Packaging of a micro-magnetic switch with a patterned permanent magnet

• US 7,250,838 B2
• Filed: 04/04/2005
• Issued: 07/31/2007
• Est. Priority Date: 01/08/2002
• Status: Expired due to Fees

• Current Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Original Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Inventors: Shen, Jun, Godavarti, Prasad S.
• Primary Examiner(s): Enad; Elvin
• Assistant Examiner(s): Rojas; Bernard
• Application Number:
  US11/097,390
• Publication Number:
  US 20060055491A1
• Time in Patent Office: 848 Days
• Field of Search: 335/78, 200/181
• US Class Current: 335/78
• CPC Class Codes: H01H 2050/007 Relays of the polarised type, e.g. the MEMS relay beam having a preferential magnetisation direction
• CPC Class Codes: H01H 50/005 using micromechanics

Abstract

A method and apparatus for packaging a plurality of micro-magnetic switches is described. A bonded substrate structure includes a first substrate, a second substrate, and a magnetic layer. The first substrate has a plurality of cantilevers formed thereon. The second substrate has a first surface that is bonded to the first substrate. Each cantilever of the plurality of cantilevers on the first substrate is housed in a corresponding space formed between the first substrate and the second substrate. The magnetic layer is formed on a second surface of the first and/or second substrate to induce a magnetization in a magnetic material of each housed cantilever. The bonded substrate structure is singulated to form a plurality of separate micro-magnetic switch packages. Each micro-magnetic switch package of the plurality of micro-magnetic switch packages includes at least one housed cantilever.

Claims

1. A method for packaging a plurality of micro-magnetic switches, comprising:

(A) providing a first substrate having a plurality of cantilevers spaced apart on a first surface of the first substrate, each cantilever residing in a corresponding cavity in the first surface the first substrate;

(B) bonding a first surface of a second substrate to the first surface of the first substrate, wherein each cantilever is thereby housed in a corresponding space formed between the first and second substrates, the space corresponding to each cantilever formed at least in part by the corresponding cavity in the first surface of the first substrate; and

(C) forming a magnetic layer on at least one of the first and second substrates to induce a magnetization in a magnetic material of each housed cantilever.

2. The method of claim 1, further comprising:

(D) singulating the bonded substrate structure to form a plurality of separate micro-magnetic switch packages, each micro-magnetic switch package of the plurality of micro-magnetic switch packages including at least one housed cantilever.

3. The method of claim 1, wherein step (C) comprises patterning the magnetic layer.

4. The method of claim 3, wherein said patterning step comprises screen printing the magnetic layer.

5. The method of claim 3, wherein said patterning step comprises lithographic processing to deposit the magnetic layer.

6. The method of claim 3, wherein said patterning step comprises sputtering the magnetic layer.

7. The method of claim 3, wherein said patterning step comprises electroplating the magnetic layer.

8. The method of claim 3, wherein said patterning step comprises laminating the magnetic layer.

9. The method of claim 8, wherein step (A) comprises:

providing the first substrate having an imbedded plurality of coils in a dielectric material of the first substrate.

10. The method of claim 9, wherein step (A) further comprises:

providing the first substrate having the plurality of cantilevers formed such that each cantilever of the plurality of cantilevers is located adjacent to a corresponding coil of the imbedded plurality of coils.

11. The method of claim 1, wherein the space corresponding to each cantilever is formed by the corresponding first cavity in the first surface of the first substrate and a corresponding second cavity in the first surface of the second substrate, wherein step (B) comprises:

positioning the first and second substrates such that each cantilever is housed in the corresponding first cavity and second cavity.

12. The method of claim 1, wherein step (C) comprises:

forming the magnetic layer on a second surface of the first substrate.

13. The method of claim 1, wherein step (C) comprises:

forming the magnetic layer on a second surface of the second substrate.

14. An apparatus for packaging a plurality of micro-magnetic switches, comprising:

a bonded substrate structure having

a first substrate with a plurality of cantilevers formed thereon,

a second substrate with a first surface that is bonded to the first substrate,

wherein each cantilever of the plurality of cantilevers on the first substrate is housed in a corresponding space formed between said first substrate and said second substrate, wherein a first surface of the first substrate has a plurality of cavities formed therein, wherein the space corresponding to each cantilever is formed at least in part by a corresponding cavity of the plurality of cavities, and

a magnetic layer formed on at least one of said first substrate and said second substrate to induce a magnetization in a magnetic material of each housed cantilever;

wherein the bonded substrate structure is singulated to form a plurality of separate micro-magnetic switch packages, each micro-magnetic switch package of the plurality of micro-magnetic switch packages including at least one housed cantilever.

15. The apparatus of claim 14, wherein the magnetic layer is patterned to form a plurality of permanent magnets, each permanent magnet of the plurality of permanent magnets included in a corresponding micro-magnetic switch package of the plurality of micro-magnetic switch packages, wherein each permanent magnet of the plurality of permanent magnets induces the magnetization in the magnetic material of a corresponding housed cantilever.

16. The apparatus of claim 14, wherein a plurality of coils are imbedded in a dielectric material of the first substrate.

17. The apparatus of claim 16, wherein the plurality of cantilevers are formed on a surface of the first substrate such that each cantilever of the plurality of cantilevers is located adjacent to a corresponding coil of the imbedded plurality of coils.

18. The apparatus of claim 16, wherein the first surface of the second substrate has a second plurality of cavities formed therein, wherein the space corresponding to each cantilever is formed by the corresponding cavity of the first plurality of cavities and a corresponding second cavity of the second plurality of cavities.

19. The apparatus of claim 14, wherein the magnetic layer is formed on a second surface of the first substrate.

20. The method of claim 14, wherein the magnetic layer is formed on a second surface of the second substrate.