Method and apparatus for growing a III-nitride layer
A method that includes implantation of dopants while a III-nitride body is being grown on a substrate, and an apparatus for the practice of the method.
1. An apparatus for fabrication of a doped III-nitride semiconductor body, said apparatus comprising:
a reactor chamber to receive a substrate and reactant gas to grow a III-nitride semiconductor body on said substrate;
an implanter in an implanter chamber to implant ions into said III-nitride semiconductor body and to dope said III-nitride semiconductor body during the growth of said III-nitride semiconductor body such that said doped III-nitride semiconductor body is fabricated having at least one of N type conductivity and P type conductivity, said implanter chamber being separate from said reactor chamber;
at least one pump coupled to said implanter chamber configured to create a near vacuum condition in said implanter chamber.
2. The apparatus of claim 1 , wherein said implanter chamber comprises a plurality of subchambers.
3. The apparatus of claim 1 , wherein said at least one pump performs differential pumping.
4. The apparatus of claim 1 , further comprising a Faraday cup disposed within said reactor chamber.
5. The apparatus of claim 1 , further comprising deflection plates to change a direction of travel of said ions.
6. A method of fabricating a doped III-nitride semiconductor body, said method comprising:
placing a substrate in a reactor chamber;
pumping reactant gas into said reactor chamber for growing said III-nitride semiconductor body on said substrate;
implanting ions from an implanter, disposed in an implanter chamber, into said III-nitride semiconductor body to dope said III-nitride semiconductor body during said growing said III-nitride semiconductor body such that said doped III-nitride semiconductor body is fabricated having at least one of N type conductivity and P type conductivity, said implanter chamber being separate from said reactor chamber;
wherein said ions pass through said implanter chamber subject to a near vacuum condition prior to reaching said III-nitride semiconductor body.
7. The method of claim 6 , wherein said implanter chamber comprises a plurality of subchambers.
8. The method of claim 6 , wherein said near vacuum is obtained through differential pumping.
9. The method of claim 6 , wherein said implanter chamber further includes an ion path extending from said implanter to said reactor chamber, said ion path being in communication with said reactor chamber.
10. The method of claim 6 , further comprising measuring a dosage of said ions during said implanting.
11. The method of claim 10 , wherein said dosage is measured using a Faraday cup.
12. The method of claim 6 , further comprising changing a direction of travel of said ions.
13. The method of claim 12 , wherein said direction of travel is changed by deflection plates.
14. The method of claim 6 , further comprising implanting said ions through a metal mask.
15. The method of claim 6 , further comprising implanting said ions by rastering.