Gate stack formed with interrupted deposition processes and laser annealing

Patent metadata

Field	Value
Publication number	US-9613870-B2
Application number	US-201514755829-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Jun 30, 2015
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

Semiconductor structures and methods of fabricating the same using interrupted deposition processes and multiple laser anneals are provided. The structure includes a high-k gate stack with a high-k bilayer or nanolaminate where a bottom portion of the bilayer is crystallized while a top portion of the bilayer is amorphous.

First claim

What is claimed:

1. A structure, comprising:
a high-k gate dielectric stack with a high-k bilayer or nanolaminate where a bottom portion of the bilayer is crystallized while a top portion of the bilayer is amorphous;
a blocking layer deposited on a pFET side of the high-k dielectric stack; and
a lanthanum oxide film deposited on the blocking material and an exposed portion of the high-k bilayer or nanolaminate on a nFET side of the high-k dielectric stack.

2. The structure of claim 1 , wherein crystallites of the crystallized high-k bilayer is below 2 nm.

3. The structure of claim 2 , wherein a thickness of the crystallized portion of the high-k bilayer is less than 12 Å.

4. The structure of claim 3 , wherein the high-k bilayer contains La or Mg atoms.

5. The structure of claim 4 , wherein an amount of atoms of the La or Mg atoms is larger than 1.5e14 atoms/cm 2 .

6. The structure of claim 4 , further comprising multiple nFET transistors where at least one of the nFET transistors has the La or Mg atoms.

7. The structure of claim 6 , wherein the at least one of the nFET transistors with the La or Mg atoms have threshold voltages separated by at least 100 mV.

8. The structure of claim 6 , wherein the nFET transistors with the La or Mg atoms have threshold voltages separated by at least 100 mV.

9. The structure of claim 6 , wherein the La or Mg atoms will form dipoles by binding with oxygen.

10. The structure of claim 1 , further comprising multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer.

11. The structure of claim 10 , wherein the multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer comprise La or Mg doping.

12. The structure of claim 1 , wherein the blocking material comprises at least TiN or a or a composite sandwich of TiN/oxide/TiN.

13. The structure of claim 12 , wherein a thickness of the blocking material is less than 50 Å.

14. The structure of claim 1 , further comprising a capping layer formed over the lanthanum oxide film on the nFET transistor side.

15. The structure of claim 14 , further comprising an a-Si capping layer deposited on the capping layer.

16. The structure of claim 15 , wherein a thickness of the a-Si capping layer is less than 20 Å.

17. The structure of claim 1 , further comprising multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer.

18. The structure of claim 17 , wherein the multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer comprise La or Mg doping.

19. The structure of claim 18 , wherein the multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer comprise La or Mg doping of different levels.

20. A structure, comprising:
a high-k gate dielectric stack with a high-k bilayer or nanolaminate where a bottom portion of the bilayer is crystallized while a top portion of the bilayer is amorphous; and
multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer,
wherein the multiple nFET transistors with the high-k dielectric gate stack with the high-k bilayer comprise La or Mg doping of different levels.

Assignees

• IBM

Inventors

• Ando Takashi
• Dasgupta Aritra
• Gluschenkov Oleg
• Kannan Balaji
• Kwon Unoh

Classifications

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P34/42

  with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) · CPC title

• H10P14/69395

  the material containing zirconium, e.g. ZrO2 · CPC title

• H10P14/69392

  the material containing hafnium, e.g. HfO2 · CPC title

• H10P14/6544

  to change the morphology of the insulating materials, e.g. transformation of an amorphous layer into a crystalline layer · CPC title