US Patent 7876798 Nitride semiconductor laser device

A nitride semiconductor laser device is formed by growing a group III nitride semiconductor multilayer structure on a substrate containing no Al. The group III nitride semiconductor multilayer structure forms a structure including an n-type semiconductor layer, a p-type semiconductor layer, and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer. The n-type semiconductor layer includes an n-type cladding layer containing Al and an n-type guide layer having a smaller band gap than the n-type cladding layer. The p-type semiconductor layer includes a p-type cladding layer containing Al and a p-type guide layer having a smaller band gap than the p-type cladding layer. A removal region is formed by partially removing the layers containing Al in the group III nitride semiconductor multilayer structure from the substrate.