JPH023114A - Thin film for recording information - Google Patents

Abstract

PURPOSE:To obtain a recording material which can be manufactured easily and has good reproductivity and long-life stability by selecting the average composition in the direction of film thickness to satisfy a specific formula. CONSTITUTION:The film for recording informations is formed directly on a substrate or through a protective layer consisting of at least one of organic or inorganic compound. The recording film shows no change in its appearance when irradiated with a beam for recording, while the atomic arrangement in the film changes. The recording film has the average composition in the thickness direction as discribed in general formula I. Thereby, the recording film can be manufactured easily and is stable for a long period with good reproductivity and recording/(erasing)reproducing characteristics.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a recording method using a recording beam such as a laser beam or an electron beam.
For example, it relates to an information recording thin film that can record in real time FM modulated analog signals such as video and audio, computer data, facsimile signals, digital audio signals, and other digital information. be.

[Conventional technology]

There are various recording principles for recording on thin films using laser light, but recording based on changes in atomic arrangement such as phase transition (also called phase change) of the film material and photodarkening involves almost no deformation of the film, so two sheets are used. It has the advantage of being able to create double-sided discs by directly bonding two discs together. Furthermore, if the composition is appropriately selected, it is also possible to rewrite records. Many inventions related to this type of recording have been filed, and one example is disclosed in Japanese Patent Publication No. 47-26897, for example.

Furthermore, a thin film containing Ge, Te, and sb as main components is disclosed in Japanese Unexamined Patent Publication No. 61-258787, and its recording film composition is ((S b xT ez-x)yG e x- y)i
-zMz (or 0.2 to 0.7, y is 0.4
~0.8.2 is a number in the range of 0.01 to 0.5;
M is AQ, Si.

It is an element selected from a group of 37 metal elements such as Ti).

[Problem to be solved by the invention]

When the thin films shown in the above-mentioned prior art are used as one-time writable or rewritable phase change recording films, the activation energy for crystallization of amorphous recording points is small, so crystallization occurs during energy beam irradiation. The speed is small,
It has the disadvantage that the stability of the amorphous state at room temperature is poor, and the reproduced signal intensity is not sufficiently large. This method has drawbacks such as an insufficient number of rewriting repetitions and a large amount of residual signal remaining when overwriting with a single beam, making it difficult to put it into practical use.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to provide a thin film for information recording that has good recording/reproducing characteristics, high sensitivity, and good stability.

[Means to solve the problem]

In order to achieve the above object, in the information recording member of the present invention, the average composition in the film thickness direction of the information recording thin film is expressed by the general formula %, where X Hyg Z Hα and β are each 8
0, 1 < z < 10, 0 < a < 20
, O<β20.1<α+β20, and A is at least one element among Tl, a halogen element, and an alkali metal element. These elements are Te
It has the effect of cutting the chain-like atomic arrangement of Te in materials containing Te and increasing the crystallization rate. However, since it is accompanied by a decrease in the crystallization temperature, it will become amorphous if it is not added to a material with a high crystallization temperature. This will impair the stability of

B is Co, Fe, Ni, Sc, Ti, V.

Cr, Mn, Cu, Zn, Y, Zr, Nb, MowRu
, Rh, Pd, Ag, Cd, Hf, Ta, W.

At least one element selected from Re, ○s, Ir, Pt, and A +i.

The recording thin film of the present invention may have a composition change in the thickness direction as long as the average composition in the film thickness direction is within the above range, but it is more preferable that the composition change is not discontinuous.B It is an element represented by

Transition metal elements such as Co easily absorb long-wavelength light such as semiconductor laser light, increasing recording sensitivity, and also have the effect of raising the crystallization temperature, that is, increasing the stability of the amorphous state. Moreover, it itself has a high melting point of 600° C. or higher, or forms a compound with a high melting point, and when crystallized by laser light, it does not melt even at high temperatures, so high-speed crystallization is possible.

The information recording thin film of the present invention having the above composition range has excellent recording and reproducing properties, and requires low power of laser light used for recording and erasing. It also has excellent stability.

A more preferable range of Xr y+Z+ α and β is 20
< x < 45, 55 < V < 70, 1
−<z<10.

0 α<20. O<β<20.1<α+β20. Particularly preferable ranges of −Xry+Z+ α and β are: 20 < x < 40, 60 < y < 70,
1 < Z < 10.

0 α<15. O<β<15.1<α+β<20.

In a recording film whose component elements are only Ge, Te, and sb, the activation energy for crystallization of an amorphous recording point is small, the shortest irradiation time (erasing time) required for erasing is long, and the amorphous recording point The stability is also poor. By adding the element represented by 8, the erasing time is shortened, and by adding the element represented by B, the stability of the amorphous recording point is improved.

Among the elements represented by A, particularly preferred are Tl, followed by I and Na. Further, among the elements represented by A, Co is particularly preferred, Ti is the next most preferred, V is the next most preferred Ni, V is the next most preferred, and Pd, Zr, Nb and Mn are the most preferred.

It is preferable that at least one surface of the recording film of the present invention is closely protected by another substance. It is even better if both sides are protected. These protective layers may be formed of an acrylic resin board, a polycarbonate board, an epoxy resin board, etc. which is also a substrate, or an organic material such as acrylic resin, epoxy resin, polyimide, polyamide, polystyrene, polyethylene, etc. thing.

Fluoride, nitride, sulfide, carbide, boride, boron,
It may be formed from an inorganic material whose main component is carbon or metal. Also, these composite materials may be used.
At least one of the protective layers adjacent to the recording film is preferably inorganic.

Substrates based on glass, quartz, sapphire, iron, or aluminum can also serve as one inorganic protective layer. Among organic substances and inorganic substances, those in close contact with inorganic substances are preferable in terms of heat resistance. However, increasing the thickness of the inorganic layer (except for the substrate) may cause cracks to occur, decrease in transmittance,
Because it is likely to cause at least one of the following:
It is preferable that a thick organic layer be closely attached to the side of the inorganic layer opposite to the recording film in order to increase mechanical strength.

This organic layer may be a substrate. This also makes deformation less likely to occur. As the organic material, for example, polystyrene, acrylic resin, polycarbonate, epoxy resin, polyimide, polyamide, ethylene-vinyl acetate copolymer known as a hot melt adhesive, adhesive, etc. are used. In the case of a protective layer made of an inorganic material, which may be an ultraviolet curable resin, it may be formed as it is by electron beam evaporation, sputtering, etc., but it may be formed by reactive sputtering or a protective layer made of at least one element of a metal, semimetal, or semiconductor. After forming the membrane.

Production is facilitated by reacting with at least one of oxygen, sulfur, and nitrogen. Examples of inorganic protective layers include Ca, La, Si, and In.

AQ, Ge, Pb, Sn, Bi, Te, Ta.

An oxide of at least one element selected from the group consisting of Sc, Y, Ti, Zr, V, Nb, Cr, and W, Cd,
Zn, Ga, In, Sb+Ge.

Sulfides of at least one element selected from the group consisting of Sn and Pd, or selenides, fluorides such as Mg + Ce + Ca, nitrides such as Si, fi, Q, Ta, and B, borides such as Ti , carbides such as boron, boron,
It consists of carbon, for example, the main component is CeOz
, LazOa+Sin, 5iOz.

I n 20a, A Q zos, G e○, G
eOz, PbO.

Sn○, SnO2, Biz○a, T e Ox, W
OzrWOs, T axos, S czoa, Yy, O
s, T i 0xtZrC)z, CdS, ZnS, Cd
Se, Zn5e.

I nzsg, I nxs 8s, S biss, S
bzs e3+G azss+ G azs all
, M g Fil Ce Fz.

Ce F3. Ca Fz, GeS, Ge S e, Ge
Sez+SnS, 5nSe, PbS, Pb5e, Biz
Ses.

BizSz, TaN, S 1sN5 AQN, Si.

It has a composition close to one of Ti Bi B4C, B, and C.

Among these nitrides, TaN is preferred because its surface reflectance is not very high and the film is stable and strong.

Preferably, the composition is close to Si3H4 or Al2N. Preferred oxides are YxOs and 5cxos.

Ce0z, Ti0z, Zr()z, InzOg, AQz
○δ.

The composition is close to 5nOx or 5iOz.

Amorphous materials containing Si or C hydrogen are also preferred. When recording by phase transition, it is preferable to crystallize the entire surface of the recording film in advance, but if the substrate is made of an organic substance, it is not possible to heat the substrate to a high temperature, so crystallization can be performed using other methods. It is necessary to do so. In that case, it is preferable to perform ultraviolet irradiation and heating, light irradiation from a flash lamp, light irradiation from a high-power gas laser, or a combination of heating and laser light irradiation. In the case of light irradiation from a gas laser, the light spot diameter (half width) is set to 5μ.
Efficiency is good if the length is between m and 5 m.

Crystallization may occur only on recording tracks, and the space between tracks may remain amorphous. Of course, it is also possible to record on an amorphous recording thin film by crystallization.

Generally, when a thin film is irradiated with light, the reflected light is a superposition of the reflected light from the surface of the thin film and the reflected light from the back surface of the thin film, causing interference. When reading signals based on changes in reflectance, by providing a light reflecting (absorbing) layer close to the recording film, the interference effect can be increased and the readout signal can be increased. In order to further enhance the interference effect, it is preferable to provide an intermediate layer between the recording film and the reflective (absorbing) layer.

The intermediate layer also has the effect of preventing mutual diffusion between the recording film and the reflective layer during recording and rewriting. The intermediate layer is preferably made of a material that does not absorb much of the light used for reading. The thickness of the intermediate layer is 3 nm or more and 400 nm or less, and the reflectance of the recording member near the wavelength of the reading light in the recording state or erasing state. It is preferable to set the film thickness to a value close to the minimum value. The reflective layer may be formed either between the recording film and the substrate or on the opposite side. A particularly preferable thickness range of the intermediate layer is from 5 nm to 150 nm. It is preferable to form a protective layer made of the above-mentioned inorganic material also on the side of the reflective layer opposite to the intermediate layer.

In addition, recording light and erasing light are provided on the light incident side of the recording layer.

Preferably, an antireflection layer is formed that reduces the reflectance of at least one of the readout lights. The antireflection layer may also serve as a protective layer for the recording film, or a protective layer may be formed between the antireflection layer and the recording film. It is preferable that the coefficient of thermal expansion changes sequentially in the order of anti-reflection layer - substrate, adhesive or gas, and even when one of the protective layer and anti-reflection layer is not formed or each consists of two or more layers, the coefficient of thermal expansion changes sequentially. It is preferable that the values change sequentially.

The recording film of the present invention can be produced by co-deposition, co-sputtering, etc. using oxides, fluorides, etc., which can be used as a protective film.
It may also be in the form of being dispersed in nitrides, organic substances, etc. By doing so, it may be possible to adjust the light absorption coefficient and increase the reproduction signal intensity. The mixing ratio is oxygen and fluorine.

The proportion of nitrogen and carbon in the entire film is preferably 40% or less. By forming such a composite film, the speed of crystallization generally decreases and the sensitivity decreases. However, forming a composite film with an organic material improves sensitivity.

The preferred range of film thickness for each portion is as follows.

For recording film multilayer film: 60 nm or more and 350 nm or less, 80 nm
A range of from nm to 200 nm is particularly preferable in terms of reproduction signal strength and recording sensitivity.

In the case of a two or more layer structure with a reflective layer, 15 nm or more and 1100 nm or less Inorganic protective layer 5 nm or more and 200 nm or less However, when protecting with the inorganic substrate itself, 0.1 to 20 mm Organic protective film: 10 nm or more and 10 mm or less Intermediate layer: 3 nm 400 nm or more Light reflective layer: 5.
The method for forming each layer with a thickness of 300 nm or more is vacuum evaporation, gas evaporation, sputtering, ion beam sputtering, ion beam evaporation, or ion blating.

Any one of electron beam evaporation, injection molding, casting, spin coating, plasma polymerization, etc. is selected as appropriate.

The recording film of the present invention does not necessarily need to utilize a change between an amorphous state and a collapsed state for recording, but it is sufficient to cause a change in optical properties by some kind of atomic arrangement change.

The recording member of the present invention can be used not only in the form of a disk but also in other forms such as a tape or a card.

[Effect]

The information recording thin film of the present invention has a high crystallization speed, high stability in the amorphous state, high absorption of semiconductor laser light, high reproduction signal intensity, and good oxidation resistance. Therefore, the recording/erasing characteristics are good, the sensitivity is high, and the stability of the recording state is good.

[Example 1] The present invention will be explained in detail below using Examples.

A replica of a tracking groove that also serves as a protective layer is formed on the surface of a disk-shaped chemically strengthened glass plate with a diameter of 131 mm and a thickness of 1.2 m using ultraviolet curing resin. , the track address, sector address, etc. are inserted in the form of uneven pits in the mountainous part between the grooves (this part is called the header part).
First, a 5isN layer with a thickness of about 1100 nm, which is an anti-reflection layer and a protective layer, is formed on the substrate 14 by magnetron sputtering.
A layer was formed. Next, this substrate was placed in a vacuum evaporation apparatus having an internal structure as shown in FIG. Four evaporation sources 1, 2, 3.4 are arranged in the vapor deposition apparatus. Three of these are resistive heated deposition boats and one of these is an electron beam evaporation source. These boats and the electron beam evaporation source are located below the portion where information is to be recorded on the substrate 14 and aligned with the central axis 5 of substrate rotation.
It is located approximately on the circumference of a circle whose center is the same as that of .

Two deposition boats were charged with G e -Te compounds, Sb, and Tl, respectively, and an electron beam evaporation source was charged with CO. Masks 6.7 and 8.9 with fan-shaped slits and shutters 10.11 are provided between each boat and the board, respectively.
, 12.13 are arranged.

While the substrate 14 was being rotated at 12 rpm, a current was applied to each boat, and an electron beam was applied to evaporate the deposition raw material.

The amount of evaporation from each evaporation source is measured by the crystal oscillator type film thickness monitor 15.
．． 16, 17, and 18, and the current was controlled so that the evaporation rate was constant.

As shown in FIG. 1, a 5isNa layer 20 on a substrate 19
A recording film 21 having a composition of GezsTaezSbsT Q a is deposited thereon to a thickness of about 1100 nm.
Since the Na layer has a higher refractive index than the substrate, it also serves as an anti-reflection layer for semiconductor laser light by making the film thickness appropriate. This film thickness is noted below.@When the recording film is in a non-collapsible state or a state with poor crystallinity, the reflectance is almost minimal near the wavelength of the laser beam used for reading. The film thickness is such that Subsequently, the protective layer 22 having a composition close to 5 is Na was made to have a thickness of about 1100 nm by magnetron sputtering again. Similarly, S i ! is placed on another similar substrate 19'. Protective layer 20' with a composition close to 1N4, GezgTeeaSb4T
A recording film 21' having a composition of Q s and a protective film M22' having a composition close to 51 g Na were deposited. An ultraviolet curable resin protective layer 23 and 23' is applied to a thickness of about 50 μm on each of the vapor deposited films of the two substrates 19 and 19' thus obtained.
After forming, both are coated with ultraviolet curing resin layers 23 and 23'.
A disk was produced by laminating the disks with the sides inward using the active material adhesive layer 24.

After heating the disk prepared as above at 150°C for about 1 hour, the disk was rotated and moved in the radial direction to increase the numerical aperture ratio (Nu+aerial Apertu) from both sides.
The recording film 21 is irradiated with argon ion laser light (wavelength 488 nm) focused by a lens with re) of 0.05.
．． 21' was sufficiently crystallized.

Recording was done as follows. 1200r disc
pm, the light from the semiconductor laser (wavelength 820 nm) is kept at a level that does not allow recording, and the light is focused by a lens in the recording head and irradiated through the substrate onto one recording film.
By detecting the reflected light, the head was driven so that the center of the light spot was always aligned between the tracking grooves. By doing this, the influence of noise generated from the groove can be avoided. While tracking in this manner, automatic focusing was performed so that the focus was on the recording film, and recording was performed by increasing the laser power according to the information signal or returning it to the original level.

In addition, recordings were made by jumping to other grooves as necessary.

The above recording caused a change in reflectance in the recording film.

In this recording film, a recording light spot with reduced power or a length in the track direction is longer than the recording light spot.
Expansion in the direction of adjacent tracks can also be erased by irradiating laser light of the same magnitude as the recording light spot.

If the distance between the nearest adjacent pits representing addresses is set to 1/2 or more and twice or more the length of the erasing light spot in the track direction, the addresses of trunks and sectors can be read by the erasing light spot as well. The length of the pit representing the address is preferably 172 or more lengths of the erasing light spot in the track direction, and the same applies to other pits provided in a part of the header. Recording/erasing is 3×10
It was possible to repeat it more than δ times. When the 5iaNa layers formed above and below the recording film were omitted, a slight increase in noise occurred after several times of recording and erasing.

Reading was performed as follows. 1200 disks
While rotating at rpm and performing tracking and automatic focusing in the same manner as during recording, the strength of the reflected light was detected using a low-power semiconductor laser beam that was not used for recording or erasing, and information was reproduced.

In this example, a signal output of about 100 mV was obtained.

The recording film of this example has excellent oxidation resistance, and the 5isNi
Even when a sample without a protective film was placed under conditions of 60° C. and 95% relative humidity, almost no oxidation occurred. The recording film of this example had excellent amorphous stability, and the activation energy for crystallization of the amorphous points formed by laser beam irradiation was as large as 2.8 eV.

In the above G e -T e -S b -T O-based recording film, Tl is set to 5 at%, and the sb content (z) is varied while keeping the relative ratio of Ge and Te contents constant. In the case of
) changed as shown in Table 1 below.

Table 1 Table 2 In the above Ga-T e -S b -T It-based recording film, Tl is set at 5 atomic %, and Te content is maintained constant while keeping the relative ratio of Ge and sb contents constant. When the amount (y) was changed, the laser light power required for recording (recording light power), erasing time, and crystallization temperature changed as shown in Table 2.

Furthermore, in the above G e -T e -S b -T Q system recording film, the Tfl content (α) was varied while keeping the relative proportions of Ge, Te, and sb contents constant. In this case, the erasure time and Ea varied as shown in Table 3.

Very similar properties can be obtained by adding Table 3 elements. Among the halogen elements F, CΩ, Br, and I, C is particularly preferred, followed by CQ. Alkali metal element.

Among Li, Na, Rb, and Cs, Na is particularly preferred, followed by K.

In addition, the above G e -T a -S b -Trl
In the system recording film, the relative proportions of Ge, Te and sb are kept constant, and the content of TR (TR content is O
When Co was added (at %) and the Co content (β) was changed, the recording light power and crystallization temperature changed as shown in Table 4.

Here, before forming the upper protective film, the recording film was heated to 60°C.
When left in an atmosphere of 95% relative humidity and 95% relative humidity, deterioration due to oxidation increased when the TΩ content was 15 atomic % or more, and became significant when the TΩ content was 20 atomic % or more.

Here, at least part of the halogen element or alkali metal element is substituted for part or all of Tl. , Te, Sb, and Tu contents by adding CO and keeping the relative proportions of the contents of Co
When the content (β) was changed, the reproduced signal intensity and crystallization temperature changed as shown in Table 5.

Here, the above Ge-Ta-8b-Co system or G
In the e-Te-Sb-T O-G o system.

Part or all of CO may be replaced with Fe or Ni.

S c HT x g V r Cr + M n H
Cu HZ n g Y gZr, Nb, Mo, Ru,
Rh, Pd, Ag.

Cd, Hf, Tar W, Re, Os, I r, pt,
Even if at least one element among Au and Au is added, similar properties can be obtained. Among these, T x r N x + P d is preferable in terms of recording light power;
V and Cr are preferred in terms of reproduction signal strength, Fe and Rh are preferred in terms of erasing time, and Zr is preferred in terms of crystallization temperature.
, Mn are preferable, and from the viewpoint of environmental resistance, Nb, Pt, Au
is preferred.

[Example 2] As shown in Fig. 2, a polycarbonate plate 25 with tracking grooves formed on the surface by injection molding was used as the substrate, and 5iOz was formed by sputtering.
A protective film 26 with a thickness of 200 nm and having a composition close to that of 200 nm was formed.

Next on top of this is Gex5TlBsSbbT Q! 1cO
A recording film 27 having a film thickness of 60 nm was formed with the composition No. 4. Next is the middle one with a thickness of 250 nm and a composition close to SiO2! jI
28 and further a B i7S b+ with a thickness of 80 nm.
A breakdown layer with a composition of 29.5 iOz and a thickness of 1100 with a composition close to
A protective layer 30 of n was formed. Another substrate was prepared in the same manner, and after sputtering polyimide 31 to a thickness of about 0.5 μm on the topmost 5iOz layer 30 of both substrates, a black pigment was applied with the polyimide layer side inside. Both substrates were bonded together using the mixed hot melt adhesive 32 to produce a disk. Polycarbonate board 25.25'
If a polyimide layer is also formed on the surface by sputtering, a more stable disk can be obtained.

The crystallization method, recording method, erasing method, and reading method are almost the same as in the first embodiment.

For the intermediate layer, Ge0z and AQz○δ, which were mentioned in Example 1 as being usable as a protective layer, were used in place of Si○.

Ge0y,, YzOa, S i○, Zr○zt T a
2o! Other inorganic transparent materials such as IIAQN and TaN may be used, or an organic layer may be used. If this intermediate layer has a thickness of 3 to 40 nm, it will prevent mutual diffusion between the recording film and the reflective layer during recording and rewriting, but optically it almost does not exist. Therefore, the change in reflectance due to light interference depending on the wavelength is similar to that in the case of a two-layer structure of a recording film and a reflective layer.

If the reflective layer also undergoes a change in atomic arrangement during recording, the reproduced signal will become a little larger.

When the thickness of the recording film is in the range from 1 Sn to 1100 nm, the reflectance when the recording film is in an amorphous state becomes low due to interference, and a large reproduced signal can be obtained.

The thickness of the reflective layer is preferably in the range of S nm or more and 300 nm or less, more preferably in the range of 40 nm or more and 200 nm or less. By providing a reflective layer, a large reproduced signal can be obtained in a region where the thickness of the recording film is thinner than in the case of a single layer as described above. Good characteristics can be obtained even in a composition range where the absorption coefficient of J is larger than in the case of a single layer.

When the film thicknesses of the recording film and the intermediate layer are changed, the wavelength at which the minimum reflectance of read light occurs due to interference changes. The minimum reflectance required for automatic focusing and tracking is 1.
Since it is 0 to 15%, if the minimum value of reflectance is less than this value, it is necessary to make the minimum value on the longer wavelength side or shorter wavelength side than the wavelength of the readout light. If the minimum value is on the short wavelength side, the thickness of the recording film can be made thinner, and energy loss due to heat transfer can be prevented.6 However, if the minimum value is on the long wavelength side, the film thickness will be thicker. This is preferable in terms of the life of the recording film and the prevention of noise generation during recording and rewriting.

As for the material of the reflective layer, Bi, BizTe8. Te, Sn, Sb.

AQ, Au, Pb, Ni, N
Many semiconductors, semimetals, metals, and mixtures and compounds thereof, such as i-Cr, can be used.

Like the recording film of Example 1, the recording film of this example also has excellent oxidation resistance, and even if there is a pinhole in the protective film, oxidation will not proceed around the pinhole.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to obtain an information recording member that has a simple manufacturing process, good reproducibility, good recording/reproducing characteristics, and is stable for a long period of time. The record can also be rewritten many times.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the internal structure of a vacuum evaporation apparatus used for producing the recording member of the present invention, and FIGS. 2 and 3 are cross-sectional views showing the structure of the recording member in the embodiment of the present invention, respectively. . 1.2.3... Vapor deposition port, 4... Electron beam evaporation source, 6.7, 8.9... Mask with fan-shaped slit. 10.11,12.13...Shutter, 14...Substrate, 15,16,17.18...Crystal resonator type film thickness monitor, 19.19'...Substrate, 20.20'22.
22'...5iaNn layer, 21.21'...recording film, 23.23'...ultraviolet curing resin layer, 24...organic adhesive layer, 25.25'...substrate, 26. 26'2
8.28', 30.30'-8iOz layer, 27°27
'...Recording film, 29.29'...B1-8b film. 31.31'...Polyimide resin layer, 32...Hot 2nd time, g, (5TL

Claims (1)

[Claims] 1. Changes in atomic arrangement without deformation upon irradiation with a recording energy beam formed directly on a substrate or through a protective layer made of at least one of an inorganic substance and an organic substance. In the resulting information recording thin film, the information recording thin film has an average composition in the film thickness direction of the general formula Ge_xT.
e_ySb_zA_αB_β (where x, y, z, α and β are each atomic percent, 20≦x≦60, 40≦y≦80, 1≦z
≦10, 0≦α≦20, 0≦β≦20, 1≦α+β≦2
A is a value in the range of 0, A is at least one element among Tl, a halogen element, and an alkali metal element, and B is Co
, Fe, Ni, Sc, Ti, V, Cr, Mn, Cu, Z
n, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag,
1. A thin film for information recording, characterized in that it is at least one element selected from Cd, Hf, Ta, W, Re, Os, Ir, Pt, and Au. 2. The information recording thin film according to claim 1, wherein the element represented by A is Tl. 3. The information recording thin film according to claim 1, wherein the element represented by B is Co.