Selective deposition of titanium films
Methods for selectively depositing on surfaces are disclosed. Some embodiments of the disclosure utilize an organometallic precursor that is substantially free of halogen and substantially free of oxygen. Deposition is performed to selectively deposit a metal film on a non-metallic surface over a metallic surface. Some embodiments of the disclosure relate to methods of gap filling.
1. A processing method comprising:
selectively depositing a titanium film on a non-metallic material on a substrate selectively relative to a metallic material on the substrate during a deposition process, the deposition process comprises co-flowing an organometallic precursor and a co-reactant over the substrate, the organometallic precursor substantially free of halogen and substantially free of oxygen and the organometallic precursor comprising a structure selected from
wherein R is hydrogen (H) or —(CH 2 ) n , R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen (H) and alkyl, R 5 , R 6 , and R 7 independently comprise an alkylamine, X and Y are independently selected from carbon (C) or nitrogen (N), and n is a number in a range of from 0 to 8.
2. The processing method of claim 1 , wherein the metallic material comprises metallic silicon (Si), metallic germanium (Ge), or SiGe alloy, each of which optionally being doped with phosphorus (P), arsenic (As), and/or boron (B), and the non-metallic material comprises silicon oxide (SiO x ), silicon nitride (SiN), or silicon oxide-nitride (SiON), each of which optionally being carbon-doped.
3. The processing method of claim 1 , wherein the titanium film is selectively deposited with a selectivity of at least about 1.3:1 on the non-metallic material relative to the metallic material.
4. The processing method of claim 1 , wherein the deposition process is a PECVD process comprising a direct plasma at a plasma power in the range of about 1 to less than about 700 mWatts/cm 2 and a substrate temperature of ≤500° C.
5. The processing method of claim 4 , wherein a plasma power is provided every about 0.00001 to about 100 seconds for a duration of about 0.0000001 to about 90 seconds.
6. The processing method of claim 4 , wherein the PECVD process comprises a direct plasma at a frequency in the range of about 10 kHz to about 50 MHz.
7. The processing method of claim 1 , wherein the titanium film is titanium nitride.
8. A method of selective deposition, the method comprising:
exposing a substrate comprising a metallic material having a first surface and a non-metallic material having a second surface to an organometallic precursor and a reactant to form a titanium film on the second surface relative to the first surface, the organometallic precursor substantially free of halogen and substantially free of oxygen and the organometallic precursor comprising a structure selected from
wherein R is hydrogen (H) or —(CH 2 ) n , R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen (H) and alkyl, R 5 , R 6 , and R 7 independently comprise an alkylamine, X and Y are independently selected from carbon (C) or nitrogen (N), and n is a number in a range of from 0 to 8.
9. The method of claim 8 , wherein the titanium film is titanium nitride.
10. A method of forming metal vias, the method comprising:
exposing a substrate to a blocking compound to selectively form a blocking layer on a metallic material surface relative to a non-metallic material surface, the substrate comprising a substrate surface with at least one feature formed therein, the at least one feature having a sidewall and a bottom, the sidewall comprising the non-metallic material surface, the bottom comprising the metallic material surface;
sequentially exposing the substrate to an organometallic precursor and a reactant to form a barrier layer on the non-metallic material surface relative to the blocking layer on the metallic material surface, the organometallic precursor substantially free of halogen and substantially free of oxygen and the organometallic precursor comprising a structure selected from
wherein R is hydrogen (H) or —(CH 2 ) n , R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen (H) and alkyl, R 5 , R 6 , and R 7 independently comprise an alkylamine, X and Y are independently selected from carbon (C) or nitrogen (N), and n is a number in a range of from 0 to 8;
optionally removing the blocking layer from the metallic material surface; and
depositing a conductive fill material within the at least one feature to form a low-resistance metal via.
11. The method of claim 10 , wherein the barrier layer comprises titanium nitride.