Group III nitride semiconductor light-emitting device and production method therefor

A Group III nitride semiconductor light-emitting devices comprising:

• a substrate;
• an n-type semiconductor layer on the substrate;
• a light-emitting layer on the n-type semiconductor layer;
• and
• a p-type semiconductor layer on the light-emitting layer, wherein
• an emission wavelength is at least one wavelength selected from 380 nm to 10 nm;
• the p-type semiconductor layer has a first p-type contact layer and a second p-type contact layer;
• the first p-type contact layer is disposed between the second p-type contact layer and the light-emitting layer;
• the first p-type contact layer is a p-type AlGaN layer;
• the second p-type contact layer is a p-type AlGaN layer;
• Al composition in the first p-type contact layer is continuously and monotonously decreased with distance from the light-emitting layer;
• Al composition in the second p-type contact layer is continuously and monotonously decreased from value of Al composition at an interface between the first p-type contact layer and the second p-type contact layer with distance from the first p-type contact layer;
• and
• absolute value of Al composition decrease rate at any position in the second p-type contact layer is larger than absolute value of Al composition decrease rate at any position in the first p-type contact layer.