Switchable inductance

• US 20050024178A1
• Filed: 07/30/2004
• Published: 02/03/2005
• Est. Priority Date: 08/01/2003
• Status: Active Grant

• Current Assignee: Stmicroelectronics France (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SA (STMicroelectronics NV)
• Inventors: Saias, Daniel, Ancey, Pascal
• Granted Patent: US 7,259,649 B2
• Time in Patent Office: Days
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 2021/125 Printed variable inductor with taps, e.g. for VCO
• CPC Class Codes: H01F 21/12 discontinuously variable, e.g. tapped
• CPC Class Codes: H01H 2061/006 Micromechanical thermal relay
• CPC Class Codes: H01H 61/04 wherein the thermally-sensitive member is only heated directly
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• 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

Abstract

A switchable inductance that can be formed in an integrated circuit, including a spiral interrupted between two first points connected to two terminals via two metallizations running one above the other, one of the two metallizations being deformable; a hollowing between the two metallizations; and a switching device capable of deforming the deformable metallization to separate or to put in contact said two metallizations.

Claims

1. A switchable inductance that can be formed in an integrated circuit, comprising:

a spiral interrupted between two first points connected to two terminals via two metallizations running one above the other, one of the two metallizations being deformable;

a hollowing between the two metallizations; and

a switching device capable of deforming the deformable metallization to separate or to put in contact said two metallizations.

2. The inductance of claim 1, wherein the switching device comprises:

a cavity formed in a substrate;

a conductive beam in suspense above the cavity, the conductive beam being the deformable metallization;

a conductive strip placed at a bottom of the cavity, the conductive strip being the other one of said metallizations; and

means for deforming the beam capable of putting in contact the beam and the conductive strip.

3. The inductance of claim 2, wherein the beam deformation means comprise multilayer blocks placed on the beam, each block comprising a conductive layer placed between an insulating layer and a layer of a material having an expansion coefficient different from that of the beam, activation means being capable of conducting a current in the conductive layer of each block to heat the beam and said material layer of each block.

4. The inductance of claim 1, comprising a second spiral, the second spiral being interrupted between two second points connected to said terminals, the external spiral being interrupted and connected to connection terminals.

5. The inductance of claim 4, wherein the inductance comprises additional spirals, each of which is associated with another spiral by crossed metallizations, one of which is deformable and associated with one of the switching devices.