CAPACITANCE DEVICE AND RESONANCE CIRCUIT

• US 20110163827A1
• Filed: 09/24/2009
• Published: 07/07/2011
• Est. Priority Date: 09/26/2008
• Status: Active Grant

• Current Assignee: Sony Chemical & Information Device Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Watanabe, Makoto, Yokota, Toshiaki, Habu, Kazutaka, Sato, Noritaka, Kanno, Masayoshi
• Granted Patent: US 8,736,401 B2
• Time in Patent Office: Days
• US Class Current: 333/185
• CPC Class Codes: H01G 4/232 electrically connecting two or more layers of a stacked or rolled capacitor
• CPC Class Codes: H01G 4/255 Means for correcting the capacitance value
• CPC Class Codes: H01G 4/30 Stacked capacitors H01G4/33 takes precedence
• CPC Class Codes: H01G 7/06 having a dielectric selected for the variation of its permittivity with applied voltage, i.e. ferroelectric capacitors electrets H01G7/02
• CPC Class Codes: H03H 2001/0085 Multilayer, e.g. LTCC, HTCC, green sheets inside PCB filters H05K
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence

Abstract

To suppress changes in capacitance due to displacement between electrodes opposing each other across a dielectric layer, thereby allowing stable manufacturing of a capacitance device having a desired capacitance.

The capacitance device according to the present invention is of a configuration including a dielectric layer (10), a first electrode (11) formed on a predetermined surface (10a) of the dielectric layer (10), and a second electrode (12) formed on a surface (10b) on the opposite side of the dielectric layer (10) from the predetermined surface (10a). The forms of the first and second electrodes (11, 12) are set so that even in the event that the first electrode (11) is relatively displaced regarding position in a predetermined direction as to the second electrode (12), the area of the opposing-electrode region between the first electrode (11) and to the second electrode (12) is unchanged.

Claims

1. A capacitance device comprising:

a dielectric layer;

a first electrode that is formed in a predetermined first shape on a predetermined surface of the dielectric layer; and

a second electrode that is formed on an opposite surface of the dielectric layer opposite to the predetermined surface, has a first region overlapping a projection pattern obtained by projecting the first electrode onto the opposite surface, and is formed in a second shape such that an area of the first region does not change even when the first electrode undergoes relative displacement in a predetermined direction within the predetermined surface.

2. The capacitance device according to claim 1, wherein:

the first electrode has a first electrode portion including an electrode region corresponding to the first region and extending in a first direction within the predetermined surface;

the second electrode has a second electrode portion including an electrode region corresponding to the first region and extending in a second direction crossing the first direction within the opposite surface; and

the first electrode portion and the second electrode portion are individually formed in such shapes that an area of the first region does not change even when the first electrode undergoes relative displacement with respect to the second electrode within the predetermined surface in the predetermined direction and in a direction orthogonal to the predetermined direction.

3. The capacitance device according to claim 2,

wherein the first direction and the second direction are orthogonal to each other.

4. The capacitance device according to claim 2,

wherein the first shape of the first electrode and the second shape of the second electrode are symmetric with respect to one of the predetermined direction and the direction orthogonal to the predetermined direction within the predetermined surface.

5. The capacitance device according to claim 1, wherein:

the first electrode has a first electrode portion including an electrode region corresponding to the first region and extending in a direction orthogonal to the predetermined direction within the predetermined surface; and

the second electrode has a second electrode portion including an electrode region corresponding to the first region and extending in a direction orthogonal to the predetermined direction within the opposite surface, the second electrode having a plurality of the first regions.

6. The capacitance device according to claim 1, wherein:

a shape of each of the surfaces of the dielectric layer on which the first electrode and the second electrode are formed is rectangular;

the first electrode and the second electrode have a first terminal portion and a second terminal portion for electrically externally connecting the first electrode portion and the second electrode portion, respectively; and

the first terminal portion and the second terminal portion are each provided along a long side of each of the surfaces and near the long side.

7. The capacitance device according to claim 1, further comprising:

a plurality of the dielectric layers;

wherein the plurality of the dielectric layers are layered via electrodes;

and wherein two electrodes sandwiching each of the dielectric layers are individually formed in such shapes that even when one of the two electrodes undergoes relative displacement in a predetermined direction with respect to the other electrode, an area of an overlapping region between the other electrode and a projection pattern obtained by projecting the one electrode onto the other electrode side does not change.

8. The capacitance device according to claim 1, wherein

at least one of the first electrode and the second electrode has an electrode portion, and a terminal portion for electrically externally connecting the electrode portion;

and

the electrode portion and the terminal portion define an opening.

9. The capacitance device according to claim 1, further comprising:

a first external terminal that is provided on a first side surface of the dielectric layer, and is connected to the first electrode; and

a second external terminal that is provided on a second side surface of the dielectric layer opposing the first side surface, and is connected to the second electrode,

wherein a placing direction of the first external terminal and the second external terminal crosses an opposing direction between the first side surface and the second side surface.

10. The capacitance device according to claim 1, further comprising:

a first external terminal that is provided on one side surface of the dielectric layer, and is connected to the first electrode; and

a second external terminal that is provided on the side surface of the dielectric layer so as to be separated by a predetermined distance from the first external terminal, and is connected to the second electrode.

11. The capacitance device according to claim 1, further comprising:

a third electrode that is formed in a predetermined third shape on the predetermined surface of the dielectric layer; and

a fourth electrode that is formed on the opposite surface of the dielectric layer opposite to the predetermined surface, has a second region overlapping a projection pattern obtained by projecting the third electrode onto the opposite surface, and is formed in a fourth shape such that an area of the second region does not change even when the third electrode undergoes relative displacement in a predetermined direction within the predetermined surface.

12. The Capacitance device according to claim 11, further comprising:

a first external terminal that is provided on a first side surface of the dielectric layer, and is connected to the first electrode;

a second external terminal that is provided on the first side surface of the dielectric layer so as to be separated by a predetermined distance from the first external terminal, and is connected to the second electrode;

a third external terminal that is provided on a second side surface of the dielectric layer opposing the first side surface, and is connected to the third electrode; and

a fourth external terminal that is provided on the second side surface of the dielectric layer so as to be separated by a predetermined distance from the third external terminal, and is connected to the fourth electrode.

13. The capacitance device according to claim 1, further comprising:

a third electrode that is formed on the opposite surface of the dielectric layer opposite to the predetermined surface, has a second region overlapping the projection pattern obtained by projecting the first electrode onto the opposite surface, and is formed in a third shape such that an area of the second region does not change even when the first electrode undergoes relative displacement in a predetermined direction within the predetermined surface.

14. The capacitance device according to claim 13, further comprising:

a first external terminal that is provided on a first side surface of the dielectric layer, and is connected to the first electrode;

a second external terminal that is provided on a second side surface of the dielectric layer opposing the first side surface, and is connected to the second electrode; and

a third external terminal that is provided on the second side surface of the dielectric layer so as to be separated by a predetermined distance from the second external terminal, and is connected to the third electrode.

15. The capacitance device according to claim 1, wherein the dielectric layer is formed of a ferromagnetic material, and wherein the capacitance thereof changes in accordance with externally applied control signals.

16. A resonance circuit comprising:

a resonance capacitor including a dielectric layer, a first electrode that is formed in a predetermined first shape on a predetermined surface of the dielectric layer, and a second electrode that is formed on an opposite surface of the dielectric layer opposite to the predetermined surface, has a first region overlapping a projection pattern obtained by projecting the first electrode onto the opposite surface, and is formed in a second shape such that an area of the first region does not change even when the first electrode undergoes relative displacement in a predetermined direction within the predetermined surface; and

a resonance coil connected to the resonance capacitor.