JPH117666A - Recording medium and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a high S/N ratio and high speed reproduction. SOLUTION: A recording medium is one having a recording layer with a smooth surface; a metallic layer 104 on the recording layer 103, which is formed on a first substrate 101 having a smooth surface through a peeling layer 102 with which the smooth substrate face is reproducible, is joined to a metallic layer 106 on a second substrate 105; with the first substrate 101 peeled from the peeling layer 102 or the recording layer boundary, the smooth shape of the first substrate face or the peeling layer 102 is transferred to the recording layer surface. The manufacture contains a process for forming the peeling layer 102 on the first substrate 101 having a smooth face, process for forming the recording layer 103 on the peeling layer 102, process for forming the metallic layer 104 on the recording layer 103, process for carrying out pressurizing after the metallic layer 104 is brought into contact with the metallic layer 106 formed on the second substrate 105, and a process for peeling the first substrate 101 from the peeling layer 102 or the recording layer boundary to transfer the first substrate face or the peeling layer shape to the surface of a recording medium 107.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a recording medium and a method for manufacturing the recording medium.

[0002]

2. Description of the Related Art The core of the electronics industry such as AV equipment is being actively developed. The performance required for the memory material varies depending on the application, but in general, (1) high density and large recording capacity (2) fast response time for recording and reproduction (3) low power consumption (4) productivity Are high and prices are low. Until now, semiconductor memories and magnetic memories using magnetic materials and semiconductors as the main material were mainly used.However, with the remarkable progress of laser technology in recent years, inexpensive optical memories using organic thin films such as organic dyes and photopolymers High-density recording media have appeared.

On the other hand, recently, a scanning tunneling microscope (hereinafter abbreviated as STM) capable of directly observing the electronic structure of surface atoms of a conductor has been developed [G. Binnig et al. ,
Phys. Rev .. Lett. , 49, 57 (198
2)], it is possible to measure a real space image with high resolution irrespective of whether it is single crystal or amorphous, and has the advantage that it can be observed with low power without damaging the sample by electric current. It operates and can be used for various materials, so that a wide range of applications can be expected. The STM utilizes the fact that a tunnel current flows when a voltage is applied between a metal probe and a conductive material to approach a distance of about 1 nm. This current is very sensitive to changes in the distance between them. By scanning the probe so as to keep the tunnel current constant, it is possible to read various kinds of information on all electron clouds in the real space. At this time, the resolution in the in-plane direction is about 0.1 nm. Therefore, if the principle of the STM is applied, it becomes possible to perform ultra-high-density recording / reproduction sufficiently in the atomic order (sub-nanometer). For example, JP-A-61-80
In the recording / reproducing apparatus disclosed in Japanese Patent Publication No. 536, the atomic particles adsorbed on the medium surface are removed by an electron beam or the like, writing is performed, and this data is reproduced by STM. As a recording layer, a method has been proposed in which recording and reproduction are performed by STM using a material having a memory effect on the switching characteristics of voltage and current, for example, a thin film layer of a π-electron organic compound or chalcogen compound ( JP-A-63-
161552, JP-A-63-161553). According to this method, the recording bit size is set to 10 nm.
If this is the case, large-capacity recording and reproduction as high as 10 12 bits / cm 2 can be achieved.

FIG. 2 shows a configuration example of an information processing apparatus to which the STM technology is applied. Hereinafter, description will be made with reference to the drawings. 11
Denotes a substrate, 12 denotes a metal electrode layer, and 13 denotes a recording layer. 2
01 is an XY stage, 202 is a probe, 203 is a support for the probe, 204 is a linear actuator for driving the probe in the Z direction, and 207 is a pulse voltage circuit. An amplifier 301 detects a tunnel current flowing from the probe 202 to the electrode layer 12 via the recording layer 13. 302 is a logarithmic compressor for converting a change in tunnel current into a value proportional to the gap distance between the probe 202 and the recording layer 13, and 303 is a recording layer 1
3 is a low-pass filter for extracting surface unevenness components. Reference numeral 304 denotes the reference voltage Vref and the low-pass filter 3
03, an error amplifier for detecting an error with respect to the output of
This is a driver for driving the shaft linear actuator 204. A drive circuit 306 controls the position of the XY stage 201. 307 is a high-pass filter for separating data components.

FIG. 5 shows a cross section of a conventional recording medium and a probe 20.
2 is shown. 401 is a data bid recorded on the recording layer 13, and 402 is a crystal grain formed when the electrode layer 12 is formed on the substrate 11. The size of the crystal grains 402 is about 30 to 50 nm when a normal vacuum deposition method, a sputtering method, or the like is used as a method for manufacturing the electrode layer 12. The gap between the probe 202 and the recording layer 13 can be kept constant by the circuit configuration shown in FIG. That is, a tunnel current flowing between the probe 202 and the recording layer 13 is detected, and the logarithmic compressor 302,
After passing through the low-pass filter 303, this value is compared with the reference voltage, and the Z-axis linear actuator 204 that supports the probe 202 is controlled so that the comparison value approaches zero, so that the signal is recorded with the probe 202. The gap of the layer 13 can be made constant.

Further, by driving the XY stage 201, the probe 202 traces the surface of the recording medium.
The data of the recording layer 13 can be detected by separating the high frequency components of the signal at the point a in FIG. A at this time
FIG. 4 shows the signal intensity spectrum with respect to the frequency of the signal at the point.

The signal of the frequency component equal to or lower than f0 is due to the gradual undulation of the medium due to the warpage or distortion of the substrate 11. The signal centered at f1 is due to irregularities on the surface of the recording layer 13, and is mainly due to crystal grains generated during the formation of the electrode material. f2 is a carrier component of the recording data and is 4
03 is a data signal band. f3 is a signal component generated from the arrangement of atoms and molecules in the recording layer 13. fc is a cutoff frequency of the high-pass filter 307, and fT is a tracking signal component detected when a tracking groove is formed on the recording layer.

[0008]

When the recording medium shown in the above-mentioned conventional example is used, there are the following problems. To perform high-density recording utilizing the high resolution characteristic of the STM, the data signal band 403 must be set to f1.
And f3. In this case, a high-pass filter 307 having a cutoff frequency fc is used to separate data components. However, the base of the signal component of f1 overlaps with the data signal band 403. This is because the signal component of f1 is caused by crystal grains of the electrode layer 12, and the data recording size and the bit interval are close to 1 to 10 nm with respect to 30 to 50 nm of the crystal grains. For this reason, the S / N ratio of data reproduction is reduced, and the error rate of read data is significantly increased.

Accordingly, the present invention solves the above-mentioned problems of the prior art, and provides a recording medium having a high S / N ratio and enabling high-speed reproduction, and a method of manufacturing the recording medium. It is an object.

[0010]

According to the present invention, a recording medium and a method of manufacturing the recording medium are configured as follows to solve the above-mentioned problems. That is, the recording medium of the present invention is a recording medium having a recording layer having a smooth surface, wherein the recording layer having the smooth surface is formed on the first substrate having the smooth substrate surface. A metal layer on the recording layer formed via a reproducible release layer,
The metal layers on the second substrate are bonded to each other, and the first substrate is separated from the release layer or the interface of the recording layer to transfer a smooth shape of the first substrate surface or the release layer to the surface of the recording layer. It is characterized by being formed. Further, the recording medium of the present invention is characterized in that the release layer is an organic compound formed by a Langmuir-Blodgett method. Further, the recording medium of the present invention is characterized in that the recording layer is made of a chalcogenide thin film material. Further, in the recording medium of the present invention, the metal layer on the first substrate may be
It is characterized in that it has a noble metal single layer or a multilayer structure made of a noble metal and other metals. Further, in the recording medium of the present invention, the noble metal is preferably Au, Ag, Cu, Pt, or Pt.
d, Ir, Rh, or Ru, or an alloy containing them. Further, the recording medium of the present invention is characterized in that the metal layer on the second substrate has a single-layer or multilayer structure. Further, in the recording medium of the present invention, the metal layer formed on the second substrate may be made of Au, A
g, Cu, Pt, Pd, Ir, Rh, Ru, or Al, or an alloy containing them. Further, the recording medium of the present invention is characterized in that the recording medium has a smooth surface having a surface roughness of 0.5 nm or less and 1 μm square or more. The method for producing a recording medium according to the present invention is a method for producing a recording medium having a recording layer with a smooth surface. 1. forming a release layer on a first substrate having a smooth surface; 2. forming a recording layer on the release layer; 3. forming a metal layer on the recording layer; 4. a step of performing a pressure treatment after bringing the metal layer into contact with the metal layer formed on the second substrate; Separating the first substrate from the release layer or the interface of the recording layer to transfer the shape of the first substrate or the release layer to the surface of the recording medium. In the method for manufacturing a recording medium according to the present invention, the release layer is an organic compound formed by a Langmuir-Blodgett method. In the method for manufacturing a recording medium according to the present invention, the recording layer is formed of a chalcogenide thin film. Further, the method of manufacturing a recording medium according to the present invention is characterized in that the metal layer on the first substrate has a single layer of a noble metal or a multi-layer structure made of a noble metal and another metal. Further, in the method for manufacturing a recording medium of the present invention, the noble metal may be Au, Ag, Cu, Pt, Pd, Ir, R
h or Ru, or an alloy containing them. Further, the method of manufacturing a recording medium according to the present invention is characterized in that the metal layer on the second substrate has a single-layer or multilayer structure. Further, in the method for manufacturing a recording medium according to the present invention, the metal layer formed on the second substrate may include:
Au, Ag, Cu, Pt, Pd, Ir, Rh, Ru, A
1 or an alloy containing them. Further, the method of manufacturing a recording medium of the present invention,
In the step of performing the pressure treatment, a heat treatment is performed after the pressure treatment. Further, the method of manufacturing a recording medium according to the present invention is characterized in that in the step of performing the pressure treatment, the pressure treatment and the heat treatment are performed simultaneously. Also,
The method for manufacturing a recording medium according to the present invention is characterized in that the recording medium has a smooth surface having a surface roughness of 0.5 nm or less and 1 μm square or more.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention can provide a recording medium having a smooth surface with the above-described configuration, thereby making it possible to make full use of the function of an information processing apparatus applying the principle of STM. . Hereinafter, the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing each step of the method for manufacturing a recording medium according to the present invention. FIG. 1- (a)
First, a first substrate 101 is prepared. The substrate preferably has a smooth surface having a surface roughness of 0.5 nm or less, preferably 1 μm.
It is necessary to have m square or more. Surface irregularities can be measured by an atomic force microscope (hereinafter, referred to as AFM). By using the AFM, the surface shape of a sample can be measured with an atomic order resolution regardless of the presence or absence of conductivity of the sample. The present inventor evaluated the surface roughness of various materials using AFM, and found that the following materials, particularly smooth materials, were suitable for the first substrate 101 in the present invention. (1) Cleavage surface of crystal: The cleavage surface of the crystal can easily obtain an extremely smooth surface.
O, TiC, Si, mica, HOPG, and the like. (2) molten glass surface: for example, float glass,
# 7059 fusion fused quartz. (3) Others: An extremely smooth surface can be obtained even with a Si thermal oxide film on a sufficiently smooth Si wafer surface.

Next, as shown in FIG. 1B, a release layer 102 is formed on the first substrate 101. As the release layer 102, for example, an organic monomolecular film or its cumulative film is
It can be formed by the B (Langmuir-Blodgett) method. The organic monomolecular film of these molecules formed by the LB method, the accumulated film thereof, or the polymer film thereof faithfully reproduces the unevenness of the substrate, so that the first substrate 101 does not lose its smoothness. A smooth surface can be obtained on 101. Next, a recording layer 103 is formed on the release layer 102 as shown in FIG. As the recording layer 103, for example, a chalcogenide thin film can be formed by a sputter deposition method or the like. Chalcogenide thin films have already been put to practical use as phase-change optical disks. In a phase change optical disk, recording is performed by causing a reversible phase change according to the laser beam irradiation conditions on the chalcogenide thin film, and reproduction is performed by reading an optical change caused by the phase change. On the other hand, it is known that the conductivity of a chalcogenide thin film changes when a voltage is applied (Japanese Patent Application Laid-Open No. 63-222348).

Next, as shown in FIG. 1D, a metal layer 104 is formed on the recording layer 103. The metal layer 104 has high conductivity, for example, Pt, Pd, I
Precious metals such as r, Rh, Ru, and Au or alloys thereof are preferably used. In particular, the metal in contact with the recording layer 104 needs to be a metal on which an oxide film is hardly generated. W,
Some of Ta, Ti, Cr, Al, Cu, Ag, and the like are inexpensive and have a small coefficient of thermal expansion, so that they can be used as a laminated film on a metal on which an oxide film is hardly generated. further,
Preferably, a layer mainly composed of Au is formed on the outermost surface.
Since Au is soft and has a low melting point, it can be joined at a lower pressure and a lower temperature. Therefore, it can be preferably used as the outermost surface. As a method of forming a thin film using such a material, a conventionally known thin film forming technique is sufficient. Next, as shown in FIG. 1E, a metal layer 106 is formed on the second substrate 105. Examples of the material of the metal layer 106 include noble metals such as Pt, Pd, Ir, Rh, Ru, and Au, alloys thereof, and W, Ta, Ti, Cr, and A.
It may be a laminated film of l, Cu, Ag, or the like. Particularly, a layer mainly composed of Au is preferably formed on the outermost surface.

Next, as shown in FIG. 1- (f), the metal layer surfaces 104 of the first substrate 101 and the second substrate 105 are separated from each other.
106 are brought into contact and pressure is applied. The pressure at this time is not particularly limited, but is about several kg to several tens kg / cm ² .
When heat treatment is used, bonding can be performed at a lower pressure. The temperature in this case depends on the pressure, but is usually 1000 ° C. or less. The heat treatment may be performed separately from the pressure treatment, but is preferably performed simultaneously. Next, as shown in FIG. 1G, the first substrate 101 is separated. Peeling occurs at the interface between the peeling layer 102 and the recording layer 103. In this case, if the release layer 102 remains on the recording layer, it can be easily removed by oxygen plasma treatment. Thereby, the recording medium 107 can be obtained. The smoothness of the recording layer surface is equal to the smoothness of the first substrate 101, and has a smooth surface with a surface roughness of 0.5 nm or less and a square of 1 μm or more.

FIG. 5 is a cross-sectional view of the medium and the probe when the information processing apparatus shown in FIG. 2 is used as the recording medium 107 according to the present invention.
(A). FIG. 5B shows the frequency spectrum of the signal at points a and b in FIG. The signal of the frequency component equal to or lower than f0 is due to the gradual undulation of the medium due to the warpage or distortion of the recording medium 107. f2 is a carrier component of the recording data, and 403 is a data signal band. f3 is a signal component generated from the arrangement of atoms and molecules in the recording layer 103. fc is a cutoff frequency of the high-pass filter 307, and fT is a signal component when a tracking groove is formed on the recording layer. The signal centered at f1 is obtained by transferring a slight unevenness of the first substrate 101, and the unevenness of the data must be smaller than the recording signal f2, the cutoff frequency fc of the high-pass filter 307, and the tracking signal fT. Therefore, f1 needs to be as small as possible. In particular, in a terabit-class ultra-large-capacity memory, it is necessary to scan an STM probe at a higher scanning speed. However, when the scanning speed is increased, f
Since 1 also increases to approach fc, high-speed scanning is hindered as a result. Therefore, it is extremely important to obtain a substrate with high smoothness that can reduce the f1 component.

As described above, the following functions and effects can be obtained. 1. With a recording medium having a smooth surface, the signal component f1 caused by the roughness of the recording layer surface can be extremely reduced.
Even at a higher scanning speed, the f1 component can be kept sufficiently lower than the fc component. 2. Since the recording medium is composed of the inorganic material layer and the metal layer, an electrode substrate having high heat resistance can be formed. 3. Since the recording layer and the metal layer (electrode layer) can be transferred collectively, the manufacturing process becomes extremely simple. 4. Since the metal layer is used as the bonding layer, the adhesive does not protrude to a portion other than the desired bonding surface as compared with the case where a coating type organic bonding layer or the like is used. 5. Since a metal layer is used as the bonding layer, it is easier to control the height of the recording layer surface from the substrate surface holding the metal layer and to make the surfaces parallel, etc., as compared to the case where a coating type organic adhesive layer is used. be able to. 6. A smooth recording layer can be formed on any substrate material as long as it can form a metal layer.

[0017]

The following is a description of the method for smoothing a gold crystal surface of the present invention.
This will be described in detail with reference to examples. Embodiment 1 Embodiment 1 of the present invention will be described with reference to FIG. First, as shown in FIG. 1A, a smoothed Si (111) wafer was prepared and used as a first substrate 101. In the smoothing treatment, first, the film was immersed in a boiling sulfuric acid: hydrogen peroxide solution = 4: 1 solution for 5 minutes, and then immersed in 5% hydrofluoric acid for 1 minute. Furthermore, hydrofluoric acid: ammonium fluoride = 3:50
Was immersed in the solution for 10 minutes, then washed with water and dried. next,
As shown in FIG. 1- (b), a polyamic acid alkylamine salt accumulation film is formed on a first substrate 101 as disclosed in JP-A-63-161.
It was formed by the method (LB method) disclosed in JP-A-552. This cumulative film was baked at 250 ° C. for 30 minutes to be polyimide to form a release layer 102. The surface roughness of the release layer 102 thus obtained was measured by AFM and found to be 0.3 nm or less in a square of 1 μm. Next, as shown in FIG. 1C, a chalcogenide thin film (GeS) is formed on the release layer 102 by a binary sputter deposition method.
b ₂ Te ₄ ) was formed to a thickness of 20 nm to form the recording layer 103. Next, as shown in FIG.
An alloy layer made of Pt and Au was formed to a thickness of 300 nm and Au was formed to a thickness of 50 nm as the metal layer 104 on the metal layer 104.
Next, as shown in FIG. 1E, a Cr film having a thickness of 5 is formed as a metal layer 106 on a second substrate 105 made of a Si wafer.
nm and Au were formed to a thickness of 100 nm. Next, FIG.
As shown in (f), after the metal layer surfaces 104 and 106 of the first substrate 101 and the second substrate 105 were put together, pressure was applied so that both substrates were pressed against each other. The pressure is 5kg /
cm ² . Next, both substrates were heated at 200 ° C.
And held for 10 seconds before cooling to room temperature. Next, as shown in FIG. 1- (g), the recording medium 107 was peeled off from the interface between the release layer 102 and the recording layer 103 to obtain a recording medium 107 having a smooth surface. Recording layer 1 thus obtained
When the surface roughness of No. 03 was measured by AFM, it was 0.3 nm or less in 1 μm square.

Next, a recording / reproducing experiment was performed. Probe 202
Used was made of Pt / Rh. The distance (Z) of the probe 202 is finely controlled by a piezoelectric element so that the current is kept constant by controlling the distance (Z) to the surface of the recording layer 103. Further, the linear actuators 204, 205, and 206 are designed so that fine movement control can be performed in the in-plane (X, Y) direction while keeping the distance Z constant. The recording medium 108 described above was placed on the XY stage. Next, the probe 202 and the electrode layer 10 of the recording medium
A voltage of +1.0 V was applied during the period 2, and the distance Z between the probe 202 and the surface of the recording layer 103 was adjusted while monitoring the current. At this time, the distance Z between the probe 202 and the surface of the recording layer 103
Is set so that 10 ⁻¹⁰ ≧ Ip ≧ 10 ⁻¹¹ . Next, information was continuously recorded at a pitch of 20 nm while scanning the recording layer 103 with the probe 202. For recording, a rectangular pulse voltage was applied with the probe being + and the electrode layer being-. Then, when the recorded bit was scanned again, it was confirmed that a current of about 10 nA flowed on the bit. Next, the error rate of the read data was examined with the reading speed kept constant. As a result, the error rate was 10 ^{-1 in the related art} , but was significantly reduced to 10 ^{-7 in the} present embodiment.

Second Embodiment A second embodiment of the present invention will be described with reference to FIG. First, as shown in FIG. 1A, float glass having sufficiently high smoothness was used as the first substrate 101. Next, as shown in FIG.
A polyamic acid alkylamine salt cumulative film was formed thereon by the LB method. This cumulative film was baked at 250 ° C. for 30 minutes to be polyimide to form a release layer 102. The surface roughness of the release layer 102 thus obtained was measured by AFM and found to be 0.3 nm or less in a square of 1 μm. Next, as shown in FIG. 1- (c), a chalcogenide thin film (GeSb ₂ Te ₄ ) having a thickness of 20 nm was formed on the release layer 102 by a binary sputter deposition method to form a recording layer 10.
3 was formed. Next, as shown in FIG. 1D, an alloy layer of Pd and Au was formed on the recording layer 103 as the metal layer 104 to a thickness of 300 nm, and further, Au was formed to a thickness of 50 nm. Next, as shown in FIG. 1E, Cr was formed to a thickness of 5 nm and Au was formed to a thickness of 100 nm as a metal layer 106 on a second substrate 105 made of a Si wafer. Next, FIG.
As shown in (f), after the metal layer surfaces 104 and 106 of the first substrate 101 and the second substrate 105 are aligned,
Pressure was applied so that both substrates were pressed against each other. Pressure is 10k
g / cm ² . Next, as shown in FIG. 1- (g),
Peeling off from the interface between the release layer 102 and the recording layer 103,
A recording medium 107 having a smooth surface was obtained. The surface roughness of the recording layer thus obtained was measured by AFM and found to be 0.3 nm or less in a square of 1 μm. Then, in the same manner as in Example 1, subjected to experiments of the recording and reproducing, the error rate of the read data, were examined by the reading speed constant, in the conventional that which was at 10 ^1, in this embodiment 10 It became possible to remarkably reduce it to ^-7 .

Third Embodiment A third embodiment of the present invention will be described. First, a Si wafer smoothed in the same manner as in Example 1 was used as a first substrate 101, and a polyamic acid alkylamine salt cumulative film was formed on the first substrate 101 by the LB method. This accumulation film was made into a polyimide by a chemical treatment to form a release layer 102. When the surface roughness of the release layer 102 thus obtained was measured by AFM, 1 μm was obtained.
It was 0.3 nm or less in m square. Next, a chalcogenide thin film (Ge ₂ Sb ₂ Te ₅ ) having a thickness of 20 nm was formed on the release layer 102 by a binary sputter deposition method to form the recording layer 103. Next, Pt was formed to a thickness of 500 nm and Al was formed to a thickness of 100 nm as the metal layer 104 on the recording layer 103. Next, a second silicon wafer
5n of Cr as the metal layer 105 on the substrate 105 of FIG.
m and Al were deposited to a thickness of 100 nm. Next, the metal layer surfaces 104 of the first substrate 101 and the second substrate 105 are separated from each other.
After the setting of No. 06, pressure was applied so that both substrates were pressed against each other. The pressure was 10 kg / cm ² . 300 ° C after pressurization
For 1 minute. Next, the recording medium 1 having a smooth surface is peeled off from the interface between the release layer 102 and the recording layer 103.
07 was obtained. The surface roughness of the recording layer thus obtained was measured by AFM.
nm or less. Then, in the same manner as in Example 1, subjected to experiments of the recording and reproducing, the error rate of the read data, were examined by the reading speed constant, in the conventional that was 10 ^-1, in this example 10 It became possible to remarkably reduce it to ^-7 .

[0021]

As described above, according to the recording medium and the method of manufacturing the recording medium of the present invention, the signal component f1 caused by the roughness of the recording layer surface can be made extremely small, so that the f1 component can be obtained even at a higher scanning speed. Can be kept sufficiently lower than the fc component. Further, according to the present invention, since the recording medium is composed of the inorganic material layer and the metal layer, a substrate of the recording medium having high heat resistance can be formed. Also,
According to the method for producing a recording medium of the present invention, the recording layer and the metal layer constituting the electrode layer can be transferred collectively, so that the production process is simplified. In addition, according to the method for manufacturing a recording medium of the present invention, since a metal layer is used as a bonding layer, compared to a case where a coating-type organic adhesive layer or the like is used, the protrusion of the adhesive to a portion other than a desired bonding surface is eliminated. be able to. Further, according to the method for manufacturing a recording medium of the present invention, since the metal layer is used as the bonding layer, the surface of the recording layer from the substrate surface holding the metal layer is compared with the case where a coating type organic adhesive layer or the like is used. It is possible to easily perform height control, parallel alignment of surfaces, and the like. Further, according to the recording medium manufacturing method of the present invention, a smooth recording layer can be formed on any substrate material as long as the material can form a metal layer.

[Brief description of the drawings]

FIG. 1 is a diagram showing a manufacturing method of the present invention.

FIG. 2 is a diagram showing an information processing apparatus to which STM is applied.

FIG. 3 is a schematic sectional view of a conventional recording medium.

FIG. 4 is a diagram of a frequency spectrum of a conventional reproduced signal.

FIG. 5 is a schematic cross-sectional view of a recording medium of the present invention and a diagram of a frequency spectrum of a reproduced signal of the present invention.

[Explanation of symbols]

 11: substrate 12: metal electrode layer 13: recording layer 101: first substrate 102: release layer 103: recording layer 104: metal layer 105: second substrate 106: metal layer 107: recording medium 201: XY stage 202 : Probe 203: probe support 204, 205, 206: linear actuator 207: pulse voltage circuit 301: amplifier 302: logarithmic compressor 303: low-pass filter 304: error amplifier 305: driver 306: drive circuit 307: High-pass filter 401: data bit 402: crystal grain 403: data signal band

Claims (18)

[Claims] 1. A recording medium having a recording layer having a smooth surface, wherein the recording layer having a smooth surface is formed on a first substrate having a smooth substrate surface by peeling capable of reproducing the smooth substrate surface. A metal layer on the recording layer formed via a layer and a metal layer on a second substrate are joined to each other, and the first substrate is separated from the release layer or the interface of the recording layer to form a first substrate surface. Alternatively, a recording medium formed by transferring a smooth shape of the release layer to the surface of the recording layer. 2. The recording medium according to claim 1, wherein the release layer is an organic compound formed by a Langmuir-Blodgett method. 3. The recording medium according to claim 1, wherein said recording layer is formed of a chalcogenide thin film. 4. The method according to claim 1, wherein the metal layer on the first substrate has a single layer of a noble metal or a multilayer structure made of a noble metal and another metal. recoding media. 5. The method according to claim 1, wherein the noble metal is Au, Ag, Cu, Pt,
The recording medium according to claim 4, wherein the recording medium is any one of Pd, Ir, Rh, and Ru, or an alloy containing them. 6. The recording medium according to claim 1, wherein the metal layer on the second substrate has a single layer or a multilayer structure. 7. The method according to claim 7, wherein the metal layer formed on the second substrate is A
u, Ag, Cu, Pt, Pd, Ir, Rh, Ru, Al
7. The recording medium according to claim 6, wherein the recording medium is an alloy containing any of the above. 8. The recording medium has a surface roughness of 0.5 n.
The recording medium according to any one of claims 1 to 7, wherein the recording medium has a smooth surface of 1 m or more having a smooth surface of m or less. 9. A method for producing a recording medium having a recording layer with a smooth surface, comprising: 1. forming a release layer on a first substrate having a smooth surface; 2. forming a recording layer on the release layer; 3. forming a metal layer on the recording layer; 4. a step of performing a pressure treatment after bringing the metal layer into contact with the metal layer formed on the second substrate; Separating the first substrate from the release layer or the interface of the recording layer and transferring the shape of the first substrate or the release layer to the surface of the recording medium. 10. The method according to claim 9, wherein the release layer is an organic compound formed by a Langmuir-Blodgett method. 11. The method according to claim 9, wherein said recording layer is made of a chalcogenide thin film. 12. The method according to claim 9, wherein the metal layer on the first substrate has a single layer of a noble metal or a multilayer structure made of a noble metal and another metal. Manufacturing method of recording medium. 13. The method according to claim 13, wherein the noble metal is Au, Ag, Cu, P
13. The method for manufacturing a recording medium according to claim 12, wherein the recording medium is any one of t, Pd, Ir, Rh, and Ru, or an alloy containing them. 14. The metal layer on the second substrate has a single-layer or multilayer structure.
The method for producing a recording medium according to any one of the above items. 15. The metal layer formed on the second substrate,
Au, Ag, Cu, Pt, Pd, Ir, Rh, Ru, A
15. The method for manufacturing a recording medium according to claim 14, wherein the recording medium is any one of (1) and (1) or an alloy containing them. 16. The method for manufacturing a recording medium according to claim 9, wherein in the step of performing the pressure treatment, a heat treatment is performed after the pressure treatment. 17. The method according to claim 9, wherein in the step of performing the pressure treatment, the pressure treatment and the heat treatment are performed simultaneously.
A method for manufacturing the recording medium according to claim 15. 18. The recording medium has a surface roughness of 0.5
The method for manufacturing a recording medium according to any one of claims 9 to 17, wherein the recording medium has a smooth surface of 1 nm or more having a smooth surface of 1 nm or less.