JPH0481951B2 - - Google Patents
Info
- Publication number
- JPH0481951B2 JPH0481951B2 JP61143383A JP14338386A JPH0481951B2 JP H0481951 B2 JPH0481951 B2 JP H0481951B2 JP 61143383 A JP61143383 A JP 61143383A JP 14338386 A JP14338386 A JP 14338386A JP H0481951 B2 JPH0481951 B2 JP H0481951B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- selenium
- substrate
- tellurium
- optical recording
- 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.)
- Expired - Lifetime
Links
- 239000011669 selenium Substances 0.000 claims description 21
- 230000003287 optical effect Effects 0.000 claims description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 16
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 claims description 16
- 229910052711 selenium Inorganic materials 0.000 claims description 16
- 239000000758 substrate Substances 0.000 claims description 15
- 229910052714 tellurium Inorganic materials 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 10
- PORWMNRCUJJQNO-UHFFFAOYSA-N tellurium atom Chemical compound [Te] PORWMNRCUJJQNO-UHFFFAOYSA-N 0.000 claims description 8
- -1 tellurium selenide Chemical class 0.000 description 4
- 229910001370 Se alloy Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 229920000178 Acrylic resin Polymers 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229920000515 polycarbonate Polymers 0.000 description 2
- 239000004417 polycarbonate Substances 0.000 description 2
- 229920000647 polyepoxide Polymers 0.000 description 2
- 239000011116 polymethylpentene Substances 0.000 description 2
- 229920000306 polymethylpentene Polymers 0.000 description 2
- 229920000098 polyolefin Polymers 0.000 description 2
- 229920003002 synthetic resin Polymers 0.000 description 2
- 239000000057 synthetic resin Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 229910052798 chalcogen Inorganic materials 0.000 description 1
- 150000001787 chalcogens Chemical class 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 230000015654 memory Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
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
- G11B7/2433—Metals or elements of Groups 13, 14, 15 or 16 of the Periodic Table, e.g. B, Si, Ge, As, Sb, Bi, Se or Te
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/242—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)
-
- 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
- G11B2007/24318—Non-metallic elements
- G11B2007/24322—Nitrogen
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
- G11B7/253—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates
- G11B7/2533—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates comprising resins
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Thermal Transfer Or Thermal Recording In General (AREA)
- Optical Record Carriers And Manufacture Thereof (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明はレーザ光によつて情報を記録再生する
ことのできる光記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording medium on which information can be recorded and reproduced using laser light.
［従来の技術］
レーザ光によつて情報を媒体に記録し、かつ再
生する光デイスクメモリは、記録密度が高いこと
から大容量記録装置として優れた特徴を有してい
る。この光記録媒体材料としては、テルル（Te）
等のカルコゲン元素又はこれらの化合物が使用さ
れている（特公昭47−26897号公報）。とくにテル
ルーセレン系合金はよく使用されている（特公昭
54−41902号公報、特公昭57−7919号公報、特公
昭57−56058号公報）。[Prior Art] Optical disk memories, which record and reproduce information on a medium using laser light, have excellent characteristics as large-capacity recording devices because of their high recording density. The material for this optical recording medium is tellurium (Te).
Chalcogen elements such as or compounds thereof are used (Japanese Patent Publication No. 47-26897). In particular, tellurium selenium alloys are often used (Tokuko Sho
54-41902, Japanese Patent Publication No. 57-7919, Japanese Patent Publication No. 57-56058).
近年、記録装置を小型化するため、レーザ光源
としては半導体レーザが使用されてきている。半
導体レーザは発振波長が8000Å前後であるが、テ
ルルーセレン係合金はこの波長帯にも比較的よく
適合し、適度な反射率と適度な吸収率が得られる
｛フイジカ・ステイタス・ソリダイ，７、189、
1964（phys.stat.sol.７、189、1964）｝。 In recent years, in order to downsize recording devices, semiconductor lasers have been used as laser light sources. Semiconductor lasers have an oscillation wavelength of around 8000 Å, and tellurium selenide alloys are relatively well suited to this wavelength range, and can provide moderate reflectance and moderate absorption {Physica Status Solidai, 7 , 189,
1964 (phys.stat.sol. 7 , 189, 1964)}.
このテルルーセレン系合金を光記録層として用
いた光記録媒体は第２図に示すような構成になつ
ている。すなわち基板１に隣接してテルルーセレ
ン系合金よりなる記録層２１が設けられている。
記録用レーザ光は基板１を通して記録層２１に集
光照射され、ピツト２２が形成される。基板１と
してはポリカーボネート、ポリオレフイン、ポリ
メチルペンテン、アクリル、エポキシ樹脂等の合
成樹脂やガラスが使用され、基板１にはピツトが
同心円状あるいはスパイラル状に一定間隔で精度
よく記録されるように通常案内溝が設けられてい
る。 An optical recording medium using this telluroselenium alloy as an optical recording layer has a structure as shown in FIG. That is, a recording layer 21 made of a tellurium selenium alloy is provided adjacent to the substrate 1 .
The recording laser beam is focused and irradiated onto the recording layer 21 through the substrate 1, and pits 22 are formed. The substrate 1 is made of synthetic resin such as polycarbonate, polyolefin, polymethylpentene, acrylic, or epoxy resin, or glass, and is usually guided so that pits are recorded concentrically or spirally at regular intervals. A groove is provided.
レーザビーム径程度の幅の光が入射すると光は
回折され、ビーム中心が溝からずれるにつれて回
折光強度の空間分布が変化するので、これを検出
してレーザビームを溝の中心に入射させるように
サーボ系が構成されている。溝の幅は通常0.3〜
1.3μmであり、溝の深さは使用するレーザ波長の
１／１２から1/4の範囲に設定される。集光に関して
も同様にサーボ系が構成されている。情報の読み
出しは、記録のときよりも弱いパワーのレーザ光
をピツト上を通過するように照射することによ
り、ピツトの有無に起因する反射率の変化を検出
して行なう。この再生用レーザ光のパワーは大き
いほうが、再生信号やサーボ用信号を大きくでき
外界ノイズの影響をうけにくいので望ましい。 When light with a width similar to the diameter of the laser beam is incident, the light is diffracted, and as the beam center shifts from the groove, the spatial distribution of the diffracted light intensity changes.This is detected and the laser beam is directed to the center of the groove. A servo system is configured. Groove width is usually 0.3~
The groove depth is set to 1/12 to 1/4 of the wavelength of the laser used. A servo system is similarly configured for condensing light. Information is read by irradiating a laser beam with a power weaker than that used during recording so as to pass over the pits, and detecting changes in reflectance caused by the presence or absence of pits. It is desirable that the power of this reproducing laser beam be large, since this allows the reproduction signal and servo signal to be increased and is less susceptible to external noise.
［発明が解決しようとする問題点］
しかしながら、前記したような従来の光記録媒
体において、記録層として用いられているテルル
ーセレン系合金はその組成を制御することが容易
ではなく、そのため量産性に問題があつた。また
充分に良好な記録再生特性は得られなかつた。[Problems to be Solved by the Invention] However, in the conventional optical recording media as described above, it is not easy to control the composition of the tellurium selenium alloy used as the recording layer, which poses problems in mass production. It was hot. Furthermore, sufficiently good recording and reproducing characteristics could not be obtained.
一方、本発明者らは、基板の上にセレン層、テ
ルル層、セレン層を順次積層して記録層とするこ
とにより、量産性および耐侯性に優れ、かつ高感
度で良好な記録再生特性を有する光記録媒体とな
ることを見出し、すでに提案している。 On the other hand, the present inventors succeeded in laminating a selenium layer, a tellurium layer, and a selenium layer on a substrate to form a recording layer, thereby achieving excellent mass productivity and weather resistance, as well as high sensitivity and good recording and reproducing characteristics. We have already proposed an optical recording medium that can be used as an optical recording medium.
本発明はこれをさらに改善したもので、量産性
および耐候性に優れ、かつ高感度で信号品質が良
好であると共に、充分に大きなレーザパワーで長
時間再生しうる光記録媒体を提供することを目的
とする。 The present invention is a further improvement on this, and aims to provide an optical recording medium that is excellent in mass production and weather resistance, has high sensitivity and good signal quality, and can be reproduced for a long time with a sufficiently large laser power. purpose.
［問題点を解決するための手段］
本発明は基板と、レーザ光によつて一部が選択
的に除去されて情報を記録する前記基板上に形成
された記録層とからなる光記録媒体において、前
記記録層中に、順次積層されたセレンを主成分と
する層、テルルおよび窒素を主成分とする層およ
びセレンを主成分とする層を少なくとも有してい
ることを特徴とする光記録媒体である。[Means for Solving the Problems] The present invention provides an optical recording medium comprising a substrate and a recording layer formed on the substrate, a portion of which is selectively removed by laser light to record information. , an optical recording medium characterized in that the recording layer has at least a layer mainly composed of selenium, a layer mainly composed of tellurium and nitrogen, and a layer mainly composed of selenium, which are laminated in sequence. It is.
本発明において例えば第１図に示すように基板
１上にセレンを主成分とする層（以下セレン層と
略す）２、テルルおよび窒素を主成分とする層
（以下テルル−窒素層と略す）３、およびセレン
層４が順次積層されて記録層を形成する。このほ
か、基板１とセレン層２の間および／またはセレ
ン層４の外方に他の層が存在するものであつても
よい。セレン層２、テルル−窒素層３およびセレ
ン層４の３層を少なくとも順次設けることにより
大きなレーザパワーで長時間再生しても再生特性
が劣化せず、優れた光記録媒体が得られる。 In the present invention, for example, as shown in FIG. 1, a layer containing selenium as a main component (hereinafter referred to as a selenium layer) 2 and a layer containing tellurium and nitrogen as main components (hereinafter referred to as a tellurium-nitrogen layer) 3 are provided on a substrate 1. , and selenium layer 4 are sequentially laminated to form a recording layer. In addition, other layers may be present between the substrate 1 and the selenium layer 2 and/or outside the selenium layer 4. By providing at least the three layers of selenium layer 2, tellurium-nitrogen layer 3, and selenium layer 4 in sequence, the reproduction characteristics do not deteriorate even if reproduction is performed for a long time with high laser power, and an excellent optical recording medium can be obtained.
上下のセレン層の膜厚はそれぞれ５Å〜100Å
の範囲、テルル−窒素層の膜厚は100Å〜1000Å
の範囲が記録再生特性、耐候性の観点から望まし
い。テルル−窒素層における窒素の含有量は原子
数パーセントで２パーセント以上20パーセント未
満が記録再生特性、耐候性の観点から望ましい。 The thickness of the upper and lower selenium layers is 5 Å to 100 Å, respectively.
range, tellurium-nitrogen layer thickness is 100Å to 1000Å
The range is desirable from the viewpoint of recording/reproducing characteristics and weather resistance. The nitrogen content in the tellurium-nitrogen layer is desirably 2% or more and less than 20% in terms of atomic percent from the viewpoint of recording/reproducing characteristics and weather resistance.
基板としてはポリカーボネート、ポリオレフイ
ン、ポリメチルペンテン、アクリル、エポキシ樹
脂等の合成樹脂やガラスなど通常使用されている
ものが用いられる。 As the substrate, commonly used materials such as synthetic resins such as polycarbonate, polyolefin, polymethylpentene, acrylic and epoxy resins, and glass are used.
［実施例］ 以下本発明の実施例について説明する。[Example] Examples of the present invention will be described below.
実施例
100℃で２時間アニール処理した内径15mm、外
径130mm、厚さ1.2mmのポリカーボネート樹脂デイ
スク基板を真空装置内に入れ、３×10-6TOrr以
下に排気した。蒸発源として、第１の抵抗加熱用
ボードにテルル（Te）を入れ、第２の抵抗加熱
用ボートにセレン（Se）を入れた。窒素ガス雰
囲気での反応性蒸着により、Seを主成分とする
層を40Å厚、Teと窒素（Ｎ）の層を260Å厚（Ｎ
の含有量は原子数パーセントで６パーセント）、
Seを主成分とする層を40Å厚順次積層した。こ
の光デイスクを95℃の窒素雰囲気中で１時間アニ
ールしたのち、波長8300Åにおける基板入射率を
測定したところ38％であつた。波長8300Åの半導
体レーザ光を基板を通して入射して記録層上で
1.6μmφ程度に絞り、媒体線速度5.6m／sec、記録
周波数3.77MHz、記録パルス幅70nsuc、記録パ
ワー5.5mwの条件で記録し、0.7mwで再生した。
バンド幅30KHzのキヤリアーとノイズの比
（Ｃ／Ｎ）は50dBと良好であり、1.0mwで106回
再生しても同様に良好であつた。Example A polycarbonate resin disk substrate having an inner diameter of 15 mm, an outer diameter of 130 mm, and a thickness of 1.2 mm, which had been annealed at 100° C. for 2 hours, was placed in a vacuum device and evacuated to 3×10 −6 TOrr or less. As evaporation sources, tellurium (Te) was placed in the first resistance heating board, and selenium (Se) was placed in the second resistance heating boat. By reactive evaporation in a nitrogen gas atmosphere, a layer mainly composed of Se was formed to a thickness of 40 Å, and a layer of Te and nitrogen (N) was formed to a thickness of 260 Å (N
The content is 6% in atomic percent),
Layers containing Se as the main component were sequentially stacked to a thickness of 40 Å. After this optical disk was annealed for 1 hour in a nitrogen atmosphere at 95° C., the incidence rate on the substrate at a wavelength of 8300 Å was measured and found to be 38%. Semiconductor laser light with a wavelength of 8300 Å is incident on the recording layer through the substrate.
Recording was performed under conditions of a medium linear velocity of 5.6 m/sec, a recording frequency of 3.77 MHz, a recording pulse width of 70 nsuc, and a recording power of 5.5 mw, and reproduction was performed at 0.7 mw.
The carrier-to-noise ratio (C/N) with a bandwidth of 30 KHz was good at 50 dB, and it remained good even after 106 times of playback at 1.0 mw.
次に、本実施例のデイスクを70℃、80％の高温
高湿度の環境に60時間保存した後、上記特性を調
べたが変化はなく、耐候性に優れた光記録媒体で
あることが確認された。 Next, after storing the disk of this example in a high temperature and high humidity environment of 70°C and 80% for 60 hours, the above characteristics were examined, and there was no change, confirming that it is an optical recording medium with excellent weather resistance. It was done.
比較のために通常の蒸着で40Å厚のSe、260Å
厚のTe、40Å厚のSeを順次積層したデイスクで
は、1.0mwで106回再生するとＣ／Ｎが約1dB劣
化した。 For comparison, 40 Å thick Se with normal deposition, 260 Å
In a disk in which a thick Te layer and a 40 Å thick Se layer were sequentially laminated, the C/N deteriorated by about 1 dB when played back 10 6 times at 1.0 mw.
［発明の効果］
以上説明したように本発明の光記録媒体は量産
性および耐候性に優れていると共に、高感度で信
号品質が良好であり、かつ充分に大きなレーザパ
ワーで長時間再生しうるものである。[Effects of the Invention] As explained above, the optical recording medium of the present invention is excellent in mass production and weather resistance, has high sensitivity and good signal quality, and can be reproduced for a long time with a sufficiently large laser power. It is something.
第１図は本発明の光記録媒体の１実施例を示す
部分断面図、第２図は従来の光記録媒体を示す部
分断面図である。
１……基板、２，４……セレン層、３……テル
ル−窒素層、２１……記録層、２２……ピツト。
FIG. 1 is a partial sectional view showing one embodiment of the optical recording medium of the present invention, and FIG. 2 is a partial sectional view showing a conventional optical recording medium. DESCRIPTION OF SYMBOLS 1... Substrate, 2, 4... Selenium layer, 3... Tellurium-nitrogen layer, 21... Recording layer, 22... Pit.
Claims (1)
去されて情報を記録する前記基板上に形成された
記録層とからなる光記録媒体において、前記記録
層中に、順次積層されたセレンを主成分とする
層、テルルおよび窒素を主成分とする層およびセ
レンを主成分とする層を少なくとも有しているこ
とを特徴とする光記録媒体。1. In an optical recording medium consisting of a substrate and a recording layer formed on the substrate, a portion of which is selectively removed by a laser beam to record information, the recording layer includes selenium layered sequentially. 1. An optical recording medium comprising at least a layer containing tellurium as a main component, a layer containing tellurium and nitrogen as a main component, and a layer containing selenium as a main component.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61143383A JPS62299394A (en) | 1986-06-18 | 1986-06-18 | Optical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61143383A JPS62299394A (en) | 1986-06-18 | 1986-06-18 | Optical recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62299394A JPS62299394A (en) | 1987-12-26 |
| JPH0481951B2 true JPH0481951B2 (en) | 1992-12-25 |
Family
ID=15337494
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61143383A Granted JPS62299394A (en) | 1986-06-18 | 1986-06-18 | Optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62299394A (en) |
-
1986
- 1986-06-18 JP JP61143383A patent/JPS62299394A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62299394A (en) | 1987-12-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |