Superlattice structure including two-dimensional material and device including the superlattice structure
Provided are a superlattice structure including a two-dimensional material and a device including the superlattice structure. The superlattice structure may include at least two different two-dimensional (2D) materials bonded to each other in a lateral direction, and an interfacial region of the at least two 2D materials may be strained. The superlattice structure may have a bandgap adjusted by the interfacial region that is strained. The at least two 2D materials may include first and second 2D materials. The first 2D material may have a first bandgap in an intrinsic state thereof. The second 2D material may have a second bandgap in an intrinsic state thereof. An interfacial region of the first and second 2D materials and an adjacent region may have a third bandgap between the first bandgap and the second bandgap.
1. A lateral two-dimensional (2D) superlattice structure, comprising:
at least two 2D materials that are different from each other and coherently bonded to each other in a lateral direction,
an interfacial region of the at least two 2D materials being strained,
the lateral 2D superlattice structure having a bandgap adjusted by the interfacial region that is strained such that a bandgap of the interfacial region is between a first bandgap of a first 2D material and a second bandgap of a second 2D material among the at least two 2D materials that are different from each other, the first 2D material and the second 2D material being coherently bonded to each other at the interfacial region, wherein
the first 2D material is a first 2D transition metal dichalcogenide (TMDC) material,
the second 2D material is a second 2D TMDC material,
the first 2D TMDC material has the first bandgap in an intrinsic state thereof,
the second 2D TMDC material has the second bandgap in an intrinsic state thereof,
the bandgap of the interfacial region and an adjacent region have a third bandgap that is between the first bandgap and the second bandgap,
the interfacial region of the at least two 2D materials has a lattice mismatch of 10% or less, and
the interfacial region has a bandgap variation rate of 30% or less with respect to one of the at least 2D materials.
2. The lateral 2D superlattice structure of claim 1 , wherein the first 2D TMDC material and the second 2D TMDC material have a same transition metal element or a same chalcogen element.
3. The lateral 2D superlattice structure of claim 1 , wherein
the interfacial region does not include dislocations or includes 1% or less dislocations.
4. The lateral 2D superlattice structure of claim 1 , wherein
the interfacial region of the at least two 2D materials has 10% or less strain due to the lattice mismatch.
5. The lateral 2D superlattice structure of claim 1 , wherein
one or more of the at least two 2D materials include a metal atom among Mo, W, Nb, V, Ta, Ti, Zr, Hf, Tc, Re, Cu, Ga, In, Sn, Ge, or Pb, and a chalcogenide atom among S, Se, or Te.
6. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure has a structure, in which two kinds of 2D materials are alternately and repeatedly arranged or three kinds of 2D materials are periodically arranged.
7. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure has two or more kinds of 2D materials that are arranged to have a uniform width, a uniform ratio, or both the uniform width and the uniform ratio.
8. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure includes two or more kinds of 2D materials that are arranged to have different widths in the lateral direction according to locations thereof, different width ratios in the lateral direction from each other according to locations thereof, or both different widths in the lateral direction and different width ratios in the lateral direction from each other according to locations thereof.
9. The lateral 2D superlattice structure of claim 1 , comprising;
a first region of the lateral 2D superlattice structure includes the first 2D material and the second 2D material bonded to each other at a first width ratio in the lateral direction,
a second region of the lateral 2D superlattice structure includes the first 2D material and the second 2D material bonded to each other at a second width ratio in the lateral direction that is different from the first width ratio in the lateral direction,
wherein
the first region has a first adjusted bandgap, and
the second region has a second adjusted bandgap that is different from the first adjusted bandgap.
10. The lateral 2D superlattice structure of claim 1 , wherein
the at least two 2D materials included in the lateral 2D superlattice structure each have a width of 1000 nm or less.
11. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure has a triangle shape or a square shape when seen from above.
12. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure includes a P—N—P bonding structure, an N—P—N bonding structure, a P + —P—P + bonding structure, an N + —N—N + bonding structure, or a combination thereof.
13. The lateral 2D superlattice structure of claim 1 , wherein
the lateral 2D superlattice structure includes a plurality of regions having different bandgaps from one another.
14. A two-dimensional (2D) material-containing device, comprising:
the lateral 2D superlattice structure of claim 1 ; and
at least one electrode member connected to the lateral 2D superlattice structure.
15. The 2D material-containing device of claim 14 , wherein
the 2D material-containing device includes an electronic device.
16. The 2D material-containing device of claim 14 , wherein
the 2D material-containing device includes an optical device.
17. The 2D material-containing device of claim 14 , wherein
the 2D material-containing device includes at least one of a diode type device or a transistor type device.
18. The 2D material-containing device of claim 14 , comprising:
a first electrode element connected to a first region of the lateral 2D superlattice structure;
a second electrode element connected to a second region of the lateral 2D superlattice structure; and
a connecting element between the lateral 2D superlattice structure and the second electrode element for connecting the lateral 2D superlattice structure to the second electrode element.
19. The 2D material-containing device of claim 14 , wherein
the lateral 2D superlattice structure includes a plurality of first 2D material regions and a plurality of second 2D material regions that are alternately arranged,
the 2D material-containing device further includes a first electrode structure connected to the plurality of first 2D material regions, and
the 2D material-containing device further includes a second electrode structure connected to the plurality of second 2D material regions.
20. The 2D material-containing device of claim 14 , further comprising:
a first gate structure; and
a second gate structure, wherein
the lateral 2D superlattice structure includes an N-channel region and a P-channel region, and
the first gate structure is on the N-channel region, and
the second gate structure is on the P-channel region.