JPH05198440A - Coil for thin-film magnetic element and wire wound type thin film transformer - Google Patents

Abstract

PURPOSE:To improve the value of Q by providing the (n)-layered multiple structure of two or more layers for a coil, and decreasing the resistance to a large extent. CONSTITUTION:In a thin-film inductor having a mutilayer coil, which is formed by a film forming technology on an insulating substrate 2, a current flows in the sequence from a lower coil 12a to an upper coil 14a, from the upper coil 14a to a lower coil 13a and in the order of 13a 15a 12b 14b 13b 15 b 12c 14c 13c 15c a terminal. As a result, a magnetic core 8 is magnetized in the direction of an arrow 100. The respective coils are effectively operated as exciting conductors. When the double-layered multiple coil structure is provided, the width of the coil can be approximately doubled from the conventional coil as the same 6-turn coil. Thus, the resistance of the exciting conductor coil can be reduced to one half, and the thin-film magnetic element having the large Q value can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic element coil used in a thin film inductor, a transformer and the like, and a winding structure type thin film transformer.

[0002]

2. Description of the Related Art FIG. 5 is a perspective view of a conventional thin-film inductor shown in, for example, MAG90-125 of the Institute of Electrical Engineers of Japan Magnetics Research Group, and FIG. 6 is a side sectional view showing a section taken along the line AA 'in FIG. is there. In the figure, reference numeral 1 denotes a thin film inductor having a winding structure, which is formed on an insulating substrate 2. Excitation conductor coils are lower layer coils 4a to 4d and upper layer coils 5a to
5c, 6 is a joint between the lower layer coils 4a to 4d and the upper layer coils 5a to 5c, and 7a and 7b are terminals of the coil. Reference numeral 8 is a magnetic core made of a magnetic alloy thin film formed by a method such as sputtering. The lower layer coils 4a to 4d and the upper layer coils 5a to 5c have a structure in which they are wound around the magnetic core 8 via an insulating layer (not shown) such as a photoresist.

Next, the operation will be described. When a current I is made to flow from the terminals 7a to 7b in the direction of the arrow 9, the current flows from the lower coil 4a to the upper coil 5 as seen in the side cross section of FIG.
to a, and then to 4b, 5b, 4c, 5c, 4d. In the lower layer coils 4a to 4d, the current flows from the back side of the paper surface to the front side, and in the upper layer coils 5a to 5c, the current flows from the front side to the back side of the paper surface. Is excited in the direction. The exciting current I is an alternating current, and 1 operates as an inductor.

[0004]

The conventional thin film magnetic core inductor is constructed as described above, the thickness of the copper thin film of the exciting coil is as thin as 5 to 10 μm, the resistance R of the element is large, and the heat loss during operation is small. That is, there is a problem that the copper loss becomes large, and therefore the efficiency of the element, that is, the Q value is small.

The present invention has been made to solve the above problems, and an object thereof is to provide a coil for a thin film magnetic element having a small resistance and a large Q value and a winding structure type thin film transformer.

[0006]

In order to solve the above-mentioned problems, the present invention uses a coil having an n-layer multiple structure having two or more layers, so that the windings of the coils in each layer can be changed without changing the number of windings in the whole. The pitch can be reduced to about 1 / n, and the conductor width of the coil of each layer is about n times the coil width of the joint between the lower coil and the upper coil. Note that n is an integer satisfying n ≧ 2.

[0007]

The thin-film excitation conductor coil according to the present invention has an n-layer multi-layer structure, so that when the number of coil turns is the same, about n
The coil resistance R is reduced by a factor of 1, and as a result, the heat loss during operation is reduced and the Q value is improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view showing a winding structure type thin film inductor according to an embodiment of the present invention, and FIG. 2 is A- of FIG.
It is a side sectional view showing an A'section.

In FIG. 1, reference numeral 11 is a thin film inductor having a multi-structure coil formed on an insulating substrate 2 by a photoengraving technique and a film forming technique such as sputtering. 12
Is a lower first layer coil, 13 is a lower second layer coil, 1
4 is an upper layer first layer coil, 15 is an upper layer second layer coil,
Reference numeral 16 is a lower layer second layer coil 13 and an upper layer first layer coil 1
Reference numeral 17 denotes a joint portion between the lower layer first layer coil 12 and the upper layer second layer coil 15. Reference numerals 7a and 7b denote the terminals of the coil, and arrow 90 indicates the direction of the flow of the exciting current I.
Reference numeral 8 indicated by a broken line represents a thin film magnetic core.

1 and 2 show the case where the number of turns of the exciting conductor coil is 6 in order to simplify the description.
As shown in the side sectional view of FIG. 2, the current flowing from the terminal 7a to the terminal 7b in the direction of the arrow 90 is generated by the first layer coil 12 of the lower layer.
a to the first layer coil 14a of the upper layer, the first layer coil of the upper layer
From the layer coil 14a to the second layer coil 13a of the lower layer, 13a → 15a → 12b → 14b → 13b → 15b in that order.
The current flows in the order of → 12c → 14c → 13c → 15c → terminal 7b. As a result, in the lower layer coils 12a to 12c and 13a to 13c, the current flows from the front side to the back side of the paper, while in the upper layer coils 14a to 14c and 15a to 15c, the current flows from the rear side of the paper surface to the front side. As a result, the magnetic core (broken line) 8 is magnetized in the direction of arrow 100. Thus, it can be seen that each coil effectively operates as an exciting conductor. Further, regarding the width of the exciting conductor coil from the viewpoint of electric resistance, the coil width in the case of the conventional single winding is approximately the joint portion 16 of the lower layer coil and the upper layer coil,
Although it is the same as the width w of 17, it is understood that the width W of the coil can be approximately doubled with the conventional coil w with the same 6-turn coil by adopting the two-layer multiple coil structure.
As a result, the resistance of the exciting conductor coil can be halved, and a thin film magnetic element with a small loss and a large Q value can be obtained. Further, in the above embodiment, the case of the thin film inductor has been described, but the same effect can be obtained for the thin film transformer as shown in FIGS.

FIG. 3 is a perspective view of a thin film transformer showing another embodiment of the present invention, and FIG. 4 is a side sectional view showing a section AA 'in FIG. In FIG. 3, reference numeral 18 denotes a thin film transformer formed on the insulating substrate 2 by a photoengraving technique and a film-forming technique such as sputtering. For simplicity, the number of turns of the primary coil is 3 turns and the number of turns of the secondary coil is 4 turns. Show.
When a current flows from the terminal 21a to the terminal 21b in the direction indicated by an arrow 900, the primary coil starts from the terminal 21a, and the current starts from the lower layer second layer coil 13a to the upper layer first layer coil 14a.
To 14a → 13b → 14b → 13c → 14c
→ An exciting current flows to the terminal 21b. As a result, as shown in the side sectional view of FIG. 4, a current flows from the front side to the back side of the paper in the lower second layer coil 13 and from the back side to the front side of the first layer coil 14 in the upper layer, resulting in the magnetic core. (Dashed line) 8 is magnetized in the direction indicated by arrow 1000. This result 22a,
An induced electromotive voltage is induced in a secondary coil having 22b as a terminal to operate as a transformer. The secondary coil starts from the terminal 22a and proceeds from the lower layer first layer coil 12a to the upper layer second layer coil 15a in the order 15a → 12b → 15b → 1.
The coil is connected in the order of 2c → 15c → 12d → 15d and ends at the terminal 22b. At this time, as shown in FIG. 3, the joining portion 19 between the lower coil 13 and the upper coil 14 of the primary coil
By arranging the lower coil 12 of the next coil and the joint portion 20 of the upper coil 15 alternately, a transformer having a winding ratio of about 1: 1 can be obtained. By adopting the two-layer multiple coil structure, the width W of the coil can be almost doubled with respect to the width w of the joint portions 19 and 20 of the coil also in this case, and the same effect as that of the above-described one embodiment can be obtained. be able to.

The thin-film transformer has been described in the case where the turn ratio is about 1: 1. However, when a thin-film transformer having a turn ratio of 1: N (N is an integer) is obtained, the first thin film transformer in FIG. Joining portion 19 between the two-layer coil and the upper-layer first-layer coil
Is set to 1 and the number of joints 20 of the lower-layer first-layer coil and the upper-layer second-layer coil corresponding to the secondary coil is set to N, a thin film transformer with an arbitrary winding ratio can be easily formed. It can be obtained by adopting a two-layer multiple coil structure. In this case, the width W of the primary coil is equal to the coil joint 1
Since the width w of 9 can be made almost N times, there is an advantage that the resistance of the coil can be further reduced.

In the above embodiment, the case of the two-layer multiple coil structure has been described for the sake of simplicity. However, a three-layer multiple coil structure may be used, and n is an integer satisfying n ≧ 2. In this case, an n-layer multi-coil structure may be used. In this case, the coil width W of each layer can be about n times the width w of the joint between the upper-layer coil and the lower-layer coil. The resistance of the coil can be further reduced as compared with, and a magnetic element with less loss can be obtained.

[0014]

As described above, according to the present invention, in the thin film magnetic element having the winding structure, since the n-layer multiple winding structure is employed, the resistance R of the coil can be greatly reduced and the magnetic element having a large Q value. Can be obtained. Not only the thin-film inductor but also the thin-film transformer has the effect of being able to obtain a transformer having an arbitrary winding ratio with low resistance and low loss.

[Brief description of drawings]

FIG. 1 is a perspective view showing a thin film inductor according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing an AA ′ section of FIG.

FIG. 3 is a perspective view showing a thin film transformer according to another embodiment of the present invention.

4 is a side sectional view showing an AA ′ section in FIG.

FIG. 5 is a perspective view showing a conventional thin film inductor.

FIG. 6 is a side sectional view showing a section taken along the line AA ′ of FIG.

[Explanation of symbols]

2 ... Insulating substrate, 8 ... Magnetic core, 11 ... Thin film inductor, 12
... Lower layer first layer coil, 13 ... Lower layer second layer coil, 1
4 ... upper layer first layer coil, 15 ... upper layer second layer coil,
16 ... Joint between lower layer second layer coil and upper layer first layer coil, 17 ... Joint portion between lower layer first layer coil and upper layer second layer coil, 19 ... Lower layer coil and upper layer of primary coil Coil joint, 20 ... Joint between lower coil and upper coil of secondary coil.

Claims (3)

[Claims] 1. When n is an integer satisfying n ≧ 2,
A coil for a thin-film magnetic element, characterized in that an exciting conductor having a width of about n times a width of a joint portion between the lower-layer exciting conductor and the upper-layer exciting conductor is wound in n layers. 2. The joining portions of the exciting conductors are repeatedly arranged in units of n joining portions of the lower-layer first to n-th layer exciting conductors and the corresponding upper-layer exciting conductors. The coil for a thin film magnetic element according to claim 1. 3. The n is an integer satisfying n ≧ 2, and when N is an integer including 1, the joint between the lower layer exciting conductor and the upper layer exciting conductor of the primary coil and the lower layer exciting conductor of the secondary coil. A winding structure type thin film transformer having an n-layer multi-structure coil in which the above and an upper layer exciting conductor are repeatedly arranged at a ratio of 1: N.