Group III nitride semiconductor laser diode

A group III nitride semiconductor laser diode comprising:

• a group III nitride substrate having a semi-polar primary surface;
• a first cladding layer having a first conductivity type, the first cladding layer comprising aluminum-containing group III nitride, the first cladding layer being provided on the group III nitride substrate;
• an active layer provided on the first cladding layer;
• a second cladding layer having a second conductivity type, the second cladding layer comprising aluminum-containing group III nitride, the second cladding layer being provided on the active layer;
• an optical guiding layer provided between the first cladding layer and the active layer and/or between the second cladding layer and the active layer, the optical guiding layer comprising a first layer and a second layer, the first layer comprising Inx1Ga1-x1N (0≦x1<1), the second layer comprising Inx2Ga1-x2N (x1<x2<1), the second layer being provided between the first layer and the active layer, and the total thickness of the first layer and the second layer being greater than 0.1 μm and less than 0.5 μm;
• an electron-blocking layer, the optical guiding layer being provided between the second cladding layer and the active layer, the optical guiding layer being separated by the electron-blocking layer into two parts arranged in a thickness direction;
• and
• the wavelength of laser light being in a range of 480 nm to 550 nm;
• wherein the optical guiding layer is provided between the first cladding layer and the active layer;
• and
• wherein group III nitride semiconductor laser diode further comprises:
• a second optical guiding layer provided between the second cladding layer and the active layer, the second optical guiding layer comprising a first layer and a second layer, the first layer comprising Inx1Ga1-x1N (0≦x1<1), the second layer comprising Inx2Ga1-x2N (x1<x2<1), the second layer being provided between the first layer and the active layer, and the total thickness of the first layer and the second layer being greater than 0.1 μm and less than 0.5 μm.

A group III nitride semiconductor laser diode comprising:

• a group III nitride substrate having a semi-polar primary surface;
• a first cladding layer having a first conductivity type, the first cladding layer comprising aluminum-containing group III nitride, the first cladding layer being provided on the group III nitride substrate;
• an active layer provided on the first cladding layer;
• a second cladding layer having a second conductivity type, the second cladding layer comprising aluminum-containing group III nitride, the second cladding layer being provided on the active layer;
• an optical guiding layer provided between the first cladding layer and the active layer and/or between the second cladding layer and the active layer, the optical guiding layer comprising a first layer and a second layer, the first layer comprising Inx1Ga1-x1N (0≦x1<1), the second layer comprising Inx2Ga1-x2N (x1<x2<1), the second layer being provided between the first layer and the active layer, and the total thickness of the first layer and the second layer being greater than 0.1 μm and less than 0.5 μm;
• an electron-blocking layer, the optical guiding layer being provided between the second cladding layer and the active layer, the optical guiding layer being separated by the electron-blocking layer into two parts arranged in a thickness direction, a gap between the electron-blocking layer and the active layer being more than or equal to 50 nm;
• and
• the wavelength of laser light being in a range of 480 nm to 550 nm;
• wherein the optical guiding layer is provided between the first cladding layer and the active layer;
• and
• wherein group III nitride semiconductor laser diode further comprises:
• a second optical guiding layer provided between the second cladding layer and the active layer, the second optical guiding layer comprising a first layer and a second layer, the first layer comprising Inx1Ga1-x1N (0≦x1<1), the second layer comprising Inx2Ga1-x2N (x1<x2<1), the second layer being provided between the first layer and the active layer, and the total thickness of the first layer and the second layer being greater than 0.1 μm and less than 0.5 μm.