Epitaxial deposition of doped semiconductor materials
View Patent ↗A method for depositing a carbon doped epitaxial semiconductor layer comprises maintaining a pressure of greater than about 700 torr in a process chamber housing a patterned substrate having exposed single crystal material. The method further comprises providing a flow of a silicon source gas to the process chamber. The silicon source gas comprises dichlorosilane. The method further comprises providing a flow of a carbon precursor to the process chamber. The method further comprises selectively depositing the carbon doped epitaxial semiconductor layer on the exposed single crystal material.
1. A method for depositing a carbon doped epitaxial semiconductor layer, the method comprising:
maintaining a pressure of greater than about 700 torr in a process chamber housing a patterned substrate having exposed single crystal material and at least a second different exposed material;
providing a flow of a silicon source gas to the process chamber, wherein the silicon source gas comprises dichlorosilane;
providing a flow of a carbon precursor to the process chamber;
selectively depositing the carbon doped epitaxial semiconductor layer on the exposed single crystal material relative to the second exposed material at the pressure of greater than about 700 torr, thereby depositing the carbon doped epitaxial semiconductor layer on the exposed single crystal material at a rate greater than about 5 nm min −1 .
2. The method of claim 1 , further comprising providing a flow of an n-dopant hydride to the process chamber.
3. The method of claim 1 , further comprising providing a flow of hydrochloric acid (HCl) to the process chamber.
4. The method of claim 1 , further comprising providing a flow of hydrochloric acid (HCl) to the process chamber at a flow rate that is between about 10 sccm and about 160 sccm.
5. The method of claim 1 :
further comprising providing a flow of hydrochloric acid (HCl) to the process chamber at a flow rate that is between about 80 sccm and about 160 sccm; and
wherein the silicon source gas further comprises silane.
6. The method of claim 1 :
further comprising providing a flow of hydrochloric acid (HCl) to the process chamber at a flow rate that is between about 10 sccm and about 40 sccm; and
wherein the silicon source gas mixture consists essentially of dichlorosilane.
7. The method of claim 1 , further comprising providing a carrier to the process chamber, wherein the carrier is selected from the group consisting of hydrogen and helium.
8. The method of claim 1 , further comprising providing a carrier to the process chamber at a flow rate that is between about 1 slm and about 10 slm.
9. The method of claim 1 , wherein the silicon source gas further comprises silane.
10. The method of claim 1 , wherein the silicon source gas consists essentially of dichlorosilane.
11. The method of claim 1 , wherein the silicon source gas further comprises at least one of silane (SiH 4 ), trisilane (Si 3 H 8 ), and partially or fully chlorinated disilanes (Si 2 H n Cl 6-n (wherein 1≦n≦6)).
12. The method of claim 1 , wherein the silicon source gas has a partial pressure in the process chamber is between about 25 torr and about 35 torr.
13. The method of claim 1 , wherein the silicon source gas is provided to the process chamber at a flow rate that is between about 200 sccm and about 500 sccm.
14. The method of claim 1 , wherein the carbon precursor is provided to the process chamber at a flow rate that is between about 50 sccm and about 70 sccm.
15. The method of claim 1 , wherein the carbon precursor is selected from the group consisting of tetrasilylmethane (C(SiH 3 ) 4 ), methyl silane (CH 3 SiH 3 ) and 1,3-disilabutane.
16. The method of claim 1 , wherein the carbon precursor comprises (SiH z Cl 3-z ) x CH 4-x-y Cl y , wherein 1≦x≦4, and 0≦y≦3, and (x+y)≦4, and 0≦z≦3 for each of the SiH 3 Cl 3-z groups.
17. The method of claim 1 , further comprising providing a flow of an n-dopant hydride to the process chamber at a flow rate that is between about 100 sccm and about 500 sccm.
18. The method of claim 1 , further comprising providing a flow of phosphine (PH 3 ) to the process chamber.
19. The method of claim 1 , wherein the pressure maintained in the process chamber is atmospheric.
20. The method of claim 1 , wherein the carbon doped epitaxial semiconductor layer comprises between about 0.8% and about 1.2% substitutionally doped carbon in single crystal silicon.
21. The method of claim 1 , wherein carbon doped epitaxial semiconductor layer has a resistivity of less than about 0.7 Ω·cm.
22. The method of claim 1 , wherein carbon doped epitaxial semiconductor layer has a resistivity of less than about 0.5 mΩ·cm.
23. The method of claim 1 , wherein the patterned substrate is held at a temperature between about 630° C. and about 650° C. during deposition of the carbon doped epitaxial semiconductor layer.
24. The method of claim 1 , wherein the patterned substrate is held at a temperature between about 600° C. and about 660° C. during deposition of the carbon doped epitaxial semiconductor layer.
25. The method of claim 1 , wherein the patterned substrate is held at a temperature between about 600° C. and about 675° C. during deposition of the carbon doped epitaxial semiconductor layer.
26. The method of claim 1 , wherein the process chamber is a single wafer process chamber.
27. A method for depositing a carbon doped epitaxial semiconductor layer, the method comprising:
maintaining a pressure of greater than about 700 torr in a process chamber housing a patterned substrate having exposed single crystal material and at least a second different exposed material;
providing a flow of a silicon source gas to the process chamber, wherein the silicon source gas comprises dichlorosilane; and
providing a flow of a carbon precursor to the process chamber;
wherein the carbon doped epitaxial semiconductor layer is selectively deposited on the exposed single crystal material relative to the second exposed material at the pressure of greater than about 700 torr, thereby depositing the carbon doped epitaxial semiconductor layer on the exposed single crystal material at a rate greater than about 5 nm min −1 , and wherein the carbon doped epitaxial semiconductor layer thus deposited comprises between about 0.8% and about 1.2% substitutionally doped carbon in single crystal silicon.
28. The method of claim 27 , further comprising providing a flow of an n-dopant hydride to the process chamber.
29. The method of claim 27 , further comprising providing a flow of hydrochloric acid (HCl) to the process chamber.
30. The method of claim 27 , wherein the silicon source gas further comprises silane.
31. The method of claim 27 , wherein the silicon source gas consists essentially of dichlorosilane.
32. The method of claim 27 , wherein the silicon source gas further comprises at least one of silane (SiH 4 ), trisilane (Si 3 H 8 ), and dichlorosilane (Si 2 H n Cl 6-n (wherein 1≦n≦6)).
33. The method of claim 27 , wherein the carbon precursor is selected from the group consisting of tetrasilylmethane (C(SiH 3 ) 4 ), methyl silane (CH 3 SIH3), and 1,3-disilabutane.
34. The method of claim 27 , wherein the carbon precursor comprises (SiH z Cl 3-z ) x CH 4-x-y Cl y , wherein 1≦x≦4, and 0≦y<3, and (x+y)≦4, and 0≦z≦3 for each of the SiH 3 Cl 3-z groups.
35. The method of claim 27 , further comprising providing a flow of an n-dopant hydride to the process chamber at a flow rate that is between about 100 sccm and about 500 sccm.
36. The method of claim 27 , further comprising providing a flow of phosphine (PH 3 ) to the process chamber.
37. The method of claim 27 , wherein the pressure maintained in the process chamber is atmospheric.
38. The method of claim 27 , wherein carbon doped epitaxial semiconductor layer has a resistivity of less than about 0.7 mΩ·cm.
39. The method of claim 27 , wherein the patterned substrate is held at a temperature between about 630° C. and about 650° C. during deposition of the carbon doped epitaxial semiconductor layer.