| 摘要 |
A III nitride epitaxial substrate which makes it possible to obtain a deep ultraviolet light emitting device with improved light output power is provided. A III nitride epitaxial substrate 10 includes a substrate 12, an AIN buffer layer 14, a first superlattice laminate 16, a second superlattice laminate 18 and a III nitride laminate 20 in this order. The III nitride laminate 20 includes an active layer 24 including an Al ± Ga 1-± N (0.03 ‰¤ ± ) layer. The first superlattice laminate 16 includes Al a Ga 1-a N layers 16A and Al b Ga 1-b N (0.9 < b ‰¤ 1) layers 16B which are alternately stacked, where ± < a and a < b hold. The second superlattice laminate 18 includes repeated layer sets each having an Al x Ga 1-x N layer 18A, an Al y Ga 1-y N layer 18B, and an Al z Ga 1-z N (0.9 < z ‰¤ 1) layer 18C, where ± < x and x < y < z hold. |
