JP2000030940A - Thin film electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film impedance element which can maintain high impedance characteristic from a low frequency band of several 10 MHz to a high frequency band of several GHz. SOLUTION: In a zigzag structure where inner conductors 3, 6 are three- dimensionally extended, the inner conductor 6 connected with an external electrode which is spread and formed on one side conductor leading-out part 2a is extended to an external electrode which is spread and formed on the other side conductor leading-out part 2b without returning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film electronic component, and more particularly to an electronic component suitable for a thin-film impedance element and an inductance element having a high resonance frequency and high frequency characteristics up to high frequencies.

[0002]

2. Description of the Related Art Generally, an LC filter and an impedance element, particularly, a surface-mounted type multilayer impedance element are often used as noise countermeasures for a small electronic device.

[0003] The frequency band of noise that has been a problem in conventional electronic equipment is about several tens to several hundreds of MHz. On the other hand, the characteristics of the multilayer impedance element used for noise countermeasures are frequency characteristics having a peak of the impedance (resonance frequency) at a frequency of about 100 MHz or lower.

The impedance value of the used impedance element differs depending on the place in the electronic equipment used.
From 0 to a higher one, up to about 1000Ω is used.

[0005] In such a laminated impedance element, the conductor pattern in which the inner conductor is printed in a flat shape is wrapped around the magnetic layer in the thickness direction (lamination direction) to form a laminated coil. ing. In such a coil-shaped element having an internal conductor structure, its impedance is
Up to the resonance frequency (about 100 MHz), the following equation (1)
It is represented by

Z ² = X ² + R ² (1) X = 2π · f · L ′ (L ′ = Ae / 1 · N ² μ ₀ μ ′) R = 2π · f · L "(L" = Ae / l · N 2 μ 0 μ ") f: frequency, Ae / l: core constants, N: number of turns of the coil, mu _0: permeability of vacuum, μ'μ": used Relative permeability of magnetic material

Therefore, by adjusting the core constant determined by the size of the conductor coil, the number of turns of the coil, and the level of the magnetic permeability of the magnetic material to be used, it is possible to produce elements having various impedance values. .

In general, a thin-film impedance element uses a single-layer spiral pattern, and the obtained impedance is as low as several hundreds of ohms at 1 GHz. However, since the inductance value is low, a high resonance frequency of 1 GHz or more is obtained. Is obtained.

[0009]

In recent years, the signal frequency in electronic equipment has been significantly increased, and accordingly, it has become necessary to take measures against noise up to a higher frequency band.
Therefore, the frequency characteristic required for the impedance element serving as a noise countermeasure component, which has been conventionally up to about several hundred MHz, is required to maintain a high impedance up to the GHz band.

[0010] The current multilayer impedance element is:
An external electrode is formed in a lateral direction of the laminated coil with respect to a coil formed by laminating flat printed conductors in the thickness direction. Therefore, the stray capacitance between the external electrode and the internal conductor, particularly the coupling due to the stray capacitance at a portion close to the other external electrode in a half turn from one external electrode, greatly increases the resonance frequency of the impedance element. Affect.

That is, the resonance frequency of the impedance element is about several hundred MHz except when the inductance value is extremely small, and the impedance generally drops sharply at higher frequencies.

In the impedance element, several hundreds
Up to a resonance frequency of about MHz, the impedance represented by the above equation (1) is obtained. However, in the higher frequency band, as described above, the impedance of the coil component is high due to the coupling due to the stray capacitance parasitic on the conductor circuit, but the impedance of the stray capacitance component forming the circuit in parallel with the coil component is high. It drops sharply. Therefore, there is a problem that the impedance of the entire device becomes low.

In general, a thin-film impedance element uses a single spiral pattern, so that it is difficult to obtain a high inductance. Therefore, the resonance frequency expressed by the following (2) increases, but the impedance required for noise suppression cannot be obtained.

F ₀ = 1 / [2π · (L · C) ^1/2 ] (2)

On the other hand, as a conductor pattern having a small stray capacitance parasitic on a conductor circuit, there is a meander type or zigzag type pattern. In such a conductor pattern, since the stray capacitance is small, the resonance frequency is high, and the impedance does not decrease to the GHz band.

However, such a conductor pattern has a small inductance component (L ', L ") because the conductor is not in a coil shape.
There is a drawback that an impedance that contributes to noise suppression cannot be obtained.

As described above, the impedance elements include:
While high impedance characteristics are required from low frequency (several tens of MHz) to high frequency (GHz) required for noise countermeasures, a conventional multilayer impedance element has
The floating amount is large and high frequency impedance cannot be obtained.

In the conventional thin-film impedance element, low-frequency impedance cannot be obtained due to the shape of the conductor pattern.

Further, in a meander-type or zig-zag-type impedance element having a conductor pattern shape, there is a problem that although a stray capacitance is small, low-frequency impedance cannot be obtained.

Accordingly, an object of the present invention is to provide a thin-film impedance element capable of maintaining high impedance characteristics from a low frequency band of several tens of MHz to a high frequency band of several GHz.

[0021]

Accordingly, the present invention provides a zigzag structure or meander structure for the internal conductor, which is developed three-dimensionally, and has a special structure in which the current directions of adjacent conductors are the same. By devising and sharing the magnetic flux around the conductor, the impedance element can achieve high impedance.

That is, the present invention provides a thin-film impedance element comprising an insulating layer and an internal conductor formed by a thin-film forming method, and a pair of external electrodes connected to the internal conductor formed at both ends of the element. Is a thin-film electronic component in which a three-dimensionally expanded zigzag structure or meander structure is developed, and an internal conductor connected to one external electrode expands toward the other external electrode without returning.

Also, according to the present invention, the direction of the current of the internal conductor adjacent to the external electrode direction at both ends of the element is the same, except for the folded part of the internal conductor having the zigzag structure or meander structure. The thin-film electronic component according to the above-described electronic component, wherein a current direction of the internal conductor adjacent to the direction is a reverse direction.

[0024]

Embodiments of the present invention will be described below.

In the present invention, the inner conductor has a zigzag structure or meander structure which is developed three-dimensionally, and the inner conductor connected to one external electrode is developed without returning to the other external electrode. .

Except for the folded portion of the zigzag or meandering inner conductor, the direction of the current flowing through the inner conductor adjacent to the outer electrodes at both ends of the impedance element (in the horizontal direction) is the same, and By making the direction of the current flowing in the adjacent inner conductor reverse,
A thin-film impedance element exhibiting high impedance characteristics from low frequency (several tens of MHz) to high frequency (GHz) can be obtained.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a procedure for manufacturing a thin-film impedance element according to an embodiment of the present invention.

In FIG. 1, a glass substrate 1 [FIG.
(A)], a conductor (Cu) was formed in a pattern by a sputtering method, and a conductor 3 was made of copper (Cu) in a pattern including conductor extraction portions 2a and 2b [FIG. 1 (b)]. In addition, this time, a glass substrate was prepared as a substrate.
A u / polyimide composite substrate may be used.

The conductor 3 is formed thereon by a glass evaporation method.
The insulating layer 5 was formed in a pattern leaving the end 4 of FIG.
(C)].

Next, the inner conductor 6 was formed by the sputtering method (FIG. 1D), and the insulating layer 7 was formed by the glass evaporation method in the pattern of FIG. 1E.

Similarly, the sputtering method and the vapor deposition method shown in FIG.
(F), FIG. 1 (g), FIG. 1 (h), FIG. 1 (i), FIG.
(J) The conductor and the insulating layer of each pattern of FIG. 1 (k) were formed.

The conductor 3 was formed thereon with the final conductor pattern shown in FIG. 1 (l), and the entire conductor was formed into a single conductor circuit. Finally, glass was vapor-deposited on the whole to produce a thin-film impedance element.

FIG. 2 schematically shows a cross section, a current direction, and a magnetic flux flow of the manufactured impedance element.

Here, the conductor is formed by the sputtering method, but the same conductor can be formed by other conductor forming methods such as a vapor deposition method, a plating method, and a printing method. In addition, although the formation of the insulating layer is performed by a vapor deposition method, the same applies to other insulating layer forming methods such as a sputtering method and a printing method.

Also, except for the pattern including the first-layer conductor take-out portion and the final conductor in which the entire conductor is formed as a single conductor circuit, the conductor pattern has four rows and four layers.
Depending on the required impedance, impedance elements that extend to high frequencies can be obtained in any number of rows and layers as long as they are within the range of the length and thickness of the component.

Next, a comparative example of the above embodiment will be described with reference to FIG.

In FIG. 3, a 10-turn spiral conductor 9 having a conductor take-out portion 2 is formed on a glass substrate 1 by a sputtering method (FIG. 3A), and FIG. The insulating layer 15 having the pattern shown in FIG. Further, a conductor extraction portion 12 having a pattern shown in FIG. 3C was formed thereon by a sputtering method. Finally, glass was deposited on the entire surface to produce an impedance element.

Next, a conductive paste containing Ag as a main component was applied to the exposed portions of the impedance elements of the examples and the comparative examples, which were manufactured as described above.
Baking was performed at 00 ° C. to form external electrodes, thereby completing an impedance element.

FIG. 4 shows an external perspective view of the impedance element 10. The appearance after forming the external electrodes 8 is as follows.
The same applies to the examples and comparative examples.

The impedance characteristics of the thin-film impedance elements manufactured as described above were compared using a YHP impedance analyzer HP4291A.

FIG. 5 shows the frequency characteristics of the impedance of the impedance elements manufactured in the examples and comparative examples.

FIG. 5 shows that the impedance characteristic of the same change is shown in both the embodiment and the comparative example up to the frequency of 100 MHz. However, at a frequency of 1 GHz, the embodiment
High impedance of change equivalent to 00 MHz (10
00 Ω) or more, whereas the comparative example
It is greatly reduced to Ω or less.

According to this result, the structure of the internal conductor is a zigzag structure or a meander structure, which is developed three-dimensionally, and the current direction of adjacent conductors is the same, so that the magnetic flux around the conductors is shared. It has been clarified that an element exhibiting high impedance characteristics from a low frequency (several tens of MHz) to a high frequency (GHz) can be obtained.

In this embodiment, glass is used as the insulating layer. However, even if the insulating layer is formed of another insulating material, the same effect can be obtained as long as a thin film can be formed. Further, even if a soft magnetic thin film is formed inside the insulating layer to be insulated from the internal conductor, a component having a similar high impedance up to a high frequency can be obtained.

[0046]

As described above, according to the present invention,
The inner conductor has a zigzag structure or meander structure that is developed three-dimensionally, and the inner conductor connected to one of the external electrodes expands without returning to the other external electrode.
Furthermore, except for the folded portion of the zigzag or meandering inner conductor, the current directions of the inner conductors adjacent in the external electrode direction (horizontal direction) at both ends of the element are the same, and the currents of the inner conductors vertically adjacent to each other are the same. Are arranged in the opposite directions, so that a thin-film impedance element exhibiting high impedance characteristics from low frequency (several tens of MHz) to high frequency (GHz) can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a procedure for manufacturing a thin-film impedance element according to an embodiment of the present invention.

FIG. 2 is a diagram schematically showing a cross section, a current direction, and a magnetic flux flow of the thin film impedance element according to the embodiment of the present invention.

FIG. 3 is an explanatory view showing a procedure for manufacturing an impedance element of a comparative example to be compared with the product of the present invention.

FIG. 4 is an external perspective view of an impedance element.

FIG. 5 is a diagram illustrating frequency characteristics of impedance of impedance elements manufactured in Examples and Comparative Examples of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2, 2a, 2b, 12 Conductor taking-out part 3, 6, 9 (Inner) conductor 4 End 5, 7, 15 Insulating layer 8 External electrode 10 Impedance element

Claims (2)

[Claims] 1. A thin-film impedance element in which an insulating layer and an internal conductor are formed by a thin-film forming method, and a pair of external electrodes connected to the internal conductor are formed at both ends of the element. A thin-film electronic component having an expanded zigzag structure or meander structure, wherein an inner conductor connected to one external electrode expands toward the other external electrode without returning. 2. Except for a folded portion of the zigzag or meandering internal conductor, current directions of the internal conductors adjacent to the external electrodes at both ends of the element are the same direction and are adjacent in the vertical direction. 2. The thin-film electronic component according to claim 1, wherein the direction of the current flowing through the inner conductor is the opposite direction.