The present invention relates to an EMI (Electromagnetic Disturbance) filer, particularly to a multi-layer electric shock protection EMI filter device which integrates a capacitor and an electric shock protection device and has optimized discharge characteristics, and a manufacturing method thereof and a manufacturing method thereof.
With demands of minimizing electronic components used in digital electronic devices such as mobile phones, a capacitor is developed toward a multi-layer structure. The capacity of a multi-layer ceramic capacitor is proportional to the dielectric constant of dielectric layer material constituting the capacitor or the number of the dielectric layers, and is inversely proportional to the thickness of each dielectric layer. Therefore, it is an objective of the industry to meet miniaturization demands, increase the dielectric constant of the material, and reduce the thickness of the dielectric layer, thereby increasing the number of layers.
Said electric shock protection device is provided in the area which is likely to be damaged by electric shock due to abnormal voltage electric shock (e.g. lightning surge or static electricity). When the abnormal voltage (e.g. surge) is applied, the abnormal voltage causes gas discharge and electricity consumption, which prevents electronic components on the printed circuit board from being damaged due to abnormal voltage.
Currently the capacitor and electric shock protection device are individually manufactured and provided independently. In response to more and more 3C product functions, higher frequency, and requirements for superior features, the space of components within a printed circuit board (PCB) is obviously inadequate.
In view of the problem that conventional capacitors and electric shock protection devices need to be manufactured individually and set up separately, resulting in insufficient printed circuit board space, after a long period of research in conjunction with improvement on the aforementioned deficiency, the present invention is eventually presented by the inventor.
Accordingly, it is an objective of the present invention to provide a multi-layer electric shock protection EMI filter device and a manufacturing method thereof, which integrates a capacitor and an electric shock protection device into a single device.
According to the multi-layer electric shock protection EMI filter device and the manufacturing method thereof in the present invention, it can be implemented by integrating a capacitor and an electric shock protection device, or by integrating two capacitors and an electric shock protection device. This is a secondary objective of the present invention.
According to the multi-layer electric shock protection EMI filter device and the manufacturing method thereof in the present invention, the multi-layer electric shock protection EMI filter device is manufactured by using the ceramic green sheet as dielectric materials, stacking the dielectric material, metal layers, and an electric shock protection layer sequentially with intervals, and then performing a low temperature cofire process. This is another objective of the present invention.
According to the multi-layer electric shock protection EMI filter device and the manufacturing method thereof in the present invention, a tripping layer is provided between two metal wires on the electric shock protection device. The tripping layer is made of a mix of SiC (Silicon Carbide) and glass materials. After the low temperature cofire process, the tripping layer becomes a compound structure of a SiC body and an air gap, which achieves the effect of device integration and performance optimization. This is a further objective of the present invention.
The detailed structure, application principles, functions and effectiveness of the present invention will be apparent with reference to the following description in conjunction with the accompanying drawings.
A multi-layer electric shock protection EMI filter device 1000 in the present invention, as shown in
As shown in the figure, the multi-layer electric shock protection EMI filter device 1000 forms a first metal layer 112 on the upper surface of a first ceramic dielectric material layer 110. The first metal layer 112 includes a first metal layer A 1121 with one end connected to the first end electrode 401, and a first metal layer B 1122 with one end connected to the second end electrode 402; specifically, the opposite end of the first metal layer A 1121 is isolated from the opposite end of the first metal layer B 1122.
A second ceramic dielectric material layer 114 is formed above the first metal layer 112 to completely cover the first metal layer 112. A part of the second ceramic dielectric material layer 114 is filled up between the first metal layer A 1121 and the first metal layer B 1122.
A second metal layer 116, which is formed on the upper surface of the second ceramic dielectric material layer 114, includes a second metal layer A 1161 with one end connected to the first end electrode 401, and a second metal layer B 1162 with one end connected to the second end electrode 402; specifically, the opposite end of the second metal layer A 1161 is isolated from the opposite end of the second metal layer B 1162.
The isolated position of the second metal layer A 1161 and the second metal layer B 1162 is offset from the isolated position of the first metal layer A 1121 and the first metal layer B 1122 and is not in the same vertical line, such that the first metal layer 11.2 and the second metal layer 116 constitute the lower capacitor 100.
A third ceramic dielectric material layer 118 is formed above the second metal layer 116 to completely cover the second metal layer 116. A part of the third ceramic dielectric material layer 118 is filled up between the second metal layer A 1161 and the second metal layer B 1162.
An electric shock protection layer 201 used as the electric shock protection device 200 is formed on the upper surface of the third ceramic dielectric material layer 118, and provided with two metal wires 201A and 201B. One end of the two metal wires 201A and 201B are connected to the first end electrode 401 and the second end electrode 402 respectively. A tripping layer 202 is provided above the opposite end of the two metal wires 201A and 201B. The tripping layer 202 is a mix of SiC and glass, and is filled up between the two metal wires 201A and 201B.
A fourth ceramic dielectric material layer 150 is formed above the electric shock protection layer 201 to completely cover the electric shock protection layer 201.
A third metal layer 152, which is formed on the upper surface of the fourth ceramic dielectric material layer 150, includes a third metal layer A 1521 with one end connected to the first end electrode 401, and a third metal layer B 1522 with one end connected to the second end electrode 402; specifically, the opposite end of the third metal layer A 1521 is isolated from the opposite end of the third metal layer B 1522.
A fifth ceramic dielectric material layer 154, which is formed above the third metal layer 152 to completely cover the third metal layer 152. A part of the fifth ceramic dielectric material layer 154 is filled up between the third metal layer A 1521 and the third metal layer B 1522.
A fourth metal layer 156, which is formed on the upper surface of the fifth ceramic dielectric material layer 154, includes a fourth metal layer A 1561 with one end connected to the first end electrode 401, and a fourth metal layer B 1562 with one end connected to the second end electrode 402; specifically, the opposite end of the fourth metal layer A 1561 is isolated from the opposite end of the fourth metal layer B 1562.
A sixth ceramic dielectric material layer 158, which is formed above the fourth metal layer 156 to completely cover the fourth metal layer 156. A part of the sixth ceramic dielectric material layer 158 is filled up between the fourth metal layer A 1561 and the fourth metal layer B 1562.
The isolated position of the third metal layer A 1521 and the third metal layer B 1522 is offset from the isolated position of the fourth metal layer A 1561 and the fourth metal layer B 1562, and is not in the same vertical line, such that the third metal layer 152 and the fourth metal layer 156 constitute the upper capacitor 300.
According to the multi-layer electric shock protection EMI filter device in the present invention, the electric shock protection device 200 is disposed between the lower capacitor 100 and the upper capacitor 300. When the surge generated by electrostatic discharges, high voltage can be discharged by the electric shock protection device 200 for protecting the circuit. Also, placing the electric shock protection device 200 between the lower capacitor 100 and the upper capacitor 300 can prevent the device from bending during sintering.
Each of the aforementioned ceramic dielectric material layer 110, 114, 118, 150, 154, 158 may be made of Class I or Class II ceramic dielectric material with COG, X_R, Z_U, Y_V code. Each of metal layers 112, 116, 152, 156, 201A, 201B may be made of silver (Ag) or silver/palladium (Ag/Pd) material.
Steps of manufacturing a multi-layer electric shock protection EMI filter device according to the present invention include:
Step A: Forming a first dielectric material layer ceramic green sheet 501 (as shown in
Step B: Printing the first metal layer 112 on the upper surface of the first dielectric material layer ceramic green sheet 501, wherein the elongated first metal layer A 112 of the first metal layer 112 and one end of the short first metal layer B 1121 are cut to be aligned with edges of the first dielectric material layer ceramic green sheet 501 respectively, and a gap 1123 is formed between the opposite end thereof (as shown in
Step C: Providing a second dielectric material layer ceramic green sheet 502 above the first metal layer 112, and enabling the gap 1123 between the first metal layer A 1121 and the first metal layer B 1121 of the first metal layer 112 to be filled up (as shown in
Step D: Printing the second metal layer 116 on the upper surface of the second dielectric material layer ceramic green sheet 502, wherein the short second metal layer A 1161 of the second metal layer 116 and one end of the elongated second metal layer B 1162 are cut to be aligned with edges of the second dielectric material layer ceramic green sheet 502 respectively, and a gap 1163 is formed in the opposite end thereof (as shown in
Step E: Providing a third dielectric material layer ceramic green sheet 503 above the second metal layer 116, and enabling the gap between the second metal layer. A 1161 and the second metal layer B 1162 of the second metal layer 116 to be filled up (as shown in
Step F: Printing the electric shock protection layer 201 on the upper surface of the third dielectric material layer ceramic green sheet 503, and enabling one end of the two metal wires 201A and 201B of the electric shock protection layer 201 to be cut and aligned with edges of the third dielectric material layer ceramic green sheet 503, and a tripping layer 202 above the opposite end thereof is a mix of SiC and glass (as shown in
Step G: Providing a fourth dielectric material layer ceramic green sheet 504 above the electric shock protection layer 201 (as shown in
Step H: Printing the third metal layer 152 on the upper surface of the fourth dielectric material layer ceramic green sheet 504, and enabling an elongated third metal layer A 1521 of the third metal layer 152 and one end of a short third metal layer B 1522 to be cut and aligned with edges of the fourth dielectric material layer ceramic green sheet 504 respectively, and a gap 1523 is formed in the opposite end thereof (as shown in
Step I: Providing a fifth dielectric material layer ceramic green sheet 505 above the third metal layer 152, and enabling the gap between the third metal layer A 1521 and the third metal layer B 1522 of the third metal layer 152 to be filled up (as shown in
Step J: Printing the fourth metal layer 156 on the upper surface of the fifth dielectric material layer ceramic green sheet 505, wherein a short fourth metal layer A 1561 of the fourth metal layer 156 and one end of an elongated fourth metal layer B 1562 are cut to be aligned with edges of the fifth dielectric material layer ceramic green sheet 505 respectively, and a gap 1563 is formed in the opposite end thereof (as shown in
Step K. Providing a sixth dielectric material layer ceramic green sheet 506 above the fourth metal layer 156, and enabling the gap between the fourth metal layer A 1561 and the fourth metal layer B 1562 of the fourth metal layer 156 to be filled up (as shown in
Step L: After a low temperature cofire process is performed, as shown in
Step M: Finally, forming the first end electrode 401 and the second end electrode 402 on the overall side (as shown in
Accordingly, in the multi-layer electric shock protection EMI filter device manufactured through the above process in the present invention, after a low temperature cofire process, heterogeneous materials such as dielectric material (ceramic dielectric material layer), metal, SiC, and glass can be cofired into a whole, such that the lower capacitor 100, the electric shock protection device 200 and the upper capacitor 300 can be integrated into a whole.
Please refer to both
When the multi-layer electric shock protection EMI filter device in the present invention is implemented, as also shown in
When the multi-layer electric shock protection EMI filter device in the present invention is implemented, as also shown in
As above, the multi-layer electric shock protection EMI filter device and a manufacturing method thereof according to the present invention can truly achieve the integration of a capacitor with an electric shock protection device and the optimization of electrostatic discharge characteristics. This is not disclosed and used in public, and is compliant with provisions of the Patent Law. It would be appreciated if the committee could kindly approve and grant a patent earlier for the benefit of society.
It should be noted that the described are preferred embodiments, and that changes and modifications may be made to the described embodiments without departing from the scope of the invention as disposed by the appended claims.