Negative capacitance gate-all-around transistor with tunable capacitance ratio
A semiconductor structure is provided that includes a tunable and shared non-conductive layer as part of a gate stack of at least a pair of nanosheet GAA transistors with a shared metal gate electrode. The semiconductor structure has a tunable non-conductive material/gate dielectric area ratio where the non-conductive material is not constrained to a periphery of the nanosheet stack cross section.
1 . A semiconductor structure comprising:
a first gate-all-around (GAA) transistor located in a first active area and a second GAA transistor located in a second active area, wherein the first GAA transistor and the second GAA transistor comprise a shared gate structure in series with a shared non-conductive layer;
a metal electrode contacting the shared non-conductive layer, wherein the metal electrode has a same width as the shared non-conductive layer; and
a gate contact structure contacting the metal electrode.
2 . The semiconductor structure of claim 1 , wherein the shared non-conductive layer entirely covers the shared gate structure located above an uppermost semiconductor channel material nanosheet of the first GAA transistor, and entirely covers the shared gate structure located above an uppermost semiconductor channel material nanosheet of the second GAA transistor.
3 . The semiconductor structure of claim 2 , wherein the shared non-conductive layer further covers an entirety of the shared gate structure that is present between the first active area and the second active area.
4 . The semiconductor structure of claim 1 , wherein the shared non-conductive layer partially covers the shared gate structure located above an uppermost semiconductor channel material nanosheet of the first GAA transistor, and partially covers the shared gate structure located above an uppermost semiconductor channel material nanosheet of the second GAA transistor.
5 . The semiconductor structure of claim 4 , wherein the shared non-conductive layer covers an entirety of the shared gate structure that is present between the first active area and the second active area.
6 . The semiconductor structure of claim 1 , wherein the shared non-conductive layer is located entirely in an area between the first active area and the second active area and is spaced apart from inner facing sidewalls of the shared gate structure of both the first GAA transistor and the second GAA transistor.
7 . The semiconductor structure of claim 1 , wherein the semiconductor structure has a non-conductive material to gate dielectric area ratio that is less than 1.
8 . The semiconductor structure of claim 1 , wherein the shared non-conductive layer extends an entire width of the shared gate structure.
9 . The semiconductor structure of claim 8 , wherein the semiconductor structure has a non-conductive material to gate dielectric area ratio that is at a maximum.
10 . The semiconductor structure of claim 1 , wherein the shared non-conductive layer comprises a ferroelectric material, an antiferroelectric material, or a combination thereof.
11 . The semiconductor structure of claim 1 , wherein the first GAA transistor and the second GAA transistor are located on a surface of an insulator layer that is located on a semiconductor substrate.
12 . The semiconductor structure of claim 11 , wherein the shared gate structure that is located between the first active area and the second active area is capacitively coupled to the insulator layer.
13 . The semiconductor structure of claim 1 , wherein the first GAA transistor and the second GAA transistor are located on a surface of a semiconductor substrate.
14 . The semiconductor structure of claim 13 , wherein the shared gate structure that is located between the first active area and the second active area is capacitively coupled to the semiconductor substrate.
15 . The semiconductor structure of claim 1 , wherein the gate contact structure which contacts the metal electrode is located in an area between the first active area and the second active area.
16 . The semiconductor structure of claim 1 , wherein the gate contact structure which contacts the metal electrode is located on top of the first active area or the second active area.
17 . The semiconductor structure of claim 1 , wherein the first GAA transistor is of a different conductivity type than the second GAA transistor.
18 . The semiconductor structure of claim 1 , wherein each of the first GAA transistor and the second GAA transistor includes source/drain regions.
19 . The semiconductor structure of claim 18 , wherein a first source/drain region of the source/drain regions comprises a semiconductor material and a dopant, and a second source/drain region of the source/drain regions is a metallic source/drain region.
20 . The semiconductor structure of claim 18 , wherein each of the source/drain regions are comprised of metal.