STRUCTURED COATING SOURCE

Abstract

A coating source for physical vapor deposition has a coating material which consists of a brittle material and has cracks. The coating source additionally has a support element which is joined to the coating material at a surface of the coating material. Furthermore, the coating material has structuring on at least parts of a surface of the coating material. There is also described a process for producing a coating source.

Claims

1-20. (canceled)

21. A coating source for physical vapor deposition, the coating source comprising: a coating material being a brittle material and having cracks, said coating material having structuring on at least parts of a surface of said coating material; and a support element joined to said coating material at a surface of said coating material.

22. The coating source according to claim 21, wherein said cracks run primarily along said structuring.

23. The coating source, according to claim 21, wherein a proportion of more than 50% of a total crack length of said cracks runs along said structuring.

24. The coating source according to claim 21, wherein said structuring is formed on a surface of said coating material averted from said support element.

25. The coating source according to claim 21, wherein said structuring comprises an arrangement of a first group of parallel linear depressions and a second group of parallel linear depressions, and wherein said second group of parallel linear depressions is oriented to enclose an angle of between 70? and 110? with said first group of parallel linear depressions.

26. The coating source according to claim 21, wherein said coating material has a coefficient of thermal expansion ?.sub.2 that is greater than a coefficient of thermal expansion ?.sub.3 of said support element.

27. The coating source according to claim 21, wherein said coating material is a material selected from the group consisting of TiB.sub.2, SiC, B.sub.4C, MoSiB and CrSiB.

28. The coating source according to claim 21, wherein said support element consists of a material selected from the group consisting of molybdenum, tungsten, tantalum, a molybdenum-based alloy, a tungsten-based alloy and a tantalum-based alloy.

29. The coating source according to claim 21, wherein said support element has an E modulus E.sub.3 greater than or equal to 300 GPa.

30. The coating source according to claim 21, wherein said coating material has a thickness d.sub.2, said support element has a thickness d.sub.3, and wherein a ratio X=d.sub.2/(d.sub.2+d.sub.3) of the thickness d.sub.2 to a sum d.sub.2+d.sub.3 of the thickness d.sub.2 and the thickness d.sub.3 is greater than 0.5.

31. The coating source according to claim 30, wherein the ratio X=d.sub.2/(d.sub.2+d.sub.3) is greater than or equal to 0.6.

32. The coating source according to claim 21, formed as a plate-shaped coating source or a tubular coating source.

33. A process for producing a coating source for physical vapor deposition, the process comprising the following steps: providing a coating material being a brittle material; structuring the coating material to produce structuring on at least a portion of a surface of the coating material; providing a support element; joining of the coating material to the support element; and introducing cracks into the coating material.

34. The process according to claim 33, wherein the structuring step comprises effecting a process step selected from the group consisting of eroding, wire cutting, grinding or parting the coating material.

35. The process according to claim 33, wherein the structuring step comprises pressing the coating material with a profiled pressing tool.

36. The process according to claim 33, which comprises introducing the structuring on a surface of the coating material which, after joining to the support element, faces away from the support element.

37. The process according to claim 33, wherein the joining step comprises brazing at temperatures in a range from 400? C. to 950? C.

38. The process according to claim 33, wherein the step of introducing the cracks comprises cooling from an elevated temperature.

39. The process according to claim 38, wherein the joining step comprises brazing the coating material to the support element, and the step of introducing the cracks results from cooling the coating source from a brazing temperature.

40. The process according to claim 33, which further comprises a step of particle blasting the coating source.

Description

[0087] The figures show:

[0088] FIG. 1: Coating source (1) having a coating material (2), a support element (3) and structuring (5) before introduction of the cracks.

[0089] FIG. 2: Plan view of the coating source of FIG. 1.

[0090] FIG. 3: Plan view of a coating source (1) according to the invention after introduction of the cracks (4).

[0091] FIG. 4: Coating source having MoSiB coating material (Example 5) after brazing and cleaning with cracks formed.

[0092] FIG. 5: Coating source having TiB.sub.2 coating material (Example 6) brazed onto Mo back plate. Cracks made visible by dye penetration testing using fluorescent dye.

[0093] FIG. 6: Tubular coating source (1) having coating material (2), support or carrier tube (support element) (3) and structuring (5) after introduction of the cracks (4) in a) side view, in b) plan view.

[0094] FIG. 1 shows a coating source (1) for physical vapor deposition before introduction of the cracks. The coating source (1) has a coating material (2) and a support element (3). The coating material (2) is joined to the support element (3) at a surface of the coating material (2).

[0095] The coating material (2) has structuring (5). The structuring (5) consists of an arrangement of a first group of parallel linear depressions (shown as broken lines) and a second group of parallel linear depressions (shown as broken lines) which are arranged at right angles to the first group of parallel linear depressions.

[0096] FIG. 2 shows a plan view of the coating source of FIG. 1.

[0097] FIG. 3 shows a coating source according to the invention after introduction of the cracks (4). The cracks (4) run largely along the structuring (5).

[0098] FIG. 4 shows a coating source produced according to Example 5. It has an MoSiB coating material which was applied by means of brazing to a back plate made of Mo and subsequently cleaned. In addition to cracks along the structuring, there are also cracks which form an irregular network. No breaking-off of relatively small pieces of the coating material occurred.

[0099] FIG. 5 shows a coating source produced according to Example 6. It has a TiB.sub.2 coating material which was applied by means of brazing to a Mo back plate. The cracks introduced were made visible by means of fluorescent dye in a dye penetration test.

[0100] FIG. 6 shows a tubular coating source (1). A side view of the tubular coating source (1) is shown in a), and a plan view in the direction of the rotational axis of the coating source (1) is shown in b). The coating material (2) is in this case made up of individual cylindrical rings, and the support element (3) is configured as support or carrier tube. The structuring (5) is formed on the lateral surface of the coating material (2), and the cracks (4) run largely along the structuring (5).

LIST OF THE REFERENCE SYMBOLS USED

[0101] 1 coating source [0102] 2 coating material [0103] 3 support element [0104] 4 cracks [0105] 5 structuring [0106] d.sub.1 total thickness of the coating source [0107] d.sub.2 thickness of the coating material [0108] d.sub.3 thickness of the support element