Transistor isolation regions and methods of forming the same

1. A method comprising:

etching a trench in a substrate;

depositing a liner material in the trench with an atomic layer deposition process;

depositing a flowable material on the liner material and in the trench with a contouring flowable chemical vapor deposition process;

converting the liner material and the flowable material to a solid insulation material, a portion of the trench remaining unfilled by the solid insulation material;

forming a hybrid fin in the portion of the trench unfilled by the solid insulation materials; and

recessing the solid insulation material so that the hybrid fin protrudes above the solid insulation material.

2. The method of claim 1 , wherein the contouring flowable chemical vapor deposition process has a first deposition rate along vertical surfaces of the trench, the contouring flowable chemical vapor deposition process has a second deposition rate along horizontal surfaces of the trench, and the first deposition rate is substantially equal to the second deposition rate.

3. The method of claim 1 , wherein the flowable material is formed of silicon oxynitride, and the contouring flowable chemical vapor deposition process comprises:

exposing the liner material to trisilylamine, oxygen gas, and ammonia simultaneously.

4. The method of claim 3 , wherein the liner material is formed of silicon nitride, and the atomic layer deposition process comprises:

performing an atomic layer deposition cycle by exposing the substrate to silane and ammonia cyclically; and

repeating the atomic layer deposition cycle a number of times.

5. The method of claim 3 , wherein exposing the liner material to trisilylamine, oxygen gas, and ammonia comprises:

placing the substrate in a deposition chamber;

dispensing trisilylamine in the deposition chamber at a first flow rate in a range of 900 sccm to 1410 sccm;

dispensing oxygen gas in the deposition chamber at a second flow rate in a range of 10 sccm to 100 sccm; and

dispensing ammonia in the deposition chamber at a third flow rate in a range of 20 sccm to 100 sccm,

wherein a ratio of the first flow rate to the third flow rate is at least 10.

6. The method of claim 5 , wherein exposing the liner material to trisilylamine, oxygen gas, and ammonia further comprises:

generating a plasma in the deposition chamber,

wherein the deposition chamber is maintained at a pressure of less than 600 Torr, and

wherein the deposition chamber is maintained at a temperature in a range of 10° C. to 135° C.

7. The method of claim 1 , wherein the solid insulation material is silicon oxide, and wherein converting the liner material and the flowable material to the solid insulation material comprises:

annealing the liner material and the flowable material while exposing the liner material and the flowable material to steam.

8. The method of claim 7 , wherein annealing the liner material and the flowable material comprises annealing the liner material and the flowable material at a temperature in a range of 400° C. to 700° C. and for a duration in a range of 1 hour to 6 hours.

9. A method comprising:

etching a first trench and a second trench in a substrate, the first trench having a first width, the second trench having a second width, the second width greater than the first width;

depositing a flowable material in the first trench and the second trench;

converting the flowable material to a solid insulation material, the solid insulation material filling the first trench, the solid insulation material lining the second trench;

forming a hybrid fin on the solid insulation material in the second trench, the hybrid fin filling portions of the second trench that are unfilled by the solid insulation material; and

recessing the solid insulation material to form a first isolation region in the first trench and to form a second isolation region in the second trench, the hybrid fin protruding above the second isolation region.

10. The method of claim 9 , wherein the portions of the second trench that are unfilled by the solid insulation material have a third width in a range of 50 nm to 100 nm.

11. The method of claim 9 , wherein the flowable material is deposited to a first thickness in the second trench, the first thickness being substantially uniform along sidewalls and a bottom surface of the second trench.

12. The method of claim 11 , wherein the first width is in a range of 5 nm to 12 nm, the second width is in a range of 15 nm to 40 nm, the first thickness is in a range of 10 nm to 15 nm, and a ratio of the first thickness to the second width is in a range of 20% to 100%.

13. The method of claim 9 , wherein the first trench has a first depth, the second trench has a second depth, and the second depth is greater than the first depth.

14. A method comprising:

etching a first trench and a second trench in a substrate, the first trench having a first width, the second trench having a second width, the second width greater than the first width;

depositing a liner material in the first trench and the second trench with an atomic layer deposition process;

depositing a flowable material on the liner material and in the first trench and the second trench with a contouring flowable chemical vapor deposition process;

converting the liner material and the flowable material to a solid insulation material, the solid insulation material filling the first trench, the solid insulation material lining the second trench, a portion of the second trench remaining unfilled by the solid insulation material;

forming a hybrid fin in the portion of the second trench unfilled by the solid insulation material; and

recessing the solid insulation material to form a first isolation region in the first trench and to form a second isolation region in the second trench, the hybrid fin protruding above the second isolation region.

15. The method of claim 14 , wherein the contouring flowable chemical vapor deposition process has a first deposition rate along vertical surfaces, the contouring flowable chemical vapor deposition process has a second deposition rate along horizontal surfaces, and the first deposition rate is substantially equal to the second deposition rate.

16. The method of claim 14 , wherein the flowable material is formed of silicon oxynitride, and the contouring flowable chemical vapor deposition process comprises:

exposing the liner material to trisilylamine, oxygen gas, and ammonia simultaneously.

17. The method of claim 14 , wherein the solid insulation material is silicon oxide, and wherein converting the liner material and the flowable material to the solid insulation material comprises:

annealing the liner material and the flowable material while exposing the liner material and the flowable material to steam.

18. The method of claim 14 , wherein the first trench has a first depth, the second trench has a second depth, and the second depth is greater than the first depth.

19. The method of claim 14 , the hybrid fin having a first curved bottom surface with a first arc length, the second isolation region having a second curved bottom surface with a second arc length, the second arc length less than the first arc length.

20. The method of claim 14 , further comprising:

forming a gate structure on the hybrid fin.