Fabricating method of metal silicide layer, fabricating method of semiconductor device using the same and semiconductor device fabricated using the method

1. A method of fabricating a metal silicide layer, the method comprising:

forming a metal layer on a substrate;

forming a first capping layer on the metal layer before performing a first annealing process;

forming a pre-metal silicide layer by reacting the substrate with the metal layer by performing the first annealing process on the substrate;

implanting silicon into the substrate using a gas cluster ion beam (GCIB) process;

forming a second capping layer on the pre-metal silicide layer after the first annealing process and before performing a second annealing process; and

changing the pre-metal silicide layer into a metal silicide layer by performing the second annealing process on the substrate.

2. The method as claimed in claim 1 , wherein an atomic ratio of a metal to silicon in the pre-metal silicide layer is equal to or greater than 1, and an atomic ratio of a metal to silicon in the metal silicide layer is less than 1.

3. The method as claimed in claim 1 , wherein implanting silicon in the GCIB process includes using a silicon source gas, the silicon source gas including at least one of silane (SiH 4 ), disilane (Si 2 H 6 ), dichlorosilane (DCS), trichlorosilane (TCS), and hexachlorodisilane (HCD).

4. The method as claimed in claim 3 , wherein the GCIB process includes implanting at least one of carbon (C), fluorine (F 2 ), nitrogen (N 2 ), arsenic (As), boron (B), and phosphorus (P) into the substrate.

5. The method as claimed in claim 1 , wherein the second annealing process is performed at a higher temperature than the first annealing process.

6. The method as claimed in claim 1 , wherein forming the metal layer includes using at least one of nickel (Ni), platinum (Pt), titanium (Ti), cobalt (Co), hafnium (Hf), and tungsten (W).

7. A method of fabricating a semiconductor device, the method comprising:

providing a substrate having a first region and a second region;

forming a first gate and first source/drain regions in the first region and forming a second gate and second source/drain regions in the second region;

forming first and second metal layers on the first and second source/drain regions, respectively;

forming a first capping layer on the second metal layer before performing a first annealing process;

forming first and second pre-metal silicide layers on the first and second source/drain regions, respectively, by performing the first annealing process on the substrate;

implanting silicon into the second region using a gas cluster ion beam (GCIB) process while blocking the first region;

forming a second capping layer on the second pre-metal silicide layer before performing a second annealing process; and

changing the first and second pre-metal silicide layers into the first and second metal silicide layers, respectively, by performing the second annealing process on the substrate.

8. The method as claimed in claim 7 , wherein an atomic ratio of a metal to silicon in the first metal silicide layer is greater than an atomic ratio of a metal to silicon in the second metal silicide layer.

9. The method as claimed in claim 8 , wherein the atomic ratio of the metal to silicon in the first metal silicide layer is equal to or greater than 1 and the atomic ratio of the metal to silicon in the second metal silicide layer is less than 1.

10. The method as claimed in claim 7 , wherein an atomic ratio of a metal to silicon in the second pre-metal silicide layer is equal to or greater than 1 and the atomic ratio of the metal to silicon in the second metal silicide layer is less than 1.

11. The method as claimed in claim 7 , wherein a silicon source gas is used in the GCIB process, the silicon source gas including at least one of silane (SiH 4 ), disilane (Si 2 H 6 ), dichlorosilane (DCS), trichlorosilane (TCS), and hexachlorodisilane (HCD).

12. The fabricating method as claimed in claim 11 , wherein the GCIB process further includes implanting at least one of carbon (C), fluorine (F 2 ), nitrogen (N 2 ), arsenic (As), boron (B), and phosphorus (P) into the substrate.

13. The method as claimed in claim 7 , wherein the second annealing process is performed at a higher temperature than the first annealing process.

14. A method of fabricating a metal silicide layer, the method comprising:

forming a metal layer on a substrate, the substrate including silicon;

reacting the metal layer with the silicon in the substrate to form a pre-metal silicide layer on the substrate;

implanting additional silicon into the substrate using a gas cluster ion beam (GCIB) process after forming the pre-metal silicide layer; and

reacting the substrate with the pre-metal silicide layer to form a metal silicide layer on the substrate after implanting the additional silicon into the substrate, wherein the method further comprises:

forming a first capping layer on the metal layer before forming the pre-metal silicide layer, and

forming a second capping layer on the pre-metal silicide layer after removing the first capping layer.

15. The method as claimed in claim 14 , wherein the metal silicide layer has a lower metal to silicon ratio than a metal to silicon ratio of the pre-metal silicide layer.

16. The method as claimed in claim 14 , wherein an atomic ratio of a metal to silicon in the pre-metal silicide layer is equal to or greater than 1 and an atomic ratio of a metal to silicon in the metal silicide layer is less than 1.

17. The method as claimed in claim 14 , further comprising:

removing the first capping layer before forming a second capping layer; and

removing the second capping layer after forming the metal silicide layer.

18. The method as claimed in claim 14 , further comprising removing unreacted portions of the metal layer prior to implanting additional silicon into the substrate.