MEMS DEVICES ON FLEXIBLE SUBSTRATE

• US 20170073215A1
• Filed: 05/11/2015
• Published: 03/16/2017
• Est. Priority Date: 05/28/2014
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Bergeron, Phillip J., Lunceford, Brent D., Geissinger, John D., Gundel, Douglas B., Mooney, Justine A., Palaniswamy, Ravi, Foo, Siang Sin
• Granted Patent: US 10,207,916 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2207/053 of movable structures
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: B81C 1/00182 Arrangements of deformable or non-deformable structures, e.g. membrane and cavity for use in a transducer

Abstract

A flexible film including one or more MEMS elements and articles including the flexible film are described. The flexible film includes a polymer layer between two metal layers with one of the metal layers containing a perforation. The polymer layer includes voided regions that allow for relative movement of the two metal layers.

Claims

1. A flexible film, comprising:

a first metallic layer having a first outer major surface and a first inner major surface;

a first polymer layer adjacent the first metallic layer, the first inner major surface facing the first polymer layer;

a second metallic layer having a second outer major surface and a second inner major surface, the second metallic layer disposed adjacent the first polymer layer opposite the first metallic layer, the second inner major surface facing the first polymer layer,

wherein the flexible film includes one or more MEMS elements, each MEMS element including;

a first metallic region in the first metallic layer, the first metallic region including a first perforation;

a first voided region in the first polymer layer; and

a second metallic region in the second metallic layer, the second metallic region including a portion that is capable of a movement relative to the first metallic region.

2. The flexible film of claim 1, wherein the first voided region is aligned with the first perforation such that a first continuous open region extends between the first outer major surface of the first metallic layer to the second inner major surface of the second metallic layer.

3. The flexible film of claim 2, wherein the second metallic region includes a pattern aligned with the first voided region such that the first continuous open region extends between the first outer major surface of the first metallic layer to the second outer major surface of the second metallic layer.

4. The flexible film of claim 1, wherein the first perforation includes 1 to about 100 holes and each hole has a diameter between about 30 microns and about 200 microns.

5. The flexible film of claim 1, wherein each MEMS element further includes one or more vias extending from the second metallic layer to the first metallic layer.

6. The flexible film of claim 1, wherein each MEMS element is selected from the group consisting of a spring resonator, a serpentine resonator, a fixed-guided-fixed resonator, a cantilever beam, a clamped membrane and an inter-digitated comb-drive resonator.

7. The flexible film of claim 1, further comprising:

a second polymer layer adjacent the second metallic layer opposite the first polymer layer;

a third metallic layer having a third outer major surface and a third inner major surface, the third metallic layer disposed adjacent the second polymer layer opposite the second metallic layer, the third inner major surface facing the second polymer layer;

wherein each MEMS element further includes;

a second voided region in the second polymer layer,

and a third metallic region in the third metallic layer, the third metallic region including a second perforation.

8. The flexible film of claim 7, wherein the second voided region is aligned with the second perforation such that a second continuous open region extends between the third outer major surface of the third metallic layer to the second outer major surface of the second metallic layer.

9. The flexible film of claim 1, wherein the movement is in a direction substantially normal to the second outer major surface.

10. The flexible film of claim 1, wherein the movement is substantially in a plane containing the second outer major surface.

11. The flexible film of claim 1, wherein the one or more MEMS elements is a plurality of MEMS elements.

12. The flexible film of claim 1, wherein the first outer major surface is either a first free standing surface or is immediately adjacent a first outer polymeric layer or a first adhesive layer and the second outer major surface is either a second free standing surface or is immediately adjacent a second outer polymeric layer or a second adhesive layer.

17. A roll of the flexible film of claim 1.

18. An article comprising a surface and the flexible film of claim 1, wherein the flexible film is conformably attached to the surface.

19. The flexible film of claim 1, wherein the first polymer layer includes a polymer selected from the group consisting of polyimide, polycarbonate, polyethylene terephthalate, benzocyclobutene polymer, liquid crystal polymer and polydimethylsiloxane.

20. The flexible film of claim 1, wherein at least one of the first metallic layer and the second metallic layer includes a metal selected from the group consisting of copper, nickel, chromium, titanium, aluminum, gold, silver, beryllium and alloys thereof.

13. An article comprising:

a three-dimensional object having a non-planar surface; and

a continuous film conformably attached to the non-planar surface, the continuous film including a polymer layer and one or more MEMS elements, each of the one or more MEMS elements including;

a first metallic layer having a first outer major surface and a first inner major surface, the first metallic layer disposed adjacent the polymer layer, the first inner major surface facing the polymer layer, the first metallic layer including a first perforation;

a first voided region in the polymer layer;

a second metallic layer having a second outer major surface and a second inner major surface, the second metallic layer disposed adjacent the polymer layer opposite the first metallic layer, the second inner major surface facing the polymer layer,

wherein the first voided region is aligned with the first perforation such that a continuous open region extends between the first outer major surface of the first metallic layer to the second inner major surface of the second metallic layer and wherein a portion of the second metallic layer is capable of a movement relative to the first metallic layer.

14. The article of claim 13, wherein the second metallic layer includes a pattern aligned with the first voided region such that the continuous open region extends between the first outer major surface of the first metallic layer to the second outer major surface of the second metallic layer.

15. The article of claim 13, wherein the three-dimensional object is a parallelepiped and the one or more MEMS elements includes a plurality of MEMS accelerometers, each MEMS accelerometer attached to a distinct face of the parallelepiped.

16. The article of claim 15, wherein the parallelepiped is a cube and the plurality of MEMS accelerometers includes three to six MEMS accelerometers.