High-power semiconductor laser device having current confinement structure and index-guides structure and oscillating in transverse mode

A semiconductor laser device comprising:

• a GaN layer of a first conductive type;
• an active layer;
• a first upper cladding layer of a second conductive type;
• a current confinement layer of said first conductive type;
• a second upper cladding layer of said second conductive type;
• and
• a GaN contact layer of said second conductive type;
• wherein said active layer, said first upper cladding layer, said current confinement layer, said second upper cladding layer, and said contact layer are formed above said GaN layer;
• a groove is formed through a full thickness of said current confinement layer so as to form an index-guided structure;
• said active layer is a single or multiple quantum well active layer formed by alternately forming at least one Inx1Ga1-x1N well and a plurality of Inx2Ga1-x2N barriers, where 0≦x2<x1<0.5;
• said current confinement layer has a superlattice structure formed with Ga1-z4Alz4N barriers and GaN wells, where 0<z4<1;
• said second upper cladding layer is formed over said current confinement layer so as to cover said groove;
• and
• said GaN contact layer is formed on an entire upper surface of said second upper cladding layer.