JPH0524572B2 - - Google Patents
Info
- Publication number
- JPH0524572B2 JPH0524572B2 JP62158918A JP15891887A JPH0524572B2 JP H0524572 B2 JPH0524572 B2 JP H0524572B2 JP 62158918 A JP62158918 A JP 62158918A JP 15891887 A JP15891887 A JP 15891887A JP H0524572 B2 JPH0524572 B2 JP H0524572B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- magneto
- optical recording
- recording
- substrate
- 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 - Fee Related
Links
- 239000000758 substrate Substances 0.000 claims description 13
- 229910052715 tantalum Inorganic materials 0.000 claims description 5
- 229910000838 Al alloy Inorganic materials 0.000 claims description 3
- 239000010410 layer Substances 0.000 description 35
- 239000010408 film Substances 0.000 description 11
- 230000035945 sensitivity Effects 0.000 description 10
- 238000000034 method Methods 0.000 description 7
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 229910044991 metal oxide Inorganic materials 0.000 description 4
- 150000004706 metal oxides Chemical class 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000005240 physical vapour deposition Methods 0.000 description 3
- 229910052761 rare earth metal Inorganic materials 0.000 description 3
- 150000002910 rare earth metals Chemical class 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- -1 TbFeCo Chemical class 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000004417 polycarbonate Substances 0.000 description 2
- 229920000515 polycarbonate Polymers 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 229910021332 silicide Inorganic materials 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052723 transition metal Inorganic materials 0.000 description 2
- 150000003624 transition metals Chemical class 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910002546 FeCo Inorganic materials 0.000 description 1
- 230000005374 Kerr effect Effects 0.000 description 1
- 229910016629 MnBi Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005566 electron beam evaporation Methods 0.000 description 1
- 238000001017 electron-beam sputter deposition Methods 0.000 description 1
- 238000007733 ion plating Methods 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910001004 magnetic alloy Inorganic materials 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
- 238000005546 reactive sputtering Methods 0.000 description 1
- FVBUAEGBCNSCDD-UHFFFAOYSA-N silicide(4-) Chemical compound [Si-4] FVBUAEGBCNSCDD-UHFFFAOYSA-N 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、光学的記録に用いる光磁気記録媒体
に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magneto-optical recording medium used for optical recording.
（従来の技術とその問題点）
光メモリー素子の中でも追加記録、消去が可能
な、イレーザブル型メモリーは、光磁気記録方式
が最も実用化に近い段階にいる。光磁気記録媒体
の記録層としては総合的な特性から見て、現在の
所、希土類、遷移金属薄膜が最も多く用いられて
いる。(Prior art and its problems) Among optical memory devices, magneto-optical recording is at the closest stage to practical use for erasable memory, which allows additional recording and erasure. At present, thin films of rare earth metals and transition metals are most often used as the recording layer of magneto-optical recording media in terms of overall characteristics.
この光磁気記録媒体として、レーザー光照射時
の記録・再生効率を向上させる為に基板上の光磁
気記録層上に反射層を設ける方式も提案されてい
る。この方式はカー効果とフアラデー効果の併用
により高いＣ／Ｎ比を得られるという点で優れて
いる。 As this magneto-optical recording medium, a method has also been proposed in which a reflective layer is provided on the magneto-optical recording layer on the substrate in order to improve the recording/reproduction efficiency during laser beam irradiation. This method is excellent in that a high C/N ratio can be obtained by combining the Kerr effect and the Faraday effect.
従来、反射層としてAlを用いるものや、Teを
用いるものが提案されている。（特開昭62−
52744）
しかしながら、Alを使用した場合にはその高
熱伝導性のため記録感度が大幅に低下し、また、
Teを用いた場合には記録感度は向上するが反射
率が低いため十分なＣ／Ｎ比が得られないという
欠点を有する。 Hitherto, methods using Al or Te as a reflective layer have been proposed. (Unexamined Japanese Patent Publication 1986-
52744) However, when Al is used, recording sensitivity decreases significantly due to its high thermal conductivity, and
When Te is used, the recording sensitivity is improved, but the reflectance is low, so a sufficient C/N ratio cannot be obtained.
（問題点を解決するための手段）
本発明者等は上述の欠点を克服した、高感度で
高Ｃ／Ｎ比の光磁気記録媒体を提供するべく鋭意
検討した結果、特定の物質で反射層を構成するこ
とにより記録感度が高く、キヤリアレベルが高
い、また経時安定性に優れた光磁気記録媒体が得
られることを見出した。(Means for Solving the Problems) As a result of intensive studies to provide a magneto-optical recording medium with high sensitivity and a high C/N ratio that overcomes the above-mentioned drawbacks, the inventors of the present invention have developed a reflective layer using a specific material. It has been found that a magneto-optical recording medium with high recording sensitivity, high carrier level, and excellent stability over time can be obtained by configuring the following.
本発明の要旨は、基板上に干渉層、光磁気記録
層および反射層を順次設けてなる光磁記録録媒体
において、反射層をTaを0.1〜15at％含有するAl
合金によつて形成したことを特徴とする光磁気記
録媒体に存する。
The gist of the present invention is to provide a magneto-optical recording medium in which an interference layer, a magneto-optical recording layer and a reflective layer are sequentially provided on a substrate, in which the reflective layer is made of aluminum containing 0.1 to 15 at% Ta.
A magneto-optical recording medium is characterized in that it is formed of an alloy.
以下、本発明を詳細に説明する。 The present invention will be explained in detail below.
まず、本発明において用いられる基板として
は、ガラス、アクリル樹脂、ポリカーボネート樹
脂等のプラスチツク、又はアルミニウム等の金
属、ガラス上に溝つき樹脂を形成した基板等が挙
げられる。 First, examples of the substrate used in the present invention include glass, plastic such as acrylic resin and polycarbonate resin, metal such as aluminum, and a substrate with grooved resin formed on glass.
基板の厚みは１〜２mm程度が一般的である。 The thickness of the substrate is generally about 1 to 2 mm.
光磁気記録層としては、たとえば、TbFe，
TbFeCo，TbCo，DyFeCoなどの希土類と遷移
金属の非晶質磁性合金、及びMnBi，MnCuBiな
どの多結晶垂直磁化膜が用いられる。特に希土系
の合金磁性膜に用いて大変効果的である。光磁気
記録層の膜厚は150〜100Å、好ましくは200〜500
Åである。 As the magneto-optical recording layer, for example, TbFe,
Amorphous magnetic alloys of rare earth and transition metals such as TbFeCo, TbCo, and DyFeCo, and polycrystalline perpendicular magnetization films such as MnBi and MnCuBi are used. It is particularly effective for use in rare earth alloy magnetic films. The thickness of the magneto-optical recording layer is 150 to 100 Å, preferably 200 to 500 Å.
It is Å.
本発明においては、上記基板と光磁気記録層の
間に干渉層を設ける。この層は高屈折率の透明膜
による光の干渉効果を用い反射率を落とすことで
ノイズを低下させＣ／Ｎ比を向上させるためのも
のである。干渉層は単層膜でも多層膜でもよい。
干渉層としては金属酸化物や金属チッ化物、無機
炭化物などが用いられる。金属酸化物としては
Al2O3，Ta2O5，SiO，SiO2の金属酸化物単独あ
るいはこれらの混合物、あるいはAl−Ta−Ｏの
複合酸化物等が挙げられる。また更にこれらに他
の元素、例えばTi，Zr，Ｗ，Mo，Yb等が酸化
物の形で単独あるいはAl−Taと複合して酸化物
を形成していてもよい。これらの金属酸化物は緻
密で外部からの水分や酸素の侵入を防ぎ、耐食性
が高く光磁気記録層との反応性も小であり、ま
た、基板として樹脂基板を使用する場合にも樹脂
との密着性に優れる。 In the present invention, an interference layer is provided between the substrate and the magneto-optical recording layer. This layer uses the light interference effect of a transparent film with a high refractive index to reduce reflectance, thereby reducing noise and improving the C/N ratio. The interference layer may be a single layer film or a multilayer film.
As the interference layer, metal oxides, metal nitrides, inorganic carbides, etc. are used. As a metal oxide
Examples include metal oxides such as Al 2 O 3 , Ta 2 O 5 , SiO, and SiO 2 alone or mixtures thereof, and composite oxides of Al-Ta-O. Further, other elements such as Ti, Zr, W, Mo, Yb, etc. may be added to these elements alone in the form of oxides or in combination with Al--Ta to form oxides. These metal oxides are dense and prevent moisture and oxygen from entering from the outside, have high corrosion resistance, and have low reactivity with the magneto-optical recording layer.Also, when using a resin substrate as a substrate, it is difficult to interact with the resin. Excellent adhesion.
金属チツ化物としては、具体的にはSi，Al，
Ge等の金属のチツ化物あるいはこれらの２種以
上の複合チツ化物又はこれらとNb，Taとの複合
チツ化物（例えば、SiNbN，SiTaN等）が挙げ
られる。なかでもSiを含有するチツ化物が良好な
結果をもたらす。 Specifically, the metal silicides include Si, Al,
Examples include titrides of metals such as Ge, composite titrides of two or more of these metals, and composite titrides of these and Nb and Ta (eg, SiNbN, SiTaN, etc.). Among them, titanium containing Si gives good results.
金属チツ化物は緻密で外部からの水分や酸素の
侵入を防ぎ、それ自身の耐食性が高く、光磁気記
録層との反応性が小である。 Metal silicide is dense and prevents moisture and oxygen from entering from the outside, has high corrosion resistance, and has low reactivity with the magneto-optical recording layer.
無機炭化物としてはB4Ｃ，SiC等が挙げられ
る。 Examples of the inorganic carbide include B 4 C and SiC.
この干渉層の膜厚は屈折率により最適膜厚が異
なるが、通常400Å〜1500Å程度、特に500Å〜
1000Åが適当である。 The optimal thickness of this interference layer varies depending on the refractive index, but it is usually about 400 Å to 1500 Å, especially 500 Å to 500 Å.
1000 Å is appropriate.
本発明においては光磁気記録層上にTaを含有
するAl合金からなる反射膜を設ける。Taの含有
量は0.1〜15原子％（at％）であることが必要で、
特に0.5〜10at％が好ましい。また、Al合金中に
他の元素例えばCu，Mn，Mg等を少量含有させ
ても良い。この反射層の厚さは100〜1000Å程度、
好ましくは200〜600Å程度である。厚すぎた場合
感度が低下し、薄すぎる場合には反射率が低下す
る。 In the present invention, a reflective film made of an Al alloy containing Ta is provided on the magneto-optical recording layer. The Ta content must be between 0.1 and 15 atomic percent (at%).
Particularly preferred is 0.5 to 10 at%. Further, a small amount of other elements such as Cu, Mn, Mg, etc. may be included in the Al alloy. The thickness of this reflective layer is approximately 100 to 1000 Å.
Preferably it is about 200 to 600 Å. If it is too thick, the sensitivity will decrease, and if it is too thin, the reflectance will decrease.
基板上に干渉層、記録層、反射層の各層を形成
するには、スパツタリング等の物理蒸着法
（PVD）、プラズマCVDのような化学蒸着法
（CVD）等が適用される。 Physical vapor deposition (PVD) such as sputtering, chemical vapor deposition (CVD) such as plasma CVD, etc. are used to form the interference layer, recording layer, and reflective layer on the substrate.
PVD法にて光磁気記録層、干渉層及び反射層
を成膜形成するには、所定の組成をもつたターゲ
ツトを用いて電子ビーム蒸着またはスパツタリン
グにより基板上に各層を堆積するのが通常の方法
である。 To form a magneto-optical recording layer, an interference layer, and a reflective layer using the PVD method, the usual method is to deposit each layer on a substrate by electron beam evaporation or sputtering using a target with a predetermined composition. It is.
また、イオンプレーテイングを用いる方法も考
えられる。 A method using ion plating is also considered.
膜の堆積速度は早すぎると膜応力を増加させ、
遅すぎれば生産性に影響するので通常0.1Å／sec
〜100Å／sec程度とされる。 If the film deposition rate is too fast, it will increase the film stress,
If it is too slow, it will affect productivity, so it is usually 0.1 Å/sec.
It is estimated to be about 100 Å/sec.
以下に実施例をもつて本発明を更に詳細に説明
するが本発明はその要旨を越えない限り以下の実
施例に限定されるものではない。
The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the invention is exceeded.
実施例 １
ポリカーボネート基板をスパツタリング装置に
導入し、先ず８×10-7torr以下まで排気し、Arと
O2との混合ガスを用いてTaターゲツトの反応性
スパツタを行いTa2O5からなる800Åの干渉層を
形成した。次いでTbターゲツト及びFeCoターゲ
ツトを用いたArガスによる２元同時スパツタに
よりTbFeCOの300Å記録層を設けた。更にTaチ
ツプを配置したAlターゲツトをArガス中でスパ
ツターし300Åの反射層を形成した。反射層中の
Ta量の調節はTaチツプの数を変えることにより
行つた。Example 1 A polycarbonate substrate was introduced into a sputtering device, and the temperature was first evacuated to 8×10 -7 torr or less, and then Ar and
Reactive sputtering of a Ta target was performed using a mixed gas with O 2 to form an 800 Å interference layer consisting of Ta 2 O 5 . Next, a 300 Å recording layer of TbFeCO was formed by dual simultaneous sputtering with Ar gas using a Tb target and a FeCo target. Furthermore, an Al target with Ta chips placed thereon was sputtered in Ar gas to form a 300 Å reflective layer. in the reflective layer
The amount of Ta was adjusted by changing the number of Ta chips.
この光磁気記録媒体をPINフオトダイオード差
動検出器をもつた動特性検出器により記録感度及
びキヤリア・レベル（Al膜を用いた場合を0dbと
する）を測定した。記録感度は、２次歪みが最小
のところの記録パワー（最適記録パワー）とし
た。 The recording sensitivity and carrier level (0 db when using an Al film) of this magneto-optical recording medium were measured using a dynamic characteristic detector equipped with a PIN photodiode differential detector. The recording sensitivity was set to the recording power (optimum recording power) at which the second-order distortion was minimum.
記録条件：CAV（定角速度）1800rpm
半径30mm位置、溝上記録
記録周波数0.5MHz
duty50％
再生条件：CAV1800rpm
再生パワー0.8mW
反射層の組成は螢光Ｘ線法により分析した。結
果を第１図に示した。最適記録パワーの低い媒体
ほど感度の良い媒体であり、キヤリア・レベルの
高い媒体ほど再生信号品質が高い。 Recording conditions: CAV (constant angular velocity) 1800 rpm, radius 30 mm position, groove recording Recording frequency 0.5 MHz duty 50% Reproducing conditions: CAV 1800 rpm Reproducing power 0.8 mW The composition of the reflective layer was analyzed by fluorescent X-ray method. The results are shown in Figure 1. A medium with a lower optimum recording power is a medium with higher sensitivity, and a medium with a higher carrier level has a higher reproduction signal quality.
又このデイスクを接着剤を用いて他のポリカー
ボネート基板と張り合わせ、温度70℃、湿度85％
の条件で350時間の加速試験を行ないその前後の
ドロツプインエラーレートを測定したところ劣化
は全く見られなかつた。 In addition, this disk was attached to another polycarbonate substrate using adhesive, and the temperature was 70℃ and the humidity was 85%.
When we conducted an accelerated test for 350 hours under these conditions and measured the drop-in error rate before and after the test, no deterioration was observed at all.
比較例１，２
実施例１と同様にTbFeCo層までほ作製し、次
にAl又はTa膜からなる反射層を300Å形成した。
実施例１と同一の条件にて記録感度、及びキヤリ
ア・レベルを測定した。結果を第１図に示した。
第１図に示すようにAl中のTa含有率の増加に伴
ない最適記録パワー及びキヤリア・レベルは減少
するがTaの含有率が低い場合はキヤリア・レベ
ルをほとんど減少させずに最適記録パワーを大き
く下げることができる。Comparative Examples 1 and 2 In the same manner as in Example 1, up to the TbFeCo layer was fabricated, and then a reflective layer made of Al or Ta film was formed to a thickness of 300 Å.
Recording sensitivity and carrier level were measured under the same conditions as in Example 1. The results are shown in Figure 1.
As shown in Figure 1, as the Ta content in Al increases, the optimal recording power and carrier level decrease, but when the Ta content is low, the optimal recording power can be maintained with almost no decrease in the carrier level. It can be lowered significantly.
本発明の光磁気記録媒体は再生信号品質及び記
録感度に優れる。
The magneto-optical recording medium of the present invention has excellent reproduction signal quality and recording sensitivity.
第１図は反射膜中のTa含有率と最適記録パワ
ー及びキヤリア・レベルとの関係を示すものであ
る。
FIG. 1 shows the relationship between the Ta content in the reflective film and the optimum recording power and carrier level.
Claims (1)
を順次設けてなる光磁気記録媒体において、反射
層をTaを0.1〜15at％含有するAl合金によつて形
成したことを特徴とする光磁気記録媒体。1. A magneto-optical recording medium comprising an interference layer, a magneto-optical recording layer and a reflective layer sequentially provided on a substrate, characterized in that the reflective layer is made of an Al alloy containing 0.1 to 15 at% Ta. recoding media.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62158918A JPS644938A (en) | 1987-06-26 | 1987-06-26 | Magneto-optical recording medium |
| CA000570235A CA1324213C (en) | 1987-06-26 | 1988-06-23 | Magnetooptical recording media |
| EP88305842A EP0296888B1 (en) | 1987-06-26 | 1988-06-24 | Magnetooptical recording media |
| DE88305842T DE3883310T2 (en) | 1987-06-26 | 1988-06-24 | Magneto-optical media. |
| KR1019880007767A KR960010928B1 (en) | 1987-06-26 | 1988-06-24 | Magneto-optical recording media |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62158918A JPS644938A (en) | 1987-06-26 | 1987-06-26 | Magneto-optical recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS644938A JPS644938A (en) | 1989-01-10 |
| JPH0524572B2 true JPH0524572B2 (en) | 1993-04-08 |
Family
ID=15682186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62158918A Granted JPS644938A (en) | 1987-06-26 | 1987-06-26 | Magneto-optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS644938A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02223040A (en) * | 1988-11-04 | 1990-09-05 | Fuji Photo Film Co Ltd | Magneto-optical recording medium |
| JPH02226531A (en) * | 1989-02-27 | 1990-09-10 | Hitachi Ltd | Structure of optical disk |
| JP2779521B2 (en) * | 1989-06-26 | 1998-07-23 | 富士写真フイルム株式会社 | Magneto-optical recording medium |
| JP2654689B2 (en) * | 1989-05-16 | 1997-09-17 | 富士写真フイルム株式会社 | Magneto-optical recording medium |
| JPH0718003B2 (en) * | 1990-01-11 | 1995-03-01 | 株式会社神戸製鋼所 | Sputtering target for optical media Ingot material |
| US5500301A (en) | 1991-03-07 | 1996-03-19 | Kabushiki Kaisha Kobe Seiko Sho | A1 alloy films and melting A1 alloy sputtering targets for depositing A1 alloy films |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6157053A (en) * | 1984-08-28 | 1986-03-22 | Canon Inc | Optical recording medium |
-
1987
- 1987-06-26 JP JP62158918A patent/JPS644938A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6157053A (en) * | 1984-08-28 | 1986-03-22 | Canon Inc | Optical recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS644938A (en) | 1989-01-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |