Lateral oxidation with high-K dielectric liner
View Patent ↗Disclosed are methods of making and using a high-K dielectric liner to facilitate the lateral oxidation of a high-K gate dielectric, integrated circuit structures containing the high-K dielectric liner and/or oxidized high-K gate dielectric, and other associated methods.
1. A method of oxidizing a high-K gate dielectric in an integrated circuit structure, comprising:
forming a high-K dielectric liner over a FET, the FET comprising a metal gate and the high-K gate dielectric, the high-K dielectric liner in contact with the high-K gate dielectric to allow oxygen from the high-K dielectric liner to oxidize the high-K gate dielectric,
wherein the high-K dielectric liner is annealed at a temperature from about 100° C. to about 400° C. and the high-K dielectric liner comprises one of HfO 2 , ZrO 2 , Hf x Si 1-x O 2 , Hf x La 1-x O 2 , Zr x Si 1-x O 2 , La x Si 1-x O 2 , Gd x Si 1-x O 2 , HfZrSiO, HfLaSiO, or HfGdSiO, where x is between 0 and 1.
2. The method of claim 1 comprised in a gate first CMOS process.
3. The method of claim 1 , wherein the high-K dielectric liner has a thickness from about 1 nm to about 100 nm.
4. The method of claim 1 , wherein the high-K dielectric liner is annealed at a temperature from about 150° C. to about 350° C.
5. The method of claim 1 , wherein the high-K dielectric liner is formed in an atmosphere comprising from about 10 ppm by volume to about 100% by volume oxygen.
6. The method of claim 1 further comprising removing the high-K dielectric liner from over the FET.
7. The method of claim 6 , before removing the high-K dielectric liner, keeping the high-K dielectric liner in contact with the high-K gate dielectric for a time from about 10 seconds to about 5 minutes.
8. The method of claim 1 further comprising forming a silicon nitride liner over the high-K dielectric liner to mitigate out diffusion of oxygen from the high-K dielectric liner.
9. The method of claim 1 , with the proviso that the high-K dielectric liner does not comprise HfSiON.
10. A method of reducing Vth of a pFET comprising a high-K gate dielectric, comprising:
forming a high-K dielectric liner over the pFET, the pFET comprising a metal gate and the high-K gate dielectric, the high-K dielectric liner in contact with the high-K gate dielectric to allow oxygen from the high-K dielectric liner to oxidize the high-K gate dielectric,
wherein the high-K dielectric liner is annealed at a temperature from about 100° C. to about 400° C. and the high-K dielectric liner comprises one of HfO 2 , ZrO 2 , Hf x Si 1-x O 2 , Hf x La 1-x O 2 , Zr x Si 1-x O 2 , La x Si 1-x O 2 , Gd x Si 1-x O 2 , HfZrSiO, HfLaSiO, or HfGdSiO, where x is between 0 and 1.
11. The method of claim 10 , wherein the high-K dielectric liner is formed in an atmosphere comprising from about 10% by volume to about 90% by volume oxygen, and keeping the high-K dielectric liner in contact with the high-K gate dielectric for a time from about 10 seconds to about 5 minutes.
12. The method of claim 10 , wherein the high-K dielectric liner has a thickness from about 1 nm to about 100 nm.
13. The method of claim 10 , wherein the high-K dielectric liner comprises HfO 2 .
14. A method of oxidizing a high-K gate dielectric in an integrated circuit structure, comprising:
forming a high-K dielectric liner over a FET, the FET comprising a metal gate and the high-K gate dielectric, the high-K dielectric liner in contact with the high-K gate dielectric to allow oxygen from the high-K dielectric liner to oxidize the high-K gate dielectric,
wherein the high-K dielectric liner is formed in an atmosphere comprising from about 10 ppm by volume to about 100% by volume oxygen.
15. The method of claim 14 , wherein the high-K dielectric liner is annealed at a temperature from about 100° C. to about 400° C.
16. The method of claim 14 , wherein the high-K dielectric liner is formed in an atmosphere comprising from about 10% by volume to about 90% by volume oxygen.
17. The method of claim 14 further comprising removing the high-K dielectric liner from over the FET.
18. The method of claim 17 , before removing the high-K dielectric liner, keeping the high-K dielectric liner in contact with the high-K gate dielectric for a time from about 10 seconds to about 5 minutes.