Photonuclear transmutation doping in gallium-based semiconductor materials
View Patent ↗The present invention relates to various high quality n-type and p-type doped gallium-based semiconductor materials, electronic components incorporating these materials, and processes of producing these materials. In particular, The present invention relates processes to achieve high quality, uniform doping of a whole wafer or a thin layer of gallium-based semiconductor materials for various applications such as a vertical power transistor or diode.
1. A process for producing a doped gallium-based semiconductor material comprising:
irradiating a gallium-based semiconductor workpiece with gamma rays in a photonuclear reaction to effect transmuting at least a portion of Ga in the workpiece to Zn and/or Ge to produce the doped gallium-based semiconductor material,
wherein the gallium-based semiconductor workpiece comprises at least one other component selected from group consisting of N, O, Sb, In, and combinations thereof.
2. The process of claim 1 , wherein Ga is transmuted to Zn.
3. The process of claim 1 , wherein 69 Ga is transmuted to 68 Zn and/or 71 Ga is transmuted to 70 Zn.
4. The process of claim 1 , wherein the gamma rays have an incident photon energy that is 7.5 MeV or more.
5. The process of claim 1 , wherein the gamma rays have an incident photon energy that is 20.5 MeV or less.
6. The process of claim 2 , wherein the gamma rays have an incident photon energy that is in the range of from 7.5 MeV to 10 MeV.
7. The process of claim 1 , wherein the doped gallium-based semiconductor material is a p-type doped gallium-based semiconductor material.
8. The process of claim 1 , wherein Ga is transmuted to Ge.
9. The process of claim 8 , wherein the gamma rays have an incident photon energy that is 9.5 MeV or more.
10. The process of claim 8 , wherein the gamma rays have an incident photon energy that is in the range of from 9.5 MeV to 50 MeV.
11. The process of claim 1 , wherein the doped gallium-based semiconductor material is a n-type doped gallium-based semiconductor material.
12. The process of claim 1 , further comprising shielding a first region of the gallium-based semiconductor workpiece with a high-Z material during irradiation to selectively dope a second region of the workpiece that is unshielded.
13. The process of claim 12 , wherein the high-Z material comprises at least one component selected from the group consisting of Pb, W, Bi, Sn, Sb, Fe, Pt, Ta, a composite thereof, and metal foam thereof.
14. The process of claim 1 , wherein the gallium-based semiconductor workpiece comprises GaN.
15. The process of claim 1 , further comprising annealing the doped gallium-based semiconductor material.
16. The process of claim 1 , wherein the doped gallium-based semiconductor material is not radioactive after irradiation.
17. A process for producing a doped gallium-based semiconductor material comprising:
irradiating a gallium-based semiconductor workpiece with gamma rays in a photonuclear reaction to effect transmuting at least a portion of Ga in the workpiece to Zn and/or Ge to produce the doped gallium-based semiconductor material,
wherein the gallium-based semiconductor workpiece comprises gallium oxide.