Field-effect transistor structure having two-dimensional transition metal dichalcogenide
A field-effect transistor structure having two-dimensional transition metal dichalcogenides includes a substrate, a source/drain structure, a two-dimensional (2D) channel layer, and a gate layer. The source/drain structure is disposed on the substrate and has a surface higher than a surface of the substrate. The 2D channel layer is disposed on the source and the drain and covers the space between the source and the drain. The gate layer is disposed between the source and the drain and covers the 2D channel layer. The field-effect transistor having two-dimensional transition metal dichalcogenides is a planar field-effect transistor or a fin field-effect transistor.
1. A field-effect transistor structure having two-dimensional transition metal dichalcogenides, comprising:
a substrate;
a source/drain structure, disposed on the substrate, having a surface higher than a surface of the substrate, and comprising a source and a drain, wherein an opening is formed between the source and the drain, and the opening separates the source and the drain;
a two-dimensional (2D) channel layer, disposed on the source and the drain and covering a portion of the source/drain structure and a space between the source and the drain, wherein the 2D channel layer does not cover a part of the source and a part of the drain; and
a gate layer, disposed between the source and the drain and covering the 2D channel layer, wherein the field-effect transistor structure having two-dimensional transition metal dichalcogenides is a fin field-effect transistor, the source is connected with the drain by a fin structure, and a width of the source/drain structure is greater than a fin width of the fin structure.
2. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein the gate layer and the 2D channel layer are entirely overlapped.
3. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein the 2D channel layer conformally covers the entire fin structure between the source and the drain, a portion of the drain close to the source and a portion of the source close to the drain.
4. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein a minimum distance between the source and the drain is about 2-15 nanometers.
5. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 4 , wherein the minimum distance is less than 10 nanometers.
6. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein the 2D channel layer has a thickness of about 0.6-5 nanometers.
7. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein the 2D layer comprises a material of one of molybdenum disulfide, tungsten diselenide, tellurium disulfide, and tellurium diselenide.
8. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein the 2D channel layer are entirely overlapped by the gate layer.
9. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , further comprising a high-k dielectric layer formed between the 2D channel layer and the gate layer.
10. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , wherein a material of the fin structure is identical to a material of the substrate.
11. The field-effect transistor structure having two-dimensional transition metal dichalcogenides according to claim 1 , further comprising an oxide layer formed on the surface of the substrate and disposed between the substrate and the 2D channel layer and between the substrate and the fin structure.