JPH07296449A - Information storage medium - Google Patents
Information storage mediumInfo
- Publication number
- JPH07296449A JPH07296449A JP11216994A JP11216994A JPH07296449A JP H07296449 A JPH07296449 A JP H07296449A JP 11216994 A JP11216994 A JP 11216994A JP 11216994 A JP11216994 A JP 11216994A JP H07296449 A JPH07296449 A JP H07296449A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- information storage
- storage medium
- magnetic layer
- magnetic
- 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
Links
- 239000010410 layer Substances 0.000 claims abstract description 88
- 230000003287 optical effect Effects 0.000 claims abstract description 17
- 239000011241 protective layer Substances 0.000 claims abstract description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 8
- 229910052799 carbon Inorganic materials 0.000 claims description 8
- 229910052797 bismuth Inorganic materials 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 230000002040 relaxant effect Effects 0.000 claims description 3
- 229910052709 silver Inorganic materials 0.000 claims description 3
- 229910000531 Co alloy Inorganic materials 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 239000000758 substrate Substances 0.000 abstract description 17
- 238000004544 sputter deposition Methods 0.000 abstract description 9
- 230000001050 lubricating effect Effects 0.000 abstract description 4
- 229920005989 resin Polymers 0.000 abstract description 3
- 239000011347 resin Substances 0.000 abstract description 3
- 229920005668 polycarbonate resin Polymers 0.000 abstract description 2
- 239000004431 polycarbonate resin Substances 0.000 abstract description 2
- 238000003848 UV Light-Curing Methods 0.000 abstract 1
- 238000002347 injection Methods 0.000 abstract 1
- 239000007924 injection Substances 0.000 abstract 1
- 239000002344 surface layer Substances 0.000 abstract 1
- 229910002441 CoNi Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、光ディスクや磁気デイ
スク等の情報記憶媒体に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information storage medium such as an optical disk and a magnetic disk.
【０００２】[0002]
【従来の技術】従来、透明な樹脂基板を用いた光ディス
クに、書換え可能な磁気記憶層を設けた記憶ディスクの
提案がなされている（特開昭5-54461 号他参照）。この
ような記憶ディスクによれば、記憶容量が増すと共に、
随時書き込み及び読み出しが可能な便利な媒体である。2. Description of the Related Art Conventionally, there has been proposed a storage disk in which a rewritable magnetic storage layer is provided on an optical disk using a transparent resin substrate (see Japanese Patent Laid-Open No. 5-54461). With such a storage disk, the storage capacity increases and
It is a convenient medium that can be written and read at any time.
【０００３】[0003]
【発明が解決しようとする課題】ところで、このような
記憶ディスクにおいて、磁気記憶層から大きな再生出力
を得ようとする場合には、磁性層をある程度厚くする必
要がある。ところが、上述したものは、従来の光学用コ
ンパクト・デイスクに相当する箇所を基板部として、こ
の上にスパッタリングにより下地膜を形成し、更にその
上にある程度の厚さの磁性層を形成しており、それらの
磁性層表面を観察すると、クラックが多数発生してい
る。特に、磁性膜を厚くしたものにその傾向が顕著に表
れている。こうしたクラックは、その長さが数μｍ〜数
十μｍのもので、電磁変換特性上のノイズ発生源とな
り、Ｓ／Ｎを大きく劣化してしまう懸念のあるものであ
る。そこで、本発明は、上述のような光記憶層と磁気記
録層とを併せもつ情報記憶媒体において、再生出力を上
げるために磁気記録層を所定の厚みとする場合にも、磁
性層にクラックを生じさせないようにすることにある。By the way, in such a storage disk, in order to obtain a large reproduction output from the magnetic storage layer, it is necessary to make the magnetic layer thick to some extent. However, in the above-mentioned one, a portion corresponding to a conventional optical compact disc is used as a substrate portion, a base film is formed on the substrate portion by sputtering, and a magnetic layer having a certain thickness is further formed thereon. When observing the surfaces of those magnetic layers, many cracks were generated. In particular, the tendency is remarkably exhibited in the thick magnetic film. These cracks have a length of several μm to several tens of μm, and are a source of noise generation in electromagnetic conversion characteristics, and there is a concern that S / N may be significantly deteriorated. Therefore, in the present invention, in the information storage medium having both the optical storage layer and the magnetic recording layer as described above, even when the magnetic recording layer has a predetermined thickness in order to increase the reproduction output, the magnetic layer is cracked. To prevent it from happening.
【０００４】[0004]
【課題を解決するための手段】本発明の情報記憶媒体
は、上述の問題点を解決するために、以下の１）〜４）
に記載の手段を提供しようというものである。即ち、 １）少なくとも、光情報記憶層と、この上面に形成され
る保護層と、この上面側に形成される磁性層とが設けら
れる情報記憶媒体において、前記保護層と前記磁性層と
の間に、前記磁性層への応力を緩和するための応力緩和
層を設けたことを特徴とする情報記憶媒体。In order to solve the above problems, the information storage medium of the present invention has the following 1) to 4).
It is intended to provide the means described in. That is, 1) In an information storage medium provided with at least an optical information storage layer, a protective layer formed on the upper surface, and a magnetic layer formed on the upper surface side, between the protective layer and the magnetic layer. An information storage medium, further comprising a stress relaxation layer for relaxing stress on the magnetic layer.
【０００５】２）請求項１記載の情報記憶媒体におい
て、応力緩和層をカ−ボン、Ａｇ、Ｃｕ、Ｂｉ、Ｚｎ、
又はＮｉＰ等の非磁性アモルファス材で形成したことを
特徴とする情報記憶媒体。2) In the information storage medium according to claim 1, the stress relaxation layer is made of carbon, Ag, Cu, Bi, Zn,
Alternatively, the information storage medium is formed of a non-magnetic amorphous material such as NiP.
【０００６】３）請求項１記載の情報記憶媒体におい
て、磁性層の下層に下地層を設け、この下地層をＣｒ、
又は、これに近い面間隔を有する体心立方構造の組成物
で形成したことを特徴とする情報記憶媒体。3) In the information storage medium according to claim 1, an underlayer is provided below the magnetic layer, and the underlayer is made of Cr,
Alternatively, an information storage medium formed of a composition having a body-centered cubic structure having a surface spacing close to this.
【０００７】４）請求項１記載の情報記憶媒体におい
て、磁性層をＣｏ合金で形成したことを特徴とする情報
記憶媒体。4) The information storage medium according to claim 1, wherein the magnetic layer is formed of a Co alloy.
【０００８】[0008]
【実施例】以下、本発明の情報記憶媒体の実施例につき
説明する。図１は、その一実施例であるデイスク状の情
報記憶媒体の概略断面図である。１は直径１２０ｍｍの
透明なポリカーボネート樹脂製の基板で、この上部側に
はスタンパにより射出成形された凹凸部１ａが設けられ
ている。この凹凸部１ａ上には、スパッタリング法によ
り１000 オングストロ−ムの厚さのＡｌ膜により光記録
層２が設けられ、前記基板１を通じて供給される照射光
を反射して信号伝達を行う構成になっている。更に、こ
の光記録層２の上面に、紫外線硬化樹脂がスピンドルコ
ート法により塗布されて光保護層３が設けられている。
以上の各層が、これより上層に設けられる各層の基板部
Ａとなっている。EXAMPLES Examples of the information storage medium of the present invention will be described below. FIG. 1 is a schematic cross-sectional view of a disk-shaped information storage medium which is one example thereof. Reference numeral 1 denotes a transparent polycarbonate resin substrate having a diameter of 120 mm, and an uneven portion 1a injection-molded by a stamper is provided on the upper side of the substrate. An optical recording layer 2 made of an Al film having a thickness of 1000 angstrom is provided on the uneven portion 1a by a sputtering method, and the irradiation light supplied through the substrate 1 is reflected to transmit a signal. ing. Further, an ultraviolet curable resin is applied on the upper surface of the optical recording layer 2 by a spindle coating method to provide an optical protective layer 3.
Each of the above layers is the substrate portion A of each layer provided above it.
【０００９】そして、この基板部Ａ、すなわち、光保護
層３の上面には、下層側と上層側との応力を緩和するた
めのカ−ボンより成る応力緩和層４と、Ｃｒより成る下
地層５と、ＣｏＮｉＣｒより成る磁性層６と、更に、こ
の磁性層６を保護するための保護層７と、潤滑層８とが
順次積層された構成となっている。Then, on the substrate portion A, that is, on the upper surface of the light protection layer 3, a stress relaxation layer 4 made of carbon for relaxing stress on the lower layer side and an upper layer side, and an underlayer made of Cr. 5, a magnetic layer 6 made of CoNiCr, a protective layer 7 for protecting the magnetic layer 6, and a lubricating layer 8 are sequentially laminated.
【００１０】次に、基板部Ａ上に設けられる応力緩和層
４、下地層５及び磁性層６の形成方法につき説明する。
この形成にあたっては、上述の基板部Ａが形成されたと
ころで、この基板部Ａを６インチのタ−ゲットを有する
ＤＣマグネトロンスパッタ装置に取り付け、到着真空度
４×１０-7Ｔｏｒｒ．まで排気を行う。この時、基板部
Ａは加熱しない。スパッタ時の基板部Ａの温度はおよそ
２０℃とする。そして、基板部Ａ上にカ−ボンを400 オ
ングスト−ムの厚さで、その上にＣｒを500 オングスト
−ムの厚さで、更に、その上面にＣｏＮｉ18Ｃｒ9 を20
00 オングストロ−ムの厚さで順次以下の条件で成膜し
たものである。Next, a method of forming the stress relaxation layer 4, the underlayer 5 and the magnetic layer 6 provided on the substrate portion A will be described.
In this formation, when the above-mentioned substrate portion A was formed, this substrate portion A was attached to a DC magnetron sputtering device having a 6-inch target, and the arrival vacuum degree was 4 × 10 −7 Torr. Exhaust until. At this time, the substrate part A is not heated. The temperature of the substrate portion A at the time of sputtering is about 20 ° C. Then, carbon is formed on the substrate portion A with a thickness of 400 angstroms, Cr is formed thereon with a thickness of 500 angstroms, and CoNi 18 Cr 9 is formed on the upper surface thereof with a thickness of 20 Å.
The film was sequentially formed under the following conditions with a thickness of 00 angstrom.
【００１１】 ＜スパッタ条件＞ 応力緩和層（カ−ボン） スパッタガス圧：0.8 ｍＴｏｒｒ． スパッタレ−ト：0.83オングスト−ム／ｓｅｃ． 下地層（Ｃｒ） スパッタガス圧：３５ｍＴｏｒｒ． スパッタレ−ト：2.65オングスト−ム／ｓｅｃ． 磁性層（ＣｏＮｉＣｒ） スパッタガス圧：３５ｍＴｏｒｒ． スパッタレ−ト：5.44オングスト−ム／ｓｅｃ．<Sputtering conditions> Stress relaxation layer (carbon) Sputtering gas pressure: 0.8 mTorr. Sputter rate: 0.83 angstrom / sec. Underlayer (Cr) Sputtering gas pressure: 35 mTorr. Sputter rate: 2.65 angstrom / sec. Magnetic layer (CoNiCr) Sputtering gas pressure: 35 mTorr. Sputter rate: 5.44 angstrom / sec.
【００１２】そして、このような条件の基に形成された
磁性層６上に、ＤＣスパッタ法によりカ−ボンより成る
磁性膜保護層７及びフッソ系の潤滑剤により潤滑層８が
順次形成されて上記構成の情報記憶媒体が形成される。On the magnetic layer 6 formed under the above conditions, a magnetic film protective layer 7 made of carbon and a lubricating layer 8 made of a fluorine-based lubricant are sequentially formed by a DC sputtering method. An information storage medium having the above configuration is formed.
【００１３】次に、本実施例による情報記憶媒体と、従
来の情報記憶媒体、即ち、応力緩和層４を設けない情報
記憶媒体との比較を行った。この場合、比較試料とし
は、共に、磁性膜保護層７及び潤滑層８を設けない情報
記憶媒体で行った。図２及び図３は、磁性層の表面を走
査型電子顕微鏡（ＳＥＭ）により観察した時の部分写真
を複写手段により複写した図で示したものである。図２
において、同図（Ａ）は本実施例による情報記憶媒体の
磁性層を示し、同図（Ｂ）は従来の情報記憶媒体の磁性
層を示したもので、それぞれ、5,000 倍の倍率で観察を
行ったものである。同様に、図３において、同図（Ａ）
は本実施例による情報記憶媒体の磁性層を示し、同図
（Ｂ）は従来の情報記憶媒体の磁性層を示したもので、
それぞれ、10,000 倍の倍率で観察を行ったものであ
る。Next, a comparison was made between the information storage medium according to this embodiment and a conventional information storage medium, that is, an information storage medium in which the stress relaxation layer 4 is not provided. In this case, as a comparative sample, an information storage medium without the magnetic film protective layer 7 and the lubricating layer 8 was used. FIGS. 2 and 3 show partial photographs of the surface of the magnetic layer observed by a scanning electron microscope (SEM), which are copied by a copying means. Figure 2
2A shows the magnetic layer of the information storage medium according to the present embodiment, and FIG. 2B shows the magnetic layer of the conventional information storage medium, each of which is observed at a magnification of 5,000 times. I went there. Similarly, in FIG. 3, FIG.
Shows the magnetic layer of the information storage medium according to the present embodiment, and FIG. 6B shows the magnetic layer of the conventional information storage medium.
Each of them was observed at a magnification of 10,000 times.
【００１４】これらの図において、明色で示される箇所
と暗色で示される箇所とがあり、これは、明色で示され
る箇所は突出形状部となっており、暗色で示される部分
は凹状形状部となっている。これらの図から明らかな通
り、図（Ａ）の方が図（Ｂ）に比べて突出形状部の形状
がきめ細かく、突出形状部の盛り上がりが少ないことが
分かる。In these figures, there is a portion shown in light color and a portion shown in dark color. The portion shown in light color is a protruding shape portion, and the portion shown in dark color is a concave shape. It is a division. As is clear from these figures, it can be seen that the shape of the protrusion-shaped portion is finer and the protrusion of the protrusion-shaped portion is smaller in FIG.
【００１５】更に、特に、図３（Ｂ）の明色部、即ち、
突出形状部に注目すれば、その頂上部に、細長いすじが
見受けられる。これは、ひび割れ、クラックが生じてい
るもので、ほとんどの突出形状部に見受けられる。Further, in particular, the light-colored portion of FIG. 3B, that is,
If you pay attention to the protruding shape part, you can see an elongated line at the top. These are cracks and cracks, and can be seen in most of the protruding shape parts.
【００１６】突出形状部は、光保護層、下地層及び磁性
層に所定以上の応力の差が生じると、磁性層表面に歪み
が生じ、その結果、突出形状部が所定以上に盛り上が
り、その頂部にクラックが生じるものと考えられる。図
（Ｂ）は、正に、それを示しているものである。When the difference in stress between the light-protecting layer, the underlayer and the magnetic layer exceeds a predetermined value, the protrusion-shaped portion is distorted on the surface of the magnetic layer. It is thought that cracks occur in the. The figure (B) shows just that.
【００１７】これに対して、図（Ａ）に示す本実施例の
情報記憶媒体は、光保護層から磁性層６に至る間にカ−
ボンから成る応力緩和層４を設けているので、磁性層６
に至る応力差がこの層で吸収され下地層５及び磁性層６
にクラックを発生させないようにしているものと考えら
れる。また、上述の実施例において、磁性層６をＣｏＰ
ｔ10で形成した場合にも、同様の結果が得られている。On the other hand, in the information storage medium of this embodiment shown in FIG. 1A, the cover is provided between the optical protection layer and the magnetic layer 6.
Since the stress relaxation layer 4 made of carbon is provided, the magnetic layer 6
The stress difference up to is absorbed by this layer and the underlayer 5 and the magnetic layer 6
It is thought that the cracks are prevented from occurring. In addition, in the above-described embodiment, the magnetic layer 6 is made of CoP.
Similar results are obtained when formed at t 10 .
【００１８】以上述べたように、本実施例によれば、特
に、光保護層と磁性層６との間に、応力緩和層４を設け
たので、この応力緩和層４で、下地層５と磁性層６への
応力を緩和して、磁性層６表面にクラックが発生するの
を未然に防止できる。As described above, according to this embodiment, in particular, since the stress relaxation layer 4 is provided between the light protection layer and the magnetic layer 6, the stress relaxation layer 4 serves as the underlayer 5. It is possible to relax the stress on the magnetic layer 6 and prevent cracks from occurring on the surface of the magnetic layer 6.
【００１９】尚、本実施例では、応力緩和層４をカ−ボ
ンより構成したが、これに限らず、Ａｇ、Ｃｕ、Ｂｉ、
Ｚｎ、又はＮｉＰ等の非磁性アモルファス材であっても
同様な効果が得られる。また、本実施例では、下地層５
をＣｒで構成しているが、これに近い面間隔を有するバ
ナジウム等の体心立方構造のものであっても良い。In the present embodiment, the stress relaxation layer 4 is made of carbon, but the present invention is not limited to this. Ag, Cu, Bi,
Similar effects can be obtained even with a non-magnetic amorphous material such as Zn or NiP. Further, in this embodiment, the underlayer 5
Although Cr is made of Cr, a body-centered cubic structure such as vanadium having a surface spacing close to Cr may be used.
【００２０】[0020]
【発明の効果】本発明によれば、光記憶層と磁性層とを
併せもつ情報記憶媒体において、再生出力を上げるため
に、磁性層を所定以上の厚みとする場合にも、磁性層に
クラックが生ぜず、記録再生時のノイズ原因となるもの
を未然に除去できる。According to the present invention, in an information storage medium having both an optical storage layer and a magnetic layer, even if the magnetic layer has a predetermined thickness or more in order to increase the reproduction output, the magnetic layer is cracked. It does not occur, and it is possible to remove in advance the cause of noise during recording and reproduction.
【図１】本発明の実施例に係る情報記憶媒体の概略断面
図を示す。FIG. 1 is a schematic sectional view of an information storage medium according to an embodiment of the present invention.
【図２】本発明の実施例に係る情報記憶媒体と従来の情
報記憶媒体とを比較図して示した拡大部分図である。FIG. 2 is an enlarged partial view showing an information storage medium according to an embodiment of the present invention and a conventional information storage medium in comparison with each other.
【図３】図２における拡大率を、更に大きくして示した
図である。FIG. 3 is a diagram showing the enlargement ratio in FIG. 2 to a larger extent.
１ 基板 ２ 光記録層 ３ 光保護層 ４ 応力緩和層 ５ 下地層 ６ 磁性層 ７ 保護層 ８ 潤滑層 Ａ 基板部 1 Substrate 2 Optical Recording Layer 3 Optical Protection Layer 4 Stress Relaxation Layer 5 Underlayer 6 Magnetic Layer 7 Protective Layer 8 Lubrication Layer A Substrate Part
Claims (4)
形成される保護層と、この上面側に形成される磁性層と
が設けられる情報記憶媒体において、 前記保護層と前記磁性層との間に、前記磁性層への応力
を緩和するための応力緩和層を設けたことを特徴とする
情報記憶媒体。1. An information storage medium provided with at least an optical information storage layer, a protective layer formed on the upper surface of the optical information storage layer, and a magnetic layer formed on the upper surface side, wherein the protective layer and the magnetic layer are provided. An information storage medium, wherein a stress relaxation layer for relaxing stress on the magnetic layer is provided therebetween.
力緩和層をカ−ボン、Ａｇ、Ｃｕ、Ｂｉ、Ｚｎ、又はＮ
ｉＰ等の非磁性アモルファス材で形成したことを特徴と
する情報記憶媒体。2. The information storage medium according to claim 1, wherein the stress relaxation layer is carbon, Ag, Cu, Bi, Zn, or N.
An information storage medium formed of a non-magnetic amorphous material such as iP.
性層の下層に下地層を設け、この下地層をＣｒ、又は、
これに近い面間隔を有する体心立方構造の組成物で形成
したことを特徴とする情報記憶媒体。3. The information storage medium according to claim 1, wherein an underlayer is provided below the magnetic layer, and the underlayer is Cr or
An information storage medium formed of a composition having a body-centered cubic structure having a surface spacing close to this.
性層をＣｏ合金で形成したことを特徴とする情報記憶媒
体。4. The information storage medium according to claim 1, wherein the magnetic layer is formed of a Co alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11216994A JPH07296449A (en) | 1994-04-27 | 1994-04-27 | Information storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11216994A JPH07296449A (en) | 1994-04-27 | 1994-04-27 | Information storage medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07296449A true JPH07296449A (en) | 1995-11-10 |
Family
ID=14579981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11216994A Pending JPH07296449A (en) | 1994-04-27 | 1994-04-27 | Information storage medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07296449A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004280868A (en) * | 2003-03-12 | 2004-10-07 | Toshiba Corp | optical disk |
-
1994
- 1994-04-27 JP JP11216994A patent/JPH07296449A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004280868A (en) * | 2003-03-12 | 2004-10-07 | Toshiba Corp | optical disk |
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