Double diffusion break gate structure without vestigial antenna capacitance
A double diffusion break (DDB) gate structure is provided by removing the vestigial antenna to provide a space and the space is filled, at least in part, with an interlevel dielectric (ILD) material. Removal of the vestigial antenna from the DDB gate structure will reduce the device capacitance and improve device performance, while enabling DDB in tight integration schemes.
1. A semiconductor structure comprising:
a double diffusion break region located between a first device region and a second device region, wherein the double diffusion break region includes a sacrificial gate material and wherein an interlevel dielectric material is present adjacent to each side of the sacrificial gate material and beneath at least a portion of the sacrificial gate material.
2. The semiconductor structure of claim 1 , wherein the interlevel dielectric material is present entirely beneath the sacrificial gate material.
3. The semiconductor structure of claim 2 , wherein the interlevel dielectric material has a topmost surface that is coplanar with a topmost surface of the sacrificial gate material.
4. The semiconductor structure of claim 1 , wherein the interlevel dielectric material is present partially beneath the sacrificial gate material.
5. The semiconductor structure of claim 4 , wherein a void is located beneath the sacrificial gate material and the void is surrounded on either side by portions of the interlevel dielectric material.
6. The semiconductor structure of claim 5 , wherein the interlevel dielectric material has a topmost surface that is coplanar with a topmost surface of the sacrificial gate material.
7. The semiconductor structure of claim 1 , further comprising a gate spacer positioned between each sidewall surface of the sacrificial gate material and a portion of the interlevel dielectric material.
8. The semiconductor structure of claim 1 , wherein the interlevel dielectric material on each side of the sacrificial gate material extends below a topmost surface of a substrate.
9. The semiconductor structure of claim 1 , wherein the sacrificial gate material is composed of polysilicon.
10. The semiconductor structure of claim 1 , wherein no silicon fin is present beneath the sacrificial gate material.