Methods of ion implantation and ion sources used for the same are provided. The methods involve generating ions from a source feed gas that comprises multiple elements. For example, the source feed gas may comprise boron and at least two other elements (e.g., XaBbYc). The use of such source feed gases can lead to a number of advantages over certain conventional processes including enabling use of higher implant energies and beam currents when forming implanted regions having ultra-shallow junction depths. Also, in certain embodiments, the composition of the source feed gas may be selected to be thermally stable at relatively high temperatures (e.g., greater than 350° C.) which allows use of such gases in many conventional ion sources (e.g., indirectly heated cathode (IHC), Bernas) which generate such temperatures during use.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an ion implantation system according to an embodiment of the invention.
FIG. 2 illustrates an ion source according to an embodiment in the invention.
Claims
1. A method of implanting ions comprising:
generating ions from a source feed gas comprising boron and at least two additional elements; andimplanting the ions in a material.
2. The method of claim 1, wherein the source feed gas comprises at least boron and carbon.
3. The method of claim 2, wherein the source feed gas further comprises at least hydrogen.
4. The method of claim 1, wherein the source feed gas comprises at least boron and hydrogen.
5. The method of claim 1, wherein the source feed gas further comprises at least a third additional element.
6. The method of claim 1, wherein the source feed gas comprises XBY, wherein X and Y each represent at least one element.
7. The method of claim 6, wherein X and/or Y are organic species.
8. The method of claim 6, wherein X and/or Y are inorganic species.
9. The method of claim 6, wherein the source feed gas comprises XBbHc.
10. The method of claim 6, wherein the source feed gas comprises CaBbHc.
11. The method of claim 10, wherein the source feed gas comprises C2B10H12.
12. The method of claim 1, wherein the source feed gas comprises a compound selected from the group consisting of NaBbHc, PaBbHc, AsaBbHc and SbaBbHc.
13. The method of claim 1, wherein the source feed gas comprises a compound selected from the group consisting of SiaBbHc, GeaBbHc and SnaBbHc.
14. The method of claim 1, wherein the source feed gas comprises (NH4)aBbHc or (NH3)aBbHc.
15. The method of claim 1, further comprising producing the source feed gas by sublimation or evaporation of a source feed material.
16. The method of claim 15, wherein the source feed material is in powder form.
17. The method of claim 1, wherein the source feed gas comprising boron and at least two elements is a single gaseous composition.
18. The method of claim 1, wherein the source feed gas comprising boron and at least two elements is a mixture of more than one gas.
19. The method of claim 1, wherein the source feed gas comprises XaBbYc and b is greater than 2.
20. The method of claim 1, wherein the source feed gas comprises XaBbYc and b is greater than 8.
22. The method of claim 1, wherein the source feed gas comprises XaBbYc and c is greater than 8.
23. The method of claim 1, wherein the source feed gas has a decomposition temperature of at least 350° C.
24. The method of claim 1, further comprising accelerating the ions to an equivalent boron energy of less than 5 keV prior to implanting the ions.
25. The method of claim 1, wherein the material is a semiconductor material.
26. The method of claim 1, comprising implanting the ions in a material to form a conductive region.
27. The method of claim 1, wherein the molecular weight of the source feed gas is greater than 50 amu.
28. An ion source comprising:
a chamber housing defining a chamber; anda source feed gas supply configured to introduce a source feed gas comprising boron and at least two additional elements into the chamber,wherein the ion source is configured to ionize the source feed gas within the chamber.
29. The ion source of claim 28, wherein the source feed gas comprises at least boron and carbon.
30. The ion source of claim 29, wherein the source feed gas further comprises at least hydrogen.
31. The ion source of claim 28, wherein the source feed gas comprises at least boron and hydrogen.
32. The ion source of claim 28, wherein the source feed gas comprises XBY, wherein X and Y represent at least one element.
33. The ion source of claim 28, wherein the source feed gas comprises C2B10H12.
34. The ion source of claim 28, wherein the source feed supply is configured to form the source feed gas from a solid comprising boron and at least two additional elements.
35. The ion source of claim 28, wherein the ion source is designed to ionize the source feed gas by generating a plasma in the chamber by thermionic electron emission.
36. The ion source of claim 28, wherein the ion source is designed to ionize the source feed gas in the chamber using RF or microwave energy.
37. The ion source of claim 28, wherein the ion source is designed to ionize the source feed gas in the chamber using one or more electron beams.
38. The ion source of claim 28, wherein the source feed gas comprising boron and at least two elements is a single gaseous composition.
39. The ion source of claim 28, wherein the source feed gas comprising boron and at least two elements is a mixture of more than one gas.
40. An ion implantation system comprising the ion source of claim 28.
41. A method of implanting ions comprising:
forming a source feed gas from a source feed material comprising boron and at least two additional elements;generating ions from the source feed gas; andimplanting the ions in a material.
42. The method of claim 41, wherein the source feed gas comprises boron and a single element.
43. The method of claim 41, wherein the source feed gas comprises boron and at least two additional elements.
44. The method of claim 41, wherein the molecular weight of the source feed gas is greater than 50 amu.
45. An ion source comprising:
a chamber housing defining a chamber; anda source feed gas supply configured to form a source feed gas from a source feed material comprising boron and at least two additional elements and introduce the source feed gas into the chamber,wherein the ion source is configured to ionize the source feed gas within the chamber.
46. The ion source of claim 45, wherein the source feed gas comprises boron and a single element.
47. The ion source of claim 45, wherein the source feed gas comprises boron and at least two additional elements.
48. The ion source of claim 45, wherein the molecular weight of the source feed gas is greater than 50 amu.
49. An ion implantation system comprising the ion source of claim 45.
Patent Application
20070178678
