Directional deposition in etch chamber
Methods for forming a vertical growth mask for use in etching applications are described herein. Disclosed embodiments include introducing a tungsten-containing deposition precursor and one or more carrier gases while igniting a plasma to deposit tungsten selectively on field regions of positive features of a patterned etch mask without substantial deposition on sidewalls of the positive features or on an exposed surface of a target layer underlying the patterned etch mask.
1. A method comprising:
providing a semiconductor substrate comprising a carbon-containing target layer, an anti-reflective layer, and a patterned photoresist;
patterning the anti-reflective layer to form a patterned anti-reflective mask;
exposing the semiconductor substrate to a tungsten-containing precursor and igniting a plasma under conditions to selectively deposit a tungsten-containing mask to form a patterned tungsten-containing mask on field regions of the patterned anti-reflective mask; and
patterning the carbon-containing target layer using the patterned anti-reflective mask and patterned tungsten-containing mask.
2. The method of claim 1 , wherein the formation of the patterned tungsten-containing mask and the patterning the carbon-containing target layer are performed simultaneously.
3. The method of claim 1 , wherein the formation of the patterned tungsten-containing mask and the patterning the carbon-containing target layer are performed in a cycle.
4. The method of claim 1 , wherein the depositing of the tungsten-containing mask comprises using one or more cycles of (i) a pulse of a first gas and (ii) a pulse of a mixture of second and third gases.
5. The method of claim 4 , wherein the first gas comprises the tungsten-containing precursor, and the mixture of second and third gases comprises a mixture of argon and hydrogen gas.
6. The method of claim 4 , further comprising selecting a quantity of the one or more cycles based on a duration of the pulse of the first gas, a duration of the pulse of the mixture of second and third gases, a desired thickness of the tungsten-containing mask, or a combination thereof.
7. A method comprising:
providing a semiconductor substrate comprising a carbon-containing target layer and a patterned etch mask having a first critical dimension;
exposing the semiconductor substrate to plasma generated using a plasma power between about 100W and about 500W from one or more pulses of a tungsten-containing precursor and one or more pulses of a mixture of argon and hydrogen gas at a substrate temperature less than about 160° C. to form tungsten material having a second critical dimension on the patterned etch mask, and
patterning the carbon-containing target layer using the patterned etch mask and the tungsten material;
wherein the second critical dimension is within 150% of the first critical dimension.
8. The method of claim 7 , wherein the one or more pulses of the mixture of argon and hydrogen gas comprise a duration of between about 100 milliseconds and about 10 seconds.
9. The method of claim 7 , wherein the one or more pulses of a tungsten-containing precursor comprise a duration of between about 100 milliseconds and about 10 seconds.
10. The method of claim 7 , wherein the formation of the tungsten material and the patterning of the carbon-containing target layer are performed simultaneously.
11. The method of claim 7 , wherein the formation of the tungsten material and the patterning of the carbon-containing target layer are performed in a cycle.
12. The method of claim 7 , wherein the one or more pulses of the tungsten-containing precursor and the one or more pulses of the mixture of argon and hydrogen gas comprise a plurality of alternating pulses of the tungsten-containing precursor and the mixture of argon and hydrogen gas.
13. The method of claim 12 , wherein the plurality of alternating pulses comprise a quantity of cycles selected based on a duration of each of the plurality of alternating pulses of the tungsten-containing precursor and the mixture of argon and hydrogen gas, a desired thickness of the tungsten material, or a combination thereof.
14. The method of claim 13 , wherein the quantity of cycles is between about 3 cycles and about 20 cycles.