JP2021174808A - Magnetoresistance effective device - Google Patents

Abstract

To provide a magnetoresistance effective device capable of improving frequency selectivity.SOLUTION: This magnetoresistance effective device comprises a first port, a magnetoresistance effect element including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, a first high-frequency route, which is a high-frequency signal route between the magnetoresistance effect element and the first port, and a direct current application terminal which is connected to the magnetoresistance effect element and to which a power supply for applying a DC current or a DC voltage to the magnetoresistance effect element can be connected. The first high-frequency route or a second high-frequency route branched from the first high-frequency route includes a high-frequency magnetic field application unit arranged separated from the magnetoresistance effect element. A high-frequency magnetic field generated from a high-frequency current flowing inside the high-frequency magnetic field application unit is applied to the first ferromagnetic layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a magnetoresistive device.

In recent years, along with the sophistication of mobile communication terminals such as mobile phones, the speed of wireless communication has been increasing. Since the communication speed is proportional to the bandwidth of the frequency used, the frequency band required for communication is increasing. Along with this, the number of high-frequency components required for mobile communication terminals is also increasing.

In recent years, spintronics has been studied as a field that has the potential to be applied to new high-frequency components. Among them, the phenomena that are attracting attention are the ferromagnetic resonance phenomenon due to the magnetoresistive element and the oscillation phenomenon due to the spin transfer torque.

For example, Patent Document 1 describes an oscillator which is a high-frequency device utilizing an oscillation phenomenon due to spin transfer torque. The high frequency device is an example of a magnetoresistive device.

JP-A-2007-124340

Magnetoresistive devices are required to have improved frequency selectivity. A magnetoresistive device having excellent frequency selectivity has a large difference between the output characteristics in a specific frequency band and the output characteristics in other frequency bands. For example, an oscillator having a large difference in output characteristics between the oscillation band and other bands has excellent frequency selectivity.

The present invention has been made in view of the above problems, and provides a magnetoresistive effect device capable of improving frequency selectivity.

The following means are provided to solve the above problems.

(1) The magnetic resistance effect device according to the first aspect includes a first port to which a high-frequency signal is output, a first ferromagnetic layer, a second ferromagnetic layer, the first ferromagnetic layer, and the second ferromagnetic layer. A magnetic resistance effect element including a spacer layer sandwiched between the ferromagnetic layers, a first high frequency path which is a path of a high frequency signal between the magnetic resistance effect element and the first port, and the magnetic resistance effect. It is provided with a DC application terminal which is connected to the element and can connect a power source for applying a DC current or a DC voltage to the magnetic resistance effect element, and is provided with a first high frequency path or a second high frequency branched from the first high frequency path. The path has a high-frequency magnetic field application portion arranged apart from the magnetic resistance effect element, and a high-frequency magnetic field generated by a high-frequency current flowing inside the high-frequency magnetic field application portion is applied to the first ferromagnetic layer.

(2) In the magnetoresistive device according to the above aspect, the first high frequency path may have an amplifier between the magnetoresistive element and the high frequency magnetic field application unit.

(3) In the magnetic resistance effect device according to the above aspect, the first high frequency path may have an element portion between the magnetic resistance effect element and the high frequency magnetic field application portion, and the element portion may have an element portion. A second magnetic resistance effect element including a third ferromagnetic layer, a fourth ferromagnetic layer, and a second spacer layer sandwiched between the third ferromagnetic layer and the fourth ferromagnetic layer, and the first. The third ferromagnetic layer is a high-frequency magnetic field generated by a high-frequency current flowing inside the second high-frequency magnetic field application unit, which has a second high-frequency magnetic field application unit connected to or separated from the two magnetic resistance effect elements. The second magnetic resistance effect element is connected to the DC application terminal or the second DC application terminal to which a power source for applying a DC current or a DC voltage can be connected to the second magnetic resistance effect element. In the first high-frequency path, the second magnetic resistance effect element is located between the second high-frequency magnetic field application unit and the high-frequency magnetic field application unit.

(4) In the magnetoresistive device according to the above aspect, the second high frequency path may have a branch portion where the second high frequency path branches from the first high frequency path, and the second high frequency path may have the high frequency magnetic field application portion. ..

(5) In the magnetoresistive device according to the above aspect, an amplifier may be provided between the magnetoresistive element and the branch portion in the first high frequency path.

(6) In the magnetoresistive device according to the above aspect, an amplifier may be provided between the branch portion and the high frequency magnetic field application portion in the second high frequency path.

(7) In the magnetoresistive device according to the above aspect, between the magnetoresistive element and the branch portion in the first high frequency path, or between the branch portion and the high frequency magnetic field application portion in the second high frequency path. An attenuator may be provided between the two.

(8) In the magnetic resistance effect device according to the above embodiment, the magnetic resistance effect element and the branch portion in the first high frequency path, and the branch portion and the high frequency magnetic field application portion in the second high frequency path. An element portion may be provided in at least one of the spaces between the elements, and the element portion includes a third ferromagnetic layer, a fourth ferromagnetic layer, a third ferromagnetic layer, and a fourth ferromagnetic layer. It has a second magnetic resistance effect element including a second spacer layer sandwiched between the two, and a second high-frequency magnetic field application unit connected to or separated from the second magnetic resistance effect element. 2. A high-frequency magnetic field generated by a high-frequency current flowing inside the high-frequency magnetic field application portion is applied to the third ferromagnetic layer, and the second magnetic resistance effect element is subjected to a DC current to the DC application terminal or the second magnetic resistance effect element. Alternatively, when the first high frequency path is connected to a second DC application terminal to which a power source for applying a DC voltage can be connected and the first high frequency path has the element portion, the second magnetic resistance effect element is the first in the first high frequency path. 2 When the second high-frequency path is located between the high-frequency magnetic field application section and the branch portion and the second high-frequency path has the element section, the second magnetic resistance effect element is the second high-frequency magnetic field application section in the second high-frequency path. It is located between the high-frequency magnetic field application unit and the high-frequency magnetic field application unit.

The magnetoresistive device according to the above aspect can improve the frequency selectivity.

It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 1st Embodiment. It is a schematic diagram for demonstrating the operation of the magnetoresistive effect device which concerns on 1st Embodiment. It is a graph which shows an example of the relationship of the strength of the signal output from a magnetic resistance effect element with respect to the strength of the input signal passing through the high frequency magnetic field application part of the 1st high frequency path. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 1st modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 2nd Embodiment. It is a schematic diagram for demonstrating the operation of the magnetoresistive effect device which concerns on 2nd Embodiment. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 2nd modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 3rd modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 4th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 5th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 6th modification. It is a figure which shows typically the circuit structure of another example of the magnetoresistive effect device which concerns on 6th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 7th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 3rd Embodiment. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 8th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 9th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the tenth modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 11th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 12th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 13th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 14th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on 15th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 16th modification. It is a figure which shows typically the circuit structure of the magnetoresistive effect device which concerns on the 17th modification.

Hereinafter, the magnetoresistive device will be described in detail with reference to the drawings as appropriate. In the drawings used in the following description, the featured portion may be enlarged for convenience in order to make the feature easy to understand, and the dimensional ratio of each component may be different from the actual one. The materials, dimensions, etc. exemplified in the following description are examples, and the present invention is not limited thereto, and can be appropriately modified and carried out within the range in which the effects of the present invention are exhibited.

"First embodiment"
FIG. 1 is a diagram showing a circuit configuration of a magnetoresistive device according to the first embodiment. The magnetoresistive device 100 includes a magnetoresistive element 10, a first high frequency path 20, a DC application terminal 30, and a first port 31. The magnetoresistive device 100 shown in FIG. 1 also includes a line 16, a reference potential terminal 32, a frequency setting unit 90, an inductor 91, and a capacitor 93. The magnetoresistive device 100 operates by being connected to the power supply 92.

<Magnet Resistive Sensor>
The magnetoresistive element 10 includes a first ferromagnetic layer 1, a second ferromagnetic layer 2, and a spacer layer 3. The spacer layer 3 is located between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. Hereinafter, the stacking direction of the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the spacer layer 3 may be simply referred to as the “stacking direction”.

The first ferromagnetic layer 1 is, for example, a magnetization free layer (first magnetization free layer). The second ferromagnetic layer 2 is, for example, a magnetization fixed layer or a magnetization free layer (second magnetization free layer). The magnetization free layer is a layer made of a magnetic material whose magnetization direction changes when a predetermined external force is applied, and the magnetization fixed layer has a magnetization direction different from that of the magnetization free layer when a predetermined external force is applied. Is a layer made of a magnetic material that does not easily change. The predetermined external force is, for example, an external force applied to the magnetization by an external magnetic field or an external force applied to the magnetization by a spin polarization current. For example, the coercive force of the magnetized fixed layer is larger than the coercive force of the magnetized free layer. As an example, the direction of magnetization of the magnetization fixed layer is a direction parallel to the extending direction of the high-frequency magnetic field application portion 21 of the first high-frequency path 20 described later (the direction in which the high-frequency current flows inside the high-frequency magnetic field application portion 21). The vertical direction can be mentioned. The magnetic resistance effect element 10 causes a resistance value in the stacking direction (current flows in the stacking direction) according to a change in the relative angle between the magnetization direction of the first ferromagnetic layer 1 and the magnetization direction of the second ferromagnetic layer 2. (Reluctance value when this is done) changes. The second ferromagnetic layer 2 may be a fixed magnetization layer or a free magnetization layer as long as the relative angle of the magnetization direction of the first ferromagnetic layer 1 to the magnetization direction of the second ferromagnetic layer 2 changes.

The first ferromagnetic layer 1 and the second ferromagnetic layer 2 include a ferromagnetic material. For example, the first ferromagnetic layer 1 and the second ferromagnetic layer 2 can use a metal such as Cr, Mn, Co, Fe, or Ni, or an alloy containing one or more of these metal elements as a constituent material. Further, an alloy of the above metal element and at least one or more elements selected from B, C and N may be used. For example, the first ferromagnetic layer 1 and the second ferromagnetic layer 2 may have a CoFeB alloy as a main component when they function as a magnetization free layer.

The first ferromagnetic layer 1 and the second ferromagnetic layer 2, XYZ or X ₂ YZ intermetallic compound represented by the chemical composition (Heusler alloy) may be used. X is a transition metal element or a noble metal element of the group Co, Fe, Ni or Cu on the periodic table. Y is a transition metal of the group Mn, V, Cr or Ti or an element represented by X. Z is a typical element of groups III to V. For example, Co ₂ FeSi, Co ₂ MnSi, Co ₂ Mn _1-a Fe _a Al _b Si _1-b (0 ≦ a ≦ 1, 0 ≦ b ≦ 1) and the like are known as Whistler alloys.

An antiferromagnetic layer may be added so as to be in contact with the second ferromagnetic layer 2 so that the second ferromagnetic layer 2 functions as a magnetization fixing layer. Further, the magnetization of the second ferromagnetic layer 2 may be fixed by utilizing the magnetic anisotropy caused by the crystal structure, shape, and the like. For the antiferromagnetic layer, FeO, CoO, NiO, CuFeS ₂ , IrMn, FeMn, PtMn, Cr, Mn or the like can be used.

The spacer layer 3 is a non-magnetic layer arranged between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. The spacer layer 3 is composed of a layer composed of a conductor, an insulator or a semiconductor, or a layer including an energizing point formed of a conductor in the insulator.

For example, when the spacer layer 3 is made of an insulator, the magnetoresistive element 10 becomes a tunnel magnetoresistive (TMR) effect element, and when the spacer layer 3 is made of metal, it becomes a giant magnetoresistive (GMR). It becomes an effect element.

When the spacer layer 3 is made of an insulating material, a material such as aluminum oxide, magnesium oxide, titanium oxide or silicon oxide can be used. A high reluctance rate of change can be obtained by adjusting the film thickness of the spacer layer 3 so that a high TMR effect is exhibited between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. In order to efficiently utilize the TMR effect, the film thickness of the spacer layer 3 may be about 0.5 to 10.0 nm.

When the spacer layer 3 is made of a non-magnetic conductive material, a conductive material such as Cu, Ag, Au or Ru can be used. In order to efficiently utilize the GMR effect, the film thickness of the spacer layer 3 may be about 0.5 to 3.0 nm.

When the spacer layer 3 is made of a non-magnetic semiconductor material, a material such as zinc oxide, indium oxide, tin oxide, germanium oxide, gallium oxide or ITO can be used. In this case, the film thickness of the spacer layer 3 may be about 1.0 to 4.0 nm.

When a layer including a current-carrying point composed of a conductor in a non-magnetic insulator is applied as the spacer layer 3, CoFe, CoFeB, CoFeSi, ComnGe, and ComnSi are contained in the non-magnetic insulator composed of aluminum oxide or magnesium oxide. , ComnAl, Fe, Co, Au, Cu, Al, Mg, and other conductors, preferably have a structure including a current-carrying point. In this case, the film thickness of the spacer layer 3 may be about 0.5 to 2.0 nm.

In order to increase the electrical conductivity of the magnetoresistive element 10, electrodes may be provided on both sides of the magnetoresistive element 10 in the stacking direction. Hereinafter, the electrode provided at the upper part of the magnetoresistive element 10 in the stacking direction in FIG. 1 is referred to as an upper electrode 12, and the electrode provided at the lower part is referred to as a lower electrode 14. By providing electrodes on both end surfaces of the magnetoresistive element 10 in the stacking direction, the contact between each line and the magnetoresistive element 10 becomes a surface, and a signal can be obtained at any position in the in-plane direction of the magnetoresistive element 10. The flow of (current) follows the stacking direction.

The magnetoresistive sensor 10 may have other layers. For example, the magnetoresistive element 10 may have a seed layer or a buffer layer on the surface of the second ferromagnetic layer 2 opposite to the first ferromagnetic layer 1. Further, the magnetoresistive element 10 may have a cap layer on the surface of the first ferromagnetic layer 1 opposite to the second ferromagnetic layer 2. Examples of the cap layer, seed layer or buffer layer include MgO, W, Mo, Ru, Ta, Cu, Cr and a laminated film thereof. The film thickness of each of these layers may be about 2 to 10 nm.

<First high frequency path>
The first high-frequency path 20 is a high-frequency signal path between the magnetoresistive sensor 10 and the first port 31. The first high-frequency path 20 shown in FIG. 1 is a high-frequency line located between the magnetoresistive sensor 10 and the first port 31 and connecting the magnetoresistive element 10 and the first port 31. The first high frequency path 20 shown in FIG. 1 electrically connects the magnetoresistive sensor 10 and the first port 31.

The first high-frequency path 20 has a high-frequency magnetic field application unit 21 in the middle. The high-frequency magnetic field application unit 21 is electrically connected to the magnetoresistive element 10 and the first port 31 between the magnetoresistive element 10 and the first port 31. The high-frequency magnetic field application unit 21 is located in the vicinity of the magnetoresistive sensor 10. The high-frequency magnetic field application unit 21 is arranged apart from the magnetoresistive sensor 10 in the stacking direction. For example, an insulator is provided between the high-frequency magnetic field application unit 21 and the magnetoresistive sensor 10. The high-frequency magnetic field application unit 21 is located at a position overlapping the magnetoresistive element 10 when viewed from the stacking direction of the magnetoresistive element 10, for example.

For example, a high-frequency signal generated by noise or a high-frequency signal output from the magnetoresistive element 10 in response to a change in the resistance value of the magnetoresistive element 10 is transmitted along the first high-frequency path 20. A high-frequency current flows inside the high-frequency magnetic field application unit 21. The high-frequency magnetic field application unit 21 is arranged at a position where a high-frequency magnetic field generated by a high-frequency current flowing inside can be applied to the first ferromagnetic layer 1. The high-frequency magnetic field is generated due to the high-frequency current flowing inside the high-frequency magnetic field application unit 21. The high-frequency magnetic field generated by the high-frequency magnetic field application unit 21 is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetization of the first ferromagnetic layer 1 vibrates significantly when the frequency of the high-frequency magnetic field applied to the first ferromagnetic layer 1 is close to the ferromagnetic resonance frequency of the first ferromagnetic layer 1. This phenomenon is a ferromagnetic resonance phenomenon.

<DC application terminal>
The DC application terminal 30 is connected to the power supply 92 and applies a DC current or a DC voltage in the stacking direction of the magnetoresistive element 10. In the present specification, the direct current is a current whose direction does not change with time, and includes a current whose magnitude changes with time. Further, the DC voltage is a voltage whose polarity does not change with time, and includes a voltage whose magnitude changes with time. The power supply 92 may be a DC current source or a DC voltage source. The power supply 92 may be a DC current source capable of generating a constant DC current or a DC voltage source capable of generating a constant DC voltage. Further, the power supply 92 may be a DC current source in which the magnitude of the generated DC current value can be changed, or may be a DC voltage source in which the magnitude of the generated DC voltage value can be changed. The current density of the current applied to the magnetoresistive sensor 10 is preferably smaller than the oscillation threshold current density of the magnetoresistive element 10. The oscillation threshold current density of the magnetic resistance effect element 10 is that when a current having a current density equal to or higher than this value is applied, the magnetization of the first ferromagnetic layer 1 of the magnetic resistance effect element 10 has a constant frequency and a constant amplitude. It is the current density of the threshold value at which the magnetic resistance effect element 10 oscillates when the aging movement is started (the output (resistance value) of the magnetic resistance effect element 10 fluctuates at a constant frequency and a constant amplitude).

<Port 1>
The first port 31 is connected to the first high frequency path 20. The first port 31 is connected to, for example, the end of a high frequency line forming the first high frequency path 20. The first port 31 outputs a high-frequency signal output from the magnetoresistive element 10 to the outside according to a change in the resistance value of the magnetoresistive element 10. The first port 31 is an output terminal of the magnetoresistive device 100.

<Other configurations>
(Reference potential terminal)
The reference potential terminal 32 is connected to the reference potential and determines the reference potential of the magnetoresistive device 100. The reference potential in FIG. 1 is ground GND. The ground GND may be provided outside the magnetoresistive device 100. The reference potential may be other than ground GND.

(line)
The magnetoresistive sensor 10 and each terminal are connected by a line. The shape of the line may be defined as a microstrip line (MSL) type or a coplanar waveguide (CPW) type. When designing a microstrip line (MSL) type or coplanar waveguide (CPW) type, design the line width and the distance between the line and the ground so that the characteristic impedance of the line and the impedance of the circuit system are equal. You may. By designing in this way, the transmission loss of the line can be suppressed.

The line 16 electrically connects the reference potential terminal 32 and the magnetoresistive sensor 10. The first end of the line 16 shown in FIG. 1 is connected to the upper electrode 12, and the second end is connected to the reference potential terminal 32. The direct current input to the direct current application terminal 30 flows through the magnetoresistive element 10 and the line 16.

(Frequency setting section)
The frequency setting unit 90 applies an external magnetic field, which is a static magnetic field, to the magnetoresistive sensor 10. The frequency setting unit 90 is provided in the vicinity of the magnetoresistive sensor 10. The ferromagnetic resonance frequency of the first ferromagnetic layer 1 changes depending on the external magnetic field. The ferromagnetic resonance frequency is, for example, 1 to 100 GHz. The frequency setting unit 90 sets the ferromagnetic resonance frequency of the first ferromagnetic layer 1 of the magnetoresistive sensor 10. The frequency of the signal output by the magnetoresistive device 100 varies depending on the ferromagnetic resonance frequency of the first ferromagnetic layer 1. That is, the frequency setting unit 90 can set the frequency of the output signal of the magnetoresistive device 100. FIG. 1 shows an example in which the frequency setting unit 90 applies an external magnetic field in a direction parallel to the film surface direction of the magnetoresistive element 10 to the magnetoresistive element 10, but the film surface of the magnetoresistive element 10 An external magnetic field having a component in the direction perpendicular to the direction may be applied to the magnetoresistive sensor 10. In this case, the component in the direction perpendicular to the film surface direction of the magnetic resistance effect element 10 may be the direction from the second ferromagnetic layer 2 to the first ferromagnetic layer 1 (upward in FIG. 1) or the first strength. The direction from the magnetic layer 1 to the second ferromagnetic layer 2 (downward in FIG. 1) may be used.

The frequency setting unit 90 is, for example, an electromagnet type or stripline type magnetic field application unit capable of variably controlling the applied magnetic field strength by either voltage or current. Further, the frequency setting unit 90 may be a combination of, for example, an electromagnet type or stripline type magnetic field application unit capable of variably controlling the applied magnetic field strength and a permanent magnet that supplies only a constant magnetic field.

Further, the frequency setting unit 90 may be an electric field application unit that applies an electric field. When the electric field applied to the first ferromagnetic layer 1 of the magnetic resistance effect element 10 is changed by the electric field application portion, the anisotropic magnetic field in the first ferromagnetic layer 1 changes, which is effective in the first ferromagnetic layer 1. The magnetic field changes. Then, the ferromagnetic resonance frequency of the first ferromagnetic layer 1 is set.

Further, the frequency setting unit 90 may be a combination of a piezoelectric body and an electric field application unit. A piezoelectric body is provided in the vicinity of the first ferromagnetic layer of the magnetoresistive element 10, and an electric field is applied to the piezoelectric body. The piezoelectric body to which the electric field is applied is deformed and distorts the first ferromagnetic layer 1. When the first ferromagnetic layer 1 is distorted, the anisotropic magnetic field in the first ferromagnetic layer 1 changes, and the effective magnetic field in the first ferromagnetic layer 1 changes. Then, the ferromagnetic resonance frequency of the first ferromagnetic layer 1 is set.

Further, the frequency setting unit 90 includes a control film having an electromagnetic effect which is an anti-ferromagnetic material or a ferri magnetic material, a magnetic field application unit which applies a magnetic field to the control film, and an electric field application unit which applies an electric field to the control film. You may. An electric field and a magnetic field are applied to a control film provided so as to magnetically bond with the first ferromagnetic layer 1. When at least one of the electric field and the magnetic field applied to the control film is changed, the exchange-coupled magnetic field in the first ferromagnetic layer 1 changes, and the effective magnetic field in the first ferromagnetic layer 1 changes. Then, the ferromagnetic resonance frequency of the first ferromagnetic layer 1 is set.

Further, when the ferromagnetic resonance frequency of the first ferromagnetic layer 1 of the magnetoresistive element 10 is a desired frequency, the frequency setting unit 90 may not be provided.

(Power supply)
The power supply 92 may be provided outside the magnetoresistive device 100. The power supply 92 applies a direct current in the stacking direction of the magnetoresistive element 10. As the power supply 92, a known one can be used.

(Inductor, capacitor)
The inductor 91 cuts the high frequency component of the current and allows the invariant component of the current to pass through. The capacitor 93 passes a high frequency component of the current and cuts an invariant component of the current. The inductor 91 is arranged in a portion where the flow of high-frequency current is desired to be suppressed, and the capacitor 93 is arranged in a portion where the flow of DC current is desired to be suppressed.

The inductor 91 in FIG. 1 is provided between the DC application terminal 30 and the first high frequency path 20. The inductor 91 suppresses the high-frequency current output from the magnetoresistive element 10 from reaching the power supply 92. As the inductor 91, a chip inductor, an inductor with a pattern line, a resistance element having an inductor component, or the like can be used. The inductance of the inductor 91 may be, for example, 10 nH or more. If the power supply 92 connected to the DC application terminal 30 has a function of cutting a high frequency component of the current and at the same time passing an invariant component of the current, the inductor 91 may be omitted.

The capacitor 93 in FIG. 1 is provided in the first high frequency path 20. The capacitor 93 in FIG. 1 is provided between the connection point between the line leading to the DC application terminal 30 and the high frequency line forming the first high frequency path 20, and the first port 31. The capacitor 93 suppresses the direct current applied from the direct current application terminal 30 from flowing to the first port 31. A known capacitor 93 can be used.

<Operation of magnetoresistive device>
FIG. 2 is a schematic diagram for explaining the operation of the magnetoresistive device 100 according to the first embodiment. First, the first signal R1, which is a high frequency signal, flows through the first high frequency path 20. The high frequency signal is, for example, a signal having a frequency of 100 MHz or more. The high frequency signal flows as a high frequency current in the first high frequency path 20. The first signal R1 is, for example, noise. Noise is generated, for example, when the power supply 92 is turned on. The signal R1 propagates through the high-frequency magnetic field application unit 21 and reaches the first port 31. The signal R1 passing through the high-frequency magnetic field application unit 21 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10.

The magnetization of the first ferromagnetic layer 1 vibrates in response to the high-frequency magnetic field generated by the signal R1 passing through the high-frequency magnetic field application unit 21. When the signal R1 includes a signal having a frequency close to the ferromagnetic resonance frequency of the first ferromagnetic layer 1, the magnetization of the first ferromagnetic layer 1 vibrates greatly at that frequency. The resistance value of the magnetoresistive element 10 changes due to the vibration of the magnetization of the first ferromagnetic layer 1. The power supply 92 applies a direct current to the magnetoresistive element 10. The direct current flows in the stacking direction of the magnetoresistive element 10. The direct current flows through the line 16 to the ground GND. The potential of the magnetoresistive sensor 10 changes according to Ohm's law. The signal R2, which is a high-frequency signal, is generated in response to a change in the potential of the magnetoresistive element 10 (change in resistance value). The signal R2 is output from the magnetoresistive sensor 10 to the first high frequency path 20.

The signal R2 passes through the high-frequency magnetic field application unit 21 of the first high-frequency path 20 and reaches the first port 31. The signal R2 passing through the high-frequency magnetic field application unit 21 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetoresistive sensor 10 receives a high-frequency magnetic field and outputs a signal R3, which is a high-frequency signal, to the first high-frequency path 20. The signal R3 flows through the high-frequency magnetic field application unit 21 of the first high-frequency path 20 and reaches the first port 31. The signal R3 passing through the high-frequency magnetic field application unit 21 generates a high-frequency magnetic field again. The magnetoresistive device 100 repeats this cycle.

The cycle in which the signal passes through the high-frequency magnetic field application unit 21, the high-frequency magnetic field generated by the signal is applied to the first ferromagnetic layer 1, and the magnetoresistive sensor 10 outputs the signal to the first high-frequency path 20 is defined as one cycle. .. Hereinafter, in each cycle, the signal passing through the high frequency magnetic field application unit 21 (for example, signal R1) is referred to as an input signal, and the signal output from the magnetoresistive sensor 10 (for example, signal R2) is referred to as an output signal.

The magnetization of the first ferromagnetic layer 1 of the magnetic resistance effect element 10 vibrates greatly in the vicinity of the ferromagnetic resonance frequency, and does not vibrate much in the vicinity of the ferromagnetic resonance frequency. When the magnetization of the first ferromagnetic layer 1 vibrates significantly, the resistance change of the magnetoresistive element 10 becomes large, and a large signal is output from the magnetoresistive element 10. Therefore, with each cycle, the relative strength of the signal at the frequency near the ferromagnetic resonance frequency increases with respect to the signal at the frequency outside the vicinity of the ferromagnetic resonance frequency in the output signal and the input signal (frequency filtering is performed). NS). As a result, the frequency selectivity of the magnetoresistive device 100 is improved.

Here, the ratio of the input signal to the output signal is referred to as an S21 parameter (hereinafter referred to as S21). S21 is represented by [S21 (dB)] = 10 × log ₁₀ ([output signal strength] / [input signal strength]). Hereinafter, the ratio of the input signal (for example, signal R1) passing through the high-frequency magnetic field application unit 21 and the output signal (for example, signal R2) output from the magnetoresistive sensor 10 in each cycle is set as the first S parameter (high-frequency magnetic field). It is referred to as S21) of the application unit 21 and the magnetoresistive element 10. When the output signal output from the magnetoresistive sensor 10 is larger than the input signal passing through the high-frequency magnetic field application unit 21 in each cycle, the first S parameter becomes positive. On the contrary, when the output signal output from the magnetoresistive sensor 10 is smaller than the input signal passing through the high-frequency magnetic field application unit 21 in each cycle, the first S parameter becomes negative.

When the first S parameter is positive, the input signal passing through the high-frequency magnetic field application unit 21 and the output signal output from the magnetoresistive sensor 10 increase with each cycle. The first S parameter can be adjusted, for example, by adjusting the amount of direct current applied to the magnetoresistive sensor 10 from the direct current application terminal 30. FIG. 3 is a graph showing an example of the relationship between the intensity of the input signal passing through the high-frequency magnetic field application unit 21 and the intensity of the signal output from the magnetoresistive sensor. As shown in FIG. 3, the intensity of the output signal from the magnetoresistive sensor 10 increases to a certain value as the intensity of the input signal increases, but gradually saturates. Along with this, the strength of the input signal passing through the high frequency magnetic field application unit 21 is gradually saturated. When the first S parameter is negative, the input signal and the output signal become smaller and attenuate with each cycle. With each cycle of the magnetoresistive device 100, the relative strength of the signal having a frequency near the ferromagnetic resonance frequency to the signal having another frequency increases in the input signal and the output signal. By adjusting the 1st S parameter to be positive in the vicinity of the ferromagnetic resonance frequency and negative in the frequency outside the ferromagnetic resonance frequency, other frequencies of the signal having a frequency near the ferromagnetic resonance frequency can be adjusted. The relative strength of the signal to the signal increases. The magnetoresistive device 100 can selectively amplify the signal strength of a frequency near the ferromagnetic resonance frequency to the output saturation value of the magnetoresistive element 10 each time the cycle is repeated. When the intensity of the output signal (for example, signal Rn (n is a natural number of 2 or more)) reaches the output saturation value of the magnetoresistive element 10, the magnetoresistive device 100 has a stable intensity at a frequency near the ferromagnetic resonance frequency. Is output from the first port 31. In this way, the magnetoresistive device 100 can function as an oscillator having a large difference in output characteristics between the oscillation band and other bands.

Although the first embodiment has been described in detail with reference to the drawings, the configurations and combinations thereof in the first embodiment are examples, and the configurations are added or omitted within a range not deviating from the gist of the present invention. , Replacements, and other changes are possible.

(First modification)
FIG. 4 is a diagram schematically showing a circuit configuration of the magnetoresistive device according to the first modification. The magnetoresistive device 101 according to the first modification shown in FIG. 4 is different from the magnetoresistive device 100 shown in FIG. 1 in that the amplifier 22 is provided in the first high frequency path 20. In the magnetoresistive device 101 shown in FIG. 4, the same reference numerals are given to the same configurations as the magnetoresistive device 100 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 100 in the magnetoresistive device 101 according to the first modification will be omitted.

The amplifier 22 is located in the first high frequency path 20. The amplifier 22 is located between the magnetoresistive sensor 10 and the high-frequency magnetic field application unit 21. The amplifier 22 is a device, an apparatus, or the like that amplifies a signal. As the amplifier 22, a known amplifier 22 can be used. When the amplifier 22 amplifies the signal, the magnetoresistive device 101 quickly saturates the output and outputs a signal having a stable intensity from the first port 31. Further, even when the first S parameter in the vicinity of the ferromagnetic resonance frequency is negative, the amplifier 22 amplifies the signal, so that the input signal and the output signal in the vicinity of the ferromagnetic resonance frequency can be increased for each cycle.

Further, the magnetoresistive device 101 can improve the frequency selectivity by having the amplifier 22. When the intensity of the input signal increases in the vicinity of the ferromagnetic resonance frequency and the intensity of the output signal from the magnetoresistive sensor 10 reaches the output saturation value of the magnetoresistive sensor 10, the first S parameter in the vicinity of the ferromagnetic resonance frequency becomes small. Therefore, the frequency selectivity becomes low. The output saturation value of the magnetoresistive sensor 10 and the amplifier 22 so that the signal output from the amplifier 22 reaches the output saturation value earlier than the output signal output from the magnetoresistive sensor 10 in the vicinity of the ferromagnetic resonance frequency. When the output saturation value and the first S parameter are set, the intensity of the output signal from the magnetoresistive sensor 10 does not reach the output saturation value of the magnetoresistive sensor 10, so that the frequency selectivity of the magnetoresistive device 100 is improved. do. For example, when the first S parameter is negative, the output saturation value of the amplifier 22 is made smaller than the output saturation value of the magnetoresistive sensor 10. The relationship between the output saturation value of the magnetoresistive sensor 10 and the output saturation value of the amplifier 22 can be freely adjusted by selecting, for example, the amplifier 22.

"Second embodiment"
FIG. 5 is a diagram showing a circuit configuration of the magnetoresistive device according to the second embodiment. The magnetoresistive device 110 according to the second embodiment has a branch portion 23, and further has a second high frequency path 50 branched from the first high frequency path 20 at the branch portion 23. Different from 100. In FIG. 5, the same components as those of the magnetoresistive device 100 according to the first embodiment are designated by the same reference numerals. Further, the description of the configuration common to the magnetoresistive device 100 according to the first embodiment will be omitted.

The first high-frequency path 20 in FIG. 5 is a high-frequency line between the magnetoresistive sensor 10 and the first port 31. The first high-frequency path 20 in FIG. 5 is a path through which high-frequency signals are transmitted in the order of the magnetoresistive sensor 10, the line 24, the branch portion 23, the line 25, and the first port 31. The line 24 is a line connecting the magnetoresistive element 10 and the branch portion 23. The line 25 is a line connecting the branch portion 23 and the first port 31. The high-frequency signal output from the magnetoresistive sensor 10 is transmitted in the order of the line 24, the branch portion 23, and the line 25, and is output from the first port 31.

The branching portion 23 is a portion that branches the signal from the line 24 into the line 25 and the second high frequency path 50. The branch portion 23 has a first terminal 23a, a second terminal 23b, a third terminal 23c, and a fourth terminal 23d. The first terminal 23a is connected to the line 24 and is electrically connected to the magnetoresistive sensor 10. The second terminal 23b is connected to the line 25 and is electrically connected to the first port 31. The magnetoresistive sensor 10 and the first port 31 are electrically connected via a branch portion 23. The third terminal 23c is connected to the second high frequency path 50. The fourth terminal 23d is connected to the line 17. The line 17 is connected to the reference potential terminal 32C which is connected to the reference potential. The main wire portion 23e between the first terminal 23a and the second terminal 23b and the sub wire portion 23f between the third terminal 23c and the fourth terminal 23d are electromagnetically coupled (line-coupled). ). The secondary wire portion 23f has a resistor 94.

The branch portion 23 shown in FIG. 5 is a directional coupler. When a signal is input from the first terminal 23a of the branch portion 23, a part of the signal is output from the second terminal 23b via the main line portion 23e, and a part of the signal is output from the third terminal 23c via the sub line portion 23f. Therefore, the signal input from the first terminal 23a is separated toward the second terminal 23b and the third terminal 23c. The rate at which the input signal is separated is arbitrary. On the other hand, when a signal is input from the second terminal 23b of the branch portion 23, most of the signal is output from the first terminal 23a via the main line portion 23e without being attenuated. This is because the sub-wire portion 23f has a resistor 94, and it is difficult for the signal to branch toward the fourth terminal 23d. The directional coupler has different functions depending on the direction of the signal input to the branch portion 23.

The second high frequency path 50 is a path through which a high frequency signal branched from the first high frequency path 20 is transmitted. The second high-frequency path 50 is, for example, a high-frequency signal path between the branch portion 23 and the reference potential terminal 32B connected to the reference potential. The reference potential terminal 32B may be replaced with an output terminal. The second high frequency path 50 has a high frequency magnetic field application unit 51. The high-frequency magnetic field application unit 51 is electrically connected to the third terminal 23c. The magnetoresistive sensor 10 and the high-frequency magnetic field application unit 51 are electrically connected via a branch unit 23. The high-frequency magnetic field application unit 51 is the same as the high-frequency magnetic field application unit 21 in the first embodiment. A high-frequency current flows inside the high-frequency magnetic field application unit 51. The high-frequency magnetic field application unit 51 is arranged at a position where a high-frequency magnetic field generated by a high-frequency current flowing inside can be applied to the first ferromagnetic layer 1.

<Operation of magnetoresistive device>
FIG. 6 is a schematic diagram for explaining the operation of the magnetoresistive effect device 110 according to the second embodiment. First, the signal R1, which is the first high-frequency signal, flows through the second high-frequency path 50. The high frequency signal flows as a high frequency current in the second high frequency path 50. The first signal R1 is, for example, noise. Noise is generated, for example, when the power supply 92 is turned on. The signal R1 passes through the high-frequency magnetic field application unit 51, passes through the reference potential terminal 32B, and reaches the ground GND. The signal R1 passing through the high-frequency magnetic field application unit 51 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10.

The magnetization of the first ferromagnetic layer 1 vibrates in response to the high frequency magnetic field generated by the signal R1 (input signal) passing through the high frequency magnetic field application unit 51. When the signal R1 includes a signal having a frequency close to the ferromagnetic resonance frequency, the magnetization of the first ferromagnetic layer 1 vibrates significantly at that frequency. The resistance value of the magnetoresistive element 10 changes due to the vibration of the magnetization of the first ferromagnetic layer 1. The power supply 92 applies a direct current to the magnetoresistive element 10. The direct current flows in the stacking direction of the magnetoresistive element 10. The direct current flows through the line 16 to the ground GND. The potential of the magnetoresistive sensor 10 changes according to Ohm's law. The signal R2, which is a high-frequency signal, is generated in response to a change in the potential of the magnetoresistive element 10 (change in resistance value). The signal R2 (output signal) is output from the magnetoresistive sensor 10 to the first high frequency path 20 (line 24).

The signal R2 passes through the line 24 of the first high frequency path 20 and reaches the branch portion 23. A part of the signal R2 input from the first terminal 23a is output from the second terminal 23b and the third terminal 23c. The signal output from the second terminal 23b is referred to as a signal R2b, and the signal output from the third terminal 23c is referred to as a signal R2a. The signal R2b reaches the first port 31. The signal R2a passes through the high-frequency magnetic field application unit 51, passes through the reference potential terminal 32B, and reaches the ground GND.

The signal R2a (input signal) passing through the high frequency magnetic field application unit 51 generates a high frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetoresistive sensor 10 receives a high-frequency magnetic field and outputs a signal R3 (output signal) to the first high-frequency path 20 (line 24). The magnetoresistive device 110 repeats this cycle.

The magnetization of the first ferromagnetic layer 1 of the magnetic resistance effect element 10 vibrates greatly in the vicinity of the ferromagnetic resonance frequency, and does not vibrate much in the vicinity of the ferromagnetic resonance frequency. Therefore, with each cycle, the relative strength of the signal at the frequency near the ferromagnetic resonance frequency increases with respect to the signal at the frequency outside the vicinity of the ferromagnetic resonance frequency in the output signal and the input signal (frequency filtering is performed). NS). As a result, the frequency selectivity of the magnetoresistive device 110 is improved.

When the first S parameter (high frequency magnetic field application unit 51 and S21 of the magnetoresistive sensor 10) is set positively, the strength of the input signals (R2a, R3a, ..., Rn-1a, Rna) passing through the high frequency magnetic field application unit 51 is increased. It gradually becomes stronger with each cycle (n is a natural number of 2 or more). As a result, the intensity of the output signals (R2, R3, ..., Rn) output from the magnetoresistive sensor 10 gradually increases until the output saturation value of the magnetoresistive element 10 is reached. As a result, the strength of the signals (R2b, R3b, ..., Rnb) output from the second terminal 23b gradually increases until the output of the magnetoresistive sensor 10 is saturated. Therefore, similarly to the magnetoresistive device 100 of the first embodiment, the magnetoresistive device 110 selectively adjusts the signal intensity of the frequency near the ferromagnetic resonance frequency of the magnetoresistive element 10 each time the cycle is repeated. It can be amplified until the output is saturated. When the output of the magnetoresistive element 10 is saturated, the magnetoresistive device 110 outputs a signal having a stable intensity (for example, a signal Rnb) from the first port 31. Similar to the magnetoresistive device 100 of the first embodiment, the magnetoresistive device 110 functions as an oscillator.

Although the second embodiment has been described in detail with reference to the drawings, the configurations and combinations thereof in the second embodiment are examples, and the configurations are added or omitted within a range not deviating from the gist of the present invention. , Replacements, and other changes are possible.

(Second modification)
FIG. 7 is a diagram schematically showing a circuit configuration of the magnetoresistive device according to the second modification. The magnetoresistive device 111 according to the second modification shown in FIG. 7 is different from the magnetoresistive device 110 shown in FIG. 5 in that the amplifier 22 is provided in the first high frequency path 20. In the magnetoresistive device 111 shown in FIG. 7, the same reference numerals are given to the same configurations as the magnetoresistive device 110 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 110 in the magnetoresistive device 111 according to the second modification will be omitted.

The amplifier 22 shown in FIG. 7 is located on the line 24 (between the magnetoresistive sensor 10 and the branch portion 23 in the first high frequency path 20). The amplifier 22 may be located between the branch portion 23 of the second high frequency path 50 and the high frequency magnetic field application portion 51. The amplifier 22 may be located both on the line 24 and between the branch portion 23 of the second high frequency path 50 and the high frequency magnetic field application portion 51. The amplifier 22 is similar to the amplifier 22 shown in FIG. When the amplifier 22 amplifies the signal, the magnetoresistive device 111 reaches the output saturation value quickly and outputs a signal having a stable intensity from the first port 31. Further, even when the first S parameter in the vicinity of the ferromagnetic resonance frequency is negative, the amplifier 22 amplifies the signal, so that the input signal (signals R2a, R3a, ..., Rna) and the output signal (signal R2a, R3a, ..., Rna) in the vicinity of the ferromagnetic resonance frequency are amplified. R2, R3, ..., Rn and signals R2b, R3b, ..., Rnb) can be increased for each cycle (n is a natural number of 2 or more).

Further, the magnetoresistive device 111 can improve the frequency selectivity by having the amplifier 22. When the intensity of the input signal increases in the vicinity of the ferromagnetic resonance frequency and the intensity of the output signal from the magnetoresistive sensor 10 reaches the output saturation value of the magnetoresistive sensor 10, the first S parameter in the vicinity of the ferromagnetic resonance frequency becomes small. Therefore, the frequency selectivity becomes low. Therefore, the output saturation value of the amplifier 22, the first S parameter, and the signal of the branch portion 23 so that the signal output from the amplifier 22 reaches the output saturation value before the output signal output from the magnetoresistive sensor 10. When the distribution rate (ratio of signal R2a and signal R2b) is set, the strength of the output signal from the magnetoresistive sensor 10 does not reach the output saturation value of the magnetoresistive sensor 10, so that the frequency of the magnetoresistive sensor 111 is selected. Sex improves.

For example, the output saturation value of the amplifier 22 is -10 dBm, the output saturation value of the magnetoresistive sensor 10 is -20 dBm, the first S parameter at the ferromagnetic resonance frequency of the first ferromagnetic layer 1 is + 6 dB, and the amplification factor of the amplifier 22 is + 20 dB. The signal distribution rate of the branch portion 23 to the third terminal 23c is set to −20 dB. A case where the operation of the magnetoresistive device 110 is performed under this condition will be described as an example.

First, the signal R1, which is the first high-frequency signal, flows through the second high-frequency path 50. The signal strength (power) of the signal of the ferromagnetic resonance frequency of the first ferromagnetic layer 1 in the signal R1 is set to, for example, −80 dBm. Hereinafter, the strength of each signal is the strength of the signal having the ferromagnetic resonance frequency of the first ferromagnetic layer 1 in each signal. The high frequency signal flows as a high frequency current in the second high frequency path 50. The first signal R1 is, for example, noise. Noise is generated, for example, when the power supply 92 is turned on. The signal R1 passes through the high-frequency magnetic field application unit 51, passes through the reference potential terminal 32B, and reaches the ground GND. The signal R1 passing through the high-frequency magnetic field application unit 51 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10.

The magnetization of the first ferromagnetic layer 1 vibrates in response to the high frequency magnetic field generated by the signal R1 (input signal) passing through the high frequency magnetic field application unit 51. When the signal R1 includes a signal having a frequency close to the ferromagnetic resonance frequency, the magnetization of the first ferromagnetic layer 1 vibrates significantly at that frequency. The resistance value of the magnetoresistive element 10 changes due to the vibration of the magnetization of the first ferromagnetic layer 1. The power supply 92 applies a direct current to the magnetoresistive element 10. The direct current flows in the stacking direction of the magnetoresistive element 10. The direct current flows through the line 16 to the ground GND. The potential of the magnetoresistive sensor 10 changes according to Ohm's law. The signal R2, which is a high-frequency signal, is generated in response to a change in the potential of the magnetoresistive element 10 (change in resistance value). The first S parameter is + 6 dB, and the intensity of the signal R2 is −74 dBm. The signal R2 (output signal) is output from the magnetoresistive sensor 10 to the first high frequency path 20 (line 24).

The signal R2 passes through the line 24 of the first high frequency path 20 and reaches the amplifier 22. The signal R2 is amplified by the amplifier 22 and has a signal strength of −54 dBm. The amplified signal reaches the branch portion 23. A part of the signal R2 input from the first terminal 23a is output from the second terminal 23b and the third terminal 23c. The signal R2b output from the second terminal 23b reaches the first port 31. The signal strength of the signal R2a output from the third terminal 23c is −74 dBm. The signal R2a passes through the high-frequency magnetic field application unit 51, passes through the reference potential terminal 32B, and reaches the ground GND.

The signal R2a (input signal) passing through the high frequency magnetic field application unit 51 generates a high frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetoresistive sensor 10 receives a high-frequency magnetic field and outputs a signal R3 (output signal) to the first high-frequency path 20 (line 24). The signal strength of the signal R3 is −68 dBm.

The signal R3 passes through the line 24 of the first high frequency path 20 and reaches the amplifier 22. The signal R3 is amplified by the amplifier 22 and has a signal strength of −48 dBm. The amplified signal reaches the branch portion 23. The signal strength of the signal R3a output from the third terminal 23c is −68 dBm.

The magnetoresistive device 111 repeats this cycle. The output saturation value of the amplifier 22 is −10 dBm. When the cycle is repeated, the signal output from the amplifier 22 saturates at -10 dBm. The signal output from the amplifier 22 is distributed by the branch portion 23. The signal distribution rate of the branch portion 23 to the third terminal 23c is -20 dB, and the signal strength of the signal Rn-1a (n is a natural number of 2 or more) output from the third terminal 23c is saturated at -30 dBm (). Saturates when n ≧ 11). The signal Rn-1a passing through the high-frequency magnetic field application unit 51 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The first S parameter is + 6 dB, and the intensity of the signal Rn output from the magnetoresistive sensor 10 is −24 dB m at the maximum. The output saturation value of the magnetoresistive element 10 is -20 dBm, and the intensity of the signal Rn output from the magnetoresistive element 10 (up to -24 dBm) does not reach the output saturation value of the magnetoresistive element 10. The frequency selectivity of the magnetoresistive device 111 is improved.

(Third modification example)
FIG. 8 is a diagram schematically showing a circuit configuration of the magnetoresistive effect device according to the third modification. The magnetoresistive device 112 according to the third modification shown in FIG. 8 is different from the magnetoresistive device 110 shown in FIG. 5 in that an attenuator 52 is provided in the second high frequency path 50. In the magnetoresistive device 112 shown in FIG. 8, the same reference numerals are given to the same configurations as the magnetoresistive device 110 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 110 in the magnetoresistive device 112 according to the third modification will be omitted.

The attenuator 52 shown in FIG. 8 is located between the branch portion 23 of the second high frequency path 50 and the high frequency magnetic field application portion 51. The attenuator 52 may be located on the line 24 (between the magnetoresistive sensor 10 and the branch 23 in the first high frequency path 20). The attenuator 52 is a device, an apparatus, or the like that attenuates a signal. As the attenuator 52, a known one can be used. The attenuator 52 attenuates the signal reaching the high frequency magnetic field application unit 51.

(Fourth modification)
FIG. 9 is a diagram schematically showing a circuit configuration of the magnetoresistive device according to the fourth modification. The magnetoresistive device 113 according to the fourth modification shown in FIG. 9 is different from the magnetoresistive device 111 shown in FIG. 7 in that an attenuator 52 is provided in the second high frequency path 50. In the magnetoresistive device 113 shown in FIG. 9, the same reference numerals are given to the same configurations as those of the magnetoresistive device 111 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 111 in the magnetoresistive device 113 according to the fourth modification will be omitted.

The attenuator 52 shown in FIG. 9 is located between the branch portion 23 of the second high frequency path 50 and the high frequency magnetic field application portion 51. The attenuator 52 is the same as the attenuator in the second modification.

The attenuator 52 attenuates the signal reaching the high frequency magnetic field application unit 51. The signal (input signal) passing through the high-frequency magnetic field application unit 51 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetoresistive sensor 10 receives a high-frequency magnetic field and outputs a signal (output signal) to the first high-frequency path 20 (line 24). Since the magnetoresistive device 113 has the attenuator 52, it becomes easy to set the strength of the output signal from the magnetoresistive element 10 so as not to reach the output saturation value of the magnetoresistive element 10, and it is easy. The frequency selectivity of the magnetoresistive device 113 can be improved.

(Fifth modification)
FIG. 10 is a diagram schematically showing a circuit configuration of the magnetoresistive effect device according to the fifth modification. In the magnetoresistive device 114 according to the fifth modification shown in FIG. 10, the connection state of the branch portion 23 is different from that of the magnetoresistive device 110 shown in FIG. In the magnetoresistive device 114 shown in FIG. 10, the same reference numerals are given to the same configurations as those of the magnetoresistive device 110 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 110 in the magnetoresistive device 114 according to the fifth modification will be omitted.

The branch portion 23 shown in FIG. 10 is a directional coupler. The first terminal 23a is connected to the line 24. The second terminal 23b is connected to the second high frequency path 50. The third terminal 23c is connected to the line 25. The fourth terminal 23d is connected to the line 17. The main line portion 23e connects the line 24 and the second high frequency path 50. The sub line portion 23f connects the line 25 and the line 17.

The magnetoresistive device 114 according to the fifth modification has the same effect as the magnetoresistive device 110, except that the connection state of the branch portion 23 is different from that of the magnetoresistive device 110 shown in FIG.

(6th modification)
FIG. 11 is a diagram schematically showing a circuit configuration of the magnetoresistive effect device according to the sixth modification. The magnetoresistive device 115 according to the sixth modification shown in FIG. 11 differs from the magnetoresistive device 110 shown in FIG. 5 in the configuration of the branch portion 26. In the magnetoresistive device 115 shown in FIG. 11, the same reference numerals are given to the same configurations as those of the magnetoresistive device 110 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 110 in the magnetoresistive device 115 according to the sixth modification will be omitted.

The branch portion 26 is a branch circuit. The branch portion 26 has a first terminal 26a, a second terminal 26b, and a third terminal 26c. The first terminal 26a is connected to the line 24. The second terminal 26b is connected to the line 25. The third terminal 26c is connected to the second high frequency path 50. The branch portion 26 has an impedance element 95. The impedance element 95 may be a resistor, a capacitor, or an inductor. The signal input from the first terminal 26a is branched into the second terminal 26b and the third terminal 26c. The signal input from the first terminal 26a mainly passes to the second terminal 26b side having no impedance element 95, and a part of the signal is branched to the third terminal 26c side having the impedance element 95.

The magnetoresistive device 115 according to the sixth modification is different from the magnetoresistive device 110 shown in FIG. 5 in that the branch portion 26 is a branch circuit, and has the same effect as the magnetoresistive device 110. ..

Further, FIG. 12 is a diagram schematically showing a circuit configuration of another example of the magnetoresistive effect device according to the sixth modification. In the magnetoresistive device 116, the internal configuration of the branch portion 26 is different from the example shown in FIG. The signal input from the first terminal 26a mainly passes to the third terminal 26c side which does not have the impedance element 95, and a part of the signal is branched to the second terminal 26b side which has the impedance element 95.

(7th modification)
FIG. 13 is a diagram schematically showing a circuit configuration of the magnetoresistive effect device according to the seventh modification. The magnetoresistive device 117 according to the seventh modification shown in FIG. 13 differs from the magnetoresistive device 110 shown in FIG. 5 in the configuration of the branch portion 27. In the magnetoresistive device 117 shown in FIG. 13, the same reference numerals are given to the same configurations as the magnetoresistive device 110 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 110 in the magnetoresistive device 117 according to the seventh modification will be omitted.

The branch portion 27 is a distributor. The branch portion 27 has a first terminal 27a, a second terminal 27b, and a third terminal 27c. The first terminal 27a is connected to the line 24. The second terminal 27b is connected to the line 25. The third terminal 27c is connected to the second high frequency path 50. The branch portion 27 has a resistor 94 inside. The signal input from the first terminal 27a is branched into the second terminal 27b and the third terminal 27c. The distribution ratio of the signal input from the first terminal 27a to the second terminal 27b and the third terminal 27c can be freely designed by the resistance value of the resistor 94.

The magnetoresistive device 117 according to the seventh modification is different from the magnetoresistive device 110 shown in FIG. 5 in that the branch portion 27 is a distributor, and has the same effect as the magnetoresistive device 110. ..

Each of the examples of the branching portion shown in the fifth modification to the seventh modification can also be applied as a branching portion in the second modification to the fourth modification.

"Third embodiment"
FIG. 14 is a diagram showing a circuit configuration of the magnetoresistive device according to the third embodiment. In the magnetoresistive device 130 according to the third embodiment, the first high frequency path 20 has an element unit 80 between the magnetoresistive element 10 and the high frequency magnetic field application unit 21, and is connected to the element unit 80. The magnetic resistance shown in FIG. 1 further includes reference potential terminals 32D and 32E connected to the lines 19A, 19B, 19C, lines 19A and 19C, and a second DC application terminal 34 connected to the line 19B. It is different from the effect device 100. In FIG. 14, the same components as those of the magnetoresistive device 100 according to the first embodiment are designated by the same reference numerals. Further, the description of the configuration common to the magnetoresistive device 100 according to the first embodiment will be omitted.

The first high-frequency path 20 is a high-frequency signal path between the magnetoresistive sensor 10 and the first port 31. The first high frequency path 20 shown in FIG. 14 has a line 28, an element unit 80, and a line 29. The line 28 is a line between the magnetoresistive sensor 10 and the element unit 80. The line 29 is a line between the element unit 80 and the first port 31. The high-frequency signal output from the magnetoresistive sensor 10 is input to the element unit 80 via the line 28, and is output from the element unit 80 to the line 29.

The element unit 80 includes a second high-frequency magnetic field application unit 81 and a second magnetoresistive effect element 82. The element unit 80 may have a frequency setting unit 90 in the vicinity of the second magnetoresistive sensor 82 in order to set the ferromagnetic resonance frequency of the third ferromagnetic layer 4 of the second magnetoresistive element 82. .. The ferromagnetic resonance frequency of the third ferromagnetic layer 4 of the second magnetic resistance effect element 82 substantially coincides with, for example, the ferromagnetic resonance frequency of the first ferromagnetic layer 1 of the magnetic resistance effect element 10. In the first high-frequency path 20, the second magnetoresistive sensor 82 is located between the second high-frequency magnetic field application unit 81 and the high-frequency magnetic field application unit 21.

The second magnetoresistive element 82 has a third ferromagnetic layer 4, a second spacer layer 6, and a fourth ferromagnetic layer 5. The second spacer layer 6 is located between the third ferromagnetic layer 4 and the fourth ferromagnetic layer 5. The third ferromagnetic layer 4 is, for example, a magnetization free layer (first magnetization free layer). The fourth ferromagnetic layer 5 is, for example, a magnetization fixed layer or a magnetization free layer (second magnetization free layer). The third ferromagnetic layer 4, the second spacer layer 6, and the fourth ferromagnetic layer 5 are made of the same materials as the examples given in the first ferromagnetic layer 1, the spacer layer 3, and the second ferromagnetic layer 2, respectively. You can choose the configuration. The second magnetoresistive sensor 82 may have an upper electrode 83 and a lower electrode 84.

The second high-frequency magnetic field application unit 81 is arranged apart from the second magnetoresistive effect element 82, and is arranged at a position where the high-frequency magnetic field generated by the high-frequency current flowing inside can be applied to the third ferromagnetic layer 4.

In the element unit 80, the high frequency signal is input to the second high frequency magnetic field application unit 81 and output from the second magnetoresistive sensor 82. That is, the second high-frequency magnetic field application unit 81 is connected to the line 28, and the second magnetoresistive sensor 82 is connected to the line 29.

Further, the element unit 80 is connected to a plurality of lines 19A, 19B, 19C in addition to the line 28 and the line 29. The line 19A connects the second high-frequency magnetic field application unit 81 and the reference potential terminal 32E. The line 19B connects the second magnetoresistive sensor 82 and the second DC application terminal 34. By connecting the second direct current application terminal 34 to the power supply 92, a direct current or a direct current voltage is applied to the second magnetoresistive element 82. The second DC application terminal 34 is the same as the DC application terminal 30. The line 19C connects the second magnetoresistive element 82 and the reference potential terminal 32D.

<Operation of magnetoresistive device>
Next, the operation of the magnetoresistive device 130 according to the third embodiment will be described. First, the signal R1, which is the first high-frequency signal, flows through the high-frequency magnetic field application unit 21. The high-frequency signal flows as a high-frequency current in the high-frequency magnetic field application unit 21. The first signal R1 is, for example, noise. Noise is generated, for example, when the power supply 92 is turned on. The signal R1 passes through the high-frequency magnetic field application unit 21 and reaches the first port 31. The signal R1 passing through the high-frequency magnetic field application unit 21 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10.

The magnetization of the first ferromagnetic layer 1 vibrates in response to the high-frequency magnetic field generated by the signal R1 (input signal) passing through the high-frequency magnetic field application unit 21. When the signal R1 includes a signal having a frequency close to the ferromagnetic resonance frequency of the first ferromagnetic layer 1, the magnetization of the first ferromagnetic layer 1 vibrates greatly at that frequency. The resistance value of the magnetoresistive element 10 changes due to the vibration of the magnetization of the first ferromagnetic layer 1. The power supply 92 connected to the direct current application terminal 30 applies a direct current to the magnetoresistive element 10. The direct current flows in the stacking direction of the magnetoresistive element 10. The direct current flows through the line 16 to the ground GND. The potential of the magnetoresistive sensor 10 changes according to Ohm's law. The signal R2, which is a high-frequency signal, is generated in response to a change in the potential of the magnetoresistive element 10 (change in resistance value). The signal R2 (output signal) is output from the magnetoresistive sensor 10 to the first high frequency path 20 (line 28).

The signal R2 passes through the line 28 of the first high frequency path 20 and reaches the element unit 80. The signal R2 passes through the second high-frequency magnetic field application unit 81 of the element unit 80 and reaches the reference potential terminal 32E. The signal R2 flows as a high-frequency current in the second high-frequency magnetic field application unit 81. The signal R2 passing through the second high-frequency magnetic field application unit 81 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the third ferromagnetic layer 4 of the second magnetoresistive element 82.

The magnetization of the third ferromagnetic layer 4 vibrates in response to the high frequency magnetic field generated by the signal R2 (input signal) passing through the second high frequency magnetic field application unit 81. When the signal R2 includes a signal having a frequency near the ferromagnetic resonance frequency of the third ferromagnetic layer 4, the magnetization of the third ferromagnetic layer 4 vibrates greatly at that frequency. The resistance value of the second magnetoresistive element 82 changes due to the vibration of the magnetization of the third ferromagnetic layer 4. The power supply 92 connected to the second direct current application terminal 34 applies a direct current to the second magnetoresistive element 82. The direct current flows in the stacking direction of the second magnetoresistive element 82. The direct current flows through the line 19C to the ground GND. The potential of the second magnetoresistive sensor 82 changes according to Ohm's law. The signal R2', which is a high frequency signal, is generated according to the change in the potential (change in the resistance value) of the second magnetoresistive element 82. The signal R2'(output signal) is output from the second magnetoresistive sensor 82 to the line 29.

The signal R2'passes through the high frequency magnetic field application unit 21 and reaches the first port 31. The signal R2'passing through the high frequency magnetic field application unit 21 generates a high frequency magnetic field. The high frequency magnetic field is applied to the first ferromagnetic layer 1 of the magnetoresistive element 10. The magnetoresistive sensor 10 receives a high-frequency magnetic field and outputs a signal R3 (output signal) to the first high-frequency path 20 (line 28). The magnetoresistive device 130 repeats this cycle.

The magnetization of the first ferromagnetic layer 1 of the magnetic resistance effect element 10 vibrates greatly in the vicinity of the ferromagnetic resonance frequency, and does not vibrate much in the vicinity of the ferromagnetic resonance frequency. Further, the magnetization of the third ferromagnetic layer 4 of the second magnetic resistance effect element 82 vibrates greatly in the vicinity of the ferromagnetic resonance frequency, and does not vibrate much in the vicinity of the ferromagnetic resonance frequency. Therefore, in the output signal and the input signal, the relative intensity of the signal of the frequency near the ferromagnetic resonance frequency is increased with respect to the signal of the frequency deviating from the vicinity of the ferromagnetic resonance frequency by performing only one cycle (frequency filtering). Will be done). Further, by repeating this cycle, frequency filtering is performed a plurality of times, and the frequency selectivity of the magnetoresistive device 130 is further improved.

Although the third embodiment has been described in detail with reference to the drawings, the configurations and combinations thereof in the third embodiment are examples, and the configurations are added or omitted within a range that does not deviate from the gist of the present invention. , Replacements, and other changes are possible.

(8th modification)
FIG. 15 is a diagram schematically showing a circuit configuration of the magnetoresistive device according to the eighth modification. The magnetoresistive device 131 according to the eighth modification shown in FIG. 15 shares the DC application terminal between the magnetoresistive element 10 and the second magnetoresistive element 82, which is the magnetoresistive effect shown in FIG. Different from device 130. In the magnetoresistive device 131 shown in FIG. 15, the same reference numerals are given to the same configurations as the magnetoresistive device 130 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 130 in the magnetoresistive device 131 according to the eighth modification will be omitted.

The magnetoresistive device 131 is different from the magnetoresistive device 130 shown in FIG. 14 in that the line 28 and the line 19B are connected and the second DC application terminal 34 and the like are omitted. The direct current applied from the power supply 92 branches at the intersection of the line 28 and the line 19B. One of the branched direct currents passes through the line 28 and flows in the stacking direction of the magnetoresistive element 10, and reaches the ground GND from the reference potential terminal 32. The other of the branched direct currents flows through the line 19B in the stacking direction of the second magnetoresistive element 82, and reaches the ground GND from the reference potential terminal 32D.

The magnetoresistive device 131 according to the eighth modification is different from the magnetoresistive device 130 shown in FIG. 14 in that the magnetoresistive element 10 and the second magnetoresistive element 82 share a DC application terminal. However, it has the same effect as the magnetoresistive device 130.

(9th modification)
FIG. 16 is a diagram schematically showing a circuit configuration of the magnetoresistive device according to the ninth modification. In the magnetoresistive device 132 according to the ninth modification shown in FIG. 16, the magnetic resistance shown in FIG. 14 is such that the second high-frequency magnetic field application unit 81 is arranged in connection with the second magnetoresistive element 82. Different from effect device 130. In the magnetoresistive device 132 shown in FIG. 16, the same reference numerals are given to the same configurations as the magnetoresistive device 130 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 130 in the magnetoresistive device 132 according to the ninth modification will be omitted.

In the magnetoresistive device 132, the second high-frequency magnetic field application unit 81 also serves as the upper electrode 83 of the magnetoresistive element 10. The second high-frequency magnetic field application unit 81 is connected to one end of the second magnetoresistive sensor 82. As a result, the line 19C and the reference potential terminal 32D in the magnetoresistive device 130 shown in FIG. 14 are omitted.

The high-frequency signal output from the magnetoresistive sensor 10 branches to the second magnetoresistive element 82 side and the reference potential terminal 32E side. The high-frequency signal passing through the second high-frequency magnetic field application unit 81 generates a high-frequency magnetic field. The high frequency magnetic field is applied to the third ferromagnetic layer 4 of the second magnetoresistive element 82.

The magnetoresistive device 132 according to the ninth modification is the magnetoresistive device 130 shown in FIG. 14 in that the upper electrode 83 of the second magnetoresistive element 82 and the second high frequency magnetic field application unit 81 are connected. However, it has the same effect as the magnetoresistive device 130.

(10th modification)
FIG. 17 is a diagram schematically showing a circuit configuration of the magnetoresistive effect device according to the tenth modification. In the magnetoresistive device 133 according to the tenth modification shown in FIG. 17, the first high frequency path 20 has a plurality of element units 80, and further includes a plurality of lines 19A, 19B, 19C, etc. attached to the element unit 80. The point is different from the magnetoresistive effect device 130 shown in FIG. In the magnetoresistive device 133 shown in FIG. 17, the same reference numerals are given to the same configurations as the magnetoresistive device 130 shown in FIG. Further, the description of the configuration common to the magnetoresistive device 130 in the magnetoresistive device 133 according to the tenth modification will be omitted.

The first high-frequency path 20 is a high-frequency signal path between the magnetoresistive sensor 10 and the first port 31. The first high frequency path 20 shown in FIG. 17 has a line 28, a plurality of element units 80 (element units 80A, 80B, 80C), lines 28A, 28B, and a line 29. The line 28 is a line between the magnetoresistive sensor 10 and the element unit 80A. The line 29 is a line between the element unit 80C and the first port 31. The lines 28A and 28B are lines between adjacent element portions 80 in the first high frequency path 20. Each element unit 80 has a second high-frequency magnetic field application unit 81 and a second magnetoresistive effect element 82. Each second magnetoresistive sensor 82 is located between the second high-frequency magnetic field application unit 81 and the high-frequency magnetic field application unit 21 belonging to the same element unit 80.

The high-frequency signal is transmitted between the magnetoresistive element 10 and the first port 31 in the order of line 28, element 80A, line 28A, element 80B, line 28B, element 80C, line 29, and high-frequency magnetic field application unit 21. .. The frequency of the high-frequency signal output from the magnetoresistive sensor 10 is filtered each time it passes through each of the element portions 80. As a result, the magnetoresistive device 132 has higher frequency selectivity.

Up to this point, some modifications of the magnetoresistive device according to the third embodiment have been described. Modifications of the magnetoresistive device according to the third embodiment are not limited to these. For example, the characteristic configuration in another embodiment or other modification may be combined with the configuration according to the third embodiment.

(11th modification)
FIG. 18 is a diagram schematically showing a circuit configuration of the magnetoresistive device 134 according to the eleventh modification. The magnetoresistive device 134 shown in FIG. 18 adds an amplifier 22 to the magnetoresistive device 130 shown in FIG. That is, the magnetoresistive device 134 shown in FIG. 18 is a combination of the characteristic configurations of the magnetoresistive device 101 shown in FIG. 4 and the magnetoresistive device 130 shown in FIG. In the magnetoresistive device 134 shown in FIG. 18, the high-frequency signal transmitted through the first high-frequency path 20 includes the magnetoresistive element 10, the line 28, the second high-frequency magnetic field application unit 81, the second magnetoresistive element 82, and the amplifier 22. The line 29, the high-frequency magnetic field application unit 21, and the first port 31 are transmitted in this order. The amplifier 22 is provided between the magnetoresistive sensor 10 and the high-frequency magnetic field application unit 21 in the first high-frequency path 20. In the example shown in FIG. 18, the amplifier 22 is provided on the line 29 between the second magnetoresistive sensor 82 and the high-frequency magnetic field application unit 21. The amplifier 22 may be provided on the line 28 between the magnetoresistive sensor 10 and the second high-frequency magnetic field application unit 81.

In the magnetic resistance effect devices 130 to 132 and 134 shown in FIGS. 14 to 16 and 18, the pair of the magnetic resistance effect element 10 and the high frequency magnetic field application unit 21 is the first element unit (the first element unit is the magnetic resistance effect element 10). And the high-frequency magnetic field application unit 21), the magnetic resistance effect element 10 of the first element unit and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the second element unit (element unit 80). Is electrically connected, and the magnetic resistance effect element (second magnetic resistance effect element 82) of the second element unit (element unit 80) and the high-frequency magnetic field application unit 21 of the first element unit are electrically connected. ing.

Further, in the magnetic resistance effect device 133 shown in FIG. 17, the pair of the magnetic resistance effect element 10 and the high frequency magnetic field application unit 21 is the first element unit (the first element unit is the magnetic resistance effect element 10 and the high frequency magnetic field application unit 21). The magnetic resistance effect element 10 of the first element unit and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the second element unit (element unit 80A) are electrically connected. ing. Further, the magnetoresistive element (second magnetoresistive element 82) of the second element unit (element unit 80A) and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the third element unit (element unit 80B). ) Is electrically connected. Further, the magnetoresistive element (second magnetoresistive element 82) of the third element unit (element unit 80B) and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the fourth element unit (element unit 80C). ) Is electrically connected. Further, the magnetoresistive element (second magnetoresistive element 82) of the fourth element unit (element unit 80C) and the high-frequency magnetic field application unit 21 of the first element unit are electrically connected.

That is, the magnetoresistive effect devices 130 to 134 have N element portions (N is a natural number of 2 or more), and the magnetism of the Mth element portion (M is a natural number satisfying 1 ≦ M ≦ N-1). The resistance effect element and the high frequency magnetic field application part of the M + 1st element part are electrically connected, and the magnetoresistive element of the Nth element part and the high frequency magnetic field application part of the first element part are electrically connected. Can be generally expressed as being. The magnetoresistive effect devices 130 to 132 and 134 shown in FIGS. 14 to 16 and 18 are examples in the case of N = 2. The magnetoresistive device 133 shown in FIG. 17 is an example in the case of N = 4.

(12th modification)
FIG. 19 is a diagram schematically showing a circuit configuration of the magnetoresistive device 135 according to the twelfth modification. The magnetoresistive device 135 shown in FIG. 19 has a branch portion 23 added to the magnetoresistive device 130 shown in FIG. That is, the magnetoresistive device 135 shown in FIG. 19 is a combination of the characteristic configurations of the magnetoresistive device 110 shown in FIG. 5 and the magnetoresistive device 130 shown in FIG. In the magnetoresistive device 135, the first high frequency path 20 has an element portion 80 between the magnetoresistive element 10 and the branch portion 23, and the second magnetoresistive element 82 in the first high frequency path 20 It is located between the second high-frequency magnetic field application section 81 and the branch section 23. In the magnetoresistive device 135 shown in FIG. 19, the high-frequency signal transmitted through the first high-frequency path 20 includes the magnetoresistive element 10, the line 28, the second high-frequency magnetic field application unit 81, the second magnetoresistive element 82, and the line 29. The branch portion 23, the line 25, and the first port 31 are transmitted in this order.

(13th modification)
FIG. 20 is a diagram schematically showing a circuit configuration of the magnetoresistive device 136 according to the thirteenth modification. The magnetoresistive device 136 shown in FIG. 20 is different from the magnetoresistive device 135 shown in FIG. 19 in that the magnetoresistive element 10 and the second magnetoresistive element 82 share a DC application terminal. That is, the magnetoresistive device 136 shown in FIG. 20 is a combination of the characteristic configurations of the magnetoresistive device 135 shown in FIG. 19 and the magnetoresistive device 131 shown in FIG. In the magnetoresistive device 136 shown in FIG. 20, the high-frequency signal transmitted through the first high-frequency path 20 includes the magnetoresistive element 10, the line 28, the second high-frequency magnetic field application unit 81, the second magnetoresistive element 82, and the line 29. The branch portion 23, the line 25, and the first port 31 are transmitted in this order.

(14th modification)
FIG. 21 is a diagram schematically showing a circuit configuration of the magnetoresistive device 137 according to the 14th modification. In the magnetoresistive device 137 shown in FIG. 21, the element unit 80 is not provided in the first high frequency path 20, and the element unit 80 is provided between the branch portion 23 and the high frequency magnetic field application unit 51 in the second high frequency path 50. It differs from the magnetoresistive device 135 shown in FIG. 19 in that it is provided. The magnetoresistive device 137 is a modification of the magnetoresistive device 135. In the magnetoresistive device 137, the second high-frequency path 50 has an element portion 80 between the branch portion 23 and the high-frequency magnetic field application portion 51. In the second high-frequency path 50, the second magnetoresistive sensor 82 is located between the second high-frequency magnetic field application unit 81 and the high-frequency magnetic field application unit 51. In the magnetoresistive device 137 shown in FIG. 21, the high-frequency signal transmitted through the first high-frequency path 20 is transmitted in the order of the magnetoresistive element 10, the line 24, the branch portion 23, the line 25, and the first port 31.

The second high frequency path 50 is a path through which a high frequency signal branched from the first high frequency path 20 is transmitted. The second high frequency path 50 shown in FIG. 21 has a line 53, an element unit 80, and a line 54. The line 54 has a high frequency magnetic field application unit 51. The line 53 is a line between the branch portion 23 and the element portion 80. The line 54 is a line between the element unit 80 and the reference potential terminal 32B. The high frequency signal is input to the element unit 80 via the line 53, and is output from the element unit 80 to the line 54. The second high-frequency magnetic field application unit 81 is connected to the line 53, and the second magnetoresistive sensor 82 is connected to the line 54. The high-frequency signal branched to the second high-frequency path 50 side in the branch portion 23 passes through the second high-frequency magnetic field application unit 81 and flows as a high-frequency current in the second high-frequency magnetic field application unit 81. The high frequency signal (input signal) passing through the second high frequency magnetic field application unit 81 generates a high frequency magnetic field. The high frequency magnetic field is applied to the third ferromagnetic layer 4 of the second magnetoresistive element 82. The second magnetoresistive sensor 82 receives a high-frequency magnetic field and outputs a high-frequency signal (output signal) to the line 54.

In the magnetoresistive device 137, the branch portion 23 and the high-frequency magnetic field are applied in the second high-frequency path 50 in the magnetoresistive device 137, just as the magnetoresistive device 133 shown in FIG. A plurality of element units 80 may be provided between the unit 51 and the unit 51.

(15th modification)
FIG. 22 is a diagram schematically showing a circuit configuration of the magnetoresistive device 138 according to the fifteenth modification. The magnetoresistive device 138 shown in FIG. 22 adds an amplifier 22 to the magnetoresistive device 135 shown in FIG. That is, the magnetoresistive device 138 shown in FIG. 22 is a combination of the characteristic configurations of the magnetoresistive device 135 shown in FIG. 19 and the magnetoresistive device 101 shown in FIG. In the magnetoresistive device 138 shown in FIG. 22, the high-frequency signal transmitted through the first high-frequency path 20 includes the magnetoresistive element 10, the line 28, the element unit 80, the line 29, the amplifier 22, the branch unit 23, the line 25, and the first. It is transmitted in the order of port 31. The amplifier 22 is provided between the magnetoresistive sensor 10 and the branch portion 23 in the first high frequency path 20. In the example shown in FIG. 22, the amplifier 22 is provided on the line 29 between the second magnetoresistive sensor 82 and the branch portion 23. The amplifier 22 may be provided on the line 28 between the magnetoresistive sensor 10 and the second high-frequency magnetic field application unit 81. Further, the amplifier 22 may be provided between the branch portion 23 in the second high frequency path 50 and the high frequency magnetic field application portion 51.

(16th variant)
FIG. 23 is a diagram schematically showing a circuit configuration of the magnetoresistive device 139 according to the 16th modification. In the magnetoresistive device 139 shown in FIG. 23, an attenuator 52 is added to the magnetoresistive device 135 shown in FIG. That is, the magnetoresistive device 139 shown in FIG. 23 is a combination of the characteristic configurations of the magnetoresistive device 135 shown in FIG. 19 and the magnetoresistive device 112 shown in FIG. In the magnetoresistive device 139 shown in FIG. 23, the high-frequency signal transmitted through the first high-frequency path 20 is the magnetoresistive element 10, the line 28, the element 80, the line 29, the branch 23, the line 25, and the first port 31. It is transmitted in order. The attenuator 52 is provided between the branch portion 23 and the high frequency magnetic field application portion 51 in the second high frequency path 50. The attenuator 52 may be provided between the magnetoresistive sensor 10 and the branch portion 23 in the first high frequency path 20.

(17th modification)
FIG. 24 is a diagram schematically showing a circuit configuration of the magnetoresistive device 140 according to the 17th modification. In the magnetoresistive device 140 shown in FIG. 24, a plurality of element units 80 (element units 80A, 80B, 80C) are further added to the first high frequency path 20 of the magnetoresistive device 137 shown in FIG. That is, the magnetoresistive device 140 shown in FIG. 24 combines the characteristic configurations of the magnetoresistive device 133 shown in FIG. 17, the magnetoresistive device 135 shown in FIG. 19, and the magnetoresistive device 137 shown in FIG. It is a thing. In the magnetoresistive device 140 shown in FIG. 24, the high-frequency signal transmitted through the first high-frequency path 20 includes the magnetoresistive element 10, the line 28, the element 80, the line 28A, the element 80, the line 29, the branch 23, and the line. It is transmitted in the order of 25 and the first port 31.

In the magnetic resistance effect devices 135, 136, 138, and 139 shown in FIGS. 19, 20, 22, and 23, the pair of the magnetic resistance effect element 10 and the high frequency magnetic field application unit 51 is the first element unit (the first element unit is magnetic). (Has a resistance effect element 10 and a high-frequency magnetic field application unit 51), the magnetic resistance effect element 10 of the first element unit and the high-frequency magnetic field application unit (second high-frequency magnetic field application) of the second element unit (element unit 80). The unit 81) is electrically connected, and the magnetic resistance effect element (second magnetic resistance effect element 82) of the second element unit (element unit 80) and the high-frequency magnetic field application unit 51 of the first element unit are branched. It is electrically connected via the unit 23.

In the magnetic resistance effect device 137 shown in FIG. 21, the pair of the magnetic resistance effect element 10 and the high frequency magnetic field application unit 51 is the first element unit (the first element unit is the magnetic resistance effect element 10 and the high frequency magnetic field application unit 51). The magnetic resistance effect element 10 of the first element unit and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the second element unit (element unit 80) are electrically connected via the branch portion 23. The magnetic resistance effect element (second magnetic resistance effect element 82) of the second element unit (element unit 80) and the high-frequency magnetic field application unit 51 of the first element unit are electrically connected via the branch portion 23. Is connected.

Further, in the magnetic resistance effect device 140 shown in FIG. 24, the pair of the magnetic resistance effect element 10 and the high frequency magnetic field application unit 51 is the first element unit (the first element unit is the magnetic resistance effect element 10 and the high frequency magnetic field application unit 51). The magnetic resistance effect element 10 of the first element unit and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the second element unit (element unit 80A) are electrically connected. ing. Further, the magnetoresistive element (second magnetoresistive element 82) of the second element unit (element unit 80A) and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the third element unit (element unit 80B). ) Is electrically connected. Further, the magnetoresistive element (second magnetoresistive element 82) of the third element unit (element unit 80B) and the high-frequency magnetic field application unit (second high-frequency magnetic field application unit 81) of the fourth element unit (element unit 80C). ) Is electrically connected via the branch portion 23. Further, the magnetoresistive element (second magnetoresistive element 82) of the fourth element unit (element unit 80C) and the high-frequency magnetic field application unit 51 of the first element unit are electrically connected.

That is, the magnetoresistive device 135-140 has N element portions (N is a natural number of 2 or more), and the magnetism of the Mth element portion (M is a natural number satisfying 1 ≦ M ≦ N-1). The resistance effect element and the high frequency magnetic field application part of the M + 1st element part are electrically connected, and the magnetoresistive element of the Nth element part and the high frequency magnetic field application part of the first element part are electrically connected. Can be generally expressed as being. The magnetoresistive effect devices 135 to 139 shown in FIGS. 19 to 23 are examples in the case of N = 2. The magnetoresistive device 140 shown in FIG. 24 is an example in the case of N = 4.

1 1st ferromagnetic layer 2 2nd ferromagnetic layer 3 Spacer layer 10 Magnetoresist sensor 12,83 Upper electrode 14,84 Lower electrode 16, 17, 19A, 19B, 19C, 24, 25, 28, 28A, 28B, 29, 53, 54 Line 20 1st high frequency path 21, 51 High frequency magnetic field application part 22 Amplifier 23, 26, 27 Branch part 23a, 26a, 27a 1st terminal 23b, 26b, 27b 2nd terminal 23c, 26c, 27c 3rd Terminal 23d 4th terminal 23e Main wire 23f Sub wire 30 DC application terminal 31 1st port 32, 32B, 32C, 32D, 32E Reference potential terminal 34 2nd DC application terminal 50 2nd high frequency path 52 Attenuator 80, 80A, 80B, 80C Element unit 81 Second high-frequency magnetic field application unit 82 Second magnetoresistive effect element 90 Frequency setting unit 91 inductor 92 Power supply 93 Condenser 94 Resistance 95 Impedance element 100, 101, 110, 111, 112, 113, 114, 115, 116, 117, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140 Magneto Resistive Devices

Claims (8)

The first port that outputs high frequency signals and
A magnetoresistive sensor comprising a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer.
A first high-frequency path, which is a high-frequency signal path between the magnetoresistive sensor and the first port,
It is provided with a DC application terminal which is connected to the magnetoresistive sensor and can connect a power source for applying a DC current or a DC voltage to the magnetoresistive element.
The first high-frequency path or the second high-frequency path branched from the first high-frequency path has a high-frequency magnetic field application portion arranged apart from the magnetoresistive sensor.
A magnetoresistive device in which a high-frequency magnetic field generated by a high-frequency current flowing inside the high-frequency magnetic field application portion is applied to the first ferromagnetic layer. The magnetoresistive device according to claim 1, wherein the first high-frequency path has an amplifier between the magnetoresistive element and the high-frequency magnetic field application unit. The first high-frequency path has an element portion between the magnetoresistive sensor and the high-frequency magnetic field application portion.
The element part is
A second magnetoresistive sensor comprising a third ferromagnetic layer, a fourth ferromagnetic layer, and a second spacer layer sandwiched between the third ferromagnetic layer and the fourth ferromagnetic layer.
It has a second high-frequency magnetic field application unit connected to or separated from the second magnetoresistive sensor.
A high-frequency magnetic field generated by a high-frequency current flowing inside the second high-frequency magnetic field application portion is applied to the third ferromagnetic layer.
The second magnetoresistive sensor is connected to the DC application terminal or a second DC application terminal to which a power source for applying a DC current or a DC voltage can be connected to the second magnetic resistance effect element.
The magnetoresistive device according to claim 1 or 2, wherein in the first high-frequency path, the second magnetoresistive element is located between the second high-frequency magnetic field application unit and the high-frequency magnetic field application unit. It has a branch portion where the second high frequency path branches from the first high frequency path.
The magnetoresistive device according to claim 1 or 2, wherein the second high-frequency path has the high-frequency magnetic field application portion. The magnetoresistive device according to claim 4, wherein an amplifier is provided between the magnetoresistive element and the branch portion in the first high frequency path. The magnetoresistive effect device according to claim 4 or 5, wherein an amplifier is provided between the branch portion and the high frequency magnetic field application portion in the second high frequency path. Claims 4 to 6 having an attenuator between the magnetoresistive element and the branch portion in the first high-frequency path, or between the branch portion and the high-frequency magnetic field application portion in the second high-frequency path. The magnetoresistive effect device according to any one of the above. The element portion is provided at least between the magnetoresistive effect element and the branch portion in the first high frequency path and between the branch portion and the high frequency magnetic field application portion in the second high frequency path. ,
The element part is
A second magnetoresistive sensor comprising a third ferromagnetic layer, a fourth ferromagnetic layer, and a second spacer layer sandwiched between the third ferromagnetic layer and the fourth ferromagnetic layer.
It has a second high-frequency magnetic field application unit connected to or separated from the second magnetoresistive sensor.
A high-frequency magnetic field generated by a high-frequency current flowing inside the second high-frequency magnetic field application portion is applied to the third ferromagnetic layer.
The second magnetoresistive sensor is connected to the DC application terminal or a second DC application terminal to which a power source for applying a DC current or a DC voltage can be connected to the second magnetic resistance effect element.
When the first high-frequency path has the element portion, the second magnetoresistive sensor is located between the second high-frequency magnetic field application portion and the branch portion in the first high-frequency path.
4. When the second high-frequency path has the element portion, the second magnetoresistive element is located between the second high-frequency magnetic field application portion and the high-frequency magnetic field application portion in the second high-frequency path. The magnetoresistive effect device according to any one of 7 to 7.

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