NITRIDE-BASED SEMICONDUCTOR LIGHT-EMITTING DEVICE AND METHOD FOR FABRICATING THE SAME

1 . A method for fabricating a nitride-based light-emitting device, comprising:

a step (a) of forming a nitride-based semiconductor multilayer structure including a p-type semiconductor region having an m-plane as a growing plane; and

a step (b) of forming an Ag electrode so as to be in contact with the growing plane of the p-type semiconductor region,

wherein the step (b) includes:

a step (b 1 ) of forming the Ag electrode having a thickness in a range of 200 nm or more to 1,000 nm or less; and

a step (b 2 ) of heating the Ag electrode to a temperature in a range of 400° C. or more to 600° C. or less.

2 . A method for fabricating a nitride-based semiconductor light-emitting device according to claim 1 , wherein the Ag electrode is heated under an atmosphere with an oxygen partial pressure smaller than that of air in the step (b 2 ).

3 . A method for fabricating a nitride-based semiconductor light-emitting device according to claim 2 , wherein the Ag electrode is heated to the temperature in the range of 500° C. or more to 600° C. or less in the step (b 2 ).

4 . A method for fabricating a nitride-based semiconductor light-emitting device according to claim 2 , wherein the thickness of the Ag electrode is set in a range of 200 nm or more to 500 nm or less in the step (b 1 ).

5 . A method for fabricating a nitride-based semiconductor light-emitting device according to claim 2 ,

wherein the p-type semiconductor region includes a contact layer containing Mg at a concentration in a range of 4×10 19 cm −3 or more to 2×10 20 cm −3 or less, and

wherein the contact layer is formed of an Al x Ga y In z N semiconductor having a thickness in a range of 26 nm or more to 60 nm or less, where x+y+z=1, x≧0, y>0, and z≧0.

6 . A method for fabricating a nitride-based semiconductor light-emitting device according to claim 2 , further comprising a step (c) of forming a protective film on the Ag electrode after the step (b).

7 . A nitride-based semiconductor light-emitting device fabricated by the method according to claim 2 .

8 . A nitride-based semiconductor light-emitting device, comprising:

a nitride-based semiconductor multilayer structure including a p-type semiconductor region having an m-plane as a growing plane; and

an Ag electrode provided so as to be in contact with the growing plane of the p-type semiconductor region,

wherein the Ag electrode has a thickness in a range of 200 nm or more to 1,000 nm or less, and

wherein an integral intensity ratio of X-ray intensities on a ( 111 ) plane and on a ( 200 ) plane on the growing plane of the Ag electrode is in a range of 20 or more to 100 or less.

9 . A nitride-based semiconductor light-emitting device, comprising:

a nitride-based semiconductor multilayer structure including a p-type semiconductor region having an m-plane as a growing plane; and

an Ag electrode provided so as to be in contact with the growing plane of the p-type semiconductor region,

wherein the Ag electrode has a thickness in a range of 200 nm or more to 1,000 nm or less, and

wherein a peak intensity ratio of X-ray intensities on a ( 111 ) plane and on a ( 200 ) plane on the growing plane of the Ag electrode is in a range of 30 or more to 150 or less.

10 . A nitride-based semiconductor light-emitting device according to claim 9 , wherein the Ag electrode is subjected to heat treatment under an atmosphere with an oxygen partial pressure smaller than that of air.

11 . A nitride-based semiconductor light-emitting device according to claim 10 , wherein the Ag electrode has a thickness in a range of 200 nm or more to 500 nm or less.

12 . A nitride-based semiconductor light-emitting device according to claim 10 ,

wherein the p-type semiconductor region includes a contact layer containing Mg at a concentration in a range of 4×10 19 cm −3 or more to 2×10 20 cm −3 or less, and

wherein the contact layer is formed of an Al x Ga y In z N semiconductor having a thickness in a range of 26 nm or more to 60 nm or less, where x+y+z=1, x≧0, y>0, and z≧0.

13 . A nitride-based semiconductor light-emitting device according to claim 12 , wherein the contact layer contains Mg at a concentration in a range of 4×10 19 cm −3 or more to 2×10 20 cm −3 or less and has a thickness in a range of 30 nm or more to 45 nm or less.

14 . A nitride-based semiconductor light-emitting device according to claim 10 , further comprising a protective film formed on the Ag electrode.

15 . A light source, comprising:

a nitride-based semiconductor light-emitting device; and

a wavelength conversion section containing a fluorescent substance for converting a wavelength of light emitted from the nitride-based semiconductor light-emitting device,

wherein the nitride-based semiconductor light-emitting device includes:

a nitride-based semiconductor multilayer structure including a p-type semiconductor region having an m-plane as a growing plane; and

an Ag electrode provided so as to be in contact with the growing plane of the p-type semiconductor region,

wherein the Ag electrode has a thickness in a range of 200 nm or more to 1,000 nm or less, and

wherein an integral intensity ratio of X-ray intensities on a ( 111 ) plane and on a ( 200 ) plane on the growing plane of the Ag electrode is in a range of 20 or more to 100 or less.

16 . A light source according to claim 15 , wherein the Ag electrode is subjected to heat treatment under an atmosphere with an oxygen partial pressure smaller than that of air.