Post Treatment Methods for Oxide Layers on Semiconductor Devices

• US 20100267248A1
• Filed: 04/19/2010
• Published: 10/21/2010
• Est. Priority Date: 04/20/2009
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Yokota, Yoshitaka, Olsen, Christopher S., Ma, Kai
• Granted Patent: US 9,431,237 B2
• Time in Patent Office: Days
• US Class Current: 438/787
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/02252 formation by plasma treatment, e.g. plasma oxidation of the substrate after treatment of an insulating film by plasma H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/28247 passivation or protection of the electrode, e.g. using re-oxidation
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31654 of semiconductor materials, e.g. the body itself

Abstract

Methods and apparatus for post treating an oxide layer on a semiconductor substrate are disclosed. In one or more embodiments, the oxide layer is formed by thermal oxidation or plasma oxidation and treated with a plasma comprising helium. The helium-containing plasma may also include hydrogen, neon, argon and combinations thereof. In one or more embodiments, a SiO₂ oxide layer is formed on a silicon substrate and treated with a plasma to improve the interface between the silicon substrate and the SiO₂ oxide layer.

Claims

1. A method of treating an oxide layer on a semiconductor substrate, comprising:

placing a substrate on a substrate support having a stack defining a horizontal surface and a sidewall in a reaction chamber;

forming an oxide layer on the stack, the oxide layer having a thickness; and

treating the oxide layer with a post-treatment plasma, selected from a hydrogen plasma, a helium plasma and a neon plasma.

2. The method of claim 1, wherein the post-treatment plasma is formed by introducing a post-treatment gas to the reaction chamber and energizing the post-treatment gas.

3. The method of claim 1, wherein post-treatment gas comprises helium.

4. The method of claim 3, wherein the post-treatment gas further comprises one of hydrogen, neon, argon and combinations thereof.

5. The method of claim 4 wherein the post-treatment gas comprises helium and hydrogen, the helium comprising at least 50% of the post-treatment gas.

6. The method of claim 4, wherein the post-treatment gas comprises helium and neon, the helium comprising at least 50% of the post-treatment gas.

7. The method of claim 2, wherein the post-treatment gas comprises helium and argon, the helium comprising at least 50% of the post-treatment gas.

8. The method of claim 1, wherein the substrate comprises silicon and the oxide layer comprises silicon dioxide and treating the substrate provides a substrate with an improved interface between the silicon and silicon dioxide.

9. The method of claim 1, further comprising annealing the oxide layer.

10. A method of treating an oxide layer on a semiconductor substrate, comprising:

placing a substrate including a stack defining a horizontal surface and a sidewall on a substrate support in a reaction chamber;

forming an oxide layer on the stack, the oxide layer having a thickness; and

treating the oxide layer with a helium-containing plasma to change a property of the oxide layer.

11. The method of claim 10, wherein the oxide layer is formed at a temperature above 700′

C.

12. The method of claim 11, further comprising removing the substrate from the reaction chamber and placing the substrate in a plasma reaction chamber before treating the oxide layer with a helium-containing plasma.

13. The method of claim 12, wherein the post-treatment plasma is formed by introducing a helium-containing gas to the plasma reaction chamber and energizing the helium-containing gas.

14. The method of claim 13, wherein the helium-containing gas further comprises one of hydrogen, neon, argon and combinations thereof.

15. The method of claim 10, further comprising annealing the oxide layer.

16. The method of claim 12, wherein the substrate is removed from the reaction chamber and placed in a plasma reaction chamber under vacuum conditions.

17. The method of claim 10, wherein the substrate comprises silicon and the oxide layer comprises silicon dioxide and treating the substrate provides a substrate with an improved interface between the silicon and silicon dioxide.

18. The method of claim 10, wherein treating the oxide layer with a helium-containing plasma improves the oxygen content of the oxide layer.

19. The method of claim 18, wherein the oxygen content of the oxide layer is in an amount in the range from about 65% to about 73%.

20. The method of claim 16, wherein treating the oxide layer with a helium-containing plasma reduces changes in the thickness of the oxide layer when exposing to high temperature.