JP4893367B2 - Thin film magnetic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin-film magnetic device capable of more efficiently improving a magnetic permeability in a high-frequency area. <P>SOLUTION: A strip-like area sandwiched by a plurality of slits 16 of a magnetic film 14 is configured so that magnetic segments 14De in a longitudinal direction of a widthwise direction (X-magnetic segment direction, magnetization easy axis Me direction) of the strip-like area are aligned along the longitudinal direction (Y-axis direction) of the strip-like area. With this configuration, in both cases where the magnetization easy axis Me and a coil 13 are substantially in parallel and orthogonal to each other, the magnetic permeability can be somewhat maintained in the high-frequency area. In this case, it is preferable to form the slits 16 in accordance with an area where the magnetization easy axis Me of the magnetic film 14 is substantially orthogonal to the coil 13, and to allow the slits 16 to extend in only the direction (magnetization hard axis Mh direction) orthogonal to the magnetization easy axis Me. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

The present invention relates to a thin film magnetic device having a thin film coil and the magnetic film.

  Conventionally, thin film magnetic devices such as thin film inductors and thin film transformers including thin film coils and magnetic films have been widely used as integrated passive components in the field of electronic equipment for various applications.

  FIG. 25 shows an example of a conventional thin film magnetic device (thin film inductor 101) configured by a rectangular spiral coil. FIG. 25 (A) shows a planar configuration, and FIG. 25 (B) shows FIG. Each cross-sectional structure of the III-III part shown to (A) is each represented. In this thin film inductor 101, a laminated film in which an insulating film 112, a rectangular spiral coil 113 having terminals 113T1 and 113T2, and a magnetic film 114 having an opening 115 at the center are laminated in this order on a substrate 111. It has a structure. In addition, when a predetermined magnetic field is applied to the magnetic film 114 in the X-axis direction at the time of film formation or the like, the magnetic field easy axis Me is formed in the magnetic field application direction (X-axis direction), but is orthogonal thereto. A magnetic field difficult axis Mh is formed in the direction (Y-axis direction), and exhibits uniaxial anisotropy.

  By the way, in recent years, in such a thin film magnetic device, a high frequency application in a GHz (gigahertz) band or the like is expected, and a magnetic film having good high frequency characteristics, specifically, a magnetic film exhibiting high permeability in a high frequency region. Is required.

  For example, in the conventional thin film magnetic device as shown in FIG. 25, since the thin film coil is a rectangular spiral coil, there are coil patterns extending in the X-axis direction and the Y-axis direction, respectively, and the easy magnetization axis Me. And those along the hard magnetization axis Mh are mixed. For this reason, the coil pattern (in the X-axis direction) in which the magnetization direction generated by the coil is orthogonal to the easy magnetization axis Me originally has a low permeability in the low frequency region, but maintains a certain degree of permeability up to the high frequency region. On the other hand, the coil pattern (in the Y-axis direction) whose magnetization direction is parallel to the easy magnetization axis Me has a high permeability in the low frequency region, but the permeability rapidly decreases in the high frequency region. Become. Therefore, the efficiency of using magnetic characteristics of the magnetic film is poor (about 50% in the case of a square spiral coil), and it is difficult to exhibit high magnetic permeability in a high frequency region.

  Therefore, for example, Patent Document 1 discloses that the easy magnetization axis directions of the magnetic films are different by using the shape magnetic anisotropy of the magnetic film in correspondence with the two-direction coil patterns formed by the rectangular spiral coil. The technique made to become is disclosed. Specifically, by forming a magnetic film separately in a magnetic field corresponding to the coil patterns in two directions, the coil patterns in both directions are perpendicular to the easy axis of magnetization, and the permeability in the high frequency region is improved. It is a thing.

  Further, for example, Patent Document 2 discloses a technique in which the easy axis of magnetization of a magnetic film is rotated by forming fine slits that circulate corresponding to the coil pattern of a rectangular spiral coil. Yes. Similarly to the above technique, the permeability in the high frequency region is improved by making the coil patterns in both directions orthogonal to the easy magnetization axis.

JP-A-8-172015 JP 2001-143929 A

  However, in the thin film magnetic devices disclosed in Patent Documents 1 and 2, the magnetic permeability in the high frequency region has not reached a practically sufficient level. Therefore, further improvement of the magnetic permeability in the high frequency region is desired.

  In particular, in the method of manufacturing a thin film magnetic device disclosed in Patent Document 1, it is necessary to separately form a magnetic film corresponding to a coil pattern in two directions, so that the conventional thin film magnetic device as shown in FIG. The manufacturing process is more complicated than that of the device, making it difficult to manufacture easily.

The present invention has been made in view of the above problems, purpose of that is to provide a thin film magnetic device capable of more effectively enhancing the permeability in the high frequency region.

The first thin-film magnetic device of the present invention, a thin film coil, this is laminated on the extending surface of the thin film coil, and a plurality of strip-shaped magnetic films which extend in one direction in the lamination plane, a plurality of these The band-shaped magnetic film is formed only in a region where the easy axis of magnetization of each band-shaped magnetic film and the thin film coil are orthogonal to each other with the direction perpendicular to the easy axis of magnetization as the longitudinal direction. The magnetic domain has a plurality of magnetic domains arranged along the direction, and the longitudinal direction of the magnetic domain coincides with the width direction of the belt-like magnetic film.

Second thin film magnetic device of the present invention includes a thin film coil, stacked on extending surface of the thin film coil, and a magnetic layer in which a plurality of slits extending in one direction are formed in the lamination plane, the plurality The slits of the magnetic film are formed only in the region where the easy axis of magnetization of the magnetic film and the thin film coil are orthogonal, with the direction perpendicular to the easy axis of magnetization as the longitudinal direction and sandwiched between the plurality of slits of the magnetic film A plurality of magnetic domains are arranged in the belt-like region along the longitudinal direction of the belt-like region, and the longitudinal direction of the magnetic domain coincides with the width direction of the belt-like region. The term “slit” means a strip-shaped or strip-shaped concave surface as well as a strip-shaped or strip-shaped opening.

In the thin film magnetic device of the present invention, a plurality of magnetic domains extend along the longitudinal direction of the strip-shaped magnetic film or the strip-shaped region, with the width direction of the strip-shaped region between the strip-shaped magnetic film or slit extending in one direction in the laminated plane as the longitudinal direction. Because they are lined up, the high frequency region regardless of the positional relationship between the easy magnetization axis of the belt-like magnetic film or magnetic film and the thin film coil, that is, both in the case where they are parallel to each other and perpendicular to each other A certain degree of permeability is maintained.
The band-like magnetic film or slit is formed only in a region where the axis of easy magnetization of the band-like magnetic film or magnetic film and the thin film coil are orthogonal to each other, with the direction orthogonal to the axis of easy magnetization as the longitudinal direction. This selectively increases the magnetic permeability at high frequencies in the region where the easy axis of magnetization and the thin film coil are orthogonal. Note that “orthogonally” includes not only a literally orthogonal aspect but also an approximately orthogonal aspect.

  In the thin film magnetic device of the present invention, the thin film coil includes a first coil pattern extending along the easy axis and a second coil pattern extending along a direction orthogonal to the easy axis. The band-like magnetic film or the slit can be formed along the second coil pattern.

  In the thin film magnetic device of the present invention, the width of the band-like magnetic film or band-like region is preferably 0.1 mm or more and 5 mm or less, more preferably 0.3 mm or more and 2 mm or less, and 0.3 mm or more and More preferably, it is 1 mm or less.

  In the thin film magnetic device of the present invention, the ratio of the length in the width direction of the magnetic domain to the length in the length direction of the magnetic domain is preferably 0.3 or less.

According to the thin film magnetic device of the present invention, a plurality of magnetic domains are arranged in the longitudinal direction of the strip-shaped magnetic film or the strip-shaped region while the longitudinal direction is the width direction of the strip-shaped magnetic film extending in one direction in the laminated surface or the strip-shaped region between the slits. Since the striped magnetic film or magnetic film easy magnetization axis and the thin film coil are parallel to each other or orthogonal to each other, a certain degree of permeability is maintained in the high frequency region. can do. Therefore, the magnetic permeability in the high frequency region can be improved more effectively.
In addition, the band-like magnetic film or slit is formed only in the region where the easy magnetization axis of the belt-like magnetic film or the magnetic film and the thin film coil are orthogonal to each other, and is extended in the direction perpendicular to the easy magnetization axis. It is possible to selectively increase the magnetic permeability at a high frequency in a region where the axis and the thin film coil are orthogonal to each other. Therefore, the magnetic permeability in the high frequency region can be further effectively improved.

  Hereinafter, the best mode for carrying out the present invention (hereinafter simply referred to as an embodiment) will be described in detail with reference to the drawings.

  1 and 2 show a configuration of a thin film inductor 1 as a thin film magnetic device according to an embodiment of the present invention. FIG. 1 shows an XY plane configuration, and FIG. 2 shows an II shown in FIG. It represents an XZ cross-sectional configuration along the line -II. The thin film inductor 1 has a laminated structure in which an insulating film 12, a thin film coil 13, and a magnetic film 14 are formed in this order on a substrate 11.

The substrate 11 is a rectangular substrate that supports the entire thin film inductor 1 and is made of, for example, glass, silicon (Si), aluminum oxide (Al ₂ O ₃ ; so-called alumina), ceramics, semiconductor, resin, or the like. . Note that the constituent material of the substrate 11 is not necessarily limited to the series of materials described above, and can be freely selected.

The insulating film 12 electrically insulates the coil 13 from the periphery and is made of, for example, an insulating material such as silicon oxide (SiO ₂ ).

  The coil 13 constitutes an inductor between one end (13T1) and the other end (13T2), and is made of a conductive material such as copper (Cu). The coil 13 has a rectangular spiral structure wound so that both the terminals 13T1 and 13T2 are led out to the outside in the XY plane, and the coil 13 extends along the X-axis direction. It has a pattern (first coil pattern) and a coil pattern (second coil pattern) extending along the Y-axis direction. In addition, the portion of the coil 13 that leads to the terminal 13T2 is arranged below the winding portion so that the portion that leads to the outside without contacting the winding portion that includes the portion that leads to the terminal 13T1 of the coil 13 is introduced. Has been. In FIG. 2, in order to simplify the illustration, the portion of the coil 13 that leads to the terminal 13T2 is not shown.

  The magnetic film 14 is for increasing the inductance of the thin film inductor 1 and has a rectangular opening 15 in the center. The magnetic film 14 has an easy magnetization axis Me in the X-axis direction and a hard magnetization axis Mh in the Y-axis direction, and exhibits uniaxial anisotropy. The magnetic film 14 is made of, for example, a magnetic material such as a cobalt (Co) alloy, an iron (Fe) alloy, or a nickel iron alloy (NiFe; so-called permalloy). Among these, as the cobalt-based alloy, for example, a cobalt zirconium tantalum (CoZrTa) based alloy or a cobalt zirconium niobium (CoZrNb) based alloy is preferable from the practical viewpoint of the thin film inductor 1. The shape of the opening 15 is not limited to a rectangular shape, and may be an arbitrary shape.

  In the magnetic film 14, the second coil pattern is formed in a region where the easy axis Me and the coil 14 are substantially orthogonal, that is, in a region corresponding to the second coil pattern extending in the Y-axis direction of the coil 14. A plurality of strip-shaped (strip-shaped) slits 16 extending in a direction substantially perpendicular to the easy magnetization axis Me, that is, in the Y-axis direction (hard magnetization axis Mh direction) are formed. From another point of view, the magnetic film 14 has four regions (four regions located above, below, left and right of the opening 15) obtained by dividing the extending region of the coil 13 along the winding direction. A plurality of slits 16 extending in one direction (Y-axis direction) are formed only in a pair of regions facing each other (here, two regions located on the left and right sides of the opening 15). The width of these slits 16 (slit width S) is about 5 μm to 20 μm, and the width of the magnetic film 14 between each slit 16 (pattern width L) is about 0.1 mm to 5 mm as will be described later. Here, each slit 16 penetrates the magnetic film 14, but is not limited to completely penetrate, and may be a strip-shaped (band-shaped) concave surface.

  Next, an example of a method for manufacturing the thin film inductor 1 will be described with reference to FIGS. 3 to 7 show an example of a method for manufacturing the thin-film inductor 1. FIGS. 3 and 5 show an XZ cross-sectional configuration, and FIGS. 4, 6 and 7 show an XY plane. Each configuration is shown.

  First, as shown in FIG. 3A, the insulating film 12 and the coil 13 are formed on the substrate 11 made of the above-described material. The insulating film 12 is formed by, for example, a sputtering method, and the coil 13 is formed by, for example, a plating method. Further, in order to embed the coil 13 in the insulating film 12 as shown in the figure, for example, the coil 13 is formed while the insulating film 12 is dividedly formed.

  Subsequently, as shown in FIG. 3B, the magnetic film 14 made of the above-described material is uniformly formed on the insulating film 12 and the coil 13. The magnetic film 14 is formed by, for example, a sputtering method.

Subsequently, as shown in FIG. 4, heat treatment is performed while applying a fixed magnetic field H <b> 1 within the laminated surface (XY plane) of the magnetic film 14. At this time, the application direction of the fixed magnetic field H1 is substantially parallel to one of the first and second coil patterns formed by the coil 13, that is, in this case, the X-axis direction or the Y-axis direction (the X-axis direction in FIG. 4). To become). The magnitude of the fixed magnetic field H1 is, for example, about 300 × 10 ³ / 4π [A / m] (= 300 Oe), the heat treatment temperature is, for example, about 330 ° C., and the heat treatment time is, for example, about 1 hour. Then, as shown in FIG. 5, the easy magnetization axis Me is generated along the application direction (X-axis direction) of the fixed magnetic field H1, and the hard magnetization axis Mh is generated along the direction (Y-axis direction) orthogonal to the application direction. The magnetic film 14 exhibits uniaxial anisotropy.

  Subsequently, as shown in FIG. 6A, a photoresist pattern 2 for forming the opening 15 and the slit 16 in the magnetic film 14 is formed by a photoresist method. The formation region of the photoresist pattern 2 corresponds to the formation region of the opening 15 and the slit 16, and as described above, the central portion of the magnetic film 14 is the formation region of the opening 15, and the easy magnetization axis Me. A region where the coil 14 and the coil 14 are substantially orthogonal, that is, a region corresponding to the second coil pattern extending in the Y-axis direction of the coil 14 is a formation region of the slit 16 and a direction substantially orthogonal to the easy magnetization axis Me, That is, a plurality of strip-shaped (strip-shaped) slits 16 are formed along the Y-axis direction (hard magnetization axis Mh direction).

  Subsequently, as shown in FIG. 6B, the magnetic film 14 is etched using a predetermined etching material to form the opening 15 and the slit 16.

  Finally, the thin film inductor 1 as shown in FIGS. 1 and 2 is manufactured by removing the photoresist pattern 2 using a predetermined resist removing material.

For example, as shown in FIG. 7, it is desirable to perform heat treatment while applying a rotating magnetic field H2 in the laminated surface (XY plane) of the magnetic film 14 thereafter. Since the stress on the magnetic film 14 is relaxed and the magnetic anisotropy is reduced, the permeability μh in the hard magnetization axis Mh direction can be further increased, and the inductance of the thin film inductor 1 can be further increased. is there. The magnitude of the rotating magnetic field H2 is, for example, about 300 × 10 ³ / 4π [A / m] (= 300 Oe), the rotational speed of the rotating magnetic field H2 is, for example, about 90 [rpm], and the heat treatment temperature is, for example, about 330 ° C. The heat treatment time is about 1 hour, for example.

  In the method of manufacturing the thin film inductor 1, the heat treatment is performed while applying the fixed magnetic field H1, and the slit 16 is formed after forming the easy magnetization axis Me and the hard magnetization axis Mh. After forming 16 (and opening 15), heat treatment may be performed while applying fixed magnetic field H1, as shown in FIG. 4, to form easy axis Me and hard axis Mh. Specifically, a slit 16 is formed in the laminated surface of the magnetic film 14 so as to be substantially parallel to a part of the coil 13, that is, one of the first and second coil patterns. Heat treatment is performed while applying a fixed magnetic field H1 in a direction perpendicular to the slit 16 in the (XY plane). Even when manufactured in this way, the thin film inductor 1 similar to the above case can be manufactured.

  Furthermore, in the manufacturing method of the thin film inductor 1 described above, after the magnetic film 14 is formed, heat treatment is performed while applying the fixed magnetic field H1, and the easy axis Me and the hard axis Mh are formed. The easy magnetization axis Me and the hard magnetization axis Mh may be formed by forming the magnetic film 14 while applying the fixed magnetic field H1 using the magnetron sputtering method. Even when manufactured in this way, the thin film inductor 1 similar to the above case can be manufactured.

  Next, the magnetic characteristics of the thin film inductor 1 formed in this way will be described in detail with reference to FIGS. 8 to 10 are examples of the frequency dependence of the magnetic permeability μ when the pattern width L is changed from 6 mm to 0.02 mm, and FIG. 11 is an example of the dependence of the magnetic permeability μ on the pattern width L. 12 shows an example of a magnetization curve (relation between applied magnetic field H and magnetization M), and FIG. 13 shows an example of a relationship between magnetic permeability μ and resonance frequency fr. 14 to 17 used magnetic colloids showing enlarged examples of the planar form of the magnetic film 14 when the pattern width L = 0.5 mm, 0.2 mm, 0.05 mm, and 0.02 mm, respectively. FIG. 18 schematically shows details of the magnetic domain structure shown in the micrograph, and FIG. 19 shows an example of the relationship between the 90 ° domain occupancy and the pattern width L described later. It represents. Note that the pattern width L = 6 mm in each figure corresponds to a conventional case in which the slit 16 is not formed, and is given as a comparative example.

The manufacturing conditions of the thin film inductor 1 in each example are as follows. First, the magnetic film 14 is formed using a DC magnetron sputtering method while applying a fixed magnetic field H1, and the target is CoZrTa. Further, when forming the slit 16, a positive resist for semiconductor is used to form the photoresist pattern 2, and an etching material (etchant) is iron chloride (FeCl ₃ ): H ₂ O: hydrogen fluoride (HF). ) = 1: 2: 0.2, and acetone is used as a resist remover. Further, an impedance analyzer is used for evaluating the manufactured thin film inductor 1, and a ferrite yoke method is used as a measuring method.

First, according to the frequency dependence of the magnetic permeability μ shown in FIGS. 8 to 10, the magnetic permeability μh in the direction perpendicular to the application direction of the fixed magnetic field H <b> 1 (direction of hard magnetization Mh) is the pattern width L = 6 mm˜0. On the other hand, the permeability μe in the horizontal direction (direction of easy magnetization Me) of the application direction of the fixed magnetic field H1 hardly changes to 1 mm, and the slit 16 having L = 6 mm is formed as the value of the pattern width L decreases. From the comparative example, the slit 16 is formed and the pattern width L becomes narrower), so that the magnetic permeability μe is lowered and a certain value is maintained up to the high frequency region (approximately when L = 0.2 mm). 10 ⁷ Hz = about 10 MHz), and it can be seen that the resonance frequency fr also increases.

  The relationship between the magnetic permeability μ and the pattern width L is summarized as shown in Table 1 below. FIGS. 11A and 11B are graphs based on the values shown in Table 1. FIG. 11A shows the case where the frequency is f = 1 kHz. 11 (B) represents the case where the frequency is f = 1 MHz.

  According to Table 1 and FIGS. 11A and 11B, first, the permeability μh in the vertical direction hardly changes regardless of the pattern width L even when the frequencies are f = 1 kHz and 1 MHz. I understand. Further, in the case where the frequency f = 1 kHz in the relatively low frequency region (FIG. 11A), the horizontal magnetic permeability μe monotonously decreases as the value of the pattern width L decreases, whereas in the high frequency region, In the case of the frequency f = 1 MHz (FIG. 11B), it increases once as the value of the pattern width L becomes smaller compared to the comparative example (L = 6 mm), and has a peak value near L = 0.5 mm. I understand that Therefore, in order to increase the magnetic permeability μ in such a high frequency region, the slit 16 is formed, and as can be seen from FIG. 11B, the pattern width L between the plurality of slits is 0.1 mm or more and 0. It is desirable that it is about 5 mm or less. Further, in order to further increase the magnetic permeability μ, the pattern width L is more preferably 0.3 mm or more and 2 mm or less, and further preferably 0.3 mm or more and 1 mm or less.

  Here, with reference to FIGS. 12A and 12B, the following is considered when the relationship between the formation of the slit 16 and the increase in the magnetic permeability μ in the high frequency region is considered. 12A shows the magnetization curve in the comparative example (L = 6 mm) in which the slit 16 is not formed, and FIG. 12B shows the magnetization in the case where the slit 16 is formed (L = 0.5 mm). Each curve is represented.

  First, it is known that the following equations (1) and (2) are established between the anisotropic magnetic field Hk and the magnetic permeability μ or the resonance frequency fr in the hard magnetization axis Mh direction of the magnetic film. However, these equations (1) and (2) are considered to hold in the same manner in the direction of the easy axis Me. In the equation, Bs represents a saturation magnetic flux, Ms represents a saturation magnetization, μ0 represents a magnetic permeability in vacuum, and γ represents a magnetorotation ratio.

  When focusing on the easy magnetization axis Me direction, the magnetization curve shown in FIG. 12B has an inclination compared to the magnetization curve of the comparative example shown in FIG. 12A due to the influence of the demagnetizing field Hd. The value of the anisotropic magnetic field Hk increases (Hk increases to (Hk + Hd)). Therefore, it can be seen from the equations (1) and (2) that the value of the magnetic permeability μ decreases, but the resonance frequency fr increases, so that the magnetic permeability μ can maintain a certain value up to the high frequency region. . In this way, the value of the anisotropic magnetic field Hk increases due to the influence of the demagnetizing field Hd, so that the horizontal magnetic permeability μe in the high frequency region increases and the magnetic permeability μ increases as a whole.

  Table 2 summarizes the relationship between the resonance frequency fr and the horizontal magnetic permeability μe when the pattern width L is changed from 6 mm to 0.02 mm. FIG. 13 is a graph based on the values shown in Table 2.

  Also from Table 2 and FIG. 13, as the slit 16 is formed and the value of the pattern width L becomes smaller, the value of the horizontal magnetic permeability μe itself decreases, but the resonance frequency fr increases. I understand.

  Next, according to the micrographs of the magnetic film 14 shown in FIGS. 14 to 17, a plurality of magnetic domains magnetized in the width direction (X-axis direction) of each slit 16 are formed in the slit 16 of the magnetic film 14. It turns out that it is located in a line along the longitudinal direction (Y magnetic domain direction) of the sandwiched band-like region. Further, even if the pattern width L is narrowed from FIG. 14 to FIG. 17, the lateral domain, that is, the magnetic domain structure in the width direction (X-axis direction) of the band-shaped region remains laterally long, and 90 ° of the easy axis Me It can be seen that a phenomenon such as rotation does not occur. However, as the pattern width L becomes narrower, the aspect ratio of the magnetic domain (ratio of the length in the minor axis direction to the length in the major axis direction of the magnetic domain) changes and gradually changes toward the square (the aspect ratio increases). ) The aspect ratio of each magnetic domain is desirably 0.3 or less because of the relationship with the 90 ° domain occupancy described below. This is because the magnetic permeability μ can be maintained to a higher frequency side due to the influence of the demagnetizing field Hd as described above.

  Furthermore, the spike structure as indicated by reference signs P1 and P2 in FIG. 14 (L = 0.5 mm) disappears and changes in FIGS. 15 to 17 (L = 0.2, 0.05, 0.02 mm). Are formed such that triangular domains (90 ° domains) having the longitudinal direction (Y-axis direction) of the slits 16 as indicated by reference numerals P3 to P5 extend along the longitudinal direction. It can be seen that they are located at both ends of the magnetic domain having the magnetization direction (X-axis direction).

  FIG. 18 schematically shows these magnetic domain structures and corresponds to the magnetic film 14 having a pattern width L existing between the slits 16. Here, as described above, a plurality of magnetic domains 14D are formed and extend along the longitudinal direction (Y-axis direction, hard magnetization axis Mh direction). Each of the magnetic domains 14D includes a pair of magnetic domains 14De whose magnetization direction is the above-described width direction (X magnetic domain direction, easy magnetization axis Me direction), and a pair of magnetic domains 14De whose longitudinal direction is the magnetization direction and positioned at both ends of the magnetic domain 14De. It is composed of a magnetic domain (90 ° domain) 14Dh. In addition, the magnetization directions by the magnetic domains 14De and 14Dh constitute a closed loop, and the adjacent magnetic domains 14D are opposite to each other in the closed loop direction.

  Further, according to the relationship between the pattern width L shown in FIG. 19 and the 90 ° domain occupancy in the magnetic domain 14, the 90 ° domain occupancy is almost 0% when the pattern width L is 0.5 mm or more. Although it hardly exists in the magnetic domain 14, when the pattern width L is less than 0.5 mm, it can be seen that the 90 ° domain occupancy increases monotonously. Further, as shown in FIG. 11B, the permeability μe in the horizontal direction (easy magnetization axis Me direction) has a peak value near the pattern width L = 0.5 mm. It can also be seen that the horizontal permeability μe, which tends to increase as the pattern width L illusions, tends to decrease as the pattern width L increases. Therefore, from these results, in order to more effectively improve the magnetic permeability μ in the high frequency region, it is desirable that the 90 ° domain occupancy is 12% or less.

  As described above, in the present embodiment, in the band-shaped region sandwiched between the plurality of slits 16 in the magnetic film 14, the width direction (X magnetic domain direction, easy axis Me direction) of the band-shaped region is defined as the longitudinal direction. Since the magnetic domains 14De to be aligned are arranged along the longitudinal direction (Y-axis direction) of the belt-like region, the magnetization easy axis Me and the coil 13 are substantially parallel to each other and substantially orthogonal to each other. In any case, a certain degree of magnetic permeability can be maintained in the high frequency region. Therefore, the magnetic permeability in the high frequency region can be improved more effectively.

  In particular, in the present embodiment, the slit 16 is formed corresponding to only the region where the easy axis Me of the magnetic film 14 and the coil 13 are substantially orthogonal to each other, and the direction in which the slit 16 is orthogonal to the easy axis Me (magnetization). Since it is made to extend in the direction of the difficult axis Mh), the magnetic permeability at high frequency in a region where the easy magnetization axis Me and the coil 13 are substantially orthogonal (region corresponding to the second coil pattern in which the slit 16 extends). Can be selectively increased. Therefore, a certain degree of magnetic permeability can be maintained in the high frequency region not only in the region where the easy axis Me and the coil 13 are substantially parallel (region corresponding to the first coil pattern) but also in the region substantially orthogonal to each other. It becomes possible to further effectively improve the magnetic permeability in the high frequency region.

  Further, since the band-shaped region is formed so as to overlap the second coil pattern of the coil 13, the distance between the magnetic film 14 and the second coil pattern in the band-shaped region can be shortened, and the magnetic permeability can be further improved. It becomes possible.

  Further, in the belt-like region, the magnetic domains 14Dh (90 ° domain) are arranged along the longitudinal direction (Y-axis direction) of the belt-like region while being arranged opposite to both ends in the width direction (X-axis direction) of the belt-like region. Therefore, it is possible to effectively promote the increase in the resonance frequency fr caused by the demagnetizing field Hd in the magnetic domain 14De sandwiched between the pair of magnetic domains 14Dh. Therefore, the magnetic permeability in the high frequency region can be further effectively improved.

  Furthermore, according to the manufacturing method of the thin film inductor 1 as the thin film magnetic device of the present embodiment, the manufacturing process is not particularly complicated. Therefore, a thin film magnetic device exhibiting high permeability in the high frequency region as described above is provided. It can be easily obtained.

  In the present embodiment, the case where the slit 16 is formed corresponding to only the region where the easy axis Me and the coil 13 are substantially orthogonal to each other has been described. However, in addition to this, other regions such as FIG. As in the thin film inductor 1A shown in FIG. 1, the slits 16 may be formed on a diagonal line from the opening 15 on the magnetic film 14A. That is, a plurality of strip-like magnetic films 14A may be formed along one direction (in this case, the easy axis Me direction and the X axis direction) in the laminated surface. Even when configured in this manner, the same effects as in the present embodiment can be obtained.

  While the present invention has been described with reference to the embodiment, the present invention is not limited to this embodiment, and various modifications can be made.

  For example, in the above-described embodiment, the slit 16 is formed corresponding to only a region where the easy axis Me and the coil 13 are substantially orthogonal to each other, but in addition to this, other regions, for example, the thin film shown in FIG. Like the inductor 1A, the slit 16 may be formed on a diagonal line from the opening 15 on the magnetic film 14A.

  Moreover, although the said embodiment demonstrated the case where the coil 13 was comprised from the rectangular spiral coil which has the 1st and 2nd coil pattern substantially orthogonal to each other, the shape of the coil 13 which is a thin film coil is This is not a limitation. For example, like the thin film inductors 1C to 1E shown in FIGS. 21A to 21C, the magnetic films 14C to 14E are circular (may be elliptical), and for example, the coil 13 is also a circular spiral. It may be the case. In this case, the slit 16 may be formed along a direction (hard magnetization axis Mh direction) orthogonal to the easy magnetization axis Me regardless of the shape of the coil 13. Further, for example, as in the thin film inductor 1F shown in FIG. 22, the coil 13 may be a rectangular spiral coil instead of a square shape.

  Further, the coil may be a meander coil 13G having a rectangular shape, for example, like a thin film inductor 1G shown in FIG. 23, and the coil may be a solenoid coil 13H, for example, like the thin film inductor 1H shown in FIG. There may be.

  In the above embodiment, the thin film inductor has been described as an example of the thin film magnetic device, but the present invention can also be applied to a thin film transformer or the like. That is, as long as the magnetic film described in the above embodiment and a predetermined electrode are provided, the present invention is not limited to a thin film inductor, and can be widely applied as a thin film magnetic device.

  Further, the material, film formation method, and film formation conditions of each layer described in the above embodiment are not limited, and other materials and thicknesses may be used, and other film formation methods and film formation conditions may be used. Good.

It is a top view showing the plane composition of the thin film magnetic device concerning one embodiment of the present invention. It is sectional drawing showing the cross-sectional structure of the thin film magnetic device along the II-II line | wire shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the thin film magnetic device shown in FIG. It is a top view for demonstrating the manufacturing method of the thin film magnetic device following FIG. It is a top view for demonstrating the manufacturing method of the thin film magnetic device following FIG. It is sectional drawing for demonstrating the manufacturing method of the thin film magnetic device following FIG. It is a top view for demonstrating the manufacturing method of the thin film magnetic device following FIG. It is a characteristic view showing an example of the frequency dependence of the magnetic permeability in the thin film magnetic device shown in FIG. It is a characteristic view showing an example of the frequency dependence of the magnetic permeability in the thin film magnetic device shown in FIG. It is a characteristic view showing an example of the frequency dependence of the magnetic permeability in the thin film magnetic device shown in FIG. It is a characteristic view showing an example of the pattern width dependence of the magnetic permeability in the thin film magnetic device shown in FIG. It is a characteristic view showing an example of the magnetization curve in the thin film magnetic device shown in FIG. 1 with the thing of a comparative example. It is a characteristic view showing an example of the relationship between the magnetic permeability and resonance frequency in the thin film magnetic device shown in FIG. It is a microscope picture which expands and shows an example of the plane form of the magnetic film shown in FIG. It is a microscope picture which expands and shows an example of the plane form of the magnetic film shown in FIG. It is a microscope picture which expands and shows an example of the plane form of the magnetic film shown in FIG. It is a microscope picture which expands and shows an example of the plane form of the magnetic film shown in FIG. It is a schematic diagram for demonstrating the detail of the magnetic domain structure shown in FIGS. It is a characteristic view showing an example of the relationship between the occupation rate of a 90 degree domain and pattern width in the thin film magnetic device shown in FIG. It is a top view showing the plane composition of the thin film magnetic device concerning the modification of the present invention. It is a top view showing the plane composition of the thin film magnetic device concerning the modification of the present invention. It is a top view showing the plane composition of the thin film magnetic device concerning the modification of the present invention. It is a top view showing the plane composition of the thin film magnetic device concerning the modification of the present invention. It is a top view showing the plane composition of the thin film magnetic device concerning the modification of the present invention. It is the top view and sectional drawing showing the structure of the conventional thin film magnetic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1A, 1C-1H ... Thin film inductor, 11 ... Board | substrate, 12 ... Insulating film, 13, 13F-13H ... Coil, 13T1, 13T2 ... Terminal, 14, 14A, 14C-14H ... Magnetic film, 14D, 14Dh ... Magnetic domain , 14Dh: Magnetic domain (90 ° domain), 15: Opening, 16, 17: Slit, 2: Photoresist pattern, Me: Easy magnetization axis, Mh: Hard magnetization axis, L: Pattern width, S: Slit width, H1 ... Fixed magnetic field, H2 ... rotating magnetic field, m ... magnetization direction.

Claims (7)

A thin film coil;
A plurality of strip-like magnetic films laminated on the extending surface of the thin film coil and extending in one direction in the laminated surface;
The plurality of strip-like magnetic films are formed only in a region where the magnetization easy axis of each strip-like magnetic film and the thin-film coil are perpendicular to each other, with the direction perpendicular to the easy magnetization axis as a longitudinal direction,
The band-shaped magnetic film has a plurality of magnetic domains arranged along the longitudinal direction of the band-shaped magnetic film,
A thin film magnetic device, wherein a longitudinal direction of the magnetic domain coincides with a width direction of the belt-like magnetic film. A thin film coil;
A magnetic film laminated on the extending surface of the thin film coil, and formed with a plurality of slits extending in one direction in the laminated surface;
The plurality of slits are formed only in a region where the easy axis of magnetization of the magnetic film and the thin film coil are orthogonal, with the direction orthogonal to the easy axis as the longitudinal direction,
A plurality of magnetic domains are arranged along the longitudinal direction of the band-shaped region in the band-shaped region sandwiched between the plurality of slits of the magnetic film,
A thin film magnetic device, wherein a longitudinal direction of the magnetic domain coincides with a width direction of the band-like region. The thin film coil is
A first coil pattern extending along the easy axis;
A second coil pattern extending along a direction orthogonal to the easy axis of magnetization,
The thin-film magnetic device according to claim 1 , wherein the strip-shaped magnetic film or the slit is formed along the second coil pattern. The strip magnetic film or the width of the strip-like regions, the thin-film magnetic device according to any one of claims 1 to 3, characterized in that at 0.1mm or more and 5mm or less. The thin film magnetic device according to claim 4 , wherein a width of the band-shaped magnetic film or the band-shaped region is 0.3 mm or more and 2 mm or less. The thin film magnetic device according to claim 5 , wherein a width of the band-shaped magnetic film or the band-shaped region is 0.3 mm or more and 1 mm or less. Longitudinal ratio of the length in the width direction of the magnetic domain to the length of the magnetic domains, the thin-film magnetic device according to any one of claims 1 to 6, characterized in that less than 0.3 .

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