JPS58118292A - Optical recording medium - Google Patents

Abstract

PURPOSE:To provide an optical recording medium with a better recording sensitivity by providing a low-melting-point metal thin film on which a recording part high in the rate of reflecting to laser beam is to be formed with the irradiation of the laser beam. CONSTITUTION:A thin film 2 of very microscopic metallic or semimetallic particles more than 60% in the rate of absorbing laser beam ranging 600-1,000nm with numerous clearances whose melting point is too high to be melted with the irradiation of the laser beam is laminated on a metallic or semi-metallic thin film 4 whose melting point is so low to be melted with the irradiation of the laser beam. The low-melting-point metallic or semi-metallic thin film 2 adjacent to the thin film 4 made of very microscopic particles is melted with the irradiation of the laser beam to form a recording part by the reflection of light due to the penetration of the metal. Metal composing the low-melting-point metallic or semi-metallic thin film includes In, Sn, Pb, Zn, Bi, Sb, Te and Se.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new type of optical recording having a thin film of a low melting point metal or metalloid, in which a recording portion with a high reflectance to laser light is formed by irradiation of a portion of the laser beam. Regarding the medium.

Optical recording media are also called "optical desks." This K is
Broadly speaking, first, recording is performed by making a large number of minute holes (Cbit) in a thin film of a metal or semimetal with a low melting point using a laser beam, and then detecting the presence of holes in a part of the film using a laser beam. The second method is to record by printing a large number of minute irregularities on the recording layer made of a suitable material, and detect the presence of irregularities by the reflection of a part of the laser beam. There are two known methods:
Each has its advantages and disadvantages (Television Science Society★ Magazine, Vol. 33, No. 9 (+979), pp. 10-16).

In the case of an optical recording medium in which recording is performed using a hole-shaped fi, T-t isi is placed on a PMM-based plastic or glass plate.

A thin film of a metal or semimetal with a low melting point such as In, 8n, 8e, Zn, Pb, 119-mu, T@-fle, etc. is formed as a recording layer (by N deposition, etc.)
It is known that the force O%O becomes. In this method, the recording is done by melting a part of the thin film with laser beams or by irradiating it with a laser beam.
This is done by engraving a hole in the recording medium, and the part where the recording playback hole is formed does not reflect the laser beam, and the part without a hole reflects a portion of the laser beam. Therefore, a method is used to detect the difference in the reflected light intensity (the so-called Phillips method). The main problem with this method is that the recording layer does not lie and has a large absorption wheel for some parts, and low heat conduction due to the formation of pores due to the melting and oxidation of the constituent materials of the recording layer. Having a car causes the laser light to emit heat and increase the temperature.
(Formation of holes requires the formation of a special seal (recording sensitivity), but on the other hand, in order to read and reproduce records), it is necessary to use a laser beam reflection in the part where there are no holes. However, these required properties are fundamentally contradictory to each other. Therefore, in general, it is reasonable to use a recording layer with characteristics such as an absorption wheel of 60 degrees and a reflectance of about 40 degrees for light around 5100 am, which is the wavelength of semiconductor laser light. It is being measured.

% KFi, which uses a semiconductor laser for high output, has not yet been developed, and at the time of writing, the collection vehicle for the recording layer was relatively large and light and heavy; however, on the other hand, during playback. It is preferable that the KFi brass symbol partial emissivity is large. This is because the signal/1/s sound ratio (SA ratio) during reproduction depends on the reflectance.

The recording layer, which is a thin film of a metal or metalloid having a low melting point, is laminated with a reflective thin film of a metal such as U, which exhibits a higher reflectance to laser light than the recording layer, and A second method O in which a laminated film is supported on a substrate
Things are also known.

In this method, recording is performed using the above-mentioned 0J11+ method and ri4
Recording is performed by irradiating the laser beam with the laser to form holes in the recording layer, and during SO playback, the reflective thin film is exposed at the portion where the holes are formed in the recording layer. The reflectance increases and S? Since the reflectance is relatively small in areas with large holes and thin areas, this second method uses this fact to detect the difference in light reflection intensity. The fact that collection vehicles are expensive for sightseeing and their thermal conductivity is low is important in terms of improving recording sensitivity.

The present inventor aims to solve the above-mentioned drawbacks of recording media using hole formation by improving the recording sensitivity, reproduction sensitivity, and recording durability (compared to the conventional method), which limits the quality of the recording layer. Hatsunabe<m will research. This large attack, unrecorded state ■tehiro,
It is possible that there will be more than 90 C song trucks for racing sightseeing (
Therefore, the reflectance can be set to 1096 or less),
Moreover, in order to avoid the O-type recording part due to low-output laser sightseeing, the recording part has a recording layer that can reflect light with a reflectance of at least 3G and can be read out with a laser beam. I have found that this is at least necessary.

Firstly, the present inventor has developed an ultrafine particle OI aggregate (aggr-・g
Inspired by the fact that at@g ) is generally a black body that is very good against light, it is an aggregate of ultrafine particles of a metal or metalloid that has a low melting point that can be melted or evaporated by irradiation with laser light. A good thin film, that is, a thin film with a structure in which the ultrafine particles of the above-mentioned low melting point metal or metalloid are aggregated with a large number of voids so small that they can be seen with an electron microscope, is created. The idea was to use it as the recording layer of an optical recording medium.

After carrying out various experiments, it was found that such a thin film was extremely suitable for the intended purpose.

and a thin film consisting of an aggregate of such ultrafine particles of a low melting point metal or metalloid, with a particle size of 600 to 1001000.
Ji1ML9 has shown that an ultrafine particle thin film exhibiting a ll convergence of 6o or more for n-wavelength radar light can be put to practical use as an optical recording layer.

Therefore, the present inventor has submitted the application filed by the present applicant in 1986.
-172021, the title of the invention [Optical Recording Medium, October 29, 1981, 11a), describes an optical recording medium that performs recording, recording and reproducing using loser light, which melts when exposed to laser sightseeing irradiation. Or, it is a thin film with a structure in which evaporable semimetallic OS mold particles are so small that they can be observed with an electronic hazy microscope, and have a structure in which they aggregate with a large number of voids.
The present invention has proposed an optical recording medium characterized by having a recording layer made of a thin film of metal or drop metal O, which exhibits a particle size of 60 or more when exposed to a laser beam with a wavelength of 0.00 am. In this optical recording medium, the above-mentioned O recording layer is provided on a substrate or on a reflective metal film supported by a substrate, and is a thin film having a structure in which ultrafine metal or semimetal particles are aggregated. In addition to the cross-section of the recording layer, the recording layer has a circular hole, that is, a hole, which penetrates the film until it reaches the substrate or metal reflection 111. This is a system in which a recording section (C&#t) is formed as a recording section.

The inventor further conducted research. As a result, instead of using a thin film made of ultrafine particle aggregates of metals or metalloids with low melting points as described above as the recording layer, metals with high melting points that do not melt under laser sightseeing irradiation are used. In addition, we used the fallen horse, which is an aggregate of ultra-fine particles of company metal, as a laser light absorption layer, and made it into a layer of the same size and thickness.
When an optical recording medium is produced by laminating a layer on a low melting point metal or filament metal, only the portion of the low melting point metal or semimetal thin film that is irradiated with the recording laser beam melts,
The molten metal generated during graining penetrates into the adjacent high-melting-point metal or metalloid ultrafine particle aggregate thin film, and the grains enclose or metalize the ultrafine particles, resulting in metallic luster. It has been found that the banding becomes dense and has a dense structure, and the surface of the band can become highly reflective. This kind of area with improved reflectance is formed, and the difference in reflectance to the laser beam can be seen between the (recorded) S part and the unrecorded part that has not been irradiated with the laser. Therefore, the sensitivity of recording and playback is excellent.

Therefore, the gist of the present invention is to provide an optical recording medium that performs recording and recording using a laser beam, which is made of a thin film of a metal or semimetal with a low melting point that can be melted by irradiation with the laser beam. It is a thin film having a structure in which ultrafine particles of a metal or metalloid having a melting point high enough to not melt when irradiated with a laser beam or aggregated with a large number of voids small enough to be observed with an electron microscope are formed. It is made by laminating thin films of aggregates of ultrafine particles of metals or metalloid metals that exhibit an absorption rate of 604 or more for laser light with a wavelength of mm, and this thin film of aggregates of ultrafine particles can be adjacent to each other by irradiation with recording laser light. An optical recording medium characterized by having a film thickness large enough to form a recording portion with improved light reflectivity through penetration of molten metal that is generated when a thin film of a low melting point metal or semimetal is melted. It is in.

In the present invention, as a material for a thin film of ultrafine particle aggregates, it should be melted by laser light irradiation! A metal or metalloid of Class III is used which has a higher melting point than the low melting point metal or metalloid used in the low melting point gold or metalloid film. For example, the ultrafine particle aggregate O material contains In, Au,
Sn, Zn, To, Se, Bi, Zn, t
'b.

Bi, Ag, Ni, k'e, Co, %i
n, At, Sit ML Tit cr.

Cu, Pd, etc. can be used. The metal or metalloid ultrafine particle aggregate thin film used here absorbs laser light during recording and is heated to melt the low melting point metal layer on the back surface, so it itself has a low melting point. There is no need for it, and mold costs include having a high absorption rate of laser light, good adhesion to the substrate, and being stable with little change over time such as oxidation. If the thickness is too thick, the heat conduction to the low melting point layer will be small, and it will also be difficult for the low melting point metal to penetrate into the surface, so the thinner the layer is, the better.

However, if the thickness is too thin, sufficient blackness cannot be obtained, and the reflection effect of the low melting point metal layer on the back side will appear, so the preferred thickness is 1.
It is about 00 to 5001. Ultrafine particles have a diameter of 100 to 3
00 A% is preferably in the range of 100 to 200 A, and when the layer of the ultrafine metal particle aggregate in the present invention is viewed under an electron microscope, the ultrafine particles of such a size have V voids of the same size. It is observed that a large number of (voids) are interconnected and aggregated while intervening. The proportion of the total volume occupied by ultrafine particles in the thin film's volumetric capacity, that is, the filling wheel, can be calculated by observing the cross section of the recording layer with an electron microscope, and the filling aC is 90 or less, preferably I
It is preferable that the score is Q to 90 excellent, and the shout is 30 to 80 poor.

If the pus is present (such as ultrafine particles of SM metal), measure the saturation magnetization value of the film, and calculate this value from the metal's complete tc fB solid state (i.e., there is virtually no internal space H). l! The filling wheel of a film can also be determined by comparing it with the value of the saturation magnetization of a film of II-thickness. Filling of ultrafine particles a [
If the thickness is too high, penetration of low melting point metals will be inhibited, and if the thickness is low, the strength of the film will be low and the adhesion will also be poor. front? (If the eC is 1 or more, the blackness will decrease and a metallic luster will appear.) However, the filling car is preferably in the range of 40 to 50%.

The ultrafine metal particle aggregate thin layer 111 of the present invention contains 0.
There are some materials whose visual light absorption rate is extremely high, exceeding qo*. These thin films are composed of OMi particles with a diameter of several hundred
It is thought that the filling cars are aggregated and layered at about 30 to 90 mm, and the absorption rate is high due to light scattering + absorption of norasmon. Such a gold-supercompensatory particle I
RjIIk body thinning is not only expensive but also has the advantage of having a smaller heat conduction vehicle than ordinary gold kl and thin film.

Low melting point metal or metal lI4 in the optical recording medium of the present invention
The properties required for a thin film include a low melting point that can be melted by laser beam irradiation, high reflective properties, good wettability with the thin film of ultrafine particle aggregates, and easy penetration into the surface of the thin film, and resistance to changes over time. It is a town that is less stable. Preferred metals include In, 8n, Pb, Zn, Bi
, 8b, T@, 8@ Seedashi, constituent materials of ultrafine particle aggregate thin film and J! Elm low melting point metals or metalloids are selected. The IIIJIi is preferably 500 to 2000 A, and if the film is too thick, the heat capacity will increase.
The laser/measuring power required for recording becomes large.

Furthermore, if it is too thin, it will not be able to penetrate sufficiently into the surface of the adjacent layer, making it impossible to improve the reflection. For film formation,
If general PVD technology is used,
Yattering, ion rolling, etc. can be used.

However, during olfactory formation, the substrate temperature increases ().
It's a must-have.

In a non-exploding optical recording medium, a thin film layer made of aggregates of ultrafine particles of gold or semimetal having a relatively high melting point is provided directly on the substrate, and then a layer of K is melted by laser irradiation. Thin films of low melting point metals can be laminated. In this case, the optical recording medium of the present invention can form a recording portion with improved reflectance by laser beam irradiation from the substrate m,
The reproduction of the recorded information can be performed by emitting a reading laser beam from the substrate side and detecting the laser beam reflected by the recording section.

Furthermore, in the optical recording medium of the present invention, a thin layer of ultrafine particle aggregates of a metal or metalloid having a relatively high melting point is laminated on a thin film of a low melting point metal or metalloid supported by a substrate. be able to. In this case, recording and playback are performed by irradiating the laser from the side opposite to the substrate. And the narrow side KF' where the recording medium is not covered with the substrate! It is also possible to provide a surface-facing membrane made of a material having low thermal conductivity, such as silica or silicone comb, and having a thickness of about 100 μm.

In the present invention, the thin film layer of aggregates of ultrafine metal or metalloid particles can be formed using conventionally known vapor deposition techniques, ion derating techniques, snow-melting techniques, plasma deposition techniques, etc. It can be formed on a substrate using a zonation method or the like. For example, by adjusting the gold evaporation rate, the degree of vacuum of the evaporation equipment, the evaporation time, and the various operating conditions such as Light collection vehicles, etc. can be adjusted.

In particular, the metal or The film is formed by a method of vapor deposition by directing a flow of metalloid vapor (hereinafter also referred to as oblique vapor deposition method), or alternatively, by applying a non-reactive gas such as argon, helium, or nitrogen gas at a low pressure of 10 to 10 torr. Filled Arashi: ft inside the room, on top of the held substrate, conventional evaporation method, ion derating method, sputtering method,
Alternatively, when forming a film of a metal or metalloid using the L plasma deposition method, an aggregate of ultrafine metal or metalloid particles exhibiting a visible light absorption rate of 9011 or higher and a filling wheel of 10 to 80. 〉 thin film can be formed.

Therefore, in the second aspect of the present invention, vapor of a metal or metalloid having a high melting point of charcoal, which does not melt when irradiated with laser light, is applied to the surface of the substrate from an oblique direction on a substrate that is transparent to laser viewing. A vacuum evaporation operation is carried out by applying a vacuum evaporation operation to the above-mentioned ultrafine metal or semi-metallic particles, which are small enough to be observed with an electron microscope, and have a structure of agglomeration with a large number of empty particles. A thin film of an aggregate of ultrafine metal or metalloid particles exhibiting an absorption rate of 604 or more for laser light with a wavelength of 600 to 1000 um is formed as a layer with a thickness in the range of 100 to 500 μm, and then To provide a complete method for manufacturing an optical recording medium, which is characterized in that a vapor-deposited film of a low-melting point metal or a metal coat that can be melted by laser light irradiation is formed by a conventional method.

#30 In the present invention, metals or semi-metals with a high melting point that do not melt when irradiated with laser light are placed on a substrate held in a low-pressure inert gas atmosphere of 10 to 101-bar. A large number of metal lI films are formed by a vaporization FLR method, an ion derating method, a sputtering method, or a desputter deposition method.

A film-forming operation is carried out, whereby (i) the ultrafine particles of the metal or powdered metal are so small that they can be observed with an electron microscope;
A thin film with a cohesive structure with many voids,
Regarding laser light with a wavelength of 600 to 1000 nm6
A thin layer of ultrafine aggregates of metal or metalloid particles exhibiting an absorption rate of 0 or more is formed as a layer with a thickness in the range of 100 to 500x, and then melted by irradiation with laser light. A method for producing an optical recording medium O is also provided, characterized in that a low melting point metal or semi-41XSO thin film is formed by conventional vapor deposition.

Next, various forms of the optical recording medium of the present invention will be explained with reference to the drawings.

FIG. 1 shows that a sufficient amount of 114.
A thin film ink made of a metal with a relatively high melting point or an agglomerate of ultrafine particles 2 is placed on the L'S as a recording layer, and on top of this, a dense thin film of a metal with a low melting point or a semimetal is placed. 1 and 2 schematically show the state of recording by laser irradiation on the optical recording medium of the present invention, which has a 1!4 layered structure. A protective film 7 is provided on the surface of the low melting point metal thin film layer. Regarding the illustrated optical recording medium, during recording, the laser beam is focused on the substrate 10 side or C) the low melting point metal thin film 4, and the gold in the portion SK in the thin layer 114 is melted. This shows a state in which at least a portion of the molten metal penetrates into the interparticle gaps in the thin film 3, forming a recording portion 6 in which the surface reflection g becomes high.

The playback of the recording (reading *ka) is based on the reading comprehension and 1
This is done by detecting a laser beam that is irradiated from a narrow part of the recording section 6 and reflected by the highly reflective surface 6' of the recording section 6.

Next, the present invention will be explained with reference to examples.

Example 1 An optical recording medium according to the present invention was manufactured using a vapor deposition apparatus shown schematically in FIG.

In this vapor deposition apparatus, a molten metal pool 10 of the metal to be vaporized is provided on the bottom surface 9' of a vacuum vessel 9, and the inside of the vessel 9 is heated by the operation of an exhaust gas connected to an exhaust port 11.
A high vacuum of 10 torr can be achieved. A substrate 1i on which a thin film of ultrafine particle aggregates of the metal to be deposited is fixed to a substrate holder 8, and the surface receiving the deposition is arranged in a direction oblique to the flow direction of the metal vapor rising from the molten metal pool. . This substrate is rotated about the shaft 8' of the substrate holder 2 to 3 times per minute for 1 minute, so that the thickness of the deposited film is equal to that of the substrate! The metal is uniformly deposited over one polymer, and the metal deposited on the surface does not form a dense thin film, forming an aggregate of ultrafine particles.
ll film.

In this example, the incident angle at which the metal vapor hits the substrate surface 1iIK was 80°. The degree of vacuum in the container 9 is set to below t-2810-' Torr, and nickel powder (nickel powder) is removed from the sol 10 in which the nickel gold powder is melted at a rate of 0.2 t/min.
Deposited on M & I A substrate (thickness 121) to a film thickness of 30
Form a nickel diagonal in-line film of 0A, then adjust the position of the holder so that the space between the substrate stations is perpendicular to the direction of metal vapor flow, and then deposit indium densely on top of this film using a normal evaporation method. An optical recording disk was prepared by forming a film with a thickness of 500 Å and further applying a -9 1'=L chloride retentive film. The cross section of the above obliquely evaporated nickel film was examined using an electron microscope (
%i1.1i200-30 when observed under 100,000 times magnification)
It was found that the structure consisted of ultrafine nickel metal particles with a large number of fine voids. The surface W+ of this obliquely evaporated nickel film appears black and its absorption rate is 6.
9 for laser light with a wavelength of 00 to 1000 nm
When irradiated with a semiconductor laser with an output of 15 - that emits a laser with a wavelength of K 1130 (reflectance of 9g6), the distribution part with a metallic luster and an average diameter of 1 string becomes a diagonal nickel vapor deposited layer. May be formed.

The reading section Shiraser party reflected in this recording section (Wl!!
The reflectance at 830 nm) was about 40 mm, and the recording portion could be clearly detected from the difference in reflectance.

Example 2 An optical recording medium according to the present invention was manufactured using a vapor deposition apparatus schematically shown in FIG.

In this vapor deposition apparatus, a molten metal pool 10 of the metal to be vaporized is provided in the bottom 9' of a vacuum container 9, and the inside of the container 9 is heated from 10 to
It can create a vacuum of 10 torr. This device has
A conduit 12 through which an inert gas such as argon can enter and exit is installed, making it possible to create an inert gas W atmosphere at a low pressure of 10 to 10 Torr within the vacuum chamber 9.

Furthermore, an ionizing electric current 111M in an appropriate form, such as a net plate shape or a grid shape, is provided between the substrate hole 8' and the molten metal 114f-hole 10 of the metal to be vapor-deposited. It is connected to the DC power supply 14 on the other side. When a DC voltage is applied to this layer, the metal vapor rising from Sol 1G is ionized by the voltage effect, and the metal is deposited on the substrate using the ion rating technique.

In the above apparatus, the ftrc with the container 9 completely evacuated
While introducing argon gas to a pressure of 0.1 Torr through a specialist 12, gold (Au) is evaporated to a thickness of 400 μm on the PMM substrate in an argon atmosphere of 0.1 Torr. At this time, a DC voltage of 12 KV was applied to a mesh-shaped electrode placed in front of the substrate to generate a cyclaw discharge, thereby performing ion derating. The substrate holder was rotated to ensure uniform deposition, and a thin film of about 400A of ultrafine gold particle aggregates was formed.A tin (Sm) gold area was deposited on each of the nine spindles to a thickness of 500mm using a normal vapor deposition method. When deposited in dense layers, a laminated structure was formed. After vapor deposition, a protective layer of vinyl chloride is applied to the surface. When the spectral curve of the surface of the aggregate layer of ultrafine gold particles of this sample was measured, it was found that the spectral curve was 600 to 1000.
It has a wavelength of nm, an absorption rate of 94 tatami, and a reflection rate of 6 yen. 8
It was recorded with a 30 nm semiconductor laser, and a metallic luster was obtained.The reflectance of the part 1!

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an optical recording medium according to the present invention. FIGS. 2 and 3 are illustrative views of equipment suitable for manufacturing the optical recording medium according to the present invention. 1... Optical recording medium substrate, 2... Ultrafine metal particles, 5... Ultrafine metal particle aggregate layer, 4...
- low melting point metal layer, 5... melting part of the low melting point metal layer, 8... substrate holder, 9......
Vacuum container, 1°...IHf molten metal pool.

Claims (1)

[Scope of Claims] [In an optical recording medium that performs recording and reproduction using a laser beam, a laser beam is formed on a thin film of a low melting point metal or metalloid + ZJ that can be melted by irradiation with laser light. A thin film having a structure in which ultrafine metal or metalloid particles having a high melting point that does not melt when irradiated with light are aggregated with a large number of voids that are small enough to be observed according to the electron image theory.60
60 for laser light with a wavelength of 0 to + 000 nm
It is made by laminating thin films of aggregates of ultrafine particles of metals or metalloid metals exhibiting an absorption wheel of qII or more, and the ultrafine particle aggregates are exposed adjacently by irradiation with recording laser light. An optical film characterized by having a film thickness large enough to form a recording area with improved light reflectivity by receiving the molten metal that is generated when a thin film of a low melting point coalesce or metalloid metal is melted. recoding media. 2. A thin film of an aggregate of ultrafine metal or metalloid particles is placed on a substrate transparent to laser light.J1 A patent claim in which a thin film of a metal or metalloid with a low melting point is deposited on top of this thin film. The optical E-sickle medium according to item 1. 8. A low melting point metal supported by a substrate or an ultra-thin ta
2. The optical recording medium according to claim 1, wherein a thin film of aggregates of ultrafine particles of a metal X-ray semimetal is laminated on the O. 4. The optical recording medium according to claim 2, wherein a protective film #i is provided on the second side of the low melting point metal or metalloid maple. 6. The proportion of the total volume occupied by the ultrafine particles of metal or cowshed per unit volume of the thin film of the aggregate of the ultrafine particles of metal or cowshed, that is, the filling rate is 90 qIb or less, preferably 10 to 90. The optical recording medium according to claim 1, which has a molecular weight of 30 to 80. 66 On a substrate that is transparent to laser light, a vacuum evaporation operation is performed by applying a metal or metal having a high melting point that does not melt Fi when irradiated with laser light from an oblique direction to the surface of the substrate. As a result, the ultrafine particles of the metal or metalloid are aggregated across a large number of voids that are small enough to be observed with an electron microscope, forming four thin films of 60
G - Ultrafine metal or metalloid particles O# that exhibit a plate ratio of 60 or more when exposed to laser light with a wavelength of #000 m! A thin film of 100 to 500 μm is formed as a layer, and then a low melting point metal or semimetal 011 film that can be melted by partial irradiation is deposited on top of it by a conventional method. A method for producing an optical recording medium, which is characterized in that it can be stored. 7.10 ~ 10) - A thin film of a metallic X-ray semimetal with a melting point 1 degree O higher than that which will not melt in a single beam of laser radiation is deposited on a substrate held in a low-pressure inert gas O atmosphere of 10 to 10). Vapor deposition method, ion! Lethein! It is formed by the method, the suffix tsuttering method, or the Fifteen drawing method. A film-forming operation was performed, and as a result of this, the ultrafine particles of the above-mentioned metal or Hironaka metal were observed under an electron microscope as J1! It is a thin film with a structure that is aggregated over a large number of O voids that are small enough to be detected, and has a structure of 6
Laser light with a wavelength of 00 to 11,000 IL is 60
A thin film of agglomerates of ultrafine particles of metal or cattle block having an absorption force of 11 or more is formed as a layer with a film thickness in the range of 100 to 500 A, and then a low melting point film that can be melted by irradiation with laser light is applied thereon. A method for manufacturing an optical recording medium, characterized in that a thin film of metal or semimetal is formed by conventional vapor deposition.