Group III nitride semiconductor device and method for manufacturing the same, group III nitride semiconductor light-emitting device and method for manufacturing the same, and lamp
AssigneeToyoda Gosei Co., Ltd.
InventorsHisayuki Miki, Yasunori Yokoyama
Life of this patent
Estimating the term…
Abstract
A Group III nitride semiconductor device of the present invention is obtained by laminating at least a buffer layer (12) made of a Group III nitride compound on a substrate (11), wherein the buffer layer (12) is made of AlN, and a lattice constant of a-axis of the buffer layer (12) is smaller than a lattice constant of a-axis of AlN in a bulk state.
Claims10
A Group III nitride semiconductor device which is obtained by laminating at least a buffer layer made of a Group III nitride compound and a ground layer made of a Group III nitride semiconductor, which is formed on the buffer layer, on a substrate, wherein
- the buffer layer is formed of a single crystalline structure,
- the buffer layer is made of AlN,
- a thickness of the buffer layer is within a range of 20 to 100 nm,
- a lattice constant of a-axis of the buffer layer is smaller than a lattice constant of a-axis of AlN in a bulk state,
- the ground layer is made of GaN and is in contact with the buffer layer, and
- lattice constants of the buffer layer satisfy a relationship represented by a formula (1):
- (c0−c)/(a0−a)≧−1.4 (1)
- wherein in the formula (1), c0 represents a lattice constant of c-axis of a bulky AlN, c represents a lattice constant of c-axis of the buffer layer, a0 represents a lattice constant a-axis of bulky AlN, and a represents a lattice constant of a-axis of the buffer layer.
A method for manufacturing a Group III nitride semiconductor device, comprising:
- laminating at least a buffer layer made of a Group III nitride compound and a ground layer made of a Group III nitride semiconductor, which is formed on the buffer layer, on a substrate, wherein
- a thickness of the buffer layer is within a range of 20 to 100 nm,
- the buffer layer is formed of a single crystalline structure,
- the buffer layer is made of AlN under a condition where a lattice constant of a-axis of the buffer layer is smaller than a lattice constant of a-axis of AlN in a bulk state'
- the ground layer is made of GaN and is in contact with the buffer layer, and
- lattice constants of the buffer layer satisfy a relationship represented by a formula (1):
- (c0−c)/(a0−a)≧−1.4 (1)
- wherein in the formula (1), c0 represents a lattice constant of c-axis of a bulky AlN, c represents a lattice constant of c-axis of the buffer layer, a0 represents a lattice constant a-axis of bulky AlN, and a represents a lattice constant of a-axis of the buffer layer.
Dependencies are inferred from the claim text.