Controllable target cooling

• US 20070023275A1
• Filed: 07/27/2005
• Published: 02/01/2007
• Est. Priority Date: 07/27/2005
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Inagawa, Makoto, Hosokawa, Akihiro, Tanase, Yoshiaki
• Granted Patent: US 8,182,661 B2
• Time in Patent Office: Days
• US Class Current: 204/192.100
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: H01J 37/3408 Planar magnetron sputtering
• CPC Class Codes: H01J 37/3497 Temperature of target
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A sputter target assembly particularly useful for a large panel plasma sputter reactor having a target assembly sealed both to the main processing chamber and a vacuum pumped chamber housing a moving magnetron. The target assembly to which target tiles are bonded includes an integral plate with parallel cooling holes drilled parallel to the principal faces. The ends of the holes may be sealed and vertically extending slots arranged in two staggered groups on each side and machined down to respective pairs of cooling holes on opposite sides of the backing plate in pairs. Four manifolds tubes are sealed to the four groups of slots and provide counter-flowing coolant paths.

Claims

1. A sputtering target, comprising:

a backing plate including a plurality of laterally extending parallel cylindrical cooling holes formed therein; and

one or more sputtering target tiles bonded to one of two principal surfaces of the backing plate.

2. The target of claim 1, wherein the cooling holes extend parallel to the one principal surface.

3. The target of claim 1, wherein the backing plate is an integral plate.

4. The target of claim 1, wherein the cooling holes have a diameter at least 25% of a thickness of the backing platc.

5. The target of claim 1, wherein the cooling holes are adapted to be coupled to at least one liquid cooling supply line and to at least one liquid cooling drain line.

6. The target of claim 1, wherein the cooling holes are seated at lateral ends thereof and wherein the backing plate further includes inlet and outlet holes extending from at least one of the principal surfaces of the backing plate to the cooling holes.

7. The target of claim 6, wherein the inlet and outlet holes are coupled to respective pluralities of the cooling holes in alternating groups thereof.

8. The target of claim 7, wherein the pluralities are between 2 and 6.

9. The target of claim 7, wherein the inlet and outlet holes are elongate holes.

10. The target of claim 7, further comprising four liquid manifolds coupled to respective ones of two of the groups on opposed lateral sides of the backing plate.

11. The target of claim 10, further comprising two manifold plates to which arc fixed respective pairs of the liquid manifolds and which are detachably affixable to the backing plate.

12. The target of claim 11, further comprising O-rings sealing the manifold plates to the backing plate.

13. The target of claim 10, wherein liquid coolant is supplied to and drained from the four liquid manifolds to provide counter coolant flows in parallel ones of the holes.

14. The target of claim 10, further comprising at least one hose fitting affixed to each of the liquid manifolds.

15. The target of claim 1, wherein the backing plate has a substantially rectangular shape.

16. The target of claim 1, wherein the one or more target tiles are bonded to the backing plate in substantially rectangular area.

17. A target backing plate, comprising:

an integral metal plate; and

a plurality of parallel cooling holes extending through the plate parallel to a principal surface of the metal plate having a target area which is configured to be bonded to one or more target tiles.

18. The target backing plate of claim 17, wherein said holes are cylindrical.

19. The target backing plate of claim 17, further comprising:

two sets of two staggered rows of access holes formed in the principal surface and disposed on each of lateral ends of the metal plate, wherein the two staggered rows of access holes of each set expose different ones of the cooling holes; and

wherein said target area is disposed between two lateral ends including the two staggered rows.

20. The target backing plate of claim 19, wherein each of the access holes exposes at least two of the cooling holes.

21. A method of sputtering in a sputter reactor having a target assembly with parallel cooling channels formed laterally therethrough and sealed on one side to a processing chamber containing a substrate to be sputter coated and on a second side to a magnetron chamber containing a scanned magnetron, comprising flowing a liquid coolant in opposed directions in different ones of the cooling channels.

22. The method of claim 21, wherein the cooling channels are cylindrical holes bored through a plate on which one or more target tiles are bonded.

23. A sputtering method performed in a sputter reactor comprising a main chamber containing a substrate to be processed, a target backing plate to which is bonded one or more target tiles and which is sealed to the main chamber, and a vacuum-pumped magnetron chamber sealed to the backing plate, said method comprising the flowing coolant in counter-flowing directions through respective pluralities of cylindrical cooling holes formed in and extending across the backing plate in parallel to a principal surface of the backing plate.