Semiconductor structure having dielectric structure extending into second cavity of semiconductor Fin

1. A semiconductor structure, the structure comprising:

a semiconductor fin protruding from a substrate, the semiconductor fin having a first cavity and a second cavity;

a first source/drain region in the first cavity of the semiconductor fin; and

a dielectric structure extending into the second cavity of the semiconductor fin, the dielectric structure comprising:

a first dielectric layer; and

a dielectric liner interposed between the first dielectric layer and the first source/drain region, wherein the first dielectric layer directly contacts a sidewall of the dielectric liner, wherein the first dielectric layer extends further into the semiconductor fin than the dielectric liner.

2. The structure of claim 1 , wherein a depth of the second cavity is greater than a height of the semiconductor fin.

3. The structure of claim 1 , further comprising isolation regions on the substrate, the isolation regions extending along opposing sides of the semiconductor fin.

4. The structure of claim 3 , wherein the dielectric liner contacts a surface of the isolation regions.

5. The structure of claim 3 , wherein a first portion of the dielectric liner is entirely above a top surface of the isolation regions.

6. The structure of claim 5 , wherein the first source/drain region is arranged laterally adjacent to the first portion of the dielectric liner.

7. The structure of claim 3 , wherein an entirety of the dielectric liner is above a top surface of the isolation regions.

8. The structure of claim 1 , wherein a portion of the semiconductor fin is interposed between the first source/drain region and the dielectric liner.

9. The structure of claim 1 , wherein the semiconductor fin includes a third cavity, wherein the second cavity is interposed between the first cavity and the third cavity, and further comprising:

a second source/drain region in the third cavity of the semiconductor fin, wherein the dielectric liner is interposed between the second source/drain region and the first dielectric layer.

10. The structure of claim 1 , wherein the dielectric liner directly contacts the first dielectric layer and the semiconductor fin.

11. The structure of claim 1 , wherein the dielectric liner and the first dielectric layer comprise different materials.

12. A semiconductor structure comprising:

a first semiconductor fin and a second semiconductor fin on a substrate, the first semiconductor fin and the second semiconductor fin being longitudinally aligned;

isolation regions along opposing sides of the first semiconductor fin and the second semiconductor fin;

a first source/drain region in the first semiconductor fin;

a second source/drain region in the second semiconductor fin;

an isolation structure between the first semiconductor fin and the second semiconductor fin, the isolation structure comprising:

a first dielectric liner extending along a first sidewall of the first semiconductor fin and a second sidewall of the second semiconductor fin; and

a dielectric fill on a first sidewall of the first dielectric liner and on a second sidewall of the first semiconductor fin, the first dielectric liner further being on a surface of the first semiconductor fin between the first sidewall of the first semiconductor fin and the second sidewall of the first semiconductor fin, wherein the dielectric fill directly contacts the first semiconductor fin and the second semiconductor fin.

13. The structure of claim 12 , wherein a portion of the first semiconductor fin is interposed between the first source/drain region and the isolation structure, wherein the first dielectric liner extends along a sidewall of the portion of the first semiconductor fin.

14. The structure of claim 13 , further comprising a spacer overlying the portion of the first semiconductor fin.

15. The structure of claim 12 , wherein the dielectric fill directly contacts an upper surface of the isolation regions.

16. The structure of claim 12 , wherein the dielectric fill directly contacts a sidewall of the isolation regions.

17. The structure of claim 12 , wherein an upper surface of the first dielectric liner is level with an upper surface of the dielectric fill.

18. A semiconductor structure comprising:

a first semiconductor fin and a second semiconductor fin on a substrate, the first semiconductor fin and the second semiconductor fin being longitudinally aligned along a first longitudinal axis;

a first gate structure and a second gate structure, the first gate structure and the second gate structure being longitudinally aligned along a second longitudinal axis, wherein the first longitudinal axis intersects the second longitudinal axis;

isolation regions along opposing sides of the first semiconductor fin and the second semiconductor fin;

a first source/drain region in the first semiconductor fin;

a second source/drain region in the second semiconductor fin;

an isolation structure between the first semiconductor fin and the second semiconductor fin, the isolation structure being interposed between the first gate structure and the second gate structure, the isolation structure comprising:

a first dielectric liner extending along a first sidewall of the first semiconductor fin and a second sidewall of the second semiconductor fin, wherein the first dielectric liner directly contacts an upper surface of the isolation regions; and

a dielectric fill on a first sidewall of the first dielectric liner and on a second sidewall of the first semiconductor fin, wherein the first dielectric liner is interposed between the first gate structure and the dielectric fill, wherein the first dielectric liner is interposed between the second gate structure and the dielectric fill.

19. The structure of claim 18 , wherein a longitudinal axis of the isolation structure is aligned along the second longitudinal axis.

20. The structure of claim 18 , wherein an upper surface of the first dielectric liner is level with an upper surface of the dielectric fill.