JPH10302605A - Chip fuse and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip fuse and a manufacturing method thereof which is superior to a formation accuracy (thickness and width of wiring) of a current protection device, is capable of controlling head radiation, smoking and firing by using an organic resin-made insulating substrate, and has a high insulation resistance after fusing and a high reliability. SOLUTION: This chip fuse comprises an organic resin-made insulating substrate 1; and a pair of electrodes 2 arranged at both ends of this organic resin- made insulating substrate 1; and a wiring part 3 for current protection device wired between the electrodes 2 and stored in the interior of the organic resin- made insulating substrate 1; and a current protection device 4. In this case, the current protection device 4 is supported by an organic resin layer with an excellent tracking characteristic and has a gap at one surface of the device 4 and a thickness of the device 4 ranges from 3 μm to 8 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a chip fuse and a method for manufacturing the same.

[0002]

2. Description of the Related Art A current protection element is used to protect an electronic device from overcurrent. The current protection element is connected between a power supply circuit and an electric circuit. When an overcurrent flows, a wiring in the current protection element is cut. Then, the electric circuit is protected by interrupting the current. Such an element is called a fuse as a general name, and in order to be called a fuse, it is necessary to satisfy characteristics defined in various standards.
With the diversification of electronic devices, there is a need for current protection elements having characteristics different from those of conventional fuse standards.

In the overcurrent protection device, an electronic switch using a thyristor or a transistor can be used in addition to the above-described current protection element. In such a case, the number of circuit components increases. Since the power consumed by the protection circuit also increases, it is not necessarily suitable for applications requiring miniaturization and low power consumption, such as portable devices operated by batteries.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 60-143544, silver or silver-palladium is used for the first layer on the ceramic substrate, nickel layer is used for the second layer, and third layer is used for the third layer.
It is known that three conductive layers of solder or tin are formed on the layers to improve the fusing characteristics at the time of soldering. Also,
This publication also discloses that the surface of the conductive layer is covered with a nonflammable (flame retardant) resin such as a silicone resin.

[0005]

However, when a current protection element (fuse) is provided on a ceramic substrate, the ceramic substrate has a low thermal resistance. However, there is a problem in that even if it is covered, the heat dissipation is high and the current value to be blown often varies depending on the ambient temperature.

In order to solve the problem of the ceramic substrate, there is a method of using an insulating substrate made of an organic resin. However, when the resin of the substrate is an epoxy resin, a phenol resin, a polyimide resin, or the like, it easily emits smoke or burns. There was a problem that.

An object of the present invention is to provide a highly reliable chip fuse which is excellent in suppressing smoke and ignition and has high insulation resistance after fusing and a method of manufacturing the same.

[0008]

As shown in FIG. 3, a chip fuse according to the present invention comprises an organic resin insulating substrate 1 and a pair of electrodes 2 provided at both ends of the organic resin insulating substrate 1.
In a chip fuse formed of a current protection element wiring portion 3 and a current protection element 4 formed between the electrodes 2 and housed inside the organic resin insulating substrate 1, the current protection element 4 It is supported by an organic resin layer 5 having high property, a gap 6 is provided on one surface thereof, and the thickness of the current protection element 4 is in the range of 3 to 8 μm.

Such a chip fuse comprises: a. As shown in FIG. 1A, a copper foil 102 having a thickness of 3 to 8 μm and an organic resin layer 103 formed on one surface thereof is bonded to a base material 120 on the organic resin layer 103 side.
Step of manufacturing 00 b. Unnecessary portions of the copper foil 102 of the laminate 100 are removed by etching to form a plurality of current protection element wiring portions 3 and current protection elements 4 as shown in FIG. 1B, c. Separately, a step of manufacturing the insulating spacer 200 having the hole 104 (not shown), d. As shown in FIG. 1 (c), the surface of the laminate 100 on which the current protection element wiring section 3 and the current protection element 4 formed in the step b are formed, the current protection element 4 is formed.
An insulating spacer 200 having a hole 104 formed therein is overlapped, and a laminate 300 having an insulating layer 302 formed on one surface of a copper foil 301 is further laminated.
00, and lamination bonding as shown in FIG. 1 (d), e. As shown in FIG. 1 (e), a step of drilling a hole 11 so as to penetrate the current protection element wiring portion 3 of the laminated adhesive; f. As shown in FIG. 1 (f), a step of plating 12 on the laminated adhesive having a hole 11 formed therein to convert the inner wall of the hole 11 into a conductor, g. 1g, removing unnecessary portions of copper by etching to form an electrode 2 connected to a conductor on the inner wall of the hole 11, h. As shown in FIG. 1 (h), the hole 11 is cut so as to be vertically divided, and the chip 11 is cut into individual chip fuses so that this portion becomes the electrodes 2 at both ends. I do.

Further, in place of the step a, the first copper layer 111 having a thickness in the range of 1.10 to 50 μm
Composite metal foil comprising a second copper layer 112 having a thickness in the range of 3 to 8 μm, and an intermediate layer 113 of nickel or an alloy thereof having a thickness of 1 μm or less provided between the two copper layers. An organic resin varnish is applied to the second copper layer 112 side of 110 and dried to form an organic resin layer 103, and the organic resin layer 103 is laminated and adhered so as to come into contact with the base material 120,
By using the process of manufacturing the laminated board 100, the handleability of a thin copper foil can be improved.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The organic resin layer 103 in contact with the current protection element wiring section 3 used in the present invention needs to have high tracking resistance. The tracking resistance refers to the degree to which tracking (a trace of the flow of current) is not formed by a voltage applied to the surface, and is described in IEC Publication (International Electrotechnical Commission official recommendation standard) 112 "Solid state in wet state". Method of Determining Comparative Tracking Index and Guaranteed Tracking Index of Insulating Material "is more preferably a PLC-0 class. This class is
As specified in IEC Publication (International Electrotechnical Commission officially recommended standard) 112, one drop of the electrolyte is dropped every 30 seconds while a voltage is applied between the electrodes formed on the test piece, It is an index of tracking property determined by a voltage that causes a permanent carbonized conductive path when 50 drops are dropped, and is a PLC-0 class.
This shows that the material has sufficient tracking resistance even when the applied voltage is 600 V or more.

The thickness of the organic resin layer 103 is 5 μm to
It is preferably in the range of 200 μm,
More preferably, it is in the range of 00 μm. If it is less than 5 μm, the tracking resistance cannot be sufficiently exhibited, and if it exceeds 200 μm, the effect of the void on the resin side decreases. The organic resin layer 103 can be formed by applying a varnish to a copper foil on which the current protection element wiring section 3 and the current protection element 4 are to be formed, or by applying an organic resin varnish to a PET film or the like. Alternatively, it can be manufactured by bonding an organic resin film to a copper foil for forming the current protection element wiring portion 3 and the current protection element 4.

The organic resin layer 103 can be formed from a polyvinyl butyral resin, an n-butylated melamine resin, an o-cresol novolak type epoxy resin, adipic acid, dimethyltriaminethiol, and pyrogallol. 120 parts by weight of polyvinyl butyral resin, 74 parts by weight of n-butylated melamine resin, 20 parts by weight of o-cresol novolak type epoxy resin, 1 part by weight of adipic acid, 0.5 parts by weight of dimethyltriaminethiol, pyrogallol Is preferably 1.5 parts by weight.

If the thickness of the current protection element 4 is less than 3 μm, it is difficult to control the thickness accuracy, and it is difficult to avoid the occurrence of pinholes. It becomes difficult, and it becomes difficult to perform fusing at the time of overcurrent application with high accuracy. When the device is portable and a battery is used, the fusing current is 600 to 200.
Since it is in the range of 0 mA, the range of 3 to 8 μm is preferable for forming such a circuit of the fusing current.

If the thickness of the current protection element wiring portion 3 is too small, the area for connection with the electrode portion becomes small, and the resistance value generated thereby becomes large, and the chip fuse is connected to the power supply side of the normal circuit. For this reason, the voltage may drop to the power supply voltage, which is not preferable. If the thickness is too large, it becomes difficult to process the wiring portion of the current protection element.
It is preferably in the range of 0 μm.

To achieve such a thickness, FIG.
As shown in (d), between the step b and the step c,
The plating can be performed by plating a portion of the copper foil having a thickness of 3 to 8 μm to be the current protection element wiring portion 3 so as to have a thickness of 10 to 50 μm.

In order to achieve such a thickness, the first copper layer 111 can be left as it is when the above-described three-layer composite metal foil 110 is used. Then, a4. A step of etching and removing at least a portion of the first copper layer 111 to be the current protection element 4; a5. Further, a step of etching and removing a portion of the intermediate layer 113 exposed by the above step (FIG. 2)
(E). ), Can also be performed.

The resin flow at the time of laminating and bonding the insulating spacers 200 having the holes 104 used in step c is preferably 200 μm or less. As the insulating material that can be used, the resin flow at the time of laminating and bonding is 200 μm or less. , A prepreg, a resin film, etc., and commercially available prepregs include, for example, GEA-E-679N (trade name, manufactured by Hitachi Chemical Co., Ltd.), and commercially available resin films include, for example, GF3500 ( Hitachi Chemical Co., Ltd. product name). Also, the cured insulating material can be bonded with an adhesive, and at this time, the thickness of the adhesive is reduced, and the hole is formed at the same time as the insulating material to reduce the resin flow into the hole. Can be. As such a cured insulating material, a material obtained by etching a copper foil from a copper-clad laminate used for a normal wiring board can be used. Resin or the resin used for the organic resin layer having high tracking resistance described above can be used.

[0019]

【Example】

Example 1 As the organic resin layer 103, the composition ratio was 120 parts by weight of polyvinyl butyral resin, 74 parts by weight of n-butylated melamine resin, 20 parts by weight of o-cresol novolak type epoxy resin, and 1 part by weight of adipic acid. Dimethyltriamine thiol, 0.5 parts by weight of pyrogallol, 250 parts by weight of methanol as a solvent, 190 parts by weight of methyl ethyl ketone, and 190 parts by weight of toluene. Adjust, PET
Coat the film with varnish, at 80 ° C for 5 minutes, then 140
After drying at 5 ° C. for 5 minutes, an organic resin film having a thickness of 50 μm was prepared. Thereafter, a copper foil 102 having a thickness of 5 μm on which the current protection element wiring section 3 and the current protection element 4 are to be formed, and a MCL-E- 679 (manufactured by Hitachi Chemical Co., Ltd., product name)
70 ° C., time 60 minutes, pressure 50 kg / cm ² ,
The laminate was bonded by heating and pressing to produce a laminate 100 as shown in FIG. Next, as shown in FIG. 2D, the thickness of the current protection element wiring portion 3 was increased by 10 μm by electrolytic copper plating. Thereafter, using an electrodeposition resist formed by electrodeposition of an ultraviolet-curing type resist as an etching resist, the electrodeposition resist is formed by baking and developing, and unnecessary portions of the copper foil 102 are removed by etching to remove the current protection element wiring portion 3 and the current. The pattern of the protection element 4 was formed. At this time, the pattern is arranged so that a plurality of current protection element wiring portions 3 are vertically connected in series with the current protection element 4 interposed therebetween.
In the horizontal direction, the rows were arranged in parallel (see FIG. 1).
(B). ). Separately, as an insulating spacer 200,
MCL-E- is a double-sided copper-clad laminate of 0.2mm thickness
679 (manufactured by Hitachi Chemical Co., Ltd.), copper foil on both sides were removed by etching, and GF3500 (Hitachi Chemical Co., Ltd., trade name), a 25 μm-thick adhesive sheet, was superimposed on both surfaces and drilled. A hole 104 having a diameter of 0.8 mm for forming a gap was formed. Next, as shown in FIG. 1C, the formed product of the current protection element wiring portion 3 and the current protection element 4 and the insulating spacer 200 having the hole 104 are overlapped.
Further, MCL-E-6, which is a laminate with a single-sided copper foil (thickness: 18 μm) having a thickness of 0.2 mm as the laminate 300.
79 (trade name, manufactured by Hitachi Chemical Co., Ltd.)
1 is positioned outside, and as shown in FIG. 1D, the temperature is 180 ° C., the time is 90 minutes, the pressure is 50 kg / cm ^2.
The layers were bonded by heating and pressing under the following conditions. Next, FIG.
As shown in FIG. 1, a hole 11 for connection is made in the laminated adhesive, plating 12 is performed as shown in FIG. 1 (f), and the inside of the hole 11 for connection is made conductive. As shown in the figure, the electrode 2 was formed by removing unnecessary copper by etching.

Example 2 The composition ratio of the organic resin layer 103 was 120 parts by weight of polyvinyl butyral resin, 74 parts by weight of n-butylated melamine resin, 20 parts by weight of o-cresol novolac type epoxy resin, and adipic acid. 1 part by weight, 0.5 part by weight of dimethyltriaminethiol, 1.5 parts by weight of pyrogallol, 250 parts by weight of methanol as a solvent, 190 parts by weight of methyl ethyl ketone, and 190 parts by weight of toluene were dissolved in a mixed solvent. Adjust resin varnish, PET
Coat the film with varnish, at 80 ° C for 5 minutes, then 140
After drying at 5 ° C. for 5 minutes, an organic resin film having a thickness of 50 μm was prepared. Thereafter, a copper foil 102 having a thickness of 5 μm on which the current protection element wiring section 3 and the current protection element 4 are to be formed, and a MCL-E- 679 (manufactured by Hitachi Chemical Co., Ltd., trade name), the organic resin film was interposed, and heated and pressed under the conditions of a temperature of 170 ° C., a time of 60 minutes, and a pressure of 50 kg / cm ² , thereby laminating and bonding. The laminated board 100 was produced. Next, as shown in FIG. 2D, the thickness of the current protection element wiring portion 3 was increased by 10 μm by electrolytic copper plating. Next, a UV-curable resist film, SR
-3000 (trade name, manufactured by Hitachi Chemical Co., Ltd.) is laminated, baked and developed to form an etching resist, unnecessary portions of the copper foil 102 are removed by etching, and the current protection element wiring section 3 and the current protection are removed. The pattern of the element 4 was formed. At this time, the pattern was formed such that a plurality of current protection element wiring portions 3 were arranged in series in the vertical direction with the current protection element 4 interposed therebetween, and the rows were arranged in parallel in the horizontal direction. Separately, MCL-E-67 which is a double-sided copper-clad laminate having a thickness of 0.2 mm is used as the insulating spacer 200.
9 (manufactured by Hitachi Chemical Co., Ltd., trade name) was etched off copper foil on both sides, and on both sides GF3500 (Hitachi Chemical Industry Co., Ltd.
(Trade name) were stacked, and a hole for forming a gap having a diameter of 0.8 mm was formed. The formed products of the current protection element wiring section 3 and the current protection element 4 are superimposed on the insulating spacer 200 having the holes, and the laminated board 300 is provided with a 0.2 mm thick single-sided copper foil (18 μm thick). MCL-E-67 which is a plate
9 (manufactured by Hitachi Chemical Co., Ltd., trade name)
Was placed on the outside, and heated and pressed under the conditions of a temperature of 180 ° C., a time of 90 minutes, and a pressure of 50 kg / cm ² to perform lamination bonding. A hole 11 for connection having a diameter of 0.8 mm was made in the laminated adhesive, plating 12 was performed, the inside of the hole for connection was made conductive, and then the electrode 2 was formed by removing unnecessary copper by etching.

Embodiment 3 As shown in FIG. 2A, a first copper layer 111 having a thickness of 15 μm, a second copper layer 112 having a thickness of 5 μm, and
A composite metal foil having a nickel-phosphorus alloy layer having a thickness of 0.2 μm was prepared as an intermediate layer 113 of two copper layers. Composition ratio is 120 parts by weight of polyvinyl butyral resin, n-
74 parts by weight of butylated melamine resin, 20 parts by weight of o-cresol novolak type epoxy resin, and 1 part of adipic acid
Parts by weight, 0.5 parts by weight of dimethyltriaminethiol,
And a resin varnish obtained by dissolving 1.5 parts by weight of pyrogallol, 250 parts by weight of methanol as a solvent, 190 parts by weight of methyl ethyl ketone, and 190 parts by weight of toluene in a second copper layer of the metal foil. It was coated on the 112 side and dried at 80 ° C. for 5 minutes and further at 140 ° C. for 5 minutes to prepare a 50 μm-thick composite metal foil with an organic resin layer. As shown in FIG. 2B, the base material 120 having a thickness of 0.2
MCL-E-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.), which is a single-sided copper-clad laminate having a thickness of 1 mm, was prepared by laminating resin-prepared copper foils with each other on a resin surface at a temperature of 170 ° C.
Under the conditions of a pressure of 50 kgf / cm ² and a pressure of 50 kgf / cm ² for 60 minutes, the layers were laminated and integrated. Next, the first copper layer 111 is removed by etching, the intermediate layer 113 is removed, and the second copper layer 112 is exposed (shown in FIG. 2C).
Unnecessary portions of the copper layer 112 are removed by etching in the same manner as in Example 1, a plurality of current protection elements 4 are formed, and the thickness of the current protection element wiring portion 3 is reduced to 10 by electrolytic copper plating.
The thickness was increased by μm (shown in FIG. 2D). Thereafter, a chip fuse substrate was manufactured in the same manner as in Example 1.

Example 4 A first copper layer 111 having a thickness of 15 μm, a second copper layer 112 having a thickness of 5 μm, and nickel having a thickness of 0.2 μm as an intermediate layer 113 between the two copper layers. -A composite metal foil having a phosphorus alloy layer was prepared. The composition ratio was 120 parts by weight of polyvinyl butyral resin and 7 parts of n-butylated melamine resin.
4 parts by weight, 20 parts by weight of o-cresol novolak type epoxy resin, 1 part by weight of adipic acid, 0.5 part by weight of dimethyltriaminethiol, and 1.5 parts by weight of pyrogallol.
A resin varnish in which parts by weight were dissolved in the same solvent as in Example 3 was applied to the second copper layer 112 side of the metal foil, dried at 80 ° C. for 5 minutes, and further dried at 140 ° C. for 5 minutes. , Thickness 5
A copper foil with an organic resin layer of 0 μm was produced. MCL which is a single-sided copper-clad laminate having a thickness of 0.2 mm as the base material 120
-E-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.)
Under a condition of a temperature of 170 ° C., a time of 60 minutes, and a pressure of 50 kgf / cm ² , heating and pressurization were performed to integrate the layers. Next, the portion of the first copper layer 111 other than the portion serving as the current protection element wiring portion 3 is removed by etching, and the exposed intermediate layer 113 is further removed.
After exposing the second copper layer 112, unnecessary portions of the second copper layer 112 are removed by etching in the same manner as in the first embodiment.
A plurality of current protection elements 4 were formed (shown in FIG. 2E). Thereafter, a chip fuse substrate was manufactured in the same manner as in Example 1.

The chip fuse substrates manufactured in Examples 1 to 4 were cut along the cutting line as shown in FIG. The conductor width of the current protection element was 0.05 mm, and the resistance was about 180 mΩ. As a result of performing 20 fusing tests each, the resistance value after fusing is over 10 megohms,
Gigaohm level. No ignition or smoke was found in any of the items.

[0024]

As described above, the chip fuse of the present invention is capable of accurately forming wiring without ignition or smoking, and capable of controlling the conduction resistance of the current protection element, and having a copper thickness as thin as 3 to 8 μm. Since this portion is formed by the foil, it is sensitive to overcurrent, and thus has excellent fusing characteristics. It also has excellent insulation properties after fusing.

[Brief description of the drawings]

1 (a) to 1 (h) are views showing respective steps for explaining one embodiment of the present invention.
(C)-(g) are sectional views, and (b) and (h) are plan views.

FIGS. 2A to 2E are cross-sectional views showing steps for explaining another embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view showing one embodiment of the present invention.

[Explanation of symbols]

1. 1. Organic resin insulating substrate Electrode 3. 3. Current protection element wiring section Current protection element 5. 5. Organic resin layer having tracking resistance Void 11. Hole 12. Plating 100. Laminated board 102.
Copper foil 103. Organic resin layer 110.
Composite metal foil 111. First copper layer 112.
Second copper layer 113. Middle layer 120.
Base material 200. Insulating spacer 300.
Laminated plate 301. Copper foil 302.
Insulating layer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Joru Taniguchi 1500, Oji, Shimodate-shi, Ibaraki Pref.

Claims (11)

[Claims] An organic resin insulating substrate, a pair of electrodes provided at both ends of the organic resin insulating substrate, wiring formed between the electrodes, and housed inside the organic resin insulating substrate. In the chip fuse composed of the current protection element wiring portion and the current protection element, the current protection element is supported by an organic resin layer having high tracking resistance, a gap is provided on one surface thereof, and the current protection element has a thickness of 3 mm. A chip fuse having a size of about 8 μm. 2. An organic resin layer having high tracking resistance, which supports a current protection element, comprises a polyvinyl butyral resin,
The chip fuse according to claim 1, comprising an n-butylated melamine resin, an o-cresol novolak type epoxy resin, adipic acid, dimethyltriaminethiol, and pyrogallol. 3. The thickness of the current protection element wiring portion is 10 to 50.
The chip fuse according to claim 1, wherein the diameter of the chip fuse is in a range of μm. 4. A method according to claim 1, wherein Although an organic resin layer (103) is formed on one side of a copper foil (102) having a thickness of 3 to 8 μm, a substrate (120) is laminated and adhered to the organic resin layer (103) side, and a laminate (100) is formed. Step of making b. Removing unnecessary portions of the copper foil (102) of the laminate (100) by etching to form a plurality of current protection element wiring portions (3) and current protection elements (4); c. Separately manufacturing a spacer (200) having a hole (104); d. The current protection element of the laminate (100) on which the current protection element wiring portion (3) and the current protection element (4) produced in the step b are formed
On the surface on which (4) is formed, an insulating spacer (200) having a hole (104) formed in the step c is overlapped, and further, a laminated plate in which an insulating layer (302) is formed on one surface of a copper foil (301) (300), its insulating layer
Stacking (302) so as to be in contact with the insulating spacer (200) and laminating and bonding; e. Making a hole (11) so as to penetrate the current protection element wiring portion (3) of the laminated adhesive; f. Plating (12) the laminated adhesive having the holes (11), and converting the inner walls of the holes (11) into conductors; g. Removing unnecessary portions of copper by etching to form an electrode (2) connected to a conductor on the inner wall of the hole (11); h. By cutting so that the hole (11) is vertical,
A step of cutting into individual chip fuses such that this portion becomes the electrodes (2) at both ends. 5. Between the step (a) and the step (b), a copper foil (12) having a thickness of 3 to 8 μm
5. The method according to claim 4, further comprising a step of performing plating so as to have a thickness of about 50 [mu] m. 6. The method according to claim 5, wherein an organic resin having high tracking resistance is used for the organic resin layer (103) formed on the copper foil (102) in the step (a). . 7. A first electrode having a thickness in the range of 1.10 to 50 μm.
Copper layer (111) and a second copper layer having a thickness in the range of 3 to 8 μm
(112) and a thickness of 1 μm provided between the two copper layers.
m, and an intermediate layer (113) of nickel or an alloy thereof having an intermediate layer (113). An organic resin varnish is applied to the second copper layer (112) side of the composite metal foil (110) and dried to form an organic resin layer (103). To form
A step of laminating and bonding the organic resin layer (103) so as to be in contact with the substrate (120) to produce a laminate (100); a2. A step of etching and removing only the first copper layer (111); a3. A step of etching and removing only the intermediate layer (113); b1. Forming a plurality of current protection element wiring portions (3) and current protection elements (4) by etching and removing unnecessary portions of the second copper layer (112); c. Separately, a step of manufacturing an insulating spacer (200) having a hole (104), d1. The hole (104) prepared in the step c was opened on the surface of the formed current protection element wiring part (3) and the current protection element (4) formed in the step b1 on which the current protection element (4) was formed. Lay the insulating spacer (200), and further add an insulating layer on one side of the copper foil (301).
Stacking the laminated plate (300) having the (302) formed thereon such that the insulating layer (302) is in contact with the insulating spacer (200), and laminating and adhering; e. Making a hole (11) so as to penetrate the current protection element wiring portion (3) of the laminated adhesive; f. Plating (12) the laminated adhesive having the holes (11), and converting the inner walls of the holes (11) into conductors; g. Removing unnecessary portions of copper by etching to form an electrode (2) connected to a conductor on the inner wall of the hole (11); h. By cutting so that the hole (11) is vertical,
A step of cutting into individual chip fuses such that this portion becomes the electrodes (2) at both ends. 8. A thickness of 3 to 8 μm between step a3 and step b1.
m copper foil (112) in the location to become the current protection element wiring part (3),
8. The method according to claim 7, further comprising a step of performing plating so as to have a thickness of 10 to 50 [mu] m. 9. A first layer having a thickness in the range of 1.10 to 50 μm.
Copper layer (111) and a second copper layer having a thickness in the range of 3 to 8 μm
(112) and a thickness of 1 μm provided between the two copper layers.
m, and an intermediate layer (113) of nickel or an alloy thereof having an intermediate layer (113). An organic resin varnish is applied to the second copper layer (112) side of the composite metal foil (110) and dried to form an organic resin layer (103). To form
A step of laminating and bonding the organic resin layer (103) so as to be in contact with the substrate (120) to produce a laminate (100); a4. A step of etching and removing at least a portion of the first copper layer (111) to be a current protection element (4); a5. Further, a step of etching and removing a portion of the intermediate layer (113) of the composite metal foil (110) exposed in the step a4, b2. Forming a current protection element wiring portion (3) and a current protection element (4) by etching and removing unnecessary portions of the second copper layer (112); c. Separately producing a insulating spacer (200) having a hole (104); d2. The current protection element wiring portion (3) manufactured in the step b2
On the surface of the formed current protection element (4) on which the current protection element (4) was formed, an insulating spacer (200) having a hole (104) formed in the step c was overlapped, and further, a copper foil (301 A) laminating a laminated plate (300) having an insulating layer (302) formed on one side thereof so that the insulating layer (302) is in contact with the insulating spacer (200); and e. Making a hole (11) so as to penetrate the current protection element wiring portion (3) of the laminated adhesive; f. Plating (12) the laminated adhesive having the holes (11), and converting the inner walls of the holes (11) into conductors; g. Removing unnecessary portions of copper by etching to form an electrode (2) connected to a conductor on the inner wall of the hole (11); h. By cutting so that the hole (11) is vertical,
A step of cutting into individual chip fuses such that this portion becomes the electrodes (2) at both ends. 10. An organic resin layer (103) formed on the side of the second copper layer (112) in the step a1, wherein an organic resin having high tracking resistance is used. A method for producing the chip fuse according to any one of the above. 11. An organic resin layer comprising a polyvinyl butyral resin, an n-butylated melamine resin, an o-cresol novolak type epoxy resin, adipic acid, dimethyltriaminethiol, and pyrogallol. The method for producing a chip fuse according to any one of the above.