JPS6273438A - Optical information recording member - Google Patents

Abstract

PURPOSE:To obtain the titled member having excellent resistance to heat and humidity and wherein a film is not broken even when recording and erasing are repeated by forming the thin film wherein the ratio in the number of atoms of the essential components, Te, Ge and Se, and the concn. of Sb are specified. CONSTITUTION:The recording layer is composed of a Te-Ge-Se-Sb composition, the ratio in the number of atoms of Te, Ge and Se are regulated within the region connecting points A1, B1, C1, D1 and E1 in the figure and the layer is composed of a material wherein the concn. of Sb is regulated to 15-40at%. Namely, Sb is added to the Te-Ge-Se system having a high crystallization transition temp. to fix an excess of Te. Sb forms a compd. (Sb2Te3) with Te. The m.p. of the (Sb2Te3) is at 622 deg.C at the highest in the Sb-Te system contg. >=50% Te. The m.p. is lower than those of Te-Ge and Te-Sn by about 150 deg.C. Accordingly, the addition of Sb enables the fixation of an excess of Te without raising the m.p. of the film with Te as the base material.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical information recording member capable of recording, erasing, and reproducing information at high speed and with high density using light, heat, or the like.

Conventional technology In recent years, the amount of information has increased and recording and playback speeds have become faster.

As density increases, optical discs that utilize laser beams are attracting attention. There are two types of original discs: write-once discs that can be recorded only once, and rewritable discs that can be used many times by erasing recorded signals. Some write-once optical discs reproduce recorded signals in a perforated state, and others reproduce them by generating unevenness. Attempts have been made to use chalcogenides as rewritable materials, and examples are known in which, starting with Te-Gef, Mug, S, Si, Se, Sb, and Bi are all added thereto.

In contrast, the present inventors previously proposed a method in which a change in reflectance due to a phase transition of a system containing an oxide such as To--TeO□ is used as a signal. Furthermore, various additives (S n , G' rBi, In,
Examples include Pb, T, j, Se, etc.). These recording members are characterized by a high C/N ratio and excellent moisture resistance.

Problems to be Solved by the Invention Rewritable information recording members made of chalcogenides are generally characterized by poor stability against repeated recording and erasing. The reason for this is thought to be that when Te, Ge and other additive components are repeated several times, phase separation occurs in the membrane, and the constituent components of the membrane are different at the initial stage and after the repetition. When utilizing phase transition in an erasable optical disc, a method is usually used in which the unrecorded and erased state is crystalline and the recorded state is amorphous. In this case, recording is done using a laser beam, which melts the film and then rapidly cools it to make it amorphous. However, current semiconductor lasers have power limitations, and a film with as low a melting point as possible has the highest recording sensitivity. Therefore, in order to improve the recording sensitivity, the film made of the chalcogenide mentioned above has a composition with a melting point as low as possible, that is, a film composition with a large amount of Te. The fact that To is greater than other additive components means that phase separation is more likely to occur in the repeatability. Therefore, how to fix the excess To added to lower the melting point and make it difficult to move will have a large effect on the cycling characteristics, ONR, and fluctuations over time in the erasure rate.

Recording members containing oxides also have drawbacks as described below. That is, the erasure rate decreases due to repeated recording and re-erasing.

In a rewritable optical disc, recording is normally performed with the initial state being a crystalline state and the recording state being an amorphous state. The erasure is made crystalline like the initial state.

This crystalline-amorphous phase transition of the recording member is achieved by changing the conditions of slow cooling and rapid cooling using a laser.

That is, after heating with laser light, it becomes crystalline by slow cooling, and becomes amorphous by rapid cooling. Therefore, by repeating recording and erasing L7, the film passes through the crystalline and amorphous states many times. In this case, if an oxide is present in the film, the viscosity of the film is high, so the migration of chalcogenide is reduced, and segregation of the film composition is likely to occur. Furthermore, the presence of oxides impairs the thermal conductivity of the film itself, resulting in a difference in temperature distribution between the film thickness on the laser beam incident side and the opposite side, resulting in segregation of film composition. For these reasons, films containing oxides have the disadvantage that their characteristics gradually change due to repeated recording and erasing.

The present invention aims to improve the repeatability of the film containing the above-mentioned oxide, and furthermore, the disadvantages of the conventional composition made of chalcogenide (low C/N, insufficient erasing rate, 1. moisture resistance, This overcomes the problems of poor heat resistance and insufficient repeatability.

Means for Solving the Problems The recording layer in the present invention is composed of a Te-Go-8θ-sb system, and the atomic ratio of Te, Ge, and Se is as shown in FIG. It is located within the region connecting the points 'DI' El and is made of a material having an Sb concentration of 15 to 40 at%.

Function The present invention is characterized by a high crystallization transition temperature, Te-Ge-
The purpose is to fix excess Te by adding 5b-q to the 8e system. Sb forms a compound (Sb 2 Te 3) with Te, and in a 5b-Te system with a Te concentration of 60% or more, the highest melting point is 622°C even in (Sb 2 Te). This temperature is nearly 150°C lower than other To-Ge, Te-3n, etc. Therefore, the addition of sb makes it possible to fix excess Te without increasing the melting point of the film used as the base material.

Example The present invention is composed of Te-Go-3e-3b.

In the present invention, To is combined with sb or Go, and oSe, which is a base material that exhibits optical density changes before and after recording, can easily be used alone or in a compound state with Te to form an amorphous film. Although it has certain characteristics, it has drawbacks such as slow crystallization rate and low crystal transition temperature (=100'C). To-36
By adding KG6f, the crystal transition temperature increases, but the crystallization rate is not improved, and the crystallization rate (several hundred ns) required for practical use of the original disk cannot be obtained. While taking advantage of the above-mentioned features of the 5s system, namely its high crystal transition temperature, the addition of sb2 significantly improves the drawback of this system's slow crystallization rate, making it possible to rewrite for practical use. The aim is to provide a complete range of recording films.

In the present invention, Te, Go, Se, and sb are in a crystalline state, and GeTe, Gage2. It is thought that it takes a crystalline state such as Sb 2To. Among these, Ga5
52 is stable in the amorphous state, and the crystallization temperature is 470℃
Moreover, the crystallization rate is slow. Therefore, in the film, it seems to play a role mainly in increasing the crystallization transition temperature and facilitating amorphization. Ge-T.

Depending on the ratio of Go and TeO, there are regions where crystallization is easy, and
Separate into difficult areas. In other words, the region where the amorphous state is most stable in the Ge-Te system is ee' where the Ta concentration is about 70%.
This is the area where re2 is generated. As Ge increases beyond this point (as Go Ta concentration, which is close to stoichiometry, increases)
, the crystallization rate becomes faster. In the present invention, Ge is Gag
In addition to e, , GaTe f is formed, and Te
In the -Ge-3a system, GeTa seems to contribute to improving the crystallization rate. However, in a system composed of Te-Go-8s, a composition with a practically high crystallization rate has a small amount of So (in a region close to the stoichiometry of GeTe).

The feature of this region is that although the crystallization rate is fast, GeTl!
Since the melting point of y is as high as 725°C, it is difficult to make it amorphous. Therefore, it is the region where the Ge concentration is low and the SO concentration is high that allows crystallization and amorphization in a practical region.

This region is characterized by a high crystallization temperature but a slow crystallization rate. The addition of sb causes excess To and 31 in the film.
) The element that promotes crystallization in a compound with oTθ that forms 2T63 and promotes crystallization is the above-mentioned s.
Not limited to b, but also Sn, Pb, Pa.

There are various materials such as Ni, Go, and Cr. These materials certainly have the characteristic of high crystallization speed, and by limiting the amount added, write-once materials (W10 materials) can be created.
However, it is not suitable as a rewritable source disc material. The reason for this is that the alloy composed of the above-mentioned elements and Te has a high melting point.

However, even such materials can be used as erasable disks if the laser power is strong and the film can be sufficiently melted.

Currently, the semiconductor lasers that we can practically obtain have a wavelength of 830 nm and a power of about 30 mW.
It is difficult to melt a composition (TeGe, GaSe□) close to the stoichiometry of Se. (Melting point is around 800℃)
The area that can be recorded and erased with To-Go-8e is in an area where To is extremely high (more than goat%), but the composition of this area has a low transition temperature and is thermally unstable.
Due to the excessive amount of ions, the film tends to undergo phase separation between Te and TeGe or Gem52 due to repeated use.

The sb of the present invention converts this excess To into Sb 2T e 3
It has a stabilizing function. When sb is alloyed with To, the melting point is 622°C when To is 50&t% or more.
In the following, even if sb is added, since the melting point of To is 451°C, the melting point will not be increased that much. Therefore, S
A film doped with b can be sufficiently melted even with current semiconductor laser power. Moreover, because the thermally unstable excess To is combined as Sb 2Te 3,
The film is thermally stable, does not undergo phase separation even after repeated recording and erasing, and remains stable for a long period of time.

The amount of sb added is determined by the remaining excess To combined with Ge and Se.
Since f is fixed, the required St) concentration is To/(Ga
+Se).

That is, the amount of 5b(7) added varies depending on the composition ratio of the Go-To-3e system. For example, in a region where the Se content is relatively large (Se > 2 ts at %), the amount of Sb added to promote crystallization increases because it is stable as an amorphous state. (25 to 402Lt%) Conversely, in a region with a small amount of Se acid component (Se≦1sat%), the crystallization rate is relatively fast, so a small amount of Sb (15 to 3oILt%) is sufficient. Similarly, areas with high Go concentration (Ge≧251Lt%)
The crystallization rate is fast, so the Sb concentration is low (16-30
at%) Area with low Ge component (GOku1o&t%)
Since crystallization is difficult, a relatively large amount of sb is required.

FIG. 1 shows the appropriate range of the recording member made of T e -G e -3n-8b of the present invention. The figure is Te-
Although it is composed of Ge-8e, the Sb concentration is 15 to 40at compared to the Te-Ge-3e composition shown in FIG.
%.

(The Sb concentration is (TexGeySnz),...-!11S
Corresponds to m when expressed as bm, however, x + y + z
=10o) In FIG. 1, each point has the following composition.

4 points: Te,. Go5Se5 84 points: Te6oGe5Se.

C4 point: Te6oGe5Se, 5 D4 points: Te4oGe4oSe2゜ B1 point” “55” 40S’5 The present invention is directed to the above-mentioned Te-Ge-3e ternary system.

B, , C, , D, , within the range surrounded by points,
And the Sb concentration is expressed as (ToxGeySez). . -m
When expressed in Sbm, the value of m is 16 to 40&
It is within the range of t%. When the Ge content is less than the line B, To-3e is excessive in the film, and the crystallization transition temperature is low (<120'C), making it difficult to obtain a practically stable recording film.Line B, Tea if there is more SO than C1
The amount of Gene 2 formed increases, resulting in a stable amorphous film, making crystallization difficult. Lines C, D, Te
When the amount of 5b2T03 is small, the amount of 5b2T03 required for crystallization is also small, so the contrast ratio between the signals of the recorded area and the unrecorded area is low, and sufficient recording characteristics cannot be obtained.

When there is more GO than linear, IC, and IC, this region is the region where stoichiometric GeTe is produced, and the crystallization rate increases, but
Since a large amount of Go To having a high melting point exists, it is difficult to make it amorphous. When the amount of Se is smaller than the amount of line laminate IC1, the amount of Gene2 will be smaller, making it difficult to amorphize. However, if there is less Ge on the same 1” i-line, Ge
Since the amount of Te is small, it is relatively easy to become amorphous, but the crystallization transition temperature becomes low.

The above-mentioned tendency naturally varies depending on the amount of sb added. Totally limited composition consisting of Te-Ge-8e sb
When the amount is changed, when the amount of Sb is small, it becomes easy to become amorphous, and as the amount of Sb increases, crystallization becomes easier. This appropriate amount of sb is Te, Ge.

Although it varies depending on the characteristics of the film composed of SO, within the scope of the present invention, a practical rewritable recording film can be obtained at 16 to 40&t%.

For the reasons stated above, the present invention is limited to the range surrounded by the point Mj ``l-C1-''j ''1 in FIG. 1. That is, the Te-Go-
When 15 to 40 at% of Sb f is added to 8e, information can be recorded and erased by fully utilizing the reversibility of crystalline and amorphous states.

Next, we will discuss the area surrounded by M2"2-C2-B2-B2 or M5-B, -C5-D3-x5 in FIG. 1. This area is defined by M1-B+ in FIG.
The ranges surrounded by -〇, -D, and -IC indicate more practical composition ranges.

In Figure 1, A 2-B 2-C, -D 2-E
2 The composition of each point is shown below.

Mu2: To83Ge7Se1゜ B2: Te63Ge7Se3゜ C2: Te45Ge3oSe25 D2: Te45Go, 5Se2゜ IC2: Te55Go,,,Se,.

The Sb concentration in the area surrounded by each point is 16 to 30
It is 1Lt%. (However, (Te6Ge5Se2),
. . -1nSbm with no value, X+7+Z=
Set it to 100. ) The transition temperature from amorphous to crystalline in this region is 150-2
The 0 transition temperature, which is within 20°C, is the lowest for Mu2, and the line C
As the so and Ge concentration increases in the 2D2 direction, the temperature increases. The i concentration necessary to promote crystallization is mu2
0, that is, it is less in the area near the point and more in the area near the line C2D2.

In the region close to C2D2, there is a large amount of excess Te and the crystallization rate is fast, so a large amount of sb is not required. In the region close to C2D2, crystallization is difficult, so a large amount of Bi is required.

As a result, at point 1, the amounts of GaTa and G55a2 are small and excess Tθ remains, so a stable amorphous state is not formed and the crystal transition temperature becomes low. When the amount of So increases from the point 2 (82 points), the transition temperature increases, but the crystallization rate slows down. When the amount of GO increases from point M2 to point M2, the transition temperature increases and the crystallization temperature also increases, but it becomes difficult to make it amorphous.
As for the point surrounded by Even within the area surrounded by the two points 2-B2-C2-D2-, the current commercially available semiconductor laser output (25
mW), recording and playback may not be possible at all points.

The region surrounded by point 5 B 5-03-D 5 ICs can be recorded and played within the current semiconductor laser power range, has a fast crystallization rate, and has a crystallization transition temperature that indicates thermal stability. The temperature is high (160-216°C) and is in a more practical range. The required amount of sb in this area is 25-3
5&t%. The addition of Sb lowers the crystal transition temperature by 10 to 30'C compared to a system consisting only of Te-Ga-8θ.
It has the function of enhancing. Furthermore, the addition of sb lowers the melting point of the film, which is advantageous for making it amorphous. The reason for this is that when Sb is 40% or less of the Te concentration, the melting point is at most 622°C or less. On the other hand, in the case of Go, Sn, etc., with respect to the Te concentration,
If it is less than s o at%, each maximum 725°C2
It becomes 79o0. Therefore, the addition of sb has the effect of increasing the transition temperature indicating thermal stability and lowering the melting point of the film, and for the reasons stated above, the Te-Go-8e-sb of the present invention
The optimal composition of is limited.

Next, a method for manufacturing an optical information recording member according to the present invention will be described.

FIG. 2 is a schematic cross-sectional view of an original disk constructed using the recording layer of the present invention. In the figure, 1°6 represents the substrate, and the material can be a transparent base material such as polycarbonate, acrylic resin, glass, polyester, etc. 02 and 4 are protective layers, which can be made of various oxides, Sulfides and carbides can be used. This protective layer 2.4 prevents thermal deterioration of the base material due to repeated recording and erasing of the recording film 3, and further protects the recording film 3 from humidity. Therefore, the material and thickness of the protective layer are determined from the above-mentioned viewpoints. The recording film 3 is formed by vapor deposition, sputtering, or the like. In the case of vapor deposition, it is preferable to use a four-source vapor deposition machine capable of individually vapor depositing each composition, since a uniform film can be formed.

The film thickness of the recording film 3 of the present invention is set to a value that matches the optical properties of the protective layers 2 and 4, that is, a value that allows a large difference in reflectance between recorded and unrecorded areas.

Hereinafter, the present invention will be explained in detail using a specific example.

Example 1 Using an electron beam evaporator capable of four-source evaporation, Te, G6
,8+5. Sb'iz was simultaneously deposited onto the substrate from each source. The base material used was glass with a diameter of 81 rml.
For vapor deposition, the degree of vacuum was 1×10 Torr, the rotation speed of the substrate was
It was conducted at 150 rpm and the film thickness was 1000. The deposition rate from each source is the Te in the recording film.

The ratio of the number of atoms of Ge, Se, and Sb was changed to adjust the ratio. The composition ratios in Table 1 are values converted from the rate of vapor deposition, but when carried out using a typical composition 6 X-ray microanalyzer (XM Jin), quantitative results almost the same as the starting values were obtained. . Therefore, it seems that the feed composition in the table is the same in the film.

The evaluation method of the test piece produced by the above manufacturing method is described below.

[Transition temperature]

The term "transition temperature" refers to the starting temperature at which a film in an amorphous state immediately after vapor deposition changes to a crystalline state due to heat. The measurement was carried out using a device capable of measuring the transmittance of the membrane, and the temperature at which the transmittance started to decrease when the temperature of the test piece was raised by a heater at a heating rate of 1° C./sea was set.

A high transition temperature means that the film is thermally stable. [Blackening, whitening properties] Blackening properties indicate the rate of transformation from amorphous to crystalline. The whitening property indicates the transition speed from crystalline to amorphous.

The measurement was carried out using a device that focused a laser th on a recording film on a glass piece of φ8ff using a lens, and was able to move the sample piece vertically and horizontally.

The laser beam spot is 45X0.4μIII, H/
L/S width 200n! I, power density 10.8mW/
The pd wavelength was 900n11. The blackening characteristics are determined by observing the speed of transformation (from amorphous to crystalline) when the specimen is moved relatively slowly. Those that are sufficiently large are marked as ◎. × indicates that the image does not turn black even when moved slowly, or that the contrast ratio is small. ○、△ is ◎
It is located between and ×. In this qualitative expression, the practical blackening characteristic is 0 or more.

Next, we will discuss the whitening properties. If you want to see all the whitening characteristics,
First, once it becomes black, the test piece is quickly moved over it to create a quenched state, causing it to turn white (from crystalline to amorphous). A whitening state ◎ indicates that whitening occurs even if the moving speed is relatively slow, and the contrast ratio between the amorphous portion and the crystalline portion is large, and × indicates that there is no whitening at all. O and △ are located between ◎ and ×.

According to the above expression, if both blackening and whitening properties are very good, it will be ◎ or ◎, but in reality, it is possible for both to be ◎ at the same moving speed, so it is a desirable material. The blackening properties are ◎, ◎, ◎, ∆, and the blackening properties are somewhat excellent.

Table 1 shows the results of the transition temperature, blackening, and whitening characteristics of a film prepared within the scope of the present invention with an sb concentration of 30 at%. As such, the Ta-Ga-3s-3b recording thin film within the scope of the present invention can be blackened and whitened. A recording member within the range of i() can be in either an amorphous state or a crystalline state by appropriately selecting the heating conditions, such as the irradiation intensity and irradiation time of the laser beam. , it is possible to optically record and erase the amounts.

In this example, the concentration of sb was 30 at%,
The above-mentioned blackening and whitening characteristics strongly depend on the concentration of Sb. On the other hand, the transition temperature also depends, although not so strongly, on the Sb concentration.

Example 2 Te-Ge-
Table 2 shows the results of investigating the concentration dependence when sbl was added to the 8e system. - For example Te 6oGθ20
The Sθ2o composition is selected and the Sb concentration i is varied within the range of 10 to 45&t%.

As is clear from the results in Table 2, Te6oGe2o
When Sb f is added to Sθ2°, the Sb concentration is 16 to 4
Qat%, by laser beam, crystallization,
Any of these can be made amorphous and is effective as an optical recording member.

When crystal-amorphous phase transformation is used as the recording principle, the recording (amorphization) speed is determined by the time it takes for the irradiated area to melt,
The erasure (crystallization) rate depends on the time it takes for the order of the atomic arrangement to be restored, and the former is generally much faster than the latter. Therefore, when the composition region of the present invention is applied to, for example, an original disk, the erase speed mainly determines the specifications of the device.

That is, the composition may be selected depending on the conditions of use as a device, for example, in the case of an original disk, its rotational speed recording radius (linear velocity). That is, in the case of a composition with a low Sb concentration, the recording sensitivity (whitening sensitivity) is high, but the erasing sensitivity (blackening speed) is high.
is low, so it is effective when the rotation speed is relatively slow. On the other hand, in the case of a composition with a high Sb concentration, the erasing sensitivity (blacking speed) is sufficient, so that it can be applied to high-speed rotation. However, in this case, a slightly higher recording power is required.

The effect of adding sb differs slightly depending on the composition ratio of the Ge-Te-3s system. For example, a region with a relatively large amount of Se (
Se〉25 at%), the region with relatively high Sb concentration (26 to 40 at%) shows good characteristics;
In a region with a small e component (Se less than 1 sat%), a region with a relatively low Sb concentration of 15 to 30 at% showed good characteristics. Similarly, a region with a relatively large amount of Go acid components (Ge
, 2252Lt%), the region with relatively low Sb concentration is 16 to 30at%, and the region with low Cte component (Ga
/1oat%), region 2 with relatively high Sb concentration
5 to 40 at% showed good properties.Example 3 1, 2t×φ with a track for light guide as a base material
A prototype original disk was produced using a 200H polycarbonate resin base material, a recording film, and a (Te GeSe ) Sb (7) conductive film.

First, a ZnSnS thin film of 19 times the thickness was deposited as a heat-resistant layer on the base material, and a ZnS thin film of 1,800 times the same as the heat-resistant layer was further deposited thereon.

A laser beam focused using an optical system was irradiated from the substrate side of the original disk to record a signal, and the signal was immediately erased. Prior to recording, the spot shape was 1 meter x 1 meter.
1oIl! The recording film in the track was irradiated along the track with an elongated laser beam i having an intensity of 14 mW, and the recording film in the track was crystallized, and then a laser beam i narrowed to 0.9 μmφ was irradiated with an intensity of 8 mW. The recording frequency was 2MH2, and the rotational speed of the disk was ts m/s. At this time, the irradiated area was made amorphous and a signal was recorded along the track. When c/Nw was measured with a spectrum analyzer, a value of 55 dB was obtained.When the above-mentioned long elliptical spot was irradiated onto this track, the signal disappeared completely.

Example 4 Using the original disk in Example 3, a life test was conducted for 80
The test was carried out under the conditions of °C and 60% RH.

The test method was to record information in advance and observe the deterioration of C/N after holding under the above conditions. The decrease in C/H after one month was -0.5 dB, which was negligible.

Example 6 The recording and erasing repetition characteristics of the original disk in Example 3 were evaluated.

After repeating recording and erasing 100,000 times, the decrease in c7N- was about 1 dB.

Effects of the Invention The Ta-Go-8s-3b recording thin film of the present invention is as follows:
It has excellent heat resistance and moisture resistance, and the film will not be destroyed even after repeated recording and erasing. That is, the present invention provides an optical information recording member that is excellent in practical terms.

[Brief explanation of drawings]

FIG. 1 is a composition diagram showing the composition range of an optical information recording member according to the present invention, and FIG. 2 is an example of the present invention. Name of agent: Patent attorney Toshi Nakao

Claims (4)

[Claims] (1) The main components are Te, Ge, Se, and Sb, and Te, G
The atomic ratio of e and S is A_1(Te_9
_0, Ge_5, Se_5), B_1(Te_6_0,
Ge_5, Se_3_5), C_1(Te_4_0, G
e_2_5, Se_3_5), D_1(Te_4_0,
Ge_4_0, Se_2_0), E_1(Te_5_5
, Ge_4_0, Se_5), the concentration of Sb (at%) changes the overall composition to (Te_
x, Ge_y, Se_z)_1_0_0_-_mSb_
An optical information recording member comprising a thin film in which, when expressed as m, 15≦m≦40 at%. (2) The atomic ratio of Te, Ge, and Se is A_2 (Te_8_3, Ge_7, Se_1_0),
B_2 (Te_6_3, Ge_7, Se_3_0), C
_2 (Te_4_5, Ge_3_0, Se_2_5),
D_2 (Te_4_5, Ge_3_5, Se_2_0)
E_2 (Te_5_5, Ge_3_5, Se_1_0)
The concentration of Sb (at%
) is 20≦m≦35 at%, the optical information recording member according to claim 1. (3) The atomic ratio of Te, Ge, and Se is A_3(Te_7_5, Ge_1_0, Se_1_5 in Fig. 1).
), B_3(Te_6_5, Ge_1_0, Se_2_
5), C_3(Te_5_0, Ge_2_5, Se_2
_5), D_5(Te_5_0, Ge_3_0, Se_
2_0), E_3(Te_5_5, Ge_3_0, Se
_1_5) The optical information recording member according to claim 1, wherein the concentration (at%) of Sb is 25≦m≦35at% in the area surrounded by each point. (4) The composition is (Te_1_0_0_-_p, Ge_p,
The optical information recording member according to claim 1, wherein when expressed as Se_2_0)_1_0_0_-_mSb_m, 10≦p≦25 and 25≦m≦35at%.