Enhanced collimated sputtering apparatus and its method of use

• US 6,036,821 A
• Filed: 01/29/1998
• Issued: 03/14/2000
• Est. Priority Date: 01/29/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Warren, Ronald A.
• Primary Examiner(s): DIAMOND, ALAN D
• Application Number:
  US09/015,703
• Time in Patent Office: 775 Days
• Field of Search: 204/192.12, 204/192.13, 204/192.3, 204/192.32, 204/192.33, 204/298.03, 204/298.09, 204/298.11, 204/298.15, 204/298.25-298.28 , 204/298.31, 204/298.32, 204/298.35, 204/192.25, 204/298.29
• US Class Current: 204/192.12
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: C23C 14/564 Means for minimising impurities in the coating chamber such as dust, moisture, residual gases
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: H01J 37/34 operating with cathodic sputtering H01J37/36 takes precedence ; methods of cathodic sputtering C23C14/34
• CPC Class Codes: H01J 37/3447 Collimators, shutters, apertures

Abstract

A sputtering apparatus using a collimator disposed between a wafer holder for holding a wafer and a target to intercept some of the particles ejected from the target, wherein the collimator is movable in a direction parallel to the wafer surface in a manner permitting the collimator to be cleaned and maintained in situ simultaneous with sputtering deposition processing.

Claims

1. A sputtering apparatus for sputtering a thin film on a substrate, the substrate having a surface, the apparatus comprising:

a target and a sputter processing region between the substrate and said target;

a collimator having a first portion and a second portion connected to said first portion, said first portion located in said sputter processing region, said second portion located outside said sputter processing region, wherein said collimator includes passageways oriented substantially perpendicular to said substrate surface; and

drive means to induce lateral displacement of said collimator in a direction parallel to the substrate surface, the drive means being sufficient to move said entire first portion of said collimator out of said sputter processing region and to move said second portion into said sputter processing region.

2. The sputtering apparatus of claim 1, wherein said collimator passageways traverse maintenance and/or monitoring stations outside said sputter processing region before being moved to the sputtering processing region by said drive means.

3. The sputtering apparatus of claim 1, wherein said drive means inducing said lateral displacement of said collimator is a rotary drive means.

4. The sputtering apparatus of claim 1, wherein said drive means inducing said lateral displacement of said collimator is a reciprocal drive means.

5. The sputtering apparatus of claim 1, further comprising a collimator passageway aperture-size measurement means positioned outside said sputter processing region.

6. The sputtering apparatus of claim 5, wherein said passageway aperture-size measurement means includes electro-optical sensing means.

7. The sputtering apparatus of claim 1, further comprising a collimator temperature measurement means positioned outside said sputter processing region.

8. The sputtering apparatus of claim 7, wherein said collimator temperature measurement means is a pyrometer.

9. The sputtering apparatus of claim 1, further comprising a collimator cooling means positioned outside said sputter processing region.

10. The sputtering apparatus of claim 1, further comprising a collimator passageway cleansing means positioned outside said sputter processing region.

11. The sputtering apparatus of claim 10, wherein said collimator passageway cleaning means comprises equipment capable of creating an etching plasma in the vicinity of said collimator.

12. The sputtering apparatus of claim 11, wherein said collimator passageway cleaning means comprises equipment capable of creating sputtering ions which bombard said collimator.

13. The sputtering apparatus of claim 1, wherein said collimator includes a matrix of walls defining said passageways, and said matrix walls contain active cooling lines carrying a flowing cooling medium dissipating heat from said collimator.

14. The sputtering apparatus of claim 13, further comprising process control means capable of interrupting processing to alert an operator to replace said collimator or adjusting a process parameter selected from the group consisting of sputter deposition time, sputter power input, collimator lateral displacement speed, cooling medium flow rate, temperature in cooling lines, and collimator re-positioning to compensate for any uneven collimator plugging.

15. The sputtering apparatus of claim 1, further comprising means to induce localized lateral displacements of said collimator passageways in said direction parallel to said substrate surface.

16. A sputtering apparatus for sputtering a thin film on a substrate, the substrate having a substrate surface, the apparatus comprising:

a target and a sputter processing region between the substrate and said target;

a circular collimator having a first portion and a second portion, said first portion located in said sputter processing region, said second portion located outside said sputter processing region, wherein said collimator includes passageways oriented substantially perpendicular to said substrate surface; and

rotary drive means to induce rotation of said collimator, said rotary drive means being sufficient to move said entire first portion of said collimator out of said sputter processing region and to move said second portion into said sputter processing region.

17. The sputtering apparatus of claim 16, wherein said collimator has a diameter at least twice as large as the diameter of said target, and said collimator has a central axis of rotation located laterally beyond an outermost side edge of said substrate.

18. A sputtering apparatus for sputtering a thin film on a substrate, the substrate having a substrate surface, the apparatus comprising:

a target and a sputter processing region between the substrate and said target;

a collimator of parallelogram geometry having a first portion and a second portion, said first portion located in said sputter processing region, said second portion located outside said sputter processing region, wherein said collimator includes passageways oriented substantially perpendicular to said substrate surface; and

a reciprocal drive means to induce back-and-forth movement of said collimator across said sputter processing region, said reciprocal drive means being sufficient to move said entire first portion of said collimator out of said sputter processing region and to move said second portion into said sputter processing region.

19. The sputtering apparatus of claim 18, further comprising a pair of maintenance and/or monitoring stations located on opposite lateral sides of said sputter processing region along a line of reciprocal movement of the collimator.

20. A method of sputtering thin film on a substrate, the substrate having a surface, the method comprising the steps of:

providing a sputtering apparatus having a target and a sputter processing region between the substrate and said target, and a collimator having a first portion and a second portion connected to said first portion, said first portion located in said sputter processing region, said second portion located outside said sputter processing region, said collimator including passageways oriented substantially perpendicular to said substrate surface;

generating a plasma gas in said sputter processing region and bombarding said target with accelerated ions from the plasma gas to eject film-forming particles from said target; and

laterally displacing said collimator in a direction parallel to said surface of said substrate, the lateral displacing step moving said entire first portion of said collimator out of said sputter processing region and moving said second portion into said sputter processing region.

21. The method of claim 20, wherein said step of laterally displacing is achieved with a drive means selected from the group consisting of a rotary drive means and a reciprocating drive means.

22. The method of claim 20 further comprising the step of inspecting and/or performing maintenance on said collimator at a collimator inspection and/or maintenance station positioned outside said sputter processing region, said collimator inspection and/or maintenance station being selected from a collimator passageway aperture-size measurement means, a collimator temperature measurement means, a collimator cooling means, and a collimator passageway cleaning means, and combinations thereof.

23. The method of claim 20, further comprising the step of measuring a collimator passageway aperture-size outside said sputter processing region.

24. The method of claim 20, further comprising the step of measuring a collimator temperature outside said sputter processing region.

25. The method of claim 20, further comprising the step of cooling said collimator outside said sputter processing region.

26. The method of claim 20, further comprising the step of cleaning said collimator with an etching plasma or a region of etchant gas in the vicinity of said collimator outside said sputter processing region.

27. The method of claim 20, further comprising the step of cleaning said collimator by sputtering ions which bombard said collimator outside said sputter processing region.

28. The method of claim 20, wherein said collimator includes a matrix of walls defining said passageways, and said matrix of walls contain active cooling lines carrying a flowing cooling medium for dissipating heat from said collimator, and further comprising the step of cooling said collimator with said flowing cooling medium.

29. The method of claim 20 further comprising the step of controlling processing in said sputtering apparatus with a process control means which can control the process to perform a function selected from the group consisting of interrupting processing to alert an operator to replace said collimator, adjusting sputter deposition time, adjusting sputter power input, adjusting collimator lateral displacement speed, re-positioning said collimator to compensate for any uneven collimator plugging, adjusting cooling medium flow rate, and adjusting temperature in cooling lines.