Method of manufacturing a silicon ingot and silicon ingot
A method of Czochralski growth of a silicon ingot includes melting a mixture of silicon material and an n-type dopant material in a crucible. The silicon ingot is extracted from the molten silicon during an extraction time period. The silicon ingot is doped with additional n-type dopant material during at least one sub-period of the extraction time period.
1. A method of magnetic Czochralski (MCZ) growth of a silicon ingot, the method comprising:
melting a mixture of silicon material and an n-type dopant material in a crucible;
extracting the silicon ingot from the molten mixture during an extraction time period by the MCZ growth, thereby doping the silicon ingot with the n-type dopant material of the molten mixture; and
doping the silicon ingot with additional n-type dopant material during at least one sub-period of the extraction time period,
wherein the silicon ingot comprises a first silicon ingot part and a second silicon ingot part,
wherein doping the silicon ingot with additional n-type doping material is in addition to doping the silicon ingot with the n-type dopant material of the molten mixture, and wherein doping the silicon ingot with the additional n-type doping material starts after the first silicon ingot part has been grown and ends before the second silicon ingot part is grown.
2. The method of claim 1 , wherein the additional n-type dopant material is phosphorus.
3. The method of claim 1 , wherein the silicon ingot is doped with the additional n-type dopant material by a vapor phase doping technique.
4. The method of claim 3 , further comprising controlling inlet of a dopant precursor gas into a reaction chamber including the silicon ingot.
5. The method of claim 1 , wherein doping the silicon ingot with the additional n-type dopant material includes melting an n-type dopant source material in the crucible.
6. The method of claim 5 , wherein the silicon ingot is doped with the additional n-type dopant material by adjusting a depth of the n-type dopant source material into the molten silicon, the n-type dopant source material including the additional n-type dopant material.
7. The method of claim 6 , wherein adjusting the depth of the n-type dopant source material dipped into the molten silicon in the crucible includes measuring a weight of the n-type dopant source material.
8. The method of claim 5 , wherein the n-type dopant source material is in the shape of one or more rods.
9. The method of claim 5 , wherein the n-type dopant source material is made of quartz or silicon carbide doped with the additional n-type dopant material.
10. The method of claim 5 , wherein a concentration profile of the additional n-type dopant material into a depth of the n-type dopant source material has a peak below a surface of the n-type dopant source material.
11. The method of claim 10 , wherein introducing the n-type dopant material into the n-type dopant source material is carried out by at least one of the processes in-situ doping, plasma deposition through a surface of the n-type dopant source material, ion implantation through the surface of the n-type dopant source material and diffusion through the surface of the n-type dopant source material.
12. The method of claim 1 , further comprising altering a degree of doping the silicon ingot with the additional n-type dopant material during the extraction time period between no doping and maximum doping.
13. The method of claim 1 , further comprising setting a net n-type doping in the silicon ingot between 1×10 13 cm −3 and 1×10 15 cm −3 .
14. The method of claim 1 , further comprising partially counter-doping the silicon ingot with p-type dopant material by adding the p-type dopant material to the silicon melt via at least one of a p-type dopant source material or by a vapor phase doping technique.
15. The method of claim 14 , wherein the p-type dopant material is at least one of boron, aluminum and gallium.
16. The method of claim 14 , wherein the silicon ingot is doped with the p-type dopant material by a vapor phase doping technique.
17. The method of claim 14 , wherein doping the silicon ingot with the p-type dopant material includes melting a p-type dopant source material in the crucible.
18. The method of claim 17 , wherein the silicon ingot is doped with the p-type dopant material by adjusting a depth of the p-type dopant source material into the molten silicon, the p-type dopant source material including the additional n-type dopant material.
19. The method of claim 17 , wherein adjusting the depth of the p-type dopant source material dipped into the molten silicon in the crucible includes measuring a weight of the p-type dopant source material.
20. The method of claim 17 , wherein the p-type dopant source material is in the shape of one or more rods.
21. The method of claim 17 , wherein the p-type dopant source material is made of quartz or silicon carbide doped with the additional n-type dopant material.
22. The method of claim 17 , wherein a concentration profile of the p-type dopant material into a depth of the p-type dopant source material has a peak below a surface of the p-type dopant source material.
23. The method of claim 17 , wherein introducing the p-type dopant material into the p-type dopant source material is carried out by at least one of the processes in-situ doping, plasma deposition through a surface of the p-type dopant source material, ion implantation through the surface of the p-type dopant source material and diffusion through the surface of the p-type dopant source material.
24. The method of claim 17 , further comprising altering a degree of doping the silicon ingot with the additional n-type dopant material during the extraction time period between no doping and maximum doping.