IP Library Granted Patent US 8,673,254
Granted Patent B2
US 8,673,254 · App. 13/040,783 · Granted Mar 18, 2014

Monocrystalline silicon carbide ingot, monocrystalline silicon carbide wafer and method of manufacturing the same

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Quick Facts
Patent No.
US 8,673,254
App. No.
13/040,783
Granted
Mar 18, 2014
Kind
B2
Abstract

Provided is a monocrystalline silicon carbide ingot containing a dopant element, wherein a maximum concentration of the dopant element is less than 5×10 17 atoms/cm 3 and the maximum concentration is 50 times or less than that of a minimum concentration of the dopant element. Also provided is a monocrystalline silicon carbide wafer made by cutting and polishing the monocrystalline silicon carbide ingot, wherein a electric resistivity at room temperature of the wafer is 5×10 3 Ωcm or more. Further provided is a method for manufacturing the monocrystalline silicon carbide including growing the monocrystalline silicon carbide on a seed crystal from a sublimation material by a sublimation method. The sublimation material includes a solid material containing a dopant element, and the specific surface of the solid material containing the dopant element is 0.5 m 2 /g or less.

Claims (9)

1. A monocrystalline silicon carbide wafer made by cutting and polishing a monocrystalline silicon carbide ingot containing a dopant element, wherein the wafer has a diameter of 50 mm or more and wherein a maximum concentration of the dopant element is less than 5×10 17 atoms/cm 3 , and not more than two times a minimum concentration of the dopant element,

wherein an electric resistivity at room temperature of the wafer is 5×10 3 Ωcm or more, and

wherein the maximum concentration of the dopant element is measured at a central portion of the wafer and the minimum concentration of the dopant element is measured at a peripheral portion about 2 mm from the edge of the wafer.

2. The monocrystalline silicon carbide wafer according to claim 1 , wherein the electric resistivity at room temperature of the wafer is 1×10 5 Ωcm or more.

3. The monocrystalline silicon carbide wafer according to claim 1 , wherein the wafer consists of a single polytype of 3C, 4H, 6H or 15R.

4. The monocrystalline silicon carbide wafer according to claim 1 , wherein the wafer consists of a single polytype of 4H.

5. The monocrystalline silicon carbide wafer according to claim 1 , wherein a diameter of the wafer is 100 mm or more.

6. A monocrystalline silicon carbide wafer made by cutting and polishing a monocrystalline silicon carbide ingot having a diameter of 50 mm or more and containing a dopant element,

wherein a concentration of the dopant element measured at a central portion of the wafer is less than 5×10 17 atoms/cm 3 , and not more than two times a concentration of the dopant element measured at a peripheral portion about 2 mm from the edge of the wafer.

Assignments (3)
CHANGE OF ADDRESS Recorded Feb 14, 2024
From: RESONAC CORPORATION
To: RESONAC CORPORATION
Reel/Frame 066599/0037 →
CHANGE OF NAME Recorded Jun 23, 2023
From: SHOWA DENKO K.K.
To: RESONAC CORPORATION
Reel/Frame 064082/0513 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 20, 2018
From: NIPPON STEEL & SUMITOMO METAL CORPORATION
To: SHOWA DENKO K.K.
Reel/Frame 045991/0704 →