JPH11307345A - Inductance element and radio terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity and to improve a Q value, by forming a conduction film on a substrate, forming grooves on it, forming an inductance component, and installing sheet-like or board-like terminal parts on both ends of the substrate. SOLUTION: A conduction film 12 is formed on a substrate 11 by a plating method and a sputtering method. Grooves 13 are formed on the substrate 11 and the conduction film 12 with an inductance component by using laser beams and the like or executing selective etching. Then, a protection material 14 is applied on the substrate 11, the conduction film 12 and the grooves 13. The board-like or sheet-like terminal parts 15 and 16 formed of conduction materials arc jointed on the end faces of the substrate 11. The terminal parts 15 and 16 are jointed with the substrate 11 by using conduction adhesive or by ultrasonic waves and welding. Thus, a small inductance element whose productivity is high and which has a high Q value is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductance element and a radio terminal device which are used for electronic equipment such as mobile communication, and particularly suitably used for high frequency circuits and the like.

[0002]

2. Description of the Related Art FIG. 15 is a side view showing a conventional inductance element. In FIG. 15, reference numeral 1 denotes a square-pillar or cylindrical base, 2 denotes a conductive film formed on the base 1, 3 denotes a groove provided in the conductive film 2, and 4 denotes a stacked layer on the conductive film 3 Protected material.

[0003] Such electronic components are adjusted to predetermined characteristics by adjusting the interval between the grooves 3 and the like.

A prior example is disclosed in Japanese Patent Application Laid-Open No. 7-307201.
JP, JP-A-7-297033, JP-A-5-1
JP-A-29133, JP-A-1-238003, JP-A-57-117636, JP-A-5-29925
No. 0, Japanese Unexamined Patent Publication No. 7-297033, and the like.

[0005]

However, in the above configuration, although the inductance element can obtain a certain Q value, the size and performance of electronic devices such as portable radio devices have been improved recently. Alternatively, when it is required to reduce the amount of electric power used, sufficient characteristics cannot be obtained with the above-described inductance element.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a small-sized (high Q value) inductance element and a wireless terminal device with good productivity, small loss and low loss.

[0007]

According to the present invention, a conductive film is formed on a base, and a groove is formed in the conductive film to form an inductance component. A plate-shaped terminal portion is provided.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 comprises a base,
A conductive film provided on the base, a groove provided in the conductive film, a pair of terminal portions attached to an end surface of the base so as to sandwich the base, and provided on the base. Provided with a protective material provided, and as the terminal portion, a conductive plate-shaped or sheet-shaped member is used, and the base and the protective material are sandwiched between the terminal portions, thereby improving productivity. And a high Q value can be obtained.

According to a second aspect of the present invention, in the first aspect, the Q value can be further improved because the joint portion with the terminal portion of the base is only at the end face of the base.

According to a third aspect of the present invention, in the first and second aspects, the protective material for covering the groove is formed of an electrodeposition film, so that a thin and reliable element can be protected. Since a protective material can be formed on the element, productivity is improved.

According to a fourth aspect of the present invention, in the first to third aspects, the cross-sectional area of the base is made smaller than the area of the terminal, and a space between the outer end of the terminal and the surface of the base is provided. By providing the gap, the terminal portion can be formed with high precision, so that the width and height of the element can be made uniform even if a slight dimensional error occurs in the base.

According to a fifth aspect of the present invention, since the protective member is provided in the gap in the fourth aspect, the protection member can be prevented from protruding, and the mountability can be improved.

According to a sixth aspect of the present invention, the terminal can have a certain degree of strength by setting the minimum thickness of the terminal to 0.08 mm or more in the first to fifth aspects. Can be easily handled.

According to a seventh aspect of the present invention, in the first to sixth aspects, the terminal is provided with an external contact portion protruding from other portions, and a portion other than the external contact portion is covered with a protective material. The weather resistance can be improved, and the element can have directionality.

The invention according to claim 8 is the invention according to claims 1 to 7, wherein the base has a prismatic shape and the terminal portion has a rectangular plate shape, so that when the device is mounted on a substrate, rolling of the element or the like occurs. In addition, the mountability can be improved, and the shape of the base is simplified, which is very advantageous in terms of cost and manufacturing.

According to a ninth aspect of the present invention, in the first to eighth aspects, by lowering the surface roughness of the conductive film to 1 μm or less, a further decrease in the Q value can be prevented. Obtainable.

According to a tenth aspect of the present invention, in the first to eighth aspects, by lowering the surface roughness of the base to 0.5 μm or less, it is possible to further prevent a decrease in the Q value.
An element having a value can be obtained.

According to an eleventh aspect of the present invention, when the length L1, the width L2, and the height L3 in the first to eighth aspects, L1 = 0.5 to 2.1 mm L2 = 0.2 to 1.0. By having a size of 5 mm L3 = 0.2 to 1.5 mm, a small circuit board can be formed which is excellent in mountability because it is small and hard to cause element breakage and the like.

According to a twelfth aspect of the present invention, there is provided a base having a prismatic body having a substantially square cross section, a conductive film provided on the base, and a conductive film provided on the conductive film and having a side surface of the base. A spiral groove provided, a pair of square terminal portions provided on both end surfaces of the base, and a protection material provided on a side surface of the base to cover the groove, The terminal portion is formed of a plate or a sheet, and is provided only on the end face of the base, so that productivity can be improved, a high Q value can be obtained, and furthermore, mounting property and The weather resistance can be improved.

According to a thirteenth aspect of the present invention, a columnar base is formed, a conductive film is formed on the base, and a groove is formed in the base so as to remove a part of the conductive film. Attach plate or sheet terminals to both ends of the base,
After that, by providing a protective material so as to cover at least the groove, productivity is improved, and a high Q value can be obtained.

According to a fourteenth aspect of the present invention, in the thirteenth aspect, the protective material is an electrodeposition film formed by an electrodeposition method.
Thin and reliable protection of the elements can be performed, and moreover, protective materials can be formed on many elements at once, so that productivity is improved.

According to a fifteenth aspect of the present invention, there is provided a display means, a conversion means for converting at least one of a data signal and a voice signal into a transmission signal or a reception signal into at least one of a data signal and a voice signal, and An antenna for transmitting and receiving a signal and the reception signal, and a wireless terminal device including control means for controlling each unit, comprising: a transmission circuit;
13. At least one of a filter circuit, an antenna unit, a peripheral circuit of a matching circuit for each stage, and the like.
By using the described inductance element, the substrate and the like inside the device can be miniaturized, and since the Q value is high, the loss becomes very small, so that the power can be reduced and the operation can be performed for a long time. be able to.

Hereinafter, embodiments of the inductance element and the wireless terminal device according to the present invention will be described.

1 and 2 are a perspective view and a side sectional view, respectively, showing an inductance element according to an embodiment of the present invention.

In FIG. 1, reference numeral 11 denotes a base which is formed by pressing an insulating material or the like by an extrusion method or the like.
Reference numeral 2 denotes a conductive film provided on the base 11.
2 is formed on the base 11 by an evaporation method such as a plating method or a sputtering method.

Reference numeral 13 denotes a groove provided on the base 11 and the conductive film 12. The groove 13 is formed by irradiating the conductive film 12 with a laser beam or the like, or is mechanically formed by applying a grindstone or the like to the conductive film 12. Or by selective etching using a resist or the like.

Reference numeral 14 denotes a protective material applied to a portion of the base 11 and the conductive film 12 where the groove 13 is provided. Reference numerals 15 and 16 denote terminals respectively attached on the end face of the base 11 (preferably only on the end face). The base 11 is sandwiched between the terminal 15 and the terminal 16. That is, the base 1
1 is connected to the bases 11 and 16
Of the base 11 and the terminal portions 15 and 16
Is basically non-contact.

A feature of the present invention is that the terminal portions 15 and 16 are made of a plate or a sheet made of a conductive material. With such a configuration, the terminal portions 15, 16
The process is much simpler than that of using a plating film or the like, and an inductance element that obtains a high Q value can be obtained. As a specific constituent material of the terminal portions 15 and 16, a conductive ceramic material, a resin material, a metal material, or the like can be used. In particular, a metal material is advantageous in workability and cost. As the metal material, F
A simple substance such as e, Cu, Ag, or Au, an alloy thereof, or a composite alloy such as stainless steel is used. Among these metallic materials, it is preferable to use Cu or an alloy of Cu and other components in consideration of cost and the like and workability.

The connection between the terminal portions 15 and 16 and the base 11 is as follows.
The bonding is performed by using a conductive adhesive (high-temperature solder or the like), ultrasonic waves, welding, or the like.

Further, the inductance element of the present embodiment has a practical frequency band of 1 to 6 GHz, which corresponds to a high frequency range, and has a very high Q value (35 or more).
Length L1, width L2, height L3 of the inductance element
Is preferably as follows.

L1 = 0.5 to 2.1 mm (preferably 0.6 to 1.6 mm) L2 = 0.2 to 1.5 mm (preferably 0.3 to 0.8)
mm) L3 = 0.2 to 1.5 mm (preferably 0.3 to 0.8)
(Note that the dimensional error of each of L1, L2, and L3 is 0.3 mm.)
It is preferably equal to or less than 02 mm. If L1 is less than 0.5 mm, the required inductance cannot be obtained. Further, if L1 exceeds 2.1 mm, the element itself becomes large, and it is not possible to reduce the size of a circuit board or the like on which an electronic circuit or the like is formed (hereinafter abbreviated as a circuit board or the like). It is not possible to reduce the size of an electronic device or the like on which a circuit board or the like is mounted. If each of L2 and L3 is 0.2 mm or less, the mechanical strength of the element itself becomes too weak, and the element may break when mounted on a circuit board or the like by a mounting apparatus or the like. is there. On the other hand, if L2 and L3 are 1.5 mm or more, the elements become too large, and it is not possible to reduce the size of the circuit board or the like and, consequently, the size of the device.

With respect to the inductance element configured as described above, each part will be described in detail below.

First, the shape of the base 11 will be described.
The base 11 is preferably formed in a prismatic or cylindrical shape. By forming the base 11 in a prismatic shape as shown in FIGS. 1 and 2, the mountability can be improved, and the rolling of the element can be prevented. And the like. In addition, among the rectangular bases, the base 11 is particularly preferably formed in a square pillar shape, which greatly facilitates the mounting and the positioning of the element on the circuit board. In addition, it is more preferable that the bottom surface is a rectangular parallelepiped having a square shape, so that the mountability and the like can be further improved. Furthermore, base 1
Since the structure is made very simple by making 1 a prismatic shape, productivity is good and cost is very advantageous.

When the base 11 is formed in a cylindrical shape, a conductive film 12 is formed on the base 11 as described later, and when a groove is formed in the conductive film 12 by laser processing or the like, the conductive film The depth of the groove and the like can be formed with high accuracy, and variations in characteristics can be suppressed.

Next, the chamfering of the base 11 will be described with reference to FIG. FIG. 3 is a perspective view showing the base 11.

The corners 11b and 11c of the base 11 are chamfered, and the radius of curvature R1 of each of the chamfered corners 11b and 11c and the radius of curvature R2 of the corner 11a.
Is preferably formed as follows.

0.03 <R1 <0.15 (mm) 0.01 <R2 (mm) If R1 is 0.03 mm or less, the corner portions 11b and 11c
Because of the sharp point, the corners 11b and 11c may be chipped by a slight impact or the like, and the chipping may cause deterioration of characteristics or the like. When R1 is 0.15 mm or more, the corner 11
Since b and 11c are too round, the above-mentioned Manhattan phenomenon is likely to occur, which causes a problem. Furthermore, when R2 is 0.
When the thickness is less than or equal to 01 mm, burrs and the like are likely to occur at the corners 11a, and the thickness of the conductive film 12, which largely affects the characteristics of the element, may be significantly different between the corners 11f and the flat portion,
Variation in element characteristics increases.

Next, the constituent materials of the base 11 will be described. It is preferable to satisfy the following characteristics as a constituent material of the base 11.

Volume resistivity: 10 ¹³ Ωm or more (preferably 10 ¹⁴ Ωm or more) Thermal expansion coefficient: 5 × 10 ⁻⁴ / ° C. or less (preferably 2 × 10 Ω / m)
⁻⁵ / ° C. or less) [Coefficient of thermal expansion at 20 ° C. to 500 ° C.] Relative permittivity: 12 or less at 1 MHz (preferably 10
Bending strength: 1300 kg / cm ² or more (preferably 20
Density: ^{2 to 5} g / cm ³ (preferably ³ to 4 g / cm ³ ) When the constituent material of the base 11 has a volume resistivity of 10 ¹³ Ωm or less, the conductive material 12 and the base 11 Also, a current starts to flow in a predetermined manner, so that a parallel circuit is formed, and the self-resonant frequency f0 and the Q value decrease, which is not suitable for a high-frequency element.

If the coefficient of thermal expansion is 5 × 10 ⁻⁴ / ° C. or more, cracks may occur in the base 11 due to heat shock or the like. That is, when the thermal expansion coefficient is 5 × 10 ⁻⁴ / ° C. or more, the base 11 is locally heated to a high temperature because a laser beam or a grindstone is used when forming the groove 13 as described above. Although cracks and the like may occur in 11, the occurrence of cracks and the like can be greatly suppressed by having the above-described coefficient of thermal expansion.

If the dielectric constant is 12 or more at 1 MHz, the self-resonant frequency f0 and the Q value become low, which is not suitable for a high-frequency device.

When the bending strength is 1300 kg / cm ² or less, the device may be broken when mounted on a circuit board or the like by a mounting apparatus.

When the density is 2 g / cm ³ or less, the base 1
1, the water absorption rate is increased, the characteristics of the base 11 are significantly deteriorated, and the characteristics as an element are deteriorated. The density is 5 g / c
If it exceeds m ³ , the weight of the base will be heavy, and there will be a problem in mountability and the like. In particular, when the density is set within the above range, the water absorption rate is small, water hardly enters the base 11, the weight is reduced, and no problem occurs when mounting on a substrate by a chip mounter or the like.

By defining the volume resistivity, the thermal expansion coefficient, the dielectric constant, the bending strength, and the density of the base 11 as described above, the self-resonant frequency f0 and Q do not decrease. It is possible to suppress the occurrence of cracks or the like in the base 11 due to heat shock or the like, so that the defective rate can be reduced, and furthermore, the mechanical strength can be improved. Since it can be mounted on a circuit board or the like, excellent effects such as improvement in productivity can be obtained.

As a material for obtaining the above-mentioned various properties, a ceramic material containing alumina as a main component can be mentioned. However, simply using a ceramic material mainly composed of alumina cannot obtain the above-mentioned characteristics. That is,
Since the above-mentioned various characteristics vary depending on the pressing pressure, the sintering temperature, and the additives at the time of producing the base 11, the production conditions and the like must be appropriately adjusted. Specific manufacturing conditions include a pressing pressure of 2 to 5 tons when processing the base 11, a firing temperature of 1500 to 1600 ° C., and a firing time of 1 to 3 hours. Specific examples of the alumina material include Al ₂ O ₃ of 92 wt% or more, SiO ₂ of 6 wt% or less, MgO of 1.5 wt% or less, and Fe ₂ O ₃ of 0.1 wt% or less.
% Or less, and Na ₂ O of 0.3% by weight or less.

The base 11 may be made of a magnetic material such as ferrite. When the base 11 is made of a magnetic material such as ferrite, an element having high inductance (about 18 nH to 50 nH) can be formed.

Next, the surface roughness of the base 11 will be described. The surface roughness described below means the average roughness of the center line, and the roughness described in the description of the conductive film 12 is also the average roughness of the center line.

The surface roughness of the base 11 is 0.15 to 0.5 μm
m, preferably about 0.2 to 0.3 μm. FIG. 4 is a graph showing the surface roughness of the base 11 and the rate of occurrence of peeling. FIG. 4 shows the results of an experiment as described below. The base 11 and the conductive film 12 were made of alumina and copper, respectively, and samples with various surface roughnesses of the base 11 were prepared, and the conductive film 12 was formed on each sample under the same conditions. Each sample was subjected to ultrasonic cleaning, and thereafter, the surface of the conductive film 12 was observed to determine whether or not the conductive film 12 was peeled. The surface roughness of the base 11 was measured using a surface roughness measuring device (574A, manufactured by Tokyo Seimitsu Surfcom).
The one having a tip R of 5 μm was used. As can be seen from this result, if the average surface roughness is 0.15 μm or less,
The rate of occurrence of peeling of the conductive film 12 formed thereon is about 5%, and good bonding strength between the base 11 and the conductive film 12 can be obtained. Further, if the surface roughness is 0.2 μm or more, peeling of the conductive film 12 hardly occurs. Therefore, if possible, the surface roughness of the base 11 is preferably 0.2 μm or more. Since the peeling of the conductive film 12 is a major factor in deterioration of the characteristics of the element, the rate of occurrence is 5% in terms of yield and the like.
The following is preferred.

FIG. 5 is a graph showing the relationship between the frequency and the Q value with respect to the surface roughness of the base used for the inductance element according to one embodiment of the present invention. FIG. 5 shows the results of the following experiment. First, each sample of the base 11 having a surface roughness of 0.1 μm or less, the base 11 having a surface roughness of 0.2 to 0.3 μm, and the base 11 having a surface roughness of 0.5 μm or more was prepared. Then, a conductive film having the same thickness and the same material (copper) was formed on each sample. Then, in each sample, the Q value at a predetermined frequency F was measured. As can be seen from FIG. 5, the surface roughness of the base 11 is 0.5 μm.
If it is more than m, a decrease in the Q value, which is considered to be caused by the deterioration of the film structure of the conductive film 12, is observed. Particularly in the high frequency region, the Q value is significantly deteriorated. Also, the self-resonant frequency f0 (maximum value of each line) has a surface roughness of 0.5
Those of μm are shifted to the lower frequency side. Therefore, the surface roughness of the base 11 is preferably 0.5 μm or less from the viewpoint of the Q value and the surface of the self-resonant frequency f0.

As described above, judging from the results of both the adhesion strength between the conductive film 12 and the base 11, the Q value of the conductive film, and the self-resonant frequency f0, the surface roughness of the base 11 is 0.15.
μm to 0.5 μm, more preferably 0.2 μm
０．３0.3 μm is good.

In the present embodiment, the bonding strength between the conductive film 12 and the base 11 is improved by adjusting the surface roughness of the base 11.
2 to improve the adhesion strength between the conductive film 12 and the base 11 without adjusting the surface roughness by providing an intermediate layer composed of Cr alone or an alloy of Cr and another metal. Can be. Of course, when the surface roughness of the base 11 is adjusted and the intermediate layer and the conductive film 12 are laminated on the base 11, it is possible to obtain a stronger adhesion strength between the conductive film 12 and the base 11. it can.

Next, the conductive film 12 will be described. The conductive film 12 has a Q value of 35 or more for a high-frequency signal of 800 MHz or more, and has a self-resonant frequency of 1 to 6
A frequency of about GHz is preferable. Conductive film 1 having such characteristics
In order to obtain 2, it is necessary to select a material and a manufacturing method.

Hereinafter, the conductive film 12 will be specifically described. Examples of a constituent material of the conductive film 12 include conductive materials such as copper, silver, gold, and nickel. A predetermined element may be added to the material such as copper, silver, gold, and nickel to improve weather resistance and the like. Alternatively, an alloy such as a conductive material and a nonmetallic material may be used. Copper and its alloys are often used as constituent materials in terms of cost, corrosion resistance, and ease of fabrication. When copper or the like is used as the material of the conductive film 12, first, a base film is formed on the base 11 by electroless plating, and a predetermined copper film is formed on the base film by electrolytic plating. The conductive film 12 is formed. Further, when the conductive film 12 is formed of an alloy or the like, it is preferable to form the conductive film 12 by a sputtering method or a vapor deposition method.

Further, as in the present embodiment, when the conductive film 12 is made of, for example, copper or the like and the film thickness is increased to suppress self-heating, the width K1 of the groove 13 formed in the conductive film 12 is reduced. The width K2 of the conductive film 12 between the grooves 13 preferably has the following relationship.

20 μm>K1> 15 μm 200 μm>K2> 100 μm In particular, as described above, the length L1, width L2, and height L3 are L1 = 0.5 to 2.1 mm (preferably 0.6 to 1.6).
mm) L2 = 0.2 to 1.5 mm (preferably 0.3 to 0.8)
mm) L3 = 0.2 to 1.5 mm (preferably 0.3 to 0.8)
(Note that the dimensional error of each of L1, L2, and L3 is 0.3 mm.)
It is preferably equal to or less than 02 mm. In the case of the inductance element described in (1), by setting the above K1 and K2 within the above ranges, the electric resistance can be reduced and the groove 13 formed in the conductive film 12 can be formed with high accuracy. In addition, when the thickness of the conductive film 12 is further increased, the groove 13 can be surely formed.

The conductive film 12 may have a single-layer structure, but may have a multilayer structure. That is, a plurality of conductive films having different constituent materials may be stacked. For example, first, a copper film is formed on the base 11, and then a metal film having good weather resistance (such as nickel) is laminated thereon, so that corrosion of copper, which is somewhat problematic in weather resistance, can be prevented. .

Examples of the method for forming the conductive film 12 include a plating method (such as an electrolytic plating method and an electroless plating method), a sputtering method, and a vapor deposition method. Among these forming methods,
A plating method with good mass productivity and small variations in film thickness is often used.

The surface roughness of the conductive film 12 is preferably 1 μm or less, more preferably 0.2 μm or less. When the surface roughness of the conductive film 12 exceeds 1 μm, the Q value at high frequencies decreases due to the skin effect. FIG. 6 is a graph showing the relationship between the frequency and the Q value with respect to the surface roughness of the conductive film used for the inductance element according to one embodiment of the present invention. FIG. 6 was derived through the following experiment. First, a conductive film 12 made of copper is formed on a base 11 having the same size and the same material with the same surface roughness while changing the surface roughness. Was measured. As can be seen from FIG. 6, when the surface roughness of the conductive film 12 is 1 μm or more, the Q value in the high frequency region is low. Furthermore, if the surface roughness of the conductive film 12 is 0.2 μm or less, Q
It can be seen that the value is very high.

As described above, the surface roughness of the conductive film 12 is 1.
The thickness is preferably 0 μm or less, and more preferably 0.2 μm or less, the skin effect of the conductive film 12 can be reduced, and the Q value particularly at high frequencies can be improved.

Further, the adhesion strength between the conductive film 12 and the base 11 is as follows:
After leaving the base 11 on which the conductive film 12 is formed at a temperature of 400 ° C. for a few seconds, it is preferable that the conductive film 12 be separated from the base 11 by a degree or more. When the element is mounted on a substrate or the like, a temperature of 200 ° C. or more may be applied to the element due to self-heating or heat from other members. Therefore, the conductive film 12 from the base 11 at 400 ° C.
If the adhesion strength is such that no peeling occurs, even if heat is applied to the element, the characteristics of the element do not deteriorate.

Next, the protective member 14 will be described. As the protective material 14, an organic material having excellent weather resistance, for example, an insulating material such as an epoxy resin or an electrodeposition film is used.
Further, it is preferable that the protective material 14 has a transparency such that the condition of the groove 13 can be observed. Further protective material 14
It is preferable to have a predetermined color while maintaining transparency. By coloring the protective material 14 with a color such as red, blue, or green, which is different from the conductive film 12 and the terminal portions 15 and 16, it is possible to distinguish each element portion, and to easily inspect each element portion. . In addition, by changing the color of the protective material 14 depending on the size, characteristics, product number, and the like of the element, it is possible to reduce errors such as mounting an element having a different characteristic, product number, and the like on an erroneous portion.

In particular, when the protective material 14 is formed of an electrodeposited film, the insulating material can be very thin and the insulation can be secured, and the heat resistance can be improved. That is, when the method of applying an epoxy resin, a resist, or the like is applied, a portion of the protective material 14 rises greatly, and when mounted on a circuit board or the like, a gap may be generated between the terminal portion of the element and the wiring of the circuit board. In some cases, sufficient electrical bonding cannot be performed. However, by forming the protective material 14 with an electrodeposition film, a thin and uniform protective material 14 can be formed. In addition, the gap between the terminal portion and the wiring becomes very small, and the electrical connection between the wiring and the terminal of the substrate can be sufficiently performed.

Further, in the method of applying a resist or the like, each element must be applied using a tape or the like, so that the number of steps is increased, productivity is not improved, and manufacturing cost is reduced. Although it is not possible, as in the present embodiment, by forming the protective material 14 with an electrodeposition film, the protective material 14 can be provided to many elements at once, so that the productivity is reduced even if it is improved. Can be done.

As a specific constituent material of the protective material 14, an electrodeposition resin film made of at least one resin material such as an acrylic resin, an epoxy resin, a fluorine resin, a urethane resin, and a polyimide resin is used. It is configured. In the case where the protective material 14 is formed of an electrodeposited film, and when either the cation type or the anion type is selected, the constituent material of the conductive film 12, the constituent material of the electrodeposited film, and the usage of the inductance element are used. It is preferable to determine in consideration of the above. The protective material 14 may be formed by laminating electrodeposited films made of different materials, or may be formed by laminating the same material. Further, a plurality of electrodeposited films may be stacked on the groove 13 in parallel. It may be provided.

When the protective member 14 is formed of an electrodeposited film, the protective member 14 preferably has a thickness of several tens of microns and a withstand voltage of 20 V or more, and has a melting point of 183 ° C., which is the melting point of solder.
It is preferable to use a material having characteristics of not burning or evaporating. In the case where the protective material 14 is softened at 183 ° C., no problem occurs.

As shown in FIG. 7A, it is preferable that the protective material 14 made of an electrodeposition film be provided so as to cover both the conductive film 12 and at least a part of the base 11. By providing the protective material 14 in this manner, the conductive film 12 can be substantially covered, and the probability of contact between the conductive film 12 and outside air can be extremely reduced.
2 can be prevented, current leakage, and the like can be prevented. FIG.
In the case where the protective material 14 is provided only on the conductive film 12 as shown in (b), there is a high possibility that the corner 12z of the conductive film 12 is exposed, which may cause corrosion of the conductive film 12.

Therefore, as shown in FIG.
By forming the second corner 12z so as to cover at least a part of the base 11 with the protective material 14, reliable protection of the conductive film 12 can be covered.

As shown in FIG. 7A, a part 14 of the protective material 14 formed on the outer corner 12p of the conductive film 12 is formed.
It is preferable that z is thicker than other portions. By increasing the thickness of the portion 14z, it is possible to prevent the corner portion 12p from being discharged with other portions, and to prevent deterioration of characteristics as an inductance element.

In some cases, it is important for an inductance element used for a special purpose to have an adhesion strength between the conductive film 12 and the protective material. In this case, it is preferable to roughen the surface of the conductive film 12 by chemical etching, and to provide a protective material 14 made of an electrodeposition film on the roughened surface. As previously mentioned,
If the surface of the conductive film 12 is roughened, there is a risk of lowering the Q value.
In some cases, it is important to improve the adhesion strength between the conductive film 12 and the conductive film 12.
Must be determined appropriately.

When the conductive film 12 is made of a material containing copper, the protective material 14 which is an electrodeposition film may be formed with an uneven film thickness. A metal film such as Ni is formed thereon, and a protective material 1 is formed on the metal film.
4 may be formed.

Next, a method of forming the protective member 14 composed of an electrodeposition film will be described. As shown in FIG. 8, reference numeral 100 denotes a container. The container 100 contains a solution 101 obtained by mixing water, an electrodeposition resin, an adjusting agent such as a pH adjusting agent, and other additives. 102 is an electrode plate, 103 is an inductance element, 104 and 105 are holding members, respectively, and the holding members 104 and 105 are provided with holes into which both ends of the inductance element 103 fit. The holding member 105 is provided with an energizing section 6, and the energizing section 6 is in contact with the inductance element 103.

When a predetermined voltage is applied to the electrode plate 102 and the current-carrying portion 106, an electrodeposition film is formed on a portion of the inductance element 103 except for both ends. This is because the terminals 15 and 16 of the inductance element 103 are connected to the holding members 104 and 1.
This is because they have entered the liquid crystal 05 and are not in contact with the solution 101 much. In the present embodiment, the holding member 1
Although the terminal portions 15 and 16 are inserted into the terminal portions 04 and 105, another mask member such as a photoresist may be provided on the terminal portions 15 and 16.

As described above, the protective material 1 composed of the electrodeposited film
After manufacturing the inductance element having No. 4, it is preferable to apply heat treatment to the element. By this heat treatment,
The surface of the protection member 14 becomes gentle, the surface roughness becomes small, and the protection member 14 is surely covered. In addition, when heat treatment is performed, the thickness of the protective material 14 at the corners of the conductive film 12 may be reduced. In this case, insulating particles (for example, metal oxide) are added to the solution 101. By mixing the insulating particles in the protective material 14 made of an electrodeposited film, the thickness of the protective material 14 at the corners of the conductive film 12 can be reduced.

Next, the terminals 15 and 16 will be described.
As described above, the terminal portions 15 and 16 are made of a plate or sheet made of a conductive material.
The base 11 is sandwiched between the terminal 5 and the terminal portion 16. At this time, the terminals 15 and 16 may be coated with a material having high corrosion resistance, such as Ni, Ti, or Cr, in order to improve the weather resistance. A conductive material such as solder may be coated.
16 and may be coated with a material that improves the connectivity with the circuit board.

The terminal portions 15 and 16 determine the width L2 and the height L3 of the inductance element. That is, as shown in FIG. 9, the width and height of the terminal portions 15 and 16 correspond to the width L2 and height L3 of the inductance element. As can be seen from FIG. 9, the cross-sectional area of the base 11 is configured to be slightly smaller than the cross-sectional areas of the terminal portions 15 and 16, and the base 11 has a size that does not protrude from the terminal portions 15 and 16. doing. Further, as shown in FIG. 9, when the terminals 15 and 16 are attached to the base 11, the distances t1 and t2 between the surface of the base 11 and the outer end surfaces of the terminals 15 and 16 respectively satisfy the following relationships. Things are preferred.

0 <t1 ÷ L2 <0.1 0 <t2 ÷ L3 <0.1 By satisfying the above conditions, a high inductance and a high Q value can be realized without reducing the size of the base 11. In addition, the protective member 14 can be provided in the gap between t1 and t2, and good mounting properties can be obtained without protruding from the outer ends of the terminal portions 15 and 16.

When L2 = L3, it is preferable that t2 = t1. Further, as shown in FIG. 2, the heights Z1 and Z2 of the terminal portions 15, 16 preferably satisfy the following conditions.

| Z1-Z2 | ≦ 80 μm (preferably 5
0 μm) The height difference between Z1 and Z2 is 80 μm (preferably 50 μm).
m or less), when the element is mounted on a board and attached to a circuit board or the like with solder or the like, the element is pulled to one end by the surface tension of the solder or the like, and the element stands up. The probability of occurrence is very high. This Manhattan phenomenon is shown in FIG. As shown in FIG. 10, an inductance element is arranged on a substrate 200, and solders 201 and 202 are provided between each of the terminal portions 15 and 16 and the substrate 200. The solders 201 and 202 are melted by reflow or the like. And solder 201, 20
Due to the difference in the application amount of each of No. 2 and the difference in the melting point due to the difference in the material, the surface tension of the melted solders 201 and 202 differs between the terminal portions 15 and 16, and as a result, as shown in FIG. Around the terminal part of
The inductance element rises. Z1 and Z2
When the height difference exceeds 80 μm (preferably 50 μm or less), the elements are disposed on the substrate 200 in an inclined state, and the element is promoted. In addition, the Manhattan phenomenon occurs remarkably particularly in small and lightweight chip-type electronic components (including a chip-type inductance element), and one of the causes of the Manhattan phenomenon is the difference in height between the terminal portions 15 and 16. The device is tilted by the substrate 2
It is noted that they are arranged at 00. As a result, Z1 and Z
By forming the base 11 by molding or the like so that the difference in height between the two would be 80 μm or less (preferably 50 μm or less), the occurrence of the Manhattan phenomenon could be greatly suppressed. By setting the difference between the heights of Z1 and Z2 to 50 μm or less, the occurrence of the Manhattan phenomenon can be substantially suppressed.

Next, the thickness of the terminal portions 15 and 16 will be described. The thickness P of each of the terminal portions 15 and 16 shown in FIG.
2, P1 preferably satisfies the following conditions.

P1 ÷ L1 <0.12 P2 ÷ L1 <0.12 By satisfying the above conditions, the length of the base 11 can be increased, and accordingly, the inductance can be increased. , Q value can be improved. Even when P1 and P2 are within the above ranges, it is not preferable to set the thickness of the terminal portions 15 and 16 to 0.08 mm or less in consideration of the strength and ease of handling. Accordingly, L1 becomes smaller. For example, when L1 is 0.6 mm, P1 and P2 become 0.072 mm, which is thinner than 0.08 mm. The thickness is preferably set to 0.08 mm even if the Q value is slightly reduced.

A method of manufacturing the inductance element having the above-described configuration will be described below.

First, the base 11 is manufactured by pressing or extruding an insulating material such as alumina. Next, a conductive film 12 is formed on the entire base 11 by a plating method, a sputtering method, or the like. Next, a spiral groove 13 is formed in the base 11 on which the conductive film 12 is formed. The groove 13 is formed by laser processing or cutting. Since the laser processing has very high productivity, the laser processing will be described below. First, the base 11 is attached to a rotating device, the base 11 is rotated, and the base 11 is irradiated with a laser to remove both the conductive film 12 and the base 11, thereby forming a spiral groove. The laser at this time is a YAG laser,
An excimer laser, a carbon dioxide laser, or the like can be used, and the base 11 is irradiated with the laser light by narrowing the laser light with a lens or the like. Further, the depth and the like of the groove 13 can be adjusted by adjusting the power of the laser, and the width and the like of the groove 13 can be adjusted by exchanging a lens when narrowing down the laser beam. Since the laser absorptivity varies depending on the constituent material of the conductive film 12 and the like, it is preferable to appropriately select the type of laser (laser wavelength) depending on the constituent material of the conductive film 12.

After the grooves 13 are formed, the terminal portions 15, 1 formed into a plate-like body or a sheet-like body are provided at both ends of the base 11.
When the terminal portions 15 and 16 are bonded to the base 11 at this time, a conductive bonding material such as high-temperature solder is used. In addition, as another joining method, a terminal portion 15 made of the same material as the conductive film 12 formed on the end face of the base 11,
The terminal portions 15 and 16 can be joined to the base 11 by welding or the like by bringing the base portions 11 into contact with each other.

At this point, the product is completed. However, as described above, the protective material 14 is provided by applying an epoxy resin or the like or forming an electrodeposition film to improve the weather resistance of the entire device. .

Next, a second embodiment will be described.
FIG. 11 is a side view of the inductance element according to the second embodiment of the present invention.

In FIG. 11, the same reference numerals as those in FIGS. 1 and 2 denote the same members. The difference between the inductance element shown in FIG. 11 and the inductance element shown in FIG.
There is a difference between the shapes of Nos. 5 and 16 and the range in which the protective material 14 is formed.

The inductance element shown in FIG.
As shown in FIG. 2, two opposite sides of the terminal portions 15 and 16 are formed longer than the other sides. That is, FIG.
In FIG. 7, the portions where the hatched portions are longer than the terminal portions 15 and 16 shown in FIG.

Further, the protection member 14 is provided on the terminal portions 15 and 16, and only the external contact portion 700 is not formed with the protection member 14.

According to such a configuration, directionality exists when the inductance element is mounted. However, since the protection member 14 can be provided widely, the weather resistance of the element can be improved.

Although the present embodiment has been described with reference to an inductance element, the same effect can be obtained with an electronic component in which a conductive film is formed on a base made of an insulating material.

FIGS. 13 and 14 are a perspective view and a block diagram, respectively, showing a wireless terminal device according to an embodiment of the present invention. 13 and 14, reference numeral 29 denotes a microphone for converting a voice into a voice signal, 30 denotes a speaker for converting a voice signal into a voice, 31 denotes an operation unit including dial buttons and the like, and 32 denotes a display unit for displaying an incoming call and the like. 33, an antenna; and 34, a transmitting unit for demodulating an audio signal from the microphone 29 and converting it into a transmission signal. The transmission signal produced by the transmission unit 34 is emitted to the outside through the antenna. A receiving unit 35 converts a received signal received by the antenna into an audio signal, and the audio signal created by the receiving unit 35 is transmitted to the speaker 3.
At 0, it is converted to voice. 36 is a transmitting unit 34 and a receiving unit 3
5, a control unit for controlling the operation unit 31 and the display unit 32;

Hereinafter, an example of the operation will be described. First, when there is an incoming call, the receiving unit 35 sends the
The control unit 36 displays a predetermined character or the like on the display unit 32 based on the incoming signal,
Further, when a button or the like for receiving an incoming call is pressed from the operation unit 31, a signal is sent to the control unit 36, and the control unit 36
Set each part to the incoming call mode. That is, the signal received by the antenna 33 is converted into an audio signal by the receiving unit 35, and the audio signal is output from the speaker 30 as audio.
The voice input from the microphone 29 is converted into a voice signal, and is transmitted to the outside via the transmitting unit 34 and the antenna 33.

Next, the case of transmitting a call will be described. First, when transmitting a signal, a signal indicating that the signal is transmitted from the operation unit 31 is input to the control unit 36. Subsequently, when a signal corresponding to the telephone number is transmitted from the operation unit 31 to the control unit 36, the control unit 36 transmits a signal corresponding to the telephone number from the antenna 33 via the transmission unit 34. When communication with the other party is established by the transmission signal, a signal to that effect is sent to the control unit 36 through the reception unit 35 via the antenna 33, and the control unit 36 sets each unit to the transmission mode. That is, the signal received by the antenna 33 is converted into an audio signal by the receiving unit 35, the audio signal is output as audio from the speaker 30, and the audio input from the microphone 29 is converted into an audio signal, Through the antenna 33 to the outside.

In the present embodiment, an example in which voice is transmitted and received has been described. However, the present invention is not limited to voice, and a similar effect can be obtained for a device that transmits or receives data other than voice such as character data. Can be obtained.

The inductance element described above (FIG. 1)
12 to FIG. 12) have high Q values such as a transmitting circuit, a filter circuit, an antenna section, and a peripheral section of a matching circuit with each stage.
Are used in at least one of the locations that require the same, and the number is about several to forty in one wireless terminal device. By using the inductance element as described above, the size of the substrate and the like inside the device can be reduced, and the Q value is high, so that the loss becomes very small, so that the power can be reduced and the operation for a long time can be performed. It can be carried out.

[0096]

According to the present invention, a conductive film is formed on a base,
A groove is formed in the conductive film to form an inductance component, and thereafter, a sheet-shaped or plate-shaped terminal portion is provided at both ends of the base, so that productivity is improved, and a small and high Q value is obtained. be able to.

Also, by mounting the above-described inductance element in the wireless terminal device, it is possible to reduce the size of the substrate and the like inside the device, and furthermore, since the Q value is high, the loss is very small, so that the power can be reduced. And a long-time operation can be performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an inductance element according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing an inductance element according to an embodiment of the present invention.

FIG. 3 is a perspective view of a base used for the inductance element according to the embodiment of the present invention;

FIG. 4 is a graph showing the surface roughness and the rate of occurrence of peeling of a base used for an inductance element according to an embodiment of the present invention.

FIG. 5 is a graph showing a relationship between a frequency and a Q value with respect to a surface roughness of a base used for an inductance element according to an embodiment of the present invention.

FIG. 6 shows a relationship between the frequency and Q with respect to the surface roughness of a conductive film used for an inductance element according to an embodiment of the present invention.
Graph showing value relationships

FIG. 7 is an enlarged sectional view of a portion provided with a protective material for an inductance element according to an embodiment of the present invention.

FIG. 8 is a view showing a step of providing a protective material for an inductance element in one embodiment of the present invention.

FIG. 9 is a front view of a terminal portion of the inductance element according to the embodiment of the present invention.

FIG. 10 is a diagram showing the Manhattan phenomenon.

FIG. 11 is a side view of the inductance element according to the second embodiment of the present invention.

FIG. 12 is a front view of a terminal portion of an inductance element according to a second embodiment of the present invention.

FIG. 13 is a perspective view showing a wireless terminal device according to one embodiment of the present invention;

FIG. 14 is a block diagram showing a wireless terminal device according to an embodiment of the present invention;

FIG. 15 is a side view showing a conventional inductance element.

[Explanation of symbols]

 Reference Signs List 11 base 12 conductive film 13 groove 14 protective material 15, 16 terminal unit 30 speaker 31 operation unit 32 display unit 33 antenna 34 transmission unit 35 reception unit 36 control unit 700 external contact unit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Iso ▲ Saki ▼ Kenzo 1006, Oaza Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (15)

[Claims] 1. A base, a conductive film provided on the base, a groove provided in the conductive film, and a pair of terminals mounted on an end face of the base so as to sandwich the base. And a protective material provided on the base, and a conductive plate or sheet is used as the terminal, and the base and the protective material are used at the terminal. An inductance element characterized by being sandwiched. 2. The inductance element according to claim 1, wherein a joint portion of the base with the terminal portion is only an end face of the base. 3. The inductance element according to claim 1, wherein the protective material covering the groove is an electrodeposition film. 4. The base according to claim 1, wherein a cross-sectional area of the base is smaller than an area of the terminal, and a gap is provided between an outer end of the terminal and a surface of the base. One of three
The inductance element described. 5. The inductance element according to claim 4, wherein a protective material is provided in the gap. 6. The inductance element according to claim 1, wherein the minimum thickness of the terminal portion is 0.08 mm or more. 7. The inductance element according to claim 1, wherein an external contact portion protruding from other portions is provided on the terminal portion, and a portion other than the external contact portion is covered with a protective material. 8. The inductance element according to claim 1, wherein the base has a prismatic shape, and the terminal portion has a rectangular plate shape. 9. The inductance element according to claim 1, wherein the surface roughness of the conductive film is 1 μm or less. 10. The inductance element according to claim 1, wherein the surface roughness of the base is 0.5 μm or less. 11. When a length L1, a width L2, and a height L3 are set, a size of L1 = 0.5 to 2.1 mm L2 = 0.2 to 1.5 mm L3 = 0.2 to 1.5 mm The inductance element according to claim 1, wherein the inductance element has: 12. A base having a prismatic body having a substantially square cross section, a conductive film provided on the base, and a spiral-shaped provided on the conductive film and provided on a side surface of the base. A groove, a pair of square terminal portions provided on both end surfaces of the base, and a protective material provided on a side surface of the base so as to cover the groove, wherein the terminal portion has a plate shape. An inductance element comprising a body or a sheet-like body and provided only on an end face of the base. 13. A columnar base is formed, a conductive film is formed on the base, a groove is formed in the base so as to remove a part of the conductive film, and plates are formed at both ends of the base. A method of manufacturing an inductance element, comprising attaching a terminal portion of a shape or a sheet, and thereafter providing a protective material so as to cover at least the groove. 14. The method according to claim 13, wherein the protective material is an electrodeposition film formed by an electrodeposition method. 15. A display means, conversion means for converting at least one of a data signal and an audio signal into a transmission signal or converting a reception signal into at least one of a data signal and an audio signal, and converting the transmission signal and the reception signal. 13. A wireless terminal device comprising an antenna for transmitting and receiving and control means for controlling each part, wherein at least one of a transmitting circuit, a filter circuit, an antenna part and a peripheral part of a matching circuit for each stage is provided. A wireless terminal device using the inductance element according to claim 1.