Group-III nitride semiconductor laser device, and method of fabricating group-III nitride semiconductor laser device

A III-nitride semiconductor laser device comprising:

• a laser structure including a support base and a semiconductor region, the support base being comprised of a hexagonal III-nitride semiconductor and having a semipolar primary surface, and the semiconductor region being provided on the semipolar primary surface of the support base;
• and
• an electrode provided on the semiconductor region of the laser structure,
• the semiconductor region comprising a first cladding layer comprised of a first conductivity type GaN-based semiconductor, a second cladding layer being comprised of a second conductivity type GaN-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer,
• the first cladding layer, the second cladding layer, and the active layer being arranged along an axis normal to the semipolar primary surface,
• the active layer comprising a GaN-based semiconductor layer,
• a c-axis of the hexagonal III-nitride semiconductor of the support base being inclined at an angle CALPHA with respect to the normal axis toward an m-axis of the hexagonal III-nitride semiconductor,
• the laser structure comprising first and second fractured faces, the first and second fractured faces intersecting with an m-n plane defined by the normal axis and the m-axis of the hexagonal III-nitride semiconductor,
• a laser cavity of the III-nitride semiconductor laser device comprising the first and second fractured faces,
• the laser structure comprising first and second surfaces, and the first surface being opposite to the second surface,
• each of the first and second fractured faces extending from an edge of the first surface to an edge of the second surface, and
• the angle being in one of a range of not less than 45 degrees and not more than 80 degrees and a range of not less than 100 degrees and not more than 135 degrees,
• the laser structure comprising a laser waveguide on the semipolar primary surface of the support base, the laser waveguide extending in a direction of a waveguide vector, and the waveguide vector extending in a direction from one of the first and second fractured faces to another of the first and second fractured faces,
• the first fractured face making an angle β with a reference plane perpendicular to the waveguide vector in a first plane, the first plane being perpendicular to the m-n plane, and the angle β being defined on an end face of the support base in the first fractured face,
• the first fractured face making an angle α with a reference plane perpendicular to the waveguide vector in a second plane, the second plane being perpendicular to the m-n plane, and the angle α being defined on an end face of the active layer in the first fractured face,
• the angle α being different from the angle β, a sign of the angle α being the same as that of the angle β, and a difference between the angle α and the angle β being not less than 0.1 degrees.