Plasma abatement of compounds containing heavy atoms
A plasma abatement process for abating effluent containing compounds from a processing chamber is described. A plasma abatement process takes gaseous foreline effluent from a processing chamber, such as a deposition chamber, and reacts the effluent within a plasma chamber placed in the foreline path. The plasma dissociates the compounds within the effluent, converting the effluent into more benign compounds. Abating reagents may assist in the abating of the compounds. The abatement process may be a volatizing or a condensing abatement process. Representative volatilizing abating reagents include, for example, CH 4 , H 2 O, H 2 , NF 3 , SF 6 , F 2 , HCl, HF, Cl 2 , and HBr. Representative condensing abating reagents include, for example, H 2 , H 2 O, O 2 , N 2 , O 3 , CO, CO 2 , NH 3 , N 2 O, CH 4 , and combinations thereof.
1. An apparatus for abating effluent from a processing chamber, comprising:
a plasma source coupled to a gas line of a deposition chamber, the plasma source comprising:
a first plate having an outer edge and an inner edge;
a second plate parallel to the first plate, wherein the second plate has an outer edge and an inner edge;
an inner wall disposed between the inner edges of the first and second plates, wherein the first plate and the second plate are concentric with the inner wall;
an outer wall disposed between the outer edges of the first and second plates, the first plate, the second plate, the inner wall and the outer wall defining a plasma region;
a first plurality of magnets disposed on the first plate; and
a second plurality of magnets disposed on the second plate; and
a reagent source positioned upstream of the plasma source, wherein the reagent source is coupled with the plasma source, and wherein the reagent source is operable to deliver an abating reagent to the plasma source.
2. The apparatus of claim 1 , wherein the inner wall is a hollow electrode coupling to an RF source.
3. The apparatus of claim 1 , wherein the outer wall is grounded.
4. The apparatus of claim 1 , further comprising:
a first insulating ring disposed adjacent to a first end of the inner wall; and
a second insulating ring disposed adjacent to a second end of the inner wall, wherein the first end is opposed to the second end.
5. The apparatus of claim 1 , further comprising:
a cooling plate coupled to the inner wall, the cooling plate has a cooling channel formed therein.
6. The apparatus of claim 1 , wherein the inner wall has a first surface facing the outer wall and a second surface opposite the first surface, wherein the first surface is curved and the second surface is linear.
7. The apparatus of claim 6 , wherein the first surface of the inner wall has a plurality of groves disposed thereon.
8. The apparatus of claim 7 , wherein each of the groves is a continuous trench.
9. The apparatus of claim 1 , wherein the abating reagent is selected from the group comprising BCl 3 , CCl 4 , SiCl 4 , NF 3 , SF 4 , SF 6 , SF 8 , a reducing compound, a halogenated etching compound, CH 4 , H 2 , F 2 , HCl, HF, Cl 2 , HBr, O 2 , N 2 , O 3 , CO, CO 2 , NH 3 , N 2 O, CH 4 , and combinations thereof.
10. The apparatus of claim 9 , wherein the abating reagent is CH 4 .
11. The apparatus of claim 9 , wherein the abating reagent is SF 6 .
12. An apparatus for abating effluent from a processing chamber, comprising:
a plasma source coupled to a gas line of a deposition chamber, the plasma source comprising:
a first plate having an outer edge and an inner edge;
a second plate parallel to the first plate, wherein the second plate has an outer edge and an inner edge;
an inner wall disposed between the inner edges of the first and second plates, wherein the first plate and the second plate are concentric with the inner wall;
an outer wall disposed between the outer edges of the first and second plates, the first plate, the second plate, the inner wall and the outer wall defining a plasma region therein;
a first magnet disposed on the first plate; and
a second magnet disposed on the second plate; and
a reagent source positioned upstream of the plasma source, wherein the reagent source is coupled with the plasma source, and wherein the reagent source is operable to deliver an abating reagent to the plasma source.