Deposition of metal borides

• US 10,190,213 B2
• Filed: 04/21/2016
• Issued: 01/29/2019
• Est. Priority Date: 04/21/2016
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Zhu, Chiyu, Shrestha, Kiran, Haukka, Suvi
• Primary Examiner(s): Chen, Bret P
• Application Number:
  US15/135,333
• Publication Number:
  US 20170306480A1
• Time in Patent Office: 1,013 Days
• CPC Class Codes: C23C 16/38 Borides
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD

Abstract

A method for depositing a metal film onto a substrate is disclosed. In particular, the method comprises pulsing a metal halide precursor onto the substrate and pulsing a decaborane precursor onto the substrate. A reaction between the metal halide precursor and the decaborane precursor forms a metal film, specifically a metal boride.

Claims

1. A method of forming a film having a metal boride comprising:

providing a substrate for processing in a reaction chamber;

performing a metal precursor deposition onto the substrate, the performing the metal precursor deposition step comprises;

pulsing a metal precursor onto the substrate; and

purging an excess of the metal precursor from the reaction chamber; and

performing a decaborane precursor deposition onto the substrate, the performing the decaborane precursor deposition step comprises;

pulsing a decaborane precursor onto the substrate, wherein prior to entering into the reaction chamber, the decaborane precursor is kept at a temperature not exceeding 65°

C.; and

purging an excess of the decaborane precursor from the reaction chamber;

wherein the metal precursor comprises one of;

titanium tetrachloride (TiCl₄), niobium pentachloride (NbCl₅), tantalum pentafluoride (TaF₅), and niobium pentafluoride (NbF₅) and wherein prior to entering the reaction chamber, the metal halide is kept at temperature ranging between 50°

C. and 120°

C.;

wherein a reaction between the metal halide precursor and the decaborane precursor forms a film comprising at least one of;

titanium boride (TiB), tantalum boride (TaB), or niobium boride (NbB);

wherein the metal precursor deposition step is repeated a predetermined number of times; and

wherein the decaborane precursor deposition step is repeated a predetermined number of times.

2. The method of claim 1, wherein a temperature of the reaction chamber is greater than 300°

C.

3. The method of claim 2, wherein the temperature of the reaction chamber is greater than 375°

C.

4. The method of claim 1, wherein a pressure of the reaction chamber ranges between 0.1 and 10 Torr.

5. The method of claim 1, wherein the pulsing the metal precursor has a duration of 0.1 and 5 seconds.

6. The method of claim 1, wherein the pulsing the decaborane precursor has a duration of 0.05 and 20 seconds.

7. The method of claim 1, wherein purging the excess of the metal precursor comprises purging the reaction chamber with at least one of:

nitrogen (N₂), argon (Ar), helium (He), hydrogen (H₂), or other rare gases.

8. The method of claim 1, wherein purging the excess of the decaborane precursor comprises purging the reaction chamber with at least one of:

nitrogen (N₂), argon (Ar), helium (He), hydrogen (H₂), or other rare gases.

9. The method of claim 1, wherein the film has a concentration of Boron from about 30 to about 80 at. %.

10. The method of claim 1, wherein the film has a concentration of a metal from about 20 to about 70 at. %.

11. The method of claim 1, wherein the film has a concentration of Oxygen of less than 5 at. %.

12. The method of claim 1, wherein the film has a concentration of Hydrogen of less than 5 at. %.

13. The method of claim 1, wherein the film has a concentration of a halide of less than 5 at. %.

14. A method of forming a film having a metal boride comprising:

providing a substrate for processing in a reaction chamber;

exposing the substrate to a metal halide precursor, wherein prior to entering the reaction chamber, the metal halide is kept at temperature ranging between 50°

C. and 120°

C.;

exposing the substrate with a purge gas after exposing the substrate to the metal halide precursor;

exposing the substrate to a decaborane precursor, wherein prior to entering into the reaction chamber, the decaborane precursor is kept at a temperature not exceeding 65°

C.; and

exposing the substrate with the purge gas after exposing the substrate to the decaborane precursor;

wherein the metal halide precursor exposing step is repeated a predetermined number of times; and

wherein the decaborane precursor exposing step is repeated a predetermined number of times.

15. The method of claim 14, wherein the purge gas comprises at least one of:

nitrogen (N₂), argon (Ar), helium (He), hydrogen (H₂), or other rare gases.

16. The method of claim 14, wherein a temperature of the reaction chamber is greater than 300°

C.

17. The method of claim 16, wherein the temperature of the reaction chamber is greater than 375°

C.

18. The method of claim 14, wherein exposing the substrate to the metal halide precursor comprises pulsing the metal halide precursor.

19. The method of claim 14, wherein exposing the substrate to the decaborane precursor comprises pulsing the decaborane precursor.

20. The method of claim 14, wherein exposing the substrate to the purge gas comprises pulsing the purge gas.