JP2003344258A - Vertical magnetic field applying device for magnetic force microscope - Google Patents

Abstract

(57) [Summary] An object of the present invention is to diversify an observation mode by securing a high magnetic field environment and realizing highly accurate setting of the magnetic field environment. A core (21) includes first and second pole pieces (2).
2 and 23 are provided so as to face each other, an insertion hole 231 is provided in one of the first pole pieces 23, and the first pole piece 22 and the second pole piece 23 are inserted through the insertion hole 231.
The magnetic probe 11 and the stage 20 are disposed between the magnetic probe 11 and the stage 20 via a holder member 33 made of a non-magnetic material. , And the core 21 are separated from each other, and the coils 27 and 28 constituting the magnetic circuit are configured to be thermally controlled via the cooling units 30 and 31, thereby achieving the intended purpose.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic force microscope (MFM) used for observing a nanoscale magnetization state of a sample such as a magnetic thin film material, and particularly to observing the magnetization state of the sample in a perpendicular magnetic field. The present invention relates to a vertical magnetic field applying device.

[0002]

2. Description of the Related Art In the field of material development, by observing the magnetic domain structure of a sample such as a semiconductor on a nanoscale,
Development of ultra-high permanent magnet materials and magnetic head materials is underway. For such development, a magnetic force microscope (MFM)
Is used to obtain an image of the magnetic domain structure of the sample.

That is, in the magnetic force microscope, for example, when the magnetic probe portion 11 is brought close to the sample 10 as shown in FIG. 4, the magnetic probe portion 11 is attracted to the sample 10 by the leakage magnetic field from the sample 10. Being repulsed. On this occasion,
The magnetic probe 11 is irradiated with light from the light source 12, and the light reflected by the magnetic probe 11 is detected by the photodetector 13. The photodetector 13 bends the magnetic probe 11. The amount is detected. The magnetic domain structure of the sample 10 is imaged and acquired by an arithmetic processing unit (not shown) based on the bending amount of the magnetic probe unit 11.

By the way, the observation of such a magnetic domain structure is
By observing a magnetic domain in a desired magnetic field environment, it becomes possible to observe a change in the magnetic domain and a differential magnetic image, and further promote resource development. Therefore, when observing the magnetic domain structure, a vertical magnetic field application method that applies a vertical magnetic field to the sample 10 to enable magnetic domain observation is adopted. As a method of applying this vertical magnetic field, a method is known in which a permanent magnet is arranged outside the magnetic force microscope to form a magnetic field, or a magnetic force microscope is arranged in a strong magnetic field to form a magnetic field environment.

However, in the case of the former, the above-mentioned vertical magnetic field applying means has a magnetic field strength of at most 2 to 3 k due to its configuration.
It is about Oe, and the observation form is restricted. Further, in the latter case, it is difficult to apply a stable vertical magnetic field due to its configuration, and thus there is a problem that the stability of measurement is poor.

[0006]

As described above, the conventional magnetic field applying means of the magnetic force microscope has drawbacks that it has a limitation in observation and inferior stability of measurement.

The present invention has been made in view of the above circumstances, and aims to promote diversification of observation modes by ensuring a high magnetic field environment and enabling highly accurate setting of the magnetic field environment. It is an object of the present invention to provide a vertical magnetic field applying device for a magnetic force microscope.

[0008]

According to the present invention, which is arranged in a microscope body, a second pole piece has a predetermined gap with respect to a first pole piece having an insertion hole. And a core made of a magnetic material, which is disposed so as to face each other, and is wound around the first and second pole pieces of the core, respectively. The core and the first and second pole pieces cooperate with each other. A coil that operates to form a magnetic circuit, drive control means that drives and controls the coil to generate a vertical magnetic field in cooperation with the first and second pole pieces, and the first and the first cores. A stage on which a sample disposed between two pole pieces is mounted, a stage driving means connected to the stage through an insertion hole of the first pole piece, for adjusting the movement of the stage, and a magnetic probe portion. Facing the stage It is one that location, non-magnetic material made of a holder member which is separately arranged with the core, and the coil constitute a vertical magnetic field applying device for a magnetic force microscope and a cooling means for thermal control.

According to the above construction, the magnetic probe portion is separated from the core forming the magnetic circuit by the holder member, the coil is thermally controlled by the cooling means, and the first core of the core is used.
The second pole piece and the second pole piece can be arranged close to each other with the stage and the magnetic probe portion sandwiched therebetween. This allows
Forming a highly accurate high magnetic field while preventing the sample-probe distance from fluctuating due to the deformation of the core that constitutes the magnetic circuit due to the magnetostriction phenomenon and effectively preventing the sample from being affected by heat. can do.

Therefore, in a desired magnetic field range, high-resolution magnetic domain observation such as measurement of the difference amount (difference magnetic image) of the magnetic field change of the magnetic domain of the sample by the magnetic force microscope becomes possible, which contributes to the promotion of diversification of observation modes. It becomes possible to do.

Further, according to the present invention, the second pole piece is arranged in the microscope body, and the second pole piece is arranged so as to face the first pole piece having the insertion hole with a predetermined gap. A core made of a magnetic material and wound around the first and second pole pieces of the core, respectively. A coil forming a circuit; drive control means for driving and controlling the coil to generate a vertical magnetic field in cooperation with the first and second pole pieces;
And a stage on which a sample is mounted between the second pole piece, stage driving means connected to the stage through an insertion hole of the first pole piece, and moving and adjusting the stage, and a magnetic probe section. Is arranged to face the stage, and the magnetic probe portion is hermetically accommodated together with the first pole piece so that a vacuum environment can be formed, and is a holder made of a non-magnetic material and arranged separately from the core. A vertical magnetic field applying device for a magnetic force microscope was configured by including a member and a cooling unit that thermally controls the coil.

According to the above construction, the magnetic probe portion is hermetically accommodated by the holder member, the magnetic probe portion is separated from the core, and the coil constituting the magnetic circuit is thermally controlled by the cooling means. Moreover, it becomes possible to dispose the first and second pole pieces of the core close to each other, with the stage and the magnetic probe portion sandwiched therebetween. As a result, in a vacuum environment, while preventing fluctuation due to magnetostriction between samples,
It is possible to form a high-precision high magnetic field while effectively preventing the influence of heat on the sample.

Therefore, in a desired magnetic field range in a vacuum environment, high-resolution magnetic domain observation such as measurement of a difference amount (difference magnetic image) of the magnetic field change of the magnetic domain of the sample by a magnetic force microscope becomes possible, and the observation form is diversified. It becomes possible to contribute to promotion.

[0014]

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

FIG. 1 shows a vertical magnetic field applying apparatus for a magnetic force microscope according to an embodiment of the present invention.
It is assembled and arranged on the microscope main body 9 constituting the magnetic force microscope shown in FIG. Therefore, in FIG. 1, the same parts as those in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, the microscope main body 9 is provided with a core 21 formed of, for example, soft iron so as to cover the stage 20 for mounting the sample. Inside the core 21, first and second pole pieces 22 and 23 are provided so as to face each other with a predetermined gap.

Of these, the first pole piece 22 is formed in a hollow shape by forming an insertion hole 221 on the shaft facing the second pole piece 23, and the insertion hole 221 has a hollow shape.
The actuating portion 241 of the actuator 24, which constitutes the stage driving means and is projected from the insertion hole 91 of the microscope body 9, is inserted. Then, the operating portion 2 of the actuator 24
The stage 20 is attached to 41. As a result, when the actuator 24 is driven via the driving unit (not shown), the stage 20 is finely adjusted in the three axial directions by the operating unit 241.

On the other hand, the second pole piece 23 is provided with a screw portion 231 constituting an adjusting means around the second pole piece 23, and the screw portion 231 is screwed into a screw hole 211 provided in the core 21 so as to be freely screwed. It And the second pole piece 23
An operation handle 25 for screwing adjustment is provided at the base end of the. As a result, when the operation handle 25 is rotationally operated, the screw portion 231 of the second pole piece 23 is screw-adjusted to the screw hole 211 and is moved and adjusted in the first pole piece direction (stage direction). .

Further, in the core 21, the portion where the second pole piece 23 is arranged is substantially orthogonal to the first pole piece direction (stage direction) via the operation mechanism portion 26 constituting the moving operation means. , Is provided so as to be movable in the paper surface direction, for example. As a result, when the operating mechanism 26 is rotated in the direction of the arrow, the second pole piece 23 is moved to a first position facing the stage 20 and a second position not facing the stage 20, thus providing a new position. Stage 2 of sample 10
It can be attached to and detached from 0.

Further, the first and second pole pieces 2
Coils 27 and 28, which form electromagnets, are wound around the circumferences of 2 and 23, respectively. The coils 27 and 28 are mounted in the core 21, and a drive control section 29 constituting drive control means is connected to each drive signal input end thereof.
As a result, the coils 27 and 28 are selectively driven and controlled by the drive control unit 29, and the first and second coils are driven as shown in FIG.
And the second pole pieces 22, 23 to generate a desired magnetic field to apply the desired magnetic field to the sample 10 on the stage 20.

Heat control cooling units 30 and 31 constituting cooling means are thermally coupled and assembled to the coils 27 and 28, respectively. A working medium circulating unit 32 is connected to the cooling units 30 and 31, and a working medium such as water is circulated and supplied through the working medium circulating unit 32 to generate a heat quantity associated with the driving of the coils 27 and 28. Take away and control the heat.

A holder member 33 made of a non-magnetic material such as non-magnetic stainless steel is arranged in the core 21 to fix the magnetic probe 11. The holder member 33 is separately arranged so as not to come into contact with the core 21 in order to exclude that the sample-probe distance is affected by the deformation of the magnetostriction of the core 21. In addition, the holder member 33
Is attached to the microscope body 9 at the front surface (or rear surface) of the core 21 so that the core 21 is not cut. And
A probe mounting portion 331 is detachably provided on the other end of the holder member 33 via a screw 34, and the magnetic probe portion 11 of the magnetic force microscope is mounted on the stage 20 at the probe mounting portion 331. It is attached so as to face the sample 10 mounted on the.

With the above structure, the first and second pole pieces 22 and 23 in the core 21 are arranged so as to face each other with the stage 20 and the magnetic probe portion 11 sandwiched therebetween. For example, the second pole piece 23 and the magnetic probe needle are arranged. The part 11 and the sample 10 on the stage 20 can be brought close to each other by 20 mm or less.
Thereby, the core 21, the first and second pole pieces 2
An electromagnet composed of 2, 23 and coils 27, 28 can generate a high vertical magnetic field of up to about ± 10 kOe in the core 21.

Here, in the magnetic probe portion 11 constituting the measurement system of the magnetic force microscope, the core member 21 is held by the holder member 33.
And are separated from each other. Further, the stage 20 and the actuator 24 have the insertion holes 221 of the first pole piece 22.
It is separated from the core 21 by passing it through. The heat amount of the coils 27, 28 due to the driving is radiated by the cooling units 30, 31 and the working medium circulation unit 32, and the coils 27, 28 are thermally controlled to the initial state. This prevents variation in the sample-probe distance due to magnetostrictive deformation of the core 21, and
The influence of heat on the sample 10 is effectively prevented.

In this state, the coils 27, 28 are
When driven and controlled by the drive control unit 29, forms a magnetic field environment in a desired magnetic field range in the core 21 in cooperation with the first and second pole pieces 22 and 23 (see FIG. 2). .

In this magnetic field environment, the magnetic probe 11
In the magnetic field environment, the leakage magnetic field from the sample 10 to which the vertical magnetic field is applied repels or is attracted to the sample 10, and the amount of deflection is measured by the photodetector 13 (see FIG. 4). To be detected. Based on the detection information of the photodetection unit 13, the difference amount of the magnetic field change of the magnetic domain of the sample 10 (differential magnetic image) is observed with high resolution of 10 nm or less.

At this time, in the stage 20, the actuator 24 is selectively driven by the driving section (not shown) as described above, and the magnetic probe section 1 is driven by the operating section 241.
The position of the sample 10 with respect to the magnetic probe 11 is set to a desired observation position by being slightly moved so as to face 1.

The observation of the magnetic domain structure of the sample 10 is carried out by controlling the driving of the coils 27 and 28 by the drive control unit 29 within the above magnetic field range to determine the strength of the vertical magnetic field applied to the sample 10 on the stage 20. It is performed while changing the polarity or setting the polarity variably.

When replacing the sample 10 or the magnetic probe portion 11 on the stage 20, first, the operation mechanism portion 26 is rotated in the direction of the arrow. Then, a part of the core 21 to which the second pole piece 23 is attached is rotatively moved around the operation mechanism section 26 as a rotation axis, and the second pole piece 23 is separated from the stage 20 at a second position. Be moved to.

Here, the probe mounting portion 33 of the holder member 33
1 is opened to expose the probe mounting portion 331, and the screw 34 is loosened and removed by using this opening, and the probe mounting portion 331 is removed from the holder member 33. In this state, the stage 20 in the holder member 33 can be seen from the outside, and the sample 10 mounted on the stage 20 can be seen.
Alternatively, the magnetic probe 11 is replaced, and after the replacement,
The probe attachment portion 331 is attached to the holder member 33 using the screw 34.

Next, the operation mechanism section 26 is inverted to rotate a part of the core 21 in the opposite direction to move the second pole piece 23 to the first position facing the stage 20, In this state, the sample 1 is again subjected to the above-mentioned observation procedure.
Magnetic domain observation of 0 is performed. At this time, the operation handle 25 is operated as necessary to adjust the position of the second pole piece 23 in the stage direction.

As described above, in the vertical magnetic field applying device for the magnetic force microscope, the core 21 is provided with the first and second pole pieces 2.
2 and 23 are provided so as to face each other, and an insertion hole 231 is provided in one of the first pole pieces 23. Through the insertion hole 231, the first pole piece 22 and the second pole piece 23 are inserted.
And the magnetic probe 11 and the stage 20 via a holder member 33 made of a non-magnetic material, and the magnetic probe 11 and the core 21 are separated by the holder member 33, and The coils 27 and 28 are configured to be thermally controlled via the cooling units 30 and 31.

According to this, the first and second parts in the core 21 are
The pole pieces 22 and 23 can be arranged close to each other with the stage 20 and the magnetic probe portion 11 sandwiched therebetween, and the distance between the sample 10 and the magnetic probe portion 11 varies with magnetostriction deformation of the core 21. It is possible to form a highly accurate and high magnetic field while preventing the influence of heat on the sample 10 effectively.

As a result, in a magnetic field environment in a desired high magnetic field range, the magnetic domain of the sample 10 using a magnetic force microscope can be measured with high accuracy, and the difference amount of the magnetic field change (differential magnetic image) can be measured at 10 nm or less. Can be observed with high resolution and high precision, and can contribute to promotion of diversification of the observation form.

Further, according to this, a hollow first pole piece 22 is arranged in the core 21 so as to face the second pole piece 23 to form a magnetic circuit, and the first pole piece 22 is formed. By arranging the actuating portion 241 of the actuator 24 and the stage 20 constituting the magnetic force microscope through the insertion hole 221 of
A lightweight structure can be realized.

In the above embodiment, the holder member 3
The probe mounting portion 331 of No. 3 is detachably arranged using the screw 34, and is configured to be removed when the sample 10 and the magnetic probe portion 11 mounted on the stage 20 are replaced. However, the present invention is not limited to this, and by changing the shape of the holder member 33, the probe mounting portion 331 is not separable, and the sample 10 is replaced with the stage 20 and the magnetic probe portion is used. It is also possible to configure so that the replacement work of 11 is possible.

Further, the present invention is not limited to the above-described embodiment, but in the case of observing in both atmospheric environment and vacuum environment, for example, it is constructed as shown in FIG. In this embodiment, it is possible to promote the certainty of the separation and arrangement and further promote the diversification of the observation form as compared with the above-described embodiments. However, in FIG. 3, the same parts as those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, in FIG. 3, the first pole piece 40 provided with the insertion hole 401 is formed separately from the core 21, and the first pole piece 40 is formed by the stage 20 and the actuator 24. Working part 24
The holder member 42 formed of a non-magnetic material such as non-magnetic stainless steel via the O-ring 41 in a state in which 1 is assembled.
Interior decoration.

The holder member 42 is detachably attached using a screw 44, for example, with a probe attachment portion 421 formed of a similar non-magnetic material at the tip portion thereof with an O-ring 43 interposed. On the inner wall of the probe mounting portion 421, the magnetic probe portion 11 is mounted and arranged so as to face the stage 20.

The holder member 42 is attached so that its base end portion covers the insertion hole 91 of the microscope body 9. At this time, the base end of the first pole piece 40 is hermetically attached to the microscope body 9 using, for example, an O-ring 45. The coil 27 is wound around the holder member 42. Thereby, the holder member 4
2, the first pole piece 40 is arranged so as to face the second pole piece 23 in a state where the stage 20, the actuating portion 241 of the actuator 24, and the magnetic probe portion 11 which are internally mounted are separated from the core 21.

Here, the inside of the holder member 42 is communicated with the suction drive side of a vacuum pump (not shown) arranged in the microscope body 9 through the insertion hole 91 of the microscope body 9, and the vacuum pump (see FIG. When (not shown) is driven, the sealed internal air is exhausted through the insertion hole 91 and a vacuum environment is set.

With the above structure, when performing observation in a vacuum environment, the vacuum pump (not shown) is driven. Then, the vacuum pump (not shown) is attached to the holder member 4
The air inside 2 is sucked through the insertion hole 91 of the microscope body 9, and the inside of the holder member 42 is set to a vacuum environment.

In this way, with the inside of the holder member 42 set to the vacuum environment, the drive control section 29 drives and controls the coils 27 and 28, and cooperates with the first and second pole pieces 23 and 40. By setting the magnetic field strength and the polarity thereof in a desired high magnetic field range, a desired vertical magnetic field is generated in the core 21.

In this magnetic field environment, the magnetic probe 11
Is separated from the core 21 and is repulsed or attracted to the sample 10 due to a leakage magnetic field from the sample 10 in a vacuum environment and a magnetic field environment.
The amount of bending is detected by the photodetector 13 (see FIG. 4). Based on the detection information of the photodetection unit 3, the difference amount of the magnetic field change of the magnetic domains of the sample 10 exposed to the vacuum environment (differential magnetic image) is observed with high resolution of 10 nm or less.

When replacing the sample 10 or the magnetic probe 11 on the stage 20, first, the vacuum pump (not shown) is stopped and the inside of the holder member 42 is set to the atmospheric environment. . In this atmospheric environment, the operation mechanism section 26 is rotationally operated as described above to linearly move a part of the core 21 together with the second pole piece 23, and the second pole piece 23 is separated from the stage 20. Move it to the second position.

Here, the probe mounting portion 42 of the holder member 42
1 is opened to expose the probe mounting portion 421, the screw 34 of the probe mounting portion 331 is loosened and removed by using this opening, and the probe mounting portion 331 is removed from the holder member 33. In this state, the stage 20 can be seen from the outside, and the sample 10 mounted on the stage 20 can be seen.
Alternatively, replace the magnetic probe portion 11 of the probe mounting portion 421,
After the replacement, the probe mounting portion 421 is mounted again on the holder member 42 using the screw 44.

Next, the operating mechanism 26 is operated to operate the core 21.
Is moved to a first position where the second pole piece 23 faces the stage 20, and in this state, the magnetic domain observation of the sample 10 is performed again by the observation procedure described above. On this occasion,
The operation handle 25 is adjusted as necessary to adjust the position of the second pole piece 23 in the stage direction.

When observing in an atmospheric environment,
When the driving of the vacuum pump (not shown) is stopped, the inside of the holder member 42 is set to the atmospheric environment. Here, the observation is performed with a high resolution such that the difference amount (difference magnetic image) of the magnetic field change of the magnetic domain of the sample is 10 nm or less by the same procedure as the observation procedure in the vacuum environment.

Even in the observation state of the sample 10 in the atmospheric environment, the sample 10 on the stage 20 and the magnetic probe portion 11 are replaced by the same procedure.

In each of the above-described embodiments, the core 21 and the first and second pole pieces 22 (40) and 23 are made of soft iron. However, the present invention is not limited to this. It is possible to use various magnetic materials such as FeCo. In addition, the first and second core 21
The pole pieces 22 (40) and 23 and other parts may be made of different magnetic materials.

For example, the first and second pole pieces 22
By using FeCo as the magnetic material forming (40) and 23 to further increase the number of turns of the coils 27 and 28 and to increase the supply current, a higher vertical magnetic field can be obtained. In principle, it is confirmed that it is possible to generate a magnetic field up to about 20 koe.

Therefore, the present invention is not limited to the above-described embodiment, and other various modifications can be carried out at the stage of carrying out the invention without departing from the spirit thereof. Further, the embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, the problem described in the section of the problem to be solved by the invention can be solved, and the effect described in the effect of the invention can be obtained. When the above is obtained, the configuration in which this constituent element is deleted can be extracted as the invention.

[0054]

As described in detail above, according to the present invention, a high magnetic field environment can be secured, and a highly accurate setting of the magnetic field environment can be realized to promote the diversification of observation modes. A vertical magnetic field application device for a magnetic force microscope can be provided.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a vertical magnetic field application device of a magnetic force microscope according to an embodiment of the present invention.

FIG. 2 is an operation explanatory view shown for explaining an observation operation of a magnetic domain structure of the sample of FIG.

FIG. 3 is a configuration diagram showing a vertical magnetic field applying apparatus for a magnetic force microscope according to another embodiment of the present invention.

FIG. 4 is a configuration diagram shown for explaining a schematic configuration of a magnetic force microscope to which the present invention is applied.

[Explanation of symbols]

9… Microscope body 91 ... Insertion hole 10… Sample 11 ... Magnetic probe 12 ... Light source 13 ... Photodetector 20 ... Stage 21 ... Core 211 ... Screw hole 22 ... The first pole piece 221 ... Insertion hole 23 ... Second pole piece 231 ... Screw part 24 ... Actuator 241 ... Working part 25 ... Operation handle 26 ... Operation mechanism section 27, 28 ... Coil 29 ... Drive control unit 30, 31 ... Cooling unit 32 ... Working medium circulation unit 33 ... Holder member 331 ... Tip mounting part 34 ... Screw 40 ... the first pole piece 401 ... Insertion hole 41, 43, 45 ... O-ring 42 ... Holder member 421 ... Tip mounting part 44 ... screw

Claims (5)

[Claims] 1. A magnetic material, which is arranged in a microscope main body, in which a second pole piece is opposed to a first pole piece provided with an insertion hole with a predetermined gap. A core, which is wound around each of the first and second pole pieces of the core, and forms a magnetic circuit in cooperation with the core and the first and second pole pieces. A coil, drive control means for driving and controlling the coil to generate a vertical magnetic field in cooperation with the first and second pole pieces; and a coil disposed between the first and second pole pieces of the core. A stage on which a sample to be mounted is mounted, a stage drive means connected to the stage through an insertion hole of the first pole piece, and a stage for driving and adjusting the stage, and a magnetic probe portion arranged to face the stage. And before Core and a separating arrangement is a non-magnetic material made of the holder member has, magnetic force microscopy vertical magnetic field application device, characterized in that said coil comprises a cooling means for thermal control. 2. A magnetic material, which is arranged in a microscope main body, in which a second pole piece is arranged to face a first pole piece provided with an insertion hole with a predetermined gap. A core, which is wound around each of the first and second pole pieces of the core, and forms a magnetic circuit in cooperation with the core and the first and second pole pieces. A coil, drive control means for driving and controlling the coil to generate a vertical magnetic field in cooperation with the first and second pole pieces, and is arranged between the first and second pole pieces of the core. A stage on which a sample is mounted, a stage driving unit that is connected to the stage through an insertion hole of the first pole piece, and that adjusts the movement of the stage, and a magnetic probe unit are arranged to face the stage. Yes, the porcelain A holder member made of a non-magnetic material, which encloses the probe portion together with the first pole piece so that a vacuum environment can be formed, and which is separately arranged from the core, and a cooling means for thermally controlling the coil. A vertical magnetic field application device for a magnetic force microscope. 3. A moving operation means for moving the second pole piece between a first position that faces the first pole piece and a second position that does not face the first pole piece. The perpendicular magnetic field application device of the magnetic force microscope according to 1 or 2. 4. The magnetic force microscope according to claim 1, further comprising adjusting means for moving and adjusting the second pole piece in the direction of the first pole piece. Vertical magnetic field application device. 5. The holder member is provided such that the assembly portion of the magnetic probe portion can be separated.
5. A vertical magnetic field applying device for a magnetic force microscope according to any one of 4 to 4.