JP2005093027A - Recording medium and recording method of optical data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phase-change optical data recording medium which performs large-capacity recording, and has compatibility with DVD. <P>SOLUTION: In an optical data recording medium, at least a reflection layer, a first dielectric layer, recording layer, and a second dielectric layer are provided in this order on a first substrate, in addition, light is injected for recording from the side of a second substrate provided via a resin layer, thickness of the first substrate is equal to that of the second substrate, a concentric or spiral groove is provided on a surface for deposition of the first substrate but not provided on the second substrate at a light injection side, and reflectivity at a wavelength in an unrecorded blue-region is controlled to be 8 to 25%. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical information recording medium and a recording method, and more particularly, recording, reproduction, and erasing can be performed by causing a recording layer to produce a crystal-amorphous phase change by an irradiated laser. The present invention relates to a phase change type optical information recording medium excellent in large capacity.

  As an optical information recording medium capable of recording, reproducing and erasing information by laser beam irradiation, a phase change type optical information recording medium using a reversible phase change between a crystalline state and an amorphous state is known. . At present, DVD-RAM, DVD-RW, and DVD + RW, which record a capacity of 4.7 GB on a 5-inch disk, have been put into practical use.

A phase change recording medium currently in practical use includes a lower dielectric layer (first dielectric layer), a phase change recording layer, and an upper dielectric layer on a polycarbonate substrate (hereinafter referred to as a PC substrate) having spiral or concentric grooves. In this structure, the body layer (second dielectric layer) and the reflective layer are laminated in this order. When Ag or an Ag alloy is used for the reflective layer, the upper dielectric layer may be formed in two layers. What is put into practical use as a dielectric material is a mixture of ZnS and SO ₂ , and the mixing ratio is ZnS: SiO 2 = 8: 2 in terms of molar ratio. As recording materials, a material in which impurities are added with Ge—Sb—Te as a main component and a material in which impurities are added with Sb—Te as a main component have been put into practical use.
Further, the maximum recording capacity of a repetitively recordable recording medium that is currently in practical use is 4.7 GB for a 120 mm disk, and is widely used as a DVD + RW, DVD-RW, or DVD-RAM standard.

  When performing high-quality video recording, the recording capacity of 4.7 GB is insufficient, and an increase in capacity is desired. In order to increase the recording capacity of the optical information recording medium, there are methods such as enlargement of the objective lens diameter (hereinafter referred to as NA), shortening of the recording wavelength, or multi-value recording.

  Currently, a standard for recording at a wavelength of 405 nm and NA of 0.85 and recording about 25 GB on a 120 mm disk and a standard for recording at a wavelength of 405 nm and NA of 0.65 and recording about 20 GB on a 120 mm disk have been proposed.

  In the standard of the wavelength of 405 nm and NA of 0.85, the recording capacity can be increased, but the thickness uniformity of the light transmission layer becomes extremely severe. For example, in Japanese Patent Laid-Open No. 10-326435 (Patent Document 1), an LD having a wavelength of 405 nm and an objective lens having an NA of 0.85 are used to increase the recording capacity, and a reflective layer is formed on a first substrate having a groove. Recording is performed by allowing recording / reproducing light to enter the optical recording medium provided with the lower dielectric layer, the recording layer, the upper dielectric layer, and the second substrate from the second substrate side. Here, the thickness uniformity specification is relaxed by setting the thickness of the light transmission layer (second substrate) to 3 μm to 177 μm. However, this is less than 1/3 of the light transmission layer thickness of DVD, and the reliability with respect to fingerprints and scratches on the surface tends to be extremely deteriorated.

  On the other hand, when recording at a wavelength of 405 nm and NA of 0.65, the light transmission layer can be set to 0.6 mm, which is the same as DVD, but inferior to the case of NA of 0.85 in terms of recording capacity. When recording at a wavelength of 405 nm and NA of 0.65, for example, multi-value recording as described in Japanese Patent Application Laid-Open No. 2001-84591 (Patent Document 2) is 1.5 times as compared with conventional binary recording. Expected capacity increase. However, in multi-level recording, it is necessary to form a finer amorphous mark than in conventional binary recording, and thus there is a problem that the thickness of the light transmission layer and the physical property margin such as birefringence are reduced.

JP-A-10-326435 JP 2001-84591 A

  An object of the present invention is to enable high-density recording equivalent to NA 0.85 recording even in NA 0.65 recording with high compatibility with DVD and good reliability, and the recording margin, particularly the repeated recording margin is expanded. An optical recording medium and a recording method using the optical recording medium are provided.

  The said subject is achieved by following (1)-(12).

(1) A second layer having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on a first substrate, and further having a resin layer interposed therebetween. In an optical information recording medium in which recording is performed with light incident from the substrate side, the first substrate and the second substrate have the same thickness, and are formed concentrically or spirally on the film formation surface of the first substrate. The second substrate on the light incident side has a groove, and is adjusted so that the reflectance in the wavelength of the blue region in an unrecorded state is 8% or more and 25% or less without the groove. A characteristic optical information recording medium.

(2) A second layer having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on a first substrate, and further having a resin layer interposed therebetween. In an optical information recording medium in which recording is performed with light incident from the substrate side, the first substrate and the second substrate have the same thickness, and are formed concentrically or spirally on the film formation surface of the first substrate. An optical information recording medium having a groove, wherein the second substrate on the light incident side has no groove, and is further adjusted to have a modulation factor of 50% or more at a wavelength in a blue region. .

(3) The optical information recording medium as described in (1) or (2) above, wherein the thickness of the substrate is 0.6 mm ± 0.1 mm.

(4) The recording layer is mainly composed of Sb and Te, Sb atomic% is larger than Te atomic%, and In, Ag, Ge, Ga, Sn, Zn, Pd, Pt, Si, Cu, Au, Pb, Bi And containing at least one element selected from the group consisting of Cr, Co, O, S, N, Se, Ti, Ta, Nb, V, Zr, Hf and rare earth metals as impurities ( The optical information recording medium according to any one of 1) to (3).

(5) The optical information recording medium as described in (4) above, wherein the recording layer contains Sb and Te as main components and contains 10 atomic% or less of Ge.

(6) In the above (4), the recording layer contains Sb and Te as main components and contains 10 atomic% or less of Ge and at least one selected from In, Ga, Mn, and Sn. The optical information recording medium described.

(7) Any of the above (1) to (6), wherein the second dielectric layer contains at least a mixture of ZnS and SiO _{2 and} the ZnS molar ratio in the mixture is 40% or more and 80% or less. An optical information recording medium according to claim 1.

(8) A recording method, wherein an amorphous material having a length in the scanning beam scanning direction of less than 0.26 μm is formed on the optical information recording medium according to any one of (1) to (7).

(9) A recording method, wherein recording is performed on the optical information recording medium according to any one of (1) to (7) by controlling the amorphous area in three or more stages.

(10) The recording method as described in (8) or (9) above, wherein the laser light irradiation pulse width is 5 nanoseconds or less when the amorphous is formed by irradiating the laser light in a pulse form.

(11) The recording method according to any one of (8) to (10), wherein the amorphous area is changed by changing the cooling time with the same laser beam irradiation pulse width.

(12) The recording method according to any one of (8) to (11), wherein recording is performed with a combination of a laser having a wavelength of 405 nm and an NA 0.65 objective lens.

  In claim 1, on the first substrate, the second substrate having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the order, and further having a resin layer interposed therebetween. In an optical information recording medium for recording by entering light from the side, the first substrate and the second substrate have the same thickness, and concentric or spiral grooves on the film formation surface of the first substrate And the second substrate on the light incident side has no groove, and is further adjusted so that the reflectance in the wavelength of the blue region in an unrecorded state is 8% or more and 25% or less. Therefore, during recording, the substrate having a groove is not damaged by heat, and the repeated recording characteristics are good.

  According to a second aspect of the present invention, at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer are provided on the first substrate in this order, and further from the second substrate side having a resin layer interposed therebetween. In an optical information recording medium that performs recording upon incidence of light, the first substrate and the second substrate have the same thickness, and the film formation surface of the first substrate has concentric or spiral grooves. In addition, the second substrate on the light incident side is characterized by being adjusted so that the modulation degree in the wavelength of the blue region is 50% or more without having a groove. The substrate having the grooves is not damaged by heat, and the repeated recording characteristics are good.

  In claim 3, since the thickness of the substrate is 0.6 mm ± 0.1 mm in claim 1 or 2, the substrate thickness is scratched as compared with a thickness of less than 0.3 mm. The reliability with respect to etc. is good.

  In claim 4, the main components of the recording layer according to claims 1 to 3 are Sb and Te, the Sb atomic% is larger than the Te atomic%, and In, Ag, Ge, Ga, Sn, Zn, Pd, At least one element selected from the group consisting of Pt, Si, Cu, Au, Pb, Bi, Cr, Co, O, S, N, Se, Ti, Ta, Nb, V, Zr, Hf, and rare earth metals. Since it is characterized by containing it as an impurity, it is possible to perform melt erasure in direct overwrite, and high-density recording with a large margin is possible.

  In claim 5, the recording layer according to claim 4 is characterized by containing 10 atomic% or less of Ge, so that the reproduction light resistance can be increased and the reproduction light intensity can be increased. Become.

  Since the recording layer according to claim 6 is characterized in that the recording layer contains 10 atomic% or less of Ge and at least one selected from In, Ga, Mn, and Sn. It is possible to combine recording characteristics such as speed.

In Claim 7, in Claims 1 to 6, the second dielectric layer further contains at least ZnS and SiO ₂ , and the ZnS molar ratio is 40% or more and 80% or less. Good heat dissipation characteristics, especially good initial recording characteristics.

  According to the eighth aspect of the present invention, the optical information recording medium according to any one of the first to seventh aspects is characterized in that an amorphous material having a length in the recording beam scanning direction of less than 0.26 μm is formed. Density recording is possible.

  According to the ninth aspect of the present invention, in the optical information recording medium of the first to eighth aspects, the recording is performed by further controlling the amorphous area in three or more stages. Can be recorded at high density.

  In the tenth aspect of the present invention, since the amorphous structure is formed by further irradiating the laser beam in a pulse shape in the eighth to ninth aspects, and the laser beam irradiation pulse width is 5 nanoseconds or less, there is little cross erase. .

  In claim 11, since the laser light irradiation pulse width is made the same as in claims 8 to 10 and the amorphous area is changed by changing the cooling time, the cross erase is small and good. SDR is obtained.

  The twelfth aspect of the present invention is characterized in that the laser beam having a wavelength of 405 nm and the NA 0.65 objective lens are combined in the eighth to eleventh aspects, so that compatibility with a currently popular DVD is easy.

The present invention is described in further detail below.
According to the present invention, there is provided a second substrate having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on a first substrate, and further having a resin layer interposed therebetween. In the phase change optical information recording medium for recording by entering light from the substrate side, the first substrate and the second substrate have the same thickness, and are formed concentrically on the film formation surface of the first substrate. It has a spiral groove, and the second substrate on the light incident side has no groove, and is further adjusted so that the reflectance in the wavelength of the blue region in an unrecorded state is 8% or more and 25% or less. It is characterized by being.

The thickness of the first substrate and the second substrate may be adjusted differently due to manufacturing process errors or adjustment of recording characteristics. The thickness difference is preferably 0.1 mm or less, and more preferably Is 0.05 mm or less.
For example, the reflectance is measured by using a pulsed DDU1000 having a pickup head equipped with a laser diode having a wavelength of 405 nm, and a reflection voltage value of an Ag disk having a known reflectance formed on a glass substrate and an unrecorded value. It can be measured by comparing the reflected voltage of the phase change recording medium in the state.

  According to the present invention, there is provided a first substrate having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on a first substrate, and further having a resin layer interposed therebetween. In the phase change optical information recording medium in which recording is performed with light incident from the side of the second substrate, the thicknesses of the first substrate and the second substrate are the same, and concentric circles are formed on the film formation surface of the first substrate. Or a spiral groove, and the second substrate on the light incident side has no groove, and is further adjusted to have a modulation factor of 50% or more in the wavelength of the blue region. To do.

  Similar to the above example, the thicknesses of the first substrate and the second substrate may vary due to manufacturing process errors or adjustment of recording characteristics. The thickness difference is preferably It is 0.1 mm or less, more desirably 0.05 mm or less.

  The degree of modulation is a value obtained by dividing the difference in reflectance between the crystalline state and the amorphous state by the larger reflectance value of the crystalline state or the amorphous state.

  In the present invention, the first substrate has a spiral or concentric groove. The groove may meander or be interrupted for address information or the like.

Sb and Te as the main components of the phase change recording layer of the present invention are, for example, that Sb and Te maintain a metastable Sb ₃ Te phase, and the recording material of the recording layer is changed into an amorphous phase-crystalline phase by a recording operation. It means that the quantity ratio that can be converted is maintained. Although it is characterized by containing impurities as subcomponents, the total amount of impurity elements is preferably less than 10 atomic% so as not to prevent the appearance of the metastable Sb ₃ Te phase.

  The phase change optical information recording medium according to the present invention preferably contains Ge in the recording layer containing Sb and Te as main components. Ge increases the activation energy when the recording layer undergoes a solid phase transition from amorphous to crystal, and thus has the effect of increasing the storage reliability of the amorphous mark and improving the resistance to amorphous crystallization during reproduction. is there. The preferred concentration of Ge in the recording layer is 2 to 10 atomic%, more preferably 3 to 6 atomic%.

  The impurities added to the recording layer include elements belonging to Groups I and VII of the periodic table, such as Ag, B, Ca, Cd, for the purpose of adjusting the crystallization speed, recording characteristics, and storage characteristics. Ce, Co, Cr, Cu, Fe, Ga, Ge, H, Hg, Ir, In, K, La, Li, Mg, Mn, Mo, Na, Ni, O, P, Pb, Pd, Po, Pr, Elements such as Pt, Pu, Rb, Rh, Ru, S, Se, Si, Sn, Sr, Th, Ti, Tl, U, Cl, and Br can be included.

Subsequently, the thin film formed on the first substrate will be described in order.
As the reflective layer in the present invention, metals such as Al, Au, Cu, Ag, Cr, Sn, Zn, In, Pd, Zr, Fe, Co, Ni, Si, Ge, Sb, Ta, W, Ti, and Pb are used. A simple substance or an alloy mainly composed of

  It is important for this layer to dissipate heat efficiently, and the film thickness is preferably 50 to 180 nm. If the film thickness is too thick, the heat dissipation efficiency is too high and the sensitivity becomes poor. If the film thickness is too thin, the sensitivity is good, but repeated overwrite characteristics deteriorate. The properties are required to have high thermal conductivity, high melting point, and good adhesion to the protective layer material.

In the present invention, the first dielectric _{layer, SiOx, ZnO, SnO 2,} Al 2 O 3, TiO 2, In 2 O 3, MgO, ZrO 2, Ta 2 O metal oxide such as _{5, Si} 3 _{N 4} , AlN, TiN, BN, nitrides such as ZrN, ZnS, a sulfide such as _{TaS 4, SiC, TaC, B4C} , WC, TiC, include carbides such as ZrC. The first dielectric layer may be multilayered to adjust thermal characteristics.

  The film thickness of the first dielectric layer is preferably 5 to 50 nm. When the thickness of the dielectric layer is less than 5 nm, the recording sensitivity is lowered. On the other hand, if it exceeds 50 nm, the overwrite characteristics are repeatedly deteriorated due to a decrease in heat dissipation.

  The recording layer may have a crystallization promoting layer in order to promote crystallization. Examples of the material of the crystallization promoting layer include Bi simple substance and Bi compound, Sb simple substance and Sb compound, and metal silicide such as TiSix and Wsix. And carbides such as SiC.

In the present invention, it is preferable that the second dielectric layer material contains ZnS and SiO ₂ and the molar ratio of ZnS is 40% or more and 80% or less. For the second dielectric layer material, less than 20 mol% of metal oxide such as ZnO, SnO ₂ , Al ₂ O ₃ , TiO ₂ , In ₂ O ₃ , MgO, ZrO ₂ , Ta ₂ O ₅ , Si ₃ N ₄ , nitrides such as AlN, TiN, BN, and ZrN, sulfides such as ZnS and TaS ₄ , and carbides such as SiC, TaC, B ₄ C, WC, TiC, and ZrC may be added.

  By adding these materials, optical characteristics and the like are finely adjusted. The thickness of the second dielectric layer is preferably in the range of 30 to 200 nm. If it is less than 30 nm, the environmental resistance protection function is lowered, the heat resistance is lowered, and the livestock heat effect is lowered. If it exceeds 200 nm, it is not preferable because film peeling or cracking occurs due to an increase in film temperature or a decrease in recording sensitivity of the media occurs in a film forming process such as sputtering.

  The recording method of the present invention is characterized in that an amorphous film having a thickness of less than 0.26 μm is formed in the beam scanning direction on the recording medium. Further, it is characterized in that the amorphous is formed by controlling in three or more stages with a length of less than 0.26 μm in the beam scanning direction. That is, high-density recording is realized by recording multilevel information.

  An example of a recording laser modulation method used in the recording method of the present invention is schematically shown in FIG. In the multi-value recording method according to the present invention, the recording mark recording area is divided into equal areas (hereinafter, this divided area is referred to as a cell). The physical size of the cell 10 is determined by the linear velocity and the cell frequency at the time of recording. The cell frequency is the reciprocal of the cell period 11 and takes an integral multiple of the reference clock.

  For example, if the cell frequency is 40 ns, the cell frequency is 25 MHz, and the cell length when the recording linear velocity is 6.5 m / s is 0.26 μm. The recording laser is modulated by setting the respective powers of the recording pulse 12, the bottom pulse 13, and the erasing pulse 14, and the rising times 15, 16, and 17, respectively. The multi-value recording mark 18 is formed by such laser modulation.

Reference numeral 19 schematically represents a reproducing laser beam. The spot diameter of the laser beam referred to here is the converging diameter of the laser, and is estimated to be φD = 0.82 × λ / NA when a laser beam having a wavelength λ and a focus lens having a numerical aperture NA are used. This is the diameter at which the intensity of the laser beam is 1 / e ^{2. When} λ = 405 nm and NA = 0.65, φD = 0.51 μm.

  The multi-value information is recorded as a ratio occupied by the multi-value recording mark 18 with respect to the cell, and when the reproduction laser beam 19 is scanned along the groove by the relative movement with the recording medium, the reflection of the RF signal is performed. It is read as a rate fluctuation. That is, the recording mark is obtained so that the reflectance level can be obtained in multiple stages of 3 to 8 with the difference in reflectance between the case where the cell 10 is entirely the crystal portion 20 and the case where the largest recording mark is formed as the signal dynamic range. Is controlled so as to correspond to multi-value information.

  The recording method according to the present invention is characterized in that {(time 16) − (time 15)} in FIG. 1, that is, the laser light irradiation pulse width is 5 nanoseconds or less. It has been confirmed that by controlling the laser light irradiation pulse to 5 nanoseconds or less, it is possible to form an amorphous film having a length controlled in seven stages or more in a 0.26 μm cell. The minimum amorphous length is less than 0.05 μm. By such recording, recording equivalent to 22 GB can be performed on a CD-sized disc.

  Hereinafter, the present invention will be described more specifically with reference to examples.

(Examples 1-3)
A polycarbonate (hereinafter, PC) substrate having a thickness of 0.6 mm is formed as the first substrate by an injection molding method. A spiral groove having a pitch of 0.46 μm and a groove width of 0.2 μm is transferred and formed on the polycarbonate substrate.

A thin film is formed on the surface of the PC substrate having the grooves by magnetron sputtering in the following order to form an information base.
Material (film thickness)
(1) Reflective heat dissipation layer Ag (140 nm)
(2) First dielectric layer ZnS · SiO ₂ (mol ratio: 79.5: 20.5)
(14 nm)
(3) Recording layer See Table 1 (14 nm)
(4) Second dielectric layer ZnS · SiO ₂ (ZnS molar ratio 70%)
(50nm)

  A 10 μm ultraviolet curable resin is spin-coated on the second dielectric layer and is bonded to a second substrate having no groove. As the second substrate, a polycarbonate substrate having a thickness of 0.6 mm formed by an injection molding method is used. Here, since the surface of the light incident side is irrelevant to recording / reproduction, there is no problem even if the second substrate has a groove. FIG. 2 shows a cross-sectional structure.

(Comparative Example 1)
A polycarbonate (hereinafter, PC) substrate having a thickness of 0.6 mm is formed as the first substrate by an injection molding method. A spiral groove having a pitch of 0.46 μm and a groove width of 0.2 μm is transferred and formed on the polycarbonate substrate.

A thin film is formed on the surface of the PC substrate having the grooves by the magnetron sputtering method in the following order to form an information base. Material (film thickness)
(1) First dielectric layer: ZnS · SiO ₂ (ZnS molar ratio 70%) (50 nm)
(2) Recording layer: Ge ₅ Sb ₇₅ Te ₂₀ (14 nm)
(3) Second dielectric layer: ZnS.SiO ₂ (molar ratio 79.5: 20.5) (14 nm)
(4) Reflective heat dissipation layer: Ag (140 nm)
A 10 μm ultraviolet curable resin is spin-coated on the reflective heat radiation layer and is pressure-bonded to the second substrate. As the second substrate, a polycarbonate substrate having a thickness of 0.6 mm formed by an injection molding method is used. FIG. 2 shows a cross-sectional structure.

  The recording medium manufactured above uses a semiconductor laser with a wavelength of 405 nm and a pickup of NA 0.65, recording power = 10 mW, recording linear velocity = 6.0 m / s, channel clock frequency T = 74.3 MHz, and EFM modulation. The recorded signals of 3T to 14T were repeatedly recorded, and the number of times until the jitter increased by 1% with respect to the initial recording was examined.

  Here, the jitter is a value (unit%) obtained by dividing the standard deviation of the reading time deviation between the boundary between the recording mark and the space by the reading clock one cycle time T. For example, in the recording DVD standard, it is usually 9 % Or less. The recording capacity in this case is equivalent to 12 GB in CD size.

  Further, the number of recordings in which the SDR was increased by 0.3% with respect to the initial recording when the amorphous area of less than 0.26 μm was controlled in 7 steps in the recording beam scanning direction was examined.

  As described above, recording is performed by controlling the amorphous area in seven steps, so that eight-value recording including the reflectance of the crystal is achieved. Even when the recording beam size is the same, it is compared with binary EFM modulation recording. Thus, the recording capacity can be at least 1.5 times. Here, SDR (sigma to dynamic range) is a value obtained by dividing the standard deviation of the reflectivity at each stage by the difference between the maximum reflectivity level and the minimum reflectivity level, and when the SDR is approximately 3% or less. This is the error rate that can be corrected. The recording capacity in the above case is equivalent to 22 GB in CD size. Table 2 shows the recording pulse width and the erasing pulse width when the amorphous area of less than 0.26 μm is controlled in seven stages.

The results in Comparative Examples and Examples are shown in Table 3.

  In the first to third embodiments, the overwrite characteristics are dramatically improved. Furthermore, the SDR is less than 3%, and multilevel recording is possible.

  The optical information recording medium of the present invention can also be used as an external memory of a PC and a video recording medium.

It is a figure for demonstrating the modulation method of the recording laser used for the recording method of this invention. It is a figure showing the layer structure of the optical information recording medium of this invention. 6 is a diagram illustrating a layer configuration of an optical information recording medium of Comparative Example 1. FIG.

Explanation of symbols

10 cell 11 cell cycle 12 recording pulse 13 bottom pulse 14 erasing pulse 15, 16, 17 rise time 18 multi-value recording mark 19 beam for reproduction 20 crystal part

Claims (12)

  From the second substrate side having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on the first substrate, and further having a resin layer interposed therebetween. In an optical information recording medium that performs recording upon incidence of light, the first substrate and the second substrate have the same thickness, and the film formation surface of the first substrate has concentric or spiral grooves. The second substrate on the light incident side has no groove, and is further adjusted so that the reflectance at the wavelength of the blue region in an unrecorded state is 8% or more and 25% or less. Optical information recording medium.   From the second substrate side having at least a reflective layer, a first dielectric layer, a recording layer, and a second dielectric layer in the above order on the first substrate, and further having a resin layer interposed therebetween. In an optical information recording medium that performs recording upon incidence of light, the first substrate and the second substrate have the same thickness, and the film formation surface of the first substrate has concentric or spiral grooves. An optical information recording medium characterized in that the second substrate on the light incident side has no groove and is further adjusted to have a modulation factor of 50% or more at a wavelength in the blue region.   3. The optical information recording medium according to claim 1, wherein the thickness of the substrate is 0.6 mm ± 0.1 mm.   The recording layer is mainly composed of Sb and Te, Sb atomic% is larger than Te atomic%, In, Ag, Ge, Ga, Sn, Zn, Pd, Pt, Si, Cu, Au, Pb, Bi, Cr, 4. At least one element selected from the group consisting of Co, O, S, N, Se, Ti, Ta, Nb, V, Zr, Hf and rare earth metals is contained as an impurity. The optical information recording medium according to any one of the above.   5. The optical information recording medium according to claim 4, wherein the recording layer contains Sb and Te as main components and contains 10 atomic% or less of Ge.   5. The optical information according to claim 4, wherein the recording layer contains Sb and Te as main components, and contains 10 atomic% or less of Ge and at least one selected from In, Ga, Mn, and Sn. recoding media. The optical information according to claim 1, wherein the second dielectric layer contains at least a mixture of ZnS and SiO ₂ , and a ZnS molar ratio in the mixture is 40% or more and 80% or less. recoding media.   A recording method, wherein an amorphous material having a length in the recording beam scanning direction of less than 0.26 μm is formed on the optical information recording medium according to claim 1.   A recording method comprising: recording on the optical information recording medium according to claim 1 by controlling an amorphous area in three or more stages.   10. The recording method according to claim 8, wherein the laser light irradiation pulse width is 5 nanoseconds or less when the amorphous is formed by irradiating the laser light in a pulse form.   The recording method according to claim 8, wherein the amorphous area is changed by changing the cooling time with the same laser beam irradiation pulse width.   The recording method according to claim 8, wherein recording is performed by a combination of a laser having a wavelength of 405 nm and an NA 0.65 objective lens.

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