Hybrid silicon wafer and method of producing the same
Provided is a hybrid silicon wafer made of a wafer comprised primarily of two or more types of concentric single-crystal silicon or polycrystalline silicon prepared by mutually integrating one in a molten state and another in a solid state, and having specific resistances that differ by two orders of magnitude or more. Additionally provided is a method of manufacturing a hybrid silicon wafer, wherein high specific resistance silicon or an ingot comprised primarily of silicon is disposed at a central portion or a decentered position in a crucible, a nugget or powdered silicon having a specific resistance that is lower by two orders of magnitude or more than the ingot is filled in a void part around the ingot in the crucible, the nugget or powdered silicon is selectively melted and integrated with the ingot to form a complex, and a wafer shape is cut out therefrom. The provided hybrid silicon wafer comprises the functions of both a polycrystalline silicon wafer and a single-crystal wafer, or two or more polycrystalline silicon wafers having different functions.
1. A hybrid silicon wafer made of a wafer comprised primarily of two or more types of single-crystal silicon or polycrystalline silicon prepared by mutually integrating one in a molten state and another in a solid state and having specific resistances that differ by two orders of magnitude or more, the two or more types of single-crystal silicon or polycrystalline silicon of the wafer extending coplanar relative to each other such that an outer one of the two or more types extends laterally from and surrounds an inner one of the two or more types and forms an outer peripheral portion of the wafer.
2. The hybrid silicon wafer according to claim 1 , wherein the two or more types of single-crystal silicon or polycrystalline silicon includes single-crystal silicon disposed in, integrated with and surrounded laterally by polycrystalline silicon.
3. The hybrid silicon wafer according to claim 2 , wherein a central portion of the wafer is of high specific resistance single-crystal crystal silicon, and a portion of the wafer other than the single crystal silicon is low specific resistance polycrystalline silicon.
4. The hybrid silicon wafer according to claim 3 , wherein the low specific resistance polycrystalline silicon has a resistance of 1×10 −6 to 0.1 Ω·cm, and the high specific resistance single-crystal silicon has a resistance of 0.1 to 1×10 5 Ω·cm.
5. The hybrid silicon wafer according to claim 4 , wherein the wafer is disk-shaped, and the overall diameter of the wafer is 400 mm or more.
6. The hybrid silicon wafer according to claim 1 , wherein a central portion of the wafer is high specific resistance single-crystal silicon, and a portion of the wafer other than the single crystal silicon is low specific resistance polycrystalline silicon.
7. The hybrid silicon wafer according to claim 6 , wherein the low specific resistance polycrystalline silicon has a resistance of 1×10 −6 to 0.1 Ω·cm, and the high specific resistance single-crystal silicon has a resistance of 0.1 to 1×10 5 Ω·cm.
8. The hybrid silicon wafer according to claim 1 , wherein the wafer is disk-shaped, and the overall diameter of the wafer is 400 mm or more.
9. A method of manufacturing a hybrid silicon wafer, wherein high specific resistance silicon or an ingot comprised primarily of silicon is disposed at a central portion in a crucible, a nugget or powdered silicon having a specific resistance that is lower by two orders of magnitude or more than the ingot is filled in a void part around the ingot in the crucible, the nugget or powdered silicon is selectively melted and integrated with the ingot to form a complex, and a wafer shape is cut out therefrom to form a wafer comprised primarily of two or more types of single-crystal silicon or polycrystalline silicon having specific resistances that differ by two orders of magnitude or more, the two or more types of single-crystal silicon or of polycrystalline silicon of the wafer extending coplanar relative to each other such that an outer one of the two or more types extends laterally from and surrounds an inner one of the two or more types and forms an outer peripheral portion of the wafer.
10. The method of manufacturing a hybrid silicon wafer according to claim 9 , wherein the nugget or powdered silicon having a specific resistance that is lower by two orders of magnitude or more than the high specific resistance silicon or ingot comprised primarily of silicon is selectively melted based on induction heating.
11. The method of manufacturing a hybrid silicon wafer according to claim 10 , wherein the diameter of the complex is 400 mm or more.
12. The method of manufacturing a hybrid silicon wafer according to claim 9 , wherein the diameter of the complex is 400 mm or more.