JP3126527B2 - Information processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus using or applying the STM principle.

[0002]

2. Description of the Related Art In recent years, with the development of the information-oriented society, the development of large-capacity memory technology has been carried out. Recently, a recording / reproducing apparatus using or applying the principle of a scanning tunneling microscope (hereinafter abbreviated as STM) has appeared.

The STM utilizes the fact that a tunnel current flows when a metal probe (tunnel tip) is brought close to a distance of about 1 nm by applying a voltage between conductive materials. This current is sensitive to a change in the distance between the two. By scanning the probe electrode so as to keep the tunnel current constant, it is also possible to read various information on all electron clouds in the real space. The resolution in the in-plane direction at this time is 0.1
nm. Therefore, if the principle of the STM is applied, it is possible to perform high-density recording / reproduction sufficiently in the atomic order (sub-nanometer). For example, JP
In the information recording / reproducing apparatus disclosed in Japanese Patent Application No. 1-80536, writing is performed by removing atomic particles adsorbed on the medium surface by an electron beam or the like, and the data is reproduced by STM.

Switching characteristics of voltage and current as a recording layer
Materials that have a memory effect on
Recording using thin layers of organic compounds and chalcogen compounds
A method of performing reproduction by STM has been proposed (Japanese Unexamined Patent Publication No.
JP-A-3-161552, JP-A-63-161553
Gazette). According to this method, the bit size of the recording
If it is 10 nm, 10¹²bit / cm^Two Things large capacity
Recording and playback are possible. In addition, for the purpose of miniaturization,
Electrodes are formed side by side on a semiconductor substrate
A device for displacing and recording on a recording medium to be changed has been proposed.
(JP-A-62-281138, JP-A-1-196)
No. 751). For example, 1cm ^Two Corner Silicone
2500 probe electrodes on a 50 × 50 mat
Multi-probe head with a click arrangement and the above-mentioned memory
By combining materials with effects, one probe
Digit with 400Mbit per unit and total recording capacity 1Tbit
Recording and reproduction of total data.

Further, in an information recording / reproducing apparatus using or applying the above-mentioned STM principle, the alignment of a recording medium surface and a plurality of probe electrode surfaces with respect to a scanning surface (inclination correction) is performed, for example, by using a specific probe electrode. Is used as a probe electrode for surface matching, and the tunnel current detected by the probe electrode is made equal.

[0006] The term "scanning surface" as used herein means a surface drawn by the tips of the probe electrodes when the plurality of probe electrodes and the recording medium are relatively moved, and the probe electrode surface is formed by the tips of the plurality of probe electrodes. It is the side that is.

[0007]

However, if there is a variation in the height direction of the probe electrodes used for performing the above-mentioned surface alignment, the surface to be originally subjected to the surface alignment (the surface of the recording medium with respect to the scanning surface and a plurality of probe electrodes) is required. Face) could not be aligned.

For example, if there is a variation in the height direction of ± 10 μm due to warpage in the surface-matching probe electrode, it will be inclined by about 0.2 ° from the surface to be originally aligned.

Therefore, there are the following problems.

(1) When recording / reproducing information, a mechanism and an electric circuit for largely moving the probe electrode in the direction perpendicular to the surface of the recording medium for correcting the tilt are required, and the apparatus becomes complicated.

[0011] Further, if the surface of the probe electrode for surface alignment has a large variation due to the warp and the inclination of the surface to be aligned is large, (2) the movable range of the moving mechanism of the probe electrode is exceeded, and the information cannot be recorded / reproduced. .

(3) Since the moving mechanism of the probe electrode is frequently used, the life of the moving mechanism is shortened.

(4) A piezoelectric material is mainly used for the mechanism for moving the probe electrode. However, the piezoelectric material has a hysteresis and it is difficult to control a precise movement when driving for tilt correction. A high-voltage power supply or the like is required, and the response speed of the probe electrode is reduced.

Further, in the case of performing parallel data recording / reproducing with a plurality of probes in the above-mentioned conventional example, since there is a variation in shape and size due to an error in the process of producing the probe, it is necessary to correct the variation. In addition, it is necessary to control each probe at the time of recording and reproduction.
The order of 00 or 1000 leads to an increase in the scale of the control system.

[0015]

The present invention has been made in view of the above problems.
A is, the shape between irregularities and individual probe electrodes with individual probe electrode surface of the recording medium can be a relative distance between the tip and the recording medium surface of the probe electrode at a constant regardless of the variation in size To provide an information processing device capable of
For the purpose .

[0017]

[0018]

[0019]

[0020]

[0021]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a recording medium, a plurality of probe electrodes arranged opposite to the recording medium, and a plurality of probes.
A support for supporting an electrode, and the recording medium of the support
Means for correcting an inclination with respect to the recording medium, means for relatively displacing the recording medium and the probe electrode in an in-plane direction parallel to the recording medium surface, and recording and reproduction in the presence of the probe electrode on the recording medium. An information processing apparatus having means for performing the above-mentioned steps, wherein the plurality of probe electrodes use an elastic body having an elastic constant smaller than the elastic constant of the surface of the recording medium as a member constituting each probe electrode, and the recording medium and that an elastic member having a larger elastic constant than the elastic constant of the surface with is constructed by arranging the respective plurality predetermined position, the correction means
Are a plurality of probes using an elastic body having a large elastic constant.
So that the signal detected from the lobe electrode is constant.
It is characterized in that the inclination between the support and the recording medium is corrected .

[0022]

The probe electrode for use in a recording medium reproducing the invention as (action) The above-described uses an elastic body having a smaller elastic constant than the elastic constant of the recording medium surface. FIG. 16 is a diagram showing the state of the tips of a plurality of probe electrodes and the surface of a recording medium in the apparatus of the present invention.

Therefore, when a plurality of probe electrodes are brought close to the recording medium, as shown in FIG.
The elastic deformation amount of the elastic body 303 supporting each of the tunnel tips 302 becomes larger than the elastic deformation amount of the above. As a result, the distance between the tip of the tunnel tip and the surface of the recording medium can be controlled without controlling the distance between the individual probe electrodes and the surface of the recording medium, regardless of irregularities on the surface of the recording medium and variations in the shape and size between the individual probe electrodes. Is maintained in a constant contact state.

A plurality of probe electrodes using an elastic body having an elastic constant larger than the elastic constant of the recording medium are used for tilt correction.

When the recording medium approaches a certain probe electrode by a distance of about 1 nm, a tunnel current flows between the recording medium and the tunnel tip. In addition, since the probe electrode for inclination correction has an elastic constant larger than that of the recording medium surface,
When the substrate supporting the contact electrodes is inclined with respect to the recording medium, the forces exerted by the respective probe electrodes are different, so that the recording medium is elastically deformed, and the distance between the tip of the tunnel tip and the recording medium base electrode 305 is the magnitude of the force. It changes according to.

Therefore, the magnitude of the detected tunnel current is also different. Since the balance of the tunnel current indicates the degree of inclination between the substrate supporting the probe electrode and the recording medium, the probe is controlled by controlling the tunnel current detected from the probe electrode for inclination correction to be the same. The parallelism between the substrate supporting the electrodes and the surface of the recording medium is maintained. Since the magnitude of the tunnel current indicates the magnitude of the force acting between the tunnel chip and the recording medium, if the value does not exceed a certain threshold, the magnitude of the magnitude of the force acting between the tunnel chip and the recording medium is reduced. Control becomes possible.

The probe electrode for inclination correction and the probe electrode for recording / reproducing are manufactured by the same process, and the same substrate 30 is used.
4, the control of the positional relationship between the inclination-correcting probe electrode and the recording medium also controls the positional relationship between the recording / reproducing probe electrode and the recording medium.

As a result, it is possible to control the variation in the force applied to each of the probe electrodes used for recording and reproduction to be within a certain fixed range, and to control the magnitude of the force to a set value.

The recording medium being recorded / reproduced by the above operation,
Even if the material of the probe electrode is a material that is easily worn or broken by the force acting between the tunnel tip and the recording medium, it is possible to prevent a force greater than the breaking threshold from being applied.

[0031]

Hereinafter, embodiments of the present invention will be described.
A reference example will be given before this description.

(First Reference Example) FIG. 1 is a diagram showing a basic configuration of an apparatus of the present embodiment . In FIG. 1, reference numeral 1 denotes a plurality of probe electrodes formed by a micromechanics technique, and 2 denotes a plurality of probe electrodes. A probe electrode attachment for setting the tilt mechanism, a tilt mechanism for changing the inclination of a plurality of probe electrodes, and a Z-direction fine / coarse movement mechanism for finely / coarsely moving a plurality of probe electrodes in the Z direction. . 5 is a recording medium, 51 is a substrate obtained by polishing glass, 52 is a base electrode formed by forming Cr (undercoat layer) and Au on the substrate 51 by a vacuum evaporation method,
Reference numeral 53 denotes a graphite (HOPG) recording layer. The recording layer 53 is bonded on the base electrode 52 with a conductive adhesive,
The recording / reproducing area on the surface of the recording layer is smoothed on the atomic order by cleavage. Reference numeral 6 denotes a tilt mechanism for changing the inclination of the recording medium 5, and reference numeral 7 denotes an XY direction fine / coarse movement mechanism for finely / coarsely moving the recording medium 5 in the XY directions. Reference numeral 8 denotes an interface for connecting the recording / reproducing device to an external device, and performs input / output of write / read information, output of status, input of a control signal, and output of an address signal. 80 is a control circuit for centrally controlling the interaction between the blocks of the recording / reproducing apparatus, and 81 is a control circuit for writing / reading information (data).
A writing / reading circuit 82 for writing / reading in accordance with an instruction from the device; a command signal from the writing / reading circuit 82 applies a pulse voltage for writing between the plurality of probe electrodes 1 and the recording medium 5 to write data; A bias circuit for applying a voltage for read-in or reading; 83, a tunnel current detection circuit for detecting a current flowing between the plurality of probe electrodes 1 and the recording medium 5 during recording / reproduction; 84, an instruction from the control circuit 80 or the like; The tunnel current detection circuit 83 and the position detection circuit 8
A positioning circuit 85 for determining the positions of the plurality of probe electrodes 1 and the recording medium 5 based on the signal 8, and a servo 85 for controlling the positions of the plurality of probe electrodes 1 and the recording medium 5 based on the servo signal from the positioning circuit 84. A servo circuit, 86 is a Z-direction drive circuit for driving the Z-direction fine movement / coarse movement mechanism 4 of the plurality of probe electrodes 1 in accordance with the signal of the servo circuit 85, and 87 is an XY-direction fine movement of the recording medium 5 in accordance with the signal of the servo circuit 85. An XY direction drive circuit for driving the coarse movement mechanism 7; 89, a tilt mechanism drive circuit for driving the tilt mechanisms 3, 6 in accordance with a signal from the servo circuit 85; 90, a plurality of probe electrodes 1;
Is a tunnel current detection circuit for detecting a tunnel current flowing through a probe electrode used when the substrate is brought closer to the recording medium 5. In FIG. 1, the control circuit 80, the write / read circuit 81,
Although only one bias circuit 82 and one tunnel current detector 83 are described, actually, the same number of probe electrodes are used.

FIG. 2 is a sectional view showing an example of the configuration of a probe electrode which is a main component of the apparatus of the present embodiment . Reference numeral 11 denotes a tunnel chip for applying a voltage to a recording layer by applying a tunnel current or a recording signal. Reference numeral 12 denotes a cantilever for moving the tunnel tip in the Z direction, and is formed by a micromechanics technique. By applying an arbitrary voltage to the electrodes 14 and 15, the cantilever can be displaced by the electrostatic force. Reference numeral 16 denotes a probe electrode having a tunnel tip on a cantilever, and reference numeral 13 denotes a substrate on which the probe electrode is formed.

FIG. 3 is a plan view of a substrate on which a plurality of probe electrodes used in the apparatus of the present embodiment are formed, as viewed from above. Ten probe electrodes 16 are provided in the X direction and 20 probe electrodes are provided in the Y direction.
A total of 200 are arranged. Each of the probe electrodes 16 is provided with a wiring for detecting a tunnel current from the tunnel tip 11 or applying a voltage to a recording layer for a recording signal, and each is connected to a tunnel current detector 83 and a bias circuit 82. I have. Reference numeral 17 denotes a substrate for a plurality of probe electrodes. The row number of each probe electrode is described on the left side of the substrate 17 in the drawing, and the column number is similarly written on the upper side of the drawing.

In this example , the position of the three probe electrodes [(10, A), (1, J), (20, J)] and the probe electrodes shown in the ellipse are adjusted in the Z direction. Used for

A plurality of probe electrodes shown in FIG. 3 were mounted on the apparatus shown in FIG. FIG. 4 is a diagram showing the tilt mechanism of the present embodiment . The mounting is performed by fixing the substrate on which a plurality of probe electrodes are formed to the probe electrode attachment 2 using an adhesive, and the individual probe electrodes 1
6 and the connection to the tunnel current detector 83 and the bias circuit 82 as shown in FIG. As shown in FIG. 4, the tilt mechanism 3 shown in FIG. 1 includes a leaf spring 31 for fixing the probe electrode attachment 2 and laminated piezoelectric elements 32 to 34 for correcting the inclination of the plurality of probe electrodes 1 (in FIG. It is located behind the piezoelectric element 32 and is not shown), and is constituted by a steel ball 35 that concentrates the load of the laminated piezoelectric elements 32 to 34 at one point. The multilayer piezoelectric elements 32 to 34 are arranged to expand and contract in the Z-axis direction,
One of the directions of expansion and contraction is fixed to the leaf spring 31 with an adhesive, and the other is in contact with the steel ball 35. Also. Three laminated piezoelectric elements 32 to 34 are used, and three Z
Direction adjustment probe electrodes (10, A), (1,
J), (20, J). The displacement sensitivity of this piezoelectric element is 6.5 μm / 100V.

The apparatus used in the present embodiment is composed of a plurality of probe electrodes 1.
Are fixed in the XY directions, and the recording medium 5 is slightly moved in the XY directions.

When performing the surface alignment, the probe electrodes (10, A), (1, J), (20,
The tilt mechanism 3 having the above-described configuration is adjusted so that the tunnel currents detected by J) become equal.

However, if the specific probe electrode used as the Z-direction position adjustment probe electrode has a variation in the height direction due to warpage, correct surface matching cannot be performed.

Therefore, first, it is necessary to detect variations in the height direction of the Z-direction position adjustment probe electrode.

First, the details of a method for detecting the degree of variation in the height direction due to the warpage of the Z-direction position adjustment probe electrode will be described.

The Z direction position adjustment probe electrodes (10,
A), (1, J), and (20, J) are applied with a voltage of 1 mV, and the cantilever is displaced by 1 nm toward the recording medium. It is assumed that the Z-direction position adjustment probe electrode is warped in the recording medium direction and has a tilt axis at a position parallel to the substrate 17 shown in FIG.

The Z-direction coarse adjustment mechanism 4 adjusts the Z-direction position adjusting probe electrodes (10, A), (1, J), (20,
In J), the recording medium 5 is brought close to the recording medium 5 until a tunnel current of about 10 ^-8 A is detected.

A plurality of probe electrodes as shown in FIG. 3 are rotated around the Y axis by using a tilt mechanism. At this time, it is prevented from rotating around the X axis. More specifically, the laminated piezoelectric element 33 shown in FIG. 4 disposed directly above the Z-direction position adjustment probe electrode (10, A) is contracted at 0.5 angstrom intervals. At the same time, the laminated piezoelectric elements 32 and 34 shown in FIG. 4 disposed directly above the Z-direction position adjustment probe electrodes (1, J) and (20, J) are arranged at the same interval (0.5 angstrom interval). Extend. As a result, the multiple probe electrodes are on the right side (row J in FIG. 3).
Comes closer to the recording medium, and the left side (row A in FIG. 3) moves away.

FIG. 5 shows the change in the tunnel current detected by the Z-direction position adjustment probe electrodes (10, A), (1, J), (20, J) at this time. FIG. 5 is a diagram showing a change in tunnel current in the device of the present invention.
ΔJ _T 1, ΔJ _T 2, and ΔJ _T 3 in the figure show the increase amount of the tunnel current at the time of tilt. When there is no variation in the height direction among the three Z-direction position adjustment probe electrodes, the absolute value of the increase rate (gradient of the graph) of the tunnel current of each Z-direction position adjustment probe electrode becomes equal.

Therefore, a reference curve that minimizes the amount of correction is selected from the slopes of the three graphs (ΔJ _T 1, ΔJ _T 2, ΔJ _T 3 in this graph), and the tunnel of the remaining Z-direction position adjustment probe electrode is selected. The correction is performed by displacing the probe electrode, to which the voltage has been applied to the Z-direction adjustment probe electrode, in the height direction so that the current increase rate (the slope of the graph) becomes the same.

In the present embodiment , the absolute value of the slope of the other curve is adjusted based on the tunnel current increase curve of the Z-direction position adjustment probe electrode (10, A). Specifically, Z
The probe electrodes (1, J) for adjusting the directional position are about 0.5 angstroms, and the probe electrodes (20,
J) was displaced toward the recording medium side by about 1 Å.

In this example , one of the curves measured as the reference curve is used, but a theoretical curve prepared in advance may be used. In order to make the rate of increase of the tunnel current (gradient of the graph) the same, a voltage was applied to the probe electrode for position adjustment in the Z direction to displace the probe electrode in the height direction. Instead of the displacement, the tunnel current detected at the time of the next surface matching may be corrected as a correction coefficient.

As described above, the Z direction position adjustment probe electrode (1
Since the corrections of (0, A), (1, J), and (20, J) have been completed, the three probe electrodes are used to perform face matching.

First, a plurality of probe electrode surfaces are aligned with the recording medium surface.

Using a tilt mechanism, a plurality of probe electrodes are connected to the laminated piezoelectric element 10 by 10n so that the probe electrode (10, A) for adjusting the position in the Z direction approaches the recording medium first.
m. A bias voltage of 0.5 V is applied between the probe electrode and the recording medium.

First, plane correction in the X direction is performed as shown in FIG. FIG. 6 is a diagram illustrating plane correction in the X direction in the surface matching method in the apparatus of the present example .

As shown in FIG. 6A, the Z-direction position adjusting probe electrode (10, A) is moved by the Z-direction coarse movement mechanism to a position where a tunnel current of about 10 ^-8 A is detected.

Next, as shown in FIG. 6B, the multilayer piezoelectric element 32 is extended, and the Z direction position adjustment probe electrodes (1,
J) is moved until the position of the Z-direction position adjustment probe electrode (10, A) becomes equal to the detected tunnel current. By increasing the voltage applied to the multilayer piezoelectric element 32 by 100 mV (about 10 nm in terms of displacement), the Z-direction position adjustment probe electrode (1, J) is changed to the Z-direction position adjustment probe electrode (10, A). Could be the same as the detected tunnel current.

Next, plane correction is performed in the Y direction as shown in FIG. FIG. 7 is a diagram illustrating the plane correction in the X direction by the surface alignment method in the apparatus of the present example .

As shown in FIG. 7B, the multilayer piezoelectric element 34 is extended from the state shown in FIG. 7A, and the Z-direction position adjusting probe electrode (20, J) is replaced with the Z-direction position adjusting probe electrode ( 10. Move until A) becomes the same as the detected tunnel current. By increasing the voltage applied to the multilayer piezoelectric element by 50 mV (about 5 nm in terms of the amount of displacement), the Z-direction position adjustment probe electrode (20,
J) could be made the same as the tunnel current detected by the Z direction position adjustment probe electrode (10, A). Then Z
Direction position adjustment probe electrode (1, J), (20, J)
And the displacement of the cantilever is returned to the original.

Next, the recording medium surface and the scanning surface are aligned based on the locus shown in FIG. FIG. 8 is a diagram showing a trajectory for aligning the surface of the recording medium with the scanning surface in the apparatus of this embodiment .

First, at any point A on the recording medium 5, the probe electrodes (1
0, A) to the tunnel area.

Then, the Z direction position adjustment probe electrode (1
The recording area S is moved to a point B at one corner while controlling the vertical distance of (0, A). Next, the probe electrode is moved in the order of C, D, and E from the point B while keeping the tunnel area constant along the outer periphery of the recording area S.

FIG. 9 shows the vertical control amount of the probe electrode when the probe electrode is moved along the outer periphery of the recording area S, and the vertical control amount of the probe electrode with reference to the point A shown in FIG. Is shown on the vertical axis. Control is performed to move the probe electrode in a direction approaching the recording medium 5 from the point A to the point D, and control is performed in a direction away from the point D to the point B. That is, in the above-described case, the inclination of the recording medium 5 with respect to the scanning surface of the probe electrode is closest to the scanning surface at point A, followed by points B, C and E, and point D are farthest.

From these results, the tilt mechanisms 3 and 6 as shown in FIG. 1 were used to change the inclination of the recording medium surface and the plurality of probe electrode surfaces while maintaining the parallelism between the plurality of probe electrode surfaces and the recording medium surface. Perform face-to-face matching.

In this state, a recording experiment was performed by driving the XY fine movement mechanism 7 and applying a triangular wave of ± 10 V to the recording medium 5 between an arbitrary tunnel chip / substrate electrode.
Recording and reproduction of information could be performed without sufficient contact of the chip.

In this embodiment , three probe electrodes are used as the Z-direction position adjustment probe electrodes when the plurality of probe electrodes 1 and the recording medium 5 are aligned, but this may be one at each of the four corners. The order of surface matching may be adjusted in the Y direction and then in the X direction.

When the surface of the recording medium and the scanning surface are aligned, the probe electrodes (10, A) for adjusting the position in the Z direction of the plurality of probe electrodes 1 are used as sensors, but any probe section electrodes may be used. Similar results were obtained when the Z-direction position adjustment probe electrode (1, J)) was used as a sensor.

(Second Reference Example) In the apparatus of this example , a plurality of probe electrodes shown in FIG. 3 were mounted on the apparatus shown in FIG. 4 as in the first reference example. The mounting was performed by fixing the substrate of the plurality of probe electrodes to the probe electrode attachment using an adhesive, and the connection between the probe electrodes, the tunnel current detector 83, and the bias circuit 82 was performed using a connector. The tilt mechanism 3 includes a leaf spring 31 for fixing the probe electrode attachment 2 and laminated piezoelectric elements 32 to 34 for correcting the inclination of the plurality of probe electrodes (the piezoelectric element 34 is located behind the piezoelectric element 32 in FIG. (Not shown), and is constituted by a steel ball 35 that concentrates on one point of the load of the laminated piezoelectric element. Multilayer piezoelectric element 32 ~
Numeral 34 is arranged to expand and contract in the Z-axis direction, one of the expansion and contraction directions is fixed to a leaf spring with an adhesive, and the other is a steel ball 3.
5 is touched. The laminated piezoelectric elements 32 to 34 are 3
Each of the probe electrodes is used just above three Z-direction position adjustment probe electrodes (10, A), (1, J), and (20, J). The displacement sensitivity of this piezoelectric element is 6.
5 μm / 100V.

The apparatus used in this embodiment has a structure in which a plurality of probe electrodes are fixed in the XY directions, and the recording medium is finely moved in the XY directions.

In the first reference example, the scanning surface and the recording medium 5 are aligned after the plurality of probe electrodes 1 and the recording medium 5 are aligned, but in this example , the scanning surface and the recording medium 5 are first aligned.
Then, the plurality of probe electrodes 1 and the recording medium 5 were aligned.

A probe electrode (10,
A), (1, J), a voltage of 1 mV is applied to (20, J),
The cantilever is displaced by 1 nm toward the recording medium. In addition,
It is assumed that the Z-direction position adjustment probe electrode is warped in the recording medium direction and has a tilt axis at a position parallel to the substrate 17.

[0069] Detection method and correction method of variation of the Z direction position adjustment probe electrode is the same as the first embodiment.

With the above, the Z direction position adjustment probe electrode (1
Since the corrections of (0, A), (1, J), and (20, J) have been completed, the three probe electrodes are used to perform face matching.

Next, the details of the face matching will be described.

First, the scanning surface and the recording medium 5 are aligned.

A plurality of probe electrodes 1 are moved by using a tilt mechanism so that the multilayer piezoelectric element 33 is moved so that the Z-direction position adjustment probe electrodes (10, A) approach the recording medium first.
Extend by nm.

A bias voltage of 0.5 V is applied between the probe electrode and the recording medium.

The Z-direction position adjustment probe electrode (10, A) and the recording medium 5 are brought closer to an arbitrary point A on the recording medium 5 to the tunnel region. Then, the probe electrode is moved to a point B at one corner of the recording area S while controlling the vertical distance of the probe electrode.
Next, while keeping the tunnel region constant along the outer periphery of the recording region S, the probe electrode is moved from the point B to the points C, D, and E in the same manner.
Move in the order. A mechanism for detecting and correcting the tilt of the recording medium 5 and the scanning surface is the same as the first embodiment.

Next, the plurality of probe electrodes 1 and the recording medium 5 are aligned.

The Z direction position adjustment probe electrode (1,
A voltage of 1 mV is also applied to J) and (20, J), the cantilever is displaced by 1 nm toward the recording medium, and a bias voltage of 0.5 V is applied between the probe electrode and the recording medium.

The method of this surface matching is the same as in the first reference example.

In this state, a recording experiment was performed by driving the XY fine movement mechanism and applying a triangular wave of ± 10 V to an arbitrary tunnel chip / substrate electrode with respect to the recording medium. Recording and reproduction of information could be performed without sufficient contact of the chip.

[0080] (Third Example) FIG. 10 is a plurality of probe electrodes used in the equipment of the present embodiment, are arranged in 10 by one line in the X direction. These probe electrodes were mounted on the device shown in FIG. The configuration of the device is the same as that used in the first reference example and the second reference example, except that the number of laminated piezoelectric elements for correcting the inclination of the plurality of probe electrodes is two. Each of them is installed right above one Z-direction position adjustment probe electrode (A), (J).

The apparatus used in this embodiment has a configuration in which a plurality of probe electrodes are fixed in the XY directions, and the recording medium is finely moved in the XY directions.

The probe electrodes (10,
A), (1, J), and (20, J) are applied with a voltage of 1 mV, and the cantilever is displaced by 1 nm toward the recording medium. It is assumed that the Z-direction position adjustment probe electrode is warped in the recording medium direction and has a tilt axis at a position parallel to the substrate 17.

[0083] Detection method and correction method of variation of the Z direction position adjustment probe electrode is the same as the first embodiment.

As described above, the variation in the height direction of the Z-direction position adjustment probe electrodes (A) and (J) can be corrected, and the two probe electrodes are used to perform surface matching.

Next, the details of the surface matching method will be described.

First, a plurality of probe electrodes are aligned with the surface of the recording medium as shown in FIG. FIG. 11 is a diagram showing the plane correction in the X direction in the surface matching method in the apparatus of the present invention.

A plurality of probe electrodes are extended by 10 nm by using a tilt mechanism so that the Z-direction position adjustment probe electrode (A) approaches the recording medium first. A bias voltage between the probe electrode and the recording medium of 0.
5 V is applied.

Then, as shown in FIG. 11A, the Z-direction position adjusting probe electrode (A) is moved by the Z-direction coarse movement mechanism.
^Is moved to a position where a tunnel current of about 10 ⁻⁸ A is detected.

Next, as shown in FIG. 11B, the multilayer piezoelectric element 32 is extended, and the Z-direction position adjustment probe electrode (J) is the same as the tunnel current detected by the Z-direction position adjustment probe electrode (A). Move until. By increasing the voltage applied to the multi-layer piezoelectric element 32 by 100 mV (about 10 nm in terms of displacement), the tunnel electrode in which the Z-direction position adjustment probe electrode (J) is detected by the Z-direction position adjustment probe electrode (A) is detected. Could be the same as the current.

Next, a Z direction position adjustment probe electrode (J)
Is set to 0 V, and the displacement of the cantilever is restored.

Next, the recording medium surface and the scanning surface are aligned with each other according to the locus shown in FIG. This is the first method
This is the same as the reference example.

A recording experiment was performed by driving the XY fine movement mechanism in the state where the surface matching was completed, and applying a triangular wave of ± 10 V to an arbitrary tunnel chip / substrate electrode with respect to the recording medium. Recording and reproduction of information could be performed without sufficient contact of the tunnel chip.

In this embodiment , the Z-direction position adjusting probe electrode (A) is used as a sensor for aligning the surface of the recording medium with the scanning surface, but any probe electrode may be used as the sensor. Similar results were obtained when was used as a sensor.

Further, as shown in FIG. 10, a plurality of probe electrodes 16 arranged in a straight line may be arranged with the longitudinal direction of the cantilever in the Y direction as shown in FIG. 12, or as shown in FIG. May be arranged in a straight line.

(Example) Next, an example of the present invention will be described. FIG. 14 shows the present invention.
It is a diagram showing a basic configuration of the actual施例of. In this figure, m × n probe electrodes are constituted by m × n cantilevers 101 made of an elastic body and a plurality of tunnel chips 102 supported by them. Among them, three probe electrodes (103, 104, 105) are used for inclination correction, and these inclination correction probe electrodes 103, 1 are used.
04 and 105 respectively include tilt correction driving elements 106, 107, and 107 respectively supported on a support (not shown).
108 are provided. Then, the tilt correction probe electrodes 103, 104, and 105 are brought closer to the recording medium 109 by the tilt correction drive elements 106, 107, and 108. The signal line a is a command signal from the control processor, the signal line b is an XY drive signal, and the signal line c is a vertical drive signal.

The probe electrode used here is manufactured as follows. A 0.3 μm thick SiO ₂ film is formed on the surface of the Si substrate 110 by thermal oxidation. The cantilever for recording and reproduction is 100 μm long and 20 μm wide, and the cantilever for tilt correction is 60 μm long and 40 μm wide. Pattern the cantilever shape. Next, an electric signal wiring pattern to the tunnel chip is formed, and KO is applied from the back surface of the substrate.
Anisotropic etching is performed with an H solution to form such a multi-cantilever. Subsequently, a height of 5 mm is applied to the tip of the cantilever by an electron beam deposition method using carbon or the like.
A μm tunnel tip is provided. The elastic constant with respect to the deflection of the tip of the multi-cantilever thus manufactured is about 0.01 N / m for recording / reproducing, and 0.1 N / m for tilt correction.
m. Considering the warpage of each cantilever, the process error of the height of the tunnel tip, etc., the variation in the position of the tip of the tunnel tip in the height direction with respect to the Si substrate 110 of the multi-cantilever is about 1 μm. The waviness of the recording medium surface was about 1 μm.

Then, when the recording medium 109 is moved closer to the plurality of probe electrodes by the vertical coarse movement element 111, the recording medium 109 becomes one of the three probe electrodes for tilt correction located at the front of the plurality of probe electrodes. A tunnel current is detected from the probe electrode located at the closest position. Assuming that the probe electrode is p1, the tilt correction actuators s1, s2 and s3 corresponding to the respective tilt correction probe electrodes are driven, and the tunnel current detected from the probe electrode p1 is kept constant. A tunnel current is detected from another probe electrode. That is, the tilt correction actuator s2 positioned corresponding to a probe electrode other than the probe electrode p1 is extended so that a tunnel current is detected from the probe electrode p2. Next, the remaining tilt correction actuator s3 is extended so that a tunnel current is detected from the probe electrode p3. (Where p1, p2, p3 and s1, s2, s
The order of 3 is random. In this state, the inclination between the support and the recording medium is almost eliminated, and the distance between the recording / reproducing probe electrode and the recording medium is reduced, so that the recording medium is in a state suitable for recording / reproducing.

Next, a description will be given of a method of performing recording / reproducing using the recording / reproducing probe electrode approached to the recording medium by the above operation.

In this embodiment, a recording medium produced by the LB (Langmuir-Blodgett) method as described below was used.

After cleaning the optically polished glass substrate 112 with a neutral detergent and trichlene, a C
r was deposited to a thickness of 50 angstroms by a vacuum evaporation method, and Au was deposited to a thickness of 400 angstroms by the same method to form a base electrode 113. Next, squarylium-bis-6-octylazulene (hereinafter abbreviated as SOAZ)
Was dissolved at a concentration of 0.2 mg / ml in a water solution at 20 ° C. to form a monomolecular film on the water surface. The surface pressure of the monomolecular film waiting for evaporation of the solvent is 20 m
The electrode substrate was gently immersed at a speed of 5 mm / min so as to cross the water surface while maintaining this constant, and then pulled up to form a two-layer Y-type monomolecular film. With this operation, the recording medium 109 having the recording layer 114 is formed.

The recording medium 109 is supported on an XY drive mechanism 115.

FIG. 15 is a diagram showing an electrical connection configuration in the information recording / reproducing apparatus of the present invention. Each probe electrode is electrically connected as shown in FIG. SR, SW, and SE are switch elements connected to the reproduction bias application circuit 201, the recording pulse application circuit 202, and the erase pulse application circuit 203, respectively. Signal lines d, e, and f are control signals for each circuit.

Each switch element is a MOS switch manufactured on a silicon wafer by a conventionally known semiconductor technology.

An experiment of recording / reproducing / erasing using such an apparatus was performed as follows.

The multi-probe is positioned at a desired recording position by using the drive circuit 117 according to a command from the control processor 116.

The SR is always on except when recording or erasing, and a current of about 100 nA can be detected from each probe electrode in a state where the surfaces are aligned.

In this state, the SW is turned on (recording). S
W is specifically connected to a bias power supply of +6 V, and a pulse with a peak value of +6 V is applied between the probe electrode and the recording medium while the SW is on. When the probe electrode returns to the place where the pulse was applied again after waiting for the XY scanning, the detected probe current instantaneously becomes about 1 μm.
A. It is read that the detection current at the recording position has increased by about one digit (reproduction).

Further, when XY scanning is performed again and the tip of the probe electrode reaches the recording bit position, S is used instead of SR.
When a pulse having a peak value of -4 V is applied (erased) to the recording medium by turning E on, the probe current detected at that position thereafter returns to 100 nA. The above recording / reproducing / erasing can be stably repeated.

[0109]

[0110]

As described above, in the apparatus according to the present invention, even if the distance between each probe electrode and the medium surface is not controlled, the unevenness of the medium surface and the shape and size between the individual probe electrodes can be reduced. The relative distance between the tip of the probe electrode and the surface of the recording medium can be kept in a constant contact state regardless of the variation. Further, since control for each probe at the time of recording / reproducing as in the related art is not required, the scale of a control circuit and the like can be reduced, and as a result, power consumption and manufacturing cost can be reduced.

Further, since information can be recorded / reproduced in a state in which wear and destruction of the recording medium and the probe electrode are avoided, the life of the recording medium and the probe electrode can be extended.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of an apparatus according to a reference example 1 .

FIG. 2 is a cross-sectional view showing a configuration example of a probe electrode which is a main component of the device of Reference Example 1 .

FIG. 3 is a plan view of a substrate on which a plurality of probe electrodes are formed, which is used in the device of Reference Example 1 , as viewed from above.

FIG. 4 is a view showing a tilt mechanism of the device of Reference Example 1 .

FIG. 5 is a diagram showing a change in a tunnel current in the device of Reference Example 1 .

FIG. 6 is a diagram illustrating a plane correction in the X direction by a surface matching method in the apparatus of Reference Example 1 .

FIG. 7 is a diagram illustrating plane correction in the X direction in a surface matching method in the apparatus of Reference Example 1 .

FIG. 8 is a diagram showing a trajectory for aligning a surface of a recording medium with a scanning surface in the apparatus of Reference Example 1 .

9 is a diagram showing a control amount of the probe electrode in the vertical direction when the probe electrode is moved along the outer periphery of the recording area S shown in FIG. 8 in the device of Reference Example 1. FIG.

10 is a diagram showing a plurality of probe electrodes used in the equipment of Example 3.

FIG. 11 is a diagram illustrating plane correction in the X direction by a surface matching method in the apparatus of Reference Example 3 .

FIG. 12 is a diagram showing a plurality of probe electrodes used in the device of Reference Example 3 .

FIG. 13 is a diagram showing a plurality of probe electrodes used in the device of Reference Example 3 .

14 is a diagram showing the basic structure of the real施例of the present invention.

FIG. 15 is a diagram showing an electrical connection configuration in the device of the present invention.

FIG. 16 is a diagram showing a state of a plurality of probe electrode tips and a recording medium surface of the apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe electrode 2 Probe electrode attachment 3, 6 Tilt mechanism 4 Z direction fine movement / coarse movement mechanism 5, 301 Recording medium 7 XY direction fine movement / coarse movement mechanism 8 Interface 11, 102.302 Tunnel tip 12, 101 Cantilever 13, 17, 51, 304 substrate 14, 15 electrode 16 probe electrode 31 leaf spring 32, 33, 34 laminated piezoelectric element 35 rigid sphere 52, 113, 305 base electrode 53, 114 recording layer 81 write / read circuit 82 bias circuit 83, 90 tunnel current detection Device 84 Positioning circuit 85 Servo circuit 86 Z direction driving circuit 87 XY direction driving circuit 88 Position detecting circuit 89 Tilt mechanism driving circuit 103, 104, 105 Tilt correcting probe electrode 106, 107, 108 Tilt correcting drive element 110 Si substrate 111 Vertical Direction coarse movement element 112 glass substrate 115 XY drive mechanism 116 control processor 117 driving circuit 201 reproducing bias applying circuit 202 recording pulse applying circuit 203 erase pulse applying circuit 303 elastic body

Continuing on the front page (72) Inventor Toshimitsu Kawase 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Akihiko Yamano 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Kunihiro Sakai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takahiro Oguchi 3-30-2, Shimomaruko 3-chome, Ota-ku, Tokyo Canon Inc. (72) Invention Person Shunichi Murato 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-5-28545 (JP, A) JP-A 5-198019 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G11B 9/14

Claims (1)

(57) [Claims] 1. A recording medium, a plurality of probe electrodes arranged to face the recording medium, a support for supporting the plurality of probe electrodes, and means for correcting a tilt of the support with respect to the recording medium. Information processing means for relatively displacing the recording medium and the probe electrode in an in-plane direction parallel to the recording medium surface, and means for performing recording and reproduction in the presence of the probe electrode on the recording medium In the apparatus, the plurality of probe electrodes may use an elastic body having an elastic constant smaller than an elastic constant of the recording medium surface as a member constituting each probe electrode, and may be larger than an elastic constant of the recording medium surface. A plurality of elastic bodies each having an elastic constant are arranged at predetermined positions, and the correction means sets the large elastic constant to The information processing apparatus characterized by signal detected from a plurality of probe electrode using the elastic body for to correct the inclination of the recording medium and the support member so as to be constant.