Method of fabricating analog capacitor using post-treatment technique

• US 20050196915A1
• Filed: 02/23/2005
• Published: 09/08/2005
• Est. Priority Date: 02/24/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Won, Seok-Jun, Kwon, Dae-Jin, Jeong, Yong-Kuk
• Granted Patent: US 7,288,453 B2
• Time in Patent Office: Days
• US Class Current: 438/238
• CPC Class Codes: H01L 21/02183 the material containing tantalum, e.g. Ta2O5
• CPC Class Codes: H01L 21/02323 introduction of oxygen
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/3211 Nitridation of silicon-containing layers
• CPC Class Codes: H01L 28/40 Capacitors

Abstract

There is provided a method of fabricating an analog capacitor using a post-treatment technique. The method includes forming a lower insulating layer on a semiconductor substrate. A bottom electrode is formed on the lower insulating layer, and a capacitor dielectric layer is formed on the bottom electrode. Then, the capacitor dielectric layer is post-treated in a deoxidizing medium. Then, the post-treated capacitor dielectric layer is post-treated in an oxidizing medium. A top electrode is formed on the post-treated capacitor dielectric layer. The analog capacitor fabricated through the post-treatment as above has a low VCC.

Claims

1. A method of fabricating an analog capacitor comprising:

forming a lower insulating layer on a semiconductor substrate;

forming a bottom electrode on the lower insulating layer;

forming a capacitor dielectric layer on the bottom electrode;

post-treating the capacitor dielectric layer in a deoxidizing medium;

post-treating the post-treated capacitor dielectric layer in an oxidizing medium; and

forming a top electrode on the post-treated capacitor dielectric layer.

2. The method according to claim 1, wherein post-treating the capacitor dielectric layer in a deoxidizing medium is performed using at least one gas selected from the group consisting of H₂, H₂-plasma, N₂, N₂-plasma, NH₃, NH₃-plasma, N₂O, and N₂O-plasma gas.

3. The method according to claim 1, wherein post-treating the capacitor dielectric layer in an oxidizing medium is performed using at least one gas selected from the group consisting of O₂, O₃, and O₂-plasma.

4. The method according to claim 1, further comprising, before forming a capacitor dielectric layer on the bottom electrode, post-treating the bottom electrode in a deoxidizing medium.

5. The method according to claim 4, further comprising, before post-treating the bottom electrode in a deoxidizing medium, post-treating the bottom electrode in an oxidizing medium.

6. The method according to claim 1, wherein forming the capacitor dielectric layer includes depositing a dielectric material using a thermal decomposition technique in a reactant-free state.

7. A method of fabricating an analog capacitor comprising:

forming a lower insulating layer on a semiconductor substrate;

forming a bottom electrode on the lower insulating layer;

forming a lower capacitor dielectric layer on the bottom electrode;

post-treating the lower capacitor dielectric layer in a deoxidizing medium and an oxidizing medium sequentially at least one time;

forming an upper capacitor dielectric layer on the post-treated lower capacitor dielectric layer;

post-treating the upper capacitor dielectric layer in a deoxidizing medium;

post-treating the post-treated upper capacitor dielectric layer in an oxidizing medium; and

forming a top electrode on the post-treated upper capacitor dielectric layer.

8. The method according to claim 7, wherein post-treating the lower capacitor dielectric layer and the upper capacitor dielectric layer in a deoxidizing medium are performed using at least one gas selected from the group consisting of H₂, H₂-plasma, N₂, N₂-plasma, NH₃, NH₃-plasma, N₂O, and N₂O-plasma gas.

9. The method according to claim 7, wherein post-treating the lower capacitor dielectric layer and the upper capacitor dielectric layer in a deoxidizing medium are performed using at least one gas selected from the group consisting of O₂, O₃, and O₂-plasma.

10. The method according to claim 7, further comprising, before forming a lower capacitor dielectric layer on the bottom electrode, post-treating the bottom electrode in a deoxidizing medium.

11. The method according to claim 10, further comprising, before post-treating the bottom electrode in a deoxidizing medium, post-treating the bottom electrode in an oxidizing medium.

12. The method according to claim 7, wherein forming the lower and/or upper capacitor dielectric layer includes depositing a dielectric material using a thermal decomposition technique in a reactant-free state.

13. A method of fabricating an analog capacitor comprising:

forming a lower insulating layer on a semiconductor substrate;

forming a bottom electrode on the lower insulating layer;

forming a capacitor dielectric layer on the bottom electrode;

post-treating the capacitor dielectric layer using NH₃-plasma;

post-treating the post-treated capacitor dielectric layer in an oxidizing medium; and

forming a top electrode on the post-treated capacitor dielectric layer.

14. The method according to claim 13, wherein post-treating the post-treated capacitor dielectric layer in an oxidizing medium is performed using at least one gas selected from the group consisting of O₂, O₃, and O₂-plasma.

15. The method according to claim 13, wherein the bottom electrode and the top electrode are composed of TiN.

16. The method according to claim 13, further comprising, before forming a capacitor dielectric layer, post-treating the bottom electrode using NH₃-plasma gas.

17. The method according to claim 16, further comprising, before post-treating the bottom electrode using NH₃-plasma gas, post-treating the bottom electrode in an oxidizing medium.