WO2018049669A1

WO2018049669A1 - Versatile pulse-based technique for packaging helical magnetic electrode

Info

Publication number: WO2018049669A1
Application number: PCT/CN2016/099294
Authority: WO
Inventors: 肖小驹
Original assignee: 深圳市辰驹电子科技有限公司
Priority date: 2016-09-19
Filing date: 2016-09-19
Publication date: 2018-03-22

Abstract

A versatile pulse-based MOA varistor for packaging a helical magnetic electrode. The varistor comprises a chip body (1) and helical electrodes (3). Silver-coated layers (2) are provided on two sides of the chip body. The helical electrodes are fixedly disposed on the silver-coated layers on the two sides of the chip body. The helical varistor exhibits superior electrical properties compared to conventional varistors, and are versatile in different types of applications, thus providing wide applicability, realizing adaptability to and protection for different pulse voltages, and improving performance of the varistor.

Description

Spiral magnetic electrode package omnipotent pulse technology

Technical field

The invention discloses an electronic component, in particular to a spiral magnetic electrode package all-round pulse technology, which comprises the technical fields of electronic circuits, pulsating currents, passive electronic components, packaging technologies and the like.

Background technique

It is well known that under high frequency conditions, the phenomenon that electrons tend to move on the surface of the wire is called the “skin effect.” At low frequencies, the skin effect has little effect on the conductive (impedance) characteristics of the wire, but with increasing frequency. The impedance of the wire will show that the impedance of the inductive effect wire changes due to the skin effect. Therefore, in reality, under the same surface area of the wire cross section, the power transmission capacity of the two cable lines is much higher than that of a single cable line. It is also the application of this principle, the work efficiency is very different after replacing one wire with two wires, but the amount of copper in the wire has not changed. Like the wires, there is also a skin effect in the cable. In addition, the presence of both magnetic and electric fields in the cable causes the impedance characteristics of the cable to have both an inductive effect and a capacitive effect. The magnetic field generated by the current through one wire will cause another The current in one wire is reduced, and if there is a potential difference between the two wires of the cable, an electric field is generated to cause a capacitive effect. Inductance and capacitance should also be noted that the cable can be equivalent to a cascade of many small inductors and small capacitors. The impedance of a cable can be equivalent to a combined network of inductors and capacitors.

The components used in electronic products - discrete (lead-inserted) passive components: resistors and capacitors are connected to the components by "L"-shaped metal lead wires. The chip is used to transmit current and energy in the circuit. To play the role of the module's own electrical performance parameters to achieve product design purposes.

Ordinary varistor uses a straight wire to conduct current from and out of the surface of the varistor. This way, the surface current of the varistor is concentrated at the lead position, causing excessive local current density. Before the varistor is turned on, its function is equivalent to a capacitor, and the alternating current flows over the ceramic chip and the silver layer. At the interface; the current density is the largest near the lead in the middle, which not only causes a temperature gradient in the direction of the flow in the chip, but also causes radial or circumferential cracks due to the difference in thermal expansion; and also causes the surface of the intermediate portion with the largest current density. The first barrier is reduced or damaged, which reduces the resistance of the pressure sensitive device to inrush current. Under the surge of the surge, the pressure sensitive device is turned on, and due to the effect of the skin effect, the current will concentrate on the periphery of the chip through the ceramic crystal. The actual cross-sectional area of the current through the valve plate becomes smaller, the resistance value of the current becomes larger, the voltage dropped on the valve plate increases, the energy consumption increases, and the temperature of the valve plate increases. At this time, the pressure sensitive damage point occurs mostly. The current passes through the relatively concentrated portion of the valve plate.

Summary of the invention

In view of the above-mentioned prior art discrete component leads are all in the "L" shape design, the present invention provides a new spiral magnetic electrode package omnipotent pulse technology, which uses a spiral wire electrode to solve Various problems caused by L-shaped electrodes.

The technical solution adopted by the invention to solve the technical problem is: a spiral magnetic electrode package all-round pulse technology, wherein the electrode is arranged on the body of the electronic component, the electrode is spiral, and when the electrode is energized, the magnetic field of the vertical axis The electron can be constrained so that the original electronic linear trajectory becomes a trajectory of spiral advancement. The action of the magnetic field causes the movement of the electron to become a spiral motion around the magnetic field line in the axial direction, and the spiral structure of the metal wire forms a uniform electromagnetic field under the energization condition. The principle of heating from the inside to the outside of the electromagnetic wave volume is used to heat the entire electronic component.

The technical solution adopted by the present invention to solve the technical problem thereof further includes:

The electronic component body is in the form of a sheet, and the spiral-shaped electrodes are fixedly disposed on both sides of the chip body.

The spiral wire electrode adopts a plane equiangular spiral or a plane constant velocity spiral.

The electronic component body has a column shape, and the spiral electrode is fixedly disposed at two ends of the chip body.

The spiral wire electrode adopts a double helix without a broken end.

The electronic component body is provided with a silver coating layer, and the spiral wire electrode is fixedly disposed on the silver coating layer.

The spiral wire electrode is disposed on the high conductive layer by soldering, and the high conductive layer is a silver coating layer or a conductive adhesive layer or a superconducting material layer.

The spiral electrode is embedded in the body of the electronic component.

The spiral electrodes on both sides of the electronic component body rotate in the same direction or rotate in different directions.

The spiral wire electrode adopts a hollow metal spiral wire or a flat metal spiral wire.

The beneficial effects of the invention are: spiral electrode structure of the chip wire The spiral electrode of the metal wire is distributed on both sides of the chip body:

1) Uniform distribution of current: a curved conductor can improve the heat dissipation and current density distribution uniformity of the tensile strength conductor, and has great benefits for the stability of the conductor device under cyclic loading. The current is obtained on the chip electrode. Evenly distributed surface temperature will also drop;

2) Draining and drying: Since the symmetric side of the chip is a symmetrical metal wire spiral electrode structure, a uniform electromagnetic field is formed under the energization condition, and the principle of electromagnetic wave volume heating from the inside to the outside is achieved;

3) The integrity of the silver level of the electrode: Due to the improvement of the tensile strength and the uniformity of the current density of the spiral metal electrode, the thermal expansion and contraction effect greatly reduces the "pull" destructive force on the surface of the chip's dense silver layer. The impact resistance and anti-aging leakage current are both fundamentally improved, and the early failure phenomenon formed is also significantly reduced.

About 80% of electronic components are passive components that do not have amplification or switching, but occupy more than 40% of the entire printed circuit board (PCB) / board (PWB) area, and in the production process More than 30% use the welding process, 90% of the pick and place operation, and the plane spiral inductor line The special high performance of the ring and the surface of the pressure sensitive semiconductor chip is welded: high current, high frequency, high energy and chip miniaturization, and the current direction of the current in the microcircuit is efficiently connected to the transmission mode, and the passive components are embedded and integrated in the future. The method and idea are provided to combine and integrate the three most basic passive components in the electrical system into the semiconductor device to form a multi-functional and powerful component system to achieve better performance and lower cost. , safer and more reliable product design purposes.

The invention will be further described with reference to the drawings and specific embodiments.

DRAWINGS

FIG. 1 is a schematic perspective view of a first embodiment of the present invention.

2 is a schematic perspective view of a second embodiment of the present invention.

FIG. 3 is a schematic diagram showing the current distribution of the surface of the electronic component when the invention is turned on.

FIG. 4 is a schematic diagram showing the current distribution of the chip body surface when the varistor is turned on in the prior art.

FIG. 5 is a schematic diagram of current distribution in an electronic component during turn-on of the present invention.

FIG. 6 is a schematic diagram showing the current distribution in the chip during the conduction of the varistor in the prior art.

7 is a comparison diagram of current conduction paths and lengths of a linear L-type electronic component in the prior art.

Fig. 8 is a view showing a comparison of a current conduction path and a length of a spiral electronic component in the present invention.

In the figure, 1-electron component body, 2-coated silver layer, 3-helical linear electrode, 4-electron distribution.

detailed description

This embodiment is a preferred embodiment of the present invention, and other principles and basic structures are the same as or similar to those of the present embodiment, and are all within the protection scope of the present invention.

The invention is a spiral magnetic electrode package all-round pulse technology. The core of the technology is that an electrode 3 is arranged on the electronic component body 1, and the electrode 3 has a spiral shape. When the electrode 3 is energized, the vertical axial magnetic field can constrain the electron. , so that the original electronic linear trajectory becomes a spiral forward trajectory, and the magnetic field makes The movement of the electrons becomes a spiral motion around the magnetic field lines in the axial direction. The spiral electrode structure of the metal wire forms a uniform electromagnetic field under the energization condition, and the principle of electromagnetic wave volume heating from the inside to the outside is heated, and the entire electronic component is heated. In this embodiment, the electronic component body 1 is provided with a silver coating layer 2, and the spiral electrode 3 is fixedly disposed on the silver coating layer 2. In the embodiment, the spiral electrode 3 is disposed on the silver coating layer 2 by welding. on. In a specific implementation, the spiral electrode 3 may be embedded in the electronic component body 1. In the present embodiment, the spiral electrodes 3 on both sides of the electronic component body 1 may be rotated in the same direction or may be rotated in different directions. The spiral wire electrode 3 is a hollow metal spiral wire or a flat metal spiral wire. In this embodiment, the lead end of the spiral electrode 3 is disposed at the edge of the electronic component body 1. In the specific implementation, the lead end of the spiral electrode 3 may be disposed at the center of the electronic component body 1, or a spiral. Any position in the linear electrode 3.

Referring to FIG. 1, in the embodiment, the electronic component body 1 is in the form of a sheet, the spiral electrode 3 is fixedly disposed on both sides of the chip body 1, and the spiral electrode 3 can adopt a plane equiangular spiral or a plane constant velocity spiral. .

Referring to FIG. 2, in the embodiment, the electronic component body 1 has a columnar shape, and the spiral-shaped electrode 3 is fixedly disposed at two ends of the electronic component body 1. The spiral-shaped electrode 3 is a double-spiral wire with no broken ends.

Referring to FIG. 3 to FIG. 6, it can be seen that the current distribution of the chip body surface and the body during turn-on can overcome the skin effect. Referring to FIG. 7 and FIG. 8, the current conduction path and length of the linear L-type electronic component and the spiral electronic component are compared. It is obvious that the spiral electronic component has a path length L'N>>linear L-type electron. The length of the path length of the component L'N, in the actual component size, the radius R>> thickness H, which is also the reason for the excellent performance of the spiral electronic components in the impact test 8/20us and power frequency boost test. One.

Efficient low-temperature mode of electron flow on the electrode surface: from the axial magnetic field on the ceramic grain boundary, except for adjustment In addition to the uniform function of the electrode surface of the chip, there is also an enhanced discharge means. The vertical axial magnetic field can constrain the secondary electrons, so that the original electronic linear trajectory becomes a spiral forward trajectory, and the action of the magnetic field causes the movement of the electron to become around the axial direction. The magnetic lines of force do spiral motion.

Since the symmetrical metal wire spiral electrode structure on the two sides of the chip forms a uniform electromagnetic field under the energization condition, the electromagnetic wave volume type is heated from the inside to the outside. The entire material is simultaneously heated. This is the so-called "volume heating" process. Microwave heating utilizes the principle of dielectric loss, and the loss factor of polar molecules such as water or ethanol is much larger than that of dry matter. The vast majority of the electromagnetic field release energy is absorbed by the water molecules in the material, due to the large amount of water in the material. The microwave energy is absorbed and converted into heat energy, so the temperature rise and evaporation of the material are simultaneously performed in the entire object. On the surface of the material, due to the evaporative cooling, the surface temperature of the material is slightly lower than the temperature of the inner layer, and at the same time, heat is generated inside the material, so that the internal steam is rapidly generated to form a pressure gradient. Consistency of direction If the initial moisture content of the material is very high and the pressure inside the material rises very quickly, the moisture may be removed from the material under the pressure gradient. It can be seen that during the microwave drying process, the temperature gradient and heat transfer are carried out. It is consistent with the steam pressure migration direction, which greatly improves the moisture migration condition during the drying process. Since the microwave energy penetrates into the heated object in an instant, no heat conduction process is required, and the microwave can be converted into the heat energy of the substance in a few minutes, so heating Fast speed and high drying efficiency are of course superior to conventional drying.

The spiral type lead structure in the present invention can effectively improve several problems:

1. Current uniformity and flow capacity:

The current can be efficiently extracted to the silver coating layer from a plurality of positions on the surface, thereby preventing excessive concentration of the surface current of the chip in the middle portion, reducing the temperature gradient of the surface, and reducing damage to the grain boundary of the middle surface. Thereby increasing the resistance of the varistor to the power frequency voltage. On the other hand, under the action of the pulse voltage, the current flowing in a spiral forms a magnetic field perpendicular to the surface of the chip. Due to magnetic field The intensity is proportional to the intensity of the current surrounding the area, so the closer the field is to the center, the stronger it is. The electrons are subjected to a centripetal force under the action of a magnetic field, and the closer the centripetal force is to the middle, the smaller the radius of the electron spiral motion, thereby increasing the current density in the middle portion.

Its radius of gyration is:

r=m v sinθ/eB

Where m is the electron mass, v is the electron velocity, θ is the emission angle, e is the electron charge, and B is the magnetic induction.

Rotation increases the trajectory of the electrons, so that the total ionization effect is enhanced, and the interface of the dielectric is dissolved into the electrode grain boundary layer at a smaller angle, which changes the original vertical movement of the electrons to the grain boundary, so that The electrode surface is easily damaged, and the probability of damage to the electrode crystal interface of the entire chip is also lowered, forming a highly efficient low temperature mode. The existence of the spiral structure electrode enables the electron induction accelerator to provide energy: under the action of the alternating electromagnetic field, the magnetic field whose magnetic field changes when the spiral-shaped electrode flows through the current acts to accelerate and focus the electron rotation, causing a change. Induced electromotive force, the induced electromotive force increases the horizontal movement speed of the electrons. As a whole, the electron energy is higher than that of the simple voltage, and it is easier to cross the semiconductor barrier, thereby generating a larger flow rate and the speed at which the carriers pass through the barrier. Faster and shorter time.

As a result of the inward rotation of the electrons, the number of electrons passing through the middle increases, which weakens the effect of the high-frequency current skin effect. The effective cross-sectional area of the current through the chip increases, the pressure-sensitive resistance decreases, and the energy consumed decreases. The resistance of the sensitive resistor is enhanced.

2, thermal performance:

In addition to the uniform distribution of current, a curved conductor can improve its tensile strength, heat dissipation of the conductor and uniformity of current density distribution, and greatly benefit the stability of the conductor device under cyclic loading. At the office. The current is evenly distributed on the chip electrode, the surface temperature is also lowered, the specific heat capacity and thermal conductivity are improved, the uniform distribution of the metal lead and the effective area are increased, and the heat absorption by the core is effective. Greatly enhanced, and the ability to dissipate heat is also a uniform increase in overall enhancement of specific heat.

At the same time, since the current flowing through the chip is more uniform, the temperature gradient on the chip is reduced, and the risk of damage caused by the difference in thermal expansion is also reduced. The spiral lead not only increases the heat-sensitive heat-dissipating area, but also makes the heat-dissipating part more uniform, thereby improving the thermal characteristics of the varistor.

The tensile strength of the linear "L" electrode structure of the metal wire is poor. The thermal expansion and contraction deformation of the metal wire at high temperature and the inconsistency of the expansion coefficient of the dielectric in contact with each other. The metal wire will "pull" the dense silver layer of the electrode. Silver surface damage caused by the surface It is known that curved conductors in material mechanics can improve their tensile strength. Due to the improvement of the tensile strength and the uniformity of the current density of the spiral metal electrode, the thermal expansion and contraction effect greatly reduces the "pull" destructive force of the dense silver surface of the electrode of the chip body, and the complete impact resistance of the electrode silver layer The anti-aging leakage current has a fundamental improvement, and the early failure phenomenon will be significantly reduced.

3. Flow improvement and crystal damage:

From the perspective of the internal crystal grains of the ceramic crystal, in addition to being subjected to the longitudinal electric field, it is also affected by the longitudinal magnetic field caused by the spiral lead. A longitudinally varying magnetic field produces an induced electromotive force in the horizontal direction, which in turn causes a decrease in the horizontal barrier height. Carriers are more likely to move between grains. According to the short plate theory of the bucket, the chip's ability to flow is stronger. The concept of P region and N region of an ideal semiconductor is used for identification. When the forward voltage is applied to the P region, the depletion layer is narrowed and the barrier height is lowered. Due to the increase in the area of the entrance and exit of the grain, the probability that the current concentrates at a certain position causes a grain boundary damage to decrease.

4, response time:

During charging the varistor,

Let the impedance encountered by conventional pressure-sensitive charging to the pressure-sensitive surface be R1, and the screw pressure sensitivity is R2.

then

1/R1=1/Rab+1/Rag

1/R2=1/Rab+1/Rag+1/Rbc+1/(ωLbc)

Expressed by the conductance G, that is

G1=Gab+Gag

G2=Gab+Gag+Gbc+1/(ωLbc)

Obviously,

R2<R1 or G2>G1

And the time required to charge Cmov through resistor R

T=∫dQ/I=∫Cmov*dV/(V/R)=R∫Cmov*dV/V

and so

Conventional pressure sensitive charging time: T1=R1*∫Cmov*dV/V

Spiral lead pressure sensitive charging time T2=R2*∫Cmov*dV/V

So there is

T2<T1

T2/T1=R2/R1

=1/[1/Rab+1/Rag+1/Rbc+1/(ωLbc)]*[1/Rab+1/Rag]

=1/[1+(Gbc+1/(ωLbc))/(Gab+Gag)]

That is to say, the time required for the spiral lead varistor to charge to the pressure sensitive turn-on voltage is smaller than that of the L lead varistor.

In summary, the present invention not only improves the resistance and flow capacity of the varistor under the power frequency voltage and the transient voltage, but also reduces the response time of the varistor, and also improves the thermal characteristics of the device. .

Claims

A spiral magnetic electrode package omnipotent pulse technology, which is characterized in that: the electrode is arranged on the body of the electronic component, and the electrode has a spiral shape. When the electrode is energized, the vertical axial magnetic field can restrain the electron, so that the original The linear trajectory of the electron becomes the trajectory of the spiral advancement. The action of the magnetic field causes the movement of the electron to become a spiral motion around the magnetic field line in the axial direction. The spiral structure of the metal wire forms a uniform electromagnetic field under the energization condition, and the electromagnetic wave is volume-type from the inside to the inside. The principle of external heating heats the entire electronic component.
The helical magnetic electrode package all-round pulse technology according to claim 1, wherein the electronic component body is in the form of a sheet, and the spiral-shaped electrodes are fixedly disposed on both sides of the chip body.
The helical magnetic electrode package all-round pulse technique according to claim 2, wherein the spiral-shaped electrode adopts a plane equiangular spiral or a planar constant velocity spiral.
The helical magnetic electrode package all-round pulse technology according to claim 1, wherein the electronic component body has a columnar shape, and the spiral wire electrodes are fixedly disposed at two ends of the chip body.
The helical magnetic electrode package omnipotent pulse technique according to claim 4, wherein the spiral-shaped electrode adopts a double helix without a broken end.
The spiral magnetic electrode package all-round pulse technology according to claim 1, wherein the electronic component body is provided with a silver coating layer, and the spiral wire electrode is fixedly disposed on the silver coating layer.
The spiral magnetic electrode package all-round pulse technology according to claim 6, wherein the spiral-shaped electrode is disposed on the high-conductivity layer by soldering, and the high-conductivity layer is a silver-coated layer or a conductive adhesive layer or super Conductive material layer.
The helical magnetic electrode package all-round pulse technique according to claim 1, wherein the spiral-shaped electrode is embedded in the electronic component body.
The spiral magnetic electrode package all-round pulse technology according to any one of claims 1 to 8, wherein the spiral-shaped electrodes on both sides of the electronic component body rotate in the same direction. Or rotate in different directions.
The spiral magnetic electrode package all-round pulse technique according to any one of claims 1 to 8, characterized in that the spiral-shaped electrode is a hollow metal spiral wire or a flat metal spiral wire.