Enhancing gapfill performance of dram word line

1. A method of forming a film, the method comprising:

forming a molybdenum-silicide film in a first process cycle comprising sequential exposure of a substrate to a molybdenum precursor, purge gas, a silane precursor, and purge gas, the substrate comprising a plurality of trenches with a gate oxide layer conformally deposited thereon and the molybdenum-silicide film formed in a bottom of the plurality of trenches on the gate oxide layer, the molybdenum precursor comprising one or more of molybdenum chloride (MoCl 5 ), molybdenum fluoride (MoF 6 ), molybdenum iodide (Mol 6 ), molybdenum bromide (MoBr 3 ), molybdenum hexacarbonyl (Mo(CO) 6 ), molybdenum dichloride dioxide (MoO 2 Cl 2 ), molybdenum oxytetrachloride (MoOCl 4 ), Tetrakis(dimethylamino)molybdenum(IV), and Bis(tert-butylimido)-bis(dimethylamido)molybdenum; and

forming a soaked substrate having a titanium species thereon without forming a titanium nitride film in a second process cycle, the second process cycle consisting of flowing a titanium precursor in an atmosphere of argon (Ar) gas over the substrate, and purging the soaked substrate of unreacted titanium precursor, wherein the soaked substrate is formed prior to the first process cycle or wherein the soaked substrate is formed after the first process cycle.

2. The method of claim 1 , wherein purging comprises one or more of applying a vacuum or flowing a purge gas over the substrate.

3. The method of claim 1 , further comprising exposing the substrate to a second molybdenum precursor and a reactant to fill the plurality of trenches with a bulk molybdenum film.

4. The method of claim 3 , further comprising annealing the substrate, wherein the bulk molybdenum film has line bending of less than 2 nm, there is no delamination of the bulk molybdenum film, and the bulk molybdenum film does not have voids.

5. A method of forming a film, the method comprising:

forming a titanium nitride film in a first process cycle, the first process cycle comprising exposing a substrate to a first titanium precursor and exposing the substrate to a nitrogen-containing reactant, the substrate comprising a plurality of trenches with a gate oxide layer conformally deposited thereon;

forming a soaked substrate having a titanium species thereon without forming a titanium nitride film in a second processing cycle, the second processing cycle consisting of flowing a first titanium precursor in an atmosphere of argon (Ar) gas over the substrate, and purging the soaked substrate of unreacted first titanium precursor; and

forming a molybdenum-silicide film in a third process cycle comprising sequential exposure of a substrate to a molybdenum precursor, purge gas, a silane reactant, and purge gas, the molybdenum-silicide film formed in a bottom of the plurality of trenches on the gate oxide layer, the molybdenum precursor comprising one or more of molybdenum chloride (MoCl 5 ), molybdenum fluoride (MoF 6 ), molybdenum iodide (Mol 6 ), molybdenum bromide (MoBr 3 ), molybdenum hexacarbonyl (Mo(CO) 6 ), molybdenum dichloride dioxide (MoO 2 Cl 2 ), molybdenum oxytetrachloride (MoOCl 4 ) Tetrakis(dimethylamino)molybdenum(IV), and Bis(tert-butylimido)-bis(dimethylamido)molybdenum, wherein the first process cycle is performed first, followed by the second process cycle, then the third process cycle.

6. The method of claim 5 , further comprising repeating the method to fill the plurality of trenches.

7. The method of claim 6 , further comprising annealing the substrate, wherein the molybdenum-silicide film does not have voids.

8. A method of forming a memory device, the method comprising:

conformally depositing a gate oxide layer on a substrate having a plurality of trenches therein, each trench having a surface, at least one sidewall, and a bottom, the gate oxide layer forming on the surface, along the at least one sidewall, and on the bottom of the trench;

forming a work function metal layer comprising titanium nitride on the gate oxide layer by exposing the substrate to a first titanium precursor and a nitrogen-containing reactant to form the work function metal layer;

forming a soaked substrate having a titanium species thereon without forming a titanium nitride layer in a process cycle, the process cycle consisting of flowing a second titanium precursor in an atmosphere of argon (Ar) gas over the substrate, and purging the soaked substrate of unreacted second titanium precursor, wherein the soaked substrate is formed after forming the work function metal layer;

exposing the substrate to a first molybdenum precursor and a silane reactant to form a molybdenum silicide nucleation layer on the soaked substrate;

exposing the substrate to a second molybdenum precursor and a reactant to fill the plurality of trenches with a bulk molybdenum film;

annealing the substrate, wherein the bulk molybdenum film has line bending of less than 2 nm, there is no delamination of the bulk molybdenum film, and the bulk molybdenum film does not have voids; and

recessing the annealed bulk molybdenum film to form a buried word line.

9. The method of claim 8 , wherein the substrate is exposed to the first molybdenum precursor and the silane reactant sequentially.

10. The method of claim 8 , wherein the substrate is exposed to the first molybdenum precursor and the silane reactant simultaneously.

11. The method of claim 8 , further comprising purging the surface of the substrate of the second titanium precursor prior to exposing the substrate to the first molybdenum precursor.

12. The method of claim 11 , wherein purging comprises one or more of applying a vacuum or flowing a purge gas over the substrate.

13. The method of claim 12 , wherein the purge gas comprises one or more of nitrogen (N 2 ), helium (He), and argon (Ar).