High purity tungsten hexachloride and method for making same

Patent metadata

Field	Value
Publication number	US-10100406-B2
Application number	US-201615096872-A
Country	US
Kind code	B2
Filing date	Apr 12, 2016
Priority date	Apr 17, 2015
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

Condensable metal halide materials, such as but not limited to tungsten chloride (WCl 6 ), can be used to deposit metal films or metal containing films in a chemical vapor deposition (CVD) or atomic layer deposition process. Described herein are high purity compositions comprising condensable materials and methods to purify condensable materials. In one aspect, there is provided a composition comprising: tungsten hexachloride which is substantially free of at least one impurity and wherein the tungsten hexachloride comprises at least 90%, preferably 95% and more preferably 99% by weight or greater of a β-WCl 6 and 5% by weight or less of the α-WCl 6 as measured by X-ray diffraction.

First claim

The invention claimed is:

1. A composition for depositing a tungsten film or tungsten-containing film by a chemical vapor deposition or atomic layer deposition process, the composition comprising:
at least 99% by weight or greater of β-WCl 6 .

2. The composition of claim 1 , wherein the composition further comprises 1% by weight or less of WOCl 4 .

3. The composition of claim 1 , wherein the composition comprises 1% by weight or less of α-WCl 6 .

4. The composition of claim 3 , wherein the composition comprises at least 99.9% by weight or greater of β-WCl 6 .

5. A delivery system for depositing a tungsten film or tungsten-containing film comprising:
a composition comprising at least 90% by weight or greater of β-WCl 6 ;
a vessel; and
wherein the composition is inside the vessel and the vessel is maintained at a temperature ranging from 140° C. to 200° C.

6. The delivery system of claim 5 , wherein the composition comprises at least 95% by weight or greater of β-WCl 6 and 5% by weight or less of α-WCl 6 .

7. The delivery system of claim 5 , wherein the composition comprises at least 99.9% by weight or greater of β-WCl 6 and 1% by weight or less of α-WCl 6 .

8. The delivery system of claim 5 , wherein the composition comprises at least 99.9% by weight or greater of β-WCl 6 .

9. A process of preparing a delivery system for depositing a tungsten film or tungsten-containing film comprising:
providing a vessel;
providing a composition comprising at least 90% by weight of WCl 6 wherein the composition is inside the vessel; and
heating and maintaining the vessel to have at least 90.0% by weight of WCl 6 is β-WCl 6 .

10. The process of claim 9 , wherein the heating is performed until 95.0% by weight of WCl 6 is β-WCl 6 .

11. The process of claim 9 , wherein the heating is performed until 99.0% by weight of WCl 6 is β-WCl 6 .

12. The process of claim 9 , wherein the heating is performed until 99.9% by weight of WCl 6 is β-WCl 6 .

13. The process of claim 9 , wherein the vessel is heated and maintained at a temperature of 140° C. to 200° C.

14. A system for purifying a crude material comprising WCl 6 and at least one impurity comprising:
(a) at least one boiler;
(b) a condenser;
(c) a connector in fluid communication with the boiler and the condenser;
(d) a carrier gas in fluid communication with the boiler; and
(e) a fluidizing gas in fluid communication with the connector and the condenser;
wherein
the at least one impurity comprising at least one of trace metals, tungsten oxytetrachloride (WOCl 4 ), and tungsten pentachloride (WCl 5 );
the at least one boiler is maintained at a temperature above the boiling point of WCl 6 to convert filled crude material to gaseous phase mixing with the carrier gas to obtain boiler vapor stream;
the connector is filled with the boiler vapor stream;
the condenser containing the fluidizing gas mixing with the boiler vapor stream to obtain a condenser vapor containing purified material comprising WCl 6 at the bottom of the condenser while the fluidizing gas carrying the at least one impurity to the top of the condenser;
the carrier gas and the fluidizing gas are not react with WCl 6 ; and
the fluidizing gas is cooler than the boiler vapor stream.

15. The system of claim 14 , wherein the at least one boiler is maintained at >300° C.; and the condenser vapor is maintained at one or more temperatures ranging from about 100 to about 180° C.

16. The system of claim 14 ; wherein a molar ratio of the fluidizing gas and the boiler vapor stream is <200:1; and a molar ratio of the carrier gas to the crude material in the boiler vapor stream is <10:1.

17. The system of claim 14 ; wherein the condenser further comprises a dip tube in fluid communication with a vacuum pump to withdraw the purified material comprising WCl 6 from the bottom of the condenser.

18. The system of claim 14 ; wherein the purified material comprising WCl 6 comprises at least 90% by weight or greater of β-WCl 6 .

19. The system of claim 14 ; wherein the purified material comprising WCl 6 comprises at least 99% by weight or greater of β-WCl 6 .

20. The system of claim 14 ; wherein the system further comprises a vessel in fluid communication with the dip tube for housing the purified material comprising WCl 6 wherein the purified material comprising WCl 6 comprises at least 90% or 99% by weight or greater of β-WCl 6 .

Assignees

• Air Prod & Chem
• Versum Mat Us Llc

Inventors

• Wu Xiaoxi
• Ivanov Sergei Vladimirovich

Classifications

• C01P2006/80

  Compositional purity · CPC title

• C01G41/04 Primary

  Halides · CPC title

• C23C16/455 Primary

  characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber · CPC title

• B01D1/14

  with heated gases or vapours {or liquids} in contact with the liquid · CPC title

• B01D3/322

  Reboiler specifications · CPC title