Cycloheptatriene molybdenum (0) precursors for deposition of molybdenum films
Molybdenum(0) coordination complexes comprising at least one cycloheptatriene ligand and optionally one or more neutral ligands which coordinate to the metal center by carbon, nitrogen or phosphorous are described. Methods for depositing molybdenum-containing films on a substrate are described. The substrate is exposed to a molybdenum precursor and a reactant to form the molybdenum-containing film (e.g., elemental molybdenum, molybdenum oxide, molybdenum carbide, molybdenum silicide, molybdenum nitride). The exposures can be sequential or simultaneous.
1. A metal coordination complex comprising molybdenum(0), at least one cycloheptatriene ligand substituted with one or more alkyl group and optionally one or more neutral ligands, each neutral ligand coordinated by carbon, nitrogen or phosphorous, wherein the metal coordination complex has less than 1% halide and carbonyl groups on an atomic basis and no neutral ligand is coordinated by phosphorus if the ligand is monodentate.
2. The metal coordination complex of claim 1 comprising one or more monodentate ligand.
3. The metal coordination complex of claim 2 , wherein the one or more monodentate ligand is selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
4. The metal coordination complex of claim 1 comprising a bidentate ligand selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
5. The metal coordination complex of claim 1 comprising a tridentate ligand selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
6. A method of depositing a film, the method comprising:
exposing a substrate to a molybdenum(0) precursor of claim 1 ; and
exposing the substrate to a reactant to react with the molybdenum(0) precursor to form a molybdenum film on the substrate.
7. The method of claim 6 , wherein the molybdenum(0) precursor comprises one or more monodentate ligand.
8. The method of claim 7 , wherein the one or more monodentate ligand is selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
9. The method of claim 6 , wherein the molybdenum(0) precursor comprises a bidentate ligand selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
10. The method of claim 6 , wherein the molybdenum(0) precursor comprises a tridentate ligand selected from one or more of:
and wherein each R may be independently selected from Me-, Et-, iPr-, and tBu-.
11. The method of claim 6 , wherein the reactant comprises one or more of one or more of an oxidizing agent and a reducing agent.
12. The method of claim 6 , wherein the molybdenum film comprises one or more of a molybdenum metal (elemental Mo) film, a molybdenum oxide film, a molybdenum carbide film, a molybdenum silicide film, and a molybdenum nitride film.
13. The method of claim 6 , wherein the substrate is exposed to the molybdenum(0) precursor and the reactant sequentially.
14. The method of claim 6 , wherein the substrate is exposed to the molybdenum(0) precursor and the reactant simultaneously.
15. The method of claim 6 , further comprising purging the substrate of the molybdenum(0) precursor prior to exposing the substrate to the reactant.
16. The method of claim 15 , further comprising purging the substrate of the reactant and repeating the method to provide a molybdenum film having a thickness in a range of from about 0.3 nm to about 100 nm.
17. A method of depositing a film, the method comprising:
forming a molybdenum-containing film in a process cycle comprising sequential exposure of a substrate to a molybdenum(0) precursor of claim 1 , purge gas, reactant, and purge gas.