Multilayer circuit devices and manufacturing methods using electroplated sacrificial structures

• US 8,003,513 B2
• Filed: 03/22/2005
• Issued: 08/23/2011
• Est. Priority Date: 09/27/2002
• Status: Expired due to Fees

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Pendo, Shaun, Shah, Rajiv
• Primary Examiner(s): Im; Junghwa M
• Application Number:
  US11/086,936
• Publication Number:
  US 20050161826A1
• Time in Patent Office: 2,345 Days
• Field of Search: 257/758, 438/622, 438/624, 438/618, 438/637, 438/623
• US Class Current: 438/622
• CPC Class Codes: H01L 21/4857 Multilayer substrates multilayer metallisation on monolayer substrate H01L21/4846
• CPC Class Codes: H01L 21/4867 Applying pastes or inks, e.g. screen printing H01L21/486 takes precedence
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H05K 1/162 incorporating printed capacitors
• CPC Class Codes: H05K 2201/0179 Thin film deposited insulating layer, e.g. inorganic layer for printed capacitor
• CPC Class Codes: H05K 2203/0278 Flat pressure, e.g. for connecting terminals with anisotropic conductive adhesive
• CPC Class Codes: H05K 2203/085 Using vacuum or low pressure
• CPC Class Codes: H05K 2203/1476 Same or similar kind of process performed in phases, e.g. coarse patterning followed by fine patterning
• CPC Class Codes: H05K 2203/308 Sacrificial means, e.g. for temporarily filling a space for making a via or a cavity or for making rigid-flexible PCBs
• CPC Class Codes: H05K 3/048 using a lift-off resist pattern or a release layer pattern
• CPC Class Codes: H05K 3/06 the conductive material being removed chemically or electrolytically, e.g. by photo-etch process semi-additive methods H05K3/108
• CPC Class Codes: H05K 3/4053 by thick-film techniques
• CPC Class Codes: H05K 3/4061 for via connections in inorganic insulating substrates
• CPC Class Codes: H05K 3/4664 Adding a circuit layer by thick film methods, e.g. printing techniques or by other techniques for making conductive patterns by using pastes, inks or powders H05K3/4647 takes precedence
• CPC Class Codes: H05K 3/467 Adding a circuit layer by thin film methods H05K3/4647 takes precedence

Abstract

A multilayer circuit includes a dielectric base substrate, conductors formed on the base substrate and a vacuum deposited dielectric thin film formed over the conductors and the base substrate. The vacuum deposited dielectric thin film is patterned using sacrificial structures formed by electroplating techniques. Substrates formed in this manner enable significant increases in circuit pattern miniaturization, circuit pattern reliability, interconnect density and significant reduction of over-all substrate thickness.

Claims

1. A method for forming a multilayer circuit device, comprising:

providing a base substrate;

forming at least one conductor on the base substrate;

electroplating at least one sacrificial structure on at least a portion of at least one of the base substrate and conductors to define areas to be protected from deposition of a predetermined material;

depositing a thin film of the predetermined material having a predetermined electrical or structural characteristic on at least a portion of the at least one electroplated sacrificial structure and at least a portion of at least one of the base substrate, and the at least one conductor; and

removing the electroplated sacrificial structures and, after removal of the electroplated sacrificial structures, removing the predetermined material deposited on the electroplated sacrificial structures, to leave a patterned deposited thin film of the predetermined material on at least one of the conductors and the base substrate.

2. The method claimed in claim 1, wherein depositing a thin film of a predetermined material comprises depositing a thin film of a dielectric material.

3. The method claimed in claim 1, wherein depositing a thin film of a predetermined material comprises depositing a thin film of an alumina material.

4. The method claimed in claim 1, wherein electroplating at least one sacrificial structure comprises forming a plurality of sacrificial structures by electroplating an electroplatable material onto at least a portion of at least one of the conductor and base substrate.

5. The method claimed in claim 1, wherein depositing a thin film of a predetermined material comprises vacuum depositing a thin film of the predetermined material.

6. The method claimed in claim 1, wherein depositing a thin film of a predetermined material comprises vacuum depositing a thin film of a dielectric material.

7. The method claimed in claim 1, wherein removing the electroplated sacrificial structures to leave a patterned deposited thin film of the predetermined material comprises applying an etchant to the sacrificial structures.

8. The method claimed in claim 7, wherein applying an etchant to the sacrificial structures comprises selecting and applying an etchant for a period of time, where the etchant is selected and the period of time is selected to cause removal of the electroplated sacrificial material and the predetermined material deposited on the electroplated sacrificial structure without removing so much of the predetermined material as to eliminate its predetermined electrical or structural characteristic.

9. The method claimed in claim 1, wherein electroplating at least one sacrificial structure comprises electroplating a gold material to form at least one electroplated gold sacrificial structure.

10. The method claimed in claim 9, wherein applying an etchant to the sacrificial structures comprises applying a ferric chlorice solution to the sacrificial structures.

11. The method claimed in claim 1, wherein electroplating at least one sacrificial structure comprises electroplating at least one sacrificial structure that has a thickness that is greater than the thickness of the thin film of predetermined material.

12. The method claimed in claim 1, wherein:

depositing a thin film of a predetermined material comprises depositing a thin film of alumina;

electroplating at least one sacrificial structure comprises electroplating a gold material to form at least one electroplated gold sacrificial structure; and

applying an etchant to the sacrificial structures comprises applying a ferric chlorice solution to the alumina thin film and gold sacrificial structures.

13. The method claimed in claim 1, wherein providing a base substrate comprises providing a flexible substrate formed of a flexible material.

14. The method claimed in claim 1, wherein the base substrate comprises a hermetic via, and wherein at least one of conductor is formed in contact the hermetic via.

27. The method claimed in claim 1, wherein removing the electroplated sacrificial structures and the predetermined material deposited on the electroplated sacrificial structures forms at least a portion of a pattern in the patterned deposited thin film of the predetermined material.

29. The method of claim 1, wherein the patterned deposited thin film of the predetermined material left, consists essentially of one or more portions of the dielectric material that were not deposited on the sacrificial structure.

15. A method for forming a multilayer circuit device, comprising:

providing a base substrate having at least one conductor supported thereon;

electroplating at least one sacrificial structure on at least one of the base substrate and the at least one conductor;

depositing a film of a dielectric material on at least a first portion of the at least one electroplated sacrificial structure and over at least a portion of at least one of the base substrate, and the at least one conductor; and

removing the electroplated sacrificial structures including the first portion of the at least one electroplated sacrificial structure and, after removal of the electroplated sacrificial structures, removing the dielectric material that had been deposited on the first portion of the at least one electroplated sacrificial structure, to leave a patterned deposited film of the dielectric material on at least a portion of at least one of the conductors and the base substrate.

16. The method claimed in claim 15, wherein depositing a film of a dielectric material comprises depositing a thin film of an alumina material.

17. The method claimed in claim 16, wherein electroplating at least one sacrificial structure comprises forming a plurality of sacrificial structures by electroplating an electroplatable material onto at least a portion of the at least one conductors and base substrate.

18. The method claimed in claim 16, wherein depositing a film of a dielectric material comprises vacuum depositing a thin film of the dielectric material.

19. The method claimed in claim 16, wherein removing the electroplated sacrificial structures to leave a patterned deposited thin film of the dielectric material comprises applying an etchant to the sacrificial structures.

20. The method claimed in claim 19, wherein applying an etchant to the sacrificial structures comprises selecting and applying an etchant for a period of time, where the etchant is selected and the period of time is selected to cause removal of the electroplated sacrificial material and the predetermined material deposited on the electroplated sacrificial structure without removing so much of the dielectric material as to eliminate its electrical or structural characteristic.

21. The method claimed in claim 16, wherein electroplating at least one sacrificial structure comprises electroplating a gold material to form at least one electroplated gold sacrificial structure.

22. The method claimed in claim 21, wherein applying an etchant to the sacrificial structures comprises applying a ferric chloride solution to the sacrificial structures.

23. The method claimed in claim 16, wherein electroplating at least one sacrificial structure comprises electroplating at least one sacrificial structure that has a thickness that is greater than the thickness of the film of dielectric material.

24. The method claimed in claim 16, wherein:

depositing a thin film of a dielectric material comprises depositing a thin film of alumina;

electroplating at least one sacrificial structure comprises electroplating a gold material to form at least one electroplated gold sacrificial structure; and

applying an etchant to the sacrificial structures comprises applying a ferric chloride solution to the alumina thin film and gold sacrificial structures.

25. The method claimed in claim 16, wherein providing a base substrate comprises providing a flexible substrate formed of a flexible material.

26. The method claimed in claim 16, wherein the base substrate comprises a hermetic via, and wherein at least one of conductor is formed in contact the hermetic via.

28. The method claimed in claim 15, wherein removing the electroplated sacrificial structures and the dielectric material deposited on the electroplated sacrificial structures forms at least a portion of a pattern in the patterned film of the dielectric material.

30. The method of claim 15, wherein the patterned deposited thin film of the predetermined material left, consists essentially of one or more portions of the dielectric material that were not deposited on the sacrificial structure.

32. The method claimed in claim 15, wherein depositing a film of a dielectric material on at least the first portion of the at least one electroplated sacrificial structure comprises depositing the film of dielectric material on top of an upward-facing surface of the first portion of the at least one electroplated sacrificial structure to at least partially support the film of dielectric material on the upward-facing surface of the first portion of the at least one electroplated sacrificial structure.

31. A method for forming a multilayer circuit device, the method comprising:

providing a base substrate having a surface generally extending along an x-y plane and at least one conductor supported on the surface;

electroplating at least one sacrificial structure on at least one of the base substrate surface and the at least one conductor; and

after producing a dielectric layer in a first pattern by depositing and at least partially supporting a film of a dielectric material on a surface of at least a portion of the at least one electroplated sacrificial structure and over at least a portion of at least one of the base substrate surface and the at least one conductor, producing a second pattern of the dielectric layer by removing both the at least one electroplated sacrificial structure and the portion of the dielectric material film of the first pattern deposited and supported on the surface of the at least one electroplated sacrificial structure,

wherein the second pattern of the dielectric layer is geometrically different from the first pattern of the dielectric layer with respect to at least one direction in the x-y plane.