High pressure annealing of metal gate structures

• US 10,636,705 B1
• Filed: 11/29/2018
• Issued: 04/28/2020
• Est. Priority Date: 11/29/2018
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Wang, Yifei, Leschkies, Kurtis, Wang, Fei, Liu, Xin, Tang, Wei, Yang, Yixiong, Liu, Wenyi, Godet, Ludovic
• Primary Examiner(s): Smith, Zandra V
• Assistant Examiner(s): Parker, John M
• Application Number:
  US16/204,560
• Time in Patent Office: 516 Days
• CPC Class Codes: H01L 21/02244 of a metallic layer
• CPC Class Codes: H01L 21/28079 the final conductor layer next to the insulator being a single metal, e.g. Ta, W, Mo, Al
• CPC Class Codes: H01L 21/28088 the final conductor layer next to the insulator being a composite, e.g. TiN
• CPC Class Codes: H01L 21/28097 the final conductor layer next to the insulator being a metallic silicide
• CPC Class Codes: H01L 21/762 Dielectric regions , e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/7685 the layer covering a conductive structure H01L21/76849 takes precedence
• CPC Class Codes: H01L 21/76856 by treatment in plasmas or gaseous environments, e.g. nitriding a refractory metal liner
• CPC Class Codes: H01L 21/76868 Forming or treating discontinuous thin films, e.g. repair, enhancement or reinforcement of discontinuous thin films
• CPC Class Codes: H01L 21/76882 Reflowing or applying of pressure to better fill the contact hole
• CPC Class Codes: H01L 21/76883 Post-treatment or after-treatment of the conductive material
• CPC Class Codes: H01L 21/76888 By rendering at least a portion of the conductor non conductive, e.g. oxidation

Abstract

The method of treating a film stack includes depositing a barrier film containing a metal into a via formed within a dielectric layer disposed on a substrate and depositing a metal contact on the barrier film within the via, where a void is located within the barrier film or between the barrier film and the metal contact. The method also includes exposing the metal contact and the barrier film to an oxidizing agent at a temperature of less than 400° C. and at a pressure of about 20 bar to about 100 bar within a process chamber to produce a metal oxide within the void.

Claims

1. A method of treating a film stack, comprising:

depositing a barrier film comprising a metal into a via formed within a dielectric layer disposed on a substrate;

depositing a metal contact on the barrier film within the via, wherein a void is located between two barrier layers contained within the barrier film; and

exposing the metal contact and the barrier film to an oxidizing agent at a temperature of less than 400°

C. and at a pressure of about 20 bar to about 100 bar within a process chamber to produce a metal oxide within the void.

2. The method of claim 1, wherein the oxidizing agent diffuses through holes within the barrier film to reach the void.

3. The method of claim 1, wherein the void is filled with the metal oxide to produce a sealed seam.

4. The method of claim 1, wherein the metal oxide comprises the metal contained in the barrier film.

5. The method of claim 4, wherein the metal oxide comprises titanium oxide, tantalum oxide, tungsten oxide, titanium oxynitride, tantalum oxynitride, tungsten oxynitride, alloys thereof, or any combination thereof.

6. The method of claim 1, wherein the temperature of the process chamber is about 25°

C. to about 380°

C. when the metal contact and the barrier film are exposed to the oxidizing agent.

7. The method of claim 1, wherein the temperature of the process chamber is about 100°

C. to about 350°

C. when the metal contact and the barrier film are exposed to the oxidizing agent.

8. The method of claim 1, wherein the pressure of the process chamber is about 25 bar to about 80 bar when the metal contact and the barrier film are exposed to the oxidizing agent.

9. The method of claim 8, wherein the pressure of the process chamber is about 30 bar to about 60 bar.

10. The method of claim 1, wherein the oxidizing agent comprises water, steam, oxygen gas (O₂), oxygen plasma, ozone, hydrogen peroxide, or any combination thereof.

11. The method of claim 1, wherein the barrier film comprises one layer of titanium, titanium nitride, titanium silicide nitride, titanium aluminum alloy, titanium aluminide, tantalum, tantalum nitride, tantalum silicide nitride, tungsten, tungsten nitride, tungsten silicide nitride, alloys thereof, or any combination thereof.

12. The method of claim 1, wherein the metal contact comprises tungsten, copper, cobalt, alloys thereof, or any combination thereof.

13. The method of claim 1, wherein a damascene structure comprising the barrier film and the metal contact has an aspect ratio of about 2 to about 100.

14. A method of treating a film stack, comprising:

depositing a barrier film comprising a metal into a via located on a substrate;

depositing a metal contact on the barrier film within the via, wherein a void is located within the barrier film or between the barrier film and the metal contact;

exposing the metal contact and the barrier film to an oxidizing agent at a temperature of less than 400°

C. and at a pressure of about 20 bar to about 100 bar within a process chamber to produce a metal oxide within the void; and

then

exposing the metal contact and the barrier film to an annealing gas a temperature of less than 400°

C. and at a pressure of about 20 bar to about 100 bar within the process chamber, wherein the annealing gas comprises nitrogen gas (N₂), ammonia, hydrogen gas (H₂), or a mixture thereof.

15. The method of claim 14, wherein the temperature of the process chamber is about 25°

C. to about 380°

C. and at a pressure of about 25 bar to about 80 bar when the metal contact and the barrier film are exposed to the oxidizing agent.

16. The method of claim 14, wherein the temperature of the process chamber is about 100°

C. to about 350°

C. and at a pressure of about 30 bar to about 60 bar when the metal contact and the barrier film are exposed to the oxidizing agent.

17. A method of treating a film stack, comprising:

depositing a barrier film comprising a metal into a via formed within a dielectric layer disposed on a substrate;

depositing a metal contact on the barrier film within the via, wherein a void is located within the barrier film or between the barrier film and the metal contact; and

exposing the metal contact and the barrier film to an oxidizing agent at a temperature of less than 400°

C. and at a pressure of about 20 bar to about 100 bar within a process chamber to produce a metal oxide within the void; and

then

exposing the metal contact and the barrier film to an annealing gas at a temperature of less than 400°

C. and at a pressure of about 20 bar to about 60 bar within the process chamber, wherein the annealing gas comprises nitrogen gas (N₂), ammonia, hydrazine, hydrogen gas (H₂), forming gas, or any combination thereof.

18. The method of claim 17, wherein the metal oxide comprises the metal contained in the barrier film.

19. The method of claim 18, wherein the metal oxide comprises titanium oxide, tantalum oxide, tungsten oxide, titanium oxynitride, tantalum oxynitride, tungsten oxynitride, alloys thereof, or any combination thereof.

20. The method of claim 17, wherein the temperature of the process chamber is about 100°

C. to about 350°

C. when the metal contact and the barrier film are exposed to the oxidizing agent.