JP6849167B2 - Electrostatic discharge protection composition and electrostatic discharge protection element using the composition - Google Patents

Description

The present invention relates to an electrostatic discharge protection composition and an electrostatic discharge protection element using the composition.

As the demand for portable electronic products increases and the types of electronic products used in various environments increase, the need for electrostatic discharge protection elements (Electrostatic discharges, ESD) to protect these electronic products increases. There is.

The need for such electrostatic discharge protection elements is further increasing as electronic products become smaller, more integrated, and faster.

As such an electrostatic discharge protection element, a TVS (Transient Voltage Suppressor) diode, an MLV (Multivarier varistor), a variable voltage polymer (Voltage Voltage polymer), or the like is used depending on the characteristics of an electronic product.

The TVS (transient voltage support) diode forms a PNP junction using p-type (p-type) and n-type (n-type) silicon elements, and measures against electrostatic discharge operate at a low voltage. It has the feature that it can respond quickly.

The above-mentioned MLV (multilayer variant) is an element that maintains insulation at a low voltage by sintering semi-conducting ZnO particles together with an inorganic additive, but is energized at a high voltage such as electrostatic discharge. Is.

The variable voltage polymer has a function of being energized only at a high voltage such as static electricity by putting a metal filler that conducts electricity in a polymer matrix (matrix).

Since the polymer composite has a capacitance of 1 pF or less, it is advantageous for application of a high-speed element and has an advantage that the manufacturing cost is low.

However, there is a problem that the durability of the electrostatic discharge protection element in the form of such a useful polymer composite is weakened, and as the user's product carrying time increases, the problem of durability against electrostatic discharge occurs. Is getting bigger.

In addition, since the case of the smartphone is made of a metal material, the problem that electric shock may occur due to the charging adapter has been continuously raised.

That is, if a voltage of 220 V at 60 Hz, which is supplied via an adapter during charging, is applied from the circuit board in connection with a case made of a metal material, an electric shock may occur when a person grips the case.

A solution to the problem of electric shock has been continuously proposed.

At this time, if the TVS diode element is used for electrostatic discharge, although electrostatic discharge is prevented, there may be a problem of being exposed to electric shock because the operating voltage is low.

In addition, the problems of electric shock and electrostatic discharge protection will be inconsistent in small electronic devices in which metal cases are used.

That is, if an element insulated from the case is introduced to prevent electric shock, the element inside the case will be damaged by electrostatic discharge, and if an element for electrostatic discharge protection is introduced, a person may get an electric shock. There is.

Korean Registered Patent No. 10-1392455 Korean Publication No. 2015-0066375 Korean Publication No. 2009-0104514

In order to solve the above problem, it is necessary that the operating voltage is sufficiently higher than the voltage at which electric shock occurs, and that the operating voltage for electrostatic discharge protection must not change significantly even if the number of exposures to electrostatic discharge increases. Sex occurs.

The above-mentioned TVS diode, capacitor, varistor, suppressor in the form of a polymer composite, and the like can provide both such an electric shock protection function and an electrostatic discharge protection function.

By the way, among these, the TVS diode is inferior in electric shock protection because the operating voltage of the electrostatic discharge protection function is low, and the capacitor has the electric shock protection function but is inferior in electrostatic discharge. Therefore, an element using a varistor or a polymer composite form is suitable for both electric shock and electrostatic discharge protection functions.

However, if both of the two materials are continuously exposed to electrostatic discharge, deterioration occurs inside the materials, and as a result of lowering the operating voltage, there is a high possibility that a short circuit will occur.

Therefore, even if the number of times static electricity is applied increases, the operating voltage must be maintained within a certain range.

An object of the present invention is to prevent deterioration of the material from occurring inside the material and lowering the operating voltage even when continuously exposed to static electricity discharge, so that even if the number of times static electricity is applied increases. It is an object of the present invention to provide an electrostatic discharge protection composition in which an operating voltage is maintained to a certain range, and an electrostatic discharge protection element using the composition.

According to one aspect of the present invention, there is provided an electrostatic discharge protection composition containing organic silicon, a plurality of metal powders, and porous silica particles capable of supporting a silicon component.

According to another aspect of the present invention, the base substrate, the first and second electrodes arranged apart from each other on the base substrate, and the first and second electrodes so as to integrally cover a part of the electrodes. The second electrode and an organic insulating layer formed on the base substrate and having a cavity arranged between the first and second electrodes are included, and the cavity is made of organic silicon. Provided is an electrostatic discharge protection element containing the metal powder of the above and a plurality of porous silica particles on which silicon is supported.

According to one embodiment of the present invention, the porous silica particles on which a silicon component is supported minimizes damage due to electrostatic discharge in the paste and reduces component changes, so that when applied to an electrostatic discharge protection element. The durability of the cavity can be improved.

It is a perspective view which shows the electrostatic discharge protection element by one Embodiment of this invention. It is sectional drawing of the electrostatic discharge protection element taken along the line I-I of FIG. It is a schematic diagram which shows the A region of FIG. 2 enlarged. It is an SEM photograph which showed that the inside of the cavity part was damaged in the conventional electrostatic discharge protection element. 6 is an SEM photograph showing damage to a cavity after applying static electricity using an electrostatic discharge gun in an electrostatic discharge protection element using porous silica particles according to an embodiment of the present invention. 6 is an SEM photograph showing damage to a cavity after applying static electricity using an electrostatic discharge gun in an electrostatic discharge protection element having a conventional composition.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention can be transformed into various other embodiments, and the scope of the invention is not limited to the embodiments described below. Also, embodiments of the present invention are provided to more fully explain the present invention to those having average knowledge in the art. Therefore, the shape and size of the elements in the drawings may be exaggerated for a clearer explanation.

When the directions are defined to clearly illustrate the embodiments of the present invention, D1 and D2 shown in FIG. 1 indicate the length direction and the width direction, respectively.

Hereinafter, an electrostatic discharge protection paste composition according to the present invention and an embodiment of an electrostatic discharge protection element using the same will be described in detail with reference to the accompanying drawings. In the description with reference to the attached drawings, the same or corresponding components are designated by the same drawing reference numerals, and duplicate description thereof will be omitted.

FIG. 1 is a perspective view showing an electrostatic discharge protection element according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the electrostatic discharge protection element taken along the line I-I of FIG.

Referring to FIGS. 1 and 2, the electrostatic discharge protection element 100 according to the present embodiment includes a base substrate 110, first and second electrodes 121 and 122, and an organic insulating layer 140.

The electrostatic discharge protection element 100 can further include a protective layer 160 and first and second external electrodes 151 and 152.

At this time, the electrostatic discharge protection element can be applied to an applied set or an electrostatic discharge suppressor component for protecting the IC component from static electricity. For example, a variable voltage polymer having inferior durability. It can be applied to a complex form of suppressor.

The base substrate 110 may be formed so as to support the first and second electrodes 121 and 122 and the organic insulating layer 140 laminated on the base substrate 110.

As shown in FIG. 1, the base substrate 110 can be formed in a plate shape.

However, the shape of the base substrate 110 is not limited to that shown in FIG. 1, and can be formed not only in a quadrangular shape but also in a circular plate shape or the like.

The base substrate 110 is made of an insulating material and can be insulated from the first and second electrodes 121 and 122 laminated on the base substrate 110.

Specifically, the base substrate 110 can be made of an insulating material so as to have an insulating property as a whole, and if necessary, the first and second electrodes 121 and 122 are laminated on one surface of the base substrate 110. An insulating film is formed and can be insulated from the first and second electrodes 121 and 122.

The insulating film formed on one surface of the base substrate 110 or the base substrate 110 can be made of an inorganic insulating material or an organic insulating material.

That is, the base substrate 110 may be, for example, a substrate made of an inorganic insulating material such as alumina or silica, or a substrate made of an organic insulating material such as an epoxy resin.

The first and second electrodes 121 and 122 are arranged on the base substrate 110 so as to be separated from each other.

The first and second electrodes 121 and 122 are arranged on the base substrate 110 so as to face each other at a predetermined separation distance.

At this time, the separation distance formed between the first and second electrodes 121 and 122 can be appropriately selected according to the required electrostatic discharge performance.

With reference to FIG. 2, the first and second electrodes 121 and 122 can be arranged so that their tip portions face each other.

Here, the tip ends of the first and second electrodes 121 and 122 mean one ends of the first and second electrodes 121 and 122 arranged in the inner region on the base substrate 110, and are on the base substrate 110. The other end of the first and second electrodes 121 and 122 arranged in the outer region is defined as the rear end.

The tip ends of the first and second electrodes 121 and 122 face each other, and the rear ends of the first and second electrodes 121 and 122 are connected to the first and second external electrodes 151 and 152, which will be described later, respectively. As such, it can be arranged parallel to the side surface of the base substrate 110 and exposed to the outside of the base substrate 110.

In the present embodiment, since the tips of the first and second electrodes 121 and 122 are separated by a predetermined distance, the voltage applied to both ends of the first and second electrodes 121 and 122 is equal to or less than a predetermined value. In some cases, no current flows.

However, when a voltage equal to or higher than a predetermined voltage, that is, an operating voltage is applied to both ends of the first and second electrodes 121 and 122, current flows even if the first and second electrodes 121 and 122 are separated from each other. There is.

Therefore, the separation distances of the first and second electrodes 121 and 122 can be changed depending on the set operating voltage value.

With reference to FIG. 1, the base substrate 110 can have a length direction D1 and a width direction D2 that are cross-formed with each other. The first and second electrodes 121 and 122 can be arranged apart from each other in the length direction D1 of the base substrate 110, and can be arranged in the central region of the base substrate 110 in the width direction D2 of the base substrate 110.

As shown in FIG. 1, the first and second electrodes 121 and 122 are formed to be narrower than the width of the base substrate 110, and are arranged on the base substrate 110 so as to cover only a part of the base substrate 110. be able to.

The organic insulating layer 140 is formed by being laminated on the first and second electrodes 121 and 122 and the base substrate 110 so as to integrally cover a part of the first and second electrodes 121 and 122, respectively.

Since the organic insulating layer 140 is formed so as to integrally cover a part of the first and second electrodes 121 and 122, respectively, the organic insulating layer 140 includes a separation space formed between the first and second electrodes 121 and 122. A part of the first and second electrodes 121 and 122, that is, a region adjacent to the tips of the first and second electrodes 121 and 122 can be integrally covered.

As shown in FIG. 1, the organic insulating layer 140 is not covered by the first and second electrodes 121 and 122 on one surface of the base substrate 110 on which the first and second electrodes 121 and 122 are arranged. It can be formed so as to cover the remaining region of the base substrate 110 arranged in the width direction D2 of the base substrate 110.

That is, the organic insulating layer 140 can have a width corresponding to the width of the base substrate 110.

Inside the organic insulating layer 140, a cavity 130 arranged between the first and second electrodes 121 and 122 is formed.

The cavity 130 formed inside the organic insulating layer 140 can be arranged between the first and second electrodes 121 and 122. When a voltage equal to or higher than the operating voltage is applied to the first and second electrodes 121 and 122, a current can flow between the first and second electrodes 121 and 122 through the cavity 130.

When a voltage in the form of a pulse such as static electricity is applied and a current flows between the first and second electrodes 121 and 122, the current flows through the organic insulating layer 140 covering the first and second electrodes 121 and 122. The organic insulating layer 140 may be damaged by the heat generated by the current flowing inside.

If the organic insulating layer 140 covering the first and second electrodes 121 and 122 is damaged for the above reasons, the durability of repeated use is significantly reduced, and the design value determined according to the required discharge performance can be changed. Therefore, even if an operating voltage is applied, no current can flow between both electrodes, or a current can flow at a voltage value equal to or lower than the operating voltage.

When the cavity 130 is formed inside the organic insulating layer 140 as in the present embodiment, the current can flow through the cavity 130, so that damage to the organic insulating layer 140 can be prevented and the element can be prevented. The overall durability of the device and the operating reliability of the device can be improved.

On the other hand, when the insulating layer covering the first and second electrodes 121 and 122 is made of an organic insulating material as in the present embodiment, the dielectric constant is lower than that when the insulating layer is formed of the inorganic insulating material, so that the electric capacity ( The Capacitance) value becomes smaller, which reduces interference in high-speed signals and improves discharge performance.

Further, also in terms of the manufacturing process, it is possible to form the insulating layer at a lower temperature by forming the insulating layer with the organic insulating layer, so that an economical advantage can be ensured.

With reference to FIG. 2, the first and second electrodes 121, 122 can be arranged so as to be exposed in the cavity 130.

By exposing the tips of the first and second electrodes 121 and 122 into the cavity 130, the current flowing between the first and second electrodes 121 and 122 does not pass through the organic insulating layer 140 but is exposed in the cavity 130. Can flow through.

FIG. 3 is a schematic view showing an enlarged region A in FIG.

Referring to FIG. 3, the cavity 130 comprises an electrostatic protection paste composition comprising organic silicon 131, a plurality of metal powders 132, and porous silica particles 134 capable of supporting the silicon component 133 as a medium. ..

In the static electricity protection paste composition of the present embodiment, the metal powder can be uniformly or non-uniformly dispersed in the organic silicon. As a result, the cavity 130 can function as an auxiliary electrode.

At this time, the metal powder is preferably nickel nanoparticles or aluminum particles.

Here, the aluminum particles can be particles having an average particle diameter of 3 μm or less based on the diameter D50.

If the diameter of the aluminum particles is excessively large relative to the distance between the electrodes facing each other, the aluminum particles can come into direct contact with at least one of the two opposing electrodes.

In order to prevent such a phenomenon, the average particle size of the particles with respect to the distance between the electrodes is limited. Preferably, the average particle size of the aluminum particles relative to the spacing between the electrodes can have a value of 1/5 to 1/3.

Normally, when the distance between the electrodes is about 20 μm, the average particle size of the aluminum particles in this embodiment can be 3 μm or less.

The nickel nanoparticles of the present embodiment preferably have an average particle size of 500 nm or less based on the diameter D50.

Like the aluminum particles, the nickel nanoparticles can also have a limited average particle size. In the case of nickel nanoparticles, as the size increases, the shape becomes more spike-shaped than spherical, so that the average particle size is limited to 500 nm as a preferable size for obtaining spherical particles.

At this time, when the metal powder is nickel nanoparticles, the cavity can contain 20 to 35% by weight of organic silicon, 60 to 75% by weight of nickel nanoparticles, and 5 to 10% by weight of porous silica particles.

When the content of the organic silicon is less than 20% by weight, the distance between the particles becomes too close to maintain insulation, and shorts occur due to contact between nickel nanoparticles which are metal-filled particles. There is a fear. Further, when the content of the organic silicon exceeds 35% by weight, the distance between the particles becomes too long, and there is a possibility that a problem may occur in which an electric current cannot be passed even when static electricity is applied.

In a similar logic, when the content of metal powder, the content of organic silicon, and the content of porous silica particles satisfy 100% by weight, when the content of organic silicon decreases, the nickel nanoparticles or porous silica particles The content will be relatively high.

Therefore, when the content of the porous silica particles is less than 5% by weight, the amount of organic silicon contained therein may be small and the durability may not be improved. Further, when the content of the porous silica particles exceeds 10% by weight, the insulating property becomes too large and may act as a factor that hinders the passage of electric current when static electricity is applied.

When the metal powder is aluminum particles, the cavity can contain 20-35% by weight of organic silicon, 50-65% by weight of aluminum particles, and 5-10% by weight of porous silica particles.

Since the same action and critical significance as those of the nickel nanoparticles described above are applied to the aluminum particles, detailed description thereof will be omitted in order to avoid duplication.

Further, the porous silica particles can improve the durability against electrostatic discharge impact by supporting a silicon component which is a medium selected as an organic binder.

Usually, the polymer composite is formed by filling conductive particles in an insulating material such as organic silicon. By printing between two opposing external electrodes using the composition thus produced, an element in the form of a suppressor can be manufactured.

When static electricity is applied to the element manufactured in this way, the paste component deteriorates inside the element. For most polymer composites, the polymer components, which are relatively sensitive to electrostatic and thermal behavior, will deteriorate.

That is, in the conventional cavity, an empty space is created inside when static electricity is applied, and an agglutination phenomenon of the added filler occurs. As a result, there is a tendency for the silicon component to gradually decrease in this agglomerated space.

FIG. 4 is an SEM photograph showing that damage has occurred inside the cavity in the conventional electrostatic discharge protection element. As shown in FIG. 4, it can be seen that as the number of electrostatic discharges increases, cavities are formed inside, and at the same time, the components of specific substances as internal components relatively decrease.

That is, it can be seen that more metal components are aggregated and relatively less silicon components are distributed.

In the polymer form, it is the organic silicon component that maintains the insulation, but as this component decreases, the insulation performance gradually deteriorates.

This can also be confirmed from the change in operating voltage.

Such fracture is not only a phenomenon that occurs only in the polymer composite form, but also a phenomenon that occurs in the varistor form.

It turns out that the energy released by the electrostatic discharge is so concentrated and very destructive.

In the above varistor material, in order to further improve the durability and minimize the destruction before and after the application of static electricity, the surface of the conductive particles is coated with a vitreous component, so that the material is more destroyed even when the static electricity is applied. A direction to strengthen the functional layer has been proposed for a structure that does not occur.

That is, a method is used in which the surface of conductive particles is coated with an inorganic insulating substance so that destruction or deterioration does not occur even when an impact is applied by static electricity.

Alternatively, in order to prevent changes in the applied electrode, the electrode may be coated with a metal having a high melting point such as tungsten or nickel.

However, the technology for such weakening durability has not yet been completely introduced.

In the present embodiment, when the porous silica particles are added to the cavity 130, the organic silicon component is confined inside the pores of the porous silica particles, and the pores are destroyed when an impact due to static electricity is applied. Then, the organic silicon component passes through, and the action of filling the destroyed portion occurs.

Therefore, the porous silica particles reduce the phenomenon that the organic silicon component is reduced in space due to the aggregation of the conventional filler, and as a result, the durability of the electrostatic discharge protection paste is improved.

Therefore, as shown in FIGS. 5 and 6, in the case of the present embodiment, even if damage (damage) inside the cavity occurs, the region is remarkably narrow as compared with the electrostatic discharge protection element having a conventional composition. You can confirm that.

On the other hand, the organic insulating layer 140 can be made of a material containing at least one of epoxy, polyurethane, and silicon.

That is, the organic insulating layer 140 can be made of an organic insulating material such as a polymer resin, and since such a material has a lower dielectric constant than an inorganic insulating material, interference in a high-speed signal is small and is generally high. Discharge performance can be maintained.

Further, referring to FIGS. 1 and 2, the electrostatic discharge protection element 100 according to the present embodiment can further include a protective layer 160 and first and second external electrodes 151 and 152.

The protective layer 160 is placed on the first and second electrodes 121, 122, the organic insulating layer 140, and the base substrate 110 so as to cover the first and second electrodes 121 and 122, the organic insulating layer 140, and the base substrate 110. It can be formed by stacking.

At this time, the protective layer 160 is made of a material containing an epoxy resin, and can be electrically insulated from the first and second electrodes 121 and 122 in the same manner as the base substrate 110.

The protective layer 160 can integrally cover the remaining region of the base substrate 110, the first and second electrodes 121 and 122, and the upper and side surfaces of the insulating layer 140, which are not covered by the organic insulating layer 140.

The base substrate 110 can serve to support the pair of electrodes 121 and 122 and the organic insulating layer 140, and the protective layer 160 is the upper surface of the base substrate 110, the first and second electrodes 121 and 122, and the organic insulating layer. All 140 can be covered to protect each configuration at the same time.

The first and second external electrodes 151 and 152 are electrically connected to the rear ends of the first and second electrodes 121 and 122, respectively, and are arranged so as to cover the side surfaces of the base substrate 110 and the protective layer 160. To.

Therefore, a power source can be applied to the first and second external electrodes 151 and 152, which are electrically connected to the first and second external electrodes 151 and 152, respectively, and arranged on the base substrate 110. It can be transmitted to the first and second electrodes 121 and 122.

Hereinafter, a paste composition for protecting static electricity will be produced according to Examples and Comparative Examples of the present invention, and the durability of the paste composition will be compared.

In Example 1, the metal powder of the paste composition is metallic nickel nanoparticles, 9 g of nickel nanoparticles (300 nm), 1 g of porous silica particles, and 3 g of organic silicon (manufactured by Shinetsu Chemical Industry Co., Ltd., KE1842). Was mixed and stirred.

The mixture was dispersed using a 3-roll mill. At this time, in the 3-roll mill (EXAKT, 80E), the distance between the rolls is set to 10 μm and passed four times (pass), and then the distance between the rolls is set to 5 μm and passed twice. , Revolution 900, Rotation 700, time 1 min) After completion of dispersion by mixing, the viscosity and film density of the paste composition were measured.

Then, the paste composition of Example 1 was passively printed on a test coupon (interval 50 μm, width 150 μm), dried at 100 ° C. for 10 minutes, and then heat-cured at 175 ° C. for 1 hour and 30 minutes.

After thermosetting, the sample was cooled to room temperature, and then the resistance was measured using a multimeter. From this measured resistance, it was confirmed whether the printed paste composition was insulated.

After that, static electricity was applied at 8 kV level 4 (IEC6100-4-2) using an ESD gun, and the leakage current (leakage current) was measured at 5 V DC to confirm the durability of the antistatic paste composition. did.

In Example 2, the metal powder of the paste composition is aluminum particles, and 9 g of aluminum particles (D50, 3 μm), 1 g of porous silica particles, and 3 g of organic silicon (KE1842, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) are used. It is mixed and stirred. Using this mixture, a paste composition was produced and evaluated in the same manner as in Example 1.

A comparative example is a paste composition obtained by removing porous silica particles, in which 10 g of nickel nanoparticles (300 nm) and 3 g of organic silicon (KE1842, manufactured by Shin-Etsu Chemical Co., Ltd.) are mixed and stirred. Is. Using this mixture, a paste composition was produced and evaluated in the same manner as in Example 1.

As a result of producing and evaluating the paste compositions according to Examples 1 and 2 and Comparative Examples as described above, the ESD durability of Examples 1 and 2 was achieved 1000 times, but the comparative example was 200 times. It was confirmed that the leakage current increased in the vicinity.

Here, the increase in the leakage current means that the current flows through the organic insulating layer 140. That is, the insulation is not stably maintained after the static electricity is applied, and the current flows continuously at the 5V DC voltage. In this case, if the connected terminal is the battery part, the charged electricity. Energy leakage occurs, resulting in signal attenuation in the case of IC circuits operating at 5V.

Therefore, it can be said that the insulation is maintained immediately after the application of static electricity, the leakage current is reduced, and there is no abnormality in the performance of the SET product. In the case of Examples 1 and 2 above, such reliability can be satisfied.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited to this, and various modifications and modifications are made within the scope of the technical idea of the present invention described in the claims. It is clear to those with ordinary knowledge in the art that this is possible.

100 Electrostatic discharge protection element 110 Base substrate 121, 122 1st and 2nd electrodes 130 Cavity 131 Organic silicon 132 Metal powder 133 Silicon component 134 Porous silica particles 140 Insulation layer 151, 152 1st and 2nd external electrodes 160 Protective layer

Claims (6)

With the base board
The first and second electrodes arranged apart from each other on the base substrate,
An organic substance formed on the first and second electrodes and the base substrate so as to integrally cover a part of the electrodes and having a cavity internally arranged between the first and second electrodes. Insulation layer and
Grooves are provided on both end faces, and the ends of the first and second electrodes are exposed on the organic insulating layer and the base substrate through the grooves, and both end faces are both ends of the base substrate. A protective layer that forms one surface with each surface,
The base substrate and both end faces of the protective layer include first and second external electrodes arranged so as to be connected to the exposed ends of the first and second electrodes, respectively.
The cavity contains organic silicon, a plurality of metal powders, and a plurality of porous silica particles in which an organic silicon component is supported inside a pore.
The metal powder is an aluminum particle, and an electrostatic discharge protection element having an average particle size of 3 μm or less. The electrostatic discharge protection element according to claim 1 , wherein the cavity includes 20 to 35% by weight of the organic silicon, 50 to 65% by weight of the aluminum particles, and 5 to 10% by weight of the porous silica particles. The electrostatic discharge protection element according to claim 1 or 2 , wherein the first and second electrodes are arranged so as to be exposed in the cavity. The electrostatic discharge protection element according to any one of claims 1 to 3 , wherein the organic insulating layer contains at least one of epoxy, polyurethane, and silicon. The protective layer, the electrode, the organic insulating layer, and to cover the base substrate, the first and second electrodes, said organic insulating layer, and is formed on the base substrate, of claims 1-4 The electrostatic discharge protection element according to any one of the above items. Said first and second external electrodes, said first and second electrodes and are electrically connected respectively, wherein is arranged so that the base substrate and covers the side surface of the protective layer, electrostatic discharge according to claim 5 Protective element.

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