Electro-absorption optical modulator and manufacturing method thereof
A electro-absorption optical modulator includes a multiple quantum well composed of a plurality of layers including a plurality of quantum well layers and a plurality of barrier layers that are alternately stacked, the plurality of quantum well layers and the plurality of barrier layers including an acceptor and a donor; a p-type semiconductor layer in contact with an uppermost layer of the plurality of layers; and an n-type semiconductor layer in contact with a lowermost layer of the plurality of layers, the multiple quantum well being 10% or more and 150% or less of the p-type semiconductor layer in a p-type carrier concentration, and in the multiple quantum well, an effective carrier concentration which corresponds to a difference between the p-type carrier concentration and an n-type carrier concentration is ±10% or less of the p-type carrier concentration of the multiple quantum well.
1. An electro-ab sorption optical modulator comprising:
a multiple quantum well;
a p-type semiconductor layer in contact with a first portion of the multiple quantum well; and
an n-type semiconductor layer in contact with a second portion of the multiple quantum well,
the multiple quantum well being 10% or more and 150% or less of the p-type semiconductor layer in a p-type carrier concentration, and
in the multiple quantum well, an effective carrier concentration which corresponds to a difference between the p-type carrier concentration and an n-type carrier concentration is ±10% or less of the p-type carrier concentration of the multiple quantum well.
2. The electro-absorption optical modulator of claim 1 , wherein the p-type semiconductor layer and the n-type semiconductor layer are configured to form a separate confinement heterostructure.
3. The electro-absorption optical modulator of claim 1 , wherein each of an uppermost layer of the multiple quantum well and a lowermost layer of the multiple quantum well corresponds to one of a plurality of barrier layers of the multiple quantum well.
4. The electro-absorption optical modulator of claim 1 , wherein each of the p-type carrier concentration and the n-type carrier concentration is 1×10 17 cm −3 or more.
5. The electro-absorption optical modulator of claim 1 , wherein, in the multiple quantum well, the p-type carrier concentration is higher than the n-type carrier concentration.
6. The electro-absorption optical modulator of claim 1 , wherein, in the multiple quantum well, the p-type carrier concentration is lower than the n-type carrier concentration.
7. The electro-absorption optical modulator of claim 1 , wherein an acceptor of the multiple quantum well is at least one of Zn or Mg.
8. The electro-absorption optical modulator of claim 1 , wherein a donor of the multiple quantum well is Si.
9. The electro-absorption optical modulator of claim 1 , wherein an acceptor of the p-type semiconductor layer is the same material as an acceptor of the multiple quantum well.
10. The electro-absorption optical modulator of claim 1 , wherein a donor of the n-type semiconductor layer is the same material as a donor of the multiple quantum well.
11. The electro-absorption optical modulator of claim 1 , wherein the multiple quantum well is lower than the p-type semiconductor layer in the p-type carrier concentration.
12. The electro-absorption optical modulator of claim 1 , wherein the multiple quantum well is lower than the n-type semiconductor layer in the n-type carrier concentration.
13. The electro-absorption optical modulator of claim 1 , wherein the p-type carrier concentration and the n-type carrier concentration are higher as a layer, of a plurality of layers of the multiple quantum well, is closer to the p-type semiconductor layer.
14. A method for manufacturing an electro-ab sorption optical modulator comprising:
forming an n-type semiconductor layer;
forming a multiple quantum well, and
first portion of the multiple quantum well is placed in contact with the n-type semiconductor layer; and
forming a p-type semiconductor layer in contact with a second portion of the multiple quantum well,
the multiple quantum well being 10% or more and 150% or less of the p-type semiconductor layer in a p-type carrier concentration, and
in the multiple quantum well, an effective carrier concentration which corresponds to a difference between the p-type carrier concentration and an n-type carrier concentration is ±10% or less of the p-type carrier concentration of the multiple quantum well.
15. The method for manufacturing of claim 14 , wherein the multiple quantum well is formed by metal organic chemical vapor deposition.
16. The method for manufacturing of claim 14 , wherein the p-type semiconductor layer and the n-type semiconductor layer are configured to form a separate confinement heterostructure.
17. The method for manufacturing of claim 14 , wherein
an acceptor of the multiple quantum well is at least one of Zn or Mg, and
a donor of the multiple quantum well is Si.
18. The method for manufacturing of claim 14 , wherein at least one of:
an acceptor of the p-type semiconductor layer is the same material as an acceptor of the multiple quantum well, or
a donor of the n-type semiconductor layer is the same material as a donor of the multiple quantum well.
19. The method for manufacturing of claim 14 , wherein at least one of:
the multiple quantum well is lower than the p-type semiconductor layer in the p-type carrier concentration, or
the multiple quantum well is lower than the n-type semiconductor layer in the n-type carrier concentration.
20. The method for manufacturing of claim 14 , wherein the p-type carrier concentration and the n-type carrier concentration are higher as a layer, of a plurality of layers of the multiple quantum well, is closer to the p-type semiconductor layer.