| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface light emitting diode having both high response speed and high light emission output. SOLUTION: This light emitting diode 20 is composed of a quantum well layer 32, which functions as a light emitting layer, and spacers 30 and 34 of 5nm or thereabout in thickness containing no In and Al which are contained in a pair of graded layers 28 and 36. Consequently, as the graded layers 28 and 36 are provided pinching the quantum well layer 32, band gap energy is incliningly formed corresponding to the inclination of composition, and the carrier injected by a signal input advances quickly to the quantum well layer 23 along the above-mentioned inclination, a high response speed can be obtained. In this case, as the spacers 30 and 34, containing no In and Al, are provided between the graded layers 28 and 36 adjacent to them, a high light-emitting output can be obtained. |
