Semiconductor device

• US 20060267771A1
• Filed: 05/25/2006
• Published: 11/30/2006
• Est. Priority Date: 05/27/2005
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Inoue, Hiroki, Atsumi, Tomoaki, Shionoiri, Yutaka
• Granted Patent: US 7,923,796 B2
• Time in Patent Office: Days
• US Class Current: 340/572.100
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: H01L 21/485 Adaptation of interconnections, e.g. engineering charges, repair techniques

Abstract

It is an object of the present invention to provide a semiconductor device in which an arrangement area of capacitance can be reduced and resonance frequency can be easily adjusted. The semiconductor device includes an antenna and a resonance circuit including a capacitor connected to the antenna in parallel where the capacitor is formed by connecting x pieces of first capacitor (x is an arbitrary natural number), y pieces of second capacitor (y is an arbitrary natural number), and z pieces of third capacitor (z is an arbitrary natural number) in parallel; and the first capacitor, the second capacitor, and the third capacitor have different capacitance values from each other. It is preferable that each of the first capacitor, the second capacitor, and the third capacitor be a MIS capacitor. Further, at least one of the first capacitor, the second capacitor, and the third capacitor is preferably formed by connecting a plurality of capacitors in parallel.

Claims

1. A semiconductor device comprising a resonance circuit, said resonance circuit comprising:

an antenna; and

a capacitor connected to the antenna in parallel,

wherein the capacitor comprises a plurality of capacitors connected in parallel,

wherein at least one of the plurality of the capacitors has a different capacitance value from at least another one of the plurality of capacitors; and

wherein at least one capacitor selected form the plurality of the capacitors is electrically separated from the capacitor of the resonance circuit so that a capacitance value of the capacitor in the resonance circuit is adjusted.

2. The semiconductor device according to claim 1, wherein each of the plurality of the capacitors is a MIS capacitor.

3. A semiconductor device comprising a resonance circuit, said resonance circuit comprising:

an antenna; and

a capacitor connected to the antenna in parallel,

wherein the capacitor comprises x pieces of first capacitor (x is an arbitrary natural number), y pieces of second capacitor (y is an arbitrary natural number), and z pieces of third capacitor (z is an arbitrary natural number) connected in parallel,

wherein the first capacitor, the second capacitor, and the third capacitor have different capacitance values from each other, and

wherein at least one capacitor selected from x pieces of the first capacitor, y pieces of the second capacitor, and z pieces of the third capacitor is electrically separated from the capacitor of the resonance circuit so that a capacitance value of the capacitor of the resonance circuit is adjusted.

4. The semiconductor device according to claim 3, wherein each of the first capacitor, the second capacitor, and the third capacitor is a MIS capacitor.

5. The semiconductor device according to claim 3, wherein at least one of the first capacitor, the second capacitor, and the third capacitor comprises a plurality of capacitors connected in series.

6. A semiconductor device comprising a resonance circuit, said resonance circuit comprising:

an antenna;

a capacitor;

a first wiring; and

a second wiring,

wherein the capacitor comprises a plurality of capacitors connected in parallel,

wherein at least one of the plurality of the capacitors has different capacitance values from at least another one of the plurality of capacitors,

wherein each of the plurality of the capacitors comprises an insulating layer interposed between a semiconductor layer and a conductive layer,

wherein the semiconductor layer is electrically connected to the antenna through the first wiring,

wherein the conductive layer is electrically connected to the antenna through the second wiring, and

wherein at least one capacitor selected from the plurality of the capacitors is electrically separated from the capacitor of the resonance circuit so that a capacitance value of the capacitor of the resonance circuit is adjusted.

7. A semiconductor device comprising a resonance circuit, said resonance circuit comprising:

an antenna; and

a plurality of capacitors connected in parallel to the antenna;

wherein the resonance circuit further includes at least one capacitor which is electrically separated from the other capacitors.

8. The semiconductor device according to claim 7, wherein at least one of said plurality of capacitors has a different capacitance value from at least another one of said plurality of capacitors.

9. The semiconductor device according to claim 7, wherein each of the plurality of the capacitors is a MIS capacitor.