JP2001184725A - Optical information recording medium - Google Patents
Optical information recording mediumInfo
- Publication number
- JP2001184725A JP2001184725A JP36245999A JP36245999A JP2001184725A JP 2001184725 A JP2001184725 A JP 2001184725A JP 36245999 A JP36245999 A JP 36245999A JP 36245999 A JP36245999 A JP 36245999A JP 2001184725 A JP2001184725 A JP 2001184725A
- Authority
- JP
- Japan
- Prior art keywords
- recording
- layer
- substrate
- thickness
- dielectric layer
- 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
Landscapes
- Optical Record Carriers And Manufacture Thereof (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、基板の凹凸部側に
情報記録層を有し、その上に光透過層が形成されてお
り、上記光透過層側からのレーザ光を照射により原子の
配列が変化して情報の記録および消去が行なわれる光学
的情報記録媒体であって、特に高密度記録および書き換
え特性に優れた光学的情報記録媒体（以下、光ディスク
と呼ぶ）に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording layer on an uneven portion side of a substrate, on which a light transmitting layer is formed. The present invention relates to an optical information recording medium in which information is recorded and erased by changing the arrangement, and particularly to an optical information recording medium (hereinafter, referred to as an optical disk) having excellent high-density recording and rewriting characteristics.
【０００２】[0002]
【従来の技術】近年、光学データ記録方式に関する研究
が各所で進められている。これは、磁気記録方式に比べ
て一桁以上も高い記録密度が達成できること、再生専用
型、追記型、書換可能型のそれぞれのメモリー形態に対
応できる等の数々の利点を有し、産業用から民生用まで
幅広い用途が考えられるからである。最近、書換可能型
のＤＶＤが市場に出たが、未だ記録容量は十分と言えず
テープを記録媒体とするＶＴＲと比較した場合、標準的
な記録モードで1〜1．5時間分しか記録できない。さら
に今後、放送方式のデジタル化を迎え、より高精細な映
像ソースを記録する場合においては一層の高容量、高密
度化が書換型光ディスクに求められる。2. Description of the Related Art In recent years, research on optical data recording systems has been advanced in various places. This has a number of advantages, such as the ability to achieve recording densities that are at least an order of magnitude higher than magnetic recording systems, and the ability to support read-only, write-once, and rewritable memory types. This is because a wide range of applications, including consumer use, is conceivable. Recently, a rewritable DVD has been put on the market, but the recording capacity is still not enough, and only 1 to 1.5 hours can be recorded in a standard recording mode when compared with a VTR using a tape as a recording medium. . In the future, with the digitalization of the broadcasting system, when recording higher definition video sources, even higher capacity and higher density are required for rewritable optical disks.
【０００３】[0003]
【発明が解決しようとする課題】ところで、この高密度
化の要望に応え、レンズの高ＮＡ（開口数）化が進み媒
体とレンズの焦点距離が小さくなる傾向にある。これに
伴い、従来基板側からレーザー光による信号の読み出し
を行っていたが、焦点距離が小さくなるためレンズ基板
間距離が接近し、基板側からの読み出しが困難となる。
この回避策として凹凸面（信号面、記録膜面）側から透
明層を介し、直接読み出す方法が採用されている。By the way, in response to the demand for higher density, the lens has a higher NA (numerical aperture) and the focal length between the medium and the lens tends to be shorter. Along with this, signal reading by laser light has been conventionally performed from the substrate side. However, since the focal length is small, the distance between the lens substrates is short, and reading from the substrate side becomes difficult.
As a workaround, a method of directly reading data from the uneven surface (signal surface, recording film surface) side via a transparent layer is adopted.
【０００４】記録再生型媒体では通常多層膜構成をとる
が、この場合基板に対する膜構成が逆となる。相変化記
録媒体においては反射膜が第一成膜層として基板上に堆
積する。反射層としてよく使用されるＡｌおよびＡｌ系
合金膜は堆積していくと、結晶粒界が成長する性質を有
する。基板側からの読み出す膜構成において反射層は保
護膜を除く最表層となり、ＡｌおよびＡｌ系合金膜が反
射層として使用されてもレーザー光反射面は成膜初期段
階で、粒界成長の影響は無かった。しかしながら、記録
膜面から読み出す構成ではＡｌおよびＡｌ系合金反射層
が凹凸溝面に対し第一層となり、粒界成長した膜上に誘
電体層、記録層が順次堆積される。この結果、粒界によ
る面粗れが誘電体層、記録層へ大きく影響し記録再生特
性、書き換え性能を劣化させる原因となった。（特開平
９−６３１２０号公報）A recording / reproducing medium usually has a multilayer structure, but in this case, the film structure for the substrate is reversed. In a phase change recording medium, a reflective film is deposited on a substrate as a first film formation layer. Al and Al-based alloy films, which are often used as a reflection layer, have the property that crystal grain boundaries grow as they are deposited. In the film configuration read out from the substrate side, the reflective layer is the outermost layer except for the protective film, and even if Al and an Al-based alloy film are used as the reflective layer, the laser light reflective surface is in the initial stage of film formation, and the influence of grain boundary growth is small. There was no. However, in the configuration in which reading is performed from the recording film surface, the Al and Al-based alloy reflection layer becomes the first layer with respect to the uneven groove surface, and the dielectric layer and the recording layer are sequentially deposited on the film grown at the grain boundary. As a result, the surface roughness caused by the grain boundaries greatly affects the dielectric layer and the recording layer, and causes the recording / reproducing characteristics and the rewriting performance to deteriorate. (JP-A-9-63120)
【０００５】[0005]
【課題を解決するための手段】本発明は上述の課題を解
決するため、凹凸部が形成されている基板１上に、反射
層２、少なくとも一層の誘電体層３、相変化型記録層
４、少なくとも一層の誘電体層５、光透過層６を順次積
層してなり、光の照射により前記記録層４を構成する原
子の配列が変化して情報の記録及び消去が行われる光学
的情報記録媒体１０であって、前記反射層２はＡｇを主
成分とし、Ａｇ１-ａＭａとしたとき（ＭはＡｌ、Ａ
ｕ，Ｃｕ，Ｃｏ，Ｎｉ，Ｔｉ，Ｖ，Ｍｏ，Ｍｎ，Ｐｔ，
Ｓｉ，Ｎｂ，Ｆｅ，Ｔａ，Ｈｆ，Ｇａ，Ｐｄ，Ｂｉ，Ｉ
ｎ，Ｗ，Ｚｒから選ばれた少なくとも一つの元素）、そ
の組成が０．００５≦ａ≦０．０５（ａ：Ｍの原子比の
合計）を満たし、厚さが５０ｎｍ以上、１００ｎｍ以下
である光学的情報記録媒体１０を提供することにより解
決したものである。According to the present invention, a reflective layer 2, at least one dielectric layer 3, and a phase change type recording layer 4 are provided on a substrate 1 having an uneven portion. An optical information recording system in which at least one dielectric layer 5 and a light transmitting layer 6 are sequentially laminated, and the arrangement of atoms constituting the recording layer 4 is changed by irradiation of light to record and erase information. In the medium 10, when the reflective layer 2 is mainly composed of Ag and made of Ag1-aMa (M is Al, A
u, Cu, Co, Ni, Ti, V, Mo, Mn, Pt,
Si, Nb, Fe, Ta, Hf, Ga, Pd, Bi, I
at least one element selected from n, W, and Zr), the composition satisfies 0.005 ≦ a ≦ 0.05 (total of the atomic ratios of a: M), and the thickness is 50 nm or more and 100 nm or less. This has been solved by providing the optical information recording medium 10.
【０００６】[0006]
【発明の実施の態様】以下、本発明になる光ディスクを
詳細に説明する。本発明の記録材料は、結晶状態と非晶
状態の少なくとも２つの状態をとり得るＡｇ、Ｉｎ、Ｓ
ｂ、Ｔｅからなる相変化型光記録材料あるいはＧｅ、Ｓ
ｂ、Ｔｅからなる相変化型光記録材料である。消去状態
である結晶状態において、Ａｇ、Ｉｎ、Ｓｂ、Ｔｅのう
ちの単体の結晶相あるいは２元素以上の組み合わせで構
成される結晶相を形成するものである。結晶状態が単一
相であるとは限らず、２相以上の結晶相が混在していて
もよい。記録状態である非晶質状態において、Ｘ線回折
パターンは示さないが局所的には短距離秩序を有してい
てもよく、規則的な電子線回折パターンを示す場合もあ
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical disk according to the present invention will be described in detail. The recording material of the present invention can be made of Ag, In, S which can take at least two states of a crystalline state and an amorphous state.
b, Te phase-change optical recording material or Ge, S
This is a phase change type optical recording material composed of b and Te. In the crystal state that is the erased state, a single crystal phase of Ag, In, Sb, and Te or a crystal phase composed of a combination of two or more elements is formed. The crystal state is not limited to a single phase, and two or more crystal phases may coexist. In the amorphous state, which is a recording state, an X-ray diffraction pattern is not shown, but a short-range order may be locally present, and a regular electron beam diffraction pattern may be shown.
【０００７】また、本発明の記録層は、記録、消去、あ
るいは、オーバーライトによる書換を繰り返しても、従
来の記録層に比べ優れた繰返耐久性と高密度記録が得ら
れる。さらに、従来の記録層に比べ高い変調度が得られ
るため、高密度記録再生時のジッタが抑制され高性能で
ある。In addition, the recording layer of the present invention can provide excellent repetition durability and high-density recording as compared with a conventional recording layer even when recording, erasing, or rewriting by overwriting is repeated. Further, since a higher degree of modulation can be obtained as compared with the conventional recording layer, jitter during high-density recording / reproduction is suppressed and high performance is achieved.
【０００８】本発明の光ディスク１０の代表的な層構成
は、以下に、図１により詳細に説明するように、透明基
板１／反射層２／第１誘電体層３／記録層４／第２誘電
体層５/透明層（光透過層）６の積層体からなる（ここ
で、レーザ光は透明層６側から入射する）。但し本発明
の光ディスク１０の構成はこれに限定されるものではな
い。A typical layer structure of the optical disk 10 of the present invention is, as described in more detail below with reference to FIG. 1, a transparent substrate 1 / reflective layer 2 / first dielectric layer 3 / recording layer 4 / second layer. It is composed of a laminate of a dielectric layer 5 and a transparent layer (light transmitting layer) 6 (here, a laser beam enters from the transparent layer 6 side). However, the configuration of the optical disk 10 of the present invention is not limited to this.
【０００９】図１は、本発明になる光ディスク１０の一
実施例の断面構造を説明するための図である。本発明に
なる光ディスク１０は、基板１上に、反射層２、第１誘
電体層３、記録層４、第２誘電体層５、透明層６が順次
積層されてなるものである。FIG. 1 is a view for explaining a sectional structure of an embodiment of an optical disk 10 according to the present invention. The optical disc 10 according to the present invention is obtained by sequentially laminating a reflective layer 2, a first dielectric layer 3, a recording layer 4, a second dielectric layer 5, and a transparent layer 6 on a substrate 1.
【００１０】本発明の誘電体層（第１，第２誘電体層）
３，５は、記録時に基板１、記録層４などが熱によって
変形し記録特性が劣化することを防止するなど、基板
１、記録層４を熱から保護する効果、光学的な干渉効果
により、再生時の信号コントラストを改善する効果があ
る。さらに、記録層４の結晶化を促進して、消去率を向
上する効果もある。この誘電体層３，５としては、Ｚｎ
Ｓ，ＳｉＯ2、Ｓｉ3Ｎ4、Ａｌ2Ｏ3などの無機薄膜があ
る。特にＳｉ，Ｇｅ，Ａｌ，Ｔｉ，Ｚｒ，Ｔａなどの金
属あるいは半導体の酸化物の薄膜、Ｓｉ、Ｇｅ，Ａｌな
どの金属あるいは半導体の窒化物の薄膜、Ｔｉ、Ｚｒ、
Ｈｆ、Ｓｉなどの金属あるいは半導体の炭化物の薄膜、
ＺｎＳ、Ｉｎ2Ｓ3、ＴａＳ4、ＧｅＳ2等の金属あるいは
半導体の硫化物の薄膜、及びこれらの化合物の２種類以
上の混合物の膜が、耐熱性が高く、化学的に安定なこと
から好ましい。The dielectric layer of the present invention (first and second dielectric layers)
The effects of protecting the substrate 1 and the recording layer 4 from heat, such as preventing the substrate 1 and the recording layer 4 from being deformed by heat and deteriorating the recording characteristics during recording, and the optical interference effect, This has the effect of improving the signal contrast during reproduction. Further, there is an effect that the crystallization of the recording layer 4 is promoted and the erasing rate is improved. As the dielectric layers 3 and 5, Zn
There are inorganic thin films such as S, SiO 2 , Si 3 N 4 and Al 2 O 3 . In particular, a thin film of a metal or semiconductor oxide such as Si, Ge, Al, Ti, Zr, or Ta; a thin film of a metal or semiconductor nitride such as Si, Ge, or Al;
Thin films of metals such as Hf and Si or carbides of semiconductors,
Thin films of sulfides of metals or semiconductors such as ZnS, In 2 S 3 , TaS 4 , and GeS 2 , and films of a mixture of two or more of these compounds are preferable because of high heat resistance and chemical stability. .
【００１１】前記光学的な干渉効果を利用し、反射率、
再生時の信号コントラスト等をより一層改善するため
に、精密な光学計算結果を基に誘電体層（第１，第２誘
電体層）３，５を２層以上積層することが好ましい。ま
た、溶融、冷却を繰返す記録層４と界面を接する誘電体
層３，５の元素成分が、記録層４中へ拡散することを抑
制するために、両界面または片面に１層の誘電体層を加
えることが好ましい。前記拡散を抑制することによっ
て、繰返し書換え特性の向上を図ることが可能である。
また、結晶とアモルファスのコントラストを逆転するた
めに、吸収率を制御する目的で、吸収のある誘電体層を
加えることが好ましい。コントラストの逆転は、高転送
レート化に対し効果がある。上記の理由から、誘電体層
は、少なくとも１層以上とすることが好ましい。Using the optical interference effect, the reflectance,
In order to further improve the signal contrast and the like at the time of reproduction, it is preferable to laminate two or more dielectric layers (first and second dielectric layers) 3 and 5 based on a precise optical calculation result. Also, in order to prevent the element components of the dielectric layers 3 and 5 that contact the interface with the recording layer 4 that repeats melting and cooling from diffusing into the recording layer 4, one dielectric layer is provided on both interfaces or on one surface. Is preferably added. By suppressing the diffusion, it is possible to improve the rewrite characteristics repeatedly.
In order to reverse the contrast between the crystal and the amorphous, it is preferable to add an absorbing dielectric layer for the purpose of controlling the absorptance. Reversing the contrast is effective for increasing the transfer rate. For the above reason, it is preferable that the dielectric layer be at least one layer or more.
【００１２】さらに、記録層４への誘電体層を構成する
原子の拡散がないものが好ましい。これらの酸化物、硫
化物、窒化物、炭化物は必ずしも化学量論的組成をとる
必要はなく、屈折率等の制御のために組成を制御した
り、混合して用いることも有効である。Further, it is preferable that there is no diffusion of atoms constituting the dielectric layer into the recording layer 4. These oxides, sulfides, nitrides, and carbides do not always need to have a stoichiometric composition, and it is effective to control the composition for controlling the refractive index and the like, or to use a mixture thereof.
【００１３】また、これらにＭｇＦ2などのフッ化物を
混合したものも、膜の残留応力が小さいことから好まし
い。特にＺｎＳとＳｉＯ2の混合膜は、記録、消去の繰
り返しによっても、記録感度、Ｃ／Ｎ、消去率などの劣
化が起きにくいことから好ましい。A mixture of these and a fluoride such as MgF 2 is also preferable because the residual stress of the film is small. In particular, a mixed film of ZnS and SiO 2 is preferable because deterioration of recording sensitivity, C / N, erasure rate, and the like hardly occurs even when recording and erasing are repeated.
【００１４】前記した第１および第２誘電体層３，５の
厚さは、およそ１０ｎｍ〜５００ｎｍである。第１誘電
体層３は、Ｃ／Ｎ、消去率などの記録特性、安定に多数
回の書換が可能なことから１０ｎｍ〜５０ｎｍが好まし
い。また第２誘電体層５は、透明層６や記録層４から剥
離し難く、クラックなどの欠陥が生じ難いことから、５
０ｎｍ〜３００ｎｍが好ましい。第１誘電体層３と第２
誘電体層５は、同一ではなく異なる化合物から構成され
てもよい。The thickness of the first and second dielectric layers 3, 5 is about 10 nm to 500 nm. The thickness of the first dielectric layer 3 is preferably 10 nm to 50 nm because recording characteristics such as C / N and erasing rate and stable rewriting can be performed many times. In addition, the second dielectric layer 5 is difficult to peel off from the transparent layer 6 and the recording layer 4 and hardly causes defects such as cracks.
0 nm to 300 nm is preferred. The first dielectric layer 3 and the second
The dielectric layers 5 may be made of different compounds instead of the same.
【００１５】本発明の記録層４の厚さとしては、特に限
定するものではないが１０ｎｍ〜１００ｎｍである。理
由としては以下の通りである。記録層４の厚さが１０ｎ
ｍ以下の場合、結晶状態での反射率と非晶質ないし微結
晶状態での反射率との差、すなわ変調度が十分得られ
ず、再生信号強度が大きくとれない。また、記録層４の
厚さが１００ｎｍ以上の場合、この記録層４の熱容量が
大きいためレーザビーム照射時間内で結晶化が完全に行
われない（消し残りあり）、もしくは記録時においては
十分非晶質せず、再結晶化する部分が見られる等記録消
去の劣化を招く。The thickness of the recording layer 4 of the present invention is not particularly limited, but is 10 nm to 100 nm. The reasons are as follows. The thickness of the recording layer 4 is 10 n
If m or less, the difference between the reflectance in the crystalline state and the reflectance in the amorphous or microcrystalline state, that is, a sufficient degree of modulation cannot be obtained, and the reproduction signal intensity cannot be large. When the thickness of the recording layer 4 is 100 nm or more, the crystallization is not completely performed within the laser beam irradiation time due to the large heat capacity of the recording layer 4 (there is no erased portion), or the recording layer 4 is not sufficiently erased. Deterioration of recording and erasure is caused, for example, a portion that is not crystalline and is recrystallized.
【００１６】さらに記録層４の厚さが４０ｎｍ以上の場
合、ダイレクト・オーバーライトを繰り返すと記録マー
ク内で物質移動が起こり、その結果記録層厚に変動が生
じ、オーバーパワーで記録消去が行われるため繰り返し
特性が劣化する。本発明の記録層４の組成においては、
特に記録、消去感度が高く、多数回の記録消去が可能で
あることから１０ｎｍ以上４０ｎｍ以下とすることが好
ましい。Further, when the thickness of the recording layer 4 is 40 nm or more, when direct overwriting is repeated, mass transfer occurs in the recording mark, and as a result, the thickness of the recording layer fluctuates, and recording / erasing is performed with overpower. Therefore, the repetition characteristics deteriorate. In the composition of the recording layer 4 of the present invention,
In particular, the recording and erasing sensitivity is high, and the recording and erasing can be performed many times.
【００１７】本発明の反射層２の材質としては、光反射
性を有するＡｇを主成分とし、Ａｌ，Ａｕ，Ｃｕ，Ｃ
ｏ，Ｎｉ，Ｔｉ，Ｖ，Ｍｏ，Ｍｎ，Ｐｔ，Ｓｉ，Ｎｂ，
Ｆｅ，Ｔａ，Ｈｆ，Ｇａ，Ｐｄ，Ｂｉ，Ｉｎ，Ｗ，Ｚｒ
から選ばれた少なくとも一つの添加元素を含む合金であ
る。Ａｇを主成分とする合金は、光反射性が高く、かつ
熱伝導率を高くできることから好ましい。The material of the reflection layer 2 of the present invention is mainly composed of Ag having light reflectivity, and Al, Au, Cu, C
o, Ni, Ti, V, Mo, Mn, Pt, Si, Nb,
Fe, Ta, Hf, Ga, Pd, Bi, In, W, Zr
An alloy containing at least one additional element selected from the group consisting of: An alloy containing Ag as a main component is preferable because it has high light reflectivity and high thermal conductivity.
【００１８】前述の合金の例として、耐腐食性が良好で
かつ繰り返し性能がのびることから、Ａｇを主成分と
し、Ａｇ１-aＭaとしたとき（ＭはＡｌ、Ａｕ，Ｃｕ，
Ｃｏ，Ｎｉ，Ｔｉ，Ｖ，Ｍｏ，Ｍｎ，Ｐｔ，Ｓｉ，Ｎ
ｂ，Ｆｅ，Ｔａ，Ｈｆ，Ｇａ，Ｐｄ，Ｂｉ，Ｉｎ，Ｗ，
Ｚｒから選ばれた少なくとも一つの元素）、その組成が
０．００５≦a≦０．０５（a：Ｍの原子比の合計）であ
ることが好ましい。０．００５≧ａである場合、Ａｇを
主成分とする合金反射層の耐食性は著しく劣化し、また
ａ≧０．０５の場合、同合金反射層の熱伝導率が低下
し、結果的に記録感度の低下、繰り返し書換性能が劣化
する傾向を示す。As an example of the above-mentioned alloys, Ag is a main component and Ag1-aMa is used (M is Al, Au, Cu,
Co, Ni, Ti, V, Mo, Mn, Pt, Si, N
b, Fe, Ta, Hf, Ga, Pd, Bi, In, W,
It is preferable that at least one element selected from Zr) has a composition of 0.005 ≦ a ≦ 0.05 (total atomic ratio of a: M). When 0.005 ≧ a, the corrosion resistance of the alloy reflective layer containing Ag as a main component is significantly deteriorated, and when a ≧ 0.05, the thermal conductivity of the alloy reflective layer is reduced, resulting in recording. The sensitivity tends to decrease and the rewriting performance tends to deteriorate.
【００１９】反射層２の厚さとしては、おおむね５０ｎ
ｍ以上１００ｎｍ以下である。反射層２の厚さが５０ｎ
ｍ以下の場合、記録層４の熱拡散が不十分で消去特性が
劣化する。また、反射層２の厚さが１００ｎｍ以上の場
合、記録感度が著しく悪くなり記録消去特性が劣化す
る。特に、５０ｎｍ以上１００ｎｍ以下では記録感度が
高く、高速でシングルビーム・オーバーライトが可能で
あり、かつ消去率が大きく消去特性が良好であることか
ら、光ディスク１０の主要部を構成することが好まし
い。The thickness of the reflection layer 2 is approximately 50 n
m or more and 100 nm or less. The thickness of the reflective layer 2 is 50n
If it is less than m, the thermal diffusion of the recording layer 4 is insufficient and the erasing characteristics deteriorate. When the thickness of the reflective layer 2 is 100 nm or more, the recording sensitivity is remarkably deteriorated, and the recording / erasing characteristics are deteriorated. In particular, when the thickness is 50 nm or more and 100 nm or less, it is preferable to constitute a main part of the optical disc 10 because recording sensitivity is high, single-beam overwriting can be performed at high speed, and an erasing rate is large and erasing characteristics are good.
【００２０】本発明の透明層６としては、紫外線によっ
て硬化する樹脂層、もしくはガラス、ポリカーボネイ
ト、ポリメチル・メタクリレート、ポリオレフィン樹
脂、エポキシ樹脂、ポリイミド樹脂などのシートがあげ
られる。シートは接着層を介して記録層と貼り合わせら
れる。透明層の厚さとしては、おおむね１００μｍ以上
２００μｍ以下である。As the transparent layer 6 of the present invention, a resin layer which is cured by ultraviolet rays, or a sheet of glass, polycarbonate, polymethyl methacrylate, polyolefin resin, epoxy resin, polyimide resin or the like can be used. The sheet is bonded to the recording layer via the adhesive layer. The thickness of the transparent layer is generally not less than 100 μm and not more than 200 μm.
【００２１】本発明の基板１の材料としては、透明な各
種の合成樹脂、透明ガラスなどが使用できる。ほこり、
基板の傷などの影響をさけるために、透明基板を用い、
集束した光ビームで基板側から記録を行なうことが好ま
しく、この様な透明基板材料としては、ガラス、ポリカ
ーボネイト、ポリメチル・メタクリレート、ポリオレフ
ィン樹脂、エポキシ樹脂、ポリイミド樹脂などがあげら
れる。特に、光学的複屈折が小さく、吸湿性が小さく、
成形が容易であることからポリカーボネイト樹脂が好ま
しい。さらに記録密度を向上するため、基板上に積層媒
体を設け極薄い板厚の透光性基板を通して、いわゆる表
読みを行ってもよく、この場合にはレーザ光は基板を通
過しないので不透明な基板を用いることが可能となる。As the material of the substrate 1 of the present invention, various transparent synthetic resins, transparent glass and the like can be used. Dust,
To avoid the effects of scratches on the substrate, use a transparent substrate,
Recording is preferably performed from the substrate side with a focused light beam. Examples of such a transparent substrate material include glass, polycarbonate, polymethyl methacrylate, polyolefin resin, epoxy resin, and polyimide resin. In particular, optical birefringence is small, hygroscopicity is small,
Polycarbonate resins are preferred because of ease of molding. In order to further improve the recording density, a so-called table reading may be performed through a very thin translucent substrate by providing a laminated medium on the substrate. In this case, the opaque substrate is used because the laser beam does not pass through the substrate. Can be used.
【００２２】基板１の厚さは特に限定するものではない
が、０．０１ｍｍ〜５ｍｍが実用的である。０．０１ｍ
ｍ未満では、基板１側から集束した光ビームで記録する
場合でも、ごみの影響を受け易くなり、５ｍｍ以上で
は、対物レンズの開口数を大きくすることが困難にな
り、照射光ビームスポットサイズが大きくなるため、記
録密度をあげることが困難になる。基板１はフレキシブ
ルなものであっても良いし、リジッドなものであっても
良い。フレキシブルな基板１は、テープ状、シート状、
カ-ド状で使用する。リジッドな基板１は、カード状、
あるいはディスク状で使用する。また、これらの基板１
は、記録層４などを形成した後、２枚の基板を用いて、
エアーサンドイッチ構造、エアーインシデント構造、密
着貼り合せ構造としてもよい。The thickness of the substrate 1 is not particularly limited, but is practically 0.01 mm to 5 mm. 0.01m
If it is less than m, even when recording with a light beam focused from the substrate 1 side, it is susceptible to dust, and if it is 5 mm or more, it becomes difficult to increase the numerical aperture of the objective lens, and the irradiation light beam spot size becomes smaller. As a result, it becomes difficult to increase the recording density. The substrate 1 may be flexible or rigid. The flexible substrate 1 has a tape shape, a sheet shape,
Use in card form. The rigid substrate 1 has a card shape,
Or use it in the form of a disk. In addition, these substrates 1
After forming the recording layer 4 and the like, using two substrates,
An air sandwich structure, an air incident structure, or a close bonding structure may be used.
【００２３】本発明になる光ディスク１０の記録に用い
る光源としては、レーザ光を用いることが好ましく、主
に近赤外域の波長８３０ｎｍから紫外域の３００ｎｍの
範囲にあるものを使用する。１次光を２次高調波発生素
子（ＳＨＧ素子）を用いて短波長化した光源を利用する
こともできる。As a light source used for recording on the optical disk 10 according to the present invention, a laser beam is preferably used, and a light source having a wavelength of 830 nm in the near infrared region to 300 nm in the ultraviolet region is mainly used. It is also possible to use a light source in which the primary light is shortened in wavelength using a secondary harmonic generation element (SHG element).
【００２４】本発明になる光ディスク１０の記録は結晶
状態の記録層４にレーザ光パルスなどを照射してアモル
ファス（非晶状態）の記録マークを形成して行う。ま
た、反対に非晶状態の記録層４に結晶状態の記録マーク
を形成してもよい。消去はレーザ光照射によって、アモ
ルファスの記録マークを結晶化するか、もしくは、結晶
状態の記録マークをアモルファス化して行うことができ
る。実用的には、結晶化を引き起こす低エネルギーの消
去パワーの上に重畳した記録ピークパワーを記録層４に
投入することにより消去過程を経ることなくすでに記録
された記録マーク上にオーバーライトする。The recording of the optical disk 10 according to the present invention is performed by irradiating a laser beam pulse or the like to the recording layer 4 in a crystalline state to form an amorphous (amorphous) recording mark. Alternatively, a recording mark in a crystalline state may be formed on the recording layer 4 in an amorphous state. Erasing can be performed by irradiating a laser beam to crystallize an amorphous recording mark or to make a crystalline recording mark amorphous. Practically, a recording peak power superimposed on a low-energy erasing power causing crystallization is applied to the recording layer 4 to overwrite the already-recorded recording mark without going through the erasing process.
【００２５】[0025]
【実施例】次に、前述した構成の本発明になる光ディス
ク１０の製造方法について述べる。反射層２、記録層
４、誘電体層３，５などを基板１上に形成する方法とし
ては、公知の真空中での薄膜形成法、例えば真空蒸着法
（抵抗加熱型や電子ビーム型）、イオンプレーティング
法、スパッタリング法（直流や交流スパッタリング、反
応性スパッタリング、イオンビームスパッタリング）な
どがあげられる。特に組成、膜厚のコントロールが容易
であることから、スパッタリング法が好ましい。Next, a method of manufacturing the optical disk 10 according to the present invention having the above-described configuration will be described. As a method for forming the reflective layer 2, the recording layer 4, the dielectric layers 3, 5 and the like on the substrate 1, a known thin film forming method in a vacuum, for example, a vacuum deposition method (resistance heating type or electron beam type), Examples include an ion plating method and a sputtering method (DC or AC sputtering, reactive sputtering, or ion beam sputtering). In particular, the sputtering method is preferable because the composition and the film thickness can be easily controlled.
【００２６】スパッタリング法では、例えば、記録材料
と添加材料を各々のターゲットを同時にスパッタするこ
とにより容易に混合状態の記録層４を形成することがで
きる。成膜前の真空度は、１×１０-4Ｐａ以下にするの
が好ましい。真空槽内で複数の基板を同時に成膜するバ
ッチ式や基板を１枚ずつ処理する枚葉式成膜装置を使う
ことが好ましい。形成する反射層２、記録層４、誘電体
層３，５などの厚さの制御は、スパッタ電源の投入パワ
ーと時間を制御したり、水晶振動型膜厚計などで、堆積
状態をモニタリングすることで、容易に行える。In the sputtering method, for example, the recording layer 4 in a mixed state can be easily formed by simultaneously sputtering the recording material and the additive material on the respective targets. The degree of vacuum before film formation is preferably set to 1 × 10 −4 Pa or less. It is preferable to use a batch type film forming apparatus for simultaneously forming a plurality of substrates in a vacuum chamber or a single wafer type film forming apparatus for processing substrates one by one. The thickness of the reflective layer 2, the recording layer 4, the dielectric layers 3 and 5, etc. to be formed is controlled by controlling the power and time of a sputter power supply, and monitoring the deposition state with a quartz vibrating type film thickness meter. Thus, it can be easily performed.
【００２７】反射層２、記録層４、誘電体層３，５など
の形成は、基板１を固定したまま、あるいは移動、回転
した状態のどちらでもよい。膜厚の面内の均一性に優れ
ることから、基板１を自転させることが好ましく、さら
に公転を組合わせることが、より好ましい。必要に応じ
て基板１の冷却を行うと反り量を減少することができ
る。The formation of the reflection layer 2, the recording layer 4, the dielectric layers 3, 5 and the like may be performed while the substrate 1 is fixed, or may be moved or rotated. The substrate 1 is preferably rotated on its own axis because of excellent in-plane uniformity of the film thickness, and more preferably combined with revolution. When the substrate 1 is cooled as required, the amount of warpage can be reduced.
【００２８】次に、実施例のさらなる具体例につき説明
するが、本発明はこの具体例に限定されるものではな
い。Next, further specific examples of the embodiments will be described, but the present invention is not limited to these specific examples.
【００２９】[0029]
【実施例１】波長６５０ｎｍのレーザダイオード、ＮＡ
＝０．６０の光学レンズを搭載した光ディスクドライブ
テスタを用いて記録（１ビーム・オーバーライト）を行
った。再生光パワーＰｒは０．７ｍＷで線速によらず一
定とした。線速度３．５ｍ／ｓで変調信号のランダムパ
ターンによる評価を行なった。再生信号の振幅の中心で
スライスし、クロック・トゥー・データ・ジッタclock
to data jitterを測定した。媒体は、直径１２０ｍｍ、
板厚１．２ｍｍのポリカーボネイト樹脂基板上に形成し
た。基板は、トラックピッチが０．７４μｍ（グルーブ
ピッチ１．４８μｍ）、グルーブ記録を行った。溝深さ
は８０ｎｍでグルーブ幅とランド幅の比は、およそ４
６：５４であった。Embodiment 1 Laser diode with wavelength of 650 nm, NA
Recording (one-beam overwriting) was performed using an optical disk drive tester equipped with an optical lens of = 0.60. The reproducing light power Pr was constant at 0.7 mW regardless of the linear velocity. Evaluation was performed at a linear velocity of 3.5 m / s using a random pattern of the modulation signal. Slice at the center of the amplitude of the playback signal, clock-to-data jitter
to data jitter was measured. The medium has a diameter of 120 mm,
It was formed on a polycarbonate resin substrate having a thickness of 1.2 mm. The substrate was subjected to groove recording with a track pitch of 0.74 μm (groove pitch 1.48 μm). The groove depth is 80 nm and the ratio of the groove width to the land width is about 4
6:54.
【００３０】基板１を毎分６０回転で遊星回転させなが
ら、その上にスパッタリング法により、反射層２、第１
誘電体層３、記録層４、第２誘電体層５の順に真空成膜
を行った。まず、真空チャンバー内を６×１０-5Ｐａま
で排気した後、１．６×１０ -1ＰａのＡｒガスを導入し
た。Ａｇ、Ｃｕ，Ｐｄからなる３元素単一ターゲットを
直流スパッタ法にて、組成Ａｇ０．９７、Ｃｕ０．０
２、Ｐｄ０．０１の厚さ７５ｎｍの反射層２を形成し
た。While rotating the substrate 1 on the planet at 60 revolutions per minute,
The reflective layer 2 and the first
Vacuum film formation in the order of the dielectric layer 3, the recording layer 4, and the second dielectric layer 5
Was done. First, 6 × 10-FivePa
1.6 × 10 -1Ar gas of Pa is introduced
Was. Ag, Cu, Pd
The composition Ag 0.97, Cu 0.0
2. forming a reflective layer 2 having a thickness of 75 nm and a Pd of 0.01;
Was.
【００３１】ＳｉＯ2を２０ｍｏｌ％添加したＺｎＳ
を、高周波マグネトロンスパッタ法により反射層２上に
膜厚１７ｎｍの第１誘電体層３として形成した。続い
て、Ａｇ、Ｉｎ、Ｓｂ、Ｔｅからなる４元素単一ターゲ
ット（直径２インチ、厚さ３ｍｍ）を直流電源で下記の
組成を用いてスパッタリングして記録層４を形成した。
すなわち、具体的組成としては、Ａｇ０．０５、Ｉｎ
０．０５、Ｓｂ０．６１、Ｔｅ０．２９の膜厚２３ｎｍ
の記録層４を形成した。組成分析は同様の記録層４を別
に１００ｎｍの厚さでシリコン基板上に形成し、これを
ＩＣＰ発光分析法により分析した。さらに第１誘電体層
３と同様の材質の第２誘電体層５を７０ｎｍ形成した。ZnS to which 20 mol% of SiO 2 is added
Was formed as a first dielectric layer 3 having a thickness of 17 nm on the reflective layer 2 by a high-frequency magnetron sputtering method. Subsequently, a recording element 4 was formed by sputtering a four-element single target (diameter: 2 inches, thickness: 3 mm) composed of Ag, In, Sb, and Te using a DC power supply with the following composition.
That is, as a specific composition, Ag 0.05, In
23 nm thickness of 0.05, Sb0.61, Te0.29
Was formed. In the composition analysis, a similar recording layer 4 was separately formed with a thickness of 100 nm on a silicon substrate, and this was analyzed by ICP emission spectrometry. Further, a second dielectric layer 5 of the same material as that of the first dielectric layer 3 was formed to a thickness of 70 nm.
【００３２】このようにして形成した光ディスクを真空
容器より取り出した後、第２誘電体層５にアクリル系紫
外線硬化樹脂を基板１の内周側から外周側へ順次滴下
し、厚さ１００μｍのポリカーボートシートをその上の
乗せ、紫外線硬化樹脂が基板、シート間に十分行きわた
る様にスピン回転し、紫外線照射により硬化させて透明
層６を形成し、本発明の光ディスク１０を得た。After the optical disk thus formed is taken out of the vacuum container, an acrylic UV curable resin is sequentially dropped on the second dielectric layer 5 from the inner peripheral side to the outer peripheral side of the substrate 1 to form a 100 μm thick polycarbonate. The boat sheet was placed thereon, and the ultraviolet curable resin was spin-rotated so as to sufficiently spread between the substrate and the sheet, and was cured by irradiation with ultraviolet light to form the transparent layer 6, thereby obtaining the optical disc 10 of the present invention.
【００３３】[0033]
【比較例】比較例として、反射層２をＡｌ０．９７、Ｃ
ｒ０．０３の組成からなり膜厚１５０ｎｍとし、それ以
外は上記と全く同構成の光ディスクを作製した。こうし
て作製した光ディスクに、レーザ光やフラッシュランプ
等を照射して、記録層４を結晶化温度以上に加熱し初期
化処理を行った。Comparative Example As a comparative example, the reflection layer 2 was made of Al 0.97, C
An optical disk having a composition of r0.03 and a film thickness of 150 nm and having the same configuration as that described above except for the above was produced. The optical disk thus manufactured was irradiated with a laser beam, a flash lamp, or the like to heat the recording layer 4 to a temperature higher than the crystallization temperature and to perform an initialization process.
【００３４】透明（光透過）層６側から相変化記録層４
の案内溝であるグルーブ部に記録を行った。グルーブ
は、レーザ光の入射方向からみて凹状になっている。繰
り返しダイレクト・オーバー・ライト（ＤＯＷ）を行う
と記録層４の物質が移動して膜厚が薄くなったり、不純
物の拡散混入により再生信号の変調度が減少することが
知られている。繰り返しダイレクト・オーバー・ライト
を行った時の結果を、実施例、比較例として、そのそれ
ぞれについて図２に示す。From the transparent (light transmitting) layer 6 side, the phase change recording layer 4
The recording was performed in the groove portion which is the guide groove of No. 1. The groove is concave when viewed from the direction of incidence of the laser beam. It is known that, when repeated direct overwrite (DOW) is performed, the substance of the recording layer 4 moves to reduce the film thickness, or the degree of modulation of the reproduced signal decreases due to diffusion and mixing of impurities. FIG. 2 shows the results of repeated direct overwrite as examples and comparative examples.
【００３５】図２は、反射層２の組成と繰り返しオーバ
ライトとの関係を示す説明図である。図２において、ジ
ッタは、記録マーク始端（ＬＥ）と終端（ＴＥ）の二乗
平均である。本発明になる光ディスク１０は、比較例に
示した光ディスクと比べ、イニシャル記録からジッタ値
が低く抑えられ、１０００回書き換えた後も出力は一定
値を示し、記録層４の物質移動による出力の低下は認め
られない。ジッタと出力ともに５０００回にわたって劣
化が生じなかった。ランド部も同様な記録再生特性が得
られた。本発明になる光ディスク１０が、良好な繰返し
記録耐久性を有していることが明らかになった。なお、
図２において、○：ＤＯＷ５０００回後ジッタ１１％以
下、◎：ＤＯＷ５０００回後ジッタ９％以下を示すもの
である。FIG. 2 is an explanatory diagram showing the relationship between the composition of the reflective layer 2 and the repeated overwriting. In FIG. 2, the jitter is the mean square of the start (LE) and end (TE) of the recording mark. The optical disc 10 according to the present invention has a lower jitter value from the initial recording as compared with the optical disc shown in the comparative example, the output shows a constant value even after rewriting 1,000 times, and the output decreases due to mass transfer of the recording layer 4. It is not allowed. Both jitter and output did not deteriorate 5000 times. The same recording and reproduction characteristics were obtained in the land portion. It has been clarified that the optical disc 10 according to the present invention has good repetitive recording durability. In addition,
In FIG. 2, ○: jitter of 11% or less after 5000 times of DOW, ◎: jitter of 9% or less after 5000 times of DOW.
【００３６】本発明になる光ディスク１０は、熱伝導率
の大なるＡｇ合金反射層から構成されるため、従来用い
られているＡｌ及びＡｌ系合金反射層に較べ、反射層２
の薄膜化が可能となった。その結果、本発明のＡｇ合金
反射層においては、従来のように粒界の粗大化が進行す
る前に所定膜厚の形成が終了するため、基板１の平滑性
が反射層２上に維持される。従って、透明層６から入射
したレーザ光（図示せず）は、反射層２で損失無く反射
もしくは反射放熱され、良好な記録再生特性が得られる
ことが確認された。Since the optical disk 10 according to the present invention is composed of an Ag alloy reflective layer having a high thermal conductivity, the optical disk 10 has a reflective layer 2 compared to the conventionally used Al and Al-based alloy reflective layers.
Can be made thinner. As a result, in the Ag alloy reflective layer of the present invention, since the formation of the predetermined thickness is completed before the grain boundary coarsens as in the related art, the smoothness of the substrate 1 is maintained on the reflective layer 2. You. Accordingly, it was confirmed that the laser light (not shown) incident from the transparent layer 6 was reflected or reflected and radiated by the reflection layer 2 without loss, and good recording / reproducing characteristics were obtained.
【００３７】[0037]
【実施例２】反射層２の組成をＡｇ０．９８、Ｃｕ０．
０１、Ｐｄ０．０１とし、膜厚構成を反射層２を１００
ｎｍ、第１誘電体層３を１６ｎｍ、記録層４を２２ｎ
ｍ、第２誘電体層５を７１ｎｍとし、記録層４組成をＡ
ｇ０．０３、Ａｌ０．０４、Ｔｅ０．２８、Ｓｂ０．６
５にした以外は、前記した実施例１と同様にして透明層
６を設け、記録再生特性を調べた。使用した基板１は、
板厚０．６ｍｍ、溝深さは３０ｎｍ、ランド・グルーブ
幅の比は５５／４５、連続溝でトラックピッチは、０．
７４μｍである。初期化は、実施例１と同様に行った。EXAMPLE 2 The composition of the reflective layer 2 was Ag 0.98, Cu 0.
01, Pd0.01, and the thickness of the reflective layer 2 is 100
nm, the first dielectric layer 3 is 16 nm, and the recording layer 4 is 22 n
m, the second dielectric layer 5 is 71 nm, and the composition of the recording layer 4 is A
g 0.03, Al 0.04, Te 0.28, Sb 0.6
A transparent layer 6 was provided in the same manner as in Example 1 except that the recording layer was set to 5, and recording / reproducing characteristics were examined. The used substrate 1 is
The plate thickness is 0.6 mm, the groove depth is 30 nm, the land / groove width ratio is 55/45, and the track pitch is 0.1 in a continuous groove.
74 μm. Initialization was performed in the same manner as in Example 1.
【００３８】８-１６変調ランダムパターンを記録し、
再生信号の振幅の中心でスライスしてクロック・トゥー
・データ・ジッタ clock to data jitter を測定した。
その測定結果を図２に示す。図２より明らかな如く、１
０００回オーバーライト後のジッタはイニシャルジッタ
とほぼ同等で、５０００回後もジッタ、出力ともに劣化
が認められず、良好な繰り返し書換特性を示した。（図
２において、○：ＤＯＷ５０００回後ジッタ１１％以
下、◎：ＤＯＷ５０００回後ジッタ９％以下を示す）Recording an 8-16 modulation random pattern,
Clock to data jitter was measured by slicing at the center of the amplitude of the reproduced signal.
FIG. 2 shows the measurement results. As is clear from FIG.
The jitter after overwriting 000 times was almost equal to the initial jitter, and after 5,000 times, no deterioration was observed in both jitter and output, indicating good repetitive rewriting characteristics. (In FIG. 2, ○: jitter of 11% or less after 5000 times of DOW, ◎: jitter of 9% or less after 5000 times of DOW)
【００３９】[0039]
【実施例３】反射層２の組成をＡｇ０．９８、Ｃｕ０．
０１、Ｐｄ０．０１とし、膜厚構成は反射層２を５０ｎ
ｍ、第１誘電体層３を１８ｎｍ、記録層４を２０ｎｍ、
第２誘電体層５を６５ｎｍとし、記録層４組成をＡｇ
０．０４、Ａｌ０．０３、Ｔｅ０．２６、Ｓｂ０．６７
にした以外は、前記した実施例１と同様にして透明層６
を設け、記録再生特性を調べた。使用した基板１は、板
厚１．２ｍｍ、溝深さは４０ｎｍ、ランド・グルーブ幅
の比は５０／５０、連続溝でトラックピッチは、０．６
０μｍである。初期化は、実施例１と同様に行った。Example 3 The composition of the reflective layer 2 was Ag 0.98, Cu 0.
01, Pd0.01, and the thickness of the reflective layer 2 is 50 n.
m, the first dielectric layer 3 is 18 nm, the recording layer 4 is 20 nm,
The second dielectric layer 5 has a thickness of 65 nm, and the composition of the recording layer 4 is Ag.
0.04, Al 0.03, Te 0.26, Sb 0.67
Except that the transparent layer 6 was formed in the same manner as in Example 1 described above.
And the recording / reproducing characteristics were examined. The substrate 1 used had a thickness of 1.2 mm, a groove depth of 40 nm, a land / groove width ratio of 50/50, and a continuous groove with a track pitch of 0.6.
0 μm. Initialization was performed in the same manner as in Example 1.
【００４０】８-１６変調ランダムパターンを記録し、
再生信号の振幅の中心でスライスしてクロック・トゥー
・データ・ジッタを測定した。その測定結果を図２に示
す。図２より明らかな如く、１０００回オーバーライト
後のジッタはイニシャルジッタとほぼ同等で、５０００
回後もわずかな増加に留まり、良好な繰り返し書換特性
を示した。（図２において、○：ＤＯＷ５０００回後ジ
ッタ１１％以下、◎：ＤＯＷ５０００回後ジッタ９％以
下を示す）Recording an 8-16 modulation random pattern,
Clock to data jitter was measured by slicing at the center of the amplitude of the reproduced signal. FIG. 2 shows the measurement results. As apparent from FIG. 2, the jitter after overwriting 1000 times is almost equal to the initial jitter, and
Even after the number of times, the increase was only slight, indicating good repetitive rewriting characteristics. (In FIG. 2, ○: jitter of 11% or less after 5000 times of DOW, ◎: jitter of 9% or less after 5000 times of DOW)
【００４１】[0041]
【実施例４】反射層２の組成をＡｇ０．９５、Ｐｄ０．
０５とし、膜厚構成は反射層２を８０ｎｍ、第１誘電体
層３を１６ｎｍ、記録層４を２０ｎｍ、第２誘電体層５
を７０ｎｍとし、記録層４組成をＡｇ０．０４、Ａｌ
０．０３、Ｔｅ０．２６、Ｓｂ０．６７にした以外は、
前記した実施例１と同様にして透明層６を設け、記録再
生特性を調べた。使用した基板１は、板厚０．６ｍｍ、
溝深さは４０ｎｍ、ランド・グルーブ幅の比は５５／４
５、連続溝でトラックピッチは、０．６０μｍである。
初期化は、実施例１と同様に行った。Example 4 The composition of the reflective layer 2 was Ag 0.95, Pd0.
05, the reflective layer 2 has a thickness of 80 nm, the first dielectric layer 3 has a thickness of 16 nm, the recording layer 4 has a thickness of 20 nm, and the second dielectric layer 5 has a thickness of 80 nm.
Was 70 nm, the composition of the recording layer 4 was Ag 0.04,
0.03, Te0.26 and Sb0.67 except
The transparent layer 6 was provided in the same manner as in Example 1, and the recording / reproducing characteristics were examined. The substrate 1 used had a thickness of 0.6 mm,
The groove depth is 40 nm, and the land / groove width ratio is 55/4.
5. The track pitch in the continuous groove is 0.60 μm.
Initialization was performed in the same manner as in Example 1.
【００４２】８-１６変調ランダムパターンを記録し、
再生信号の振幅の中心でスライスしてクロック・トゥー
・データ・ジッタを測定した。その測定結果を図２に示
す。図２より明らかな如く、１０００回オーバーライト
後のジッタはイニシャルジッタとほぼ同等で、５０００
回後もわずかな増加に留まり、良好な繰り返し書換特性
を示した。（図２において、○：ＤＯＷ５０００回後ジ
ッタ１１％以下、◎：ＤＯＷ５０００回後ジッタ９％以
下を示す）Recording an 8-16 modulation random pattern,
Clock to data jitter was measured by slicing at the center of the amplitude of the reproduced signal. FIG. 2 shows the measurement results. As apparent from FIG. 2, the jitter after overwriting 1000 times is almost equal to the initial jitter, and
Even after the number of times, the increase was only slight, indicating good repetitive rewriting characteristics. (In FIG. 2, ○: jitter of 11% or less after 5000 times of DOW, ◎: jitter of 9% or less after 5000 times of DOW)
【００４３】[0043]
【実施例５】反射層２の組成をＡｇ０．９９５、Ｃｕ
０．００５とし、膜厚構成は反射層２を８０ｎｍ、第１
誘電体層３を１６ｎｍ、記録層４を２０ｎｍ、第２誘電
体層５を６５ｎｍとし、記録層４組成をＡｇ０．０４、
Ａｌ０．０３、Ｔｅ０．２６、Ｓｂ０．６７にした以外
は、前記した実施例１と同様にして透明層６を設け、記
録再生特性を調べた。使用した基板１は、板厚０．６ｍ
ｍ、溝深さは４０ｎｍ、ランド・グルーブ幅の比は５０
／５０、連続溝でトラックピッチは、０．６０μｍであ
る。初期化は、実施例１と同様に行った。Example 5 The composition of the reflective layer 2 was Ag 0.995, Cu
The thickness of the reflective layer 2 is set to 80 nm,
The dielectric layer 3 was 16 nm, the recording layer 4 was 20 nm, the second dielectric layer 5 was 65 nm, the composition of the recording layer 4 was Ag 0.04,
A transparent layer 6 was provided in the same manner as in Example 1 except that Al 0.03, Te 0.26, and Sb 0.67 were used, and the recording / reproducing characteristics were examined. The substrate 1 used was 0.6 m thick.
m, groove depth is 40 nm, land / groove width ratio is 50
/ 50, the track pitch in the continuous groove is 0.60 μm. Initialization was performed in the same manner as in Example 1.
【００４４】８-１６変調ランダムパターンを記録し、
再生信号の振幅の中心でスライスしてクロック・トゥー
・データ・ジッタを測定した。その測定結果を図２に示
す。図２より明らかな如く、１０００回オーバーライト
後のジッタはイニシャルジッタとほぼ同等で、５０００
回後もわずかな増加に留まり、良好な繰り返し書換特性
を示した。（図２において、○：ＤＯＷ５０００回後ジ
ッタ１１％以下、◎：ＤＯＷ５０００回後ジッタ９％以
下を示す）Recording an 8-16 modulation random pattern,
Clock to data jitter was measured by slicing at the center of the amplitude of the reproduced signal. FIG. 2 shows the measurement results. As apparent from FIG. 2, the jitter after overwriting 1000 times is almost equal to the initial jitter, and
Even after the number of times, the increase was only slight, indicating good repetitive rewriting characteristics. (In FIG. 2, ○: jitter of 11% or less after 5000 times of DOW, ◎: jitter of 9% or less after 5000 times of DOW)
【００４５】[0045]
【発明の効果】上述した構成を有する本発明の光ディス
クは、多数回の記録消去を繰り返しても、記録消去動作
が安定しており、特性の劣化、欠陥の発生がほとんどな
い良好な繰り返し記録特性が得られる。また、本発明の
光ディスクは、スパッタリング法により容易に作製でき
ると共に、反射層を薄くすることが可能であり、生産効
率が向上する。According to the optical disk of the present invention having the above-described structure, the recording and erasing operation is stable even when recording and erasing are repeated a large number of times, and good repetitive recording characteristics with little deterioration of characteristics and almost no defects are generated. Is obtained. Further, the optical disk of the present invention can be easily manufactured by the sputtering method, and the reflection layer can be thinned, so that the production efficiency is improved.
【図１】本発明に係る光学的情報記録媒体の一実施例を
示す断面図である。FIG. 1 is a sectional view showing one embodiment of an optical information recording medium according to the present invention.
【図２】反射層の組成と繰り返しオーバライトとの関係
を示す図である。FIG. 2 is a diagram showing the relationship between the composition of a reflective layer and repeated overwriting.
１ 基板 ２ 反射層 ３ 第１誘電体層 ４ 記録層 ５ 第２誘電体層 ６ 透明層 １０ 光学的情報記録媒体 DESCRIPTION OF SYMBOLS 1 Substrate 2 Reflective layer 3 1st dielectric layer 4 Recording layer 5 2nd dielectric layer 6 Transparent layer 10 Optical information recording medium
Claims (1)
層、少なくとも一層の誘電体層、相変化型記録層、少な
くとも一層の誘電体層、光透過層を順次積層してなり、
光の照射により前記記録層を構成する原子の配列が変化
して情報の記録及び消去が行われる光学的情報記録媒体
であって、前記反射層はＡｇを主成分とし、Ａｇ１-ａ
Ｍａとしたとき（ＭはＡｌ、Ａｕ，Ｃｕ，Ｃｏ，Ｎｉ，
Ｔｉ，Ｖ，Ｍｏ，Ｍｎ，Ｐｔ，Ｓｉ，Ｎｂ，Ｆｅ，Ｔ
ａ，Ｈｆ，Ｇａ，Ｐｄ，Ｂｉ，Ｉｎ，Ｗ，Ｚｒから選ば
れた少なくとも一つの元素）、その組成が０．００５≦
ａ≦０．０５（ａ：Ｍの原子比の合計）を満たし、厚さ
が５０ｎｍ以上、１００ｎｍ以下であることを特徴とす
る光学的情報記録媒体。A reflective layer, at least one dielectric layer, a phase-change recording layer, at least one dielectric layer, and a light-transmitting layer, which are sequentially laminated on a substrate having an uneven portion;
An optical information recording medium in which the arrangement of atoms constituting the recording layer is changed by irradiation of light to record and erase information, wherein the reflective layer has Ag as a main component and Ag1-a
Ma (where M is Al, Au, Cu, Co, Ni,
Ti, V, Mo, Mn, Pt, Si, Nb, Fe, T
a, at least one element selected from Hf, Ga, Pd, Bi, In, W, and Zr) whose composition is 0.005 ≦
An optical information recording medium, wherein a ≦ 0.05 (total atomic ratio of a: M) is satisfied, and the thickness is 50 nm or more and 100 nm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP36245999A JP2001184725A (en) | 1999-12-21 | 1999-12-21 | Optical information recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP36245999A JP2001184725A (en) | 1999-12-21 | 1999-12-21 | Optical information recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001184725A true JP2001184725A (en) | 2001-07-06 |
Family
ID=18476909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP36245999A Pending JP2001184725A (en) | 1999-12-21 | 1999-12-21 | Optical information recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001184725A (en) |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003085838A (en) * | 2001-09-14 | 2003-03-20 | Tdk Corp | Method of manufacturing optical recording medium |
| FR2856803A1 (en) * | 2003-06-27 | 2004-12-31 | Kobe Steel Ltd | AG ALLOY REFLECTIVE FILM FOR REFLECTORS AND REFLECTOR PROVIDED WITH SAME |
| JP2006286097A (en) * | 2005-03-31 | 2006-10-19 | Toshiba Corp | Storage medium, reproduction method, and recording method |
| US7241549B2 (en) | 2001-09-18 | 2007-07-10 | Ricoh Company, Ltd. | Information recording medium |
| US7349324B2 (en) | 2002-04-19 | 2008-03-25 | Victor Company Of Japan, Limited | Reproducing system and corresponding information recording medium having wobbled land portions |
| US7413618B2 (en) * | 2003-12-10 | 2008-08-19 | Tanaka Kikinzoku Kogyo K.K. | Silver alloy for reflective film |
| US7419711B2 (en) | 2002-08-08 | 2008-09-02 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7476431B2 (en) | 2005-04-14 | 2009-01-13 | Kobe Steel, Ltd. | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7517575B2 (en) | 2005-07-22 | 2009-04-14 | Kobe Steel, Ltd. | Optical information recording media and silver alloy reflective films for the same |
| US7645500B2 (en) * | 2003-04-18 | 2010-01-12 | Target Technology Company, Llc | Metal alloys for the reflective or the semi-reflective layer of an optical storage medium |
| US7695792B2 (en) | 2005-07-22 | 2010-04-13 | Kobe Steel, Ltd. | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7713608B2 (en) | 2005-07-22 | 2010-05-11 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7767041B2 (en) * | 2003-05-16 | 2010-08-03 | Kabushiki Kaisha Kobe Seiko Sho | Ag-Bi-base alloy sputtering target, and method for producing the same |
| US7790263B2 (en) | 2005-12-21 | 2010-09-07 | Sony Corporation | Ag alloy reflective film for optical information recording medium, optical information recording medium and Ag alloy sputtering target for forming Ag alloy reflective film for optical information recording medium |
| US7843796B2 (en) | 2006-05-16 | 2010-11-30 | Sony Corporation | Optical information recording medium and method of marking BCA (burst cutting area) into the same |
| US8092889B2 (en) | 2006-08-28 | 2012-01-10 | Kobe Steel, Ltd. | Silver alloy reflective film for optical information storage media, optical information storage medium, and sputtering target for the deposition of silver alloy reflective film for optical information storage media |
| US8152976B2 (en) | 2007-08-29 | 2012-04-10 | Kobelco Research Institute, Inc. | AG-based alloy sputtering target |
| US8309195B2 (en) | 2007-09-19 | 2012-11-13 | Kobe Steel, Ltd. | Read-only optical information recording medium |
| US8431931B2 (en) | 2008-11-10 | 2013-04-30 | Kobe Steel, Ltd. | Reflective anode and wiring film for organic EL display device |
| US8470426B2 (en) | 2008-09-11 | 2013-06-25 | Kobe Steel, Ltd. | Read-only optical information recording medium and sputtering target for depositing reflective film for the optical information recording medium |
| US8530023B2 (en) | 2009-04-14 | 2013-09-10 | Kobe Steel, Ltd. | Optical information recording medium and sputtering target for forming reflective film for optical information recording medium |
-
1999
- 1999-12-21 JP JP36245999A patent/JP2001184725A/en active Pending
Cited By (39)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003085838A (en) * | 2001-09-14 | 2003-03-20 | Tdk Corp | Method of manufacturing optical recording medium |
| US7241549B2 (en) | 2001-09-18 | 2007-07-10 | Ricoh Company, Ltd. | Information recording medium |
| US7907504B2 (en) | 2002-04-19 | 2011-03-15 | Victor Company Of Japan Limited | Optical recording medium having auxiliary information and reference clock |
| US7656781B2 (en) | 2002-04-19 | 2010-02-02 | Victor Company Of Japan, Limited | Reproducing system and corresponding information recording medium having wobbled land portions |
| US8179773B2 (en) | 2002-04-19 | 2012-05-15 | JVC Kenwood Corporation | Optical recording medium having auxiliary information and reference clock |
| US7349324B2 (en) | 2002-04-19 | 2008-03-25 | Victor Company Of Japan, Limited | Reproducing system and corresponding information recording medium having wobbled land portions |
| US8189451B2 (en) | 2002-04-19 | 2012-05-29 | JVC Kenwood Corporation | Optical recording medium having auxiliary information and reference clock |
| US7668072B2 (en) | 2002-04-19 | 2010-02-23 | Victor Company Of Japan, Limited | Producing system and corresponding information recording medium having wobbled land portions |
| US7514037B2 (en) | 2002-08-08 | 2009-04-07 | Kobe Steel, Ltd. | AG base alloy thin film and sputtering target for forming AG base alloy thin film |
| US8178174B2 (en) | 2002-08-08 | 2012-05-15 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US8936856B2 (en) | 2002-08-08 | 2015-01-20 | Kobe Steel, Ltd. | AG base alloy thin film and sputtering target for forming AG base alloy thin film |
| US7566417B2 (en) * | 2002-08-08 | 2009-07-28 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7871686B2 (en) | 2002-08-08 | 2011-01-18 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| DE10362283B4 (en) | 2002-08-08 | 2018-05-30 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Production method for Ag alloy based film and sputtering target |
| US7419711B2 (en) | 2002-08-08 | 2008-09-02 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7758942B2 (en) | 2002-08-08 | 2010-07-20 | Kabushiki Kaisha Kobe Seiko Sho | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7776420B2 (en) | 2002-08-08 | 2010-08-17 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7722942B2 (en) | 2002-08-08 | 2010-05-25 | Kobe Steel, Ltd. | Ag base alloy thin film and sputtering target for forming Ag base alloy thin film |
| US7645500B2 (en) * | 2003-04-18 | 2010-01-12 | Target Technology Company, Llc | Metal alloys for the reflective or the semi-reflective layer of an optical storage medium |
| US7767041B2 (en) * | 2003-05-16 | 2010-08-03 | Kabushiki Kaisha Kobe Seiko Sho | Ag-Bi-base alloy sputtering target, and method for producing the same |
| US7203003B2 (en) | 2003-06-27 | 2007-04-10 | Kobe Steel, Ltd. | Reflective Ag alloy film for reflectors and reflector provided with the same |
| FR2856803A1 (en) * | 2003-06-27 | 2004-12-31 | Kobe Steel Ltd | AG ALLOY REFLECTIVE FILM FOR REFLECTORS AND REFLECTOR PROVIDED WITH SAME |
| US7413618B2 (en) * | 2003-12-10 | 2008-08-19 | Tanaka Kikinzoku Kogyo K.K. | Silver alloy for reflective film |
| US8232042B2 (en) | 2005-03-31 | 2012-07-31 | Kabushiki Kaisha Toshiba | Storage medium, reproducing method, and recording method |
| JP4575211B2 (en) * | 2005-03-31 | 2010-11-04 | 株式会社東芝 | Storage medium, reproducing method and recording method |
| JP2006286097A (en) * | 2005-03-31 | 2006-10-19 | Toshiba Corp | Storage medium, reproduction method, and recording method |
| US7754307B2 (en) | 2005-04-14 | 2010-07-13 | Kobe Steel, Ltd. | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7476431B2 (en) | 2005-04-14 | 2009-01-13 | Kobe Steel, Ltd. | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7713608B2 (en) | 2005-07-22 | 2010-05-11 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7695792B2 (en) | 2005-07-22 | 2010-04-13 | Kobe Steel, Ltd. | Silver alloy reflective films for optical information recording media, silver alloy sputtering targets therefor, and optical information recording media |
| US7517575B2 (en) | 2005-07-22 | 2009-04-14 | Kobe Steel, Ltd. | Optical information recording media and silver alloy reflective films for the same |
| US7790263B2 (en) | 2005-12-21 | 2010-09-07 | Sony Corporation | Ag alloy reflective film for optical information recording medium, optical information recording medium and Ag alloy sputtering target for forming Ag alloy reflective film for optical information recording medium |
| US7843796B2 (en) | 2006-05-16 | 2010-11-30 | Sony Corporation | Optical information recording medium and method of marking BCA (burst cutting area) into the same |
| US8092889B2 (en) | 2006-08-28 | 2012-01-10 | Kobe Steel, Ltd. | Silver alloy reflective film for optical information storage media, optical information storage medium, and sputtering target for the deposition of silver alloy reflective film for optical information storage media |
| US8152976B2 (en) | 2007-08-29 | 2012-04-10 | Kobelco Research Institute, Inc. | AG-based alloy sputtering target |
| US8309195B2 (en) | 2007-09-19 | 2012-11-13 | Kobe Steel, Ltd. | Read-only optical information recording medium |
| US8470426B2 (en) | 2008-09-11 | 2013-06-25 | Kobe Steel, Ltd. | Read-only optical information recording medium and sputtering target for depositing reflective film for the optical information recording medium |
| US8431931B2 (en) | 2008-11-10 | 2013-04-30 | Kobe Steel, Ltd. | Reflective anode and wiring film for organic EL display device |
| US8530023B2 (en) | 2009-04-14 | 2013-09-10 | Kobe Steel, Ltd. | Optical information recording medium and sputtering target for forming reflective film for optical information recording medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2001184725A (en) | Optical information recording medium | |
| JP2004255698A (en) | Optical recording medium | |
| WO1995026549A1 (en) | Optical recording medium and method of manufacturing the same | |
| JP2001126315A (en) | Optical information recording medium | |
| JP2000190637A (en) | Optical information recording medium | |
| JPH07161071A (en) | Optical recording medium | |
| JP3087598B2 (en) | Optical recording medium | |
| JP3163943B2 (en) | Optical recording medium | |
| JP2001184723A (en) | Optical information recording medium | |
| JP2002230839A (en) | Optical recording medium | |
| JP3173177B2 (en) | Optical recording medium and manufacturing method thereof | |
| JPH07214913A (en) | Optical recording medium | |
| JPH07262607A (en) | Optical recording medium | |
| JPH07262613A (en) | Optical recording medium | |
| JP2001010232A (en) | Phase change type optical recording medium | |
| JPH1139709A (en) | Optical recording medium | |
| JP3216552B2 (en) | Optical recording medium and manufacturing method thereof | |
| JP2000190634A (en) | Optical information recording medium | |
| JP2000185466A (en) | Optical information recording medium | |
| JPH06127135A (en) | Optical record medium | |
| JP2000185467A (en) | Optical information recording medium | |
| JP2003248975A (en) | Phase change optical information recording medium | |
| JP2001121819A (en) | Optical information recording medium | |
| JPH10172180A (en) | Optical recording medium | |
| JP2003335063A (en) | Optical recording medium |