer coil is disposed over the second zone slots. 
     
     
         4 . The plasma processing system of  claim 1 , wherein the circular plate structure further comprises,
 a third zone having a third radius range that includes third zone slots; and   an outer ring band disposed in the circular plate structure between the second zone and third zone, the band ring being an inner ring band.   
     
     
         5 . The plasma processing system of  claim 4 , further comprising,
 a transformer coupled plasma (TCP) coil having a substantially flat coil distribution being disposed over the dielectric window, the TCP coil is defined from an inner coil, a middle coil, and an outer coil, the inner coil is disposed over the first zone slots, the middle coil is disposed over the second zone slots, and the outer coil is disposed over the third zone slots.   
     
     
         6 . The plasma processing system as recited in  claim 3 , wherein the inner coil and the outer coil are connected to a tuning circuit, the tuning circuit being configured adjust magnetic flux imparted through either or both of the first zone and the second zone of the Faraday shield. 
     
     
         7 . The plasma processing system as recited in  claim 5 , wherein the inner coil, the middle coil, and the outer coil are connected to a tuning circuit, the tuning circuit being configured adjust magnetic flux imparted through either one or each of the first zone, the second zone, and the third zone of the Faraday shield. 
     
     
         8 . The plasma processing system as recited in  claim 1 , wherein each one of the slots are defined from a chevron shaped groove. 
     
     
         9 . The plasma processing system as recited in  claim 8 , wherein the chevron shaped groove does not include a line of sight between respective sides of the Faraday shield. 
     
     
         10 . The plasma processing system as recited in  claim 1 , wherein the circular plate structure has a center hole. 
     
     
         11 . The plasma processing system as recited in  claim 1 , wherein the circular plate structure is defined from stainless steel, hastalloy or titanium. 
     
     
         12 . The plasma processing system as recited in  claim 11 , wherein the circular plate structure is passivated or coated with one of Y2O3, or CeO2, or TiN. 
     
     
         13 . A Faraday shield for a chamber used to process substrates, comprising:
 a circular plate structure having a center hole, the circular plate structure being substantially flat and configured to be disposed inside the chamber and below a dielectric window, the circular plate structure including,
 a first zone having a first radius range that includes first zone slots; 
 a second zone having a second radius range that includes second zone slots, the first zone being adjacent to the second zone; and 
 a band ring separating the first zone and the second zone, such that openings of the first and second zone slots do not connect, the band ring is part of the circular plate structure and the band ring is configured to decouple magnetic flux generation, and the first and second zone slots are arranged to extend out radially from a center of the circular plate structure. 
   
     
     
         14 . The Faraday shield of  claim 13 , wherein the circular plate structure further comprises,
 a third zone having a third radius range that includes third zone slots, wherein the first zone is an inner zone, the second zone is a middle zone, and the third zone is an outer zone, and wherein an outer ring band is disposed in the circular plate structure between the middle zone and the outer zone, the band ring being an inner ring band.   
     
     
         15 . The Faraday shield of  claim 14 , wherein the chamber includes
 a dielectric window disposed over the Faraday shield; and   a transformer coupled plasma (TCP) coil having a substantially flat coil distribution being disposed over the dielectric window, the TCP coil is defined from an inner coil, a middle coil, and an outer coil, the inner coil is disposed over the first zone slots, the middle coil is disposed over the second zone slots, and the outer coil is disposed over the third zone slots.   
     
     
         16 . The Faraday shield of  claim 13 , wherein the chamber includes,
 a dielectric window disposed over the Faraday shield; and   a transformer coupled plasma (TCP) coil having a substantially flat coil distribution being disposed over the dielectric window, the TCP coil is defined from an inner coil and an outer coil, the inner coil is disposed over the first zone slots and the outer coil is disposed over the second zone slots.   
     
     
         17 . The Faraday shield of  claim 13 , wherein the first zone slots and second zone slots are respectively arranged to extend out radially from a center of the circular plate structure and each slot is defined from a chevron groove. 
     
     
         18 . The Faraday shield of  claim 13 , wherein the circular plate structure is electrically grounded. 
     
     
         19 . The Faraday shield of  claim 18 , wherein the chevron shaped groove does not include a line of sight between respective sides of the Faraday shield. 
     
     
         20 . The Faraday shield of  claim 19 , wherein the circular plate structure is defined from stainless steel, hastalloy or titanium and is passivated or coated with one of Y2O3, or CeO2, or TiN.