Patent Number: 
Section: claims

1. A method of fabricating a doped III-nitride semiconductor body, comprising:placing a substrate in a reactor chamber;pumping reactant gas for growing said III-nitride semiconductor body into said reactor chamber; andimplanting ions from an implanter, disposed in an implanter chamber in communication with said reactor chamber, into said III-nitride semiconductor body to dope said III-nitride semiconductor body as said III-nitride semiconductor body is continually grown, said implanter chamber separate from said reactor chamber, and said implanter chamber comprising a plurality of subchambers;wherein said ions pass through a space under a near vacuum prior to reaching said substrate. 2. The method of claim 1, wherein said near vacuum is obtained through differential pumping of said space. 3. The method of claim 1, wherein said space is said implanter chamber that further includes an ion path extending from said implanter to said reactor chamber, said ion path being in communication with said reactor chamber. 4. The method of claim 1, further comprising measuring a dosage of said ions while implanting takes place. 5. The method of claim 4, wherein said dosage is measured using a Faraday cup. 6. The method of claim 1, further comprising changing a direction of travel of said ions. 7. The method of claim 6, wherein deflection plates are used to change direction of travel of said ions. 8. The method of claim 1, further comprising implanting said ions through a metal mask. 9. The method of claim 1, wherein said ions are implanted through rastering. 10. An apparatus for fabrication of a doped III-nitride semiconductor body, comprising:a reactor chamber to receive a substrate and reactant gas to grow a III-nitride semiconductor body on said substrate;an implanter disposed in an implanter chamber that is in communication with said reactor chamber to implant ions into said 111-nitride semiconductor body and to dope said III-nitride semiconductor body during the growth of said III-nitride semiconductor body, said implanter chamber separate from said reactor chamber, and said implanter chamber comprising a plurality of subchambers; andat least one pump coupled to said implanter chamber configured to create a near vacuum condition in said implanter chamber. 11. The apparatus of claim 10, wherein said at least one pump performs differential pumping. 12. The apparatus of claim 10, further comprising a Faraday cup disposed within said reactor chamber. 13. The apparatus of claim 10, further comprising deflection plates to change the direction of travel of said ions.