Magnetron sputtering apparatus and process

• US 4,851,095 A
• Filed: 02/08/1988
• Issued: 07/25/1989
• Est. Priority Date: 02/08/1988
• Status: Expired due to Term

• Current Assignee: JDS Uniphase Corporation (Lumentum Holdings Inc.)
• Original Assignee: Optical Coating Laboratory, Inc. (Lumentum Holdings Inc.)
• Inventors: Austin, R. Russel, Seddon, Richard I., Scobey, Michael A., Seeser, James W., Manley, Barry W., LeFebvre, Paul M.
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US07/154,177
• Time in Patent Office: 533 Days
• Field of Search: 204/192.10, 204/192.12, 204/192.15, 204/192.26-192.29, 204/298, 204/298 PM, 204/298 MD, 204/298 MB, 204/298 MC, 204/298 SM, 118/719
• US Class Current: 204/192.12
• CPC Class Codes: C23C 14/0047 Activation or excitation of reactive gases outside the coating chamber
• CPC Class Codes: C23C 14/0078 by moving the substrates between spatially separate sputtering and reaction stations
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/10 Glass or silica
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: C23C 14/352 using more than one target C23C14/56 takes precedence
• CPC Class Codes: C23C 14/505 for rotation of the substrates
• CPC Class Codes: C23C 14/56 Apparatus specially adapted for continuous coating; Arrangements for maintaining the vacuum, e.g. vacuum locks
• CPC Class Codes: C23C 14/562 for coating elongated substrates
• CPC Class Codes: C23C 14/58 After-treatment
• CPC Class Codes: C23C 8/02 Pretreatment of the material to be coated C23C8/04 takes precedence
• CPC Class Codes: H01J 2237/022 Avoiding or removing foreign or contaminating particles, debris or deposits on sample or tube

Abstract

A rotary cylindrical sputtering system incorporates separate, separately-controlled linear magnetron sputter cathode and reaction zones for sputter depositing materials such as refractory metals and forming oxides and other compounds and alloys of such materials. The associated process involves rotating or translating workpieces past the differentially pumped, atmospherically separated, sequentially or simultaneously operated cathode and reaction zones and is characterized by the ability to form a wide range of materials, by high throughput, and by controlled coating thickness, including both constant and selectively varied thickness profiles.

Claims

1. A sputter coating system, comprising:

a vacuum chamber;

a rotatable drum mounted within said chamber adapted for mounting substrates thereon for rotating the substrates;

at least one linear magnetron sputter device positioned at a work station adjacent the circumference of said drum and adapted for sputtering at least a selected material onto said substrate; and

at least a second device positioned adjacent the circumference of said drum and adapted for providing a plasma for effecting chemical reaction with said selected material.

2. The system of claim 1, wherein the second device is adapted for providing a reactive atmosphere selected to at least partially convert said selected material to at least one of an oxide, a nitride, a hydride or a carbon-containing alloy or compound.

3. The system of claim 2, wherein the second device is adapted for oxidizing said selected material.

4. The sputter coating system of claim 1, wherein the magnetron sputter device and the second device are positioned outside the drum.

5. The sputter coating system of claim 1, wherein the magnetron sputter device and the second device are positioned inside the drum.

6. The sputter coating system of claim 1, further comprising substrate support means rotatably mounted at the circumference of said drum for rotatably presenting selected substrates or surface segments thereof to the work station.

7. The sputter coating system of claim 6, wherein the rotatable mounting means comprises a planetary gear arrangement which is rotatable in conjunction with rotation of the drum.

8. The sputter coating system of claim 1, further comprising at least a second linear magnetron sputter device or group of linear magnetron sputter devices adapted for depositing at least a second material onto substrates at a second work station or group of work stations adjacent the circumference of said drum.

9. A magnetron sputtering system for sputter depositing at least one selected material on a substrate and effecting reaction of said material with a reactive plasma, comprising:

a vacuum chamber;

a rotatable drum mounted within said chamber and adapted for mounting substrates thereon for rotating the substrates past associated selected work stations;

said drum and said vacuum chamber defining therebetween a relatively narrow elongated reaction volume;

at least one linear magnetron sputter device positioned at a first work station location adjacent the circumference of said drum and comprising a target of selected material adapted for generating a first plasma throughout the reaction volume for sputter depositing the at least one selected material onto said substrates at a relatively low ambient partial pressure of said reactive gas; and

at least one ion source device positioned at a second work station location adjacent the circumference of said drum and adapted for applying a reactive gas in interaction with the plasma associated with the sputter device for generating a second plasma in said reaction volume to effect reaction of ions of said reactive gas with said sputter-deposited material.

10. The system of claim 9, wherein the ion source device is adapted for providing a reactive atmosphere selected to at least partially convert said selected material to at least one of an oxide, a nitride, a hydride or a carbon-containing alloy or compound.

11. The system of claim 10, wherein the ion source device is adapted for oxidizing said selected material.

12. The system of claim 9, wherein the ion source device is a linear magnetron device.

13. The system of claim 9, wherein the ion source device is an ion gun.

14. The system of claim 9, further incorporating and being adapted for operating at least two of said sputtering devices simultaneously for sputter depositing at least two materials simultaneously.

15. The magnetron sputtering system of claim 9, wherein the sputter device is positioned outside the drum.

16. The magnetron sputtering system of claim 9, wherein the sputter device is positioned inside the drum.

17. The magnetron sputtering system of claim 9, further comprising substrate support means rotatably mounted adjacent the circumference of the drum for rotatably presenting selected substrates or surface segments thereof to the work station.

18. The magnetron sputtering system of claim 17, wherein the rotatable mounting means comprises a planetary gear arrangement which is rotatable in conjunction with rotation of the drum.

19. A magnetron sputtering system, comprising:

a rotating drum;

unwind and wind roll means internal to said drum and adapted for traversing a flexible web through an opening in said drum and about the external circumference of said drum continuously or intermittently; and

at least a first linear magnetron sputterer or first group of linear magnetron sputterers selectively positioned about the periphery of said drum for depositing at least a first material on said web or substrates mounted thereon.

20. A magnetron sputtering system adapted for sputter depositing at least a first material on a web or substrates mounted thereon and for selectively oxidizing said material in reactive gas, comprising:

a rotating drum;

unwind and wind roll means internal to said drum and adapted for traversing a flexible web through an opening in and about the external circumference of said drum continuously or intermittently;

at least a first linear magnetron sputter device or first group of linear magnetron sputter devices positioned at selected work stations about the periphery of the circumference of said drum for selectively depositing at least a first material onto said drum or substrates mounted thereon, the cathode of said magnetron being surrounded by baffle means for substantially enclosing a sputter chamber region between said cathode and said associated workpiece station; and

at least a second ion source device or group of said second devices positioned at associated work stations and adapted for oxidizing said sputter deposited material at a relatively high partial pressure of said reactive gas.

21. The system of claim 20 incorporating and adapted for operating at least two of said linear magnetron sputtering devices simultaneously for sputter depositing at least two materials simultaneously.

22. A low temperature, high formation rate process for forming single layer films and multi-layer composites on substrates, comprising:

providing a vacuum chamber having a rotatable cylindrical workpiece mounting support formed therein and at least a first linear magnetron sputter device positioned adjacent the circumference of the drum for depositing a selected material onto the workpiece and at least a first oxidizer device positioned adjacent the periphery of the cylindrical support for oxidizing said sputter-deposited material;

pulling a vacuum in said chamber;

rotating said support; and

selectively and sequentially operating said devices to deposit a layer of said material on said substrate and oxidize said layer.

23. The magnetron sputtering process of claim 22, further comprising sequentially sputter depositing a stack of materials on said substrate and selectively operating the oxidizing devices to oxidize at least selected ones of said layers prior to sputter deposition of the next successsive layer.

24. A sputter coating system comprising:

a vacuum chamber;

a movable workpiece carrier mounted within said vacuum chamber and adapted for mounting substrates thereon for moving the substrates past at least first and second physically spaced work stations;

a linear magnetron-enhanced sputter device positioned at said first work station and including a target of selected material and means for generating an associated plasma within said device and adjacent said work station and substantially throughout an extended region of the chamber including the physically spaced second work station, for sputter depositing material on said substrates traversing the first work station; and

a linear magnetron-enhanced ion source positioned at said second work station and adapted for using electrons from said plasma associated with said sputter device and applying reactive gas to form along a relatively narrow zone adjacent the workpiece carrier a second plasma comprising ions of the reactive gas, the ion source further comprising means for applying a directed potential between said ion source and said plasma associated with said sputter device for accelerating the reactive ions to the substrates for effecting a selected reaction with the sputter-deposited material; and

means adapted for reciprocating the substrate carrier past the work stations a plurality of times to achieve the desired film coating thickness.

25. The sputter coating system of claim 24, wherein said workpiece carrier is cylindrical and rotatably moves the substrates past the first and second work stations and wherein said selected reaction occurs along a circumferential zone of the carrier comprising substantially less than one-half the circumference of the carrier.

26. The sputter coating system of claim 24, wherein said workpiece carrier is substantially flat and said movement is substantially linear.

27. The sputter coating system of claim 24, further comprising at least a second sputter device for sputter depositing the selected material.

28. The sputter coating system of claim 27, further comprising at least a plurality of said linear magnetron-enhanced ion sources for reacting selected reactive gas with the sputter deposited material.

29. The sputter coating system of claim 24, further comprising at least a second sputter device adapted for depositing at least a second material onto substrates.

30. The sputter coating system of claim 29, further comprising at least a plurality of said linear magnetron-enhanced ion sources for reacting selected reactive gas with the sputter deposited material.

31. The sputter coating system of claim 24, further comprising a multiplicity of sputter devices adapted for depositing at least first and second materials onto substrates.

32. The sputter coating system of claim 31, further comprising at least a multiplicity of said linear magnetron-enhanced ion sources for reacting selected reactive gas with the sputter deposited material.

33. The sputter coating system of claim 24, wherein the ion source is adapted for the inlet of a reactive atmosphere selected to at least partially convert said selected materials to at least one of an oxide, nitride, hydride or carbon-containing alloy or compound.

34. The system of claim 33, wherein the ion source is adapted for oxidizing said selected materials.

35. A process for forming single layer films and multi-layer composite films on substrates, comprising:

providing a vacuum chamber having a movable workpiece carrier thereon and at least one magnetron-enhanced sputter cathode device positioned adjacent the workpiece carrier for sputter depositing a selected material onto the workpiece;

providing at least one ion source device positioned adjacent the workpiece carrier for providing a selected reaction with the selected material;

pulling a vacuum in the chamber;

moving the carrier past the devices;

selectively operating the sputter cathode device to deposit a layer of the selected material on the substrate; and

selectively operating the ion source device in sequence with the sputter cathode device for substantially completing the selected reaction during a single pass of the carrier.

36. The process of claim 35, wherein the workpiece carrier is cylindrical and the movement is rotational and wherein the selected reaction occurs along a fractional circumferential surface zone of the carrier comprising a distance substantially less than one-half the circumference of the carrier and the selected reaction is substantially completed during translation of said workpiece through said fractional distance.

37. The process of claim 35, wherein the workpiece carrier is substantially flat and the movement is substantially linear.

38. The deposition process of claim 35, wherein the selected reaction converts the sputter-deposited material to at least one of an oxide, a nitride, a hydride, a sulfide or a carbon-containing alloy or compound.

39. The deposition process of claim 35, wherein the selected reaction is oxidation and at least partially converts the selected material to an oxide thereof.

40. The deposition process of claim 35, further comprising operating the sputter cathode device to sputter deposit layers of selected materials on the substrate and selectively and sequentially operating the ion source device to react at least selected ones of the layers prior to sputter deposition of the next successive layer.

41. The deposition process of claim 40, wherein the selected reaction converts the sputter-deposited material to at least one of an oxide, a nitride, a hydride, a sulfide or a carbon-containing alloy or compound.

42. The deposition process of claim 40, wherein the selected reaction converts at least selected ones of the layers to oxides of the selected materials.

43. The deposition process of claim 35, further comprising:

providing at least a plurality of sputter cathode devices.

44. The deposition process of claim 43, further comprising:

providing at least a plurality of the ion source devices.

45. The deposition process of claim 35, further comprising:

providing at least a plurality of the ion source devices.

46. The sputter deposition process of claim 35, further comprising selectively and sequentially operating the sputter cathode and the ion source devices to form a composite coating comprising at least a plurality of layers, the composition of each said layer being selected from at least one of a first metal, a second metal, an oxide of the first metal, an oxide of the second metal, mixtures of the first and second metals and an oxide of mixtures of the first and second metals.

47. The deposition process of claim 46, further comprising sequentially operating selected ones of the sputter cathode devices to sputter deposit layers of selected materials on said substrate and selectively and sequentially operating selected ones of the ion source devices in conjunction with supplying selected reactant gas thereto for effecting the selected reaction with at least selected ones of the layers prior to sputter deposition of the next successive layer.

48. The deposition process of claim 47, wherein the selected reaction involves converting the selected layers to at least one of oxide, nitride, hydride, sulfide or carbon-containing compound or mixture.

49. The deposition sputtering process of claim 47, wherein the selected reaction is oxidation.

50. A process for forming single layer films and multi-layer composite films on substrates, comprising:

providing a vacuum chamber having a rotatable cylindrical workpiece carrier therein and at least one magnetron-enhanced sputter cathode device positioned adjacent the circumference of the carrier for sputter depositing a selected material onto the workpiece;

providing at least one ion source device positioned adjacent the circumference of the workpiece carrier for providing a selected reaction with the workpiece during travel thereof along a fractional circumferential surface zone of the carrier comprising substantially less than one-half the circumference of the carrier;

pulling a vacuum in said chamber;

rotating the carrier;

selectively operating the sputter cathode device to deposit a layer of the selected material on said substrate; and

selectively operating the ion source device in sequence with said sputter cathode device for substantially completing the selected reaction during one pass of the workpiece along the surface zone.

51. A process for forming on concave substrates single layer films and multi-layer composite films of selected variable thickness profile in the direction from the center to the edge of the substrate, comprising providing a linear magnetron-enhanced sputter cathode device having an associated sputtering zone of relatively elongated height and relatively narrow width;

providing a rotatable cylindrical workpiece carrier adjacent the sputtering cathode device and supporting the substrate along the circumference thereof for traversing past the sputtering device;

providing a linear magnetron-enhanced ion source device having an associated reaction zone of relatively elongated height and relatively narrow width for providing a selected reaction with the deposited coating along a fractional circumferential zone of the carrier substantially less than one-half the circumference of the carrier;

rotating the cylindrical workpiece carrier;

selectively operating the sputtering cathode device to deposit at least a layer of selected material on the rotating substrate; and

selectively operating the ion source device to effect the selected reaction and complete the selected reaction during a single traversal of the workpiece through the fractional circumferential zone.