| 摘要 |
PROBLEM TO BE SOLVED: To reduce the threshold of a highly reliable semiconductor laser containing no much cracks and having an FFP showing a uni-modal property, and to operate the laser with a low voltage so that the laser may be used practically for optical disks, etc. SOLUTION: In a semiconductor laser which is composed of a gallium nitride compound semiconductor and has a double heterostructure in which an MQW active layer 118 is held between p- and n-type AlGaN clad layers 115 and 121, a p-type InGaN light absorbing layer 122 having higher absorptance than the p-type clad layer 121 has is arranged on the side of the clad layer 121 opposite to the active layer 118 and a p-type InAlGaN low-refractive-index layer 124 having a lower refractive index than the clad layer 121 is arranged on the outside of the light absorbing layer 122. |
