GROUP III NITRIDE SEMICONDUCTOR LASER DEVICE, METHOD FOR PRODUCING GROUP III NITRIDE SEMICONDUCTOR LASER DEVICE, METHOD FOR EVALUATING END FACET FOR OPTICAL CAVITY OF GROUP III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD FOR EVALUATING SCRIBE GROOVE

摘要

A group III nitride semiconductor laser device comprises a laser structure including a support base of the group III nitride and first and second end facets for a laser cavity, and the first and second end facets intersect with an m-n plane defined by the m-axis of the group III nitride and an axis normal to a semipolar primary surface of the support base. A +c axis vector for a c-axis of the group III nitride forms an angle ALPHA in a range of 71 to 79 degrees with the normal axis. The +c axis vector is inclined at an angle α1 of 10 to 25 degrees with one normal vector defined at one edge of the first end facet, and is inclined at an angle β1 of zero to 5 degrees with another normal vector defined at the other edge of the first end facet.

主权项

1. A group III nitride semiconductor laser device, comprising:
a laser structure including a support base and a semiconductor region, the support base being made of a hexagonal group 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, a c-axis of the group III nitride semiconductor of the support base being oriented in a direction of a <0001> axis of the group III nitride semiconductor, the direction of the <0001> axis being indicated by a +c axis vector, the semiconductor region including an active layer, and the active layer including a gallium nitride based semiconductor layer, the c-axis of the group III nitride semiconductor of the support base forming an angle ALPHA with a normal axis normal to the semipolar primary surface in a direction away from the c-axis toward a [−1010] axis of the group III nitride semiconductor, the angle ALPHA being equal to or greater than 71 degrees but equal to or less than 79 degrees, the laser structure including a first end facet and a second end facet, the first end facet and the second end facet intersecting with an m-n plane defined by the normal axis and an m-axis of the group III nitride semiconductor, and a laser cavity of the group III nitride semiconductor laser device including the first end facet and the second end facet, the laser structure including a first surface and a second surface, the first surface being provided on opposite side of the second surface, the semiconductor region being provided between the first surface and the support base, a first normal vector normal to the first end facet being defined at a first edge shared by the first end facet and the first surface, and the +c axis vector being inclined at an angle α1 with respect to the first normal vector within the m-n plane in a direction away from the [−1010] axis toward the c-axis, the angle α1 being equal to or greater than 10 degrees but equal to or less than 25 degrees, a second normal vector normal to the first end facet being defined at a second edge shared by the first end facet and the second surface, and the +c axis vector being inclined at an angle β1 with respect to the second normal vector within the m-n plane in the direction from the [−1010] axis toward the c-axis, the angle β1 being equal to or greater than zero degrees but equal to or less than 5 degrees, and an end facet of the support base and an end facet of the semiconductor region being exposed on each of the first end facet and the second end facet.