1.  Field of the Invention
The present invention relates to a nitride semiconductor light-emitting diode. 
2.  Description of the Related Art
Japanese Patent Application laid-open Publication No.  2012-023249A discloses a nitride semiconductor light-emitting diode.  FIG.  13 shows a nitride semiconductor light-emitting diode disclosed in FIG.  3G included in Japanese Patent Application laid-open Publication No.  2012-023249A. Japanese Patent Application laid-open Publication No.  2012-023249A discloses in the paragraph [0199] that a nitride semiconductor light-emitting diode having a shape of a scalene triangle in a top view has higher light extraction efficiency than a nitride semiconductor light-emitting diode having a shape of a regular triangle. 
More specifically, Japanese Patent Application laid-open Publication No.  2012-023249A discloses in the paragraph [0200] that the light extraction efficiency of the scalene triangle nitride semiconductor light-emitting diode shown in FIG.  13 is 1.4 times as high as that of a regular triangle nitride semiconductor light-emitting diode. 
Furthermore, Japanese Patent Application laid-open Publication No.  2012-023249A discloses in the paragraph [0466] that it is most desirable that a nitride substrate included in the nitride semiconductor light-emitting diode has a (1-100) plane.