Apparatus and method for making sputtered films with reduced stress asymmetry

Patent metadata

Field	Value
Publication number	US-9567666-B2
Application number	US-31891909-A
Country	US
Kind code	B2
Filing date	Jan 12, 2009
Priority date	Jan 12, 2009
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

Certain example embodiments of this invention relate to techniques for reducing stress asymmetry in sputtered polycrystalline films. In certain example embodiments, sputtering apparatuses that include one or more substantially vertical, non-conductive shield(s) are provided, with such shield(s) helping to reduce the oblique component of sputter material flux, thereby promoting the growth of more symmetrical crystallites. In certain example embodiments, the difference between the travel direction tensile stress and the cross-coater tensile stress of the sputtered film preferably is less than about 15%, more preferably less than about 10%, and still more preferably less than about 5%.

First claim

What is claimed is:

1. A sputtering apparatus for sputter coating an article in a reactive environment, comprising:
a vacuum chamber;
a sputtering target located in the vacuum chamber, the sputtering target including a target material and to be located over the article to be sputter coated; and
a plurality of substantially parallel shields located proximate to the target such that major axes of the respective shields are substantially parallel to each other and extend parallel to a travel direction of the article to be sputter coated in the sputtering apparatus, so that substantially parallel shields are only oriented parallel to the travel direction in the vacuum chamber and there are no shields in the vacuum chamber that are oriented in any other direction;
each said shield being electrically isolated and substantially non-magnetic, and wherein each said shield extends from the target perpendicularly toward a horizontal surface of the article to be sputter coated which is located below the target and below the shields and which is travelling in the travel direction in the sputtering apparatus, and wherein each said shield has a vertical depth that is substantially less than a distance between the target and the horizontal surface and each said shield does not extend below the horizontal surface of the article to be sputter coated; and
wherein each said shield is disposed in the vacuum chamber at a location suitable for reducing the oblique component of sputter material flux produced during the sputter coating of the article compared to an apparatus that lacked the shields such that a difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 15%.

2. The sputtering apparatus of claim 1 , wherein the sputtering target is substantially planar.

3. The sputtering apparatus of claim 1 , wherein the length of each said shield is substantially the same as the dimension of the target that corresponds to the travel direction of the article to be sputter coated.

4. The sputtering apparatus of claim 1 , wherein each said shield is formed from stainless steel.

5. The sputtering apparatus of claim 4 , wherein each said shield is formed from 300 series stainless steel.

6. The sputtering apparatus of claim 1 , wherein each said shield is negatively biased.

7. The sputtering apparatus of claim 1 , wherein each said shield is spaced apart from the target.

8. The sputtering apparatus of claim 1 , wherein said plurality of shields are provided in a grid that includes the plurality of shields.

9. The apparatus of claim 1 , wherein the target includes a cathode.

10. The apparatus of claim 1 , wherein each said shield is disposed in the vacuum chamber at a location suitable for reducing the oblique component of sputter material flux produced during the sputter coating of the article such that the difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 10%.

11. A method of making a coated article, the method comprising:
sputtering a coating onto an article to be sputter coated in a vacuum chamber, a sputtering target being located in the vacuum chamber, the sputtering target comprising a target material,
providing a plurality of substantially parallel shields proximate to the target such that major axes of the respective shields are substantially parallel to each other and extend parallel to a travel direction of the article to be sputter coated in the sputtering apparatus, and during said sputtering causing the article to be sputter coated to pass below the target and below the shields while travelling in the travel direction, and wherein substantially parallel shields are only oriented parallel to the travel direction in the vacuum chamber and there are no shields in the vacuum chamber that are oriented in any other direction; wherein
each said shield has a vertical depth that is substantially less than a distance between the target and a horizontal surface of the article to be sputter coated and each said shield does not extend below said horizontal surface of the article to be sputter coated;
each said shield being electrically isolated from the sputtering target and substantially non-magnetic,
wherein each said shield is disposed in the vacuum chamber at a location suitable for reducing the oblique component of sputter material flux produced during the sputter coating of the article such that the difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 15%.

12. The method of claim 11 , wherein the sputtering target is substantially planar.

13. The method of claim 11 , wherein the length of each said shield is substantially the same as the dimension of the target that corresponds to the travel direction of the article to be sputter coated.

14. The method of claim 13 , further comprising negatively biasing each said shield.

15. The method of claim 11 , wherein each said shield is spaced apart from the target.

16. The method of claim 11 , wherein the difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 10%.

17. The method of claim 11 , wherein the difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 5%.

18. A sputtering apparatus for sputter coating an article, comprising:
a vacuum chamber;
a sputtering target located in the vacuum chamber, the sputtering target comprising a target material and a cathode;
one or more magnets arranged to facilitate the sputter coating of the article; and
a plurality of shields located proximate to, and spaced apart from, the target such that the plurality of shields extend substantially parallel to each other and major axes of said respective shields run substantially parallel to a travel direction of the article to be sputter coated, each said shield being substantially non-magnetic, and the shields being interposed between the target and the article to be sputter coated, wherein substantially parallel shields are only oriented parallel to the travel direction in the vacuum chamber and there are no shields in the vacuum chamber that are oriented in any other direction;
wherein each said shield has a vertical depth that is substantially less than a distance between the target and a horizontal surface of the article to be sputter coated and each said shield does not extend below said horizontal surface of the article to be sputter coated;
wherein the length of each said shield is substantially the same as the dimension of the target that corresponds to the travel direction of the article to be sputter coated, and
wherein each said shield is disposed in the vacuum chamber at a location suitable for reducing the oblique component of sputter material flux produced during the sputter coating of the article compared to an apparatus that lacked the plurality of shields.

19. The apparatus of claim 18 , wherein each said shield is disposed in the vacuum chamber at a location suitable for reducing the oblique component of sputter material flux produced during the sputter coating of the article such that the difference between the travel direction tensile stress and the cross-coater tensile stress of the coating on the article is less than about 5%.

Assignees

• Krasnov Alexey
• Den Boer Willem
• Stinson R Glenn
• Guardian Industries

Inventors

• Krasnov Alexey
• Den Boer Willem
• Stinson R Glenn

Classifications

• C23C14/3407 Primary

  Cathode assembly for sputtering apparatus, e.g. Target · CPC title

• C23C14/54

  Controlling or regulating the coating process · CPC title

• H01J37/3447

  Collimators, shutters, apertures · CPC title

• H01J37/3408

  Planar magnetron sputtering · CPC title