Nitride semiconductor light emitting device and manufacturing method thereof

Abstract

An object is to provide a nitride semiconductor light emitting device capable of attaining high light emission output while lowering Vf, as well as to provide a manufacturing method thereof. The invention relates to a nitride semiconductor light emitting device, including at least an n-type nitride semiconductor, a p-type nitride semiconductor and an active layer formed between said n-type nitride semiconductor and said p-type nitride semiconductor, wherein the n-type nitride semiconductor includes a multi-layered nitride semiconductor layer having at least twice repeated stacked structure consisting of a first nitride semiconductor layer and a second nitride semiconductor layer, the multi-layered nitride semiconductor layer is formed in contact with the active layer, the first nitride semiconductor layer is a layer containing an n-type impurity, and the second nitride semiconductor layer is an undoped layer or a layer containing said n-type impurity to a concentration lower than said first nitride semiconductor layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an exemplary structure of the nitride semiconductor light emitting device in accordance with the present invention.

FIGS. 2 and 3 show other exemplary structures of the nitride semiconductor light emitting device in accordance with the present invention.

FIG. 4 illustrates a common nitride semiconductor light emitting device.

FIG. 5 shows a structure of a nitride semiconductor light emitting device formed as Comparative Example 2.

FIG. 6 shows a structure of a nitride semiconductor light emitting device formed as Comparative Example 4.

Claims

1. A nitride semiconductor light emitting device, comprising: at least an n-type nitride semiconductor, a p-type nitride semiconductor and an active layer formed between said n-type nitride semiconductor and said p-type nitride semiconductor; whereinsaid n-type nitride semiconductor includes a multi-layered nitride semiconductor layer having a stacked structure consisting of a first nitride semiconductor layer and a second nitride semiconductor layer repeated at least twice;said multi-layered nitride semiconductor layer is formed in contact with said active layer; andsaid first nitride semiconductor layer is a layer containing an n-type impurity, and said second nitride semiconductor layer is an undoped layer or a layer containing said n-type impurity to a concentration lower than said first nitride semiconductor layer.

2. A method of manufacturing the nitride semiconductor light emitting device according to claim 1, comprising the steps of stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

3. The nitride semiconductor light emitting device according to claim 1, wherein said multi-layered nitride semiconductor layer consists of GaN layers.

4. A method of manufacturing the nitride semiconductor light emitting device according to claim 3, comprising the steps of: stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

5. The nitride semiconductor light emitting device according to claim 1, wherein n-type impurity concentration of said first nitride semiconductor layer is higher than 1×1018/cm3; andn-type impurity concentration of said second nitride semiconductor layer is not higher than 1×1018/cm3.

6. A method of manufacturing the nitride semiconductor light emitting device according to claim 5, comprising the steps of: stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

7. The nitride semiconductor light emitting device according to claim 5, wherein said multi-layered nitride semiconductor layer consists of GaN layers.

8. A method of manufacturing the nitride semiconductor light emitting device according to claim 7, comprising the steps of stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

9. The nitride semiconductor light emitting device according to claim 1, wherein thickness of each of said first nitride semiconductor layer and said second nitride semiconductor layer is at most 100 nm.

10. A method of manufacturing the nitride semiconductor light emitting device according to claim 9, comprising the steps of: stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

11. The nitride semiconductor light emitting device according to claim 9, wherein said multi-layered nitride semiconductor layer consists of GaN layers.

12. A method of manufacturing the nitride semiconductor light emitting device according to claim 11, comprising the steps of: stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

13. The nitride semiconductor light emitting device according to claim 9, wherein n-type impurity concentration of said first nitride semiconductor layer is higher than 1×1018/cm3; andn-type impurity concentration of said second nitride semiconductor layer is not higher than 1×1018/cm3.

14. A method of manufacturing the nitride semiconductor light emitting device according to claim 13, comprising the steps of stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.

15. The nitride semiconductor light emitting device according to claim 13, wherein said multi-layered nitride semiconductor layer consists of GaN layers.

16. A method of manufacturing the nitride semiconductor light emitting device according to claim 15, comprising the steps of: stacking said n-type nitride semiconductor including said multi-layered nitride semiconductor layer;forming said active layer; andstacking said p-type nitride semiconductor layer; whereinsaid multi-layered nitride semiconductor layer is grown by organic metal vapor deposition in a carrier gas containing nitrogen at a growth temperature of 500 to 1000° C.