Process for producing group III nitride compound semiconductor light emitting device, group III nitride compound semiconductor light emitting device and lamp
A process for producing a group III nitride compound semiconductor light emitting device, the group III nitride compound semiconductor light emitting device and a lamp, having excellent producability and excellent light emitting characteristics are provided. Such a process for producing a group III nitride semiconductor light emitting device is a process for producing a group III nitride semiconductor light emitting device having a semiconductor layer 20 constituted by laminating an n-type semiconductor layer, a light-emitting layer 15 and a p-type semiconductor layer 16 . Each of these consists of a group III nitride semiconductor, including a step of forming at least a part of the semiconductor layer 20 by a sputtering method, in which upon forming the p-type semiconductor layer 14 by a sputtering method, a Ga target containing Ga element, and a dopant target consisting of a mixture of an element having a small crystal composition of elements contained in the p-type semiconductor layer 14 and a dopant element is used as a sputtering target, and power is applied simultaneously to both the Ga target and the dopant target.
1. A process for producing a group III nitride semiconductor light emitting device having a semiconductor layer constituted by laminating an n-type semiconductor layer, a light-emitting layer and a p-type semiconductor layer, each of which consisting of a group III nitride semiconductor, comprising a step of forming at least a part of the semiconductor layer by a sputtering method, wherein upon forming the p-type semiconductor layer by a sputtering method, a Ga target containing Ga element, and a dopant target consisting of a mixture of an element having a small crystal composition of elements contained in the p-type semiconductor layer and a dopant element is used as a sputtering target, and power is applied simultaneously to both the Ga target and the dopant target.
2. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 1 , wherein the dopant element is Mg, and the element having a small crystal composition is Al.
3. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 1 , wherein the power applied to the target upon forming the p-type semiconductor layer is applied by a high frequency method or a pulse DC method.
4. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 1 , wherein upon forming the p-type semiconductor layer, a magnetic field is rotated or swung to the sputtering target.
5. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 1 , wherein the forming of the p-type semiconductor layer is performed by a reactive sputtering method to flow a nitride raw material in a reactor.
6. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 5 , wherein the nitride raw material is nitrogen.
7. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 1 , wherein the semiconductor layer is formed on a buffer layer consisting of columnar crystal which is formed on a substrate before the semiconductor layer is formed.
8. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 7 , wherein the buffer layer consists of a group III nitride compound containing Al as a group III element.
9. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 8 , wherein the buffer layer consists of AIN.
10. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 7 , wherein the buffer layer is formed so as to cover at least 90% of the surface of the substrate.
11. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 7 , wherein the columnar crystal constituting the buffer layer has a grain ranging from 0.1 to 100 nm.
12. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 7 , wherein the buffer layer has a thickness ranging from 10 to 500 nm.
13. The process for producing a group III nitride semiconductor light emitting device as set forth in claim 7 , wherein the substrate consists of sapphire.