JP2003257739A - High-frequency device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-frequency device, such as the high-frequency inductor, high-frequency transformer, transmission-line device, etc., usable in such a high-frequency band (GHz band) that has been considered to be difficult to be used for the device. <P>SOLUTION: When a microstrip line type transmission line, etc., is constituted by using a laminated film of a ferromagnetic metallic film and an antiferromagnetic thin oxide film, action of the antiferromagnetic thin oxide film as dielectrics can be utilized. At the same time, ferromagnetic resonance frequency of the ferromagnetic metallic film can be raised to a significantly high frequency by inducing large one-directional magnetic anisotropy through ferromagnetic/antiferromagnetic exchange bonding, and an extremely effective means for widening the band of the transmission line can be obtained. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency inductor and a high frequency transformer used for information communication equipment, various transmission lines and devices using the transmission lines, and a thin film magnetic head for high frequency magnetic recording. .

[0002]

2. Description of the Related Art At present, in a personal computer, the processing speed is dramatically improved together with the increase in the clock frequency of the CPU chip. Now, a CPU chip having a clock frequency exceeding 1 GHz is being developed. On the other hand, mobile phones, PHS, PDA, Bl
The wireless information communication system using the microwave band, as represented by Bluetooth, wireless LAN, ITS equipment, etc., is becoming more important as an important infrastructure supporting an advanced information society. Common to many of these information and communication devices is that
The signal frequency may reach several 100 MHz to nearly 10 GHz, and there is a possibility that the frequency will be further increased in the future.

Many passive components such as inductors, capacitors and resistors are used in the high frequency circuits of these wireless information communication systems. FIG. 36 shows a configuration example of the MMIC module of the RF amplifier for PHS,
In addition to the FET input / output matching circuit, inductors and capacitors are often used in the FET bias circuit.
FIG. 37 is a chip photograph of the RF module shown in FIG. As is clear from the figure, the occupied area of the air-core spiral inductor occupies the entire chip, which is a major factor inhibiting the reduction of the chip size.

Recently, as an inductor for a MMIC high frequency circuit of a mobile communication terminal such as a mobile phone or PHS, an attempt has been made to reduce the size of the inductor by adding a magnetic material to the conventional air-core spiral inductor to reduce the cost. It has become popular (for example, Masahiro Yamaguchi, Kenichi Arai; Journal of Japan Society for Applied Magnetics, Vol. 25, No. 2, 59, 2001). Figure 3
Reference numeral 8 shows an example of an RF magnetic thin film inductor, which has a structure in which the upper and lower sides of the spiral coil 174 are sandwiched by magnetic films via an insulating film. In this case, the upper and lower thin film magnetic cores 1
71 and 176 are formed by finely processing a ZrNb amorphous alloy magnetic film into a microwire array to improve the magnetic characteristics at high frequencies. Generally, the limit frequency of a ferromagnetic material is determined by various magnetic resonance phenomena. For example, the ferromagnetic resonance frequency f _r when by applying a high frequency magnetic field to the magnetization hard axis of the magnetic film having a uniaxial magnetic anisotropy utilizing magnetization rotation mode is given by equation (1).

[0005]

[Equation 1] Here, γ is a gyro magnetic constant, Ms is a saturation magnetization, and Hk is an anisotropic magnetic field.

The limit frequency of a ferromagnetic material is determined by f _r ,
To increase this frequency, a magnetic material with large Ms and Hk must be used. A magnetic film microwire array 17 used in the magnetic thin film inductor shown in FIG.
7, the magnetization in the wire is oriented in the wire longitudinal direction due to the demagnetizing effect. The effective anisotropic magnetic field at this time is (2)
It is expressed as

[0007]

[Equation 2] Here, N _d is a demagnetizing factor in the width direction of the microwire. In this case, the effective anisotropy field is increased by the demagnetizing field effects, the ferromagnetic resonance frequency f _r, as shown in equation (3) is shifted to the high frequency side.

[0008]

[Equation 3] Due to the micro-patterning of the CoZrNb magnetic film, the critical frequency of the magnetic film is increased from about 1 GHz to 2 GHz or higher, and a magnetic thin film inductor using this is
At a frequency of 2 GHz, the inductance is increased by + 19% and the Q value is increased by + 23% with respect to the air-core spiral inductor, clearly showing the performance improvement by adding the magnetic material.

The magnetic susceptibility χ in the direction of the hard axis of a magnetic substance having uniaxial magnetic anisotropy is given by the equation (4) and is inversely proportional to the effective anisotropic magnetic field. A method of increasing the limit frequency of the magnetic film inevitably reduces the magnetic susceptibility.

[Equation 4]

Therefore, in order to increase the critical frequency of the magnetic film while maintaining a high magnetic susceptibility χ, a magnetic material having a large saturation magnetization Ms is essential. In general, it is not easy to produce a magnetic material that has both a high Ms and a large Hk, and even among many magnetic thin film materials developed to date, there are few actual examples of materials having a limit frequency exceeding 5 GHz. It's a reality. Although high-frequency inductors and high-frequency transformers for the microwave band are strongly demanded as high-frequency circuit elements, the limit frequency of magnetic thin film materials is only a few GHz, and there are great expectations for the realization of ultra-high frequency magnetic thin film materials. There is.

On the other hand, in microwave circuits of several GHz to several tens GHz, transmission line devices using a dielectric are often used for impedance converters, balancers, high frequency filters and the like. Since each of these lines functions as an LC composite circuit by itself, there is an advantage that the number of parts can be significantly reduced as compared with a case where an inductor and a capacitor are combined. 39 and 40 show schematic configurations of typical microstrip lines and coplanar lines. FIG. 41 shows a circuit configuration example of a 50 GHz band low noise amplifier. As the circuit configuration example shows, a quarter-wavelength coplanar line is often used for an input / output matching circuit of a FET, a bias circuit, and the like.

FIG. 42 is an equivalent circuit when the transmission line is represented by a distributed constant circuit. When the line loss is small, the ratio of the line wavelength λg to the electromagnetic field wavelength λ in the free space (λg / λ) can be approximated by the equation (5).

[Equation 5]

Here, μo is the magnetic permeability in vacuum, and εo is the dielectric constant in vacuum. L o and C o are the inductance and capacitance per unit length of the line in FIG. For example, if the permeability of the dielectric is μ and the permittivity is ε, then L o and C o in the microstrip line using this are
It is expressed as in equation (6).

[Equation 6]

After all, λg / λ becomes simple as shown in the equation (7).

[Equation 7] Here, μs and εs are the relative permeability and relative permittivity of the dielectric material.

At present, transmission line devices that are actually put into practical use in the microwave band often use a nonmagnetic low dielectric constant dielectric material such as alumina or polyimide, and the relative magnetic permeability μs is substantially 1. Therefore, the line wavelength in this case is 1 / (εs) ^1/2 times the free space wavelength. Since transmission line devices are one of the wave devices that use standing waves, the shorter the wavelength of the line, the more compact the device can be.However, transmission line devices using polyimide or alumina have the effect of shortening the wavelength. Since these are not large, their use is limited to frequencies above the microwave band. For example, the wavelength of alumina having a relative permittivity of about 9 is about 1/3 of the free space, and that of polyimide having a relative permittivity of about 4 is only about 1/2 of the free space. If these are used in the quasi-microwave band of several 100 MHz to several GHz, the line wavelength becomes long, and the application to actual circuits is greatly limited.

Recently, a magnetic / dielectric hybrid transmission line device having a remarkably large wavelength shortening effect has been proposed for the purpose of application to various information communication devices utilizing the quasi-microwave band of several 100 MHz to several GHz, and it is very large. Expectations are high (for example, Toshiro Sato, Shinji Ikeda, Kiyoto Yamazawa; Journal of Applied Magnetics, Vol. 22, No. 3, 133, 199).
8). According to the experimental results of the laminated type microstrip line using the CoZrNb amorphous alloy magnetic thin film and the polyimide film, it is only necessary to insert one layer of the CoZrNb film having the thickness of 1 μm into the polyimide having the thickness of 2 μm. It is shown that the line wavelength is shortened (Yasuyuki Maruyama, Shinji Ikeda, Toshiro Sato, Kiyoto Yamazawa; The Institute of Electrical Engineers of Japan, Magnetics Research Group, MAG-01-121, 2001). For a free space wavelength of 600 mm at a frequency of 500 MHz,
The wavelength of the polyimide line is about 300 mm, and the wavelength of the CoZrNb / polyimide hybrid line is about 37.5 mm. The 1/4 wavelength line can be applied to an impedance converter, a resonator, a filter, etc. by itself, and CoZrNb /
By using the polyimide hybrid line, a quarter wavelength line device can be constructed with a short line length of about 9.4 mm. As described above, the magnetic / dielectric hybrid transmission line has a greater wavelength shortening effect than a line composed of a dielectric alone, and is small in transmission even at frequencies below the quasi-microwave band, where there are almost no conventional applications. The possibility of realizing a track device was opened up.

However, the Co used here
Since the limit frequency (ferromagnetic resonance frequency) of the ZrNb magnetic film is about 900 MHz, the same wavelength shortening effect cannot be used in the GHz band. Therefore, similarly to the above-described high frequency inductor and high frequency transformer, the problem of the limiting frequency of the magnetic substance is serious in the magnetic substance / dielectric hybrid line, and there are great expectations for the realization of an ultra-high frequency magnetic thin film material.

In the hard disk drive, which is an information recording device, high-speed writing / reading is required for high-speed data transfer with a personal computer or the like, and at present, the recording frequency has reached several hundreds MHz, which is about to come. 1G
It is expected to exceed Hz. FIG. 43 shows an example of the structure of a recording / reproducing integrated thin film magnetic head. The recording density of the hard disk drive was dramatically improved by reducing the recording bit size by increasing the coercive force of the magnetic recording medium and by reading with high sensitivity by the spin valve head 194. However, for magnetic recording on a high coercive force magnetic recording medium, a magnetic material for a recording head having high saturation magnetization is required, and in addition, for high frequency recording, high frequency magnetic characteristics corresponding thereto are required. In the thin film magnetic head for magnetic recording, there is a demand for realization of a magnetic thin film material having a high critical frequency and a high saturation magnetization, which are similar to the problems of the high frequency device described above.

On the other hand, recently, an interesting research result has been reported which provides a clue for an ultra-high frequency magnetic thin film material. Jung et al. Of the University of Alabama, US
An FeTaN / IrMn exchange-coupling laminated film was prepared and its properties were reported (HS Jung, WD Doyle; The 8th.
MMM-Intermag Conference in San Antonio, USA, ES-0
5, Jan. 2001). Backing the soft magnetic layer to the base of the recording medium,
In the perpendicular magnetic recording method for writing with a single pole head,
It has been pointed out that the instability of the magnetic domain that induces the domain wall motion of the soft magnetic underlayer is a significant factor of medium noise, and in order to satisfy both the medium noise reduction and high frequency recording, the soft magnetic underlayer has a magnetic domain. Strong pinning and fast magnetization reversal are required. As a soft magnetic underlayer, Jung et al. Developed an exchange-coupling laminated film in which a FeTaN ferromagnetic metal film having a high saturation magnetization and an IrMn antiferromagnetic metal film are alternately laminated. The ferromagnetic metal / antiferromagnetic exchange coupling imposes a strong exchange coupling bias magnetic field on the ferromagnetic layer, which causes the magnetic domains to be strongly pinned.

FIG. 44 shows an example of the magnetization curve of the FeTaN / IrMn exchange-coupling laminated film. The magnetization curve observed in the easy axis direction (domain wall motion mode) is laterally shifted due to the exchange-coupling bias, and the external magnetic field is generated. The magnetization at zero is almost equal to the saturation magnetization Ms, and it can be seen that the magnetic domains are strongly pinned. The magnetization curve (magnetization rotation mode) observed in the hard axis direction has a small hysteresis, and the apparent effective anisotropic magnetic field Hk (eff.) Is about 120 Oe and Fe.
The TaN film is enhanced by about 8 times as much as Hk in the case of using it alone. The FeTaN film has a high saturation magnetization Ms of more than 1.8 T, and coupled with the large effective anisotropy Hk (eff.) Enhanced by exchange coupling with the IrMn film, the ferromagnetic resonance frequency fr of the magnetization rotation is 4. It reaches 2 GHz. Figure 45
Shows the frequency characteristic of the complex magnetic permeability of the [FeTaN (20 nm) / IrMn (10 nm)] exchange-coupling laminated film.
No sign of resonance appears even at the frequency of GHz.

A laminated film in which a ferromagnetic layer having a high saturation magnetization and an antiferromagnetic layer are alternately laminated is extremely easy to obtain both a high saturation magnetization and a large anisotropy magnetic field, and will be used for super high frequencies in the future. The magnetic thin film material is expected to be highly expected. However, these researches and developments are still in their infancy, and there are still no reported examples of magnetic film materials having higher limit frequencies.

[0022]

As described above, the mobile phone, PHS, Bluetooth, wireless LAN, I
Although there are strong expectations for the practical application of high-frequency circuit inductors, transformers, and magnetic / dielectric hybrid transmission line devices in information communication equipment such as TS, the limit frequency due to ferromagnetic resonance is 5 in many current magnetic thin film materials.
The frequency remains below GHz, which greatly hinders the realization of the above-mentioned various high frequency devices. Further, there is a strong demand for realization of a thin film magnetic head for a hard disk drive capable of recording at a microwave band frequency on a high coercive force recording medium.

The present invention relates to a new magnetic thin film material having both a high ferromagnetic resonance frequency and a high saturation magnetization, and a high frequency device using these materials. It is an object of the present invention to provide a high frequency inductor for information communication equipment, a high frequency transformer, a magnetic / dielectric hybrid transmission line and a high frequency device using the same, and a thin film magnetic head for high frequency recording.

[0024]

In order to solve the above problems, a high frequency device of the present invention is characterized by having a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film, The metal thin film is formed from a material containing at least one of Fe, Co and Ni, a material containing an alloy thereof, or a multi-component alloy material containing these elements and other elements, and the antiferromagnetic oxide thin film is formed. Is
The laminated film includes any one of α-Fe ₂ O ₃ , CoO, and NiO, or a combination of two or more of these, and the laminated film includes a ferromagnetic metal magnetic thin film layer and an antiferromagnetic oxide. It is characterized in that thin film layers are alternately laminated in multiple layers.

According to a fifth aspect of the present invention, there is provided a high frequency planar inductor having a conductor film and a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film.

According to a sixth aspect of the present invention, there is provided a high frequency planar inductor including a laminated film magnetic core and a spiral coil.

According to a seventh aspect of the present invention, there is provided a high frequency planar inductor including a laminated film magnetic core and a zigzag coil.

A high-frequency planar inductor constructed by using a laminated film magnetic core and a solenoid coil wound around the magnetic core as described in claim 8.

According to a ninth aspect of the present invention, there is provided a high frequency planar transformer having a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film and a conductor coil.

According to a tenth aspect of the present invention, there is provided a high frequency planar transformer including a laminated film as a magnetic core and the magnetic core and a plurality of spiral coils.

Further, as described in claim 11, a high-frequency planar transformer configured by using a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film as a magnetic core and using the magnetic core and a plurality of zigzag coils. Is.

According to a twelfth aspect of the present invention, there is provided a planar transformer including the laminated film as a magnetic core and a plurality of solenoid coils wound around the magnetic core.

Further, according to a thirteenth aspect of the present invention, the transmission line is characterized by having a laminated film made of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film and a conductor line.

According to a fourteenth aspect, a microstrip line type transmission line is constructed by arranging the laminated film, a stripline located above the laminated film, and a ground electrode below the laminated film. .

According to a fifteenth aspect, a parallel line type transmission line is constructed by arranging the laminated film and a pair of parallel conductor lines above and below the laminated film.

According to a sixteenth aspect of the present invention, a pair of the laminated film and a conductor line are sandwiched by a pair of upper and lower laminated films, and an upper surface of the upper laminated film and a lower laminated film. An inner conductor line type transmission line is formed by disposing a ground electrode on the lower surface of the film.

According to a seventeenth aspect of the present invention, the high-frequency coplanar transmission is achieved by the laminated film, the strip line located above the laminated film, and the ground electrode located around the same plane of the strip line. The track is constructed.

A high frequency coplanar transmission line according to a seventeenth aspect of the present invention is configured so that a ground electrode located below the laminated film is provided.

Further, as described in claim 19, a high frequency resonator and a high frequency filter are constructed by using the stub in which the terminal of the transmission line according to claim 13 is shorted or opened.

Further, as described in claim 20, 1/4 is obtained by using the transmission line according to claim 13 to claim 18.
A wavelength transformer is constructed.

A high frequency transmission line filter using the ferromagnetic resonance of the laminated film is formed.

The transmission line may be a microstrip line type transmission line, a parallel line type transmission line, an internal conductor line type transmission line or a coplanar type transmission line, and the transmission line may be paired with the laminated film. And the conductor lines of the pair are arranged at positions where they are geometrically balanced and where the conductor lines are electromagnetically coupled to each other.

A distributed constant type common mode filter using the coupled transmission line according to the twenty-second aspect is constructed.

Further, according to a twenty-fourth aspect of the present invention, a thin film magnetic head for recording has a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film, and the laminated film is used as a recording yoke. To be done.

According to the high frequency device of the present invention, since the laminated film of the ferromagnetic metal film having a large saturation magnetization Ms and the antiferromagnetic oxide thin film is used, the ferromagnetic metal film is formed by the ferromagnetic / antiferromagnetic exchange coupling. A strong pinning effect acts on the magnetic domain of
Therefore, the effective anisotropic magnetic field Hk (eff.) In the hard axis direction is significantly increased, and coupled with the high saturation magnetization Ms, the ferromagnetic resonance frequency fr of the ferromagnetic metal film is significantly increased according to the formula (3) on the high frequency side. Shift to. As a result, the limit frequency of the magnetic material can be significantly increased, which provides an extremely effective means for increasing the frequency of the device. In addition, in the thin film magnetic head for recording, the recording characteristics on the high coercive force medium are improved by the ferromagnetic metal thin film having high saturation magnetization Ms.

According to the high frequency device of the present invention,
Since a laminated film of a ferromagnetic metal film and an insulating oxide is used, the high frequency eddy current generated by the in-plane AC magnetic field in the laminated film is significantly suppressed, which is extremely effective in reducing the high frequency loss of the device. Give a means.

According to the high frequency device of the present invention,
Since a laminated film of a ferromagnetic metal film and an antiferromagnetic oxide thin film is used, a magnetic substance / dielectric hybrid transmission line can be constructed by utilizing the action of the antiferromagnetic oxide thin film as a dielectric. Since the ferromagnetic resonance frequency is significantly increased by the ferromagnetic / antiferromagnetic exchange coupling, it provides an extremely effective means for increasing the frequency of the transmission line.

According to the present invention described above, there are provided a high frequency inductor having a GHz band as an operating frequency, a high frequency transformer, a magnetic / dielectric hybrid transmission line, a high frequency device using the transmission line, and a high frequency recording thin film magnetic head. realizable. These high frequency devices are used in mobile phones and P
It can be used for many systems such as information communication equipment such as HS, Bluetooth wireless LAN, ITS, and ultra high density hard disk drive.

[0049]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic structure of a high frequency inductor which is a first embodiment of the present invention. It has a structure in which the spiral coil 1 is sandwiched between upper and lower laminated film magnetic cores 2 and 3, and is called a spiral coil type planar inductor. The high frequency inductor shown in FIG.
Is manufactured through a thin film deposition process, photolithography, and etching. In the high frequency inductor according to the present invention, by using the exchange-coupling laminated film magnetic core 7 formed of the ferromagnetic metal magnetic film 5 and the antiferromagnetic oxide thin film 6, the ferromagnetic resonance frequency can be increased and the limit frequency of the inductor can be significantly increased. can do. The upper and lower magnetic cores 2 and 3 shown in FIG. 1 are composed of a laminated film 7 of a ferromagnetic metal film 5 and an antiferromagnetic oxide thin film 6, and an easy axis of magnetization in unidirectional magnetic anisotropy of the ferromagnetic metal thin film by exchange coupling. Y is induced as shown. Further, as shown in a partially enlarged cross-sectional view (c) of the laminated film magnetic core in FIG. 1, the lowermost layer and the uppermost layer 8 of the magnetic core are configured to be antiferromagnetic oxide thin films. By forming the antiferromagnetic oxide thin films of the lowermost layer and the uppermost layer 8 of the magnetic core so as to be thicker than the inner antiferromagnetic oxide thin film layer, an insulator between the coil conductor 1 and the metal magnetic film is formed. Also, the parasitic capacitance of this portion can be reduced.

FIG. 2 schematically shows the coil current and magnetic flux flow 9 of the spiral coil type planar inductor shown in FIG.

FIG. 3 shows a basic structure of a high frequency inductor which is a second embodiment of the present invention. The coil has the same laminated structure as that of the high-frequency inductor shown in FIG. 1 except that the coil has a zigzag pattern 11, and is referred to as a zigzag coil type planar inductor.

FIG. 4 schematically shows a coil current and a magnetic flux flow 19 of a split coil type planar inductor.

FIG. 5 shows a basic structure of a high frequency inductor which is a third embodiment of the present invention. Magnetic core 22 composed of a laminated film of a ferromagnetic metal film and an antiferromagnetic oxide thin film
The solenoid coil 21 is formed so as to be wound around, and is called a solenoid coil type planar inductor.
Similar to the high frequency inductors of FIGS. 1 and 2, the laminated film core 2
The lowermost layer and the uppermost layer of No. 2 are made of thick antiferromagnetic oxide thin films to maintain the insulation with the coil conductor and reduce the parasitic capacitance of this portion.

FIG. 6 schematically shows the coil current and magnetic flux flow 23 of the solenoid coil type planar inductor.

FIG. 7 shows the basic structure of a high frequency transformer according to a fourth embodiment of the present invention, in which two sets of spiral coils 26, 27 are sandwiched between upper and lower laminated film magnetic cores 25, 28. It is called a spiral coil type planar transformer. The two sets of spiral coils are shown in FIG.
It may be formed by stacking as shown in FIG.
As described above, two sets of spiral coils 29 and 30 may be placed on the same plane.

FIG. 8 shows the basic structure of a high frequency transformer according to a fifth embodiment of the present invention, in which two sets of meandering coils 36 and 37 are sandwiched by upper and lower laminated film magnetic cores 35 and 38. And has a zigzag coil type planar transformer. Two sets of winding coils are shown in FIG.
It may be configured by stacking as in (a) or may be configured by placing two sets of zigzag coils 39, 40 on the same plane as in FIG. 8 (b).

FIG. 9 shows the basic structure of a high frequency transformer according to a sixth embodiment of the present invention. Two sets of solenoid coils 45, are arranged so as to wind around the laminated film magnetic core 47.
46 is formed and is called a solenoid coil type planar transformer.

The coil parasitic capacitance in the high frequency inductor and the high frequency transformer shown in FIGS. 1 to 9 is as shown in FIG.
As shown in 0, the electrostatic capacitance Cij between the adjacent coil conductors 51 and 52 and the electrostatic capacitance Ci between the coil conductors 51 and 52 and the ferromagnetic metal film 54 are included, and the unit length of the coil conductors 51 and 52 is included. The electrostatic capacitance per hit is expressed by the following equations. Cij = εtc / s (F / m) (8) Ci = εw / td (F / m) (9) ε is the dielectric constant of the insulating film, tc and w are the thickness and width of the coil conductor, and s
Is the spacing between adjacent coil conductors, and td is the film thickness of the insulating film immediately above and below the coil conductor.

In a planar inductor or a planar transformer, in general, tc << s and w >> td are common in many cases. Therefore, from the relationship of Ci >> Cij, the coil parasitic capacitance is dominated by the electrostatic capacitance Ci between the coil conductor and the ferromagnetic metal film. In the present invention, the thickness td of the antiferromagnetic oxide thin film on the surface in contact with the coil conductor is increased to reduce the parasitic capacitance Ci at this portion,
Reduce the effect of self-resonance. Specifically, the film thickness td of the antiferromagnetic oxide thin film closest to the coil conductor needs to be determined in consideration of the signal frequency. The self-resonant frequency, which is determined by the device inductance and parasitic capacitance Ci, is anti-strength in consideration of the coil conductor width w so that it is at least twice as high as the limit frequency (ferromagnetic resonance frequency fr) of the laminated film magnetic core. It is desirable to determine the film thickness td of the magnetic oxide thin film.

The high-frequency inductor and the high-frequency transformer using the exchange-coupling laminated film magnetic core made of the ferromagnetic metal magnetic film and the antiferromagnetic oxide thin film are not limited to the device configurations described in the present text, and various structures are applicable. Needless to say, it is also extremely effective for increasing the limit frequency of the device even in the case of having.

An example of a high frequency inductor manufactured by using the exchange coupling laminated film magnetic core will be described below with reference to FIG. A multilayer film 67 made of a NiFe alloy film 65 having a thickness of 10 nm and a NiO film 66 having a thickness of 60 nm was produced by using a multi-source sputtering apparatus, and a spiral coil type planar inductor was produced by using the laminated film 67. The upper and lower laminated film magnetic cores 62 and 63 of the inductor are composed of 10 layers of NiFe alloy film 65 and 9 layers of NiO intermediate film 66. The spiral coil 61 is composed of a copper conductor pattern having a thickness of 3 μm, a width of 20 μm, a spacing of 20 μm and a coil turn number = 4, and is manufactured by photolithography and ion milling. As the insulating film between the lower laminated film magnetic core 63 and the coil conductor 61, a 1 μm thick NiO oxide film 68 was used.
Further, a NiO oxide film is formed by a bias sputtering method for the purpose of flattening the steps of the coil conductor, and the N
The thickness of the iO insulating film was 1 μm. The prototyped planar inductor has an outer size of 500 μm square.

FIG. 12 shows that the manufactured NiFe / NiO exchange coupling laminated film has the same total thickness as the NiFe film.
7 shows the measurement result of a static magnetization curve in the hard axis direction Y of a 0 nm thick NiFe single layer film. In this figure, in order to see the effect of exchange coupling, the thickness of the antiferromagnetic film in the laminated film is not counted, but the magnetization is converted by the total thickness of the NiFe film. As can be seen from the figure, the saturation magnetic field of the single layer film is about 640 A / m (8 Oe), whereas that of the laminated film is about 18000 A / m (225 Oe), which is due to exchange coupling with the NiO film. It can be seen that the apparent anisotropic magnetic field is greatly increased.

FIG. 13 shows the frequency characteristics of the magnetic permeability in the direction of the hard axis of the manufactured NiFe / NiO exchange-coupling laminated film and the NiFe single-layer film having a thickness of 100 nm.
The magnetic resonance frequency of the single-layer film was about 800 MHz, whereas in the case of the laminated film, the magnetic resonance frequency was about 4.2 GHz although the magnetic permeability decreased.

FIG. 14 shows the frequency characteristic of the inductance of the manufactured planar inductor. In the structure in which the coil is sandwiched with the magnetic material, the effect of increasing the inductance with respect to the air core does not largely depend on the magnetic permeability of the magnetic material due to the magnetic air gap effect between the upper and lower magnetic materials. Actually, the value of the low-frequency inductance is no more than double when the NiFe single layer film having high magnetic permeability is used and when the laminated film having low magnetic permeability is used. However, the cutoff frequency of the inductance when using a single-layer film is around 1 GHz, whereas that when using a laminated film reaches up to about 4 GHz, and the exchange-coupling laminated film has a wider band for planar inductors. It turns out that the adoption of is extremely effective.

FIG. 15 shows the structure of the high frequency transmission line according to the seventh embodiment of the present invention. An exchange-coupling laminated film 72 in which a ferromagnetic metal film and an antiferromagnetic oxide thin film are alternately laminated, a strip line 71 located above the laminated film, and a ground electrode 73 located below the laminated film. Type transmission line is constructed. The microstrip line type transmission line shown in FIG. 15 uses an appropriate substrate,
It is manufactured through a thin film deposition process, photolithography, and etching.

By constructing a transmission line by using a laminated body in which ferromagnetic metals and dielectrics are alternately laminated, the distributed capacitance Co due to the dielectric and the distributed inductance Lo increased due to the magnetic material are combined to obtain a wavelength shortening effect. It is remarkably increased (see the equation (5)), and it is extremely effective for miniaturization of the device by shortening the line length. Further, in the present invention, the ferromagnetic oxide thin film can be used for exchange coupling with the ferromagnetic metal film, and at the same time, it can be expected to act as a dielectric. Therefore, by increasing the ferromagnetic resonance frequency as described above, the microstrip line can be used. The applied frequency of the type transmission line can be significantly increased. By setting the easy axis Y in the unidirectional magnetic anisotropy of the ferromagnetic metal thin film induced by exchange coupling in the longitudinal direction of the strip line as shown in the figure, the magnetization is performed with respect to the high frequency magnetic field orthogonal to the line current. A magnetization rotation mode by hard axis excitation can be used.

FIG. 16 schematically shows the state of the internal electromagnetic field of the microstrip line type transmission line according to the present invention. The high frequency electric field 88 generated by the input voltage signal 87 applied between the strip line 81 and the ground electrode 84 is concentrated in the antiferromagnetic dielectric 83 because the ferromagnetic layer has high conductivity. On the other hand, stripline 8
The high-frequency magnetic flux 89 generated by the high-frequency current 86 flowing through 1 concentrates in the ferromagnetic layer 82. The propagation characteristics of the high frequency electromagnetic field are greatly affected by the interaction between both the magnetic substance and the dielectric substance.

FIG. 17 shows the structure of the high frequency transmission line according to the eighth embodiment of the present invention. A parallel line type transmission line is constructed by arranging a pair of parallel conductor lines 91 and 93 above and below the laminated film 92. It has the same basic structure as the microstrip line type transmission line shown in FIG. 15 except that the lower conductor 93 of the laminated film is processed into a conductor line shape.

FIG. 18 shows the structure of the high frequency transmission line according to the ninth embodiment of the present invention. The conductor line 101 in which the insulating film 102 is arranged on both sides is the upper and lower laminated films 103 and 104.
And a top surface of the laminated film on the top,
The ground electrodes 105 and 106 are arranged on the lower surface of the lower laminated film to form an internal conductor line type transmission line.

FIG. 19 schematically shows the state of the internal electromagnetic field of the internal conductor line type transmission line according to the present invention. In this transmission line, an electric field and a magnetic field are formed in the laminated films 103 and 104 above and below the conductor line 101. A high-frequency electric field is generated from the conductor line 101 in the directions of the upper and lower ground electrodes 105 and 106 in both the upward and downward directions, and the distributed capacitance Co between the conductor line and the ground electrode is parallel to the components of the upper and lower antiferromagnetic dielectrics. It is composed of connections, compared to microstrip lines and parallel lines, etc.
Co increases. In addition, the upper and lower exchange coupled laminated films 10
With the configuration of 3, 104, the high frequency magnetic flux density can be increased and the distributed inductance Lo can be increased. The greatest feature of the inner conductor line type transmission line is that the wavelength shortening effect can be remarkably increased by large Lo and Co.

FIG. 20 shows the structure of a high frequency transmission line according to the tenth embodiment of the present invention. An exchange coupling laminated film 113,
Strip line 11 located above the laminated film 113
The ground electrodes 115 and 116 are arranged around the same surface of 1 and the strip line 111 to form a coplanar transmission line.

FIG. 21 shows the structure of a high frequency transmission line according to an eleventh embodiment of the present invention. A ground electrode 117 is also disposed below the exchange-coupling laminated film 123 of the high-frequency coplanar transmission line shown in FIG. 20 to form a coplanar transmission line.

Several examples of the high frequency transmission line constructed by using the exchange coupling laminated film will be described in detail below. FIG. 22 shows the structure of a high-frequency resonator using an open-ended stub (a) or a short-circuited stub (b) using the high-frequency transmission line according to the twelfth embodiment of the present invention. In FIG. 22, the transmission line is illustrated in a simplified manner. The structure of the transmission line used for the stub is appropriately selected from various structures.

FIG. 23 shows the relationship between the input impedance Z and the frequency f of the terminating short circuit stub and the terminating open stub. In fo in the figure, the line length l is 1 / of the line wavelength λg.
The frequency is equal to 4 and is referred to herein as the fundamental frequency of the resonator. Input impedance Z of terminating short circuit stub
Takes a steep maximum value at a frequency that is an odd multiple of fo, and has a minimum value at a frequency that is an even multiple of fo. Therefore, the terminating short-circuit stub can be used as a resonator in which the impedance has a maximum value at the fundamental frequency fo and a frequency that is an odd multiple thereof. On the other hand, the input impedance Z of the open stub shows a steep minimum value at a frequency that is an odd multiple of fo, and has a maximum value at a frequency that is an even multiple of fo. Therefore, the open-ended stub can be used as a resonator having a minimum impedance at a frequency that is an odd multiple of the fundamental frequency fo. When the resonator is configured using the transmission line stub according to the present invention, the limiting frequency fr of the laminated film needs to be sufficiently higher than the fundamental frequency fo of the resonator, and even in that case, the available overtone frequency is Note that is limited by fr.
Also, in general, as the frequency increases, the line loss increases, so the unloaded Q of the resonator decreases, which also limits the available overtone frequency.

FIG. 24 shows a configuration example of the band pass filter (a) and the band stop filter (b) constructed by using the terminating short circuit stub and the terminating open stub described in FIG. When these stubs are lossless, a filter characteristic that repeats at the fundamental frequency fo and a frequency that is an odd multiple of that is obtained, but due to the limit frequency of the laminated film and high-frequency line loss, the filter characteristic gradually increases at frequencies higher than fo. It deteriorates. However, the signal band is 2 with the fundamental frequency fo
It is sufficiently possible to use these stubs as a band pass filter and a band stop filter having a center frequency of fo as long as the range does not exceed twice.

FIG. 25 shows the construction of a quarter wavelength transformer using a high frequency transmission line according to a thirteenth embodiment of the present invention. In FIG. 25, the transmission line is shown in a simplified manner. The structure of the transmission line used for the quarter-wave transformer is appropriately selected from various structures. The quarter-wave transformer is
It is often used as an impedance matching circuit in a high frequency circuit, and is used by inserting it between a signal source having a signal source impedance Zs and a load having an impedance ZL. If the characteristic impedance of the transmission line is Zo and the propagation constant is γ, the input impedance Zin of the transmission line terminated by the load ZL is given by equation (10),

[0078]

[Equation 8]

In particular, Zin at the frequency fo at which the line length l is equal to ¼ of the line wavelength λg is expressed by the equation (11).

[0080]

[Equation 9]

If the 1/4 wavelength frequency fo of the transmission line is made to coincide with the signal frequency fs and the characteristic impedance Zo is designed so that the input impedance Zin of the 1/4 wavelength transformer becomes equal to the signal source impedance Zs, Impedance matching between the signal source and the load can be achieved. When both the signal source impedance Zs and the load impedance ZL are complex impedances and are expressed by the following equation, Zs = Rs + j Xs (12) ZL = RL + j XL (13)

As shown in FIG. 26, a series reactance satisfying the following equation is established on the input side and the output side of the quarter wavelength transformer.
When X1 and X2 are connected,

X1 = -Xs (14) X2 = -XL (15)

The apparent signal source impedance Zs 'and the load impedance ZL' seen from the 1/4 wavelength transformer can be regarded as pure resistances Rs and RL.

[0085]     Zs' = Rs + j (Xs + X1) ≈ Rs (16)     ZL '= RL + j (XL + X2) ≈ RL (17)

From equation (11), conjugate matching can be realized by setting the characteristic impedance Zo of the quarter wavelength transformer according to equation (18).

[0087]

[Equation 10]

As described above, the quarter-wave transformer using the high-frequency transmission line according to the present invention can be used for an impedance matching circuit of a high-frequency circuit, and by adopting a laminated film having a high limit frequency, It enables application at higher frequencies. Further, the series reactances X1 and X2 for conjugate matching may be configured by using fixed inductors or fixed capacitors, or termination short-circuit stubs and termination open stubs using transmission lines may be used. The terminating short circuit stub using the transmission line can be used as an inductive reactance (X> 0) at a frequency lower than the fundamental frequency fo, and the open stub can be used as a capacitive reactance (X <0).

More specifically, as shown in FIG. 27, 1/4
If the line length of the stub is shorter than that of the wavelength transformer,
Signal frequency impedance matched by wavelength transformer
In fs, these stubs can be used as reactance elements. Since the stub and the quarter-wave transformer can be manufactured by the same transmission line manufacturing process, the thin film process can realize a one-chip device in which these devices are integrated.

FIG. 28 shows a high frequency transmission line type filter characterized by using the ferromagnetic resonance phenomenon which is the 14th embodiment of the present invention. The filter uses the ferromagnetic resonance phenomenon of an exchange-coupling laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film. Although the microstrip line type is shown in FIG. 28, it can be used for other transmission line structures. The present invention provides a low-pass filter having a steep attenuation characteristic by utilizing a magnetic loss that rapidly increases near the ferromagnetic resonance frequency fr of a magnetic material. The operation of the high frequency filter utilizing the ferromagnetic resonance phenomenon will be described with reference to a prototype of a microstrip line type transmission line using a NiFe / NiO exchange coupling laminated film. The NiFe / NiO exchange-coupling laminated film is the same as that shown in FIGS. 11 to 14.

FIG. 29 shows the frequency dependence of the real part μs ′ and the imaginary part μs ″ of the complex relative permeability μs * of the NiFe / NiO exchange coupling laminated film. Μs * is (19) It is defined by the formula: μs * = μs'− j μs ”(19)

As is apparent from FIG. 29, the ferromagnetic resonance frequency fr is about 4.2 GHz, and μs ′ is inverted from a positive value to a negative value at this frequency, and μs ″ corresponding to magnetic loss.
Suddenly increases at the resonance point.

FIG. 30 shows the measurement results of the transmission coefficient S21 and the reflection coefficient S11 of the S parameters of the microstrip line type transmission line using the NiFe / NiO exchange coupling laminated film. The microstrip line transmission line is designed so that the characteristic impedance is 50Ω in the low pass band lower than the frequency fr, and the S parameter is also measured in the 50Ω system. As is apparent from FIG. 30, the transmission coefficient S21 is almost 0 dB up to a frequency of about 4 GHz, and the reflection coefficient S11 is also sufficiently small. Therefore, in the low frequency range lower than the frequency fr, the insertion loss with respect to the input signal is small, and the reflection at the input end can be almost ignored. Further, it can be seen that the insertion loss sharply increases at the frequency fr and the high-frequency attenuation characteristic per unit length of the line reaches 10 dB / mm / dec. A detailed analysis reveals that the steep high-frequency attenuation characteristic with the frequency fr as a boundary is caused by a rapid increase in magnetic loss due to ferromagnetic resonance.

According to the present invention, a high frequency filter having a steep high frequency attenuation characteristic can be realized by a simple transmission line structure. Further, as will be described later, the ferromagnetic resonance frequency fr of the exchange-coupling laminated film can be changed by the combination of the materials of the ferromagnetic metal and the antiferromagnetic oxide, or by the film thickness ratio of both. It is possible to realize a high frequency filter having various cutoff frequencies. Although not described in detail here, since the resonance frequency fr can be changed by applying a DC bias magnetic field to the exchange coupling laminated film, a tunable high frequency filter can be realized.

FIG. 31 is a combined transmission line according to the fifteenth embodiment of the present invention, which is provided with a plurality of conductor lines 141 and 142 and is arranged at a position where the conductor lines are coupled to each other. This is an outline. Ferromagnetic metal film /
An exchange coupling laminated film 143 made of an antiferromagnetic oxide film is a microstrip line type transmission line arranged between the lower ground electrode 144 and the conductor lines 141 and 142. Although not described in detail here, the coupling lines 141 and 142 may be configured using transmission lines of other structures. In recent high frequency circuits, signals are increasingly transmitted in a balanced mode from the viewpoint of suppressing electromagnetic interference problems. According to the coupled transmission line of the present invention, a compact and wide-band balanced mode transmission line can be constructed by shortening the line length by the magnetic substance / dielectric hybrid and increasing the critical frequency by the exchange coupling laminated film.

FIG. 32 shows an outline of a distributed constant type common mode filter which is a sixteenth embodiment of the present invention, and the basic constitution is the same as that of the internal conductor line type transmission line shown in FIG. Yes, the only difference is that a pair of conductor lines 151, 152 are provided. Although not described in detail here, the distributed constant type common mode filter may be configured using a transmission line having another structure. Recently, balanced mode digital signal transmission such as USB and IEEE 1394 interface has begun to spread as a signal interface between digital devices. Balanced mode signal transmission is a pair of lines 15
Since the high-frequency currents flowing through 1, 152 have opposite phases, electromagnetic noise to the outside world is small, and resistance to electromagnetic noise from the outside world is high. However, it is difficult to perfectly balance the signal source, and a large amount of electromagnetic noise is radiated when an unbalanced signal component (common-mode current component) propagates through the line. The common mode filter has a function of passing a balanced mode signal and blocking an unbalanced mode component, and a common mode choke using a magnetic material is used as a typical device. However, a conventional common mode choke using a magnetic material cannot exhibit its function at a high frequency exceeding GHz. The distributed constant type common mode filter according to the present invention reduces the line length by a magnetic substance / dielectric hybrid,
By increasing the limit frequency by the exchange-coupling laminated film,
A compact and wideband common mode filter can be constructed.

FIG. 33 shows the equivalent circuit of the distributed constant type common mode filter as a coupled distributed constant circuit. Although detailed description is omitted, it is important to make the magnetic coupling between the two sets of conductor lines dense (coupling coefficient k≈1), and in this respect, the internal conductor line type is suitable for the transmission line structure.

FIG. 34 is a schematic view of a high frequency recording thin film magnetic head according to a seventeenth embodiment of the present invention. In current thin-film magnetic heads for hard disk drives, a read head using a spin valve or a tunnel MR and a recording head are generally integrated, but in FIG. Omitted. In this structure, the exchange-coupling laminated films 161, 162, 164 for the recording yoke and the coil 163 are arranged as shown in the figure. An exchange-coupling laminated film 164 is formed by laminating a ferromagnetic metal thin film 166 having a high saturation magnetization Ms and antiferromagnetic oxide thin films 165 and 167 (see FIG. 35). By adopting the exchange-coupling laminated films 161 and 162 in the recording head, it is expected that the magnetic field generated by the head is increased, the limiting frequency of the ferromagnetic metal thin film is increased, and the eddy current is suppressed. Will be possible.

In the exchange-coupling laminated film used in various high frequency devices of the present invention, the ferromagnetic metal magnetic thin film is
Fe, Co, one of Ni, or formed using these alloy or multicomponent alloy materials containing these and other elements, anti-ferromagnetic oxide thin film alpha-Fe ₂
An exchange-coupling laminated film is formed by alternately laminating ferromagnetic metal magnetic thin films and antiferromagnetic oxide thin films containing any one of O ₃ , CoO, and NiO, or those containing two or more of them. The specific structure of the exchange-coupling laminated film will be described below.

As shown in FIG. 35, since the ferromagnetic layer 166 of the exchange-coupling laminated film is sandwiched by the antiferromagnetic layers 165 and 67, the exchange is performed at two places, the upper interface and the lower interface of the magnetic layer. Coupling occurs, and the exchange-coupling magnetic field Hex (unit: A / m) that acts on the magnetic layer at this time is expressed by the equation (20).

[0101]

[Equation 11] Where Jex is the exchange coupling energy per unit area of the interface (unit: J / m2), MF is the saturation magnetization of the ferromagnetic layer (unit: T), and tF is the thickness of the ferromagnetic layer (unit: m). is there. In the exchange-coupling laminated film according to the present invention, the magnetization reversal with respect to the external magnetic field must be made to occur only in the ferromagnetic layer, and for that purpose, the magnetic anisotropy energy of the antiferromagnetic layer is larger than the exchange coupling energy. Is required.
Specifically, since exchange coupling energy is generated at the two interfaces of the antiferromagnetic layer, the condition is that the magnetic anisotropy energy is larger than the total of 2Jex in the above equation.
That is, the condition of KAF × tAF> 2Jex (21) is imposed. Here, KAF is the magnetic anisotropy constant of the antiferromagnetic layer (unit: J / m3), and tAF is the film thickness of the antiferromagnetic layer (unit: m).

Since the exchange coupling magnetic field Hex gives a measure of the effective anisotropic magnetic field Hk (eff.) Of the ferromagnetic layer, (20)
In the formula, if Hex is replaced with Hk (eff.) And transformed,
The thickness tF of the ferromagnetic layer is given by the equation (22).

[Equation 12]

The critical film thickness tAF0 of the antiferromagnetic layer for satisfying the condition of expression (21) is expressed by expression (23).

[Equation 13] That is, in order to cause magnetization reversal only in the ferromagnetic layer with respect to the external magnetic field, the thickness tAF of the antiferromagnetic layer is set to the critical thickness tAF0.
Need to be larger than.

A configuration example of the exchange-coupling laminated film in the case where a microstrip line type 1/4 wavelength transformer is prototyped for the purpose of being applied to a high frequency circuit of a 1.9 GHz band wireless LAN device will be described. The exchange-coupling laminated film is Ni80Fe20 as a ferromagnetic metal thin film and N as an antiferromagnetic oxide thin film.
iO was used. The exchange coupling energy Jex of Ni80Fe20 / NiO is estimated to be about 9 × 10 ⁻⁵ (J / m ² ), and
The saturation magnetization MF of the Ni80Fe20 film was about 1T. Ni80Fe20 Induced Unidirectional Magnetic Anisotropy by Exchange Coupling
On the other hand, in order to set the ferromagnetic resonance frequency fr of the magnetization rotation to 4 GHz which is more than twice the signal frequency, the value of the effective anisotropic magnetic field Hk (eff.) Of Ni80Fe20 due to the exchange coupling bias is set to 1
It should be about 6000 A / m (200 Oe). When the film thickness tF of Ni80Fe20 was calculated using these values and the equation (22), it was about 11 nm. Further, the critical film thickness tAF0 of the antiferromagnetic NiO film which exhibits exchange coupling was about 60 nm.

[Ni80Fe20 (11nm) / NiO (60n
m)] as a unit and 30 layers were laminated, and the uppermost layer and the lowermost layer of the laminated film were NiO (60 nm) to form an exchange coupling laminated film. 1 μm as ground electrode for microstrip line
Thick Al conductor, stripline thickness 1 μm, width 5
A 0 μm Al conductor line was used. Device width is 500 μm
And The relative permittivity of the NiO film used as a dielectric was about 10, and the distribution capacitance Co per unit length of the line thus obtained was about 18 nF / m. In addition, ferromagnetic Ni
The distributed inductance Lo per unit length of the line enhanced by the 80Fe20 film was 320 nH / m. L
From the values of o and Co, the wavelength shortening rate for the free space wavelength was about 1/23, and the line length was 1.72 mm in order to configure a quarter wavelength transformer for signals in the 1.9 GHz band. A matching circuit was arranged between the signal source impedance of the former circuit of 1.8Ω and the input impedance of the latter circuit of 10Ω, and as a result of applying this to the matching circuit, normal operation as an impedance converter was confirmed.

Here, an example of the 1.9 GHz band microstrip line type transmission line using the Ni80Fe20 / NiO exchange-coupling laminated film has been described. However, in order to utilize it for a higher signal frequency, a high saturation magnetization is used. A combination of a ferromagnetic metal film and a ferromagnetic / antiferromagnetic exchange coupling capable of expressing a large exchange coupling bias magnetic field may be used.
For example, as a ferromagnetic metal film, it is conceivable to apply Fe or Co alone having a large saturation magnetization Ms, an alloy material thereof, or various alloy materials containing Ni and other additive elements. With these techniques, it is possible to realize a ferromagnetic resonance frequency exceeding 5 GHz, which is rarely seen in the past. In either case, the exchange coupling energy, the saturation magnetization of the ferromagnetic metal film, the magnetic anisotropy energy of the antiferromagnetic film, etc. differ depending on the type of the ferromagnetic metal film or the antiferromagnetic oxide film. It goes without saying that it is necessary to design the exchange-coupling laminated film based on the above-mentioned guidelines.

[0107]

As described above in detail, according to the present invention, a mobile phone, PHS, PDA, Bluetooth,
This can greatly contribute to downsizing and widening of the band of high-frequency devices for various high-frequency circuits in information communication systems represented by wireless LAN and ITS equipment.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic structure of a spiral coil type planar inductor which is a first embodiment of the present invention,
(A) is a top view, (b) is an AA sectional view, and (c) is a partially enlarged sectional view.

FIG. 2 is a schematic diagram of a coil current and a flow of magnetic flux of a spiral coil type planar inductor.

FIG. 3 is a diagram showing a basic structure of a spirally coiled planar inductor according to a second embodiment of the present invention,
(A) is a top view, (b) is an AA sectional view, and (c) is a partially enlarged sectional view.

FIG. 4 is a schematic diagram of the coil current and the flow of magnetic flux of a split coil type planar inductor.

FIG. 5 is a diagram showing a basic structure of a solenoid coil type planar inductor which is a third embodiment of the present invention.

FIG. 6 is a schematic diagram showing the flow of coil current and magnetic flux of a solenoid coil type planar inductor.

FIG. 7 is a diagram showing a basic structure of a spiral coil type planar transformer according to a fourth embodiment of the present invention, (a)
Is a laminated spiral coil type, and (b) is a multiple spiral coil type.

FIG. 8 is a diagram showing a basic structure of a zigzag coil type planar transformer according to a fifth embodiment of the present invention, FIG.
Is a laminated zigzag folded coil type, and (b) is a multiple zigzag folded coil type.

FIG. 9 is a diagram showing a basic structure of a solenoid coil type planar transformer which is a sixth embodiment of the present invention.

FIG. 10 is a schematic diagram of the electrostatic capacitance between adjacent coil conductors and the electrostatic capacitance between the coil conductor and the ferromagnetic metal film in the high frequency devices of the first to sixth embodiments of the present invention.

FIG. 11 is a diagram showing a configuration of a spiral coil type planar inductor using a NiFe / NiO exchange coupling laminated film formed of a NiFe alloy film and a NiO film according to the first embodiment of the present invention.

FIG. 12 is a NiFe / NiO exchange coupling laminated film and NiF.
It is a figure which shows the static magnetization curve of the hard axis direction of a NiFe single layer film with the same total thickness of e film.

FIG. 13: NiFe / NiO exchange coupling laminated film and NiFe
It is a figure which shows the frequency characteristic of the magnetic permeability of the single layer film | membrane in the hard-axis direction.

FIG. 14 is a diagram showing frequency characteristics of inductance of a spiral coil type planar inductor.

FIG. 15 is a diagram showing a basic structure of a microstrip line type transmission line according to a seventh embodiment of the present invention.

FIG. 16 is a schematic diagram of an internal electromagnetic field of a microstrip line type transmission line.

FIG. 17 is a diagram showing a basic structure of a parallel line type transmission line according to an eighth embodiment of the present invention.

FIG. 18 is a diagram showing a basic structure of an internal conductor line type transmission line according to a ninth embodiment of the present invention.

FIG. 19 is a schematic diagram of an internal electromagnetic field of an internal conductor line type transmission line.

FIG. 20 is a diagram showing the basic structure of a coplanar transmission line that is a tenth embodiment of the present invention.

FIG. 21 is a diagram showing the basic structure of a coplanar transmission line that is an eleventh embodiment of the present invention.

FIG. 22 is a diagram showing a basic configuration of a termination short-circuit stub or a termination open stub using a transmission line used in a high frequency resonator according to a twelfth embodiment of the present invention;
Is a basic configuration of the termination open stub, and (b) is a termination short-circuit stub.

FIG. 23 is a diagram showing the relationship between the input impedance Z and the frequency f of the termination short-circuit stub and termination termination stub.

FIG. 24 is a diagram showing a configuration example of a bandpass filter and a bandstop filter configured by using a terminating short circuit stub and a termination stub, (a) is a configuration example of a bandpass filter, and (b) is a diagram. 2 is a configuration example of a band elimination filter.

FIG. 25 is a diagram showing a basic configuration of a ¼ wavelength transformer using a transmission line that is a thirteenth embodiment of the present invention.

FIG. 26 is a configuration example in the case where conjugate impedance matching is applied to FIG. 25.

FIG. 27 is a specific configuration example in which conjugate impedance matching is applied using termination short-circuit stubs and termination termination stubs.

FIG. 28 is a diagram showing a basic configuration of a microstrip line type transmission line filter which is a fourteenth embodiment of the present invention.

FIG. 29 is a diagram showing frequency characteristics of complex relative permeability of a NiFe / NiO exchange coupling laminated film used for a microstrip line type transmission line filter.

FIG. 30 is a diagram showing measurement data of S parameters of a microstrip line type transmission line filter using a NiFe / NiO exchange coupling laminated film.

FIG. 31 is a diagram showing the structure of a coupled transmission line including a pair of conductor lines according to a fifteenth embodiment of the present invention.

FIG. 32 is a diagram showing the structure of a distributed constant type common mode filter that is a sixteenth embodiment of the present invention.

FIG. 33 is a diagram showing an equivalent circuit of a distributed constant type common mode filter.

FIG. 34 is a diagram showing the structure of a thin film magnetic head for high frequency recording which is a seventeenth embodiment of the present invention.

FIG. 35 is a diagram showing a basic structure of an exchange-coupling laminated film used in a high-frequency device according to first to seventeenth embodiments of the present invention.

FIG. 36 is a diagram showing a circuit configuration example of a conventional PHS RF amplifier MMIC module.

FIG. 37 is a chip photograph of a conventional PHS RF amplifier MMIC module.

FIG. 38 is a diagram showing a structural example of a conventional RF magnetic thin film inductor for a mobile phone.

FIG. 39 is a diagram showing a basic structure of a conventional microstrip line type transmission line.

FIG. 40 is a diagram showing a basic structure of a conventional coplanar transmission line.

FIG. 41 is a diagram showing a circuit configuration example of a conventional 50 GHz band low noise amplifier.

FIG. 42 is a diagram showing a distributed constant type equivalent circuit of a transmission line.

FIG. 43 is a diagram showing a configuration example of a conventional thin film magnetic head for magnetic recording.

FIG. 44 is a diagram showing a magnetization curve of a [FeTaN (20 nm) / IrMn (10 nm)] exchange coupling laminated film.

FIG. 45 is a diagram showing frequency characteristics of complex magnetic permeability of [FeTaN (20 nm) / IrMn (10 nm)] exchange coupling laminated film.

[Explanation of symbols]

1 spiral coil 2, 12 upper laminated film, upper exchange coupled laminated film magnetic core 3, 13 upper laminated film, lower exchange coupled laminated film magnetic core 4, 14 substrate 5,15 Ferromagnetic metal film 6,16 Antiferromagnetic oxide film 7,17 Exchange coupled laminated film 8,18 Top layer of magnetic core 9, 19 magnetic field 11 zigzag coil 21 solenoid coil 22 Exchange-coupling laminated film magnetic core 23 magnetic field 24 substrates 25, 31 Upper exchange coupled laminated film magnetic core 26,29 Primary spiral coil 27,30 Secondary spiral coil 28, 32 Lower exchange coupled laminated film magnetic core 33,34 magnetic field 35,41 Upper exchange coupled laminated film magnetic core 36,39 Primary winding coil 37,40 Secondary winding coil 38,42 Lower exchange coupled laminated film magnetic core 45 primary solenoid coil 46 secondary solenoid coil 47 Exchange coupled laminated film magnetic core 51,52 coil conductor 53 Exchange coupled multilayer magnetic core 54 Ferromagnetic metal film 61 spiral coil 62 Upper Exchange Coupling Laminated Film Magnetic Core 63 Lower exchange-coupling laminated film magnetic core 64 substrates (glass substrate) 65 Exchange-Coupled Laminated Film Magnetic Core (NiFe Alloy
film) 66 Antiferromagnetic oxide film (NiO film) 67 Exchange coupled laminated film 68 Top layer of magnetic core (NiO film) 71 strip line 72 Exchange coupled laminated film 73 Ground electrode 74 board 81 strip line 82 Ferromagnetic metal film 83 Antiferromagnetic oxide film 84 Ground electrode 85 substrate 86 current 87 signal source 88 electric field vector 89 Magnetic flux density vector 91 Upper conductor line 92 Exchange coupled laminated film 93 Lower conductor line 94 substrates 101 conductor line 102 insulating film 103 exchange coupled laminated film 104 Exchange coupled laminated film 105 Upper ground electrode 106 Lower ground electrode 107 substrate 111 conductor line 113 Exchange coupled laminated film 115 Ground electrode 116 Ground electrode 118 substrate 121 conductor line 123 Exchange coupled laminated film 125 ground electrode 126 Ground electrode 127 Lower ground electrode 128 substrates 131 strip line 132 Exchange coupled laminated film 134 Ground electrode 135 substrate 141,142 Conductor line 143 Exchange coupled laminated film 144 Lower ground electrode 145 substrate 151,152 Conductor line 153 Upper ground electrode 154, 155 Exchange coupling laminated film 156 Lower ground electrode 157 substrate 161, 162, 164 Exchange coupling lamination for recording yoke
film 163 coil 165,167 Antiferromagnetic oxide layer 166 Ferromagnetic metal layer 171,176 Magnetic film 172 Underlayer 173 Polyimide 174 spiral coil 175 SiO_Two 177 Si 181,184 conductor lines 182 dielectric 183 Ground conductor 185 dielectric 186,187 Ground conductor 191,192 magnetic film for recording 193 coil 194 Spin valve read head 195 Shield layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshiro Sato             1-16-48-305 Wakasato Nagano City, Nagano Prefecture (72) Inventor Kiyoto Yamazawa             90 Joto, Matsushiro-cho, Nagano-shi, Nagano (72) Inventor Toshiyuki Sakuma             14016 Nakaminowa, Minowa-cho, Kamiina-gun, Nagano Prefecture             Inside Coer Co., Ltd. (72) Inventor Hiroki Karasawa             14016 Nakaminowa, Minowa-cho, Kamiina-gun, Nagano Prefecture             Inside Coer Co., Ltd. F-term (reference) 5E070 AA05 AB01 BA12 BB01 CB02                       CB13 CB14 CB15 EB01                 5J014 CA05

Claims (24)

[Claims] 1. A high-frequency device comprising a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film. 2. The ferromagnetic metal thin film is made of Fe, Co, N.
The high-frequency device according to claim 1, wherein the high-frequency device is formed of a material containing at least one of i, an alloy containing these, or a multi-component alloy material containing these and other elements. 3. The antiferromagnetic oxide thin film comprises α-Fe ₂
The high frequency device according to claim 1, comprising at least one of O ₃ , CoO, and NiO, or a combination of two or more of these. 4. The high frequency device according to claim 1, wherein the laminated film is formed by laminating a ferromagnetic metal magnetic thin film layer and an antiferromagnetic oxide thin film layer in multiple layers. 5. A high frequency planar inductor comprising a laminated film made of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film and a conductor coil. 6. The high frequency planar inductor according to claim 5, wherein the conductor coil is a spiral coil. 7. The high frequency planar inductor according to claim 5, wherein the conductor coil is a zigzag coil. 8. The high frequency planar inductor according to claim 5, wherein the conductor coil is a solenoid coil wound around the laminated film. 9. A high frequency planar transformer comprising a laminated film made of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film and a conductor coil. 10. The high frequency planar transformer according to claim 9, wherein the conductor coil is a plurality of spiral coils. 11. The high frequency planar transformer according to claim 9, wherein the conductor coil is a plurality of meandering coils. 12. The high frequency planar transformer according to claim 9, wherein the conductor coil is a plurality of solenoid coils wound around a magnetic core. 13. A transmission line comprising a laminated film made of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film and a conductor line. 14. The conductor line is a strip line, and is composed of a strip line located above the laminated film and a ground electrode located below the laminated film. Transmission line. 15. The conductor line is a pair of parallel conductor lines, and the pair of parallel conductor lines are arranged on an upper portion and a lower portion of the laminated film, respectively.
The transmission line according to item 3. 16. The laminated film is a pair of the laminated films, wherein a conductor line is sandwiched from above and below by the pair of the laminated films, and the upper surface of the upper laminated film and the lower laminated film are sandwiched. The transmission line according to claim 13, wherein a ground electrode is provided on the lower surface of the transmission line. 17. The transmission according to claim 13, comprising the laminated film, a strip line located above the laminated film, and a ground electrode located around the same plane of the strip line. line. 18. The transmission line according to claim 17, wherein a ground electrode is also formed below the laminated film. 19. A high-frequency resonator and a high-frequency filter having a terminating short-circuit stub and / or a terminating open stub using the transmission line according to any one of claims 13 to 18. 20. A quarter-wave transformer comprising the transmission line according to any one of claims 13 to 18. 21. A laminated film comprising a ferromagnetic metal thin film and an antiferromagnetic oxide thin film. A high-frequency filter using ferromagnetic resonance of the laminated film. 22. The transmission line is a microstrip line type transmission line, a parallel line type transmission line, an inner conductor line type transmission line or a coplanar type transmission line, and is composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film. A coupled transmission line, comprising a pair of conductor lines with a film, the pair of conductor lines being arranged at positions where they are geometrically balanced and where the conductor lines are electromagnetically coupled to each other. 23. A distributed constant type common mode filter using the coupling type transmission line according to claim 22. 24. A thin-film magnetic head for magnetic recording, comprising a laminated film composed of a ferromagnetic metal thin film and an antiferromagnetic oxide thin film, the laminated film being used as a recording yoke.