JPS58199456A - Optical thermomagnetic recording medium - Google Patents
Optical thermomagnetic recording mediumInfo
- Publication number
- JPS58199456A JPS58199456A JP8265382A JP8265382A JPS58199456A JP S58199456 A JPS58199456 A JP S58199456A JP 8265382 A JP8265382 A JP 8265382A JP 8265382 A JP8265382 A JP 8265382A JP S58199456 A JPS58199456 A JP S58199456A
- Authority
- JP
- Japan
- Prior art keywords
- recording medium
- film
- photothermal
- magnetic recording
- 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.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F10/00—Thin magnetic films, e.g. of one-domain structure
- H01F10/08—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers
- H01F10/10—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition
- H01F10/12—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition being metals or alloys
- H01F10/13—Amorphous metallic alloys, e.g. glassy metals
- H01F10/133—Amorphous metallic alloys, e.g. glassy metals containing rare earth metals
- H01F10/135—Amorphous metallic alloys, e.g. glassy metals containing rare earth metals containing transition metals
- H01F10/137—Amorphous metallic alloys, e.g. glassy metals containing rare earth metals containing transition metals containing cobalt
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10582—Record carriers characterised by the selection of the material or by the structure or form
- G11B11/10586—Record carriers characterised by the selection of the material or by the structure or form characterised by the selection of the material
- G11B11/10589—Details
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- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、光磁気メモリー、磁気記鎌、表示素子などに
用いられ、磁気カー効果あるいは７アラデー効果などの
磁気光学効果を用いて読み出すことのできる光熱磁気記
録媒体に関するもので、特に、耐腐食性を向上させた磁
性薄膜記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magneto-optical recording medium that can be used for magneto-optical memories, magnetic recording devices, display elements, etc., and that can be read using magneto-optic effects such as the magnetic Kerr effect or the Alladay effect. In particular, it relates to a magnetic thin film recording medium with improved corrosion resistance.
従来、光熱磁気記録媒体としてはＭｎＢｔ、 Ｍｎ０ｕ
Ｂ１等の多結晶薄膜、Ｇａ０ｏ、 （ｙＬＦ＊、 Ｔｂ
Ｆｅ、 ＤｙＦｓ、’ ＧａＴｂＦｅ。Conventionally, MnBt, Mn0u are used as photothermal magnetic recording media.
Polycrystalline thin film such as B1, Ga0o, (yLF*, Tb
Fe, DyFs, 'GaTbFe.
ＴｂＤｙＦ−等の非晶質薄膜、ＧａＩＧ等の単結晶薄膜
等が知られている。Amorphous thin films such as TbDyF-, single crystal thin films such as GaIG, etc. are known.
この等の薄膜のうち、大面積の薄膜を室温近傍の温度で
製作す□る製膜性、信号を小さな光熱エネルギーで書き
込むための書き込み効率、書き込まれた信号をＳ／Ｎ比
よく読み出すための読み出し効率等を勘案し、最近では
前記非晶質薄膜が光熱磁気記録媒体として優れていると
考えられている。Among these thin films, there are several factors that are important, including film-forming properties that allow large-area thin films to be fabricated at temperatures close to room temperature, writing efficiency that allows signals to be written with small photothermal energy, and readout of written signals with a good S/N ratio. Considering read efficiency and the like, the amorphous thin film is recently considered to be excellent as a photothermal magnetic recording medium.
特に、ＧａＴｂＦ・は、カー回転角も大きく、１５［１
℃前後のキ二−リ一点を持つから光熱磁気記録媒体とし
ては最適である。更に我々は、カー回転角を向上させる
目的で研究した結果、ＧａＴｂＦ・Ｃｏがカー回転角が
充分に大きく、Ｓ／Ｎ比の良い読み出しが可能な光熱磁
気記録媒体であることを見い出した。In particular, GaTbF has a large Kerr rotation angle of 15[1
Since it has a single key point around ℃, it is most suitable as a photothermal magnetic recording medium. Furthermore, as a result of our research aimed at improving the Kerr rotation angle, we found that GaTbF.Co is a photothermal magnetic recording medium that has a sufficiently large Kerr rotation angle and allows readout with a good S/N ratio.
然しなから、ＧａＴｂＦｅあるいはＧａＴｂＦｅ（３ｏ
をはじめとして、その他の非晶質磁性体の特徴として、
耐腐食性が悪い事があげられる。即ち、大気、水蒸気に
触れると、磁気特性が低下するだけでなく、最終的には
完全に酸化して透明化してしまう。However, GaTbFe or GaTbFe(3o
In addition, other characteristics of amorphous magnetic materials include:
One of the problems is that it has poor corrosion resistance. That is, when it comes into contact with air or water vapor, it not only deteriorates its magnetic properties but also eventually becomes completely oxidized and becomes transparent.
その為に、従来から記録層の上に保護層を設けたυ、更
に不活性ガスによシ封じ込めたデ碕ス□り状記録媒体が
提案されている。To this end, a disk-shaped recording medium has been proposed in which a protective layer is provided on the recording layer, and a disk-shaped recording medium is further sealed with an inert gas.
本発明の目的は、従来とは異なシ記録媒体自身に耐腐食
性を持たせようとするもので、磁気特性を損ねることな
く耐腐食性を向上させた非晶質の光熱磁気記録媒体を提
供することにある。The purpose of the present invention is to provide a non-conventional recording medium with corrosion resistance, and to provide an amorphous photothermal magnetic recording medium with improved corrosion resistance without impairing magnetic properties. It's about doing.
本発明に係る光熱磁気記録媒体においては、膜面に垂直
方向に磁化容易軸を有する非晶質磁性合金、例えばＧａ
ＴｂＦｓ、 ＧａＴｂＦｅＯｏに、Ｏｒを添加すること
によシ上記目的を達成せんとするものである。In the photothermal magnetic recording medium according to the present invention, an amorphous magnetic alloy having an axis of easy magnetization perpendicular to the film surface, such as Ga
The above object is attempted to be achieved by adding Or to TbFs and GaTbFeOo.
更に、本発明に係る光熱磁気記録媒体においては、磁気
特性を損わないためには、Ｏｒが原子比で０．１ ａｔ
ｏｍ％〜５ Ｑ ａｔｏｍ ％の範囲に存在することが
望ましい。以下、本発明を実施例によって詳細に説明す
る。Furthermore, in the photothermal magnetic recording medium according to the present invention, in order not to impair the magnetic properties, Or should have an atomic ratio of 0.1 at.
It is desirable that it exists in the range of om% to 5 Q atom%. Hereinafter, the present invention will be explained in detail with reference to Examples.
実施例１１高周波スパッタ装置において、６インチ角の
白板ガラスを基板とし、第１のターゲットとして４イン
チφのＦ・上に、５市角のＧａ、 Ｔ′ｂ片を均一に並
べたものと、第２のターゲットとして４インチφのＯｒ
を使用した。チャンバー内を１．５Ｘ １’０”””Ｐ
ａ以下になるまで真空排気した後、Ａｒガスを４×１０
″″Ｐ＆まで導入し、真空排気系のメインバルブを操作
することによ、９、Ａｒ圧を５Ｐ＆にした。Example 11 In a high-frequency sputtering apparatus, a 6-inch square white glass plate was used as a substrate, and 5 square pieces of Ga and T'b were uniformly arranged on a 4-inch diameter F as a first target. 4 inch φ Or as the second target
It was used. Inside the chamber 1.5X 1'0"""P
After evacuation until the temperature is below a, Ar gas is evacuated to 4×10
9. Ar pressure was brought to 5P& by operating the main valve of the vacuum exhaust system.
高周波電源よシ第１のターゲットはスパッタ電力２５０
Ｗと一定とし、第２のターゲットはスパッタ電力を変え
た２源同時スパッタによシ下記の種々の組成の０４Ｔｂ
ＦｓＣｒ膜を作製した。The first target uses a high frequency power source with a sputtering power of 250
The second target was 04Tb with various compositions as shown below.
An FsCr film was produced.
（（Ｇ４ｏ、ｉ Ｔｂａ、ｓ）ｏ、＋ｕ Ｆｅａ、ｙ
ｓ ）ｏ、ａｍ Ｃｒｏ、ａｓ（（Ｇａａ、ａ Ｔｂ
ｏ、ｓ）ａ、ｓｚ Ｆｅｅ、ｗｅ ）ｏ、＊ Ｏｒｏ、
ｚ（（Ｇ４ｏ、ｓ Ｔｂｏ、ｉ）ｏ、ａ１ｙ＠（１，
’Ｆ＃ ） ６．ｊｌ Ｏｒｏ、ａｍ（（Ｇ（ｌｏ、
ａ Ｔｂｏ、ｓ）ｏ、ｓｚ ｙ＠０．’ｙｌ ）ｏ、ｓ
Ｏｒｅ、ｓ又、上記第１′のターゲットのＦ・の上に
、５ｆｆＩＩｎ角のＣｒ片を小さく切った小片とを均一
にならべ、上述した過程によシ下記の組成なＧａＴｂＦ
ｅＣｒ膜を作成した。 １゜
（（Ｇ４ｏ＋ｓ Ｔｂｏ、ｉ）ｏ、ｓｚ Ｉ’＠＠、ｆ
ｆ＠ ）ｏ、ｅ＊ｙ Ｃｒｏ、Ｏｏｗ（ＣＧ＋１ｇ１
．Ｉ Ｔｂｏ、ｉ）ｏ、ｓ、Ｆ１ａ、ｎ ）０．１゜（
３ｒｏ、ｏｘ上記構成のＧａＴｂＦｅＯｒを５５℃９０
襲の恒温恒湿槽に入れて、耐腐食試験を試みた結果を第
１図に示す。第１図は縦軸に単位重量当シの重量増加分
、横軸に日数、即ち時間を取ったもので、重量が増加す
ればする程腐食度が進んだことを示している。((G4o,i Tba,s)o,+u Fea,y
s )o, am Cro, as((Gaa, a Tb
o, s) a, sz Fee, we) o, * Oro,
z((G4o, s Tbo, i)o, a1y@(1,
'F#) 6. jl Oro, am((G(lo,
a Tbo, s) o, sz y@0. 'yl) o, s
Also, on top of the first target F, a small piece of 5ffIIn square Cr piece cut into small pieces was uniformly arranged, and by the above process, a GaTbF with the following composition was formed.
An eCr film was created. 1゜((G4o+s Tbo, i) o, sz I'@@, f
f@)o, e*y Cro, Oow (CG+1g1
．． I Tbo,i)o,s,F1a,n)0.1゜(
3ro, ox GaTbFeOr with the above configuration at 55℃90
Figure 1 shows the results of a corrosion resistance test carried out in a constant temperature and humidity chamber. In FIG. 1, the vertical axis shows the increase in weight per unit weight, and the horizontal axis shows the number of days, that is, time, and the more the weight increases, the more the degree of corrosion progresses.
Ｏｒの入っていないＧａＴｂＦ・膜は、２〜５日で表面
の腐食（酸化）が認められたが、Ｇ４ＴｂＦｅＧｒ膜は
Ｏｒの量が多くなるにつれて、重量変化分、即ち酸化の
度合が小さく、耐腐食性が向上した事がわかった。In the GaTbF film without Or, corrosion (oxidation) on the surface was observed within 2 to 5 days, but as the amount of Or increases, the weight change, that is, the degree of oxidation, decreases in the G4TbFeGr film, and the resistance increases. It was found that the corrosivity was improved.
また、磁気特性（保持力）も変化はなかった。Furthermore, there was no change in magnetic properties (coercive force).
尚、上記したＧａＴｂＦ・Ｃｒ膜では、Ｏｒが原子比で
６０％以上入った膜は、膜面に垂直方向に磁化容易軸を
有しない磁性膜であった。In the GaTbF.Cr film described above, the film containing 60% or more of Or in an atomic ratio was a magnetic film that did not have an axis of easy magnetization in the direction perpendicular to the film surface.
実施例２Ｉ高周波スパッター装置において、５インチ角
の白板ガラスを、基板とし、第１のターゲラＦとして４
インチφのＦｅ上に５１１ＩＩ角のＧａ、 Ｔｂ、Ｃ。Example 2I In a high-frequency sputtering apparatus, a 5-inch square white plate glass was used as the substrate, and 4
511II square Ga, Tb, C on inch φ Fe.
並
片を均一に廊ぺたものと第２のターゲットとして４イン
チφのＯｒを使用、又は第１のターゲットのＦｅの上に
５ｍｍ角の（ｒａ、 Ｔｂ、 Ｏｅ片と、５ｍｍ角のＣ
ｒ片を小さく切った小片とを均一にならべる事によシ、
上記第１実施例と同様のプロセスで王妃°の組成の（ｒ
ｌＴｂＦ＊ｏｏｃｒ膜を作成した。A 4-inch φ Or is used as a second target with parallel pieces evenly spaced, or a 5 mm square (ra, Tb, Oe piece and a 5 mm square C
By evenly arranging the r piece and the small pieces cut into small pieces,
The composition of the queen ° (r
An lTbF*oocr film was created.
（（Ｇ４ｏ、ｉ Ｔｂｏ＋ｓ）ｏ、５ｘ（Ｆ・ｏ、ｔ
Ｃｏｏ、ｚ）ｏ、ｖｓ）ｏ７ｓ ｃｒｏ、０Ｘ（（Ｇ
４ｏ、ｉ Ｔｂ６．１）０．１１ （Ｆｅ６．＠ Ｃｏ
ｏ、Ｎｏ、ヤリｏ０ｍｅｑ Ｃｒ６．ｏｏｇ（（Ｇ＋ｌ
Ｏ，５Ｔｂｏ、ｓ）ｏ、５ｚ（Ｆ１ａ、ｅＣｏｏ、ｚ）
ａ、ｖ−）ａ、＊ａ Ｏｒｏ、ａｍ（Ｇ４ＴｂＦｅＧｏ
）ｏ、ｓ Ｏｒｏ、ｚ（ＧｉｌＴｂＦ＠０ｏ）６．１ｇ
Ｃｒ６，１ｍ（ＧｓｌＴｂＦ＠Ｇｏ） ６．６ Ｏｒ
（＠上記ＧａＴｂＦ＠０ｏＧｒｊｉでは、Ｏｒが３０
ａｔｏｍ％以上入った膜は、膜面に垂直方向に磁化容易
軸を有さない磁性膜であった。((G4o,i Tbo+s)o,5x(F・o,t
Coo, z) o, vs) o7s cro, 0X ((G
4o,i Tb6.1)0.11 (Fe6.@Co
o, No, Yari o0meq Cr6. oog((G+l
O,5Tbo,s)o,5z(F1a,eCoo,z)
a, v-) a, *a Oro, am (G4TbFeGo
) o, s Oro, z (GilTbF@0o) 6.1g
Cr6,1m (GslTbF@Go) 6.6 Or
(@In the above GaTbF@0oGrji, Or is 30
The film containing atomic % or more was a magnetic film that did not have an axis of easy magnetization in the direction perpendicular to the film surface.
上記）ＧａＴｂＦｅ０ｏＯｒ膜とＧａＴｂＦｅＣｏ展を
実施例１と同様な耐腐食性試験を試みた結果、Ｇ４Ｔｂ
Ｆ＠Ｇｏ膜は４〜５日で表面の腐食が見られたが、Ｇａ
ＴｂＦ・０ｏＣｒ膜は、第１図と同様な傾向を示し、Ｃ
ｒ量が多くなるにつれて耐腐食性が向上した。As a result of trying the same corrosion resistance test as in Example 1 on the above) GaTbFe0oOr film and GaTbFeCo film, G4Tb
The surface of the F@Go film showed corrosion after 4 to 5 days, but the Ga
The TbF・0oCr film showed the same tendency as shown in Fig. 1, and the C
Corrosion resistance improved as the amount of r increased.
本発明に係る光熱磁気記録媒体を、ガラス、金属、プラ
スチック等の基板に□スパッター真空蒸着法等で積層す
るに際し、該記録媒体上に周知の保護層、或いは保護層
を兼ねた反射防止層や断熱層等を設ければ、更に耐腐食
性は向上する。又、従来知られている様な、不活性ガス
を閉じ込めたエアーサンドウィッチ型構成にしても、耐
腐食性が向上することは言うまでもない。When the photothermal magnetic recording medium according to the present invention is laminated on a substrate made of glass, metal, plastic, etc. by sputter vacuum evaporation method or the like, a well-known protective layer or an antireflection layer that also serves as a protective layer is applied on the recording medium. Corrosion resistance can be further improved by providing a heat insulating layer or the like. Furthermore, it goes without saying that the corrosion resistance can be improved even if the conventionally known air sandwich type structure in which an inert gas is confined is used.
更に、本発明に係る光熱磁気記録媒体では、非晶質磁性
体にＳｉとＯｒを同時に添加したもの、或いはＯｒと共
にＡＪ等の他の元素を添化しても腐食性に優れた磁性膜
が得られる。Furthermore, in the photothermal magnetic recording medium according to the present invention, a magnetic film with excellent corrosion resistance can be obtained even when Si and Or are added simultaneously to the amorphous magnetic material, or when other elements such as AJ are added together with Or. It will be done.
以上、本発明に係る光熱磁気記録媒体においては、非晶
質磁性膜、例えばＧａＴｂＦｅ膜、 ＧａＴｂＦｅ膜ｏ
膜等にｃｒを添加することによシ、従来より耐腐食性を
向上せしめた磁性膜を得たものであシ、簡易な手段によ
り優れた効果を得たものである。As described above, in the photothermal magnetic recording medium according to the present invention, an amorphous magnetic film, for example, a GaTbFe film, a GaTbFe film, or
By adding Cr to the film, etc., a magnetic film with improved corrosion resistance than before was obtained, and excellent effects were obtained by simple means.
第１図は、本発明に係る光熱磁気記録媒体の一実施例で
あるＧａＴｂＦ・Ｏｒの耐腐食試験の結果を示す図。
８／馴
鴫ｌ寺日数FIG. 1 is a diagram showing the results of a corrosion resistance test of GaTbF.Or, which is an example of a photothermal magnetic recording medium according to the present invention. 8/Number of temple days
Claims (1)
合金にＯｒを添加した事を特徴とする光熱磁気記録媒体
。 （２）前記Ｏｒの原子比がＱ、ｌ ａｔｏｍ％〜５０
ａｔｏｍ ％の範囲に有する特許請求の範囲第１項記載
の光熱磁気記録媒体。 （６）前記非晶質磁性合金は、ＧａＴｂＦｅあるいはＧ
４ＴｂＦｅＣｏである特許請求の範囲第１項記載の光熱
磁気記録媒体。[Scope of Claims] (1) A photothermal magnetic recording medium characterized in that Or is added to an amorphous magnetic alloy having an axis of easy magnetization perpendicular to the film surface. (2) The atomic ratio of Or is Q, l atom% ~ 50
The photothermal magnetic recording medium according to claim 1, wherein the photothermal magnetic recording medium has a content in the range of atom %. (6) The amorphous magnetic alloy is GaTbFe or G
The photothermal magnetic recording medium according to claim 1, which is 4TbFeCo.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8265382A JPS58199456A (en) | 1982-05-17 | 1982-05-17 | Optical thermomagnetic recording medium |
| US06/671,978 US4693943A (en) | 1982-05-10 | 1984-11-16 | Magnetooptical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8265382A JPS58199456A (en) | 1982-05-17 | 1982-05-17 | Optical thermomagnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58199456A true JPS58199456A (en) | 1983-11-19 |
| JPH0410132B2 JPH0410132B2 (en) | 1992-02-24 |
Family
ID=13780382
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8265382A Granted JPS58199456A (en) | 1982-05-10 | 1982-05-17 | Optical thermomagnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58199456A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5996714A (en) * | 1982-11-26 | 1984-06-04 | Ricoh Co Ltd | Magnetic recording medium |
| JPS60251540A (en) * | 1984-05-26 | 1985-12-12 | Ricoh Co Ltd | Amorphous magnetooptic layer |
| US5273836A (en) * | 1987-04-14 | 1993-12-28 | Yamaha Corporation | Magnetooptic recording material |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56126907A (en) * | 1980-03-12 | 1981-10-05 | Kokusai Denshin Denwa Co Ltd <Kdd> | Magnetic optical recording medium |
-
1982
- 1982-05-17 JP JP8265382A patent/JPS58199456A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56126907A (en) * | 1980-03-12 | 1981-10-05 | Kokusai Denshin Denwa Co Ltd <Kdd> | Magnetic optical recording medium |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5996714A (en) * | 1982-11-26 | 1984-06-04 | Ricoh Co Ltd | Magnetic recording medium |
| JPH0430166B2 (en) * | 1982-11-26 | 1992-05-21 | ||
| JPS60251540A (en) * | 1984-05-26 | 1985-12-12 | Ricoh Co Ltd | Amorphous magnetooptic layer |
| US5273836A (en) * | 1987-04-14 | 1993-12-28 | Yamaha Corporation | Magnetooptic recording material |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0410132B2 (en) | 1992-02-24 |
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