Apparatus and method for making sputtered films with reduced stress asymmetry

• US 20100175988A1
• Filed: 01/12/2009
• Published: 07/15/2010
• Est. Priority Date: 01/12/2009
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Stinson, R. Glenn, den Boer, Willem, Krasnov, Alexey
• Granted Patent: US 9,567,666 B2
• Time in Patent Office: Days
• US Class Current: 204/192.120
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: C23C 14/54 Controlling or regulating the coating process
• CPC Class Codes: H01J 37/3408 Planar magnetron sputtering
• CPC Class Codes: H01J 37/3447 Collimators, shutters, apertures

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%.

Claims

1. A magnetron 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 having a target material located thereon; and

at least one shield located proximate to the target such that a major axis of the each said shield runs parallel to a travel direction of the article to be sputter coated, each said shield being electrical isolated 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.

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

3. The sputtering apparatus of claim 1, further comprising a plurality of shields.

4. The sputtering apparatus of claim 3, 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.

5. The sputtering apparatus of claim 3, wherein each said shield is formed from stainless steel.

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

7. The sputtering apparatus of claim 3, wherein each said shield is negatively biased.

8. The sputtering apparatus of claim 3, wherein each said shield is spaced apart from the target.

9. The sputtering apparatus of claim 1, further comprising one or more magnets arranged to facilitate the sputter coating of the article.

10. The apparatus of claim 1, wherein a cathode is connected to the planar sputtering target.

11. 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%, more preferably less than about 5%.

12. A method of making a coated article, the method comprising:

sputtering a coating onto the article via a magnetron sputtering apparatus comprising a vacuum chamber, a sputtering target located in the vacuum chamber, the sputtering target having a target material located thereon, and at least one shield located proximate to the target such that a major axis of the shield runs parallel to a travel direction of the article to be sputter coated, each said shield being electrical isolated 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%.

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

14. The method of claim 12, wherein the sputtering apparatus further comprises a plurality of shields.

15. The method of claim 14, 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.

16. The method of claim 15, further comprising negatively biasing each said shield.

17. The method of claim 14, wherein each said shield is spaced apart from the target.

18. The method of claim 12, 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%.

19. The method of claim 12, 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%.

20. A magnetron 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 having a target material located thereon;

a cathode connected to the planar sputtering target;

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 a major axis of each said shield runs parallel to a travel direction of the article to be sputter coated, each said shield being electrical isolated and substantially non-magnetic,

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.

21. The apparatus of claim 20, 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%, more preferably less than about 5%.