摘要 |
<p>PROBLEM TO BE SOLVED: To enhance the luminous output of a light-emitting element which comprises a nitride semiconductor layer, especially a light-emitting element which emits light at a peak wavelength of 530 nm or higher. SOLUTION: In order to achieve these aims, the light-emitting element is constituted of an n-type semiconductor layer, an active layer and a p-type semiconductor layer. In the active layer, a lower-part barrier layer, a well layer, a first upper-part barrier layer and a second upper-part barrier layer are laminated sequentially, and the lower-part barrier layer. The first upper-part barrier layer and the second upper-part barrier layer are constituted of a nitride semiconductors whose compositions are different from each other. In the light- emitting element, the first upper-part barrier layer is constituted of InzAl1-zN (where 0<=z<=1), mismatching of a lattice constant is relaxed with reference to the well layer and the second upper-part barrier layer, and the sufficient difference of band gap energy can be obtained with reference to the well layer.</p> |