1. Field of Invention
The present invention relates to a capacitor and an electric energy storage device. More particularly, the present invention relates to a parallel plate magnetic capacitor and an electric energy storage device.
2. Description of Related Art
Conventionally, parallel plate capacitors are structured using two conductive plates with dielectric material between the plates. The capacitance of the parallel plate capacitor can be calculated using the standard equation (1) and the electric energy corresponding to the capacitance can be calculated using the standard equation (2):
wherein C is the capacitance of the parallel plate capacitor, e0 is the dielectric constant of free space (8.85×10−12), ek is the dielectric constant of the material between the parallel plates, A is the interface area of the parallel plate, r is the distance between the parallel plates, E is the electric energy, and V is the applied voltage. Equation (1) showed that the capacitance of a parallel plate capacitor is proportional to the interface area of the parallel plate. For example, please refer to
The structure of the parallel capacitor 100 mentioned above, one would have to increase the area of the parallel plates in order to increase the total capacitance of the parallel capacitor, assuming the ek and r stays the same. Therefore it is a trade off between capacitance and the size of the capacitor, introducing a bottleneck to increase the capacitance while keeping the size of the parallel plate capacitor the same.
For the forgoing reasons, there is a need for a new parallel plate capacitor with a new structure to increase the capacitance while maintaining the overall volume of the capacitor.
In accordance with one embodiment, a magnetic capacitor (Mcap) is provided. The magnetic capacitor includes a first conductive magnetic metal, a second conductive magnetic metal and a dielectric material. The first conductive magnetic metal has a first upper finger located on an upper plane and a first lower finger located on a lower plane, in which the first upper finger is electrically connected to the first lower finger. The second conductive magnetic metal has a second upper finger and a second lower finger electrically connected with each other. The second upper finger is located on the upper plane such that the second upper finger is next to the first upper finger to form a first interface and on top of the first lower finger to form a second interface. The second lower finger is located on the lower plane such that the second lower finger is next to the first lower finger to form a third interface and below the first upper finger to form a fourth interface. The dielectric material is located in the first interface, the second interface, the third interface, and the fourth interface.
In accordance with another embodiment, a magnetic capacitor (Mcap) is provided. The magnetic capacitor (Mcap) includes two first pillar electrodes, two second pillar electrodes and a dielectric layer. The two first pillar electrodes electro-connect with each other and are located at right corner of a first plane and left corner of a second plane respectively. The two second pillar electrodes electro-connect with each other and are located at left corner of the first plane and right corner of the second plane respectively. The dielectric layer is located between the first pillar electrodes and the second pillar electrodes, such that the first pillar electrodes and the second pillar electrodes form capacitances therebetween.
It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
Please refer to
The second conductive magnetic metal structure 204 is composed of a second upper finger 218 and a second lower finger 220 electrically connected together. The second upper finger 218 is located on the upper plane 212 such that the second upper finger 218 is next to the first upper finger 208, which the side surface 222 of the first upper finger 208 and the side surface 224 of the second upper finger 218 forms a first interface 226. Furthermore, the second upper finger 218 is also on top of the first lower finger 210, which the bottom surface 228 of the second upper finger 218 and the top surface 230 of the first lower finger 210 forms a second interface 232.
Similarly, the second lower finger 220 is located on the lower plane 214, next to the first lower finger 210, and on below the first upper finger 208. Therefore, the second lower finger 220 forms a third interface 234 and a fourth interface 236 with the first upper finger 208 and the first lower finger 210.
The dielectric layer 206 is located between all the interfaces. Each interface 226, 232, 234, and 236 introduces a first capacitance 238, a second capacitance 240, a third capacitance 242, and a fourth capacitance 244, respectively. Therefore, the total capacitance introduced by the capacitor with the interfaces 226, 232, 234, and 236 is the sum of the capacitances 238, 240, 242, and 244. For example, if each interface introduces 4 units of capacitance, then when a voltage difference is applied between the first conductive magnetic metal structure 202 and the second conductive magnetic metal structure 204, the total capacitance introduced by the four interfaces 226, 232, 234, and 236 is 16 units.
In addition, when the first conductive magnetic metal structure 202 and the second conductive magnetic metal structure 204 are electrically biased, they would have magnetic polarization therein, in which the arrows shown in
The parallel capacitor structure may be expanded further as illustrated by
In order to illustrate that for the two parallel plate capacitors with the same dimension, namely capacitor 100 and capacitor 200, capacitor 200 introduces more capacitance than capacitor 100. Assuming the first upper finger 208 has a dimension of 2×2 (width=2 units, depth=2 units) and each finger in capacitor 200 has the same dimension. Therefore, the first capacitance 238 is proportional to 4 units2 and all other capacitances (capacitances 240, 242, 244 . . . etc) have values of 4 units2. Thus in
where eCMC is the coefficient due to Colossal Magnetic Capacitance effect
Please refer to
On the other hand, if the capacitance needed not to be increased, the volume of the capacitor can be reduced using the disclosed structure to obtain the same capacitance as a conventional parallel plate capacitor. Also, the disclosed capacitor may be expanded into multiple planes using the same structural geometry. From the above embodiment, a structural pattern can be observed. The structural pattern includes two first pillar electrodes located at opposite corners and different planes and two second pillar electrodes located on the remaining corners of the different planes. For example, if the first electrodes are located at the right corner of a first plane and the left corner of a second plane, then the second electrodes are located at the left corner of a first plane and the right corner of the second plane. A dielectric layer is located between the electrodes to form capacitances.
According to the above-mentioned structural pattern, a third plane may be added below the second plane to expand the capacitor. On the third plane, a third pillar electrode and a fourth pillar electrode are located thereon to form additional capacitances with each other and with the electrodes in the second plane.
According to the foregoing embodiments, the semiconductor material can be surrounded with magnetic layers to obtain colossal magneto capacitance where the dielectric constant of the material goes up to 109. In addition, the magnetic capacitor can be provided to reduce weight, volume, and cost, and be a high valued capacitor.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Number | Date | Country | Kind |
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0900432.6 | Jan 2009 | GB | national |
This application is a continuation-in-part of U.S. application Ser. No. 11/826,176, filed Jul. 12, 2007. The present application also claims priority to UK Application Serial Number 0900432.6, filed Jan. 12, 2009. All of these applications are incorporated herein by this reference.
Number | Date | Country | |
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Parent | 11826176 | Jul 2007 | US |
Child | 12368670 | US |