A semiconductor laser device is constructed by stacking a buffer layer, an undoped
GaN layer, an n-GaN contact layer, an n-InGaN crack preventing layer, an n-AlGaN
cladding layer, a light emitting layer, a p-AlGaN cladding layer, and a p-GaN contact
layer in this order. A ridge portion comprising the p-GaN contact layer and the
p-AlGaN cladding layer is formed, and the thickness of the p-AlGaN cladding layer
in the ridge portion is less than 0.3 m.