| 摘要 |
<p>A light emitting device having an electron blocking layer is disclosed. The light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, an active layer disposed between the n-type semiconductor layer and the p-type semiconductor layer, and an electron blocking layer disposed between the active layer and the p-type semiconductor layer. The electron blocking layer includes first, second, third and fourth layers, wherein the first layer is disposed closer to the active layer than the second to fourth layers and has a wider band gap than the second to fourth layers, the second layer adjoins the first layer, and the third layer is disposed between the second layer and the fourth layer and has a narrower band gap than the second and fourth layers. Thus, the light emitting device has improved hole injection efficiency and can efficiently prevent electron overflow.</p> |
