Optical semiconductor device
Provided is an optical semiconductor device including a laminate structural body 20 in which an n-type compound semiconductor layer 21 , an active layer 23 , and a p-type compound semiconductor layer 22 are laminated in this order. The active layer 23 includes a multiquantum well structure including a tunnel barrier layer 33 , and a compositional variation of a well layer 31 2 adjacent to the p-type compound semiconductor layer 22 is greater than a compositional variation of another well layer 31 1 . Band gap energy of the well layer 31 2 adjacent to the p-type compound semiconductor layer 22 is smaller than band gap energy of the other well layer 31 1 . A thickness of the well layer 31 2 adjacent to the p-type compound semiconductor layer 22 is greater than a thickness of the other well layer 31 1 .
1. An optical semiconductor device, comprising:
a laminate structural body that comprises:
an n-type compound semiconductor layer;
an active layer;
a p-type compound semiconductor layer, wherein
an order of arrangement is the n-type compound semiconductor layer, the active layer, and the p-type compound semiconductor layer, respectively,
the active layer includes a multiquantum well structure including a first well layer, a first tunnel barrier layer, a first barrier layer, a second tunnel barrier layer, and a second well layer,
the first barrier layer is between the first tunnel barrier layer and the second tunnel barrier layer, and
a compositional variation of the first well layer is greater than a compositional variation of the second well layer;
an electron barrier layer adjacent to the active layer; and
a non-doped compound semiconductor layer between the active layer and the electron barrier layer.
2. The optical semiconductor device according to claim 1 , wherein the non-doped compound semiconductor layer is a non-doped InGaN layer.
3. The optical semiconductor device according to claim 1 , wherein the non-doped compound semiconductor layer is a non-doped AlGaN layer.
4. The optical semiconductor device according to claim 1 , wherein the electron barrier layer is a p-type AlGaN.