Asymmetric high-K dielectric for reducing gate induced drain leakage
View Patent ↗An asymmetric high-k dielectric for reduced gate induced drain leakage in high-k MOSFETs and methods of manufacture are disclosed. The method includes performing an implant process on a high-k dielectric sidewall of a gate structure. The method further includes performing an oxygen annealing process to grow an oxide region on a drain side of the gate structure, while inhibiting oxide growth on a source side of the gate structure adjacent to a source region.
1. A method, comprising:
performing a blocking process on a high-k dielectric material on a source side of a gate structure; and
performing an oxygen annealing process to grow an oxide region on a drain side of the gate structure, while inhibiting oxide growth on the source side of the gate structure adjacent to a source region,
wherein the blocking process comprises a formation of a nitride sidewall on the high-k dielectric material on the source side of a gate structure, and
wherein the blocking process comprises damaging a nitride sidewall on the drain side of the gate structure.
2. The method of claim 1 , wherein the oxide on the source side remains the same during the oxygen annealing process.
3. The method of claim 1 , wherein an angled oxygen implant is performed after spacer formation.
4. The method of claim 1 , further comprising applying a RIE process on the drain side to create a poor encapsulation to enhance regrowth.
5. The method of claim 1 , wherein the gate structure is formed by a gate first process.
6. The method of claim 5 , wherein the gate first process is performed in finFET technologies.
7. The method of claim 1 , wherein the gate structure is formed with a high-k dielectric gate material.
8. The method of claim 7 , further comprising forming an intervening interfacial layer between the high-k dielectric gate material and an underlying substrate.
9. The method of claim 1 , wherein the blocking process comprising forming a mask on the source side, followed by an angled implant of damaging species to damage the nitride sidewall on the drain side.
10. The method of claim 9 , wherein the damaging species is one of oxygen, Germanium, Xenon and Argon on the drain side.
11. The method of claim 9 , wherein the damaging species is an etchant used with reactive ion etching processes on the drain side.
12. The method of claim 9 , further comprising removing the mask followed by a regrowth of oxygen.
13. The method of claim 12 , wherein the removing the mask is performed by a dry process using N 2 H 2 or a wet process.
14. The method of claim 13 , wherein the regrowth of oxygen is formed on a drain side of the gate structure.
15. The method of claim 14 , wherein the regrowth of oxygen is formed adjacent the drain region during a low temperature annealing process.
16. The method of claim 15 , wherein a halo and extension implant process is performed after spacer formation.