Patent ID: 9379521
Filing Date: 2016-06-28
CPC Classification: G01N,H01S

Claim Text:
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.