Systems and methods for selective metal compound removal
Exemplary etching methods may include flowing a fluorine-containing precursor and a hydrogen-containing precursor into a remote plasma region of a semiconductor processing chamber. The hydrogen-containing precursor may be flowed at a flow rate of at least 2:1 relative to the flow rate of the fluorine-containing precursor. The methods may include forming a plasma of the fluorine-containing precursor and the hydrogen-containing precursor to produce plasma effluents. The methods may include flowing the plasma effluents into a substrate processing region housing a substrate. The substrate may include an exposed region of a tantalum or titanium material and an exposed region of a silicon-containing material or a metal. The methods may include contacting the substrate with the plasma effluents. The methods may include removing the tantalum or titanium material selectively to the silicon-containing material or the metal.
1. An etching method comprising:
flowing a fluorine-containing precursor and a hydrogen-containing precursor into a remote plasma region of a semiconductor processing chamber, wherein the hydrogen-containing precursor is flowed at a flow rate of at least 2:1 relative to the flow rate of the fluorine-containing precursor;
forming a plasma of the fluorine-containing precursor and the hydrogen-containing precursor to produce plasma effluents;
flowing the plasma effluents into a substrate processing region housing a substrate, wherein the substrate comprises an exposed region of a tantalum or titanium material and an exposed region of a silicon-containing material;
contacting the substrate with the plasma effluents; and
removing the tantalum or titanium material selectively to the silicon-containing material, wherein the etching method is performed at a temperature greater than 500° C.
2. The etching method of claim 1 , wherein the tantalum or titanium material comprises tantalum or titanium metal or an oxide or nitride of tantalum or titanium.
3. The etching method of claim 1 , wherein the substrate further comprises an exposed region of a metal comprising tungsten, cobalt, or copper.
4. The etching method of claim 1 , wherein a plasma power is maintained at less than or about 1,000 W.
5. The etching method of claim 1 , wherein the etching method is performed at greater than or about 550° C and less than or about 800° C .
6. The etching method of claim 1 , wherein the etching method is performed at a pressure less than or about 10 Torr.
7. The etching method of claim 1 , further comprising:
a pre-treatment performed prior to flowing the fluorine-containing precursor, wherein the pre-treatment comprises contacting the substrate with a plasma comprising one or more of oxygen, hydrogen, water vapor, or nitrogen.
8. The etching method of claim 1 , further comprising
a post-treatment performed subsequent the etching method, wherein the post-treatment comprises contacting the substrate with a plasma comprising one or more of hydrogen, nitrogen, oxygen, or water vapor.
9. The etching method of claim 1 , further comprising:
removing the substrate from the semiconductor processing chamber, and
removing a residue from chamber walls of the semiconductor processing chamber.
10. The etching method of claim 9 , wherein removing the residue comprises:
providing a chlorine-containing precursor or plasma effluent or a bromine-containing precursor or plasma effluent.
11. The etching method of claim 1 , wherein the tantalum or titanium material is removed at a rate of at least 20:1 relative to the silicon-containing material.
12. The etching method of claim 1 , wherein the hydrogen-containing precursor is flowed at a flow rate of at least 10:1 relative to the flow rate of the fluorine-containing precursor.
13. An etching method comprising:
forming a plasma of a treatment precursor comprising one or more of oxygen, hydrogen, or nitrogen to produce treatment plasma effluents;
flowing the treatment plasma effluents into a substrate processing region of a semiconductor processing chamber;
contacting a substrate housed in the substrate processing region with the treatment plasma effluents, wherein the substrate defines an exposed region of a tantalum or titanium material and an exposed region of a tungsten, cobalt, or copper;
removing a carbon-containing material from a surface of the tantalum or titanium material;
forming a plasma of a fluorine-containing precursor and a hydrogen-containing precursor, wherein the hydrogen-containing precursor is flowed at a rate relative to the fluorine-containing precursor of greater than or about 2:1;
contacting the substrate with plasma effluents;
removing the tantalum or titanium material; and
subsequent to removing the tantalum or titanium material and prior to removing the substrate from the semiconductor processing chamber, contacting the substrate with a plasma comprising hydrogen, wherein the etching method is performed at a temperature greater than or about 500° C.
14. The etching method of claim 13 , wherein a plasma power during the forming of the plasma of the fluorine-containing precursor is maintained at less than or about 1,000 W.
15. The etching method of claim 13 , wherein the etching method is performed at greater than or about 550° C and less than or about 800° C.
16. The etching method of claim 13 , wherein the etching method is performed at a pressure less than or about 10 Torr.
17. The etching method of claim 13 , further comprising:
removing the substrate from the semiconductor processing chamber, and
removing a residue from chamber walls of the semiconductor processing chamber.
18. An etching method comprising:
flowing a fluorine-containing precursor and a hydrogen-containing precursor into a remote plasma region of a semiconductor processing chamber, wherein the hydrogen-containing precursor is flowed at a flow rate of at least 2:1 relative to the flow rate of the fluorine-containing precursor;
forming a plasma of the fluorine-containing precursor and the hydrogen-containing precursor to produce plasma effluents;
flowing the plasma effluents into a substrate processing region housing a substrate, wherein the substrate comprises an exposed region of a tantalum or titanium material and an exposed region of a silicon-containing material;
contacting the substrate with the plasma effluents;
removing the tantalum or titanium material selectively to the silicon-containing material;
forming a plasma of a treatment precursor comprising hydrogen to produce treatment plasma effluents; and
contacting the substrate with the treatment plasma effluents, wherein the etching method is performed at a temperature greater than 500° C.
19. The etching method of claim 18 , wherein the treatment plasma effluents are configured to remove residual fluorine from one or more of the substrate or the semiconductor processing chamber.
20. The etching method of claim 18 , further comprising:
removing the substrate from the semiconductor processing chamber, and
removing a residue from chamber walls of the semiconductor processing chamber with a chlorine-containing precursor.