| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical coupling layer formed from a thick n-type semiconductor layer required for both appropriate roughing and current diffusion.SOLUTION: An optical coupling layer 235 comprises one or more in-continuous layer that does not incline in terms of composition, and includes, from the n-type III-V group semiconductor layer 230 side, a first layer formed from a III-V group semiconductor material, and a second layer formed from undoped gallium nitride. The first layer and the second layer compose optical-coupling projecting shape. A metal electrode 240 is thicker than the heights of optical-coupling projecting shape, buried between the optical-coupling projections, provided in contact with the first and second layers on the optical coupling projecting shape, and electrically connected with the n-type conductive layer 230. In a direction from an active layer 225 to the n-type III-V group semiconductor layer 230, the optical-coupling projecting shape is narrowed. |
