Reed contactor and process of fabricating suspended tridimensional metallic microstructure

• US 5,430,421 A
• Filed: 12/14/1993
• Issued: 07/04/1995
• Est. Priority Date: 12/15/1992
• Status: Expired due to Term

• Current Assignee: Asulab SA (The Swatch Group AG)
• Original Assignee: Asulab SA (The Swatch Group AG)
• Inventors: Simon, Jean-Luc, Bornand, Etienne
• Primary Examiner(s): Donovan, Lincoln
• Application Number:
  US08/166,359
• Time in Patent Office: 567 Days
• Field of Search: 335/151-153, 335/154
• US Class Current: 335/154
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 1/66 Contacts sealed in an evacuated or gas-filled envelope, e.g. magnetic dry-reed contacts
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 2036/0093 Micromechanical switches actuated by a change of the magnetic field

Abstract

A reed contactor includes a base plane comprising two distinct conducting zones. Two shafts of the contactor have the form of blades, each of which engages a base plane at the level of one of the conducting zones. One of the beams at least is supported on the base plane by means of a foot on which it is mounted in an overhanging manner. The contactor is formed by process comprising the steps of forming successively on a substrate an alternance of levels of photoresist and of metallization. At each step, the level of upper photoresist is configured to create in its thickness free growth spaces in which metal pins are formed by galvanic growth. The levels of photoresist situated under the last level of metallization play the role of sacrificial layers and allow the formation of suspended metallic structures.

Claims

1. Contactor including two conducting beams connected respectively to electrical connection means, said beams each comprising a distal extremity, said distal extremities being near each other and mobile with respect to each other between a first open position in which they are separated from each other by a space, and a second closed position in which they are in contact with each other, said contactor further comprising recall means for recalling said distal extremities towards said opened position, said beams being further realized at least partially in a magnetizable material such that when they are submitted to a magnetic induction field of sufficient intensity, said distal extremities are brought to said closed position, said contactor being characterized in that it comprises a base plane comprising two distinct electrically conducting zones, in that said beams engage said base plane at the level of said two conducting zones, and in that at least one of said beams is bound to said base plane by means of a foot on which it is mounted.

2. Contactor according to claim 1, characterized in that it comprises a cap which covers the beams and which is fixed to said base plane to form therewith a closed chamber, and in that said connection means are located on the exterior of said chamber.

3. A contactor comprising a planar base having first and second conducting zones on one face thereof, first and second conductive beams supported on said one face, each of said beams having a distal extremity, said distal extremities being near each other and at least one of said distal extremities being mobile with respect to the other between a first open position in which the distal extremities are separated from each other and a second closed position in which they contact each other, said beams comprising a magnetizable material whereby an applied magnetic field causes movement of said distal extremity of said first conductive beam from one of said positions to the other of said positions, said first conductive beam having a second extremity, a foot of conductive material for supporting said first conductive beam, said foot being bound at said second extremity to a surface of said first conductive beam that extends from said second extremity to the distal extremity of said first conductive beam, said foot extending normal to said surface of said first conductive beam and being bound to said first conducting zone whereby said first conductive beam is electrically connected to said first conducting zone through said foot, and said second conductive beam being electrically connected to said second conducting zone.

4. A contactor as claimed in claim 3 and further comprising a cap mounted to said one surface of said planar base to form a hermetically closed chamber in which said conductive beams are located, and electrical connection means external of said chamber and in electrical contact with said first and second conducting zones.

5. A contactor as claimed in claim 3 wherein said foot comprises multiple layers of thin films.

6. A contactor as claimed in claim 5 wherein at least one of said layers comprise a material different from material of others of said layers.

7. A contactor as claimed in claim 3 wherein said second conductive beam is bound to a second foot of electrically conductive material.

8. A contactor as claimed in claim 7 wherein said second foot is bound to said second conducting zone and extends normal to said second conductive beam and said one surface of said planar base.