Semiconductor device with isolation trench liner
A semiconductor device includes a layer of semiconductor material having an active transistor region defined therein, an isolation trench formed in the semiconductor material adjacent the active transistor region, and a trench liner lining the isolation trench, wherein the trench liner is formed from a material that substantially inhibits formation of high-k material thereon, and wherein the isolation trench and the trench liner together form a lined trench. The device has an insulating material in the lined trench, and high-k gate material overlying at least a portion of the insulating material and overlying at least a portion of the active transistor region, such that the trench liner divides and separates the high-k gate material overlying the at least a portion of the insulating material from the high-k gate material overlying the at least a portion of the active transistor region.
1. A semiconductor device comprising:
a layer of semiconductor material having an active transistor region defined therein;
an isolation trench formed in the layer of semiconductor material adjacent to the active transistor region;
a trench liner lining the isolation trench, wherein the trench liner is formed from a material that substantially inhibits formation of high-k material thereon, and wherein the isolation trench and the trench liner together form a lined trench;
an insulating material in the lined trench; and
a high-k gate material overlying at least a portion of the insulating material and overlying at least a portion of the active transistor region, wherein the trench liner creates a discontinuity in the high-k gate material between a portion of the high-k gate material overlying the portion of the insulating material and a portion of the high-k gate material overlying the portion of the active transistor region.
2. The semiconductor device of claim 1 ,
wherein the trench liner divides and separates the high-k gate material overlying the at least a portion of the insulating material from the high-k gate material overlying the at least a portion of the active transistor region.
3. The semiconductor device of claim 2 , wherein the trench liner forms an oxygen barrier between the high-k gate material overlying the portion of the insulating material and the high-k gate material overlying the portion of the active transistor region.
4. The semiconductor device of claim 2 , wherein:
the trench liner includes an upper rim; and
the upper rim is substantially void of the high-k gate material.
5. The semiconductor device of claim 2 , further comprising:
a metal gate layer overlying the high-k gate material and overlying the trench liner;
and a polysilicon gate layer overlying the metal gate layer.
6. The semiconductor device of claim 2 , wherein the trench liner is formed from a nitride material.
7. The semiconductor device of claim 2 , wherein the insulating material is an oxide material.
8. The semiconductor device of claim 1 , wherein the trench liner separates the high-k gate material overlying the at least a portion of the insulating material from the high-k gate material overlying the at least a portion of the active transistor region.
9. The semiconductor device of claim 1 , wherein the trench liner forms an oxygen barrier between the high-k gate material overlying the portion of the insulating material and the high-k gate material overlying the portion of the active transistor region.
10. The semiconductor device of claim 1 , wherein:
the trench liner includes an upper rim; and
the upper rim is substantially void of the high-k gate material.
11. The semiconductor device of claim 1 , further comprising:
a metal gate layer overlying the high-k gate material and overlying the trench liner;
and a polysilicon gate layer overlying the metal gate layer.
12. The semiconductor device of claim 1 , wherein the trench liner is formed from a nitride material.
13. The semiconductor device of claim 1 ,
wherein the trench liner forms an oxygen barrier between the high-k gate material overlying the portion of the insulating material and the high-k gate material overlying the portion of the active transistor region.
14. The semiconductor device of claim 13 , wherein the trench liner separates the high-k gate material overlying the at least a portion of the insulating material from the high-k gate material overlying the at least a portion of the active transistor region.
15. The semiconductor device of claim 2 , wherein the trench liner forms an oxygen barrier between the high-k gate material overlying the portion of the insulating material and the high-k gate material overlying the portion of the active transistor region.
16. The semiconductor device of claim 13 , wherein:
the trench liner includes an upper rim; and
the upper rim is substantially void of the high-k gate material.
17. The semiconductor device of claim 13 , further comprising:
a metal gate layer overlying the high-k gate material and overlying the trench liner;
and a polysilicon gate layer overlying the metal gate layer.
18. The semiconductor device of claim 13 , wherein the trench liner is formed from a nitride material.