JPH02167788A - Information recording medium - Google Patents

Information recording medium

Info

Publication number
JPH02167788A
JPH02167788A JP63322078A JP32207888A JPH02167788A JP H02167788 A JPH02167788 A JP H02167788A JP 63322078 A JP63322078 A JP 63322078A JP 32207888 A JP32207888 A JP 32207888A JP H02167788 A JPH02167788 A JP H02167788A
Authority
JP
Japan
Prior art keywords
recording
recording layer
layer
recording medium
information
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP63322078A
Other languages
Japanese (ja)
Inventor
Tadashi Kobayashi
忠 小林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp filed Critical Toshiba Corp
Priority to JP63322078A priority Critical patent/JPH02167788A/en
Publication of JPH02167788A publication Critical patent/JPH02167788A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24306—Metals or metalloids transition metal elements of groups 3-10
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/2431—Metals or metalloids group 13 elements (B, Al, Ga, In)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24314—Metals or metalloids group 15 elements (e.g. Sb, Bi)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24316—Metals or metalloids group 16 elements (i.e. chalcogenides, Se, Te)

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Thermal Transfer Or Thermal Recording In General (AREA)
  • Optical Record Carriers And Manufacture Thereof (AREA)

Abstract

PURPOSE:To enhance the stability of a recording mark of an amorphous state of a nonequilibrium phase and perform initializing, recording and erasing at a high speed by forming a recording layer of alloy of composition represented by a specific general formula. CONSTITUTION:A protective layer 3, a recording layer 2, a protective layer 4 and a protective layer 5 are sequentially formed in this order on a substrate 1 in an information recording medium. The protective layers 3, 4 are so disposed as to interleave the recording layer 2 therebetween, and the protective layer 5 is so disposed as to prevent damage, dusts on the surface in case of handling the information recording medium. The recording layer 2 is formed of alloy of composition represented by (InxSbyTez)100-alphaMalpha (where x, y, z, alpha are atomic %, x+y+z=100, 400<=x<=60, 2<=y<=27, 23<=z<=47, 0<=alpha<=20, and M is at least one type of element selected from a group consisting of Ti, Zr, Y, W, Ta, Fe and Ni), and satisfactorily formed by a depositing method, a sputtering method, etc.

Description

【発明の詳細な説明】 ［発明の目的］ （産業上の利用分野） この発明は、レーザビーム等の光ビームを記録層に照射
し、その照射条件によって照射部分に相変化を誘起させ
て情報を記録・消去し、この相変化に伴う反射率、透過
率等の光学特性の変化を検出することにより情報を再生
する情報記録媒体に関する。このような情報記録媒体と
しては、光ディスク又は光カード等がある。[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) This invention provides information by irradiating a recording layer with a light beam such as a laser beam and inducing a phase change in the irradiated area depending on the irradiation conditions. The present invention relates to an information recording medium that reproduces information by recording and erasing information and detecting changes in optical properties such as reflectance and transmittance accompanying this phase change. Examples of such information recording media include optical discs and optical cards.

（従来の技術及びその課題） 従来、所謂イレーサブル光ディスク等の情報の消去が可
能な情報記録媒体として、相変化型のものが広く知られ
ている。この相変化型情報記録媒体は、例えば、ガラス
又はプラスチック（ポリカーボネート樹脂、ポリメチル
メタクリレート樹脂等）からなる基板と、この基板上に
形成された記録層とを備えている。この記録層を形成す
る材料としては、例えばＧｅＴｅ等のカルコゲナイド系
合金が知られており、これらは異なる条件の光ビーム（
例えばレーザビーム）を照射することにより、例えば結
晶と非晶質との間で可逆的に相変化するので、この相変
化を利用して情報を記録及び消去し、これらの相変化に
伴う反射率又は透過率等の光学的特性の変化を利用して
情報を読取ることができる。(Prior Art and its Problems) Phase change type media have been widely known as information recording media from which information can be erased, such as so-called erasable optical discs. This phase change type information recording medium includes, for example, a substrate made of glass or plastic (polycarbonate resin, polymethyl methacrylate resin, etc.) and a recording layer formed on the substrate. Chalcogenide alloys such as GeTe are known as materials for forming this recording layer, and these alloys can be used for light beams under different conditions (
By irradiating it with a laser beam (for example, a laser beam), the phase changes reversibly between crystal and amorphous, so this phase change is used to record and erase information, and the reflectance associated with these phase changes is Alternatively, information can be read using changes in optical characteristics such as transmittance.

このような記録層としては、光ビームの照射条件によっ
て相変化が生じ易い共晶組成を有する材料や金属間化合
物を形成する材料が適している。As such a recording layer, a material having a eutectic composition or a material forming an intermetallic compound that easily undergoes a phase change depending on the irradiation conditions of the light beam is suitable.

しかしながら、従来、相変化型情報記録媒体の記録層と
して用いられているＧｅＴｅ等の合金は、一応上述の条
件は満足するものの、未だ情報記録媒体として十分な特
性を保持しているとは言えない。特に、初期化、記録及
び消去を高速化することが望まれている。また、結晶−
非晶質間の相変化により情報を記録・消去する場合には
、通常記録部分が非晶質になるが、一般に非晶質は比較
的安定性が低いため、非晶質状態をより安定化すること
も要求されている。更に、再生特性を一層良好にするこ
とも要求されている。However, although alloys such as GeTe that have been conventionally used as the recording layer of phase change information recording media satisfy the above conditions, it cannot be said that they still have sufficient properties as information recording media. . In particular, it is desired to speed up initialization, recording, and erasing. Also, crystal-
When recording or erasing information through a phase change between amorphous states, the recorded portion usually becomes amorphous, but since amorphous states generally have relatively low stability, it is necessary to make the amorphous state more stable. It is also required to do so. Furthermore, it is also required to have even better reproduction characteristics.

この発明はかかる事情に鑑みてなされたものであって、
初期化、記録及び消去を高速化することができ、記録し
た情報が安定であり、更に再生特性が良好な情報記録媒
体を提供することを目的とする。This invention was made in view of such circumstances, and
It is an object of the present invention to provide an information recording medium that can speed up initialization, recording, and erasing, has stable recorded information, and has good reproduction characteristics.

［発明の構成］ （課題を解決するための手段） この発明に係る情報記録媒体は、基板と、光ビームの照
射によって照射部分が平衡相と非平衡相との間で相変化
する記録層とを有する情報記録媒体であって、前記記録
層は、−数式（ＩｎｘＳｂｙＴｅｚ）＋００−＃　Ｍｅ
　　（ただし、Ｘ。[Structure of the Invention] (Means for Solving the Problems) An information recording medium according to the present invention includes a substrate, a recording layer whose irradiated portion changes phase between an equilibrium phase and a non-equilibrium phase when irradiated with a light beam. The information recording medium has the following: -Math (InxSbyTez)+00-#Me
(However, X.

）’、Ｚ＋　αは原子％、ｘ十ｙ＋ｚ−１００であり、
夫々４０≦Ｘ≦６０．２≦ｙ≦２７．２３≦２≦４７、
Ｏくα≦２０の範囲内にあり、ＭはＴｉ。)', Z + α is atomic %, x 10 y + z - 100,
40≦X≦60.2≦y≦27.23≦2≦47, respectively.
O is within the range of α≦20, and M is Ti.

Ｚｒ、Ｙ、Ｗ、Ｔａ、Ｆｅ、及びＮｉからなる群から選
択される少なくとも１種の元素である）で表される組成
の合金で形成されていることを特徴とする。It is characterized by being formed of an alloy having a composition represented by (at least one element selected from the group consisting of Zr, Y, W, Ta, Fe, and Ni).

（作用） Ｉｎ−８ｂ−Ｔｅ系におイテ Ｉ　ｎ３５ｂＴｅ２　、Ｉ　ｎ［ｓｂ、Ｔｅ７及びＩｎ
４５ｂＴｅ３の組成を有する金属間化合物は、非晶質化
しやすいという利点を有しているので、この組成又はこ
の近傍組成にＭを添加した上述の組成の合金は、前述の
ような相変化型記録媒体の記録層としての条件を満たす
材料である。また、上述のＭで示される元素は、２０原
子％よりも低い範囲で含有させることによりＩｎ−８ｂ
−Ｔｅの非晶質状態を安定化し、また、結晶化の際の核
発生の頻度が高いため初期結晶化に伴うノイズが低くな
るという利点を有する。更に、上述の組成の材料は結晶
化速度が大きい。従って、非晶質状態として記録された
情報の安定化、並びに初期化、記録及び消去の高速化を
達成することができ、更に再生特性を良好にすることが
できる。(Action) In-8b-Te system In-8bTe2, In[sb, Te7 and In
An intermetallic compound having a composition of 45bTe3 has the advantage of being easily amorphous, so an alloy with the above-mentioned composition in which M is added to this composition or a composition close to this composition can be used for phase change recording as described above. It is a material that satisfies the conditions for a recording layer of a medium. In addition, by containing the element represented by M in a range lower than 20 at%, In-8b
It has the advantage that it stabilizes the amorphous state of -Te, and that the noise accompanying the initial crystallization is reduced because the frequency of nucleation during crystallization is high. Furthermore, materials with the above-mentioned compositions have a high crystallization rate. Therefore, it is possible to stabilize information recorded in an amorphous state and to speed up initialization, recording, and erasing, and it is also possible to improve reproduction characteristics.

（実施例） 以下、添付図面を参照してこの発明について具体的に説
明する。第１図はこの発明の実施例に係る情報記録媒体
を示す断面図である。基板１はポリオレフィン、エポキ
シ、ポリカーボネート（ＰＣ）、ポリメチルメタクリレ
ート（ＰＭＭＡ）等のプラスチック、又はガラス等、こ
の技術分野で通常用いられる材料で形成されてい、る。(Example) Hereinafter, the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a sectional view showing an information recording medium according to an embodiment of the invention. The substrate 1 is made of a material commonly used in this technical field, such as a plastic such as polyolefin, epoxy, polycarbonate (PC), polymethyl methacrylate (PMMA), or glass.

この基板１の上に、保護層３、記録層２、保護層４及び
保護層５がこの順に形成されている。On this substrate 1, a protective layer 3, a recording layer 2, a protective layer 4, and a protective layer 5 are formed in this order.

保護層３及び保護層４は、記録層２を挟むように配設さ
れており、有機高分子材料、例えばＰＭＭＡ、ポリスチ
レン等の熱可塑性樹脂若しくは紫外線硬化樹脂（所謂２
Ｐ樹脂）、又はＳ　ｉ０２　、Ａ１２０３　、ＡｌＮ５
ＺｎＳ、若しくはＺｒＯ２等の誘電体で形成される。こ
れら保護層３．４は記録層２が空気中の水分の影響を受
けることを未然に防止する作用、及び記録・消去の際に
レーザビーム等の光ビームにより記録層２の照射部分が
飛散したり穴が形成されてしまうことを防止する作用を
有している。これら保護層３゜４はスピンコード法、蒸
着法、スパッタリング法等によって好適に形成すること
ができる。なお、これら保護層３．４の厚みは１０入乃
至数十μｍであることが好ましい。The protective layer 3 and the protective layer 4 are disposed to sandwich the recording layer 2 and are made of an organic polymer material, such as a thermoplastic resin such as PMMA or polystyrene, or an ultraviolet curing resin (so-called 2
P resin), or S i02 , A1203 , AlN5
It is formed of a dielectric material such as ZnS or ZrO2. These protective layers 3.4 serve to prevent the recording layer 2 from being affected by moisture in the air, and to prevent the irradiated portion of the recording layer 2 from being scattered by a light beam such as a laser beam during recording or erasing. It has the effect of preventing the formation of holes. These protective layers 3 and 4 can be suitably formed by a spin coating method, a vapor deposition method, a sputtering method, or the like. Note that the thickness of these protective layers 3.4 is preferably 10 μm to several tens of μm.

保護層５は情報記録媒体取扱う際の表面での傷やほこり
等を防止するために配設されるもので、スピンコード法
等により紫外線硬化樹脂を塗布し、これに紫外線を照射
して硬化させること等により形成される。この保護層５
の層厚は１００入乃至数十μｍであることが好ましい。The protective layer 5 is provided to prevent scratches, dust, etc. on the surface when handling the information recording medium, and is coated with an ultraviolet curing resin using a spin code method or the like, and then cured by irradiating it with ultraviolet light. It is formed by such things as This protective layer 5
The layer thickness is preferably from 100 μm to several tens of μm.

なお、保護層３゜４．５は設けることが好ましいが、必
ずしも設けなくてもよい。Although it is preferable to provide the protective layer 3°4.5, it is not necessary to provide it.

記録層２は、（ＩｎｘＳｂｙＴｅｚ）ｔｏｏ−、Ｍａ（
ただし、ｘ、ｙ、ｚ、αは原子％、）（＋ｙ十ｚ−１０
０であり、夫々４０≦Ｘ≦６０．２≦ｙ≦２７．２３≦
２≦４７．０くα≦２０の範囲内にあり、ＭはＴｉ、Ｚ
ｒ、Ｙ、Ｗ、Ｔａ、Ｆｅ、及びＮｉからなる群から選択
される少なくとも１種の元素である）で表される組成の
合金で形成されており、蒸着法、スパッタリング法等に
よって好適に形成することができる。なお、合金ターゲ
ットを使用して蒸着又はスパッタリングする場合には、
ターゲット組成と実際に形成される膜の組成とに差があ
ることを考慮する必要がある。また、多元同時蒸着又は
多元同時スパッタリング等によって成膜することもでき
る。記録層２の層厚は１００乃至３０００Åであること
が好ましい。The recording layer 2 has (InxSbyTez)too-, Ma(
However, x, y, z, α are atomic %, )(+y + z-10
0, respectively 40≦X≦60.2≦y≦27.23≦
2≦47.0 and α≦20, M is Ti, Z
r, Y, W, Ta, Fe, and Ni), and is preferably formed by a vapor deposition method, a sputtering method, etc. can do. In addition, when performing vapor deposition or sputtering using an alloy target,
It is necessary to consider that there is a difference between the target composition and the composition of the film actually formed. Further, the film can also be formed by multi-source simultaneous vapor deposition, multi-source simultaneous sputtering, or the like. The thickness of the recording layer 2 is preferably 100 to 3000 Å.

記録層２を構成する （ＩｎｘＳｂｙＴｅｚ）１００−５Ｍ、は、照射する光
ビームの条件を変えることにより平衡相と非平衡相（非
晶質相、準安定結晶相等）との間で相変化し得る材料で
あり、Ｉｎ、Ｓｂ、及びＴｅが非晶質化しやすい金属間
化合物１　ｎ３５ｂＴｅ２　。(InxSbyTez) 100-5M, which constitutes the recording layer 2, can undergo a phase change between an equilibrium phase and a nonequilibrium phase (amorphous phase, metastable crystalline phase, etc.) by changing the conditions of the irradiated light beam. In, Sb, and Te are intermetallic compounds that easily become amorphous.

Ｉｎｌ　ＯＳｂ３　Ｔｅ７及びＩ　ｎ４５ｂＴｅ３の近
傍組成であることから非平衡相としての非晶質状態の安
定性が優れている。また、結晶化速度が大きく、非晶質
化しやすいことから初期化、記録及び消去速度が大きい
。更に、再生信号のノイズが小さい。Since the composition is close to that of Inl OSb3 Te7 and In45bTe3, the stability of the amorphous state as a non-equilibrium phase is excellent. In addition, since the crystallization speed is high and it is easy to become amorphous, the initialization, recording and erasing speeds are high. Furthermore, the noise of the reproduced signal is small.

次に、第２図及び第３図を参照しながらこの実施例に係
る情報記録媒体の記録層の形成方法の一例について説明
する。第２図はこの実施例の記録層を形成するために用
いられるスパッタリング装置の概略構成を示す縦断面図
、第３図はその横断面図である。図中１０は真空容器を
示し、この真空容器１０はその底面にガス導入ボート１
１及びガス排出ボート１２を有している。ガス排出ボー
ト１２は排気装置１３に接続されており、この排気装置
１３により排出ボート１２を介して真空容器１０内が排
気される。また、ガス導入ボート１１はアルゴンガスボ
ンベ１４に接続されており、このボンベ１４から真空容
器１０内にガス導入ボート１１を介してスパッタリング
ガスとしてのアルゴンガスが導入される。真空容器１０
内の上部には、基板支持用の円板状の回転基台１５がそ
の面を水平にして配設されており、その下面に基板１が
支持され、図示しないモータによって回転されるように
なっている。また、真空容器１０内の底部近傍には、基
台１５に対向するように、夫々記録層の構成する所定元
素で形成されたスパッタリング源２１，２２．２３が配
設されており、各スパッタリング源には図示しない高周
波電源が接続されている。これらスパッタリング源２１
゜２２．２３の上方には、夫々モニタ装置２４゜２５．
２６が設けられており、これらモニタ装置により各スパ
ッタリング源からのスパッタリング量をモニタし、記録
層が所定の組成になるように各スパッタリング源に投入
する電力量を調節するようになっている。Next, an example of a method for forming the recording layer of the information recording medium according to this embodiment will be explained with reference to FIGS. 2 and 3. FIG. 2 is a longitudinal cross-sectional view showing a schematic configuration of a sputtering apparatus used to form the recording layer of this embodiment, and FIG. 3 is a cross-sectional view thereof. In the figure, 10 indicates a vacuum vessel, and this vacuum vessel 10 has a gas introduction boat 1 on its bottom surface.
1 and a gas discharge boat 12. The gas exhaust boat 12 is connected to an exhaust device 13, and the inside of the vacuum container 10 is evacuated by the exhaust device 13 via the exhaust boat 12. Further, the gas introduction boat 11 is connected to an argon gas cylinder 14, and argon gas as a sputtering gas is introduced from the cylinder 14 into the vacuum vessel 10 via the gas introduction boat 11. Vacuum container 10
A disk-shaped rotating base 15 for supporting a substrate is placed in the upper part thereof with its surface horizontally, and the substrate 1 is supported on the lower surface thereof and is rotated by a motor (not shown). ing. Furthermore, near the bottom of the vacuum vessel 10, sputtering sources 21, 22, and 23, each made of a predetermined element constituting the recording layer, are arranged so as to face the base 15. A high frequency power source (not shown) is connected to. These sputtering sources 21
Above 22.23°, monitor devices 24°25.
26, these monitoring devices monitor the amount of sputtering from each sputtering source, and adjust the amount of power input to each sputtering source so that the recording layer has a predetermined composition.

このようなスパッタリング装置においては、先ず、排気
装置により真空容器１０内を例えば１０＝Ｔｏｒｒまで
排気する。次いで、ガス導入ボート１１を介して容器１
０内にアルゴンガスを導入しつつ、排気装置１３の排気
量を調節して真空容器１０内を所定圧力のアルゴンガス
雰囲気に保持する。この状態で、基板１を回転させつつ
、スパッタリング源２１．２２．２３に所定時間所定の
電力を印加する。これにより、基板１に所定組成の記録
層が形成される。なお、保護層を形成する場合には、記
録層２の形成に先立ち、保護層の組成に調整されたスパ
ッタリング源を用いて上述したようにスパッタリングす
るこにより基板１上に保護層３を形成し、その後記録層
２を形成し、更に保護層３を形成する場合と同様の条件
で記録層２の上に保護層４を形成することができる。In such a sputtering apparatus, first, the inside of the vacuum container 10 is evacuated to, for example, 10 Torr using an exhaust device. Next, the container 1 is introduced via the gas introduction boat 11.
While introducing argon gas into the vacuum container 10, the exhaust amount of the exhaust device 13 is adjusted to maintain the interior of the vacuum container 10 in an argon gas atmosphere at a predetermined pressure. In this state, while rotating the substrate 1, a predetermined power is applied to the sputtering sources 21, 22, and 23 for a predetermined time. As a result, a recording layer having a predetermined composition is formed on the substrate 1. Note that when forming the protective layer, prior to forming the recording layer 2, the protective layer 3 is formed on the substrate 1 by sputtering as described above using a sputtering source adjusted to the composition of the protective layer. Then, the recording layer 2 is formed, and the protective layer 4 can be formed on the recording layer 2 under the same conditions as in the case of forming the protective layer 3.

次に、この発明の情報記録媒体における初期化、並びに
、情報の記録、消去及び再生について説明する。Next, initialization, recording, erasing, and reproduction of information in the information recording medium of the present invention will be explained.

初期化 記録層２は成膜直後に通常非晶質であるが、情報を記録
するためには結晶である必要があるので、レーザビーム
等の光ビームを記録層２に全面照射して加熱徐冷し、記
録層２を結晶化する。The initialization recording layer 2 is normally amorphous immediately after film formation, but it needs to be crystalline in order to record information, so the recording layer 2 is heated and slowed by irradiating the entire surface of the recording layer 2 with a light beam such as a laser beam. Cool and crystallize the recording layer 2.

記録 高出力でパルス幅が短い光ビームを記録層２に照射し、
照射部分を加熱急冷して非晶質に相変化させ、記録マー
クを形成する。A light beam with high recording power and short pulse width is irradiated onto the recording layer 2,
The irradiated area is heated and rapidly cooled to change its phase to an amorphous state, thereby forming a recording mark.

消去 記録層２に形成された記録マーク部に、記録の際よりも
低出力でパルス幅が長い光ビームを照射して記録マーク
部を結晶に相変化させ、情報を消去する。A light beam having a lower output and a longer pulse width than that used during recording is irradiated onto the recording mark portion formed on the erasing recording layer 2 to change the phase of the recording mark portion into a crystal, thereby erasing information.

再生 情報を記録した記録層２に比較的弱い光ビームを照射し
、記録マーク部と非記録部との間の光学的特性、例えば
反射率の差を検出して情報を読取る。A relatively weak light beam is irradiated onto the recording layer 2 on which reproduced information has been recorded, and the information is read by detecting the difference in optical characteristics, such as reflectance, between the recorded mark portion and the non-recorded portion.

なお、この発明に係る情報記録媒体は、結晶化速度が大
きいことからオーバーライドが可能である。オーバーラ
イドとは、単一の光源から放射されるレーザビーム等の
光ビームを、第４図に示すように２段階のパワーレベル
ＰＥ　　（消去）及びＰｗ　　（記録）の間でパワー変
調して、消去パワーレベルの光ビームに記録パワーレベ
ルのパルスを１１１畳させ、既に記録された情報を消去
しながら新しい情報を重ね書きすることである。In addition, since the information recording medium according to the present invention has a high crystallization speed, overriding is possible. Overriding is erasing by power modulating a light beam such as a laser beam emitted from a single light source between two power levels PE (erasing) and Pw (recording) as shown in Figure 4. This involves applying 111 pulses at a recording power level to a light beam at a power level, and overwriting new information while erasing already recorded information.

次に、この発明の試験例について説明する。Next, test examples of the present invention will be explained.

試験例１ 耐熱ガラス基板上に、第２図及び第３図に示すスパッタ
リング装置により、種々の組成のＩ　ｎ　ｘ　Ｓ　ｂ　
ｙ　Ｔ　ｅ　ｚ合金薄膜を形成し、Ｘ線回折によりこれ
ら薄膜の構造を確認した。第５図の３元系組成図におい
て斜線で示す範囲、すなわち４０≦Ｘ≦６０．２≦ｙ≦
２７．２３≦２≦４７の組成範囲で確認した結果、いず
れも成膜直後に非晶質であった。この組成範囲において
、非晶質化しやすい金属間化合物としてＩ　ｎ３５ｂＴ
ｅ２　。Test Example 1 I n x S b of various compositions were deposited on a heat-resistant glass substrate using the sputtering apparatus shown in FIGS. 2 and 3.
yTez alloy thin films were formed, and the structures of these thin films were confirmed by X-ray diffraction. The range indicated by diagonal lines in the ternary composition diagram in Figure 5, that is, 40≦X≦60.2≦y≦
As a result of confirmation in the composition range of 27.23≦2≦47, all of them were amorphous immediately after film formation. In this composition range, I n35bT is an intermetallic compound that easily becomes amorphous.
e2.

Ｉｎ＠５ｂ３Ｔｅ７及びＩｎ４ＳｂＴｅ３が知られてい
るが、上述のように、これら金属間化合物の近傍組成に
おいても非晶質状態をとり得ることができ、レーザビー
ムの照射条件を選択することにより記録・消去する相変
化型の記録層として利用し得ることが確認された。In@5b3Te7 and In4SbTe3 are known, but as mentioned above, these intermetallic compounds can have an amorphous state even in the vicinity of their composition, and can be recorded and erased by selecting the laser beam irradiation conditions. It was confirmed that it can be used as a phase change type recording layer.

試験例２ 試験例１の組成範囲のＩ　ｎ　ｘ　Ｓ　ｂ　ｙ　Ｔ　ｅ
　ｚに対して、Ｔｉ、Ｚｒ、Ｙ、Ｗ、Ｔａ、Ｆｅ、及び
Ｎｉを各々添加したサンプルを作成した。その結果、い
ずれのサンプルにおいても、結晶化温度の増加を示した
。Test Example 2 In x S by T e in the composition range of Test Example 1
Samples were prepared in which Ti, Zr, Y, W, Ta, Fe, and Ni were added to Z. As a result, all samples showed an increase in crystallization temperature.

これらの元素は、いずれも融点が高い材料であり、Ｔｉ
が１６７２℃、Ｚ「が１８６５℃、Ｙが１５２８℃、Ｗ
が３３８７℃、Ｔａが３０２０℃、Ｆｅが１５３８℃、
ＮＬが１４５５℃である。結晶化温度は、通常、非晶質
合金の絶対温度で示した融点の１／２〜２／３の温度と
なることが知られているから、これら元素の添加により
合金の融点が増加し、それに伴い結晶化温度が増加した
ものと考えられる。このように、Ｔｉ、Ｚｒ、Ｙ。All of these elements are materials with high melting points, and Ti
is 1672℃, Z is 1865℃, Y is 1528℃, W
is 3387℃, Ta is 3020℃, Fe is 1538℃,
NL is 1455°C. It is known that the crystallization temperature is usually 1/2 to 2/3 of the absolute melting point of an amorphous alloy, so the addition of these elements increases the melting point of the alloy. It is considered that the crystallization temperature increased accordingly. In this way, Ti, Zr, Y.

Ｗ、Ｔａ、Ｆｅ、及びＮｉはＩ　ｎ　ｘ　Ｓ　ｂ　ｙ　
Ｔ　ｅ　ｚの非晶質状態を安定化させる効果があること
が確認された。W, Ta, Fe, and Ni are In x S by
It was confirmed that there is an effect of stabilizing the amorphous state of T ez.

試験例３ 試験例２で作成したサンプルに対し、照射条件を変えな
がら基板側からレーザビームを照射し、結晶化速度を調
べた。第６図にＴｉを夫々５゜１０．２０．３０原子％
添加したサンプルにおける結果について示す。第６図は
横軸に照射するレーザビームのパルス幅をとり、縦軸に
反射率変化量をとって、これらの関係を示すグラフであ
る。Test Example 3 The sample prepared in Test Example 2 was irradiated with a laser beam from the substrate side while changing the irradiation conditions, and the crystallization rate was examined. Figure 6 shows Ti at 5°, 10, 20, and 30 atomic %, respectively.
The results for the added samples are shown below. FIG. 6 is a graph showing the relationship between these, with the horizontal axis representing the pulse width of the irradiated laser beam and the vertical axis representing the amount of change in reflectance.

このグラフにおいて、反射率の変化が非晶質と結晶との
間の相変化に対応する。なお、第６図は照射スるレーザ
ビームのパワーが７ｍＷの場合である。この第６図に示
すように、Ｔｉが無添加の場合に比較し、Ｔｉ５％では
結晶化速度が速くなり、１０％、２０％では逆に結晶化
速度が低下した。In this graph, changes in reflectance correspond to phase changes between amorphous and crystalline. Note that FIG. 6 shows a case where the power of the irradiated laser beam is 7 mW. As shown in FIG. 6, compared to the case where no Ti was added, the crystallization rate increased at 5% Ti, and conversely decreased at 10% and 20% Ti.

更に、Ｔｉ３０％では結晶化速度が１８ｍ５ｅｃ以上と
なり、反射率の変化量も大きく減少した。これはＴｉの
添加により融点が増加するため、相変化に要するエネル
ギが増加したためと考えられる。Furthermore, with 30% Ti, the crystallization rate was 18 m5ec or more, and the amount of change in reflectance was also significantly reduced. This is considered to be because the addition of Ti increases the melting point, which increases the energy required for phase change.

実用性を考えると結晶化速度が１μｍ５ｅｃ以下が望ま
しいので、Ｔｉの添加量としては２０原子％以下が適当
である。Considering practicality, it is desirable that the crystallization rate be 1 μm 5 ec or less, so the amount of Ti added is suitably 20 atomic % or less.

Ｔｉの代りに、Ｚｎ、Ｙ、Ｗ、Ｔａ、Ｆｅ及びＮｉを夫
々添加した合金を形成したサンプルについて同様の試験
を行なった結果、同様な結果が得られ、これらについて
も実用上添加量が２０％以下が適当であることが確認さ
れた。Similar tests were conducted on alloy samples in which Zn, Y, W, Ta, Fe, and Ni were added instead of Ti, and similar results were obtained. % or less was confirmed to be appropriate.

また、これらの元素は、いくつか組合わせて添加しても
同様の効果を得ることができる。この場合にもトータル
添加量が２０％を超えると記録感度が低下するので、実
用上２０％以下が適当である。Moreover, the same effect can be obtained even if some of these elements are added in combination. In this case as well, if the total amount added exceeds 20%, the recording sensitivity decreases, so 20% or less is practically appropriate.

試験例４ 試験例１の組成範囲内のＩ　ｎ　ｘ　Ｓ　ｂ　ｙ　Ｔ　
ｅ　ｚに対してＴｉ、Ｚｒ、Ｙ、Ｗ、Ｔａ、Ｆｅ、及び
Ｎｉを夫々５％添加した合金を記録層とし、第１図に示
す層構成のディスクサンプルを作成した。Test Example 4 In x S by T within the composition range of Test Example 1
A disk sample having the layer structure shown in FIG. 1 was prepared using an alloy containing 5% each of Ti, Zr, Y, W, Ta, Fe, and Ni as a recording layer.

このディスクを一定の回転数で回転させて、一定の半径
位置に１１ｍＷのレーザビームを照射して一つのトラッ
クを初期化した。その際の再生信号のノイズレベルをス
ペクトロアナライザにて測定した。また、比較のために
これらの元素を添加しないＩ　ｎ　ｘ　Ｓ　ｂ　ｙ　Ｔ
　ｅ　ｚを記録層とした以外は同様に構成されたサンプ
ルについても同様に試験した。その結果を第７図に示す
。第７図は、横軸に周波数とり、縦軸にノイズレベルを
とって、これらの間の関係を示すグラフである。なお、
バンド幅は３０ｋＨｚとした。この第７図に示すように
、Ｔｉ等を添加しないＩ　ｎ　ｘ　Ｓ　ｂ　ｙ　Ｔ　ｅ
　ｚ合金を記録層として用いたサンプルについては、初
期化することにより低周波数側のノイズレベルが大きく
増加しているが、記録層にＴ　ｔ、Ｚ　ｒ、Ｙ、Ｗ。This disk was rotated at a constant rotation speed, and a laser beam of 11 mW was irradiated to a constant radial position to initialize one track. The noise level of the reproduced signal at that time was measured using a spectroanalyzer. Also, for comparison, In x S b y T without adding these elements
Samples having the same structure except that ez was used as the recording layer were also tested in the same manner. The results are shown in FIG. FIG. 7 is a graph showing the relationship between frequency on the horizontal axis and noise level on the vertical axis. In addition,
The bandwidth was 30kHz. As shown in FIG. 7, In x S b y T e without adding Ti, etc.
Regarding the sample using Z alloy as the recording layer, the noise level on the low frequency side increased significantly after initialization, but the recording layer contains T t, Z r, Y, and W.

Ｔａ、Ｆｅ、及びＮｉを添加したサンプルでは、ノイズ
レベルの低下が確認された。It was confirmed that the noise level was reduced in the samples to which Ta, Fe, and Ni were added.

初期化した後のトラックを透過型電子顕微鏡で観察した
結果、記録層にＴｉ等を添加しないサンプルでは、初期
化したトラックにおいて結晶粒が粗大化していることが
確認された。これに対し、記録層にＴｉ等を添加したサ
ンプルにおいては、無添加のサンプルに比較して結晶粒
が微細であった。As a result of observing the initialized track with a transmission electron microscope, it was confirmed that in the sample in which Ti or the like was not added to the recording layer, the crystal grains in the initialized track were coarsened. On the other hand, in the sample in which Ti or the like was added to the recording layer, the crystal grains were finer than in the sample in which no additive was added.

この結果から、Ｉ　ｎ　ｘ　Ｓ　ｂ　ｙ　Ｔ　ｅ　ｚに
対してＴｉ等を添加することにより、初期化の際の結晶
粒が微細化し、これによりノイズレベルが低下したもの
と考えられる。From this result, it is considered that by adding Ti or the like to In x S by T e z, the crystal grains during initialization were made finer, thereby reducing the noise level.

以上の結果から、上述の範囲の （Ｉ　ｎｘ　ＳｂｙＴｅｚ）１００−ｇ　Ｍ、合金を相
変化型の記録層として使用することが可能なこと、この
ような記録層はＭ元素の添加に伴って非晶質状態の安定
性が増加すること、結晶化速度が１μｍ　ｓｅｃ以下と
高速であること、及びＭ元素の存在により結晶粒を微細
化してノイズを低下することができることが確認された
。From the above results, it is possible to use (I nx SbyTez) 100-g M alloy in the above range as a phase-change type recording layer, and that such a recording layer becomes non-resistant with the addition of M element. It was confirmed that the stability of the crystalline state increases, that the crystallization speed is as high as 1 μm sec or less, and that the presence of the M element makes it possible to refine crystal grains and reduce noise.

なお、この実施例においては基板として平板状のものを
使用した例について示したが、これに限らず、テープ状
、又はドラム状等種々の形態をとることが可能である。In this embodiment, a flat plate-shaped substrate is used as the substrate, but the substrate is not limited to this, and various forms such as a tape-shaped or a drum-shaped substrate can be used.

［発明の効果］ この発明によれば、非晶質化しやすい金属間化合物Ｉ　
ｎ３５ｂＴｅ２　、Ｉ　ｎ［５ｂ３Ｔｅ７及びＩｎ４５
ｂＴｅ３の近傍組成に比較的高融点のＭ元素を添加して
記録層を形成したので、非平衡相である非晶質状態の記
録マークの安定性に優れ、また初期化、記録及び消去を
高速で実施することができ、更に信号ノイズが小さいと
いう極めて特性が優れた情報記録媒体を得ることができ
る。[Effect of the invention] According to this invention, intermetallic compound I that is easily amorphous
n35bTe2, In[5b3Te7 and In45
Since the recording layer was formed by adding M element with a relatively high melting point to the composition near bTe3, the recording mark in the amorphous state, which is a non-equilibrium phase, has excellent stability, and initialization, recording, and erasing can be performed at high speed. Furthermore, it is possible to obtain an information recording medium with extremely excellent characteristics such as low signal noise.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図はこの発明の実施例に係る情報記録媒体を示す断
面図、第２図は記録層を形成するための装置の概略構成
を示す縦断面図、第３図はその横断面図、第４図はオー
バーライドの際のレーザビームのパワーを示す図、第５
図はこの発明に係る情報記録媒体の記録層の基本となる
Ｉｎ−３ｂ−Ｔｅ３元合金の組成範囲を示す組成図、第
６図は照射するレーザビームのパルス幅と反射率変化量
との関係を示すグラフ図、第７図は周波数と媒体ノイズ
レベルとの関係を示すグラフ図である。 １　； 基板、 ２　； 記録層、 ３゜ ４゜ ５　； 保護層。FIG. 1 is a cross-sectional view showing an information recording medium according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view showing a schematic configuration of an apparatus for forming a recording layer, and FIG. Figure 4 shows the power of the laser beam during override, Figure 5
The figure is a composition diagram showing the composition range of the In-3b-Te ternary alloy that is the basis of the recording layer of the information recording medium according to the present invention, and Figure 6 is the relationship between the pulse width of the irradiated laser beam and the amount of change in reflectance. FIG. 7 is a graph showing the relationship between frequency and medium noise level. 1: Substrate, 2: Recording layer, 3゜4゜5: Protective layer.

Claims (1)

【特許請求の範囲】[Claims] 基板と、光ビームの照射によって照射部分が平衡相と非
平衡相との間で相変化する記録層とを有する情報記録媒
体であって、前記記録層は、一般式（Ｉｎ＿ｘＳｂ＿ｙ
Ｔｅ＿ｚ）＿１＿０＿０＿−＿αＭ＿α（ただし、ｘ、
ｙ、ｚ、αは原子％、ｘ＋ｙ＋ｚ＝１００であり、夫々
４０≦ｘ≦６０、２≦ｙ≦２７、２３≦ｚ≦４７、０＜
α≦２０の範囲内にあり、ＭはＴｉ、Ｚｒ、Ｙ、Ｗ、Ｔ
ａ、Ｆｅ、及びＮｉからなる群から選択される少なくと
も１種の元素である）で表される組成の合金で形成され
ていることを特徴とする情報記録媒体。An information recording medium comprising a substrate and a recording layer whose irradiated portion changes phase between an equilibrium phase and a non-equilibrium phase by irradiation with a light beam, the recording layer having the general formula (In_xSb_y
Te_z)_1_0_0_−_αM_α(However, x,
y, z, α are atomic %, x+y+z=100, respectively 40≦x≦60, 2≦y≦27, 23≦z≦47, 0<
α≦20, M is Ti, Zr, Y, W, T
1. An information recording medium characterized in that it is formed of an alloy having a composition represented by (at least one element selected from the group consisting of a, Fe, and Ni).
JP63322078A 1988-12-22 1988-12-22 Information recording medium Pending JPH02167788A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP63322078A JPH02167788A (en) 1988-12-22 1988-12-22 Information recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63322078A JPH02167788A (en) 1988-12-22 1988-12-22 Information recording medium

Publications (1)

Publication Number Publication Date
JPH02167788A true JPH02167788A (en) 1990-06-28

Family

ID=18139672

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63322078A Pending JPH02167788A (en) 1988-12-22 1988-12-22 Information recording medium

Country Status (1)

Country Link
JP (1) JPH02167788A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200083445A1 (en) * 2018-09-07 2020-03-12 Korea Institute Of Science And Technology Four-or-more-component-based chalcogenide phase-change material and memory device comprising the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200083445A1 (en) * 2018-09-07 2020-03-12 Korea Institute Of Science And Technology Four-or-more-component-based chalcogenide phase-change material and memory device comprising the same
US10700278B2 (en) * 2018-09-07 2020-06-30 Korea Institute Of Science And Technology Four-or-more-component-based chalcogenide phase-change material and memory device comprising the same

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