WO2020230357A1 - 情報記録媒体とその製造方法 - Google Patents

情報記録媒体とその製造方法 Download PDF

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Publication number
WO2020230357A1
WO2020230357A1 PCT/JP2019/051040 JP2019051040W WO2020230357A1 WO 2020230357 A1 WO2020230357 A1 WO 2020230357A1 JP 2019051040 W JP2019051040 W JP 2019051040W WO 2020230357 A1 WO2020230357 A1 WO 2020230357A1
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Prior art keywords
film
dielectric film
recording medium
layer
information recording
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PCT/JP2019/051040
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English (en)
French (fr)
Japanese (ja)
Inventor
昇吾 冨田
晶夫 槌野
理恵 児島
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パナソニックＩｐマネジメント株式会社
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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/2403—Layers; Shape, structure or physical properties thereof
    • G11B7/24035—Recording layers
    • G11B7/24038—Multiple laminated recording layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B7/2433—Metals or elements of Groups 13, 14, 15 or 16 of the Periodic Table, e.g. B, Si, Ge, As, Sb, Bi, Se or Te
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/257—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers
    • G11B7/2578—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers consisting essentially of inorganic materials
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/26—Apparatus or processes specially adapted for the manufacture of record carriers

Definitions

  • the present disclosure relates to a high-density information recording medium for recording or reproducing information by optical means and a method for manufacturing the same.
  • Optical discs have evolved into CDs (Compact Discs), DVDs (Digital York Discs), and BDs (Blu-ray (registered trademark) Discs).
  • BD the BD-XL standard was established in June 2010, and a three-layer disc (optical disc with three information layers) conforming to this standard has a recording capacity of 33.4 gigabytes (GB) per information layer. It has a recording capacity of 100 GB on one side.
  • the commercial optical disc standard "Archival Disc” was established in March 2014 (see, for example, Non-Patent Document 1).
  • the archive disc achieves a higher recording density than BD by adopting the land and groove recording method.
  • the roadmap of the archive disk standard is designed to gradually increase the recording capacity per disk.
  • the first generation system is 300 GB
  • the second generation system is 500 GB
  • the first-generation 300GB archiver disc enables recording and playback of 300GB of information per disc by providing three-layer discs capable of storing 150GB of information on both sides of the substrate.
  • a second-generation 500GB archival disc it is necessary to increase the recording capacity of the single-sided triple-layer disc to 250GB.
  • One of the means for increasing the recording capacity of the medium for optically recording information is to reduce the size of the shortest recording mark and increase the recording density in one information layer.
  • the signal becomes higher frequency and the S / N (S: signal, N: noise) of the disk is lowered due to the influence of system noise, and the reproduction durability (reproduction light is applied to the recording mark).
  • An index showing the degree of deterioration of signal quality when irradiation is continued) deteriorates.
  • Each information layer is composed of three films, and is referred to as a first dielectric film, a recording film, and a second dielectric film from the far side to the near side when viewed from the laser beam irradiation surface.
  • the recording film When the recording film is irradiated with laser light, the recording film changes its shape and a signal is recorded.
  • Dielectric film included in the information layer has a large effect on the reproduction durability, conventional, materials containing ZrO 2, SiO 2 and In 2 O 3 (ZrO 2 -SiO 2 -In 2 O 3) is used (See, for example, Patent Documents 1 and 2).
  • the present disclosure provides an information recording medium capable of obtaining good reproduction durability even with a minute recording mark.
  • the present inventors have studied various materials for the first dielectric film in order to obtain good regeneration durability. As a result, it was found that good regeneration durability can be obtained by applying a dielectric material containing Si and C to the first dielectric film. That is, the present invention is as follows.
  • An information recording medium that includes three or more information layers and records or reproduces information by irradiation with laser light. Of the three or more information layers, the information layer located farthest from the laser beam irradiation surface is designated as the first information layer.
  • the first dielectric film from the far side to the near side when viewed from the laser beam irradiation surface, is formed by the first information layer.
  • the recording film and the second dielectric film are included in this order.
  • An information recording medium in which the first dielectric film contains at least Si, C, oxygen and / or nitrogen.
  • the recording film contains at least W, Cu, Mn, and oxygen. Further, it contains at least one element M selected from Nb, Mo, Ta, Zn, and Ti.
  • the metal element contained in the recording film is The following formula (1): W x Cu y Mn z M 100-x-y-z (atomic%) (In the above formula (1), 15 ⁇ x ⁇ 45, 0 ⁇ y ⁇ 30, 0 ⁇ z ⁇ 40, and 60 ⁇ x + y + z ⁇ 98),
  • [3] The information recording medium according to [1] or [2], wherein the first dielectric film further contains at least one dielectric selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5 .
  • Si and C contained in the first dielectric film, oxygen and / or nitrogen are designated as D1, and at least one dielectric selected from SnO 2 , ZnO, In 2 O 3 and Ta 2 O 5 is designated as D2.
  • the first dielectric film is The following formula (2): (D1) p (D2) 100-p (atomic%) (In the above formula (2), 50 ⁇ p ⁇ 100), The information recording medium according to [3], which satisfies the above conditions. [5] The information recording medium according to any one of [1] to [4], wherein the second dielectric film contains an oxide of at least one element D3 selected from Zr, In, Sn, Zn, and Si. ..
  • the information layers are arranged on both sides via a substrate.
  • the information layer has uneven grooves on the substrate for recording and reproducing information, and when viewed from the irradiation side of the laser beam, both the near groove (groove) and the far side groove (land) are formed.
  • a method for manufacturing an information recording medium which includes a step of forming three or more information layers, and a step of forming at least one of the information layers by sputtering using a target D containing at least Si and C.
  • a method for manufacturing an information recording medium which comprises a step of forming the first dielectric film.
  • the composition ratio of W, Cu, Mn excluding oxygen and the element M of the target m used in the step of forming the recording film is the following formula (1): W x Cu y Mn z M 100-x-y-z (atomic%) (In the above formula (1), 15 ⁇ x ⁇ 45, 0 ⁇ y ⁇ 30, 0 ⁇ z ⁇ 40, and 60 ⁇ x + y + z ⁇ 98),
  • the method for manufacturing an information recording medium according to [9] which satisfies the above conditions.
  • the step of forming the first dielectric film uses a target containing at least Si and C and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 and Ta 2 O 5 .
  • the information recording medium according to the embodiment of the present invention has an information layer showing good reproduction durability, and enables the realization of a highly reliable and high recording density information recording medium.
  • FIG. 1 is a cross-sectional view of the information recording medium 100 according to the first embodiment of the present disclosure.
  • the information recording medium is an information recording medium including three or more layers of information and recording or reproducing information by irradiation with laser light.
  • the first information layer which is at least one of the three or more information layers, is the first dielectric film, the recording film, and the first information layer from the far side to the near side when viewed from the laser irradiation surface.
  • the second dielectric film is included in this order,
  • the first dielectric film contains at least Si, C, oxygen, and / or nitrogen.
  • the recording film contains at least W, Cu, Mn, and oxygen, and at least one selected from Nb, Mo, Ta, Zn, and Ti.
  • the metal element contained in the recording film is The following formula (1): W x Cu y Mn z M 100-x-y-z (atomic%) (In the above formula (1), 15 ⁇ x ⁇ 45, 0 ⁇ y ⁇ 30, It is preferable to satisfy 0 ⁇ z ⁇ 40 and 60 ⁇ x + y + z ⁇ 98).
  • FIG. 1 shows a cross section of an optical information recording medium.
  • the information recording medium 100 of the present embodiment is provided with three information layers (six layers in total) on both sides via the substrate 1 to record and reproduce information, and irradiates the laser beam 6 from the cover layer 4 side.
  • a multi-layer optical information recording medium capable of recording and reproducing information for each information layer.
  • the one farthest from the laser light source is called the "L0 layer”
  • the next farthest is called the "L1 layer”
  • the one closest to the laser light source is called the "L2 layer”.
  • the laser light 6 is a laser light in a bluish-purple region having a wavelength of around 405 nm.
  • the information recording medium 100 is a double-sided information recording medium in which the A-side information recording medium 101 and the B-side information recording medium 102 are bonded together.
  • the back surfaces (opposite sides of the surface having the information layer) of the substrates 1 are bonded by the bonding layer 5.
  • the A-side information recording medium 101 and the B-side information recording medium 102 have L0 layer 10, L1 layer 20, and L2 layer 30 sequentially laminated as information layers on the substrate 1 via intermediate separation layers 2 and 3, respectively. Further, a cover layer 4 is provided on the L2 layer 30.
  • the L1 layer 20 and the L2 layer 30 are transparent information layers.
  • the surface on the side closer to the laser beam 6 is conveniently referred to as a "groove” in the present specification, and the surface on the side farther from the laser beam 6 is called. Is called “land” for convenience.
  • the capacity per information layer is set to, for example, 83.4 GB. It is possible. Since the information recording medium 100 can record and reproduce in six information layers, it is possible to obtain an information recording medium having a capacity of 500 GB.
  • the guide groove may also be formed in the intermediate separation layers 2 and 3 as described later.
  • the effective reflectance of the three information layers can be controlled by adjusting the reflectances of the L0 layer 10, the L1 layer 20 and the L2 layer 30, and the transmittances of the L1 layer 20 and the L2 layer 30, respectively.
  • the reflectance of each information layer measured in a state where the three information layers are stacked is defined as the effective reflectance. Unless otherwise specified, unless otherwise stated as "effective”, it refers to the reflectance measured without stacking.
  • the functions, materials, and thicknesses of the substrate 1, the intermediate separation layer 2, the intermediate separation layer 3, the cover layer 4, and the bonding layer 5 will be described.
  • the substrate 1 is preferably a disk-shaped transparent substrate.
  • a resin such as polycarbonate, amorphous polyofin, hydrogen silsesquioxane, or polymethylmethacrylate, or glass can be used.
  • an uneven guide groove for guiding the laser beam 6 may be formed on the surface of the substrate 1 on the recording film 12 side.
  • the thickness of the substrate 1 is about 0.5 mm and the diameter is about 120 mm.
  • the guide groove is formed on the substrate 1, the groove on the side closer to the laser beam 6 is called a “groove” and the groove on the side farther from the laser beam 6 is called a “land” as described above.
  • the step between the groove surface and the land surface is preferably 10 nm to 50 nm. Further, in the first embodiment, the distance between the groove lands was set to about 0.225 ⁇ m.
  • the intermediate separation layers 2 and 3 are made of an acrylic resin such as a photocurable resin (particularly an ultraviolet curable resin) or a slow-acting thermosetting resin, and the laser light 6 efficiently reaches the L0 layer 10 and the L1 layer 20. As described above, it is preferable that the light absorption is small with respect to the light having the wavelength ⁇ used for recording / reproduction.
  • the intermediate separation layers 2 and 3 are used to distinguish the focus positions of the L0 layer 10, the L1 layer 20 and the L2 layer 30, and the thickness is determined by the numerical aperture (NA) of the objective lens and the wavelength ⁇ of the laser beam 6. It is necessary that the depth of focus is ⁇ Z or more. Assuming that the reference of the light intensity of the focal point is 80% of the case of no aberration, ⁇ Z can be approximated by the equation (1z).
  • the thicknesses of the intermediate separation layer 2 and the intermediate separation layer 3 are preferably different values. Further, in the intermediate separation layer 2 and the intermediate separation layer 3, uneven guide grooves may be formed on the incident side of the laser beam 6. In the first embodiment, the distance between the groove lands was set to about 0.225 ⁇ m.
  • the bonding layer 5 is made of, for example, a resin such as a photocurable resin (particularly an ultraviolet curable resin) or a slow-acting thermosetting resin, and the A-side information recording medium 101 and the B-side information recording medium 102 are adhered to each other. .. Further, the bonding layer 5 may be provided with a film that blocks the laser beam 6.
  • the thickness of the bonded layer 5 is preferably about 5 ⁇ m to 80 ⁇ m, more preferably about 20 ⁇ m to 50 ⁇ m.
  • the total thickness of the intermediate separation layer 2, the intermediate separation layer 3, and the cover layer 4 may be set to be 100 ⁇ m. ..
  • the intermediate separation layer 2 may be set to 25 ⁇ m
  • the intermediate separation layer 3 may be set to 18 ⁇ m
  • the cover layer 4 may be set to 57 ⁇ m.
  • the L0 layer 10 is formed by laminating at least the first dielectric film 11, the recording film 12, and the second dielectric film on the substrate in this order.
  • the first dielectric film 11 has a function of adjusting the optical phase difference to control the signal amplitude and a function of adjusting the bulge of the recording mark to control the signal amplitude. Further, the first dielectric film 11 has a function of suppressing the invasion of water into the recording film 12 and a function of suppressing the escape of oxygen in the recording film 12 to the outside.
  • the first dielectric film 11 is a film containing at least Si, C, oxygen, and / or nitrogen.
  • SiC has high thermal conductivity, when the recording film is irradiated with laser light, the heat generated by the light absorption of the recording film can be efficiently released from the recording film. Further, since SiC has high adhesion to the substrate 1, good regeneration durability can be obtained by applying SiC to the first dielectric film 11.
  • the first dielectric film 11 has SnO 2 , ZnO, and In 2 O in order to improve the conductivity of the target so that more stable DC sputtering can be performed and to increase the refractive index of the first dielectric film 11. It is preferable to contain at least one dielectric D2 selected from 3 and Ta 2 O 5 .
  • the conductivity of the target can be improved, and in forming the first dielectric film 11, the first dielectric film 11 can be further formed. It is possible to perform stable DC sputtering.
  • the first dielectric film 11 contains Ta 2 O 5 .
  • the material SiC x O y where oxygen is taken into the SiC denoted as convenience SiC-O
  • the material SiC x N z which nitrogen is incorporated into SiC and convenience SiC-N notation To do.
  • the material SiC x O y N z in which oxygen and nitrogen are incorporated into SiC is referred to as SiC-ON for convenience.
  • composition systems of the first dielectric film 11 include (SiC-O) -SnO 2 , (SiC-O) -ZnO, (SiC-O) -In 2 O 3 , and (SiC-O) -Ta.
  • Si and C contained in the first dielectric film and oxygen and / or nitrogen are designated as D1, and at least one selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5.
  • D2 be one dielectric
  • the first dielectric film has the following equation (2): (D1) p (D2) 100-p (atomic%) (In the above formula (2), 50 ⁇ p ⁇ 100), It is preferable to satisfy.
  • the conductivity of the target can be improved and more stable DC sputtering can be performed.
  • the refractive index of the first dielectric film can be increased.
  • p in the formula (2) is 50 ⁇ p ⁇ 100, good regeneration durability can be obtained because the proportion of SiC contained in the first dielectric film is large.
  • the composition of the first dielectric film 11 can be analyzed by, for example, an X-ray microanalyzer (XMA), an electron probe microanalyzer (EPMA), or a Rutherford backscattering analysis method (RBS). Similarly, the composition of other dielectric films described later can be analyzed by these methods.
  • XMA X-ray microanalyzer
  • EPMA electron probe microanalyzer
  • RBS Rutherford backscattering analysis method
  • the thickness of the first dielectric film may be, for example, 5 nm or more and 40 nm or less. If it is less than 5 nm, the protective function is deteriorated, and the invasion of water into the recording film 12 may not be suppressed. If it exceeds 40 nm, the reflectance of the L0 layer 10 may decrease.
  • the recording film 12 preferably contains W, Cu, Mn, and oxygen, and further contains at least one element M selected from Nb, Mo, Ta, Zn, and Ti.
  • W, Cu, Mn, and oxygen for example, oxygen is desorbed by irradiation with laser light 6, and a film expansion portion serving as a recording mark is formed. Since the formation of the film expansion portion is an irreversible change, the L0 layer provided with the recording film 12 becomes a write-once information layer.
  • the x (W amount) in the formula (1) is preferably 15 or more and 45 or less, more preferably 20 ⁇ x ⁇ 40, and even more preferably 22 ⁇ x ⁇ 35.
  • the recording film 12 can be formed by stable DC sputtering, and the L0 layer having good recording / reproducing characteristics can be obtained.
  • DC sputtering can be satisfactorily carried out when x is x ⁇ 15.
  • an alloy target in which W, Cu, Mn, and element M are mixed is used, DC sputtering can be satisfactorily performed when x is 20 ⁇ x ⁇ 40.
  • x When x is less than 15, the shape of the recording film is unlikely to change, and the signal quality of the reproduced signal deteriorates. If x exceeds 45, the recording sensitivity of the L0 layer 10 deteriorates, and a large laser power may be required for recording.
  • Y (Cu amount) preferably satisfies 0 ⁇ y ⁇ 30, more preferably 10 ⁇ y ⁇ 30, and even more preferably 13 ⁇ y ⁇ 28.
  • the light absorption rate of the recording film 12 can be adjusted to optimize the recording sensitivity of the L0 layer 10, and good reproduction durability can be obtained.
  • y is larger than 0, DC sputtering can be performed satisfactorily.
  • y exceeds 30, the light absorption rate of the recording film 12 increases and the recording sensitivity improves, so that the reproduction durability may deteriorate.
  • Z (Mn amount) preferably satisfies 0 ⁇ z ⁇ 40, more preferably 10 ⁇ z ⁇ 35, and even more preferably 15 ⁇ z ⁇ 30.
  • z preferably satisfies 0 ⁇ z ⁇ 40, more preferably 10 ⁇ z ⁇ 35, and even more preferably 15 ⁇ z ⁇ 30.
  • x + y + z is 60 or more and 98 or less, and it is more preferable that 65 ⁇ x + y + z ⁇ 85 is satisfied.
  • x + y + z is 60 ⁇ x + y + z ⁇ 98, the recording / reproducing characteristics of the L0 layer 10 become good. Further, the refractive index and the extinction coefficient of the recording film 12 are optimized, and the reflectance of the L0 layer 10 can be increased. If x + y + z is less than 60, the element M becomes excessive and the signal quality of the reproduced signal deteriorates.
  • the element M contained in the recording film 12 is at least one element M 1 selected from Nb, Mo, Ta, and Ti.
  • the refractive index of the recording film 12 can be increased, the reflectance of the L0 layer can be improved, and the sputtering rate can be increased. Therefore, the recording film 12 can be formed with good productivity.
  • the refractive index of the recording film 12 is 1.8 or more and the effective reflectance of the L0 layer 10 is 2.8% or more, good signal quality can be obtained.
  • the refractive index is 2.0 or more
  • the effective reflectance of the L0 layer 10 is 3.0% or more, and better signal quality can be obtained.
  • the refractive index is 2.2 or more, the effective reflectance of the L0 layer 10 is 3.2% or more, and very good signal quality can be obtained.
  • the recording film 12 may further contain Zn in addition to the element M 1 .
  • Zn is not to affect the refractive index and extinction coefficient of the recording film 12, W, Cu, Mn, is 100 combined number of atoms of the element M 1 and Zn, at 20 atomic% or less It may be there.
  • the composition of the recording film 12 is, for example, W-Cu-Mn-Nb-O, W-Cu-Mn-Mo-O, W-Cu-Mn-Ta-O, W-Cu-Mn-Ti-O, W. -Cu-Mn-Nb-Zn-O, W-Cu-Mn-Mo-Zn-O, W-Cu-Mn-Ta-Zn-O, W-Cu-Mn-Ti-Zn-O, W-Cu -Mn-Nb-Mo-O, W-Cu-Mn-Nb-Ta-O, W-Cu-Mn-Nb-Ti-O, W-Cu-Mn-Mo-Ta-O, W-Cu-Mn-Mo-Ti-O, W-Cu-Mn-Mo-Ti-O, W-Cu-Mn-Mo-Ti-O, W-Cu-Mn-Ta-Ti-O, W-Cu-Mn-Mo-T
  • the thickness of the recording film 12 may be, for example, 10 nm or more and 50 nm or less, and particularly preferably 20 nm or more and 40 nm or less. If the thickness of the recording film 12 is less than 10 nm, the recording film 12 does not expand sufficiently, so that good recording marks may not be formed, and as a result, the channel bit error rate deteriorates. If the thickness of the recording film 12 exceeds 50 nm, the time required for film formation of the recording film 12 (sputtering time) becomes long, and the productivity may decrease.
  • composition of the recording film 12 can be analyzed by, for example, an X-ray microanalyzer (XMA), an electron probe microanalyzer (EPA), or a Rutherford backscattering analysis method (RBS).
  • XMA X-ray microanalyzer
  • EPA electron probe microanalyzer
  • RBS Rutherford backscattering analysis method
  • the second dielectric film 13 has a function of adjusting the optical phase difference to control the signal amplitude and a function of controlling the bulge of the recording pit to control the signal amplitude. .. Further, the second dielectric film 13 has a function of suppressing the invasion of water into the recording film 12 from the intermediate separation layer 2 side and a function of suppressing the escape of oxygen in the recording film 12 to the outside. The second dielectric film 13 also has a function of suppressing the mixing of organic substances from the intermediate separation layer 2 into the recording film 12.
  • the composition of the second dielectric film 13 is, for example, ZrO 2 , SiO 2 , In 2 O 3 , ZnO, SnO 2 , ZrO 2- SiO 2 , ZrO 2-In 2 O 3 , ZrO 2- ZnO, ZrO 2- SnO 2, SiO 2 -In 2 O 3, SiO 2 -ZnO, SiO 2 -SnO 2, In 2 O 3 -ZnO, In 2 O 3 -SnO 2, ZnO-SnO 2, ZrO 2 -SiO 2 -In 2 O 3, ZrO 2 -SiO 2 -ZnO , ZrO 2 -SiO 2 -SnO 2, ZrO 2 -In 2 O 3 -ZnO, ZrO 2 -In 2 O 3 -SnO, ZrO 2 -In 2 O 3 -SnO 2, ZrO 2 -In 2 O 3 -ZnO, ZrO 2 -In 2 O 3
  • the second dielectric film 13 is, for example, a nanometer-order thin film formed by sputtering. Therefore, the oxide contained in the second dielectric film 13 may not have a stoichiometric composition, strictly speaking, due to the lack of oxygen and / or metal during sputtering and the inevitable mixing of impurities. For this reason, in the present embodiment, the oxide contained in the second dielectric film 13 does not necessarily have to have a stoichiometric composition.
  • the materials represented by the stoichiometric composition in the present specification include those which are not strictly stoichiometrically composed due to lack of oxygen and / or metal, contamination of impurities, and the like. To do.
  • the thickness of the second dielectric film 13 is preferably, for example, 5 nm or more and 30 nm or less. If the thickness is less than 5 nm, it may not be possible to suppress the invasion of water into the recording film 12. If the thickness is larger than 30 nm, the reflectance of the L0 layer 10 may decrease.
  • the specific thicknesses of the first dielectric film 11, the recording film 12, and the second dielectric film 13 are described in the matrix method (see, for example, Hiroshi Kubota, "Wave Optics", Iwanami Shoten, 1971, Chapter 3). It can be designed by calculation based on. By adjusting the thickness of each film, the reflectances of the recording film 12 when it is unrecorded and when it is recorded, and the phase difference of the reflected light between the recording unit and the unrecorded unit are adjusted to adjust the reproduction signal. It is possible to optimize the signal quality of.
  • the L1 layer 20 is formed by laminating at least the first dielectric film 21, the recording film 22, and the second dielectric film 23 on the surface of the intermediate separation layer 2 in this order.
  • the function of the first dielectric film 21 is the same as the function of the first dielectric film 11 of the L0 layer 10 described above.
  • the first dielectric film 21 also has a role of bringing the intermediate separation layer 2 and the L1 layer 20 into close contact with each other.
  • the composition of the first dielectric film 21 is not limited to that of the first dielectric film 11. This is because the L1 layer 20 is closer to the incident surface of the laser beam 6 than the L0 layer 10, so that the reflectance of the L1 layer 20 can be determined without specifying the composition of the first dielectric film 21. Because it is easy to make it expensive. Therefore, the first dielectric film 21 may be formed using the materials exemplified in relation to the first dielectric film 11 or the second dielectric film 13, or the first dielectric film 21 may be another It may be formed by using a material, for example, a material having a refractive index smaller than that used in the first dielectric film 11.
  • composition of the first dielectric film 21 for example, ZrO 2, ZnO, SnO 2 , In 2 O 3, ZrO 2 -ZnO, ZrO 2 -SnO 2, ZrO 2 -In 2 O 3, ZnO-SnO 2, ZnO -In 2 O 3, SnO 2 -In 2 O 3, ZrO 2 -ZnO-SnO 2, ZrO 2 -ZnO-In 2 O 3, ZrO 2 -SnO 2 -In 2 O 3, ZnO-SnO 2 -In 2 It may be O 3 , ZrO 2- ZnO-SnO 2-In 2 O 3, or the like.
  • the thickness of the first dielectric film 21 may be 10 nm or more and 50 nm or less. If the thickness of the first dielectric film 21 is less than 10 nm, the adhesion to the intermediate separation layer 2 may be lowered, and the protective function of suppressing the intrusion of water into the recording film 22 may be lowered. If the thickness of the first dielectric film 21 exceeds 50 nm, the reflectance of the L1 layer 20 may decrease. In addition, the time required for forming the first dielectric film 21 (sputtering time) may become long, and the productivity may decrease.
  • the function of the recording film 22 is the same as the function of the recording film 12 of the L0 layer 10 described above. As described above, since the L1 layer 20 tends to have a higher reflectance than the L0 layer 10, the composition of the recording film 22 is not limited to that of the recording film 12. Therefore, the recording film 22 may be formed using materials similar to those exemplified in connection with the recording film 12, or may contain other materials such as W, Cu, and Mn, but may include the element M. It may be formed using no material.
  • the recording film 22 may be formed of a material having a smaller z than the recording film 12 of the L0 layer 10, giving priority to ensuring high transmittance.
  • z may satisfy, for example, 10 ⁇ z ⁇ 30. You may increase x by the amount that z is decreased.
  • the recording film 22 may also be made of the same material as the recording film of the first generation archival disc. In that case, since the sputtering target used for manufacturing the first-generation archival disk can also be used for manufacturing the information recording medium of the present embodiment, it is possible to improve productivity or reduce costs. is there. More specifically, for example, the recording film 22 may be formed of W—Cu—Mn—Zn—O.
  • the film thickness of the recording film 22 may be 15 nm or more and 50 nm or less, and particularly preferably 25 nm or more and 45 nm or less. If the thickness of the recording film 22 is less than 15 nm, the recording film 22 does not expand sufficiently, so that good recording marks may not be formed, and as a result, the channel bit error rate deteriorates. If the thickness of the recording film 22 exceeds 50 nm, the time required for film formation of the recording film 22 (sputtering time) becomes long, and the productivity may decrease.
  • the function of the second dielectric film 23 is the same as the function of the second dielectric film 13 of the L0 layer 10 described above.
  • the composition of the second dielectric film 23 is not particularly limited. This is because the L1 layer 20 is closer to the incident surface of the laser beam 6 than the L0 layer 10, so that the reflectance of the L1 layer 20 is set even if the composition of the second dielectric film 23 is not specified. This is because it is easy to increase the reflectance.
  • the second dielectric film 23 can be formed using a material related to the first dielectric film 11 or the second dielectric film 13. Alternatively, the second dielectric film 23 may be formed by using another material, for example, a material having a refractive index smaller than that of the material used in the second dielectric film 13.
  • the thickness of the second dielectric film 23 may be, for example, 5 nm or more and 30 nm or less. If the thickness is less than 5 nm, it may not be possible to suppress the invasion of water into the recording film 22. If the thickness is larger than 30 nm, the reflectance of the L1 layer 20 may decrease.
  • the L2 layer 30 is formed by laminating at least the first dielectric film 31, the recording film 32, and the second dielectric film 33 on the surface of the intermediate separation layer 3 in this order.
  • the function of the first dielectric film 21 is the same as the function of the first dielectric film 11 of the L0 layer 10 described above.
  • the first dielectric film 21 also has a role of bringing the intermediate separation layer 2 and the L1 layer 20 into close contact with each other.
  • the structure of the L2 layer 30 is basically the same as that of the L1 layer 20.
  • the first dielectric film 31 has the same function as the first dielectric film 21 of the L1 layer 20, and therefore has the same function as the first dielectric film 11 of the L0 layer 10.
  • the first dielectric film 31 also has a role of bringing the intermediate separation layer 3 and the L2 layer 30 into close contact with each other.
  • the composition of the first dielectric film 31 is not particularly limited as in the case of the first dielectric film 21. Since the L2 layer 30 is located on the outermost side, it is easy to increase the reflectance of the L2 layer 30 without specifying the composition of the first dielectric film 31.
  • the first dielectric film 31 can be formed using the materials exemplified in relation to the first dielectric film 11 and the first dielectric film 21 of the L0 layer 10, or other materials can be used. May be formed.
  • the first dielectric film 31 may be formed of, for example, a material having a refractive index smaller than that of the materials used in the first dielectric film 11 and the first dielectric film 21.
  • the thickness of the first dielectric film 31 may be 10 nm or more and 50 nm or less. When the thickness of the first dielectric film 31 is less than 10 nm, the adhesion between the first dielectric film 31 and the intermediate separation layer 3 is lowered, and a protective function of suppressing the intrusion of moisture into the recording film 32 is provided. May decrease. If the thickness of the first dielectric film 31 exceeds 50 nm, the reflectance of the L2 layer 30 may decrease. In addition, the time required for film formation of the first dielectric film 31 (sputtering time) becomes long, and the productivity may decrease.
  • the function of the recording film 32 is the same as that of the recording film 22 of the L1 layer 20. Therefore, it has the same function as the recording film 12 of the L0 layer 10.
  • the composition of the recording film 32 is not limited to that of the recording film 12 because the L2 layer 30 is located on the outermost side and tends to have a higher reflectance than the L1 layer 20 and the L0 layer 10. Therefore, the recording film 32, like the recording film 22, may be formed using the same materials as those exemplified in connection with the recording film 12, or may contain other materials such as W, Cu, and Mn. However, it may be formed by using a material that does not contain the element M.
  • the recording film 32 may be formed of a material having a smaller z than the recording film 12 of the L0 layer 10 and the recording film 22 of the L1 layer 20, giving priority to ensuring high transmittance.
  • z may satisfy, for example, 5 ⁇ z ⁇ 30. You may increase x by the amount that z is decreased.
  • the recording film 22 may also be made of the same material as the recording film of the first generation archival disc.
  • the recording film 32 may be formed of W—Cu—Mn—Zn—O.
  • the film thickness of the recording film 32 may be 15 nm or more and 50 nm or less, and particularly preferably 25 nm or more and 45 nm or less. If the thickness of the recording film 32 is less than 15 nm, a good recording mark may not be formed because the recording film 32 does not expand sufficiently, and as a result, the channel bit error rate deteriorates. If the thickness of the recording film 32 exceeds 50 nm, the time required for film formation of the recording film 32 (sputtering time) becomes long, and the productivity may decrease.
  • the function of the second dielectric film 33 has the same function as the second dielectric film 23 of the L1 layer 20, and therefore has the same function as the second dielectric film 13 of the L0 layer 10.
  • the composition of the second dielectric film 33 is not particularly limited as in the case of the second dielectric film 23. This is because the L2 layer 30 is located on the outermost side, so that the reflectance is likely to be higher than that of the L1 layer 20 and the L0 layer 10 without specifying the composition of the second dielectric film 33. Therefore, the second dielectric film 33 can be formed by using a material related to the first dielectric film 11 or the second dielectric film 13 of the L0 layer. Alternatively, it may be formed by using another material, for example, a material having a refractive index smaller than that used in the first dielectric film 11.
  • the thickness of the second dielectric film 33 may be, for example, 5 nm or more and 30 nm or less. If the thickness is less than 5 nm, it may not be possible to suppress the invasion of water into the recording film 32. If the thickness is larger than 30 nm, the reflectance of the L2 layer 30 may decrease.
  • the first dielectric films 11, 21, 31, the recording films 12, 22, 32, and the second dielectric films 13, 23, 33 are a mixture of oxides, nitrides, oxynitrides, and carbides constituting them. It may be formed by RF sputtering or DC sputtering using a sputtering target. Further, these films may be formed by RF sputtering or DC sputtering under the introduction of oxygen and / or nitrogen using a sputtering target containing no oxygen or nitrogen.
  • Sputtering targets for each oxide, nitride, oxynitride, and carbide may be attached to separate power sources and simultaneously subjected to RF sputtering or DC sputtering to form these films (multi-sputtering method). RF sputtering and DC sputtering may be performed at the same time.
  • a sputtering target made of a single metal or an alloy, or a sputtering target of an oxide, a nitride, an oxynitride, or a carbide is attached to a separate power source, and oxygen and / or if necessary.
  • Examples thereof include a method of RF sputtering at the same time while introducing nitrogen, and a method of DC sputtering at the same time.
  • These films may be formed by a method of DC sputtering.
  • the recording method of the information recording medium 100 may be any of Constant Linear Velocity (CLV) having a constant linear velocity, Constant Angular Utility (CAV) having a constant rotation speed, Zoned CLV, and Zoned CAV.
  • CLV Constant Linear Velocity
  • CAV Constant Angular Utility
  • Zoned CLV Zoned CAV
  • Zoned CAV Zoned CAV
  • the recording and reproduction of information on the information recording medium 100 of the present embodiment may be carried out by an optical system having a numerical aperture NA of the objective lens of 0.91, or an optical system having an NA> 1 may be carried out. ..
  • an optical system having a numerical aperture NA of the objective lens of 0.91 or an optical system having an NA> 1 may be carried out.
  • NA numerical aperture
  • the optical system Solid Immersion Lens (SIL) or Solid Immersion Mirror (SIM) may be used.
  • the intermediate separation layers 2 and 3 and the cover layer 4 may have a thickness of 5 ⁇ m or less.
  • an optical system using near-field light may be used.
  • the method for manufacturing an information recording medium includes a step of forming three or more information layers, and the step of forming at least one of the information layers is the first step of forming the information layer by sputtering using a target D containing at least Si and C. 1 Includes a step of forming a dielectric film.
  • the step of forming at least one of the information layers includes at least W, Cu, and Mn, and at least one selected from Nb, Mo, Ta, Zn, and Ti.
  • a step of forming a recording film containing at least W, Cu, Mn, and oxygen by sputtering using the target m containing the element M, and further containing at least one element M is further included.
  • the composition ratio of W, Cu, Mn excluding oxygen and the element M of the target m used in the step of forming the recording film is the following formula (1): W x Cu y Mn z M 100-x-y-z (atomic%) (In the above formula (1), 15 ⁇ x ⁇ 45, 0 ⁇ y ⁇ 30, 0 ⁇ z ⁇ 40, and 60 ⁇ x + y + z ⁇ 98), It is preferable to satisfy.
  • the method for manufacturing an information recording medium includes a step of forming three or more information layers.
  • the step of forming at least one of the information layers comprises at least W, Cu, Mn and oxygen.
  • a step of forming a recording film containing at least one element M selected from Nb, Mo, Ta, Zn, and Ti, and It comprises the step of forming a first dielectric film containing at least Si, C, oxygen and / or nitrogen.
  • the step of forming the recording film includes a sputtering step using a target containing at least W, Cu, and Mn, and further containing at least one element M selected from Nb, Mo, Ta, Zn, and Ti.
  • the step of forming the first dielectric film preferably includes a sputtering step using a dielectric target containing at least Si and C.
  • the first dielectric film 11, the recording film 12, and the second dielectric film 13 constituting the L0 layer 10 can be formed by a sputtering method, which is one of the vapor phase film forming methods.
  • the information recording medium 100 may have a substrate 1.
  • the substrate 1 (for example, thickness 0.5 mm, diameter 120 mm) is arranged in the film forming apparatus. First, the first dielectric film 11 is formed. At this time, if a spiral guide groove is formed on the substrate 1, the first dielectric film 11 is formed on the guide groove side.
  • the first dielectric film 11 is sputtered in a process gas atmosphere or a mixed gas atmosphere of a process gas and a reaction gas (for example, oxygen gas or nitrogen gas) using a sputtering target according to a desired composition.
  • a process gas for example, Ar gas, Kr gas, or Xe gas, but Ar gas is advantageous in terms of cost. This applies to any sputtering in which the atmosphere gas of the sputtering is a process gas or a mixed gas thereof.
  • the target may include in the form of carbide, oxide-carbide, nitride-carbide, oxynitride-carbide.
  • the oxide may be formed by reactive sputtering carried out in an atmosphere containing oxygen gas.
  • the nitride may be formed by reactive sputtering carried out in an atmosphere containing nitrogen gas.
  • the oxynitride may be formed by reactive sputtering performed in an atmosphere containing oxygen gas and nitrogen gas.
  • the specific resistance value of the target is preferably 1 ⁇ ⁇ cm or less. This facilitates DC sputtering.
  • the target having a composition containing the element D2 has high conductivity, and it becomes easy to stably form the first dielectric film 11 by DC sputtering.
  • the composition of the target may be adjusted so that the desired composition of the first dielectric film 11 can be obtained.
  • the composition of the target for forming the first dielectric film 11 is (SiC-O) -Sn, (SiC-O) -Sn-Ta, (SiC-N) -Sn, (SiC-N) -Sn-Ta, (SiC-ON) -Sn, (SiC-ON) -Sn-Ta and the like are preferably used.
  • oxides or nitrides or oxynitrides in the target eg, (SiC-O) -SnO 2 , (SiC-O) -SnO 2- Ta 2 O 5 , (SiC-N) -SnO 2 , (SiC-N) -SnO 2- Ta 2 O 5 , (SiC-ON) -SnO 2 , (SiC-ON) -SnO 2- Ta 2 O 5 and the like are preferably used.
  • the recording film 12 is formed on the first dielectric film 11.
  • the recording film 12 is subjected to sputtering in a process gas atmosphere or a mixed gas atmosphere of a process gas and a reaction gas using a target composed of a metal alloy or a metal-oxide mixture, depending on its composition. Can be formed. Since the thickness of the recording film 12 is thicker than that of a dielectric film such as the first dielectric film 11, the recording film 12 is DC sputtering or pulse DC sputtering, which can be expected to have a higher film formation rate than RF sputtering, in consideration of productivity. It is preferable to form a film using. Since a large amount of oxygen is contained in the recording film 12, it is preferable to mix a large amount of oxygen gas in the atmospheric gas.
  • the recording film 12 may be formed by performing multi-sputtering.
  • the composition of the target is W-Cu-Mn-Nb-O, W-Cu-Mn-Ta-O, W-Cu-Mn-Nb-Zn-O, W-Cu-Mn-Ta-Zn-O, W-Cu-Mn-Nb-Ta-O, It may be W-Cu-Mn-Nb-Ta-Zn-O or the like.
  • the recording film 12 may consist of at least two or more laminated films of recording materials having different compositions.
  • the reflectance and recording sensitivity of the L0 layer 10 can be adjusted by changing the composition of the recording material constituting the laminated film or the film thickness ratio of the laminated film.
  • the second dielectric film 13 is formed on the recording film 12.
  • the second dielectric film 13 can be formed by performing sputtering in a process gas atmosphere or a mixed gas atmosphere of a process gas and a reaction gas using a target according to the composition of the second dielectric film 13. Further, the second dielectric film 13 may be formed by performing multi-sputtering. The second dielectric film 13 can be formed by using a target according to a desired composition.
  • the target composition for forming the second dielectric film 13 is Zr-In-O, Zr-Si-In-O or the like is preferably used.
  • oxides in the target eg, ZrO 2-In 2 O 3 , ZrO 2- SiO 2-In 2 O 3 and the like are preferably used.
  • the intermediate separation layer 2 is formed on the second dielectric film 13.
  • a resin for example, an acrylic resin
  • a photocurable resin particularly an ultraviolet curable resin
  • a slow-acting thermosetting resin is applied onto the L0 layer 10 and spin-coated, and then the resin is cured. It can be formed by making it.
  • the transfer substrate (mold) having a groove having a predetermined shape formed on the surface is spin-coated in a state of being in close contact with the resin before curing, and then the resin is cured.
  • the intermediate separation layer 2 may be formed by a method of peeling the transfer substrate from the cured resin.
  • the intermediate separation layer 2 may be formed in two steps. Specifically, the portion occupying most of the thickness is first formed by the spin coating method, and then the portion having the guide groove is formed by the spin coating method. It may be formed in combination with transfer by a transfer substrate.
  • the L1 layer 20 is formed. Specifically, first, the first dielectric film 21 is formed on the intermediate separation layer 2.
  • the first dielectric film 21 can be formed by the same method as the above-mentioned first dielectric film 11 using a target according to a desired composition.
  • the recording film 22 is formed on the first dielectric film 21.
  • the recording film 22 can be formed by the same method as the recording film 12 described above, using a target according to a desired composition.
  • the second dielectric film 23 is formed on the recording film 22.
  • the second dielectric film 23 can be formed by the same method as the above-mentioned second dielectric film 13 using a target according to a desired composition.
  • the intermediate separation layer 3 is formed on the second dielectric film 23.
  • the intermediate separation layer 3 can be formed in the same manner as the above-mentioned intermediate separation layer 2.
  • the L2 layer 30 is formed.
  • the L2 layer 30 can be formed basically in the same manner as the above-mentioned L1 layer 20.
  • the first dielectric film 31 is formed on the intermediate separation layer 3.
  • the first dielectric film 31 can be formed by the same method as the above-mentioned first dielectric film 11 using a target according to a desired composition.
  • the target can identify oxides, nitrides, oxynitrides, and carbides contained in the target by X-ray diffraction, for example.
  • the target structure may contain composite oxides, composite oxynitrides, mixed oxides, mixed oxynitrides, suboxides, and high oxidation number oxides. This also applies to targets for forming the first dielectric films 11, 21, recording films 12, 22, 32, and second dielectric films 13, 23, 33.
  • the recording film 32 is formed on the first dielectric film 31.
  • the recording film 32 can be formed by the same method as the recording film 12 described above, using a target according to a desired composition.
  • the second dielectric film 33 is formed on the recording film 32.
  • the second dielectric film 33 can be formed by the same method as the above-mentioned second dielectric film 13 using a target according to a desired composition.
  • any of the dielectric films and recording films 12, 22, and 32 may be formed with the power supply during sputtering set to 10 W to 10 kW and the pressure in the film forming chamber set to 0.01 Pa to 10 Pa.
  • the cover layer 4 is formed on the second dielectric film 33.
  • the cover layer 4 is formed by applying a resin such as a photocurable resin (particularly an ultraviolet curable resin) or a slow-acting thermosetting resin on the second dielectric film 33, spin-coating the resin, and then curing the resin. it can.
  • the cover layer 4 may be formed by laminating a disk-shaped substrate 1 made of a resin such as polycarbonate, amorphous polyolefin, hydrogen silsesquioxane, or polymethylmethacrylate, or glass.
  • a resin such as a photocurable resin (particularly an ultraviolet curable resin) or a slow-acting thermosetting resin is applied to the second dielectric film 33, and the substrate 1 is brought into close contact with the applied resin and spun.
  • the cover layer 4 can be formed by applying a coating to spread the resin uniformly and then curing the resin.
  • the substrate 1 and the L0 layer 10 may include a disk identification code (for example, BCA (Burst Cutting Area)).
  • a disk identification code for example, BCA (Burst Cutting Area)
  • the identification code can be attached by melting and vaporizing the polycarbonate using a CO 2 laser or the like after molding the substrate 1.
  • the identification code when the identification code is attached to the L0 layer 10, the identification code can be attached by recording on the recording film 12 or disassembling the recording film 12 using a semiconductor laser or the like.
  • the step of attaching the identification code to the L0 layer 10 may be carried out after the formation of the second dielectric film 13, the formation of the intermediate separation layer 2, the formation of the cover layer 4, or the formation of the bonding layer 5.
  • the B-side information recording medium 102 can be manufactured in the same manner as the A-side information recording medium 101.
  • the direction of rotation of the spiral may be opposite to that of the guide groove of the substrate 1 of the A-side information recording medium 101, or may be the same direction.
  • a photocurable resin (particularly an ultraviolet curable resin) is uniformly applied to the surface of the substrate 1 opposite to the surface provided with the guide groove, and the B-side information recording medium
  • the surface of the substrate 1 of 102 opposite to the surface provided with the guide groove is attached to the coated resin.
  • the resin is irradiated with light and cured to form the bonded layer 5.
  • the lagging curable photocurable resin is uniformly applied to the A-side information recording medium 101 and then exposed to light, and then the B-side information recording medium 102 is attached to form the bonded layer 5. May be good.
  • the information recording medium 100 having information layers on both sides according to the first embodiment can be manufactured.
  • Example 1 In this embodiment, an example of the information recording medium 100 shown in FIG. 1 will be described. The following is a method for manufacturing the information recording medium 100 of this embodiment.
  • the configuration of the A-side information recording medium 101 will be described.
  • a polycarbonate substrate (diameter 120 mm, thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the L0 layer 10 was formed on the substrate 1.
  • a target containing SiC or SiC and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5 is used as the dielectric in the present invention.
  • a target consisting substantially of W 25 Cu 21 Ta 21 Zn 5 Mn 28- O as a recording film 12 at 11.5 nm W 25 Cu 21 Ta 21 Zn 5 Mn 28- O at 31 nm, second dielectric.
  • a target consisting essentially (ZrO 2) 25 (SiO 2 ) 25 (in 2 O 3) 50 (mol%) was deposited at 8.5 nm in sequence by a sputtering method.
  • the metal element ratio (atomic%) is described as the element ratio, and the following is also described in the same manner.
  • an oxide of W 25 Cu 21 Ta 21 Zn 5 Mn 28 (atomic%) is described as W 25 Cu 21 Ta 21 Zn 5 Mn 28- O.
  • the first dielectric film 11 was formed in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC target and using a DC power supply (1 kW).
  • SiC-N was formed, it was carried out using a DC target (1 kW) in an Ar + N 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC target.
  • SiC-ON was formed, it was carried out using a DC power source (1 kW) in an atmosphere of Ar + O 2 + N 2 (flow rate: 12 + 10 + 10 sccm) using a SiC target.
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the intermediate separation layer 2 was first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin was cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 2 is formed.
  • the thickness of the intermediate separation layer 2 is about 25 ⁇ m.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply.
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare an A-side information recording medium 101.
  • the configuration of the B-side information recording medium 102 will be described.
  • a polycarbonate substrate (thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared. The direction of rotation of the spiral of the guide groove was opposite to that of the substrate 1 of the A-side information recording medium 101 described above.
  • the L0 layer 10 was formed on the substrate 1.
  • a target containing SiC or SiC and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5 is used as the dielectric in the present invention.
  • a target consisting substantially of W 25 Cu 21 Ta 21 Zn 5 MN 28- O as a recording film 12 at 11.5 nm W 25 Cu 21 Ta 21 Zn 5 Mn 28- O at 31 nm, second dielectric.
  • a target consisting essentially (ZrO 2) 25 (SiO 2 ) 25 (in 2 O 3) 50 (mol%) was deposited at 8.5 nm in sequence by a sputtering method.
  • the first dielectric film 11 was formed in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC target and using a DC power supply (1 kW).
  • SiC-N was formed, it was carried out using a DC target (1 kW) in an Ar + N 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC target.
  • SiC-ON was formed, it was carried out using a DC power source (1 kW) in an atmosphere of Ar + O 2 + N 2 (flow rate: 12 + 10 + 10 sccm) using a SiC target.
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the method of forming the intermediate separation layer 2 is the same as that of the intermediate separation layer 2 of the A-side information recording medium 101 described above, but the rotation direction of the spiral of the guide groove is different from that of the intermediate separation layer 2 of the A-side information recording medium 101 described above. The direction was reversed. This enables simultaneous playback on both sides.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply (5 kW).
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare a B-side information recording medium 102.
  • the ultraviolet curable resin is uniformly applied to the surface of the A-side information recording medium 101 opposite to the surface on which the guide groove of the substrate 1 is provided, and the guide groove of the substrate 1 of the B-side information recording medium 102 is formed.
  • the resin was bonded to the surface opposite to the provided surface, and the resin was cured by ultraviolet rays to form a bonded layer 5 (thickness of about 35 ⁇ m).
  • the reproduction durability at 8 times speed was evaluated in 1-1 to 1-18 and Comparative Example 1-1.
  • the reproduction durability was evaluated using a pulse tech evaluation machine (ODU-1000).
  • the wavelength of the laser beam 6 of the evaluation machine was 405 nm, the numerical aperture NA of the objective lens was 0.91, and the information was recorded in the groove and the land.
  • the linear speed of recording was 18.06 m / s (500 GB-8 times speed) and the linear speed of reproduction was 18.06 m / s (500 GB-8 times speed).
  • the data bit length was 51.3 nm, and the 83.4 GB density per information layer was recorded.
  • the laser light 6 which was superposed (modulated) at a high frequency of 2: 1 was used as the reproduced light. Random signals (2T to 12T) were recorded, and the signal quality was evaluated as d-MLSE (Distribution Deployed-Maximum Likelihood Sequence Error Estimation).
  • a random signal is recorded in an isolated groove, and the random signal of the groove located in the center of the recorded track is reproduced at a reproduction power of 4.0 mW and a linear velocity of 18.06 m / s.
  • the reproduction was performed, and the quality was judged based on the amount of change in d-MLSE between the first and 1 million times of repeated reproductions.
  • the conductivity of the target was judged to be good or bad depending on the possibility of DC sputtering. Specifically, the target capable of DC sputtering and having a high film formation rate was designated as A (very good), the target capable of DC sputtering was designated as B (good), and the target not capable of DC sputtering was designated as D (impractical). ..
  • the refractive index of the first dielectric film 11 was measured with an ellipsometer, and the quality was judged according to the following criteria.
  • the refractive index of the first dielectric film 11 is A (very good) when it is 2.1 or more, B (good) when it is 1.9 or more and less than 2.1, and C (practical level) when it is 1.7 or more and less than 1.9. Less than 1.7 was defined as D (impractical).
  • each disc was comprehensively evaluated according to the following criteria.
  • the evaluation criteria are as follows.
  • ⁇ The reproduction durability is judged as A, the conductivity and refractive index of the target are both judged as A or B, and the judgment as B is one or less.
  • ⁇ The reproduction durability is judged as A or B, and the conductivity and refractive index of the target are not judged as D. However, this does not apply when it is included in ⁇ .
  • ⁇ is the most preferable information recording medium. ⁇ is a more preferable information recording medium. ⁇ is a preferred information recording medium. X is not practical as an information recording medium.
  • Table 1 shows the results of the A-side information recording medium 101.
  • the conductivity of the target is improved and more stable DC sputtering is performed. Confirmed that it can be done. Further, it was confirmed that the refractive index of the first dielectric film 11 was increased by containing any of SiC—O, SiC—N, and SiC-ON and In 2 O 3 or Ta 2 O 5 . ..
  • the first dielectric film 11 contains any of SiC, SiC-N, and SiC-ON and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5.
  • the overall evaluation was ⁇ , and better recording / playback characteristics were obtained.
  • Example 2 In this embodiment, an example of the information recording medium 100 shown in FIG. 1 will be described. The following is a method for manufacturing the information recording medium 100 of this embodiment.
  • the configuration of the A-side information recording medium 101 will be described.
  • a polycarbonate substrate (diameter 120 mm, thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention is 11 using a target containing SiC and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5.
  • the first dielectric film 11 is formed in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC-D2 target and using a DC power supply (1 kW). went.
  • (SiC-N) -D2 was formed, it was carried out using a DC power source (1 kW) in an Ar + N 2 atmosphere (flow rate: 12 + 20 sccm) using a SiC-D2 target.
  • (SiC-ON) -D2 was formed, it was carried out using a DC power source (1 kW) in an atmosphere of Ar + O 2 + N 2 (flow rate: 12 + 10 + 10 sccm) using a SiC-D2 target.
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the intermediate separation layer 2 was first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin was cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 2 is formed.
  • the thickness of the intermediate separation layer 2 is about 25 ⁇ m.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply.
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare an A-side information recording medium 101.
  • the configuration of the B-side information recording medium 102 will be described.
  • a polycarbonate substrate (thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the direction of rotation of the spiral of the guide groove was opposite to that of the substrate 1 of the A-side information recording medium 101 described above.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention is 11 using a target containing SiC and at least one dielectric D2 selected from SnO 2 , ZnO, In 2 O 3 , and Ta 2 O 5.
  • the first dielectric film 11 is formed in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW), and (SiC-N).
  • Ar + N 2 atmosphere flow rate: 12 + 20 sccm
  • (SiC-ON) -D2 was formed, it was carried out in an atmosphere of Ar + O 2 + N 2 (flow rate: 12 + 10 + 10 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the method of forming the intermediate separation layer 2 is the same as that of the intermediate separation layer 2 of the A-side information recording medium 101 described above, but the rotation direction of the spiral of the guide groove is different from that of the intermediate separation layer 2 of the A-side information recording medium 101 described above. The direction was reversed. This enables simultaneous playback on both sides.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply (5 kW).
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare a B-side information recording medium 102.
  • the ultraviolet curable resin is uniformly applied to the surface of the A-side information recording medium 101 opposite to the surface on which the guide groove of the substrate 1 is provided, and the guide groove of the substrate 1 of the B-side information recording medium 102 is formed.
  • the resin was bonded to the surface opposite to the provided surface, and the resin was cured by ultraviolet rays to form a bonded layer 5 (thickness of about 35 ⁇ m).
  • the first dielectric film 11 of the side A information recording medium 101 and the side B information recording medium 102 (SiC-O) 50 (SnO 2 ) 50 (mol%) (SiC-O) 48 (SnO 2 ) 52 (mol%) (SiC—O) 50 (ZnO) 50 (mol%) (SiC-O) 48 (ZnO) 52 (mol%) (SiC-O) 50 (In 2 O 3 ) 50 (mol%) (SiC-O) 48 (In 2 O 3 ) 52 (mol%) (SiC-O) 50 (Ta 2 O 5 ) 50 (mol%) (SiC-O) 48 (Ta 2 O 5 ) 52 (mol%) (SiC-N) 50 (SnO 2 ) 50 (mol%) (SnO 2 ) 52 (mol%) (SiC-ON) 50 (SnO 2 ) 50 (mol%) (SiC-ON) 48 (SnO 2 ) 50 (mol%) (SiC-ON) 48 (SnO 2
  • the reproduction durability at 8 times speed was evaluated in 2-1 to 2-12.
  • the reproduction durability was evaluated using a pulse tech evaluation machine (ODU-1000).
  • the wavelength of the laser beam 6 of the evaluation machine was 405 nm, the numerical aperture NA of the objective lens was 0.91, and the information was recorded in the groove and the land.
  • the linear speed of recording was 18.06 m / s (500 GB-8 times speed) and the linear speed of reproduction was 18.06 m / s (500 GB-8 times speed).
  • the data bit length was 51.3 nm, and the 83.4 GB density per information layer was recorded.
  • the laser light 6 which was superposed (modulated) at a high frequency of 2: 1 was used as the reproduced light. Random signals (2T to 12T) were recorded, and the signal quality was evaluated as d-MLSE (Distribution Deployed-Maximum Likelihood Sequence Error Estimation).
  • a random signal is recorded in an isolated groove, and the random signal of the groove located in the center of the recorded track is reproduced at a reproduction power of 4.0 mW and a linear velocity of 18.06 m / s.
  • the reproduction was performed, and the quality was judged based on the amount of change in d-MLSE between the first and 1 million times of repeated reproductions.
  • the conductivity of the target was judged to be good or bad depending on the possibility of DC sputtering. Specifically, the target capable of DC sputtering and having a high film formation rate was designated as A (very good), the target capable of DC sputtering was designated as B (good), and the target not capable of DC sputtering was designated as D (impractical). ..
  • the refractive index of the dielectric film 11 was judged to be good or bad based on the following criteria.
  • the refractive index of the first dielectric film 11 is A (very good) when it is 2.1 or more, B (good) when it is 1.9 or more and less than 2.1, and C (practical level) when it is 1.7 or more and less than 1.9. Less than 1.7 was defined as D (impractical).
  • each disc was comprehensively evaluated according to the following criteria.
  • the evaluation criteria are as follows.
  • ⁇ The reproduction durability is judged as A, the conductivity and refractive index of the target are both judged as A or B, and the judgment as B is one or less.
  • ⁇ The reproduction durability is judged as A or B, and the conductivity and refractive index of the target are not judged as D. However, this does not apply when it is included in ⁇ .
  • ⁇ is the most preferable information recording medium. ⁇ is a more preferable information recording medium. ⁇ is a preferred information recording medium. X is not practical as an information recording medium.
  • Table 2 shows the results of the A-side information recording medium 101.
  • the information recording medium 100 to which the first dielectric film 11 is coated with a dielectric containing 50 mol% or more of SiC-O, SiC-N, or SiC-ON has a comprehensive evaluation of ⁇ or ⁇ , and is good for recording and reproduction. The characteristics were obtained.
  • a dielectric containing 70 mol% or more of any of SiC-O, SiC-N, and SiC-ON to the first dielectric film 11, the overall evaluation becomes ⁇ , and better recording / reproduction characteristics can be obtained. It was.
  • the B-side information recording medium 102 also contains 50 mol% or more of any of SiC-O, SiC-N, and SiC-ON in the first dielectric film 11.
  • Example 3 In this embodiment, an example of the information recording medium 100 shown in FIG. 1 will be described. The following is a method for manufacturing the information recording medium 100 of this embodiment.
  • the configuration of the A-side information recording medium 101 will be described.
  • a polycarbonate substrate (diameter 120 mm, thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention was used as the first dielectric film 11, the SiC—O was set to 11.5 nm using a target made of SiC, and the recording film in the present invention was used as the recording film 12 in the respective compositions shown in Table 3.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the intermediate separation layer 2 was first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin was cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 2 is formed.
  • the thickness of the intermediate separation layer 2 is about 25 ⁇ m.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3. Using a target consisting of (ZnO) 50 (SnO 2 ) 25 (mol%) as the first dielectric film 31 at 22 nm and substantially W 32 Cu 17 Ta 17 Zn 16 Mn 18 ⁇ O as the recording film 32, W 32 Cu 17 Ta 17 Zn 16 Mn 18- O at 34 nm, using a target consisting of substantially (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) as the second dielectric film 33. Then, (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) was formed at 20 nm in sequence by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply.
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare an A-side information recording medium 101.
  • the configuration of the B-side information recording medium 102 will be described.
  • a polycarbonate substrate (thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the direction of rotation of the spiral of the guide groove was opposite to that of the substrate 1 of the A-side information recording medium 101 described above.
  • the L0 layer 10 was formed on the substrate 1.
  • Table 3 shows the dielectric in the present invention as the first dielectric film 11, the recording film in the present invention as the recording film 12 with SiC—O of 11.5 nm using a target made of SiC (mol%), and Table 3.
  • a target consisting of 31 nm, substantially (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) as the second dielectric film 13 was used.
  • (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) was formed into a film at 8.5 nm in sequence by a sputtering method.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the method of forming the intermediate separation layer 2 is the same as that of the intermediate separation layer 2 of the A-side information recording medium 101 described above, but the rotation direction of the spiral of the guide groove is different from that of the intermediate separation layer 2 of the A-side information recording medium 101 described above. The direction was reversed. This enables simultaneous playback on both sides.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply (5 kW).
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare a B-side information recording medium 102.
  • the ultraviolet curable resin is uniformly applied to the surface of the A-side information recording medium 101 opposite to the surface on which the guide groove of the substrate 1 is provided, and the guide groove of the substrate 1 of the B-side information recording medium 102 is formed.
  • the resin was bonded to the surface opposite to the provided surface, and the resin was cured by ultraviolet rays to form a bonded layer 5 (thickness of about 35 ⁇ m).
  • the recording film 12 of the side A information recording medium 101 and the side B information recording medium 102 W 25 Cu 21 Ta 21 Zn 5 Mn 28 (atomic%) W 14 Cu 22 Ta 21 Zn15Mn 28 (atomic%) W 15 Cu 21 Ta 21 Zn 15 Mn 28 (atomic%) W 45 Cu 21 Ta 11 Mn 23 (atomic%) W 46 Cu 21 Ta 10 Mn 23 (atomic%) W 40 Cu 0 Ta 27 Zn 5 Mn 28 (atomic%) W 40 Cu 5 Ta 22 Zn 5 Mn 28 (atomic%) W 23 Cu 30 Ta 17 Mn 30 (atomic%) W 23 Cu 31 Ta 16 Mn 30 (atomic%) W 42 Cu 20 Ta 23 Zn 15 Mn 0 (atomic%) W 42 Cu 20 Ta 18 Zn 15 Mn 5 (atomic%) W 26 Cu 20 Ta 14 Mn 40 (atomic%) W 26 Cu 20 Ta 13 Mn 41 (atomic%) W 20 Cu 17 Ta 26 Zn 15 Mn 22 (atomic%) W 20 Cu 17 Ta 25 Zn 15 Mn 23 (atomic%) W 40 Cu 27 Ta 2 Mn 33 (atomic%)
  • the reproduction durability at 8 times speed was evaluated in 3-1 to 3-17.
  • the reproduction durability was evaluated using a pulse tech evaluation machine (ODU-1000).
  • the wavelength of the laser beam 6 of the evaluation machine was 405 nm, the numerical aperture NA of the objective lens was 0.91, and information was recorded in the groove and land.
  • the linear speed of recording was 18.06 m / s (500 GB-8 times speed) and the linear speed of reproduction was 18.06 m / s (500 GB-8 times speed).
  • the data bit length was 51.3 nm, and the 83.4 GB density per information layer was recorded.
  • the laser light 6 which was superposed (modulated) at a high frequency of 2: 1 was used as the reproduced light. Random signals (2T to 12T) were recorded, and the signal quality was evaluated as d-MLSE (Distribution Delivered-Maximum Likelihood Function Sequence Estimation).
  • a random signal is recorded in an isolated groove, and the random signal of the groove located in the center of the recorded track is reproduced at a reproduction power of 4.0 mW and a linear velocity of 18.06 m / s.
  • the reproduction was performed, and the quality was judged based on the amount of change in d-MLSE between the first and 1 million times of repeated reproductions.
  • the recording power at which d-MLSE is the best is defined as the recording sensitivity, and the criteria for determining the quality of the recording sensitivity of the L0 layer 10 are as follows. When the recording sensitivity was 50 mW or less, it was OK (practical), and when the recording sensitivity was greater than 50 mW, it was NG (unsuitable for practical use).
  • the quality criteria for d-MLSE of L0 layer 10 were as follows. When d-MLSE was 16.0% or less, it was OK (practical), and when it was larger than 16.0%, it was NG (unsuitable for practical use).
  • the quality criteria for DC sputtering are as follows. The case where DC sputtering can be performed is OK (practical), and the case where DC sputtering cannot be performed is NG (unsuitable for practical use).
  • ⁇ is the most preferable information recording medium. ⁇ is a more preferable information recording medium. ⁇ is a preferable information recording medium. ⁇ is a practical but unsuitable information recording medium. X is not practical as an information recording medium.
  • Table 3 shows the results of the A-side information recording medium 101.
  • the composition of the recording film 12 was such that the metal element contained in the recording film 12 was composed of the composition formula: W x Cu y Mn z M 100-x-y-z (atomic%).
  • W x Cu y Mn z M 100-x-y-z (atomic%) When written, 15 ⁇ x ⁇ 45, 0 ⁇ y ⁇ 30,
  • the B-side information recording medium 102 Similar to the results of the A-side information recording medium 101, the B-side information recording medium 102 also exhibits good reproduction durability, recording sensitivity, and d-MLSE, and DC sputtering can be performed. As a result of examining various recording film compositions, the composition of the recording film 12 was 22 ⁇ x ⁇ 35. 13 ⁇ y ⁇ 28, It was confirmed that a very preferable information recording medium can be obtained in the A-side information recording medium 101 satisfying 15 ⁇ z ⁇ 30 and 65 ⁇ x + y + z ⁇ 85.
  • the B-side information recording medium 102 Similar to the results of the A-side information recording medium 101, the B-side information recording medium 102 also exhibits good reproduction durability, recording sensitivity, and d-MLSE, and DC sputtering can be performed.
  • the composition of the recording film 12 was 22 ⁇ x ⁇ 35. 13 ⁇ y ⁇ 28, It was confirmed that a very preferable information recording medium can be obtained in the A-side information recording medium 101 satisfying 15 ⁇ z ⁇ 30 and 65 ⁇ x + y + z ⁇ 85.
  • Example 4 In this embodiment, an example of the information recording medium 100 shown in FIG. 1 will be described. The following is a method for manufacturing the information recording medium 100 of this embodiment.
  • the configuration of the A-side information recording medium 101 will be described.
  • a polycarbonate substrate (diameter 120 mm, thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention was used as the first dielectric film 11, the SiC—O was set to 11.5 nm using a target made of SiC, and the recording film in the present invention was used as the recording film 12 in the respective compositions shown in Table 4.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the intermediate separation layer 2 was first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin was cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 2 is formed.
  • the thickness of the intermediate separation layer 2 is about 25 ⁇ m.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply.
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare an A-side information recording medium 101.
  • the configuration of the B-side information recording medium 102 will be described.
  • a polycarbonate substrate (thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the direction of rotation of the spiral of the guide groove was opposite to that of the substrate 1 of the A-side information recording medium 101 described above.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention was used as the first dielectric film 11, the SiC—O was set to 11.5 nm using a target made of SiC, and the recording film in the present invention was used as the recording film 12 in the respective compositions shown in Table 4.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the method of forming the intermediate separation layer 2 is the same as that of the intermediate separation layer 2 of the A-side information recording medium 101 described above, but the rotation direction of the spiral of the guide groove is different from that of the intermediate separation layer 2 of the A-side information recording medium 101 described above. The direction was reversed. This enables simultaneous playback on both sides.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply (5 kW).
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare a B-side information recording medium 102.
  • the ultraviolet curable resin is uniformly applied to the surface of the A-side information recording medium 101 opposite to the surface on which the guide groove of the substrate 1 is provided, and the guide groove of the substrate 1 of the B-side information recording medium 102 is formed.
  • the resin was bonded to the surface opposite to the provided surface, and the resin was cured by ultraviolet rays to form a bonded layer 5 (thickness of about 35 ⁇ m).
  • the recording film 12 of the side A information recording medium 101 and the side B information recording medium 102 W 25 Cu 21 Ta 21 Zn 5 Mn 28 (atomic%) W 25 Cu 21 Nb 21 Zn 5 Mn 28 (atomic%) W 25 Cu 21 Mo 21 Zn 5 Mn 28 (atomic%) W 25 Cu 21 Ti 21 Zn 5 Mn 28 (atomic%)
  • the information recording medium 100 to which the above was applied was produced.
  • the refractive index of the recording film 12 was measured with an ellipsometer, and the quality was judged according to the following criteria.
  • the refractive index of the recording film 12 is A (very good) for 2.2 or more, B (good) for 2.0 or more and less than 2.2, C (practical level) for 1.8 or more and less than 2.0, and 1. Less than 0.8 was defined as D (impractical).
  • Table 4 shows the results of the A-side information recording medium 101.
  • the refractive index of the recording film 12 is 2.2 or more and the effective reflectance is 3.2% or more.
  • Example 5 In this embodiment, an example of the information recording medium 100 shown in FIG. 1 will be described. The following is a method for manufacturing the information recording medium 100 of this embodiment.
  • the configuration of the A-side information recording medium 101 will be described.
  • a polycarbonate substrate (diameter 120 mm, thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention was used as the first dielectric film 11, the SiC—O was set to 11.5 nm using a target made of SiC, and the recording film in the present invention was used as the recording film 12 in the respective compositions shown in Table 5.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the intermediate separation layer 2 was first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin was cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 2 is formed.
  • the thickness of the intermediate separation layer 2 is about 25 ⁇ m.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sccm) using a pulse DC power supply.
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare an A-side information recording medium 101.
  • the configuration of the B-side information recording medium 102 will be described.
  • a polycarbonate substrate (thickness 0.5 mm) having a spiral guide groove (depth 29 nm, track pitch (land-groove distance) 0.225 ⁇ m) was prepared.
  • the direction of rotation of the spiral of the guide groove was opposite to that of the substrate 1 of the A-side information recording medium 101 described above.
  • the L0 layer 10 was formed on the substrate 1.
  • the dielectric in the present invention was used as the first dielectric film 11, the SiC—O was set to 11.5 nm using a target made of SiC, and the recording film in the present invention was used as the recording film 12 in the respective compositions shown in Table 5.
  • the film formation of the first dielectric film 11 was carried out in an Ar + O 2 atmosphere (flow rate: 12 + 20 sccm) using a DC power supply (1 kW).
  • the film formation of the recording film 12 was performed using a pulse DC power supply (5 kW) in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 30 sccm).
  • the film formation of the second dielectric film 13 was carried out in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 2 having a spiral guide groove (depth 28 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L0 layer 10.
  • the method of forming the intermediate separation layer 2 is the same as that of the intermediate separation layer 2 of the A-side information recording medium 101 described above, but the rotation direction of the spiral of the guide groove is different from that of the intermediate separation layer 2 of the A-side information recording medium 101 described above. The direction was reversed. This enables simultaneous playback on both sides.
  • the L1 layer 20 was formed on the intermediate separation layer 2.
  • (ZrO 2 ) 25 (ZnO) 50 (SnO 2 ) 25 (mol%) is 22 nm
  • substantially W 31 Cu 18 in the embodiment of the present invention Using a target consisting of Ta 16 Zn 16 Mn 19- O, W 31 Cu 18 Ta 16 Zn 16 Mn 19- O was substantially (ZrO 2 ) 25 (SiO 2 ) 25 as a second dielectric film 23 at 36 nm.
  • the first dielectric film 21 was formed in an Ar atmosphere (flow rate: 12 sccm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 22 was performed using a pulse DC power supply (5 kW) in an atmosphere of a mixed gas of Ar + O 2 (flow rate: 12 + 36 sccm).
  • the film formation of the second dielectric film 23 was performed in an Ar atmosphere (flow rate: 12 sccm) using a DC power supply (2 kW).
  • an intermediate separation layer 3 having a spiral guide groove (depth 26 nm, track pitch (land-groove distance) 0.225 ⁇ m) was formed on the L1 layer 20.
  • the intermediate separation layer 3 is first spin-coated with an ultraviolet curable resin that forms the thickness of the mother body, and then the resin is cured by ultraviolet rays.
  • the ultraviolet curable resin that transfers the guide groove is spin-coated, a stamper substrate made of polycarbonate having the guide groove formed is attached thereto, the resin is cured by ultraviolet rays, and then the stamper substrate is peeled off.
  • the intermediate separation layer 3 was formed.
  • the thickness of the intermediate separation layer 3 is about 18 ⁇ m.
  • the L2 layer 30 was formed on the intermediate separation layer 3.
  • a target consisting of (ZrO 2 ) 25 (SiO 2 ) 25 (In 2 O 3 ) 50 (mol%) 20 nm was sequentially formed by a sputtering method.
  • the film formation of the first dielectric film 31 was performed in an Ar atmosphere (flow rate: 12 sCCm) using a pulse DC power supply (3 kW).
  • the film formation of the recording film 32 was performed in a mixed gas atmosphere of Ar + O 2 (flow rate: 12 + 36 sCCm) using a pulse DC power supply (5 kW).
  • the film formation of the second dielectric film 33 was performed in an Ar atmosphere (flow rate: 12 sCCm) using a pulse DC power supply (2 kW).
  • an ultraviolet curable resin was applied onto the second dielectric film 33, spin-coated, and then the resin was cured by ultraviolet rays to form a cover layer 4 of about 57 ⁇ m to prepare a B-side information recording medium 102.
  • the ultraviolet curable resin is uniformly applied to the surface of the A-side information recording medium 101 opposite to the surface on which the guide groove of the substrate 1 is provided, and the guide groove of the substrate 1 of the B-side information recording medium 102 is formed.
  • the resin was bonded to the surface opposite to the provided surface, and the resin was cured by ultraviolet rays to form a bonded layer 5 (thickness of about 35 ⁇ m).
  • the recording material located on the back side of the recording film 12 of the side A information recording medium 101 and the side B information recording medium 102 with respect to laser irradiation is described.
  • the amount of change is defined as ⁇ d-MLSE, 1.0% or less is A (very good), greater than 1.0% and 2.0% or less is B (good), and more than 2.0%.
  • a value of 3.0% or less was defined as C (practical level), and a value greater than 3.0% was defined as D not practical).
  • the recording sensitivity of the groove and land of the L0 layer 10 was evaluated.
  • Table 5 shows the results of the reproduction durability of the A-side information recording medium 101.
  • a laminated film is formed by changing the film thickness ratio of two types of recording materials having different compositions, W 32 Cu 17 Ta 22 Zn 11 Mn 18 (atomic%) and W 25 Cu 21 Ta 21 Zn 5 Mn 28 (atomic%). It was shown that the recording sensitivity of the L0 layer 10 can be adjusted by doing so.
  • the dielectric film material of the present disclosure can be used not only in the L0 layer but also in the L1 layer and the L2 layer.
  • the information recording medium and the manufacturing method thereof of the present disclosure have an information layer having better reproduction durability characteristics, they are suitable for recording information at a high recording density and are useful for an optical disk for recording a large amount of contents. .. Specifically, it is useful for next-generation optical discs (for example, a recording capacity of 500 GB) having three or four layers of information layers on both sides according to the archival disk standard. Further, it is also useful for a large-capacity next-generation optical disc (for example, a recording capacity of 1 TB) using a multi-value recording method.
  • next-generation optical discs for example, a recording capacity of 500 GB
  • a large-capacity next-generation optical disc for example, a recording capacity of 1 TB

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  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Optical Record Carriers And Manufacture Thereof (AREA)
  • Manufacturing Optical Record Carriers (AREA)
PCT/JP2019/051040 2019-05-15 2019-12-25 情報記録媒体とその製造方法 WO2020230357A1 (ja)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006035618A (ja) * 2004-07-27 2006-02-09 Ricoh Co Ltd 光情報記録媒体およびその製造方法
JP2006092660A (ja) * 2004-09-24 2006-04-06 Pioneer Electronic Corp 情報記録媒体
JP2006252766A (ja) * 2006-05-15 2006-09-21 Toshiba Corp 相変化光記録媒体
JP2008097749A (ja) * 2006-10-13 2008-04-24 Canon Inc 追記型光記録媒体
WO2018155070A1 (ja) * 2017-02-24 2018-08-30 パナソニックＩｐマネジメント株式会社 情報記録媒体とその製造方法、およびスパッタリングターゲット

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006035618A (ja) * 2004-07-27 2006-02-09 Ricoh Co Ltd 光情報記録媒体およびその製造方法
JP2006092660A (ja) * 2004-09-24 2006-04-06 Pioneer Electronic Corp 情報記録媒体
JP2006252766A (ja) * 2006-05-15 2006-09-21 Toshiba Corp 相変化光記録媒体
JP2008097749A (ja) * 2006-10-13 2008-04-24 Canon Inc 追記型光記録媒体
WO2018155070A1 (ja) * 2017-02-24 2018-08-30 パナソニックＩｐマネジメント株式会社 情報記録媒体とその製造方法、およびスパッタリングターゲット

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