Nitride semiconductor device and method of manufacturing nitride semiconductor device
AssigneeKabushiki Kaisha Toyota Chuo Kenkyusho
InventorsKazuyoshi Tomita, Tetsuo Narita
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Abstract
A nitride semiconductor device may comprise a p-type layer. The nitride semiconductor device may comprise a first n-type voltage-blocking layer in contact with the p-type layer. The nitride semiconductor device may comprise a second n-type voltage-blocking layer in contact with the first n-type voltage-blocking layer and separated from the p-type layer by the first n-type voltage-blocking layer. A donor concentration in the first n-type voltage-blocking layer may be lower than a donor concentration in the second n-type voltage-blocking layer. A carbon concentration in the first n-type voltage-blocking layer may be lower than a carbon concentration in the second n-type voltage-blocking layer.
Claims9
A nitride semiconductor device comprising:
- a p-type layer;
- a first n-type voltage-blocking layer in contact with the p-type layer;
- and
- a second n-type voltage-blocking layer in contact with the first n-type voltage-blocking layer and separated from the p-type layer by the first n-type voltage-blocking layer,
- wherein a donor concentration in the first n-type voltage-blocking layer is lower than a donor concentration in the second n-type voltage-blocking layer, and
- a carbon concentration in the first n-type voltage-blocking layer is lower than a carbon concentration in the second n-type voltage-blocking layer.
A method of manufacturing a nitride semiconductor device provided with a p-type layer, a first n-type voltage-blocking layer, and a second n-type voltage-blocking layer, the method comprising:
- forming the second n-type voltage-blocking layer on a nitride semiconductor substrate by an epitaxial growth method;
- forming the first n-type voltage-blocking layer in contact with the second n-type voltage-blocking layer by the epitaxial growth method;
- and
- forming the p-type layer in contact with the first n-type voltage-blocking layer and separated from the second n-type voltage-blocking layer by the first n-type voltage-blocking layer, wherein
- a growth rate of the second n-type voltage-blocking layer is higher than a growth rate of the first n-type voltage-blocking layer.
Dependencies are inferred from the claim text.