Method for producing nitride monocrystals
View Patent ↗The inventive method exploits the fact that in solutions or melts which contain certain organic substances, small nitride crystallites consisting of GaN or AlN are formed by thermal reaction and decomposition. A vessel containing the melt is kept at a first temperature T 1 . In the vessel is a substrate nucleus of be nitride to be formed, which is heated to second temperature T 2 through the input of energy, where T 2 >T 1 . Epitaxial growth from the melt then takes place on the surface of the substrate nucleus. The energy input can be carried out in different ways.
1. Method for producing a substrate of a nitride monocrystal suitable for semiconductor manufacture, characterized by the process steps
preparation of a solution or melt containing an organic compound at a first temperature T 1 , wherein
the organic compound contains the atomic constituents of the nitride monocrystal to be formed, and wherein
there is a substrate nucleus of the nitride to be grown or of a related nitride in the melt, supplying thermal energy to the substrate nucleus so that a temperature T 2 is reached at least by its surface in contact with the melt, wherein T 2 >T 1 .
2. Method pursuant to claim 1 , characterized by the fact that
the melt is in a container, and
the substrate nucleus is positioned along at least one section of the container wall, and
the thermal energy is supplied to the substrate nucleus through this section of the container wall.
3. Method pursuant to claim 2 , characterized by the fact that
the thermal energy is supplied by the radiation of a radiation source, particularly of an infrared radiation source.
4. Method pursuant to claim 2 , characterized by the fact that
the thermal energy is supplied by inductive coupling.
5. Method pursuant to claim 2 , characterized by the fact that
the thermal energy is supplied by a resistance heater, that contains resistance wires powered with an electrical current, which are in contact with the container wall.
6. Method pursuant to claim 2 , characterized by the fact that
the resistance wires are embedded in the container wall.
7. Method pursuant to claim 2 , characterized by the fact that
the thermal energy is supplied by microwave radiation.
8. Method pursuant to claim 1 , characterized by the fact that
the thermal energy is supplied by the radiation of a radiation source, particularly of an infrared radiation source.
9. Method pursuant to claim 1 , characterized by the fact that
the thermal energy is supplied by inductive coupling.
10. Method pursuant to claim 1 , characterized by the fact that
the thermal energy is supplied by a resistance heater, that contains resistance wires powered with an electrical current, which are in contact with the container wall.
11. Method pursuant to claim 10 , characterized by the fact that
the resistance wires are embedded in the container wall.
12. Method pursuant to claim 1 , characterized by the fact that
the thermal energy is supplied by microwave radiation.
13. Method pursuant to claim 1 , characterized by the fact that
the nitride is AlN, and
the organic compound is bis(dichloro-N-trimethylsilyl) cycloaminoalane.
14. Method pursuant to claim 1 , characterized by the fact that
the nitride is GaN, and
the organic compound is (trimethylsilyl)aminogallium dichloride or methyl(trimethylsilyl)aminogallium dichloride.
15. A method for producing a substrate of a nitride monocrystal suitable for semiconductor manufacture, characterized by the process steps:
preparing a solution or melt containing an organic compound at a first temperature T 1 , wherein the organic compound contains the atomic constituents of the nitride monocrystal to be formed, and wherein there is a substrate nucleus of the nitride to be grown or of a related nitride in the solution or melt; and
supplying thermal energy to the substrate nucleus so that a temperature T 2 is reached at least by its surface in contact with the melt, wherein T 2 >T 1 .
16. The method of claim 15 , wherein the solution or melt is in a container, the substrate nucleus positioned along at least one section of the container wall, and the thermal energy is supplied to the substrate nucleus through this section of the container wall.
17. The method of claim 16 , wherein the thermal energy is supplied by a resistance heater comprising resistance wires powered with an electrical current, wherein the resistance wires are in contact with the container wall.
18. The method of claim 17 , wherein the resistance wires are embedded in the container wall.
19. The method of claim 15 , wherein the thermal energy is supplied by the radiation of an infrared radiation source.
20. The method of claim 15 , wherein the thermal energy is supplied by inductive coupling.
21. The method of claim 15 , wherein the thermal energy is supplied by microwave radiation.
22. The method of claim 15 , wherein the nitride to be grown is AlN.
23. The method of claim 22 , wherein the organic compound is bis(dichloro-N-trimethylsilyl)cycloaminoalane.
24. The method of claim 15 , wherein the nitride to be grown is GaN.
25. The method of claim 24 , wherein the organic compound is (trimethylsilyl)aminogallium dichloride or methyl(trimethylsilyl)aminogallium dichloride.
26. A method for producing a substrate of a nitride monocrystal suitable for semiconductor manufacture, characterized by the process steps:
preparing a solution or melt containing an organic compound at a first temperature T 1 , wherein the organic compound contains the atomic constituents of the nitride monocrystal to be formed, and wherein there is a substrate nucleus in the solution or melt; and
supplying thermal energy to the substrate nucleus so that a temperature T 2 is reached at least by its surface in contact with the melt, wherein T 2 >T 1 .
27. The method of claim 26 , wherein the substrate nucleus comprises a material selected to realize low dislocation densities in the nitride to be grown.
28. The method of claim 27 , wherein the substrate nucleus material is the nitride to be grown or a related nitride.
29. The method of claim 28 , wherein the substrate nucleus material is the nitride to be grown.
30. The method of claim 26 , wherein the solution or melt is in a container, the substrate nucleus is positioned along at least one section of the container wall, and the thermal energy is supplied to the substrate nucleus through this section of the container wall.
31. The method of claim 30 , wherein the thermal energy is supplied by a resistance heater comprising resistance wires powered with an electrical current, wherein the resistance wires are in contact with the container wall.
32. The method of claim 31 , wherein the resistance wires are embedded in the container wall.
33. The method of claim 26 , wherein the thermal energy is supplied by the radiation of an infrared radiation source.
34. The method of claim 26 , wherein the thermal energy is supplied by inductive coupling.
35. The method of claim 26 , wherein the thermal energy is supplied by microwave radiation.
36. The method of claim 26 , wherein the nitride to be grown is AlN.
37. The method of claim 36 , wherein the organic compound is bis(dichloro-N-trimethylsilyl)cycloaminoalane.
38. The method of claim 26 , wherein the nitride is GaN.
39. The method of claim 38 , wherein the organic compound is (trimethylsilyl)aminogallium dichloride or methyl(trimethylsilyl)aminogallium dichloride.