JPH0982453A - Chip-form electrostatic protection element and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a discharge gap with accurate dimension and construct small and at a low cost by applying a plating to the end face of a land exposed at the top and bottom surfaces of an insulative gap layer so that the resultant discharge gap is formed protrusively. SOLUTION: A copper foil is attached by hot press to each surface of an insulative film, and the area where no copper foil is required is removed by etching so that gap forming lands 202 and wiring parts 203 for a pair of electrostatic protection elements are formed. Therein a plurality of protection element wiring parts are arranged in series in the longitudinal direction in such an arrangement as pinching a terminal for end face connection and in the crosswise direction parallel lines are formed continuously. Holes 3 having a specified diameter are provided, and each hole is furnished with a protrusion owing to a thickened copper plating so that the shortest distance 5-150μm is produced at the end face of the gap forming land 202 exposed at the inner wall. This heightens the accuracy of the discharge gap, provide precise controllability for the discharge voltage, allows manufacturing simply at a low cost, and produces stable characteristics through electric discharging at the protruded part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic resin chip-type electrostatic protection element having a discharge gap and a method for manufacturing the same.

[0002]

2. Description of the Related Art An electrostatic protection element is used for electrostatic protection of electronic equipment, and is usually connected in parallel with an IC or LSI element to be protected from static electricity, and in a normal state (when there is no electrostatic pulse). , It is in an insulating state and does not affect the circuit, but only when an electrostatic pulse is applied (S1 in FIG. 5 is on), the protection element becomes conductive and elements such as IC and LSI are protected from electrostatic damage. To protect. 2. Description of the Related Art Conventionally, elements that protect ICs and LSIs from static electricity include varistor, Zener diode, and discharge gap element, which are properly used depending on the application. In the case of a varistor or a Zener diode, the leakage current is large, and in the case of a Zener diode, since it has a polarity, it can be used for either positive charge or negative charge, and it applies to both positive and negative. In order to
Since it is necessary to face each zener diode, there is a problem that the cost becomes high. On the other hand, the discharge type element has a small leakage current and is simple in principle,
It has the advantage that it is hard to break down. The discharge voltage is
It is determined by adjusting the discharge gap, and further, when the discharge gap has a sealing structure, by changing the gas pressure and the gas type.

As an element which is actually commercially available, there is one in which a conductor coating is formed on the surface of a cylindrical ceramic, a discharge gap is provided in the coating by a laser or the like, and this is sealed with glass. Protectors (trade name, manufactured by Mitsubishi Materials Corporation) and the like are known. Further, as a method for directly forming a discharge gap on a wiring board, Japanese Patent Laid-Open Nos. 2-223182, 3-895588, 3-261086, and 4-22086 are known. Japanese Patent Laid-Open No. 5-678
It is known from, for example, Japanese Patent Publication No. 51.

[0004]

A commercially available glass-sealed tube discharge gap type element has extremely excellent characteristics, but its shape is complicated, so that a small surface mounting element (hereinafter referred to as a chip). ) Size, eg 1-2 mm
It is difficult to reduce the width, the length of 2 to 4 mm, and the thickness of 1 to 2 mm, and it is expected that it is difficult to reduce the cost because there are many kinds of constituent materials.

On the other hand, JP-A-2-223182, JP-A-3-89588, JP-A-3-261086, JP-A-4-22086, and JP-A-5-678.
The method disclosed in Japanese Patent No. 51, etc. is basically a method of forming a discharge gap on a substrate. However, in the usual method, the gap distance of the discharge gap that can be formed is 15
It is 0 μm or more, and its forming accuracy is plus or minus 20 to 30 μm. Actually Japanese Patent Laid-Open No. 2-2
No. 23182, several mm, Japanese Patent Application Laid-Open No. 3-89588, 4 mm, Japanese Patent Application Laid-Open No. 3-261086, 0.5 mm.
mm, in Japanese Patent Laid-Open No. 5-67851, 0.15 mm is exemplified as the distance of the discharge gap. In the gap of these values, the discharge voltage is high, the protection effect is limited, and it is not suitable for protection of static sensitive IC or LSI.
That is, the relationship between the discharge voltage between the parallel electrodes and the gap is
Shizuka "Electrostatic Handbook", page 221 (edited by The Institute of Electrical Engineers of Japan, Showa 6)
As shown in FIG. 4, which is drawn from the formula of Ohmsha, Inc. on June 20, 2013, the minimum gap that can be created by the conventional technique is 0.15 mm, but the discharge voltage between parallel electrodes is
It reaches about 1.5kV. When using a protruding electrode, 1
Although the discharge voltage drops by about 20%, it cannot be used to protect ICs or LSIs with low power supply voltage.
The gap formation accuracy is low.

Further, none of the above-mentioned publications discloses protection of the discharge gap portion from the use environment, but without this protection, because of humidity and gas in the environment,
It is expected that the discharge voltage will change due to contamination of the conductor surface. Therefore, if the normal resists are directly coated for protection, the resists are filled in the discharge gap portion, and the discharge voltage greatly increases, which is not practical. Further, even if a very small gap capable of obtaining electrostatic protection can be formed in a state where the resists are filled (when the resists are filled, unless the gap gap is set to 1 to 2 μm or less, a protective effect is obtained). However, if discharge occurs in such a state, the resists filled in the discharge gap will be slightly deteriorated, resulting in a decrease in insulation resistance and, in some cases, conduction. There is a problem that occurs.

It is an object of the present invention to provide a chip-type electrostatic protection element which is excellent in accuracy, can be miniaturized, and can be manufactured at low cost in a discharge gap type electrostatic protection element, and a manufacturing method thereof.

[0008]

A chip type electrostatic protection device according to the present invention comprises two terminal portions 201, a pair of discharge gap forming lands 202, and a wiring connecting the terminal portions 201 and the discharge gap forming lands 202. A gap layer 101 composed of a portion 203 and an insulating layer 1 supporting them, the insulating layer 1 being interposed between two discharge gap forming lands 202, the pair of discharge gap forming lands 202 and a terminal portion. 201 and wiring section 203
And at least three insulating layers of a protective layer 102 for protecting both sides of the gap forming land 202.
Has an exposed hole 3, and the gap forming land 202 projects from the inner wall of the hole 3.

A method of manufacturing such a chip-type electrostatic protection element is as follows. A step of making holes 3 in the double-sided copper-clad laminate, b. A step of manufacturing a substrate having a pair of discharge gap forming lands 202 and a wiring portion 203 by selectively removing the conductor layers on both sides by etching, c. On both surfaces of this substrate, an insulating material to be the protective layer 102,
A step of laminating and adhering the metal foil 401 to the outside thereof, d. A step of forming a through hole 4 so as to cut the wiring portion 203 at a place of the wiring portion 203 of this laminated adhesive, e. The entire surface of the metal foil 401 and the inner wall of the through hole 4,
Conducting step, f. The terminal portion 201 is provided around the through hole 4 with the metal foil 401.
Forming by selective etching removal of g. By cutting from the center of the through hole 4,
A step of cutting into individual chip type electrostatic protection elements, and between steps a and b, or between steps b and c,
The method is characterized by including the step of causing the discharge gap forming land 202 exposed on the inner wall of the hole (3) by plating to protrude from the inner wall surface of the hole 3.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the structure of the present invention, the shortest distance between the pair of discharge gap forming lands 202 becomes the discharge gap when an electrostatic pulse or the like is applied, and this distance is extremely important. The range is preferably 5 to 60 μm for protection of ordinary electronic elements. If the distance is less than 5 μm, it is difficult to control the accuracy of the distance and the manufacturing is difficult. Therefore, the protection voltage becomes high, and the electronic parts may be destroyed by the discharge. The thickness of the discharge gap layer can be set to 5 to 30 μm in order to protect ICs and LSIs that are more sensitive to static electricity, and especially in applications where only a large pulse voltage portion needs to be removed. , 150 μm or so.

The base material of the double-sided metal foil-clad laminate or the single-sided metal foil-clad laminate used in the present invention may be a film or a prepreg of a thermosoftening resin such as polytetrafluoroethylene, or a relative material. It is also possible to use an insulating material in which the surface of a resin material or a thermosetting insulating material having a high softening temperature is coated with a material having a low softening point. Polytetrafluoroethylene or a polyimide resin is used as the insulating material thus coated, and a resin material having a lower softening point than those of the adhesive layer is used, for example, tetrafluoroethylene / ethylene copolymer. By using such a material, the lamination adhesion temperature can be lowered and the thermal strain of the substrate can be reduced.

The conductor layer of the double-sided metal foil-clad laminate or the single-sided metal foil-clad laminate used in the present invention is selected from conductivity, corrosion resistance, easiness of wiring formation, and the like. And plating (vapor phase, liquid phase), and combinations thereof. From the viewpoints of the above-mentioned characteristics and subsequent processability, etc., ¥, copper, nickel, gold, silver, aluminum and the like are suitable, but not limited thereto. The thickness of this conductor layer may be a thickness sufficient to release static electricity that flows instantaneously, and mainly from the ease of manufacture and cost,
Thickness is decided. For vapor phase plating, around 1 μm,
If liquid plating or metal foil is used, 5 μm to 7 μm
Those of about 0 μm are suitable.

Of the constituent materials of the present invention, at least the material forming the discharge gap layer 101 is particularly desirable because the fluorine-based resin and the polyimide-based resin are less likely to deteriorate due to discharge. This fluororesin includes copolymers such as polytetrafluoroethylene, tetrafluoroethylene / hexafluoropropylene copolymer, tetrafluoroethylene / ethylene copolymer, and tetrafluoroethylene / perfluoroalkoxyethylene copolymer. ,
A modified resin obtained by modifying a fluorine-based resin with another organic resin can be used. From the price, polytetrafluoroethylene is cheap and suitable. Also, since the molding temperature is low,
Tetrafluoroethylene / perfluoroalkoxyethylene copolymer and even lower tetrafluoroethylene /
Ethylene copolymers are suitable. Further, in the case of a polyimide-based resin, it may be used alone, which has been subjected to modification or the like to impart adhesiveness, or provided with an adhesive layer, the adhesive layer is a resin material that is difficult to deteriorate, for example, Fluorine-based or polyimide-based resin may be used. These combinations and the like have various modes and are not limited. In the latter case, plasma treatment, corona treatment, or short-wavelength ultraviolet irradiation on the surface of the polyimide resin is effective for improving the adhesive strength with the adhesive.

The relationship between the thickness (z) of the gap layer 101, the discharge gap distance (x) determined by the target discharge voltage, and the thickness (y) of the plating applied to the wiring layer exposed on the inner wall is as follows. Is isotropically attached, z = x +
2y, and the thickness (z) of the base material and the thickness (y) of plating can be determined from the manufacturing cost, easiness of manufacturing, and the like. Note that, here, the plating is assumed to be isotropic, but even if it is not isotropic, the same calculation can be performed by knowing the extent thereof in advance.

Hole 3 of the gap forming land 202 of the present invention
The height of protrusion from the inner wall surface of is preferably in the range of 5 to 100 μm, and this range is derived from the aforementioned discharge characteristics, the thickness of each constituent material, and the above calculation formula.

In addition to the steps described above, the method of manufacturing the chip type electrostatic protection element of the present invention is the same as the steps a and b. By selectively removing the conductive layer of the double-sided metal foil-clad laminate by etching, a pair of discharge gap forming lands is formed.
A step of manufacturing a substrate having 202 and a wiring portion 203, i. A method including a step of laminating and adhering an insulating layer to be the protective layer 102 on both surfaces of this substrate and forming holes 3, or instead of steps a and b, j. The conductor layer is selectively etched and removed from one pair of the discharge gap forming lands 202 and the wiring portion 203 of the pair of discharge gap forming lands 202 and the wiring portion 203 on the two single-sided metal foil-clad laminates. A step of forming by k. A step of making a pair of discharge gap forming lands 202 face each other so as to face each other, interposing an insulating adhesive layer base material to be the gap layer 101 therebetween, and laminating and adhering the substrate, m. Making holes 3 in this substrate, n. There is a method including a step of plating the discharge gap forming land 202 exposed on the inner wall of the hole 3 of the substrate and projecting the wiring from the inner wall surface.

Insulation for forming the gap layer 101 exposed on the inner wall of the hole 3 and, in some cases, the protective layer 102 between the step of forming the hole 3 and the step of closing the hole 3 with the protective layer 102. A step of performing a smear treatment in which the layer is brought into contact with a solution capable of dissolving can be added, and the solution capable of dissolving the insulating layer is selected from concentrated sulfuric acid, permanganate-based solution, and chromic acid-based solution. Can be used.

In order to prevent the insulating material of the protective layer 102 to be subsequently laminated from flowing into the hole 3, it is preferable to use a low-flow insulating material as the insulating material of the protective layer 102. As such a low-flow insulating material, a thermosoftening resin material such as a fluororesin or a high molecular weight epoxy polymer can be used.

[0019]

According to the present invention, the discharge gap is formed by plating the end faces of the lands exposed from the upper and lower surfaces of the insulating gap layer so as to project, and the discharge gap interval can be formed with high accuracy. Is. In terms of discharge characteristics, air discharge occurs between the protruding platings, and deterioration of the base material surface due to discharge does not substantially occur.

Regarding protection from the environment, a space is formed around the discharge gap portion to form a structure in which the discharge portion is isolated from the outside, and environmental substances, such as water vapor and sulfurous acid, which have permeated from the cross section of the substrate. A small amount of gas, etc. will not enter and will not corrode the static electricity protection element wiring. Further, by using a fluorine-based resin or a polyimide-based resin for the base material in contact with the discharge gap portion, deterioration due to discharge is unlikely to occur, and the safety is higher than when a general resin is used for the discharge gap portion.

When the resin film having a low softening point of the present invention is inserted between the base material and the outer metal foil, the reinforcing material for maintaining the mechanical strength of the base material supporting the discharge gap pattern and the wiring portion. The use of a resin containing a resin is preferable because it can suppress the influence of diffusion of environmental substances from the interface of the reinforcing material.

Further, according to the present invention, since the electrostatic protection element wiring portion is housed in the insulating substrate, the structure is simple as compared with the conventional sealed tube type element. The target device can be manufactured at low cost.

[0023]

Example A copper foil having a thickness of 18 μm was laminated on both sides of an Aflex film (trade name, manufactured by Asahi Glass Co., Ltd.), which is a tetrafluoroethylene / ethylene copolymer, having a thickness of 100 μm, and pressing conditions were set. , Temperature 280
Thermocompression bonding was carried out at a temperature of 30 ° C. for 30 minutes at a pressure of 20 kg / cm ² . At this time, a glossy surface was used as an adhesive surface of the copper foil with the resin film (shown in FIG. 2A). An etching resist is formed on each of the copper foil surfaces, and unnecessary copper foil portions are selectively etched and removed by spraying a chemical etching solution containing a cupric chloride solution as a main component.
The discharge gap forming land 202 of the pair of electrostatic protection elements and the discharge gap forming land 202 and the wiring portion 203 of each set of the wiring portion 203 connected to the discharge gap forming land 202
Was formed (shown in FIGS. 2B to 2D). The pattern at this time has a shape in which a plurality of electrostatic protection element wiring parts are arranged in series in the vertical direction with the end-face connection terminals sandwiched between them, and one continuous array in the horizontal direction is arranged in parallel. did. Copper foil MC with high molecular weight epoxy polymer on both sides
F3000E (manufactured by Hitachi Chemical Co., Ltd., trade name) is overlaid, the press conditions are thermocompression bonding at a temperature of 170 ° C. for a time of 90 minutes at a pressure of 20 kg / cm ² , and then the above chemical etching liquid is sprayed on the surface. The copper foil of was removed (Fig. 2
(E). ). Although the copper foil MCF3000E with a high molecular weight epoxy polymer was used here, it is not always necessary to use an insulating material with a copper foil. Next, the hole 3 having a hole diameter of 1.2 mm is drilled (shown in FIG. 2F), and the discharge gap forming land 20 exposed on the inner wall of the hole 3 is formed.
Electroless thick copper plating was applied to the end face of 2 (Fig. 2
(G). ). At this time, the amount of copper plating and the thickness of the shortest distance between the protrusions are obtained in advance, and the shortest distance between the protrusions is 30.
A substrate having a thickness of μm and a substrate having a thickness of 50 μm were prepared. Copper foil MCF300 with high molecular weight epoxy polymer, which has low fluidity when heated at the time of bonding, on both surfaces of this substrate
0E (trade name, manufactured by Hitachi Chemical Co., Ltd.) was overlaid and thermocompression bonded under the same conditions as described above (shown in FIG. 2 (h)). Through holes are provided in this laminate (see FIG. 2).
Shown in (i). ), The inner wall of the through hole and the entire surface of the copper foil are further electroless plated to a thickness of 15 μm (shown in FIG. 2 (j)) to form the connection lands forming the terminal portion.
It was formed by selectively etching away the copper foil other than the periphery of this through hole (shown in FIG. 2 (k)).

The substrate on which the chip-type electrostatic protection element manufactured in the example was formed was cut into individual electrostatic protection element units, and the discharge voltage was measured and the IC protection effect was confirmed using the individual elements. The discharge voltage was measured with a DC voltage. Regarding the protection effect of the IC, using the circuit of FIG. 6, a pulse generator ESD8012 (manufactured by Sanki Denshi Kogyo Co., Ltd., trade name), voltage 10 kV, waveform IEC80
1-2 standardized electrostatic pulse, TTL7 SN7
10 pulses were continuously applied to the input terminal of 5189AN (trade name, manufactured by Texas Instruments Incorporated) at a pulse interval of 1 second, and then the operation of the IC was confirmed. As a result, the discharge voltage was 480-520 V (n = 5), 50 μm when the shortest distance between the protrusions was 30 μm.
It was 670-750V (n = 5). Further, in the case of the shortest distance of 30 μm or 50 μm, the IC operated normally after the IC protection effect test.

[0025]

As described above, according to the present invention, the accuracy of the discharge gap can be increased and the discharge voltage can be accurately controlled, and a chip type electrostatic protection element, and such an element can be simply and inexpensively manufactured. It is possible to provide a method that can be manufactured by. Further, according to the structure of the present invention,
Since discharge occurs at the protrusions, stable characteristics can be obtained.

[Brief description of drawings]

1A to 1L are views showing respective steps for explaining an embodiment of the present invention, respectively.
(D) and (g) to (k) are cross-sectional views, (e) and (f) are plan views showing wiring on the front and back surfaces of the substrate in step (d),
(L) is a plan view showing how to cut each element.

2 (a) to (k) are cross-sectional views showing respective steps for explaining another embodiment of the present invention.

3 (a) to 3 (g) are cross-sectional views in each step for explaining yet another embodiment of the present invention.

FIG. 4 is an external perspective view showing an embodiment of the present invention.

FIG. 5 is a diagram showing a relationship between a gap distance between parallel electrodes and a spark voltage for explaining the principle of the present invention.

FIG. 6 is a block diagram showing a measuring method for explaining the effect of the present invention.

[Explanation of symbols]

 120. Base material 130. Copper foil 140. End face connection pad 150. Electrostatic protection element wiring section 151. Plating 121. Base material 122. Base material 160. Holes for forming voids 161. Void 170. Etching resist 180. Holes for end face connection 181. End face connection terminal 182. Cutting line 190. Plating

[Procedure amendment]

[Submission date] September 19, 1995

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of drawings]

1A to 1L are views showing respective steps for explaining an embodiment of the present invention, respectively.
(D) and (g) to (k) are sectional views, (e) and (f) are plan views showing wiring on the front and back surfaces of the substrate in step (d),
(L) is a plan view showing how to cut each element.

2 (a) to (k) are cross-sectional views showing respective steps for explaining another embodiment of the present invention.

FIG. 3 is an external perspective view showing an embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a gap distance between parallel electrodes and a spark voltage for explaining the principle of the present invention.

FIG. 5 is a block diagram showing a measuring method for explaining the effect of the present invention.

[Explanation of Codes] 120. Base material 130. Copper foil 140. End face connection pad 150. Electrostatic protection element wiring section 151. Plating 121. Base material 160. Holes for forming voids 161. Void 170. Etching resist 180. Holes for end face connection 181. End face connection terminal 182. Cutting line 190. Plating

Claims (18)

[Claims] 1. A two terminal part (201), a pair of discharge gap forming lands (202), a wiring part (203) connecting the terminal part (201) and the discharge gap forming land (202), A gap layer comprising an insulating layer (1) that supports these, and the insulating layer (1) is interposed between two discharge gap forming lands (202).
(101), the pair of discharge gap forming lands (202), the terminal portion (201) and the wiring portion (203) from both sides of the protective layer (1
02), which has at least three insulating layers, and has a hole (3) in which the gap forming land (202) is exposed, the gap forming land (202) protruding from the inner wall of the hole (3). A chip-type electrostatic protection element that is characterized by 2. The shortest distance of the discharge gap is 5 to 150 μm.
The chip type electrostatic protection element according to claim 1, wherein the chip type electrostatic protection element is in the range of m. 3. The chip type electrostatic protection device according to claim 1, wherein the gap layer (101) is a resin selected from a fluorine resin and a polyimide resin. 4. The protrusion height of the gap forming land (202) from the inner wall surface of the hole (3) is in the range of 5 to 100 μm. Chip type static electricity protection element. 5. A method according to claim 1, Making holes (3) in the double-sided copper clad laminate, b. By selectively removing the conductor layers on both sides by etching, the pair of discharge gap forming lands (202) and the wiring portion (20
Manufacturing a substrate having 3) and c. A step of laminating and adhering an insulating material which will be the protective layer (102) and a metal foil (401) on the outer side of both sides of this substrate, d. In the laminated adhesive, the wiring part (20
Drilling through holes (4) so as to cut 3), e. A step of converting the entire surface of the metal foil (401) and the inner wall of the through hole (4) into a conductor, f. Place the terminal (201) around the through hole (4) with a metal foil.
Forming by selective etching removal of (401), g. By cutting from the center of the through hole (4), cutting into individual chip type electrostatic protection elements,
And the discharge gap forming land (202) exposed on the inner wall of the hole (3) by plating is protruded from the inner wall surface of the hole (3) between steps a and b or between steps b and c. A method of manufacturing a chip-type electrostatic protection element, which comprises steps. 6. Instead of steps a and b, h. By selectively etching away the conductor layers of the double-sided copper-clad laminate, a pair of discharge gap forming lands (20
Manufacturing a substrate having 2) and a wiring part (203), i. The method for manufacturing a chip-type electrostatic protection element according to claim 5, further comprising a step of laminating and adhering an insulating layer to be a protective layer (102) on both surfaces of the substrate and forming a hole (3). 7. Instead of steps a and b, j. A pair of discharge gap forming lands (202) and a pair of discharge gap forming lands (202) and a pair of discharge gap forming lands (202) and wiring (203) are provided on two single-sided copper clad laminates, respectively. Forming by selectively removing by etching, k. A step of making a pair of discharge gap forming lands (202) face each other so as to face each other, interposing an insulating adhesive layer base material to be the gap layer (101) therebetween, and laminating and adhering the substrate, m. Making holes (3) in this substrate, n. The chip type electrostatic protection according to claim 5, further comprising a step of plating the discharge gap forming land (202) exposed on the inner wall of the hole (3) of the substrate to project the wiring from the inner wall surface. Device manufacturing method. 8. A step of forming a hole (3) and a protective layer for forming the hole (3).
Smear for contacting the gap layer (101) exposed on the inner wall of the hole (3) and, in some cases, the protective layer (102) with a liquid capable of dissolving the insulating layer to be formed during the step of closing with the (102). The method for manufacturing a chip-type electrostatic protection element according to claim 5, further comprising a step of performing treatment. 9. The chip-type static electricity according to claim 8, wherein the liquid capable of dissolving the insulating layer is selected from concentrated sulfuric acid, a permanganate-based solution, and a chromic acid-based solution. Manufacturing method of protective element. 10. The method for manufacturing a chip-type electrostatic protection device according to claim 5, wherein the copper-clad laminate is an insulating substrate on which a metal foil is laminated and adhered. 11. The chip-type electrostatic protection according to claim 5, wherein the copper-clad laminate has an insulating substrate on which a metal layer is formed by vapor-phase or liquid-phase plating. Device manufacturing method. 12. The chip type static electricity according to claim 5, wherein the material forming the gap layer (101) is a resin selected from a fluorine resin and a polyimide resin. Manufacturing method of protective element. 13. The fluororesin material is polytetrafluoroethylene resin, ethylene / tetrafluoroethylene copolymer, tetrafluoroethylene / hexafluoropropylene copolymer, tetrafluoroethylene / perfluoroalkoxyethylene copolymer, fluorine. 13. The method for manufacturing a chip-type electrostatic protection element according to claim 12, wherein the resin is selected from a modified resin obtained by modifying a resin based on another organic resin. 14. A gap forming land (20) protruding from an inner wall.
The method for manufacturing a chip-type electrostatic protection element according to any one of claims 5 to 12, wherein the shortest distance between the gaps in 2) is in the range of 5 to 150 µm. 15. In the laminating and adhering insulating material after drilling the hole (3), the insulating material used at this time is a low-flow insulating material that hardly flows into the hole (3). The manufacturing method of the chip-type electrostatic protection element according to any one of 5 to 14. 16. The method for manufacturing a chip-type electrostatic protection element according to claim 15, wherein the low-flow insulating material is a thermosoftening resin material. 17. The method for manufacturing a chip-type electrostatic protection element according to claim 16, wherein the thermosoftening resin material is a fluorine resin material. 18. The method of manufacturing a chip type electrostatic protection device according to claim 16, wherein the low flow insulating material is a high molecular weight epoxy polymer.