| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface-emitting element which provides both high external quantum efficiency and high response speed. SOLUTION: A plurality of barrier layers 16-28 include a second barrier layer 20 and a third barrier layer 24, which are positioned between a plurality of active layers 18-26 and have a band structure inclined in the stacking direction. Therefore, since energy Ev at the upper edge of the valence band and energy Ec at the lower edge of the conduction band are inclined in the second barrier layer 20 and the third barrier layer 24, the injected carriers are made to move quickly along the energy inclination in the barrier layers 20 and 24, and the moving speed of the carriers left in the barrier layers 20 and 24 is increased at a light emission stop, when the application of a drive voltage is stopped. Therefore, in a light-emitting diode having a multi-quantum well structure, the fall time is shortened, and a surface-emitting element that provides both high external quantum efficiency and high response speed is obtained. |
