Bar-shaped semiconductor laser chip and method of fabrication thereof

A bar-shaped semiconductor laser chip comprising:

• a nitride semiconductor substrate;
• and
• a semiconductor layer formed on a main surface of the nitride semiconductor substrate and comprising a plurality of laser chip portions,
• wherein
• the plurality of laser chip portions are arrayed in a [11-20] direction,
• the main surface of the nitride semiconductor substrate is a (0001) plane having an off-angle in a direction along the [11-20] direction, and
• a central part of the main surface of the nitride semiconductor substrate has an off-angle of 0.05±0.1 degrees from the (0001) plane in the direction along the [11-20] direction
• wherein
• when the off-angle of the main surface of the nitride semiconductor substrate decreases in the [11-20] direction, the central part of the main surface of the nitride semiconductor substrate has an off-angle of 0.05±0.1 degrees as measured, while facing in the [11-20] direction, from the (0001) plane to the [0001]-direction side, and
• when the off-angle of the main surface of the nitride semiconductor substrate increases in the [11-20] direction, the central part of the main surface of the nitride semiconductor substrate has an off-angle of 0.05±0.1 degrees as measured, while facing in the [-1-120] direction, from the (0001) plane to the [0001]-direction side.