JPH0371453A - Method and device for recording and reproducing - Google Patents

Abstract

PURPOSE:To obtain a recording and reproducing device that is superior in light resistance and stability by electrically recording and reproducing a recording medium provided with a recording layer having an electrical memory effect and an isolated microelectrode on this recording layer through the isolated microelectrode from a probe electrode. CONSTITUTION:The recording medium 1 having the recording layer 101 with the electrical memory effect and one or plural isolated microelectrode(s) 103 made of a conductive material on this layer is disposed between the probe electrode 102 and an opposite electrode 104. Then, in order to impress a voltage upon the recording medium 1 by the probe electrode 102 through the isolated microelectrode 103 on the recording layer 101, a distance Z of the electrode 102 is controlled by fine movement, and moreover a fine movement control mechanism 108 is designed to be capable of controlling fine movement in a plane X, Y direction as well. Consequently, the recording, reproducing and erasing of the isolated microelectrode in an optional position are carried out by the probe electrode 102. By this method, the recording and reproducing device that is superior in stability and light resistance is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a recording/reproducing method and a recording/reproducing device, and more particularly, to a recording/reproducing method and a recording/reproducing device, and more specifically, an electric memory effect is produced between at least a pair of electrodes, one of which is a probe electrode. Recording using a recording medium with a recording layer and minute isolated electrodes on the recording layer.
The present invention relates to a reproducing method and a recording/reproducing apparatus equipped with such a recording medium.

[Prior Art] In recent years, the use of memory devices has become a core part of the electronics industry, such as computers and related equipment, video discs, digital audio discs, etc.
Its development is also actively progressing. Generally speaking, the performance required of a memory device is (1) large memory capacity, (2) fast response speed for recording and playback, (3) excellent stability, (4) low error rate, and (5) consumption. Low electricity consumption (6) High productivity and low price, etc.

Until now, magnetic memory was made of magnetic materials or semiconductors,
Semiconductor memories have been the mainstream, but with advances in laser technology in recent years, inexpensive, high-density optical memory devices using organic thin films such as organic dyes and photopolymers have appeared.

[Problem to be solved by the invention] However, in the case of an optical memory that uses an organic thin film as a recording layer, it is very cheap because it uses an organic material.
In addition, since laser light is used for recording and reproduction, high density is achieved, but since the recording layer uses a material that reacts to light (particularly ultraviolet light), it has particularly poor light resistance and has problems with stability. Ta.

In addition, in order to improve light resistance, methods such as mixing ultraviolet absorbers into the organic material itself or covering the recording layer with ultraviolet absorbing film are used, but in this case, the reactivity to light conversely increases. As a result, there is a problem in that the recording sensitivity deteriorates and, for example, the error rate when writing and reproducing is performed with the same recording power as normal becomes large. That is, in the case of an optical memory that performs recording and reproduction using light, due to its characteristics, there are problems such as poor light resistance, that is, stability, or a poor error rate.

That is, an object of the present invention is to provide a recording/reproducing method and apparatus that solve the above-mentioned problems.

[Means and effects for solving the problems] The present invention is characterized by a recording layer having an electric memory effect, which has at least one probe electrode and a counter electrode disposed opposite to the probe electrode, and the recording layer. A recording medium having one or more minute isolated electrodes made of a conductive material on a layer is arranged between the probe electrode and the counter electrode.
It's on the playback device.

Furthermore, recording is performed by applying a voltage exceeding the threshold voltage that causes the electrical memory effect to the recording layer that has the electrical memory effect from the probe electrode through the micro isolated electrode, and performs recording at the threshold voltage that causes the electrical memory effect. The present invention is characterized by a recording/reproducing method in which reproduction is performed by applying a voltage that does not exceed .

That is, according to the present invention, a recording medium having a recording layer having an electric memory effect and a minute isolated electrode on the recording layer is provided with a method of electrically recording and reproducing from a probe electrode through the minute isolated electrode. , a recording/reproducing device with extremely excellent light resistance and stability, as the recording layer itself can use a material with light resistance, and the recording area is covered and protected by minute isolated electrodes. can be provided. In addition, in order to overcome the method of recording information on each small isolated electrode2, by arranging the small isolated electrodes regularly as desired in advance, it is also possible to perform tracking using the recorded bits, that is, the small isolated electrodes themselves. Become. This eliminates the need to form guide grooves, which simplifies the manufacturing process of the recording medium. Furthermore, by reducing the size of the minute isolated electrodes, it is possible to achieve a density equal to or higher than that of an optical disk.

Here, the recording medium used in the present invention is an organic cumulative film in which molecules having both a group having a π electron level and a group having only a σ electron level are stacked on an electrode, and a probe electrode is placed in a direction perpendicular to the film surface. By passing a current through a minute isolated electrode, it is possible to develop nonlinear current-voltage characteristics that are different from conventional ones.

Since most organic materials generally exhibit insulating or semi-insulating properties, the present invention can be applied to a wide variety of organic materials having a group having a π-electron level.

Examples of structures of dyes having a π-electron system suitable for the present invention include phthalocyanine, dyes having a porphyrin skeleton such as tetraphenylporphyrin, azulene dyes having squarylium groups and croconic methine groups as bonding chains, quinoline, benzothiazole, Cyanine-based similar dyes, such as benzoxazole, in which two nitrogen-containing heterocycles are bonded by a squarylium group and a croconic methine group, or cyanine dyes, fused polycyclic aromatics such as anthracene and pyrene, and aromatic and heterocyclic compounds and polymers of diacetylene groups, derivatives of tetracyanoquinodimethane or tetrathiafulvalene, analogs thereof, and charge transfer complexes thereof, and furthermore, fluoroethylene, trisbipyridine ruthenium complexes, etc. Examples include metal complex compounds.

Examples of polymeric materials suitable for the present invention include addition polymers such as polyacrylic acid derivatives, condensation polymers such as polyimide, ring-opening polymers such as nylon, and biopolymers such as bacteriorhodopsin.

Regarding the formation of the organic recording layer, it is possible to specifically apply vapor deposition methods, cluster ion beam methods, etc., but among known conventional techniques, LB is preferred due to its controllability, ease, and reproducibility.
The method is highly preferred.

According to this LB method, it is possible to easily form a monomolecular film of an organic compound having a hydrophobic site and a hydrophilic site in one molecule or a cumulative film thereof on a substrate, and the thickness is on the order of a molecule. Moreover, it is possible to stably supply a uniform and homogeneous ultra-thin organic film over a large area.

The LB method is a molecule with a structure that has a hydrophilic site and a hydrophobic site, and when the balance between the two (amphiphilic balance) is maintained appropriately, the molecule lowers the hydrophilic group on the water surface. This is a method of producing a monomolecular film or a cumulative film thereof by utilizing the fact that it becomes a monomolecular layer toward.

Examples of the group constituting the hydrophobic moiety include various hydrophobic groups such as generally widely known saturated and unsaturated hydrocarbon groups, fused polycyclic aromatic groups, and chain polycyclic phenyl groups. These each constitute a hydrophobic site singly or in combination. On the other hand, the most typical constituent elements of the wood-philic moiety are, for example, carboxyl groups, ester groups, acid a-do groups, i-do groups, hydroxyl groups, amino groups, (1, 2, tertiary and quaternary), and the like. These also constitute the hydrophilic portion of the above molecule either singly or in combination.

If these hydrophobic groups and hydrophilic groups are combined in a well-balanced manner, it is possible to form a monomolecular film on the water surface.
This is an extremely suitable material for the present invention.

Specific examples include the following molecules.

(Left below) Organic materials> [I] Dichronic methine dye [II] Squarylium dye [A compound in which the croconic methine group of the compound listed in II is replaced with a squarylium group having the following structure.

[III] Porphyrin dye compound Here, R8 corresponds to the group with the above-mentioned σ electron level, and is a long-chain alkyl group introduced to facilitate the formation of a monomolecular film on the water surface. The number of carbon atoms n is 5≦n≦
30 is preferred.

\ Oh.

-CHJI(C3)1y M = H2, Cu, Ni, A11-CR rare earth metal ion and r R” cnH2n+1 5≦n≦25M = 8
2. CLl, Ni, Zn, Al-Cl! and rare earth metal ion R= 0CH(COOH)CnLn+1 5 S
n525M = H, Cu, Ni, Zn,
R-CR and the rare earth metal ion R are introduced to facilitate the formation of a monomolecular film, and are not limited to the substituents listed here. Also, R1
-R4,R corresponds to the group having the above-mentioned σ electron level.

[IV] Condensed polycyclic aromatic compound ool [V] Diacetylene compound COW→CL)-Ca C-C cocoon c-+ C) It)-
XO≦n, jl≦20, but n+J! >10 X is a parent tree group, generally -COOH is used, but -O
H,-CONII2, etc. can also be used.

[■ko others Quinquethienyl 2) 4) Acrylic ester copolymer III.

5) polyvinyl acetate R.

6) vinyl acetate copolymer Organic polymer materials [ ■ ] addition polymer l) polyacrylic acid 2) polyacrylic acid ester II.

3) acrylic acid copolymer R.

[If] Condensation polymer 2) Polycarbonate R1 [III] Ring-opening polymer 1) Polyethylene oxide Here, R1 is a long-chain alkyl group introduced to make it easier to form a monomolecular film on the water surface; Carbon number n is 5≦n
≦30 is suitable.

Further, R5 is a short-chain alkyl group, and the number of carbon atoms n is 1≦n
≦4 is suitable. Degree of polymerization m is 100: S m '55
000 is preferred.

The compounds mentioned above as specific examples are only basic structures, and it goes without saying that various substituted products of these compounds are also suitable in the present invention9. Needless to say, any organic polymer material is suitable for the present invention. For example, biomaterials (e.g. batatteriorhodobuscin and cytochrome C) and synthetic polypeptides (PIILG), which are becoming increasingly researched by Kinhaya.
etc. can also be applied.

Such amphiphilic molecules form a monomolecular layer on the water surface with the parent group facing downward. At this time, the monomolecular layer on the water surface has the characteristics of a two-dimensional system, and when the molecules are sparsely dispersed, the two-dimensional ideal gas equation, π A=kT holds true, resulting in a "gas film". Here, k is Boltzmann's constant and T is absolute temperature. If A is made sufficiently small, the intermolecular interaction becomes stronger, resulting in a two-dimensional solid "condensation film (or solid film)." The condensed film can be transferred layer by layer onto the surface of arbitrary objects having various materials and shapes, such as glass and resin. Using this method, a monomolecular film or a cumulative film thereof can be formed and used as a recording layer.

As a specific manufacturing method, for example, the method shown below can be mentioned.

A desired organic compound is dissolved in a solvent such as chloroform, benzene, or acetonitrile. Next, using a suitable apparatus as shown in FIG. 7 of the accompanying drawings, this solution is spread on the aqueous phase 81 to form an organic compound in the form of a film.

Next, a partition plate (or float) 83 is provided to prevent the developed film 82 from freely diffusing and spreading too much on the aqueous phase 81.
The expanded area of the expanded membrane 82 is limited to control the aggregated state of the membrane material, and a surface pressure π proportional to the aggregated state is obtained. By moving the partition plate 83, the developed area can be reduced to control the aggregation state of the membrane material, and the surface pressure can be gradually increased to set the surface pressure π suitable for membrane production. While maintaining this surface pressure, the monomolecular film of the organic compound is transferred onto the substrate 84 by gently raising or lowering the clean substrate 84 vertically. Such a monomolecular film 91 is a film in which molecules are arranged in an orderly manner as schematically shown in FIG. 8a or 8b.

The monomolecular film 91 is manufactured as described above, and by repeating the above operations, a desired number of cumulative films can be formed. !
# To transfer the molecular film 91 onto the substrate 84, in addition to the above-mentioned vertical dipping method, methods such as a horizontal adhesion method and a rotating cylinder method can also be used. The horizontal deposition method is a method in which a monomolecular film is transferred by bringing the substrate into horizontal contact with the water surface, and the rotating cylinder method is a method in which a cylindrical substrate is rotated above the water surface to transfer the monomolecular film onto the substrate surface. It's a method.

In the vertical immersion method described above, when a substrate with a hydrophilic surface is lifted out of water in a direction across the water surface, a monomolecular film 91 of an organic compound with the hydrophilic portion 92 of the organic compound facing the substrate 84 is formed on the substrate 84. (Fig. 8b). When the substrate 84 is moved up and down as described above, the monomolecular films 91 are stacked one by one in each step, forming a cumulative film 94. Since the direction of the film-forming molecules is reversed between the pulling process and the dipping process, this method forms a Y-shaped film in which the hydrophobic parts 93a and 93b of the organic compound face each other between each layer of the monomolecular film (Fig. 9a). ). On the other hand, in the horizontal deposition method, a monomolecular film 91 with the hydrophobic portion 93 of the organic compound facing the substrate 84 side is used.
is formed on substrate 84 (FIG. 8a). In this method, even if the monomolecular film 91 is accumulated, the direction of the film-forming molecules does not change, and an X-shaped film is formed in which the hydrophobic parts 93a and 93b face the substrate 84 in all layers ( Figure 9b). On the contrary, the cumulative film 94 in which the hydrophilic parts 92a and 92b of all the layers face the substrate 84 side is called a Z-type film (No. 9C).
figure).

The method of transferring the monomolecular film 91 onto the substrate 84 is not limited to the above method, and when a large-area substrate is used, a method of extruding the substrate from a roll into an aqueous phase may also be adopted. Furthermore, the directions of the hydrophilic groups and hydrophobic groups described above toward the substrate are in principle, and can be changed by surface treatment of the substrate, etc.

As described above, an organic compound recording layer consisting of the monomolecular film 91 of an organic compound or its accumulation@94 is formed on the substrate 84.

In the present invention, the substrate 84 for supporting the thin film laminated with organic materials as described above may be made of any material such as metal, glass, ceramics, or plastic materials, and biomaterials with extremely low heat resistance may also be used. .

The substrate 84 as described above may have any shape, preferably a flat plate, but is not limited to a flat plate. That is, the film forming method (LB method) has the advantage that a film can be formed in accordance with the shape of the surface of the substrate, no matter what shape it is.

The material of the minute isolated electrodes of the recording medium used in the present invention may be any material as long as it has high conductivity, such as Au, Pt, etc.
, Ag, Pd, ACIn, Sn, Pb, W
There are many materials including metals such as metals, alloys thereof, graphite, silicides, and conductive oxides such as ITO, and their applications to the present invention can be considered. As a method for forming electrodes using such materials, conventionally known thin film forming techniques are sufficient. Further, the electrode shape of such a micro isolated electrode may be rectangular, large, etc., but any desired shape can be selected without being limited thereto. Furthermore, although the size of such a small isolated electrode can be various, it is preferable that it be as small as possible from the point of view of recording density.
For example, it is preferably 1,010,000p or less, preferably 1ILm" or less, which provides a high density comparable to or higher than that of an optical memory. Since the recording layer itself can be used as a molecular memory, the electrode size may be reduced to the size of a molecule. do not have.

On the other hand, the material of the counter electrode used in the present invention may be any material as long as it has high conductivity, such as Au.

Pt, Ag, Pd, A1. In, Sn, P
There are many materials that can be used in the present invention, including metals such as B and W, alloys thereof, graphite, silicide, and even conductive oxides such as ITO. Conventionally known thin film techniques are sufficient for forming electrodes using such materials. however,
The surface of the electrode material formed directly on the substrate is 1, B111.
During formation, it is desirable to use a conductive material that does not form an insulating oxide, such as a metal or an oxide conductor such as ITO.

Further, the material of the probe electrode may be any material as long as it exhibits conductivity and can apply a voltage to the recording layer through the minute isolated electrode of the recording medium. For example, Pt, Pt -
Examples include Ir, W, Au, Ag, and the like. The tip of the probe electrode needs to be as sharp as possible to match the size of the micro isolated electrode. In the present invention, a probe electrode is produced by controlling the shape of the tip of a needle-shaped conductive material using an electropolishing method, but the method and shape of the probe electrode are not limited thereto.

When a device with the MIM structure shown in FIG. 4 (shown in FIG. 4) is created using the materials and film-forming methods described above, a memory switching device exhibiting current-voltage characteristics as shown in FIGS. 5 and 6 can be obtained. It has already been found that the states 2-) (ON state and OFF state) each have memory properties. These memory switching characteristics range from several Å to several tens of Å.
However, the recording medium in the present invention preferably has a layer thickness in the range of IOλ to 1000 layers, most preferably 50 Å to 500 layers. . Further, when a cumulative film is formed by the LB method to form an organic insulating layer, the number of layers is preferably about 1 to 50. With the above-mentioned number of calendars and layer thicknesses, the preferred resistance value in terms of memory characteristics is desirably several MΩ or more in the OFF state.

In FIG. 4, 84 is a substrate, 41 is an Au electrode, 42 is an A2 electrode, and 43 is the aforementioned monomolecular cumulative film.

FIG. 1 is a block diagram showing a recording/reproducing apparatus of the present invention. In FIG. 1, 106 is a probe current amplifier;
07 is the probe electrode 10 on the recording layer 101? This is a servo circuit that controls a fine movement control mechanism 108 using a piezoelectric element so as to control the distance between the small isolated electrode 103 and the small isolated electrode 103 so that a voltage can be applied from the small isolated electrode 103. Reference numeral 109 denotes an electric current source for applying a pulse voltage for recording and erasing to the recording layer 101 between the probe electrode 102 and the counter electrode 104 through the minute isolated electrode 103.

110 is an XY scanning drive circuit for controlling the movement of the probe electrode 102 in the XY directions.

111 and 112 are probe electrodes 1c! 2
This is a coarse movement control mechanism for reducing the distance between the recording media 1 to some extent.

All of these devices are microcomputer 113
Centrally controlled by Further, 114 represents a display device.

[Example] Hereinafter, the present invention will be explained according to examples.

My husband, Naotoshi, used the recording/playback device shown in Figure 1. Probe electrode 1
As No. 02, a platinum/rhodium probe electrode prepared by an electric field polishing method was used. The distance (Z) of this probe electrode 102 is finely controlled by a piezoelectric element so that a voltage can be applied to the recording medium l through a minute isolated electrode 103 on the recording layer 101. Rough fine movement control mechanism 1
0B is designed to allow fine movement control in the in-plane (X, Y) directions while maintaining the above functions. Therefore, this lol
l. The motion control mechanism 108 allows the probe electrode 102 to record, reproduce, and erase minute isolated electrodes at arbitrary positions. In addition, the recording medium 1 is a high-precision XY stage 1
15 and can be moved to any position.

FIG. 2a shows the fine movement control mechanism 10B Hirobe electrode 102,
The fine movement control mechanism 108, which shows a schematic diagram of a recording medium, has a cylindrical piezoelectric element and electrodes for applying voltages for fine movement control in the X direction, Y direction, and Z direction.
As shown in the figure, scanning can be performed in the X direction by applying voltages to +X and -X.

Next, squarylium-bis-6-octyl azulene (hereinafter referred to as 5
The details of the recording/reproducing/erasing experiment when an LB film (8 layers) of OAZ (abbreviated as OAZ) was used as the recording layer and AP: was used as the minute isolated electrode 103 will be described in detail.

The recording medium 1 having the recording layer 101 in which 5OA28N was accumulated was placed on an XY stage, and the probe electrode 102 was first positioned visually and firmly fixed. next,
The position of the probe electrode 102 was adjusted by the fine movement control II mechanism 108 so that a voltage could be applied between the Au electrode 104 and the AF electrode 103 serving as a minute isolated electrode. The current value was measured by applying a reading voltage of 1.5 cm, which is a voltage that does not exceed the threshold voltage that causes an electrical memory effect, between the probe electrode 102 and the A2 electrode 103 and the AuN electrode 1.04. , several microns, A or less showed an OFF state. Threshold voltage vth-08 that causes the next ON state
After applying the triangular wave pulse voltage having the waveform shown in Figure 3, which is the above voltage, a voltage of 1.5 square meters was applied between the electrodes again and the current was measured, and a current of about 0.7 mA flowed. It showed that it was in the ON state. That is, O
N status was recorded.

Next, the threshold voltage V that changes from the ON state to the OFF state
After applying a triangular wave pulse voltage with a peak voltage of 5 cm and a pulse width of i usec, which is a voltage higher than th-arF, 1.5 V was applied again, and the current value at this time was several liters.
It was confirmed that the cell was in the OFF state at the bottom of the 8th floor.

Next, the position of the probe electrode 102 is adjusted by the fine movement control mechanism 108.
When we moved to a different micro-isolated electrode from the above and conducted the same recording, reproducing, and erasing experiments as before, we obtained exactly the same results, and the recording/reproducing device of the present invention It has been confirmed that it is valid.

After creating the ON state and Kano F state using the method described above,
The recording medium of the present invention was irradiated with light, and the recorded area was exposed to l. When a voltage of 5V was applied and regeneration was performed, the part that was in the ON state before the light irradiation had a current on the order of sub-111A flowing even after the light irradiation, and the part in the OFF state only had a current of less than a few caps. No change in recorded information due to light irradiation was observed, indicating that the film had excellent light resistance, that is, stability.

In addition, long-term storage of at least 3 months was possible in both the ON and OFF states.

The recording medium used in the above experiment was prepared as follows.

After cleaning the optically polished glass substrate (substrate 105) using a neutral detergent and Triclean, Cr was applied as an undercoat layer.
was deposited to a thickness of 50 mm using the vacuum evaporation (resistance heating) method.
Furthermore, 400 people evaporated 〇 using the same method, and the counter electrode (^
An electrode 104) was formed.

Next, go to SO8 at a concentration of 0.2mg/mi! The chloroform solution dissolved in 1 was spread on the water phase at 20°C to form a monomolecular film on the water surface. After waiting for the solvent to evaporate, the surface pressure of the monomolecular film was increased to 20111N101, and while keeping this constant, the electrode substrate was moved across the water surface at a speed of 5.
Gently crush it for 7 minutes, then pull it up again to form two layers of Y.
The accumulation of shaped monolayers was carried out. By repeating this operation an appropriate number of times, a cumulative film of eight layers was formed on the counter electrode.

Thereafter, a plurality of AN electrodes each having a thickness of 500 mm and a size of 50 μm square were formed as minute isolated electrodes on the recording layer made of the 5OAZ-LB film by a vacuum mask evaporation (resistance heating) method. A recording medium was produced.

Apart from this, the number of recording layers is 2°4, 12.
20, 30, 40, and 60 layers were prepared as type 7 recording media. Similar recording and playback experiments were conducted on this recording medium as well. Table 1 shows the evaluation results.
Shown below.

The evaluation is comprehensively judged based on the quality of recording and erasing properties after applying the recording write pulse and erasing voltage, as well as the ratio of current values in the recording state ε erasing state (ON10FF ratio) and stability. A rating of 01 indicates that the rating is good. A rating of 0 indicates that the rating is somewhat low compared to other items.

The thickness of each 5OAZ layer was determined by small-angle X-ray diffraction and was about 15.

An experiment was conducted in the same manner as in Example 1, except that polyimide was used instead of the 5OAZ recording layer used in Example 1. The results of recordability, 0N10FF ratio, and erasability are summarized in Table 1. Like 5OAZ, data signals can be recorded and reproduced, and data signals do not change due to light irradiation.
It had excellent light resistance.

Note that the method for forming the polyimide film is as follows.

Polyamic acid (molecular weight approximately 200,000) at a concentration of 1 x 10-3
% (g/g) of dimethylacetamide solution,
It was spread on an aqueous phase of pure water at a water temperature of 20°C to form a monomolecular film on the water surface. The surface pressure of this monomolecular film was increased to 25 mN/m, and while keeping this constant, the substrate was immersed and pulled up by moving it across the water surface at a rate of 5 mm/min, and the Y-shaped monomolecular film was accumulated. I did it. By repeating this operation, 12, 18.24.30.3B,
Seven types of cumulative films each having 42.60 layers were produced. Further, these films were heated at 300° C. for 10 minutes to form polyimide.

The thickness per polyimide 1r@ was determined to be about 4 by the ellipsometry method.

(Margin below) Table 1 44 Examples Experiments were carried out in the same manner as in Example 1 except that the t-butyl derivative of lutetium siphthalodianine [LuH(Pc) 21 was used instead of the 5OAZ recording layer used in Example 1. I did it. However, the number of recording layers is 2.
4.8, 12, 20, 30, 40, and 60 layers were tested.

The results of recording performance, 0N10FF ratio, erasability, and light resistance at this time were exactly the same as those for the 5OAZ recording film.
Similarly, data signals could be recorded and reproduced, and no change in data signals was observed due to light irradiation, indicating excellent light resistance.

Note that the cumulative conditions for the t-butyl derivative of LuH(Pc) z are as follows.

Solvent: Chloroform/trimethylbenzene/acetone (1/1/2) Concentration: 0.5 mg/mi) Water Phase: Pure water, water temperature 20°C Surface pressure: 20 mN/m, substrate vertical speed 3 mm/min Dish ±21 A recording medium was prepared using polyimide as the recording layer and the electrode materials shown in Table 2, and the same experiment as in Example 1 was conducted, and the results shown in Table 2 were obtained. As indicated by the 0 mark in the table, sufficient recording/reproducing characteristics and light resistance were obtained for all samples.

Note that all polyimide LB films have 24 layers. Further, the Au electrode was formed using a resistance heating method, the PT electrode was formed using an EB method, and the I-type electrode was formed using a sputtering method.

Table 2 In the examples described above, the LB method has been used to form the organic compound recording layer, but any film formation method that can produce an extremely thin and uniform film can be used other than the LB method. Examples include film forming methods such as MBE and CVD.

Regarding the formability of the counter electrode and minute isolated electrode, as already mentioned, any film forming method that can produce a uniform thin film can be used, and is not limited to the vacuum evaporation method.

Furthermore, the present invention does not limit the substrate material or its shape in any way.

[Effects of the Invention] As described above, according to the present invention, (1) it was possible to provide a recording/reproducing apparatus and a recording/reproducing method which are extremely superior in stability, particularly light resistance, compared to optical recording.

(1) Since one piece of information is recorded on each microscopic isolated electrode, by miniaturizing this electrode, it will be possible to provide recording/reproducing devices with higher density than optical memory devices in the future.

(2) Since the recording layer is formed by the accumulation of monomolecular films, it is possible to easily control the film thickness on the order of molecules (λ~several tens of molecules).

■ Since the recording layer can be thin, it is possible to provide a highly productive and inexpensive recording medium.

There are effects like this.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a recording/reproducing apparatus used in the present invention. FIGS. 2a and 2b are a schematic diagram and a scanning explanatory diagram of the It dynamic control mechanism. FIG. 3 shows the recording signal waveform. Figure 's4 is a schematic diagram of the configuration of the MIM element, and Figures 5 and 6 are characteristic diagrams showing the electrical characteristics obtained with the element of Figure 4. FIG. 7 is a schematic diagram of a cumulative film forming apparatus. Figures 8a and 8b are schematic diagrams of monolayers, with Nea
9b and 9c are schematic diagrams of the cumulative film. 1...Recording medium 41...＾ut8i42・
...＾l Electrode 43... Monomolecular cumulative film 81.
...Aqueous phase 82...Development membrane 83...Partition plate 84...Substrate 91...Monolayer film 92.92a, 92b-...Hydrophilic portions 93, 93a
, 93b -- Hydrophobic site 94 -- Cumulative membrane
101... Recording layer 102... Probe electrode 10
3... Micro isolated electrode 104... Counter electrode 10
5... Substrate 106... Probe current amplifier 107... Servo circuit 108... Fine movement control mechanism 109... Pulse power supply 110... XY scan drive circuit 111... Coarse movement mechanism 112... Coarse a drive circuit 113... microcomputer

Claims (10)

[Claims] (1) A recording layer having at least one probe electrode and a counter electrode disposed opposite to the probe electrode and having an electric memory effect, and one or more microisolated particles made of a conductive material on the recording layer. A recording/reproducing device characterized in that a recording medium having an electrode is disposed between the probe electrode and the counter electrode. (2) The recording/reproducing device according to claim 1, wherein the recording layer has a monomolecular film of an organic compound or a cumulative film formed by accumulating the monomolecular film. (3) The thickness of the monomolecular film or cumulative film is from several Å to several tens of angstroms.
3. The recording/reproducing apparatus according to claim 2, wherein the recording/reproducing apparatus has a range of 00 Å. (4) The thickness of the monomolecular film or cumulative film is 10 Å to 10 Å.
3. The recording/reproducing apparatus according to claim 2, wherein the recording/reproducing apparatus has a range of 00 Å. (5) The thickness of the monomolecular film or cumulative film is 50 Å to 50 Å.
3. The recording/reproducing apparatus according to claim 2, wherein the recording/reproducing apparatus is in a range of 0 Å. (6) The recording/reproducing apparatus according to claim 2, wherein the monomolecular film or the cumulative film is a film formed by an LB method. (7) The recording/reproducing device according to claim 2, wherein the organic compound has a group having a π electron level and a group having a σ electron level in the molecule. (8) The recording/reproducing apparatus according to claim 1, wherein the probe electrode has a scanning drive device in the direction of the surface of the recording layer. (9) The recording/reproducing apparatus according to claim 1, further comprising means for three-dimensionally controlling the relative position of the probe electrode and the recording medium. (10) Recording is performed by applying a voltage exceeding a threshold voltage that causes an electric memory effect to the recording layer having an electric memory effect from a probe electrode through a minute isolated electrode,
A recording/reproducing method characterized in that reproduction is performed by applying a voltage that does not exceed a threshold voltage that causes an electric memory effect and reading changes in the value of current flowing through the recording layer.