Deposition of metal borides

Patent metadata

Field	Value
Publication number	US-10087522-B2
Application number	US-201615135224-A
Country	US
Kind code	B2
Filing date	Apr 21, 2016
Priority date	Apr 21, 2016
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A method for depositing a metal boride film onto a substrate is disclosed. In particular, the method comprises pulsing a metal halide precursor onto the substrate and pulsing a boron compound precursor onto the substrate. A reaction between the metal halide precursor and the boron compound precursor forms a metal boride film. Specifically, the method discloses forming a tantalum boride (TaB2) or a niobium boride (NbB2) film.

First claim

We claim:

1. A method of forming a metal boride comprising:
providing a substrate for processing in a reaction chamber;
performing a metal halide precursor deposition onto the substrate, the performing the metal halide precursor deposition step comprises:
pulsing a metal halide precursor comprising at least one of niobium tetrafluoride (NbF 4 ) and niobium pentafluoride (NbF 5 ) onto the substrate; and
purging an excess of the metal halide precursor from the reaction chamber; and

performing a borane compound precursor deposition onto the substrate, the performing the borane compound precursor deposition step comprises:
pulsing a borane compound precursor onto the substrate; and
purging an excess of the borane compound precursor from the reaction chamber;

wherein the metal halide precursor comprises a niobium halide;
wherein a reaction between the metal halide precursor and the borane compound precursor forms a niobium boride film;
wherein the metal halide precursor deposition step is repeated a predetermined number of times; and
wherein the borane compound precursor deposition step is repeated a predetermined number of times.

2. The method of claim 1 , wherein the borane compound precursor comprises at least one of: borane (BH 3 ), diborane (B 2 H 6 ), triborane (B 3 H 8 ), tetraborane (B 4 H 10 ), pentaborane, hexaborane, heptaborane, octaborane, nonaborane, decaborane, borane compounds that consist of only boron and hydrogen, amine boranes, cyclic borides, borazines, and borane compounds that do not include carbon, and other boron-containing precursors.

3. The method of claim 1 , wherein a temperature of the reaction chamber ranges between 200 and 400° C.

4. The method of claim 1 , wherein a pressure of the reaction chamber ranges between 0.5 and 8 Torr.

5. The method of claim 1 , wherein the pulsing the metal halide precursor has a duration between 0.1 and 10 seconds.

6. The method of claim 1 , wherein the pulsing the borane compound precursor has a duration between 0.1 and 10 seconds.

7. The method of claim 1 , wherein pulsing a borane compound precursor onto the substrate comprises adsorbing more than one monolayer of the borane compound onto the substrate.

8. The method of claim 1 , wherein one or more of purging the excess of the borane compound precursor and purging an excess of the metal halide precursor comprises flowing the borane compound precursor onto the substrate.

9. A method of forming a metal boride work function layer comprising:
providing a substrate for processing in a reaction chamber;
performing a metal halide precursor deposition onto the substrate, the performing the metal halide precursor deposition step comprises:
pulsing a metal halide precursor onto the substrate; and
purging an excess of the metal halide precursor from the reaction chamber; and

performing a borane compound precursor deposition onto the substrate, the performing the borane compound precursor deposition step comprises:
pulsing a borane compound precursor onto the substrate; and
purging an excess of the borane compound precursor from the reaction chamber;

wherein the metal halide precursor comprises one of: tantalum pentafluoride (TaF 5 ), niobium tetrafluoride (NbF 4 ), or niobium pentafluoride (NbF 5 ); and
wherein a reaction between the metal halide precursor and the borane compound precursor forms a metal boride comprising at least one of: tantalum boride (TaB 2 ) or niobium boride (NbB 2 ).

10. The method of claim 9 , wherein the borane compound precursor comprises at least one of: borane (BH 3 ), diborane (B 2 H 6 ), triborane (B 3 H 8 ), tetraborane (B 4 H 10 ), pentaborane, hexaborane, heptaborane, octaborane, nonaborane, decaborane, borane compounds that consist of only boron and hydrogen, amine boranes, cyclic borides, borazines, and borane compounds that do not include carbon, and other boron-containing precursors.

11. The method of claim 9 , wherein a temperature of the reaction chamber ranges between 200 and 400° C.

12. The method of claim 9 , wherein a pressure of the reaction chamber ranges between 0.5 and 8 Torr.

13. The method of claim 9 , wherein the pulsing the metal halide precursor has a duration ranging between 0.1 and 10 seconds.

14. The method of claim 9 , wherein the pulsing the borane compound precursor has a duration ranging between 0.1 and 10 seconds.

15. The method of claim 9 , wherein pulsing a borane compound precursor onto the substrate comprises adsorbing more than one monolayer of the borane compound onto the substrate.

16. The method of claim 9 , wherein one or more of purging the excess of the boron compound precursor and purging an excess of the metal halide precursor comprises flowing the borane compound precursor onto the substrate.

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

18. The method of claim 9 , wherein the metal boride has a concentration of niobium or tantalum from about 20 to about 70 at. %.

19. The method of claim 9 , wherein the metal boride has a concentration of Oxygen of less than 5 at. %.

20. The method of claim 9 , wherein the metal boride has a concentration of Hydrogen of less than 5 at. %.

21. The method of claim 9 , wherein the metal boride has a concentration of Fluorine of less than 5 at. %.

Assignees

• Asm Ip Holding Bv

Inventors

• Raisanen Petri
• Shero Eric
• Haukka Suvi
• Milligan Robert Brennan
• Givens Michael Eugene

Classifications

• C23C16/38 Primary

  Borides · CPC title

• C23C16/45525

  Atomic layer deposition [ALD] · CPC title

• C23C16/45523

  Pulsed gas flow or change of composition over time · CPC title

• C23C16/45553

  characterized by the use of precursors specially adapted for ALD · CPC title

• C23C16/45527

  characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations · CPC title