Methods of producing a composite substrate

• US 7,487,587 B2
• Filed: 03/22/2006
• Issued: 02/10/2009
• Est. Priority Date: 03/22/2005
• Status: Active Grant

• Current Assignee: Interuniversitair Micro-Electronica Centrum VZW (IMEC International), Universiteit Gent Vzw
• Original Assignee: Interuniversitair Micro-Electronica Centrum VZW (IMEC International), Universiteit Gent Vzw
• Inventors: Axisa, Fabrice, Brosteaux, Dominique, Vanfleteren, Jan
• Primary Examiner(s): ARBES, CARL J
• Application Number:
  US11/387,446
• Publication Number:
  US 20060231288A1
• Time in Patent Office: 1,056 Days
• Field of Search: 298/25, 298/30, 298/46, 427/96.1
• US Class Current: 29/846
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 25/50 Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 2201/0133 Elastomeric or compliant polymer elastomeric conductor H05K2201/0314
• CPC Class Codes: H05K 2201/098 Special shape of the cross-section of conductors, e.g. very thick plated conductors
• CPC Class Codes: H05K 3/205 using a pattern electroplated or electroformed on a metallic carrier
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49158 with molding of insulated base

Abstract

Methods of producing a composite substrate and devices made by the methods are disclosed. One of the methods comprises providing a flexible sacrificial layer, producing one or more patterned conducting layers on the flexible sacrificial layer, bending the sacrificial layer into a predetermined shape, providing a stretchable and/or flexible material on top of and in between features of the one or more patterned layers.

Claims

1. A method of producing a composite substrate, comprising:

providing a flexible sacrificial layer;

producing one or more patterned conducting layers on the flexible sacrificial layer, the one or more patterned layers comprising a plurality of patterned features;

providing a stretchable and/or flexible material on top of and in between the patterned features; and

removing the sacrificial layer.

2. The method of producing a composite substrate according to claim 1, further comprising bending the sacrificial layer and the patterned features in a predetermined shape prior to providing the stretchable and/or flexible material.

3. The method of producing a composite substrate according to claim 1, wherein the patterned features comprise a shape such that the patterned features are anchored into the stretchable and/or flexible material.

4. The method of producing a composite substrate according to claim 1, wherein the patterned features comprise sloped sidewalls such that the patterned features are anchored into the stretchable and/or flexible material.

5. The method of producing a composite substrate according to claim 1 wherein the patterned features comprise a substantially trapezoidal shape.

6. The method of producing a composite substrate according to claim 1, further comprising:

removing part of the sacrificial layer underneath the patterned features so as to create gaps underneath the patterned features, after the producing of one or more patterned conducting layers; and

filling the gaps underneath the patterned features with the stretchable and/or flexible material such that the patterned features are anchored in the stretchable and/or flexible material.

7. The method of producing a composite substrate according to claim 1, wherein the patterned features are optically conducting or thermally conducting or electrically conducting.

8. The method of producing a composite substrate according to claim 1, wherein the patterned features comprise a metal or a semiconductor material.

9. The method of producing a composite substrate according to claim 1, wherein the sacrificial layer comprises a plurality of sub-layers.

10. The method of producing a composite substrate according to claim 9, wherein the at least one sacrificial sub-layer and the sacrificial layers are peeled off the patterned features and the stretchable and/or flexible material together.

11. The method of producing a composite substrate according to claim 9, wherein sacrificial sub-layers are etched off selectively with respect to the next sub-layer.

12. The method of producing a composite substrate according to claim 1, wherein the sacrificial layer is conducting.

13. The method of producing a composite substrate according to claim 12, wherein the producing comprises:

applying a resist layer;

patterning the resist layer;

electroplating one or more conducting layers; and

removing the resist layer.

14. The method of producing a composite substrate according to claim 1, wherein providing the stretchable and/or flexible material is achieved with one of the following techniques:

moulding, curtain coating, dispensing, dipping, and spincoating.

15. The method of producing a composite substrate according to claim 1, further comprising providing components into the composite substrate, the components being in electrical or optical contact with the patterned features.

16. The method of producing a composite substrate according to claim 15, wherein the patterned features form an interconnect section between the components.

17. The method of producing a composite substrate according to claim 15, further comprising applying an underfill material in substantially the whole area confined by the patterned features, the sacrificial layer and the components.

18. The method of producing a composite substrate according to claim 15, wherein the components are provided at the side where the sacrificial layer is removed.

19. The method of producing a composite substrate according to claim 18, further comprising providing a second layer of stretchable and/or flexible material surrounding the components.

20. The method of producing a composite substrate according to claim 19, further comprising performing a surface treatment prior to providing the second layer of stretchable and/or flexible material.

21. The method of producing a composite substrate according to claim 20, wherein the surface treatment is a plasma treatment.

22. The method of producing a composite substrate according to claim 20, further comprising patterning the second layer of stretchable and/or flexible material.

23. The method of producing a composite substrate according to claim 1, further comprising providing a local stiffener.

24. The method of producing a composite substrate according to claim 23, wherein the local stiffener is rigid or flexible.

25. The method of producing a composite substrate according to claim 23, wherein the local stiffener is provided by locally increasing the thickness of the stretchable and/or flexible material.

26. The method of producing a composite substrate according to claim 25, wherein the locally increasing of the thickness is achieved by moulding techniques.

27. The method of claim 1, wherein the providing of a stretchable and/or flexible material on top of and in between the patterned features comprises providing a stretchable and/or flexible material to cover substantially all the top surface and sidewall of the patterned features.

28. The method of claim 1, wherein the stretchable and/or flexible material comprises at least one of the following:

silicone, latex, polyurethane, rubber, thermoplastic elestomers (TPE), and polyimide.

29. A method of producing a composite substrate, comprising:

providing a sacrificial layer;

providing a patterned resist layer on the flexible sacrificial layer;

depositing a conducting layer in between the patterned resist layer such that the conducting layer is also patterned;

removing the resist layer;

providing a stretchable and/or flexible material on top of and between patterned features of the conducting layer; and

removing the sacrificial layer.