Semiconductor device including two-dimensional material, and method of manufacturing the semiconductor device
Example embodiments relate to semiconductor devices including two-dimensional (2D) materials, and methods of manufacturing the semiconductor devices. A semiconductor device may be an optoelectronic device including at least one doped 2D material. The optoelectronic device may include a first electrode, a second electrode, and a semiconductor layer between the first and second electrodes. At least one of the first electrode and the second electrode may include doped graphene. The semiconductor layer may have a built-in potential greater than or equal to about 0.1 eV, or greater than or equal to about 0.3 eV. One of the first electrode and the second electrode may include p-doped graphene, and the other may include n-doped graphene. Alternatively, one of the first electrode and the second electrode may include p-doped or n-doped graphene, and the other may include a metallic material.
1. An optoelectronic device comprising:
a first electrode;
a second electrode; and
a semiconductor active layer between the first and second electrodes, the semiconductor active layer being a photodetecting layer,
wherein the semiconductor active layer has a built-in potential of substantially 0.1 eV or greater,
wherein one of the first electrode and the second electrode includes graphene doped with a p-type dopant, and
wherein another of the first electrode and the second electrode includes graphene doped with an n-type dopant.
2. The optoelectronic device of claim 1 , wherein a built-in electric field of the semiconductor active layer is substantially 0.3 MV/cm to 100 MV/cm.
3. The optoelectronic device of claim 1 , wherein
the semiconductor active layer comprises a first region that is adjacent to the first electrode, and a second region that is adjacent to the second electrode, and
at least one of the first region and the second region is a doped region.
4. The optoelectronic device of claim 3 , wherein
when the first electrode is doped with a dopant of a first type, the first region of the semiconductor active layer is doped with a dopant of the first type, and/or
when the second electrode is doped with a dopant of a second type, the second region of the semiconductor active layer is doped with a dopant of the second type.
5. The optoelectronic device of claim 3 , wherein the first and second regions of the semiconductor active layer are apart from each other or in contact with each other.
6. The optoelectronic device of claim 1 , wherein the semiconductor active layer comprises a two-dimensional (2D) semiconductor having a 2D crystal structure.
7. The optoelectronic device of claim 6 , wherein
the 2D semiconductor includes a metal chalcogenide-based material, and
the metal chalcogenide-based material includes a metal element including Mo, W, Nb, V, Ta, Ti, Zr, Hf, Tc, Re, Cu, Ga, In, Sn, Ge, and Pb, and a chalcogen element including S, Se, and Te.
8. The optoelectronic device of claim 1 , wherein the semiconductor active layer comprises a quantum dot.
9. The optoelectronic device of claim 1 , wherein at least one of the first electrode, the second electrode; and the semiconductor active layer comprises a 2D material.
10. The optoelectronic device of claim 1 , wherein the built-in potential of the semiconductor active layer is less than or equal to substantially 5 eV.
11. The optoelectronic device of claim 1 , wherein the optoelectronic device comprises a photodetector or a photovoltaic device.
12. An optoelectronic device comprising:
a first electrode;
a second electrode; and
a semiconductor active layer between the first and second electrodes, the semiconductor active layer being a photodetecting layer,
wherein the semiconductor active layer has a built-in potential of substantially 0.1 eV or greater,
wherein one of the first electrode and the second electrode includes graphene doped with a p-type dopant,
wherein another of the first electrode and the second electrode includes graphene doped with an n-type dopant, and
wherein the optoelectronic device comprises a photodetector, and the photodetector is a self-powered photodetector.
13. The optoelectronic device of claim 1 , further comprising:
a first contact electrode in contact with the first electrode; and
a second contact electrode in contact with the second electrode.
14. The optoelectronic device of claim 13 , wherein the first contact electrode and the second contact electrode are apart from each other in a horizontal direction.
15. The optoelectronic device of claim 13 , wherein the first contact electrode and the second contact electrode are apart from each other in a vertical direction.
16. The optoelectronic device of claim 1 , wherein
the first electrode extends from the semiconductor active layer in a first direction, and
the second electrode extends from the semiconductor active layer in a second direction opposite the first direction.
17. The optoelectronic device of claim 1 , wherein
the first electrode extends from the semiconductor active layer in a first direction, and
the second electrode extends from the semiconductor active layer in a second direction perpendicular to the first direction.
18. The optoelectronic device of claim 1 , wherein
the first electrode, the second electrode, and the semiconductor active layer constitute a unit cell,
the optoelectronic device includes a plurality of unit cells, and further includes a plurality of first contact electrodes respectively connected to first ends of the plurality of unit cells, and a second contact electrode commonly connected to second ends of the plurality of unit cells.
19. An optoelectronic device comprising:
a first electrode;
a second electrode; and
a semiconductor active layer interposed between the first and second electrodes and including at least one of a 2D semiconductor and a quantum dot, the semiconductor active layer being a photodetecting layer,
wherein the semiconductor active layer has a built-in potential of substantially 0.1 eV or greater between the first and second electrodes,
wherein one of the first electrode and the second electrode includes graphene doped with a p-type dopant, and
wherein another of the first electrode and the second electrode includes graphene doped with an n-type dopant.
20. The optoelectronic device of claim 19 , wherein
the semiconductor active layer comprises a first region that is adjacent to the first electrode, and a second region that is adjacent to the second electrode, and
at least one of the first region and the second region is a doped region.
21. The optoelectronic device of claim 20 , wherein
when the first electrode is doped with a dopant of a first type, the first region of the semiconductor active layer is doped with a dopant of the first type, and
when the second electrode is doped with a dopant of a second type, the second region of the semiconductor active layer is doped with a dopant of the second type.
22. The optoelectronic device of claim 19 , wherein
the 2D semiconductor includes a metal chalcogenide-based material, and
the metal chalcogenide-based material includes a metal element from Mo, W, Nb, V, Ta, Ti, Zr, Hf, Tc, Re, Cu, Ga, In, Sn, Ge, and Pb, and a chalcogen element from S, Se, and Te.
23. An optoelectronic device comprising:
a first electrode;
a second electrode; and
a semiconductor active layer between the first and second electrodes, the semiconductor active layer being a photodetecting layer,
wherein at least one of the first electrode and the second electrode includes doped graphene,
wherein the semiconductor active layer has a built-in potential of substantially 0.1 eV or greater, and
wherein the semiconductor active layer comprises a two-dimensional (2D) semiconductor having a 2D crystal structure.
24. The optoelectronic device of claim 23 , wherein
one of the first electrode and the second electrode includes graphene doped with a p-type dopant, and
another of the first electrode and the second electrode includes graphene doped with an n-type dopant.
25. The optoelectronic device of claim 23 , wherein
one of the first electrode and the second electrode includes graphene doped with a p-type dopant or an n-type dopant, and
another of the first electrode and the second electrode includes a metallic material.