JP2010093258A - Ceramic chip assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ceramic chip assembly having the low-profile size and strength. <P>SOLUTION: The ceramic chip assembly includes a ceramic base having the semiconductor electrical characteristics, external electrodes each of which is formed at both opposite side surfaces on the ceramic base, a metal lead wire with a circular cross-sectional surface that is electrically and mechanically connected with each of the electrodes via an electrically conductive bonding means at one end and includes an outer diameter with the thickness greater than or equal to that of the side surfaces of the ceramic base, and a pair of insulating films that are bonded with each other through an insulating adhesive agent and seal the ceramic base, external electrodes, electrically conductive bonding means, and metal lead wire so that the other end of the metal lead wire may be exposed to the outside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ceramic chip assembly, and more particularly, to a thin ceramic chip assembly having an insulating protective film having a uniform film thickness and improved mechanical strength. The present invention also relates to a ceramic chip assembly that protects an internal ceramic chip from external loads, impacts, and friction, and that is less affected by the ceramic chip from the external environment. Furthermore, the present invention relates to a ceramic chip assembly which is inexpensive and can be continuously operated in a reel tape manner, and has excellent productivity and economy.

  As one method of mounting a ceramic chip having the electrical performance of a semiconductor such as a thermistor, a magnetic body or a piezoelectric body on a printed circuit board (PCB), a metal lead wire or a lead frame (lead) is attached to the ceramic chip. There is a method in which a ceramic chip assembly is formed by soldering frame), and then a lead wire or a lead frame is soldered to the conductive pattern of the printed circuit board to join the ceramic chip and the printed circuit board while being electrically connected. . In this case, since the ceramic chip having the electrical performance of the semiconductor has a low mechanical strength, it may be broken by an external load, impact and friction, or the electrical performance may be deteriorated by a change in the external environment such as moisture. Therefore, after the lead wire is soldered to the ceramic chip, an insulator is coated or formed on the connection portion between the ceramic chip and the lead wire and the ceramic chip.

  Such a ceramic chip assembly is required to be easily electrically and mechanically (mechanically) connected to a printed circuit board and to satisfy various characteristics. Furthermore, the ceramic chip assembly needs to be manufactured by a reel tape method, and is inexpensive and automatically mounted on a printed circuit board. Further, with the recent development of electronic and communication technologies, ceramic chip assemblies are required to have light and thin characteristics and high reliability with respect to the external environment.

FIG. 1 shows a conventional ceramic chip assembly in which circular metal lead wires and ceramic chip components are soldered by a soldering method.
As shown in the figure, the end portions of the lead wires 20 and 22 are fixed by solder 30 on the external electrodes 12 and 14 of the ceramic bare chip 10 having external electrodes 12 and 14 formed on the front and back surfaces, respectively. The ends of the ceramic bare chip 10 and the lead wires 20 and 22 are encased by an insulating protective film 40 such as epoxy formed by coating or dipping.

The ceramic bare chip 10 normally includes only thin external electrodes 12 and 14 that do not have internal electrodes, and these external electrodes 12 and 14 are usually formed on the front and back surfaces of the ceramic bare chip 10 having a large area. Is done. Thus, the ceramic bare chip 10 in which the internal electrode is not formed has a disadvantage that it is difficult to have various electrical performances.
The metal lead wires 20, 22 have a circular shape that is inexpensive and convenient for automation, and usually has a diameter of 0.15 mm to 0.5 mm.

However, such a conventional structure has the following disadvantages.
First, in order to protect the entire ceramic bare chip 10 and a part of the lead wires 20 and 22, an insulating protective film 40 such as epoxy is formed, but the lead wires 20 formed on the front and back surfaces of the ceramic bare chip 10, 22 is disadvantageous in that the thickness of the ceramic chip assembly 1 increases and irregularities are produced.

In addition, lead wires 20 and 22 are positioned on the front and back surfaces of the ceramic bare chip 10, and external loads, impacts, and friction applied to the front and back surfaces of the ceramic bare chip 10 are applied to the protruding lead wires 20 and 22. Due to the concentration, the ceramic bare chip 10 located under the lead wires 20 and 22 may be broken.
Further, the normal ceramic bare chip 10 is composed of only a semiconductor material, and has a disadvantage that its mechanical strength is weak against external impact and friction.

In addition, the size of the ceramic bare chip 10 is typically larger than the outer diameter of the lead wires 20, 22, limiting the protection of the ceramic bare chip against external loads, impacts and friction, and is not compatible with light, thin, short and small ceramic chip assemblies. There are disadvantages.
For example, in order to measure the temperature of a CPU of a computer, a ceramic chip assembly having a thermistor performance is inserted into the lower part of the CPU. At this time, the ceramic chip assembly is thin and has high mechanical strength, and the front and back surfaces. However, in the conventional structure shown in FIG. 1, it is difficult to realize such characteristics.

  On the other hand, in the conventional structure of FIG. 1, in order to reduce the thickness, a thin metal foil having a certain thickness, for example, about 0.15 mm is etched instead of the circular lead wires 20 and 22. Alternatively, a pressed sheet-shaped lead frame is used, and ceramic bare chip 10 or ceramic chip having external electrodes having lengths, thicknesses and widths of about 1 mm, 0.35 mm and 0.5 mm, respectively, is used for insulation. The protective film 40 can be sealed with heat and pressure using a pair of insulating films on which a hot melt adhesive is formed.

  However, according to such a modified structure, the price of the lead frame is higher than that of the circular metal lead wire, and it is difficult to continuously produce the reel tape method. Furthermore, the cross section of the lead frame is usually a thin thickness of about 0.15 mm, and the width is considerably wider than the thickness, for example, a rectangle of about 0.5 mm. The lead frame is inserted between these lead frames and soldered. Since the thickness of the ringed ceramic bare chip or the ceramic chip is thicker than the thickness of the lead frame, a portion protruding to the outside may be broken or damaged by an external load, impact or friction. That is, since the lead frame has a small thickness, there is a limit in physically protecting the internal ceramic bare chip or the ceramic chip from impact or friction applied from the horizontal or vertical direction. On the other hand, even when the thickness portion of the lead frame is erected in the width direction so as to contact the ceramic bare chip 10 or the ceramic chip, the ceramic chip is protected from external load, impact or friction applied from the vertical direction of the ceramic chip assembly. hard.

In addition, the lead frame having a rectangular cross section and the external electrode of the ceramic chip having a rectangular structure are in contact with each other and are soldered, so that the soldered area is small and the soldering strength is weak.
Furthermore, since the lead frame has a rectangular structure, it is inefficient to insert into the circular hole of the printed circuit board and solder, and the thin lead frame tends to return to its original state until it is fully bent. Yes, it is difficult to adhere to a certain part. Further, the lead frame may be cut in a thin thickness direction due to the force repeatedly applied.

Further, since the hot melt adhesive is melted by heat, there is a disadvantage that the adhesive force is lost and the ceramic chip cannot be protected when used at a high temperature.
The ceramic chip normally applied to the lead frame is a thin single layer ceramic bare chip in which no internal electrode is formed, and has a disadvantage that it is difficult to provide a ceramic chip assembly having various performances.

Japanese Utility Model Publication No. 6-31102

The present invention has been made in view of the above-described problems, and an object thereof is to provide a ceramic chip assembly having a small thickness and strength.
It is another object of the present invention to provide a ceramic chip assembly that prevents damage to the ceramic chip from external loads, impacts and friction.
It is another object of the present invention to provide a ceramic chip assembly in which a lead wire and a ceramic chip are electrically bonded and have a strong mechanical strength.

Another object of the present invention is to provide a ceramic chip assembly that is convenient for automation and economical by a reel tape method.
Another object of the present invention is to provide a ceramic chip assembly having an insulating protective film having a uniform thickness.
It is another object of the present invention to provide a ceramic chip assembly that reliably protects an internal ceramic chip from the external environment.

Another object of the present invention is to provide a ceramic chip assembly that can be used even at high temperatures.
Another object of the present invention is to provide a ceramic chip assembly having the same upper and lower structures and improved productivity.
It is another object of the present invention to provide a ceramic chip assembly that can easily realize various electrical characteristics by internal electrodes of the ceramic chip.

Another object of the present invention is that the lead wire is easily inserted and soldered to the printed circuit board, and is less likely to return to elasticity before it is fully bent, and is easily fixed to a certain portion. It is an object of the present invention to provide a ceramic chip assembly that is not cut by a given force.
It is still another object of the present invention to provide a ceramic chip assembly that has little influence on the ceramic chip when spreading two lead wires.

  The object is to provide a ceramic base having electrical characteristics of a semiconductor, external electrodes respectively formed on opposite side surfaces of the ceramic base, and one end bonded to each external electrode by an electrically conductive adhesive means. And a metal lead wire having an outer diameter equal to or greater than the thickness of the side surface of the ceramic base and having a circular cross section and an adhesive adhesive, and the other end of the metal lead wire is externally connected. A ceramic chip assembly including the ceramic base, the external electrode, the electrically conductive adhesive means, and a pair of insulating films for sealing the metal lead wires to expose the ceramic lead assembly.

  Further, the above object is to provide a ceramic base having electrical characteristics of a semiconductor, external electrodes respectively formed on opposite side surfaces of the ceramic base, and one end bonded to each external electrode by an electrically conductive bonding means. A metal lead wire having an outer diameter equal to or greater than a thickness of a side surface of the ceramic base and having a circular cross section, and the ceramic base so that the other end of the metal lead wire is exposed to the outside. This is achieved by a ceramic chip assembly including an external electrode, an electrically conductive bonding means and an insulating coating layer that seals and bonds the metal lead wire.

Preferably, the insulating coating layer may be wrapped by a pair of insulating films that are bonded to each other through an insulating adhesive.
Preferably, the thickness of the ceramic base is 0.2 mm to 0.6 mm, the length of the ceramic base has a dimension larger than the thickness and width, and the lead wire has a length of the ceramic base. The external electrode may be connected to extend in the vertical direction.

Preferably, an internal electrode electrically connected to the external electrode may be formed in the ceramic base.
Preferably, the ceramic base may be any one of a thermistor, a magnetic body, or a piezoelectric body having semiconductor electrical characteristics.
Preferably, the ceramic base may be partially formed on an insulating alumina substrate.

Preferably, the center of the cross section of the lead wire is positioned on an extension line from an intermediate position of the thickness of the ceramic base, and can have the same shape in the vertical direction.
Preferably, the metal lead wire may be any one of a copper-based, nickel-based, or iron-based metal having a diameter of 0.2 mm to 0.6 mm.
Preferably, the insulating adhesive may be any one of a thermoplastic hot melt or a curable adhesive.

Preferably, the bonding by the electrically conductive bonding means may be any one of soldering by a solder cream, bonding by a polymer adhesive having curability and electric conductivity, or spot welding.
Preferably, the insulating film may be any one of PET, PEN, PI, or a fluororesin film having a thickness of 0.015 mm to 0.07 mm.

The insulating coating layer may be any one of curable polymer resin or glass.
Preferably, all the end portions of the lead wire protrude from the ceramic base.
In addition, the above-described object is to prepare a ceramic base having external electrodes formed on opposite side surfaces and having semiconductor electrical characteristics, and to supply a ceramic base having a circular cross-section that is continuously supplied in a reel form. Forming a metal lead wire into a curve using a carrier tape to maintain contact between the metal lead wires and the ceramic-based external electrode; and the ceramic maintained in contact with the metal lead wires A step of bonding the external electrode of the base with an electrically conductive bonding means, and the external electrode and the lead wire are bonded and electrically connected by the electrically conductive bonding means, and then formed into a curve of the metal lead wire. Cutting the portion to separate the metal lead wire, and the other end of the metal lead wire is Sealing the ceramic base, the external electrode, the electrically conductive bonding means, and the metal lead wire by heat and pressure using a pair of insulating films coated with an insulating adhesive so as to be exposed to a part. This is achieved by a method of manufacturing a ceramic chip assembly comprising.

Preferably, the method may further include a step of automatically and continuously selecting a measuring instrument at both ends of the lead wire not sealed with the insulating film.
In addition, the above-described object is to prepare a ceramic base having external electrodes formed on opposite side surfaces and having semiconductor electrical characteristics, and to supply a ceramic base having a circular cross-section that is continuously supplied in a reel form. Forming a metal lead wire into a curve using a carrier tape to maintain contact between the metal lead wires and the ceramic-based external electrode; and the ceramic maintained in contact with the metal lead wires A step of bonding the external electrode of the base with an electrically conductive bonding means, and the external electrode and the lead wire are bonded and electrically connected by the electrically conductive bonding means, and then formed into a curve of the metal lead wire. Cutting the portion to separate the metal lead wire, and the other end of the metal lead wire is Dipping the ceramic base, the external electrode, the electrically conductive bonding means and the metal lead wire into a liquid coating adhesive so as to be exposed, and curing the insulating coating adhesive to form a solid Forming the insulating coating layer of the ceramic chip assembly.

  Preferably, the method may further include a step of automatically and continuously selecting a measuring instrument at both ends of the lead wire not sealed with the insulating coating layer.

According to the present invention, the following effects can be obtained.
1. A metal lead wire with a circular cross section is located on the external electrodes on both sides of the ceramic base, and the outer diameter of the lead wire is greater than the thickness of the ceramic base, so external loads, impacts and friction are applied to the lead wire. Absorbed and dispersed. Therefore, there is an advantage that the ceramic chip is protected from external pressure, impact and friction.

2. A metal lead wire having a circular cross section is electrically connected to and bonded to an external electrode in a length direction in which the size of the ceramic base is large, thereby having a wide bonding area and high bonding strength, and the thickness of the ceramic chip assembly. There is a thin advantage.
3. By using a metal lead wire having a circular cross section, it is convenient for the reel tape method and automation, and the manufacturing cost is low.

4). Various electrical characteristics can be realized by forming internal electrodes inside the ceramic base.
5). The ceramic is formed on an insulating ceramic base having a high mechanical strength, so that the mechanical strength is improved.
6). By using an insulating film, an insulating protective film having a thin and uniform thickness can be provided, and the surface is smooth and strong against external friction.

7). When a thermosetting material is used as the insulating adhesive or the insulating coating layer, the thermosetting material is not melted again by heat.
8). When a hot melt adhesive is used as an insulating adhesive, it is inexpensive and highly productive.
9. When an insulating coating layer is formed inside the insulating film, there is an advantage that the ceramic chip is protected when the two lead wires are spread with force by more reliably protecting the inner ceramic chip from changes in the external environment.

10. A metal lead wire with a circular cross-section is easily inserted and soldered into a circular hole in a printed circuit board, and after soldering, it is less likely to return to its original shape before it is fully bent, so it is easy to place in a certain part There is an advantage that not only is it fixed, but also it is difficult to be cut by a force repeatedly applied.
11. When a polymer adhesive having a curable property and electrical conductivity and a spot welding method are used as the electrically conductive bonding means, use at a high temperature is easy.
12 The center of the lead wire is located on the extended line from the middle position of the thickness of the ceramic base, and has the same shape in the vertical direction, and is easy to automate and use.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 2 shows an example of a ceramic chip 100 applied to the present invention.
As shown in the figure, the ceramic chip 100 is composed of a ceramic base 110 having a hexahedral shape and electrical characteristics, and external electrodes 120 and 130 formed on opposite side surfaces of the ceramic base 110.

In one embodiment of the present invention, the ceramic chip may have a length, thickness and width of approximately 1 mm, 0.30 mm, and 0.5 mm, but the present invention is not limited thereto, and Has a similar size.
If the size of the ceramic chip is too small, it is difficult to automate the ceramic chip assembly by the reel tape method.

Preferably, the external electrodes 120 and 130 are formed at both ends in the direction in which the width of the ceramic base 110 is small, that is, in the x direction.
Preferably, an internal electrode having both ends electrically connected to the external electrodes 120 and 130 may be formed inside the ceramic base 110.
Preferably, the ceramic chip 100 is a surface-mount (SMD) ceramic chip 100 that can be surface-mounted by a vacuum pickup because its front and back surfaces are horizontal planes.

  As described above, the hexahedral ceramic chip 100 has a light, thin, and small shape, which is advantageous for automation, and has an advantage that it can be sorted at high speed by an automatic sorter and is inexpensive. In addition, the ceramic chip 100 has an advantage that it has internal electrodes and can realize various electrical characteristics. That is, the semiconductor ceramic base 110 has precise electrical characteristics due to the internal electrodes, and the electrical capacity can be easily adjusted.

  Preferably, the ceramic chip 100 may have a semiconductor ceramic base 110 formed on an insulating alumina substrate. In this case, the thickness of the alumina substrate is usually 0.2 mm to 0.4 mm, and the thickness of the semiconductor ceramic base is 0.02 mm to 0.1 mm. Therefore, the mechanical strength of the ceramic chip 100 is increased by the alumina substrate. High and resistant to external loads, impacts and friction.

3 shows a ceramic chip assembly 500 according to an embodiment of the present invention, FIG. 4 is a sectional view taken along line 4-4 of FIG. 3, and FIG. 5 is a plan view of FIG.
As shown in the drawing, metal lead wires 200 and 210 having a circular cross section in the horizontal direction are mechanically (mechanically) and electrically connected to both sides of the external electrodes 120 and 130 of the ceramic base 110 by an electrically conductive adhesive means, for example, a solder 230. Electrically connected. In addition, the ceramic base 110, the external electrode, the solder 230, and a part of the lead wires 200 and 210 are sealed and protected by heat and pressure by the two insulating films 300 and 310 bonded together by the insulating adhesive 320.

Preferably, the cross-sectional centers of the lead wires 200 and 210 can be positioned on an extension line from the middle position of the thickness of the ceramic base 110. In this case, since the top and bottom forms of the ceramic chip assembly 500 are equal, the productivity is good, and the ceramic chip 100 is protected from external loads, impacts, and friction applied from above and below.
Preferably, the two insulating films 300 and 310 have the same material and thickness, and the metal lead wires 200 and 210 have the same material and thickness.
Preferably, the diameter of the metal lead wires 200 and 210 having a circular cross section is greater than or equal to the thickness of the ceramic base 110.

Preferably, the length of the ceramic base 110 is longer than the width and thickness of the ceramic base 110.
Preferably, the ceramic chip 100 can be protected from changes in the external environment such as moisture by the insulating adhesive 320 formed between the insulating films 300 and 310.
<Ceramic chip 100>
The ceramic chip 100 includes a ceramic base 110 and external electrodes 120 and 130 that are joined to both side surfaces of the ceramic base 110 and are also electrically connected. As described above, the external electrodes 120 and 130 are formed to face both ends of the ceramic base 110 in the width direction.

The ceramic base 110 is a fired ceramic having electrical characteristics, and is preferably a semiconductor ceramic having the characteristics of a thermistor, magnetic body, or piezoelectric body, or a thermistor, magnetic body, or piezoelectric body on an insulating ceramic substrate. A semiconductor ceramic having a multilayer structure in which any one of them may be formed.
The ceramic base 110 has a hexahedral shape in which the front surface and the back surface are horizontal, and can be surface-mounted by a vacuum pickup. The dimensions of the ceramic base 110 are, for example, a width of 0.25 mm to 0.8 mm, a thickness of 0.20 mm to 0.6 mm, and a length of 0.5 mm to 1.6 mm.

Preferably, the upper and lower shapes of the ceramic chip assembly 500 can be made the same so that the cross-sectional centers of the lead wires 200 and 210 are located on an extension line from the middle position of the thickness of the ceramic base 110.
Preferably, the external electrodes 120 and 130 have both ends in the width direction (x direction in FIG. 2) of the ceramic base 110 so that the external electrodes 120 and 130 and the lead wires 200 and 210 are strongly bonded by the electrically conductive bonding means 230. Formed. At this time, since the lead wires 200 and 210 are extended in the length direction (y direction in FIG. 2) which is larger than the width and thickness of the ceramic base 110, the contact between the lead wires 200 and 210 and the ceramic base 110 is increased. The area can be increased. In this case, the ceramic chip assembly 500 is advantageous in having various performances while having a narrow width and a small thickness.
Preferably, the ceramic base 110 may be a single layer or a multilayer type, or a semiconductor ceramic formed on an insulating ceramic substrate such as an alumina substrate for mechanical strength.

The ceramic base 110 may or may not include an internal electrode. When the ceramic base 110 includes the internal electrode, the internal electrode is electrically connected to the external electrodes 120 and 130. When an internal electrode (not shown) is provided inside the ceramic base 110, it is easy to have precise electrical characteristics and adjustment of the electrical capacity is easy.
The external electrodes 120 and 130 are portions to which the lead wires 200 and 210 are fixed by the solder 230, and serve as an electrical path to the outside. The external electrodes 120 and 130 can be formed by a normal technique, for example, by dipping both sides of the ceramic base 110 with a metal paste and then plating nickel and tin on the metal paste.
<Metal lead wires 200 and 210 having a circular cross section>
The metal lead wires 200 and 210 having a circular cross section serve to transmit the electrical characteristics of the ceramic base 110 to necessary portions through the external electrodes 120 and 130 and the solder 230.

  In consideration of mechanical strength and electrical conductivity, any one of copper, copper alloy, iron, iron alloy, or metal wire made of nickel or nickel alloy can be used as the material. In addition, when an insulating wire having an insulating protective film formed thereon is used as the lead wires 200 and 210, the insulating protective film of the soldered portion and the portion soldered to the printed circuit board by the solder has a thermal or mechanical force. It is used after being removed by. In this case, the insulated wire may be an insulated enamel wire.

  As the lead wires 200 and 210, a lead wire having a circular cross section is used so that the adhesive strength with the external electrodes 120 and 130 is high and the automation of the reel tape method or the like is facilitated. Further, when a metal lead wire having a circular cross section is used, the workability is improved without causing a distortion phenomenon of the lead wires 200 and 210 during the continuous operation during the manufacturing process, and the printed circuit board formed in a circular shape. It is easy to insert into the holes and solder.

  However, a part of the metal lead wire having a circular cross section may be manufactured to have a cross section having a different shape as needed during the manufacturing process. For example, by extruding and flattening the portions existing in the insulating film excluding the portions to be bonded to the external electrodes 120 and 130 in the vertical direction, the thickness can be reduced. it can. Accordingly, the present invention includes all cases in which metal lead wires 200 and 210 having a circular cross section are manufactured continuously.

Referring to FIG. 4, when the cross section is circular, a large volume space is formed between the lead wires 200 and 210 and the external electrodes 120 and 130 around the contact portion. By filling the solder 230, the adhesive force between the lead wires 200 and 210 and the external electrodes 120 and 130, that is, the soldering strength is increased.
In addition, as shown in FIG. 4, by using metal lead wires 200 and 210 having a circular cross section having a diameter equal to or larger than the thickness of the ceramic base 110, when pressure or impact is applied vertically from the outside, Since pressure and impact are distributed to the lead wires 200 and 210, there is an advantage that the ceramic base 110 having low mechanical strength can be protected from external load, impact and friction.

Further, there is an advantage that the ceramic base 110 is protected from pressure and impact applied horizontally.
In addition, smooth insulating films 300 and 310 are formed on the ceramic base 110 and the lead wires 200 and 210, and insertion into a narrow gap between structures is easy.
Further, as described above, since the lead wires 200 and 210 are soldered to the external electrodes 120 and 130 in the length direction in which the dimension of the ceramic base 110 is large, the contact area increases and reliable soldering is performed. Possible and high soldering strength.

Also, the metal lead wires 200, 210 having a circular cross section provide an economical ceramic chip assembly 500 because they are cheaper and easier to automate than a pressed or etched rectangular cross section lead frame.
In addition, the metal lead wires 200 and 210 having a circular cross section are easily inserted into a circular hole of a printed circuit board, for example, a via hole and soldered, and have a certain thickness. Before, there is an advantage that there is little tendency to return to the original due to elasticity, it is easily fixed to a certain part, and it is difficult to be cut by a force repeatedly applied.

  When the ceramic chip assembly 500 is manufactured, the metal lead wires 200 and 210 having a circular cross section are continuously supplied in a reel state together with the carrier tape, and as shown in FIG. 5, a continuous forming process using the carrier tape is performed. The lead wires 200 and 210 are physically formed by contact with the external electrodes 120 and 130 of the ceramic chip 100, and then impregnated in a molten solder container, and the lead wires 200 and 210 and the external electrodes are formed by the solder 230. After 120 and 130 are soldered, both ends of the formed portion 250 of the lead wire are automatically cut by a press. Thereby, as shown in FIG. 5, the cut ends of the lead wires 200 and 210 protrude from the ceramic base 110. According to such a configuration, the protruding portion of the lead wires 200 and 210 can protect the ceramic chip 100 when the protruding portion of the lead wires 200 and 210 is forward and the ceramic chip assembly is pushed into a narrow gap.

As described above, the mechanical connection between the lead wires 200 and 210 and the external electrodes 120 and 130 is performed by the applied pressure of the formed portion 250 of the lead wire before the soldering by the solder. Thus, the lead wires 200 and 210 are made of one type of lead wire that is continuously supplied, and the thickness and material thereof are the same.
Although not shown, the carrier tape is supplied to continuously form the ceramic chip assembly 500, and is particularly necessary when cutting the formed ends of the lead wires 200, 210. It consists of paper or synthetic resin film.

Preferably, the metal lead wires 200 and 210 have a diameter of 0.2 mm to 0.6 mm.
<Electrically conductive bonding means 230>
The electrically conductive bonding means 230 joins and electrically connects the external electrodes 120 and 130 of the ceramic base 110 and the lead wires 200 and 210. When the ceramic chip assembly 500 is used at a low temperature, for example, less than 200 ° C., the electrically conductive bonding means 230 may be an ordinary solder that is inexpensive and convenient to use.

The working method is that when the lead wires 200 and 210 having the ceramic chip 100 inserted are continuously put into a solder container in which the solder is melted, the external electrodes 120 and 130 and the lead wires 200 and 210 are automatically moved by the solder 230. Soldered.
When the ceramic chip assembly 500 is used at a high temperature exceeding 200 ° C., the electrically conductive bonding means 230 preferably applies a thermosetting electrically conductive high temperature epoxy adhesive or spot welding or the like. be able to. In this case, the electrically conductive bonding means 230 provides reliable electrical and mechanical bonding even in places where the use temperature is high.

The electrically conductive bonding means 230 uses a normal bonding technique and material.
<Insulating films 300, 310>
The insulating films 300 and 310 are formed by adhering two insulating film tapes each coated with an insulating adhesive 320 such as a hot melt adhesive or a thermosetting adhesive to each other by heat and pressure. . When the hot melt adhesive is used, it is melted again by heat. Therefore, when the ceramic chip assembly is used at a high temperature, the adhesive strength is reduced by heat and it is difficult to protect the ceramic base.

Preferably, the hot melt adhesive is an EVA, polyurethane or polyester adhesive.
When a thermosetting adhesive is used, it is not melted by heat and can be used even at a high temperature. In particular, when a thermosetting silicone rubber adhesive is used, it has flexibility and elasticity and has an excellent waterproof function.

Preferably, the thermosetting adhesive is an epoxy or silicone rubber adhesive.
When a thermosetting adhesive is used, a liquid thermosetting adhesive is cured on the insulating films 300 and 310 while being cast or coated during the manufacturing process of the ceramic chip assembly 500.
At this time, the portion where the ceramic base 110 is located is completely sealed with the insulating films 300 and 310 and the insulating adhesive 320, and the other ends of the lead wires 200 and 210 are exposed. With such a structure, the insulating films 300 and 310 protect the ceramic chip 100 and the soldering portion from the outside, and provide insulation to certain portions of the lead wires 200 and 210.

In general, since the insulating films 300 and 310 have a thin and uniform film thickness, they provide reliable insulation and workability economically.
Further, when the ceramic chip assembly 500 is inserted and used between structures having a narrow gap, the surfaces of the insulating films 300 and 310 can be smooth to reduce external friction and avoid the concentration of external pressure. Can do.

Preferably, a heat resistant film such as Teflon (registered trademark), polyester, or polyimide can be used as the material of the insulating films 300 and 310, and the thickness may be 0.01 mm to 0.08 mm.
Preferably, the insulating films 300 and 310 and the insulating adhesive 320 have a heat resistance condition that satisfies a short-time soldering condition performed between both ends of the lead wires 200 and 210 where the insulating films 300 and 310 are not formed and the PCB.

In the above-described embodiment, the application of the insulating films 300 and 310 has been described as an example, but an insulating coating layer using an insulating coating adhesive may be used instead of the insulating film. FIG. 6 illustrates a ceramic chip assembly 600 according to another embodiment of the present invention.
Specifically, the insulating coating layer 400 can be formed by thinly insulating coating the ceramic chip, solder, and lead wire excluding the end of the metal lead wire with a thermosetting insulating coating adhesive such as epoxy or silicon rubber. . For this purpose, for example, an insulating epoxy or insulating silicon rubber is coated through a process of dipping liquid silicon rubber or coating with epoxy powder, and then cured by heat to form the insulating coating layer 400.

Preferably, the insulating coating layer 400 is made of any one of thermosetting epoxy resin, silicon rubber, or glass.
According to such a structure, compared with the case where an insulating film is applied, the overall size can be reduced, and since an expensive insulating film is not used, there is an advantage that the manufacturing cost is reduced.

Also, according to such a structure, a ceramic chip assembly 600 having a very small size can be manufactured. In particular, the width and thickness of the ceramic chip assembly 600 are very small.
Further, since the insulating coating layer 400 is made of a curable resin, it is prevented from being melted again by heat, has high reliability, and is easy to use at a high temperature.
Further, the insulating coating layer 400 formed between the two lead wires 200 and 210 prevents the force from being transmitted to the soldered portion when the both ends of the lead wires 200 and 210 are spread by force. The connection between the wires 200 and 210 and the external electrodes 120 and 130 is protected.

  On the other hand, on the ceramic chip 100 except the end of the metal lead wire, the solder and the lead wire for a more reliable insulating seal and to protect the ceramic chip 100 from external loads, impacts and friction. After the insulating coating layer 400 is formed by thinly insulating coating with a thermosetting insulating coating adhesive such as epoxy or silicon rubber, the insulating films 300 and 310 can be applied thereon.

In this case, the insulating coating 400 and the insulating films 300 and 310 provide a more reliable insulating seal and protect the ceramic chip 100 and the soldered portion from external loads, impacts and friction.
Although the embodiments of the present invention have been described above, various changes and modifications can be made by those skilled in the art. For example, the lead wire can be arbitrarily bent in the insulating film. Therefore, the scope of rights of the present invention should not be limited to the above-described embodiments, but should be determined by the appended claims.

1 shows a conventional ceramic chip assembly in which round metal lead wires and ceramic chip components are soldered by a soldering method. An example of the ceramic chip applied to this invention is shown. 1 illustrates a ceramic chip assembly according to an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. FIG. 4 is a plan view of FIG. 3. 6 shows a ceramic chip assembly according to another embodiment of the present invention.

DESCRIPTION OF SYMBOLS 100 Ceramic chip 110 Ceramic base 120, 130 External electrode 200, 210 Metal lead wire 230 Solder 300, 310 Insulating film 320 Insulating adhesive 500 Ceramic chip assembly

Claims (17)

A ceramic base having electrical characteristics of a semiconductor;
External electrodes respectively formed on opposite side surfaces of the ceramic base;
A metal lead wire having a circular cross section, one end of which is bonded to and electrically connected to each of the external electrodes by an electrically conductive bonding means, and has an outer diameter equal to or greater than the thickness of the side surface of the ceramic base;
An insulating protective material for sealing the ceramic base, the external electrode, the electrically conductive bonding means, and the metal lead wire so that the other end of the metal lead wire is exposed to the outside.
The ceramic chip assembly, wherein the insulating protective material includes a pair of insulating films or insulating coating layers that are bonded to each other with an insulating adhesive interposed therebetween. The ceramic base has a thickness of 0.2 mm to 0.6 mm, the length of the ceramic base has a dimension larger than the thickness and width, and the lead wire extends in a length direction of the ceramic base. The ceramic chip assembly according to claim 1, wherein the ceramic chip assembly is connected to the external electrode to be extended. The ceramic chip assembly according to claim 1, wherein an internal electrode electrically connected to the external electrode is formed in the ceramic base. The ceramic chip assembly according to claim 1, wherein the ceramic base is one of a thermistor, a magnetic body, and a piezoelectric body having electrical characteristics of a semiconductor. 2. The ceramic chip assembly according to claim 1, wherein a center of a cross section of the lead wire is located on an extension line from an intermediate position of the thickness of the ceramic base and has the same shape in the vertical direction. The ceramic chip assembly of claim 1, wherein the ceramic base is formed with a small thickness on an insulating alumina substrate. The ceramic chip assembly according to claim 1, wherein the insulating adhesive is any one of a thermoplastic hot melt and a curable adhesive. The adhesion by the electrically conductive adhesive means is any one of soldering by solder cream, adhesion by a polymer adhesive having curability and electrical conductivity, or spot welding. Of ceramic chip assembly. The ceramic chip assembly according to claim 1, wherein the insulating film is any one of PET, PEN, PI, or a fluororesin film having a thickness of 0.015 mm to 0.07 mm. The ceramic chip assembly according to claim 1, wherein the insulating coating layer is one of a curable polymer resin and glass. The ceramic chip assembly according to claim 1, wherein one end of the lead wire protrudes from the ceramic base. 2. The ceramic chip assembly according to claim 1, wherein the lead wire is an insulating-coated lead wire except for a portion connected to the external electrode. 3. The ceramic chip assembly according to claim 1, wherein a part of the metal lead wire having a circular cross section has a cross section having a different shape. 14. The part according to claim 13, wherein the part is formed by punching out and flattening a part existing in the insulating film excluding a part to be bonded to the external electrode. The ceramic chip assembly as described. A ceramic base having electrical characteristics of a semiconductor;
External electrodes respectively formed on opposite side surfaces of the ceramic base;
A metal lead wire having a circular cross section, one end of which is bonded to and electrically connected to each of the external electrodes by an electrically conductive bonding means, and has an outer diameter equal to or greater than the thickness of the side surface of the ceramic base;
An insulating coating layer for sealing and bonding the ceramic base, the external electrode, the electrically conductive bonding means and the metal lead wire so that the other end of the metal lead wire is exposed to the outside;
A ceramic chip assembly, comprising: a pair of insulating films which are bonded to each other with an insulating adhesive interposed therebetween and enclose the insulating coating layer. Preparing a ceramic base having external electrodes formed on opposite side surfaces and having semiconductor electrical characteristics, and continuously supplying;
Forming a metal lead wire having a circular cross section continuously supplied in a reel form into a curve using a carrier tape, and maintaining the metal lead wire in contact with the external electrode of the ceramic base between the metal lead wires; ,
Bonding the ceramic-based external electrode maintained in contact with the metal lead wire with an electrically conductive bonding means;
After the external electrode and the lead wire are bonded and electrically connected by the electrically conductive bonding means, cutting the formed portion of the metal lead wire into a curve, and separating the metal lead wire;
The ceramic base, the external electrode, the electrically conductive bonding means and the metal lead wire are heated with a pair of insulating films coated with an insulating adhesive so that the other end of the metal lead wire is exposed to the outside. Sealing with pressure, and a method for manufacturing a ceramic chip assembly. Preparing a ceramic base having external electrodes formed on opposite side surfaces and having semiconductor electrical characteristics, and continuously supplying;
Forming a circular cross-section metal lead wire continuously supplied in a reel form into a curve using a carrier tape and maintaining the metal lead wire in contact with the ceramic-based external electrode When,
Bonding the ceramic-based external electrode maintained in contact with the metal lead wire with an electrically conductive bonding means;
After the external electrode and the lead wire are bonded and electrically connected by the electrically conductive bonding means, the metal lead wire is cut mechanically and electrically by cutting the portion formed in the curve of the metal lead wire. Separating into
Dipping and sealing the ceramic base, the external electrode, the electrically conductive bonding means and the metal lead wire with a liquid insulating coating adhesive so that the other end of the metal lead wire is exposed to the outside;
Curing the insulating coating adhesive to form a solid insulating coating layer; and a method of manufacturing a ceramic chip assembly.

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