| 摘要 |
PROBLEM TO BE SOLVED: To reduce a threshold current in a nitride semiconductor device where an active layer having a nitride semiconductor containing In is held between p- and n-type cladding layers, and, especially, light emission is made at a wavelength of at least 440 nm. SOLUTION: The nitride semiconductor device has first and second nitride semiconductor layers 31 and 32 between the n- and p-type cladding layers 25 and 30 and the active layer 12, the first semiconductor layer 31 is made of the nitride semiconductor containing In, and the second one 32 is made of that without any In, thus achieving asymmetric waveguide structure, avoiding deterioration in crystallizability caused by providing the nitride semiconductor containing In at the side of a p-type layer 13 and loss of light due to In by using the second semiconductor layer 32, increasing a refractive index in the waveguide by the first nitride semiconductor layer 31, and hence reducing the density of the threshold current. |
