JPS60253041A - Photothermomagnetic recording medium - Google Patents
Photothermomagnetic recording mediumInfo
- Publication number
- JPS60253041A JPS60253041A JP10908584A JP10908584A JPS60253041A JP S60253041 A JPS60253041 A JP S60253041A JP 10908584 A JP10908584 A JP 10908584A JP 10908584 A JP10908584 A JP 10908584A JP S60253041 A JPS60253041 A JP S60253041A
- Authority
- JP
- Japan
- Prior art keywords
- film
- coercive force
- magneto
- rotation angle
- kerr rotation
- 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
Classifications
-
- 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
-
- 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
Landscapes
- Thin Magnetic Films (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
この発明は、光磁気メモリ、磁気転写１表示素子等に用
いられるもので、高精度の読み出しを可能とした光熱磁
気記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a magneto-optical recording medium that is used in magneto-optical memories, magnetic transfer single display elements, etc., and which enables highly accurate reading.
光磁気メモリは保磁力（Ｈｅ）の大きな垂直磁化膜の特
定の微小部分をレーザ光などで局部的に加熱して磁気反
転を起させ、そこに情報を付与した磁性メモリで、情報
の読み出しく再生）Ｉこは磁気光学カー（Ｋｅｒｒ）効
果またはファラデイー（Ｆ ａｒａｄａｙ）効果による
光の偏光面の回転の有無を検ｊ」ルすることで行われる
。読み出しに磁気光学カー効果を使うかファラデイー効
果を使うかは記録媒体の種類とシステム構成によって決
まるが、現在考えられているシステムでは磁気光学カー
効果を利用するものが多い。Magneto-optical memory is a magnetic memory in which information is added by locally heating a specific minute part of a perpendicularly magnetized film with a large coercive force (He) using a laser beam, etc., to cause magnetic reversal. Reproduction) This is performed by checking for the presence or absence of rotation of the plane of polarization of light due to the magneto-optical Kerr effect or Faraday effect. Whether to use the magneto-optical Kerr effect or the Faraday effect for reading depends on the type of recording medium and system configuration, but many of the systems currently being considered utilize the magneto-optic Kerr effect.
光熱磁気記録媒体としては次のような特性が要求される
。A photothermal magnetic recording medium is required to have the following characteristics.
■保磁力Ｈｃの大きな垂直磁化膜であること、■磁気光
学カー回転角またはファラデイー回転角が大きく、かつ
、反射−３４が高いこと、■キュリ一温度または磁気補
償温度が適当な値であること、■記録ビットｌｈが小さ
く、マージンが広く、安定であること、■化学的に安定
であること、■組成一方光熱磁気記録材料としては、現
在まゼにＭ ｎ Ｂ ｉ 、 Ｍ ｎ Ｃｕ Ｂ ｉ
、 Ｍ ｎ Ａ Ｉ Ｇ ｅ 、 Ｍ ｎＧａＧｅ、ｍ
土類磁性ガーネット系Ｌ ｐ Ｅ ＩＱ 、”１ｆ３−
土類遷移金属（Ｒ−Ｔ）系非晶質合金膜なとが研究され
ている。■It must be a perpendicularly magnetized film with a large coercive force Hc; ■It must have a large magneto-optical Kerr rotation angle or Faraday rotation angle and a high reflection -34; ■It must have an appropriate Curie temperature or magnetic compensation temperature. , ■ The recording bit lh is small, the margin is wide, and it is stable. ■ It is chemically stable. ■ The composition On the other hand, as a photothermal magnetic recording material, currently M n B i , M n Cu B i
, MnAIGe, MnGaGe, m
Earth magnetic garnet type L p E IQ, “1f3-
Earth-transition metal (RT)-based amorphous alloy films are being studied.
以上のように、光熱磁気記録材料にはそれぞれ長所と短
所とかあるか、中でも共通している短所は磁気光学カー
回転角なとの磁気光効果が小さいことである。As described above, each photothermal magnetic recording material has its own advantages and disadvantages, and the common disadvantage is that the magneto-optical effect, such as the magneto-optic Kerr rotation angle, is small.
とりわけ、冷土類遷移金属（Ｒ−Ｔ）系非晶質合金膜は
前記の記録媒体としての要件をかなり満たしており、注
目されているか、磁気光学カー回転角か小さく、そのた
め読み出しのＳ／Ｎかわるいことが応用−＼の最も大き
な障壁となっている。In particular, cold earth transition metal (R-T) based amorphous alloy films meet the above-mentioned requirements as recording media and are attracting attention, and their magneto-optical Kerr rotation angle is small, which makes it difficult to read S/ N change is the biggest barrier to application.
本来磁性体の磁気光学カー回転角θイはその物質の電子
構造に由来するもので固有の物理量であり、そのため波
長によって変化する。また、この効果は光の反射に対す
るものであるので、当然醇化やよごれなとの表面状態に
著しく依存することか知られている。Originally, the magneto-optical Kerr rotation angle θi of a magnetic material is derived from the electronic structure of the material and is a unique physical quantity, so it changes depending on the wavelength. Furthermore, since this effect is related to the reflection of light, it is known that it depends significantly on the surface condition, such as mellowing or dirtiness.
したがって、磁気光学カー回転角θ３を増大ぎせるには
、物質の電子構造を変えるがまたは光の干渉なとを利用
して増大させるかなとしかないか、前渚の方法には新物
質を見つけることが必要であり、また、後者の方法も既
にいくつかの提案かなされている。Therefore, the only way to increase the magneto-optical Kerr rotation angle θ3 is to change the electronic structure of the material or use optical interference to increase it. Maenagi's method involves finding new materials. This is necessary, and some proposals have already been made for the latter method.
この発明は、上記の点にかんかみなされたちので、垂直
磁気異方性を有し、保磁力が高く、しがも磁気光学カー
回転角もしくは反射率の高い光熱磁気記録媒体を提供す
ることを目的としたものである。以下、この発明番コつ
いて説明する。In view of the above points, the present invention aims to provide a photothermal magnetic recording medium having perpendicular magnetic anisotropy, high coercive force, and high magneto-optical Kerr rotation angle or reflectance. This is the purpose. This invention number will be explained below.
この発明に係る光熱磁気記録媒体の１つは、面上類金属
であるカドリニュウム（Ｇｄ）、テルビウム（Ｔｂ）、
ディスプロシウム（Ｄｙ）と鉄（Ｆ ｅ）とコバルト（
Ｃｏ）からなる垂直磁気異方性を廂する非晶質磁性合金
薄膜で、次に示す組成範囲のものである。One of the photothermal magnetic recording media according to the present invention includes cadrinium (Gd), terbium (Tb), which are planar metals,
Dysprosium (Dy), iron (Fe), and cobalt (
This is an amorphous magnetic alloy thin film consisting of Co) exhibiting perpendicular magnetic anisotropy and having a composition range shown below.
Ｇｄａ Ｔｂｂ Ｄ ｙｃ ＣＯｘ Ｆ ｅｙ −−（
１）ここで、Ｏｖａ≦１５ 原子％
ｏ＜ｂ≦１５ 原子％
０＜ｃ≦１５Ｉｊｉ！子％
０＜ｘ＜４５ 原子％
４５＜ Ｙ ＜ ８５ 原子％
上記第（１）式の材料を用いた媒体では、現在一番大き
な磁気光学カー回転角（０、）を示すＣｄ−Ｔｂ−Ｃｏ
−Ｆｅ系垂直磁化膜の磁気光学力〜回転角θにより１〜
２分（表面被覆なしの膜面において）たけ磁気光学カー
回転角ＯＫの高いものか得られる（保磁力Ｈｃはほぼ同
一値を示す）。Gda Tbb Dyc COx F ey --(
1) Here, Ova≦15 atomic% o<b≦15 atomic% 0<c≦15Iji! 0<x<45 atomic% 45<Y<85 atomic% In the medium using the material of the above formula (1), Cd-Tb-Co exhibits the largest magneto-optical Kerr rotation angle (0,
-Magneto-optical force of Fe-based perpendicularly magnetized film ~1~ depending on rotation angle θ
2 minutes (on the film surface without surface coating), a magneto-optical Kerr rotation angle as high as 0.25 mm can be obtained (the coercive force Hc shows almost the same value).
本来、Ｄｙは単原子異方性の大きな磁性元素で合金状態
ではその磁気モーメントか円錐状に分布しやすく、磁気
光学カー回転角０２も大きくないものと占えられている
金属であるか、第（１）式のような合金にすることによ
り、磁気光学カー回転角θつの明らかな増大効果か見出
されたものである。これは軌道角運動量が大きく磁気Ｗ
方性の強い原子を含んだ合金の電子構造の変化に由来す
るものと考えられるか、まだ詳しいことはわからない。Originally, Dy is a magnetic element with large monatomic anisotropy, and in an alloy state, its magnetic moment tends to be distributed conically, and the magneto-optical Kerr rotation angle 02 is assumed to be not large. It has been found that by forming an alloy as shown in formula 1), there is a clear effect of increasing the magneto-optical Kerr rotation angle θ. This has a large orbital angular momentum and magnetic W
Whether this is thought to be due to a change in the electronic structure of the alloy containing strongly oriented atoms, the details are not yet known.
しかじ、傾向としてはＤｙのような性質の元４、を多ノ
しにすると磁気光学カー回転角０にか増大するのでネオ
ジミウムＮｄ、プラン′セオジミウムＰｒやサマｌ；ウ
ムＳｍなとを依＠衿加することで磁気光学カー回転角Ｏ
うをさらに増大させらねる可能性かある。However, as a tendency, when element 4 with properties such as Dy is increased, the magneto-optical Kerr rotation angle increases to 0, so it depends on neodymium Nd, plan'theodymium Pr and sum Sm. By adding the collar, the magneto-optical car rotation angle O
There is a possibility that this could lead to further increase.
ｌ欠しこ、この発明の他の実施例である光熱磁気記録媒
体は、為土類金属（Ｒ：Ｇｄ、Ｔｂ、Ｄｙ。However, a photothermal magnetic recording medium according to another embodiment of the present invention is made of earth metals (R: Gd, Tb, Dy.
Ｈｏ、Ｅｒ、Ｓｍ、Ｐｒおよびこれらの複合物、以下同
様）、遷移金属（Ｔ： Ｆｅ 、Ｃｏ 、Ｎｉおよびこ
れらの複合物、以下同様）および他の金属元素（Ｍ：Ａ
ｇ、Ｍｇ、Ｃｕ、Ｂ、Ｇａおよびこれらの複合物、以下
同様）から成る非晶質磁性薄膜で、膜面に対し垂直方向
に磁化を向けるのに充分な垂直磁気異方性Ｋｕと高い保
磁力Ｈｅおよび磁気光学カー回転角θＫ （もしく１オ
高い反射率Ｒｅ）を示すことを特徴とした全く新規な媒
体材料である。この材料は前記Ｒ−Ｔ合金に対して、Ｍ
（Ａｇ、Ｍｇ、Ｃｕ、Ｂ、Ｇａ）（７）量ＸがｏくＸ≦
１５原子％だけ含まれている必要があり、ベースの＋Ｒ
−Ｔ＋系非晶質合金よりも保礒−力−Ｈｃと磁気光学カ
ー回転角θ、の値を増大ｙしことができる。Ho, Er, Sm, Pr and their composites, hereinafter the same), transition metals (T: Fe, Co, Ni and these composites, hereinafter the same) and other metal elements (M:A
It is an amorphous magnetic thin film consisting of amorphous materials such as G, Mg, Cu, B, Ga, and their composites (hereinafter the same shall apply), and has perpendicular magnetic anisotropy Ku sufficient to orient magnetization perpendicular to the film surface and high retention. It is a completely new medium material characterized by exhibiting a magnetic force He and a magneto-optic Kerr rotation angle θK (or a reflectance Re that is 100% higher). This material is M
(Ag, Mg, Cu, B, Ga) (7) Quantity
It must contain only 15 atom%, +R of the base
-The values of the retention force -Hc and the magneto-optic Kerr rotation angle θ can be increased compared to the T+ type amorphous alloy.
一般に、保磁力Ｈｅは記録ビットの安定性に、関係があ
り、勿論大きいことか必要である。この発明の材料を用
いると、ベースに用いたＲ−Ｔ合金よりも保磁力Ｈｅを
大きくすることができるので、保磁力Ｈｅを同じ値にす
る時には保磁力Ｈｃを大きい分だけ遷移金属を多くする
ことができるため、磁気光学カー回転角θ、をより増大
させることができ、Ｓ／Ｎを大幅１こ改善することが可
能である。また、この発明の材料のうち、銀（Ａｇ）と
銅（Ｃｕ）を含む媒体の反射率Ｒｅは、添加しないもの
よりも０〜５％程度良くなるので、Ｓ／Ｎの改善のため
にはさらによい結果が得られる。Generally, the coercive force He is related to the stability of recording bits, and of course it is necessary to have a large coercive force He. By using the material of this invention, the coercive force He can be made larger than that of the RT alloy used as the base, so when the coercive force He is kept at the same value, the amount of transition metal is increased by the amount that increases the coercive force Hc. Therefore, it is possible to further increase the magneto-optic Kerr rotation angle θ, and it is possible to significantly improve the S/N by 1. Furthermore, among the materials of this invention, the reflectance Re of the medium containing silver (Ag) and copper (Cu) is about 0 to 5% better than that of the medium without additives, so it is necessary to improve the S/N. Even better results are obtained.
（Ｒ−Ｔ）系非晶質合金膜の磁気光学カー回転角θ８を
増大させることはこれまでにもいくつかなされてきた。Several attempts have been made to increase the magneto-optic Kerr rotation angle θ8 of (RT)-based amorphous alloy films.
単純な二元系の他に、ＧｄＤｙＦｅ 、ＧｄＴｂＦｅ
、ＴｂＦｅＣｏなどの三元系、ＧｄＴｂＣ。In addition to simple binary systems, GdDyFe, GdTbFe
, ternary systems such as TbFeCo, GdTbC.
Ｆｅなどの四元系、その他非磁性金属元素を含む系とし
てはＧｄＦｅＳｎ、ＧｄＦｅＢ１などがこれまてに見つ
けられた。しかし、これらの中で明らかに効果かあるの
は、磁性元素である希土類元素Ｒと遷移元素Ｔを相互に
多重にした系であり、現在のところ、一番磁気光学カー
回転角θにの大きな系はＧｄＴｂＣｏＦｅの四元系であ
る。非磁性元素を添加した系については、まだ例が少な
いいる。しかし、これについては、後述するように、追
試の結果、明らがな効果がみられなが一４立−ことなど
から疑問視する向きのあるところであほかなりむずかし
いことであったが、この発明は磁気光学カー回転角θ２
と保磁力Ｈｃの増大１果をもたらす非磁性元素を提供す
るものである。GdFeSn, GdFeB1, etc. have been discovered so far as systems containing quaternary elements such as Fe and other nonmagnetic metal elements. However, the system that is clearly effective among these is a system in which the rare earth element R, which is a magnetic element, and the transition element T are mutually multiplexed. The system is a quaternary system of GdTbCoFe. There are still few examples of systems with non-magnetic elements added. However, as will be explained later, as a result of follow-up tests, no obvious effect was found, which made it difficult for some people to question this. is the magneto-optical Kerr rotation angle θ2
The object of the present invention is to provide a non-magnetic element that increases the coercive force Hc.
次に、この発明の詳細な説明する。Next, the present invention will be explained in detail.
〔実施例１〕
高岡ｆｌｕスバンタ法によって、コーニング７０５９ガ
ラス（商品名）基板」−に、アルゴン圧ＰＡｒ成：２０
ｍＴｏｒｒ 、基板バイアス電圧Ｖｂニー１ｖｌ’。[Example 1] By the Takaoka flu Svanta method, a Corning 7059 glass (trade name) substrate was coated with argon pressure PAr: 20
mTorr, substrate bias voltage Vb knee 1vl'.
スパッタ速度： １８０−２００Ａ／ｍ ｉ ｎ１７Ｉ
条Ｆｅ５ｇなる組成をもつ非晶質垂直磁化膜を作製態で
の磁気光学カー回転角θにの波長依存性を１測定した。Sputtering speed: 180-200A/min17I
The wavelength dependence of the magneto-optic Kerr rotation angle θ was measured in a prepared amorphous perpendicularly magnetized film having a composition of 5 g of Fe stripes.
作製した膜は磁化曲線も角型比（Ｂｌ／Ｂｍ）−１の良
好な垂直磁化膜で、保磁力Ｈｅ！情６ＫＯｅであった。The produced film is a perpendicularly magnetized film with a good magnetization curve and a squareness ratio (Bl/Bm)-1, and a coercive force He! It was 6KOe.
この膜における磁気光学カー回転角θにの波長依存性を
第１図に実線で示した。比較のために、四元系（Ｇｄ７
Ｔｂ、 ４Ｃ。The wavelength dependence of the magneto-optic Kerr rotation angle θ in this film is shown by a solid line in FIG. For comparison, a quaternary system (Gd7
Tb, 4C.
４０ Ｆｅ３９非晶質ｌＩ＠ （Ｈｃ＝ １．４ＫＯｅ
）の磁気光学カー回転角０８の波長依存性もあわせて点
線で示した。40 Fe39 amorphous lI@ (Hc= 1.4KOe
) is also shown by a dotted line.
図のように、紫外光領域を除く全ての波長領域でＤｙを
含む三元系非晶質膜の磁気光学カー回転角θにの値は大
きくなっており、すぐれた光熱磁気記録材ネ４であるこ
とがわかる（この場合膜面を適当な誘電体膜で被覆して
多重反射を起させるとく、また、Ｄｙを添加するとキュ
リ一温度Ｔｉｃガいくらか低下するので、この面でも光
熱磁気ｉｎ材料として好ましいということができる。な
−、磁気光学カー回転角θには、いずれも、光の入射角
１０度で、真空装置から取り出してただちに膜面にて測
定した時の値を示しである。また、この実施例では１つ
の例しか図示しなかったが、第（１）式に示す組成範囲
で垂直磁化膜となることかたしかめられてきた。また、
Ｇｄ−Ｔｂ−ＤＶ−Ｃｏ−Ｆｅ膜に銀（Ａｇ）を約５原
子％だけ添加した膜を作製し、波長２３０〜８００ｎｍ
における磁気光学カー回転角θ、の波長依存性を測定し
たところ、全般に０．３度程度の増加がみとめられ、垂
直磁気異方性Ｋｕの増加と磁化ヒステリシス曲線の角型
化がみとめられた。As shown in the figure, the value of the magneto-optical Kerr rotation angle θ of the ternary amorphous film containing Dy is large in all wavelength ranges except the ultraviolet light region, indicating that it is an excellent photothermal magnetic recording material. (In this case, if the film surface is coated with a suitable dielectric film to cause multiple reflections, and if Dy is added, the Curie temperature Tic will decrease somewhat, so this surface can also be used as a photothermal magnetic in material. It can be said that it is preferable.The magneto-optical Kerr rotation angle θ is the value measured at the film surface immediately after being taken out of the vacuum apparatus at a light incident angle of 10 degrees. Although only one example was shown in this embodiment, it has been confirmed that a perpendicularly magnetized film can be obtained within the composition range shown in equation (1).
A Gd-Tb-DV-Co-Fe film with approximately 5 atomic percent of silver (Ag) added was fabricated to produce a film with a wavelength of 230 to 800 nm.
When the wavelength dependence of the magneto-optical Kerr rotation angle θ was measured, an increase of about 0.3 degrees was observed in general, and an increase in the perpendicular magnetic anisotropy Ku and a squaring of the magnetization hysteresis curve were observed. .
また、Ｇｄ−Ｔｂ−Ｄｙ−Ｃｏ−Ｆｅ合金にＮｂを約３
原子％添加した膜の磁化曲線、保磁力Ｈｅ、磁気光学カ
ー回転角θにの波長依存性を測定したが、保磁力Ｈｃの
増加はみとめられたものの、磁気光学カー回転角θにの
増大は認められなかった（第３図参照）。In addition, approximately 3 Nb was added to the Gd-Tb-Dy-Co-Fe alloy.
We measured the wavelength dependence of the magnetization curve, coercive force He, and magneto-optic Kerr rotation angle θ of the film with atomic % doping, and found that although an increase in the coercive force Hc was observed, an increase in the magneto-optic Kerr rotation angle θ was It was not recognized (see Figure 3).
〔実施例２〕
高周波スパッタ法によって、コーニング７０５９ガラス
（商品名）基板上にアルゴン圧ＢＡ？ｋｒ＃−。[Example 2] Argon pressure BA? was applied onto a Corning 7059 glass (trade name) substrate by high frequency sputtering. kr#-.
２０ｍＴＯｒｒ 、基板バイアス電圧ｖ ｂ ： −１
１Ｖ 。20 mTOrr, substrate bias voltage v b : -1
1V.
スパンタ速度：１８０〜２００人／ｍ１ｎ（７）ｉ条件
で、非晶質（Ｇ ｂ７ Ｔ Ｊ ４ＣＯ４ｏ Ｆ ｅ３
’ａ）ＪｏＯｙＡｇｘ膜を作製し、磁化曲線、保磁力Ｈ
ｅ、磁気光学カー回転角θ２の波長依存性９反射率Ｒｅ
。Spunter speed: 180-200 people/m1n(7) Under i conditions, amorphous (G b7 T J 4CO4o Fe3
'a) Fabricate JoOyAgx film, magnetization curve, coercive force H
e, wavelength dependence of magneto-optic Kerr rotation angle θ2 9 reflectance Re
.
垂直磁気異方性Ｋｕなどを測定した。これらの膜におけ
る保磁力Ｈｃと磁気光学カー回転角θにのＡｇ量による
変化を第２図に示した。磁気光学カー回転角θ２はいず
れも真空装置から取り出した後ただちに膜面で測定した
時の値である。なお、この場合の光の入射角は１０度で
ある。第２図で、○、△２口で示される曲線は磁気光学
カー回転角θＫを示し、・、ム、腸で示される曲線は保
磁力Ｈｅを示す。また、白、黒とも丸はＳｎ。Perpendicular magnetic anisotropy Ku etc. were measured. FIG. 2 shows the changes in coercive force Hc and magneto-optic Kerr rotation angle θ in these films depending on the amount of Ag. All magneto-optical Kerr rotation angles θ2 are values measured at the film surface immediately after being taken out from the vacuum apparatus. Note that the incident angle of light in this case is 10 degrees. In FIG. 2, the curves indicated by ○ and △2 indicate the magneto-optical Kerr rotation angle θK, and the curves indicated by . Also, the white and black circles are Sn.
三角形はＡｇ、四角形はＰＬを添加した場合である。The triangles represent the case where Ag is added, and the squares represent the case where PL is added.
また、一般に、カラス面を通して測定する場合は、これ
らの値より３〜６度大きくなる。結果は１図から明らか
なように、Ａｇの添加によって保磁力Ｈｃが大幅に増大
するほか、磁気光学カー回転角θヮも増大している。さ
らに、Ａｇ量とともに反射率ＲｅもＯ〜４％程度高まる
ことがわかった。また、Ａｇ添加によって磁化曲線の角
型比Ｂｒ／Ｂｍは格段に向上する。Generally, when measuring through the glass surface, the value is 3 to 6 degrees larger than these values. As is clear from FIG. 1, the addition of Ag not only significantly increases the coercive force Hc, but also increases the magneto-optic Kerr rotation angle θヮ. Furthermore, it was found that the reflectance Re increased by about 0 to 4% as the amount of Ag increased. Moreover, the squareness ratio Br/Bm of the magnetization curve is significantly improved by adding Ag.
一般に、Ｒ−Ｔ欣に非磁性元素を添加しても、保磁力Ｈ
ｃ、磁気光学カー回転角θ８．磁化曲線の角型比Ｂ ｒ
／ Ｂ ｍがともによくなるとは限らない。In general, even if a nonmagnetic element is added to the RT core, the coercive force H
c, magneto-optical Kerr rotation angle θ8. Squareness ratio of magnetization curve B r
/ B m does not necessarily improve together.
この例として、第２図では、Ｇｄ、Ｔｂ、 ４〜ｌ Ｓ
ＣＯ４０Ｆｅ３９−３８合金にＳｎとＰＬを添加した
時の保磁力Ｈｃと磁気光学カー回転角θにの変化を示し
たが、両方の膜ともに保磁力Ｈｃは減少する。磁気光学
カー回転角θＫ （飽和磁化状態での値）は、Ｐｔ添加
ではわずかに増大するが、Ｓｎ添加では新派する。この
ように、ＳｎやＰｔは保磁力Ｈｅを著しく減少させるが
、これは垂直磁気異方性Ｋｕが減少するためで、添加量
が多くなるにつれて、磁化曲線の形は蛇行形や面内磁化
膜になったりする。Ｐｔと同じような添加効果を示す元
素には金（Ａｕ）、パラジウム（Ｐｂ）、マンカン（Ｍ
ｎ）等があり、Ｓｎと同じような添加効果を示す元素に
はアンチモン（ｓ ｂ）等がある。また、ニオビウム（
Ｎｂ）等は保磁力Ｈｃは減少させないか磁気光学カー回
転角θＫを減少させる。そして、前記Ａｇと同じように
添加することにより、保磁力Ｈｅと磁気光学カー回転角
θにを増大させる元素にはマグネシウム（Ｍｇ）と銅（
Ｃｕ）等かある。このＡｇ。As an example of this, in FIG. 2, Gd, Tb, 4~l S
The changes in the coercive force Hc and the magneto-optic Kerr rotation angle θ when Sn and PL are added to the CO40Fe39-38 alloy are shown, and the coercive force Hc decreases in both films. The magneto-optical Kerr rotation angle θK (value in the saturated magnetization state) increases slightly with Pt addition, but increases with Sn addition. In this way, Sn and Pt significantly reduce the coercive force He, but this is because the perpendicular magnetic anisotropy Ku decreases, and as the amount added increases, the shape of the magnetization curve becomes serpentine or in-plane magnetized film. It becomes. Elements that exhibit the same additive effect as Pt include gold (Au), palladium (Pb), and manguin (M
Antimony (sb) is an element that exhibits the same additive effect as Sn. Also, niobium (
Nb) etc. do not reduce the coercive force Hc or reduce the magneto-optical Kerr rotation angle θK. Elements that increase the coercive force He and the magneto-optical Kerr rotation angle θ by adding them in the same way as Ag mentioned above include magnesium (Mg) and copper (
Cu) etc. This Ag.
＋４Ｍｇ 、 Ｃｕ等の特徴は、鉄族き固溶しなく、Ｌ
ムに鉄族の磁気モーメントをあまり減少させない−よう
な金属元素である。したがって、逆に言え（ｆ、固溶体
を作らず、磁気モーメントを減少させないような元素な
らば、保磁力Ｈｃや磁気光学カー回転角θＫを増大させ
る可能性かあるということができる。この可能性のある
元素はホウ素（Ｂ）。The characteristics of +4Mg, Cu, etc. are that they do not form a solid solution with iron group members, and L
It is a metal element that does not significantly reduce the magnetic moment of the iron group. Therefore, conversely, if an element does not form a solid solution (f) and does not reduce the magnetic moment, it can be said that there is a possibility of increasing the coercive force Hc and the magneto-optical Kerr rotation angle θK. One element is boron (B).
ガリウム（Ｇａ）、シルコニウｔ、（Ｚｒ）、ハフニウ
ム（Ｈｆ）等である。These include gallium (Ga), silconium (Zr), and hafnium (Hf).
第３図（ａ）〜（」）は、添加元素の種類によって膜の
磁化曲線の形がとのようになるかの例を示したものであ
る。これらの例からもＡｇ。FIGS. 3(a) to 3('') show examples of how the shape of the magnetization curve of the film changes depending on the type of additive element. From these examples also Ag.
Ｍ ｇ 、 Ｃｕを添加した材料の特性かすぐれている
ことかよくわかる。なお、これらは、波長５００ｎｍで
、膜面で測定したもので、ベースに用いたＲ−Ｔ非晶質
合金はすべてＧｄ−Ｔｂ−Ｃｏ−Ｆｅ合金膜である。他
のＲ−Ｔ合金膜でも同様の実験を行ったが、効果は同様
であった。It is clear that the properties of the material to which Mg and Cu are added are excellent. Note that these were measured on the film surface at a wavelength of 500 nm, and all the RT amorphous alloys used for the base were Gd-Tb-Co-Fe alloy films. Similar experiments were conducted with other RT alloy films, but the effects were similar.
〔実施例３〕
実施例１．２と同じ作製条件で、非晶質（Ｔｂ７０ＣＯ
２２）ｔｏｏ−ｘｓｉｘｌ１２を作製し、保磁力Ｈｃと
磁気光学カー回転角θにを測定した。[Example 3] Amorphous (Tb70CO
22) Too-xsixl12 was produced and the coercive force Hc and magneto-optic Kerr rotation angle θ were measured.
その結果を第４図に示した。なお、ＸはＳｉのターゲッ
トに対する面積％で示してあり、実際の原子比とは異な
っている。この図から明らかなように、保磁力Ｈｃはｘ
＝５面積％付近で最大となった後減少している。磁気光
学カー回転角ＯＫは、膜面で測定した場合には１０面積
％あたりまでわずかに増えているが、ガラス面での値は
単調に減少しているので、Ｓｌの添加で磁気光学カー回
転角θイが増大すると明言することはできない。しかし
、すくなくとも、おそらく、原子％で約３％Ｓｉ程度（
面積％を換算予測して）までは、磁気光学カー回転角θ
よ 、保磁力Ｈｃに対し、総合的にみて、プラスの効果
があると考えることができる。The results are shown in Figure 4. Note that X is expressed as an area % of Si with respect to the target, and is different from the actual atomic ratio. As is clear from this figure, the coercive force Hc is x
It reaches a maximum around =5 area% and then decreases. The magneto-optic Kerr rotation angle OK increases slightly to around 10 area% when measured on the film surface, but the value on the glass surface decreases monotonically. It cannot be stated unequivocally that the angle θi increases. However, at least, it is probably about 3% Si in atomic % (
The magneto-optical Kerr rotation angle θ is calculated by converting the area%
Overall, it can be considered that there is a positive effect on the coercive force Hc.
〔実施例４〕
実施例１，２と同じ作製条件のもとで、非晶質（Ｇｄ−
Ｔｂ−Ｃｏ−Ｆｅ） ９８Ｃｕ２合金膜を作製し、磁化
曲線１反射率Ｒｅおよび磁気光学カー回転角ＯＫの波長
依存性を測定した。それぞれの値は、Ｈｃ＝ １．７Ｋ
Ｏｅ 、θＫ （８００ｎｍ）＝１９．６分で、Ｃｕ添
加前のＧｄＴｂＣｏＦｅ膜と比較して、保磁力Ｈｃで、
０．３ＫＯｅ 、磁気光学カー回転角θ２で約１．５分
。[Example 4] Under the same production conditions as Examples 1 and 2, amorphous (Gd-
A Tb-Co-Fe)98Cu2 alloy film was prepared, and the wavelength dependence of the magnetization curve 1 reflectance Re and the magneto-optic Kerr rotation angle OK was measured. Each value is Hc = 1.7K
At Oe, θK (800 nm) = 19.6 min, compared with the GdTbCoFe film before Cu addition, the coercive force Hc,
0.3KOe, about 1.5 minutes at magneto-optical Kerr rotation angle θ2.
反射率Ｒｅで約５％だけ増加することがわかった。また
、角型比（Ｂｒ／Ｂｍ）はｌであった。It was found that the reflectance Re increased by about 5%. Further, the squareness ratio (Br/Bm) was l.
第５図には、はぼ、（ＧｄＴｂＣｏＦｅ） ９ａＣｕ２
の組成をもつ非晶質垂直膜の膜面における磁気光学カー
回転角θ２の波長依存性を点線で示した。なお、測定は
残留磁化状態で行ったものである。また、他の曲線につ
いては後述する。In Figure 5, (GdTbCoFe) 9aCu2
The dotted line shows the wavelength dependence of the magneto-optic Kerr rotation angle θ2 at the film surface of the amorphous vertical film having the composition. Note that the measurements were performed in a residual magnetization state. Further, other curves will be described later.
〔実施例５〕
実施例１と同じ作製条件で、およそ（ＧｄＴｂＣＯＦｅ
）９７Ｍｇ３の組成をもつ非晶質垂直磁化膜を作製した
。Ｈｃ＝２ＫＯｅ 、θＫ （８００ｍｎ）−１９，８
分で、Ｍｇ添加前の第５図の一点鎖線で示すＧｄ−Ｔｂ
−Ｃｏ−Ｆｅ合金に比べて、保磁力Ｈｃで約０．６ＫＯ
ｅ、磁気光学カー回転角θ８で約２分すぐれていた。ま
た、この時の磁気光学カー回転角θにの波長依存性を第
５図に実線で示した。この時の作製測定条件は前記実施
例５の場合と同じである。[Example 5] Approximately (GdTbCOFe
) An amorphous perpendicular magnetization film having a composition of 97Mg3 was fabricated. Hc=2KOe, θK (800mn)-19,8
Gd-Tb shown by the dashed line in Figure 5 before Mg addition
-Compared to Co-Fe alloy, coercive force Hc is about 0.6KO
e, magneto-optical Kerr rotation angle θ8 was superior by about 2 minutes. Further, the wavelength dependence of the magneto-optic Kerr rotation angle θ at this time is shown by a solid line in FIG. The manufacturing and measuring conditions at this time are the same as in Example 5 above.
なお、この発明の説明では基体の非晶質膜として、Ｇｄ
−Ｔｂ−Ｄｙ−Ｃｏ−Ｆｅ 、Ｇｄ−Ｔｂ−Ｃｏ−Ｆｅ
、Ｔｂ−Ｃｏの三種類の膜を用いた場合を主として述
べてきたが、他のＲ−Ｆｅ系やＲ−Ｃｏ系あるいはこれ
らの複合系においても同様の効果があられれる。また、
ここで示した例では磁気光学カー回転角θにの増加分は
少ないが、誘電体膜などで多重反射の効果を利用した時
には、数倍の効果となってあられれることは（１うまで
もない。Note that in the description of this invention, Gd is used as the amorphous film of the base.
-Tb-Dy-Co-Fe, Gd-Tb-Co-Fe
, Tb--Co, but similar effects can be obtained with other R--Fe, R--Co, or composite systems. Also,
In the example shown here, the increase in the magneto-optical Kerr rotation angle θ is small, but it goes without saying that when the effect of multiple reflections is utilized with a dielectric film, the effect can be several times larger (1) .
また、Ｇｄ−Ｔｂ−Ｄｙ−Ｃｏ−ＦｅやＧｄ−Ｔｂ−Ｃ
ｏ−Ｆｅなどをベースとし、ＡｇやＭ ｇ 、 Ｃｕな
どを添加した非晶質合金膜は、一般にベースのキュリ一
温度が高いのでキュリ一点書き込みがむずかしい。その
ため、大きな磁気光学カー回転角θＫが生かされないこ
とがある。これは磁性層を多層化することで解決できる
。つまり、適当なキュリ一温度を有する材料をベースに
し、その上にこの発明に係るキュリ一温度の高Ｑ）材料
を一層以上の多層に光の浸入距離以下の厚みに重ねるこ
と亡事実上一つの媒体にすることが可能である。さらに
、これらの媒体を単層また１ま多層の誘電体膜で覆い多
重反射を利用して増大させるとよりよい媒体となる。Also, Gd-Tb-Dy-Co-Fe and Gd-Tb-C
An amorphous alloy film based on o-Fe or the like to which Ag, Mg, Cu, or the like is added generally has a high Curie temperature of the base, so it is difficult to write a single Curie point. Therefore, the large magneto-optical Kerr rotation angle θK may not be utilized. This problem can be solved by multilayering the magnetic layer. In other words, it is virtually impossible to use a material with a suitable Curie temperature as a base material and to layer one or more layers of the high Curie temperature Q) material according to the present invention to a thickness that is less than the light penetration distance. It is possible to use it as a medium. Furthermore, better media can be obtained by covering these media with a single layer or one or more layers of dielectric film and increasing the amount of light by utilizing multiple reflections.
以上説明したように、この発明に係る光熱磁気記録媒体
は、従来の（Ｒ−Ｔ）系非晶質合金膜に比べて、保磁力
、磁気光学カー回転角９反射率なとがすくれており、読
み出し時のＳ／Ｎや記録ビットの安定性を大幅に改善す
ることができる。As explained above, the photothermal magnetic recording medium according to the present invention has lower coercive force and magneto-optic Kerr rotation angle 9 reflectance than conventional (RT) type amorphous alloy films. Therefore, the S/N ratio during readout and the stability of recorded bits can be significantly improved.
さらに、この発明の材料では垂直磁気異方性が増強され
るため垂直磁化膜になりやすく、角型比（Ｂｒ／’Ｂｍ
）がよくなるほか、キュリ一温度を少し低下させること
ができるので、記録時のパワーがなくてすむ等の利点を
有する。Furthermore, since the material of this invention has enhanced perpendicular magnetic anisotropy, it is easy to form a perpendicularly magnetized film, and the squareness ratio (Br/'Bm
), and the Curie temperature can be lowered a little, so there are advantages such as no need for power during recording.
第１図は非晶賀Ｇｄ７ Ｔｂｌ ａ ＣＯ４、Ｆｅ３８
膜とＧｄ７ Ｔｂ７ Ｄ”／８ Ｃ，０４ｏ Ｆｅ３
ａ膜における磁気光学カー回転角の波長依存性を示した
特性図、第２図はＧｄ−Ｔｂ−Ｃｏ−Ｔｅ膜にＳｎ、Ｐ
ｔ、Ａｇを添加した時の保磁力と磁気光学カー回転角の
変化を示した特性図、第３図（ａ） 〜（ｊ）はＧｄ−
Ｔｂ−Ｃｏ−Ｆｅ膜に非磁性元素（Ｍ＝Ｐｔ、Ａｕ、Ｐ
ｄ、Ｓｎ、Ａｇ。
Ｍｇ、Ｃｕ、Ｓｂ、Ｎｂ）を添した時の磁化曲線の一例
を示した特性図、第４図はＴｂ２２Ｃ。
７８膜にＳｉを添加した時の保磁力と磁気光学カー回転
角の変化を示した特性図、第５図は非晶質（Ｇｄ−Ｔｂ
−Ｃｏ−Ｆｅ）９７ Ｍｇ３合金膜と（Ｇｂ−Ｔｂ−Ｃ
ｏ−Ｆｅ） ９Ｂ Ｃｕ２合金膜およびＧｄ７Ｔｂ１４
Ｃｏ、、１ Ｆｅ３ Ｂ合金膜の残留磁化状態におけ
る磁気光学カー回転角の波長依存性を示した特性図であ
る。
図中、Ｈｃは保磁力、θえはＦｉ１％光学カー回転角、
θＦはファラデイー回転角、Ｒは耗土類元素、Ｔは遷移
元素、Ｋｕは垂直磁気異方性、Ｒｅは反射率、Ｍは他の
金属元素、ＰＡｒｋ−＆は７ノ嚇←〃圧、ｖｂは基板バ
イアス電圧、Ｂｒ／Ｂｍｌｆｊ磁化曲線の角型比、Ｔｃ
はキュリ一温度である。
指定代理人 電子技術総合研究所長 等々力 達ｎ）−
第２図
−ｊ （・
□
ｐ 、ｔｌｌｌｋ 。
ｒ−（４予 ０１０）
第３図
−３０「
−３０［
第３図
（Ｃｘｌ”、ｂＣｏＦｅ）ｑｓＡｇ５３０Ｆθｋ（９）
（１
第３図
０１
（Ｇｄ Ｔｂ Ｃｏ、Ｆｅ）ｓｇＣｕｚ ３０Ｉ””−
３，）（
第４図
１
よ′°」、・
へ １４
Ｓｉ（ｌ！ｌｌ’ｆｆｉ’〕。）Figure 1 shows amorphous Gd7 Tbl a CO4, Fe38
Membrane and Gd7 Tb7 D”/8 C,04o Fe3
Figure 2 is a characteristic diagram showing the wavelength dependence of the magneto-optical Kerr rotation angle in a film.
Characteristic diagrams showing changes in coercive force and magneto-optical Kerr rotation angle when Ag is added, Figure 3 (a) to (j) are Gd-
Non-magnetic elements (M=Pt, Au, P
d, Sn, Ag. A characteristic diagram showing an example of the magnetization curve when adding Mg, Cu, Sb, Nb), FIG. 4 is Tb22C. A characteristic diagram showing the changes in coercive force and magneto-optic Kerr rotation angle when Si is added to the 78 film.
-Co-Fe)97 Mg3 alloy film and (Gb-Tb-C
o-Fe) 9B Cu2 alloy film and Gd7Tb14
FIG. 3 is a characteristic diagram showing the wavelength dependence of the magneto-optic Kerr rotation angle in the residual magnetization state of a Co,,1Fe3B alloy film. In the figure, Hc is coercive force, θ is Fi1% optical Kerr rotation angle,
θF is the Faraday rotation angle, R is a depleting earth element, T is a transition element, Ku is perpendicular magnetic anisotropy, Re is reflectance, M is another metal element, PArk-& is 7 pressure←〃pressure, vb is the substrate bias voltage, the squareness ratio of the Br/Bmlfj magnetization curve, and Tc
is the temperature of a cucumber. Designated agent Tatsu Todoroki Director of Electronic Technology Research Institute qsAg530Fθk(9)
(1 Fig. 3 01 (Gd Tb Co, Fe)sgCuz 30I""-
3,) (Fig. 4 1 yo'°'', 14 Si (l!ll'ffi').)
Claims (2)
成よりなる非晶質光熱磁気記録媒体。 Ｇｂａ Ｔｂｂ Ｄｙｃ Ｃｏｘ Ｆｅｙただし、前記
ａ、ｂ、ｃ、ｘ、ｙはそれぞれ次の組成範囲にあるもの
とする。 ０＜ａ≦１５ 原子％ ｏ＜ｂ≦１５ 原子％ ０＜ｃ≦１５ 原子％ ０＜Ｘ≦４５ 原子％ ４５＜ Ｙ ＜ ８５ 原子％(1) An amorphous photothermal magnetic recording medium having an axis of easy magnetization perpendicular to the film surface and having the following composition. Gba Tbb Dyc Cox Fey However, each of the above a, b, c, x, and y is within the following composition range. 0<a≦15 atomic% o<b≦15 atomic% 0<c≦15 atomic% 0<X≦45 atomic% 45<Y<85 atomic%
類金属Ｒと遷移金属Ｔおよびその他の金属Ｍとかからな
ることを特徴とする光熱磁気記録媒体。 ただし、 ＋ｉｉｊ記Ｍの製置ＸはＯ＜ｘ≦１５原子％
とし、前記ＲはＧｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ。 Ｓｍ、Ｎｃｊ、Ｐｒまたはこれらの複合物とし、前記Ｔ
はＦｅ、Ｃｏ、Ｎｉまたはこれらの複合物とし、前記Ｍ
はＡｇ、Ｍｇ、Ｃｕ、Ｂ、Ｇａまたはこれらの複合物と
する。(2) A photothermal magnetic recording medium comprising a glazed metal R having an axis of easy magnetization perpendicular to the II plane, a transition metal T, and another metal M. However, the production X of +iii M is O<x≦15 atomic%
and R is Gd, Tb, Dy, Ho, Er. Sm, Ncj, Pr or a composite thereof, and the T
is Fe, Co, Ni or a composite thereof, and the M
is Ag, Mg, Cu, B, Ga or a composite thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10908584A JPS60253041A (en) | 1984-05-29 | 1984-05-29 | Photothermomagnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10908584A JPS60253041A (en) | 1984-05-29 | 1984-05-29 | Photothermomagnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60253041A true JPS60253041A (en) | 1985-12-13 |
Family
ID=14501213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10908584A Pending JPS60253041A (en) | 1984-05-29 | 1984-05-29 | Photothermomagnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60253041A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55105832A (en) * | 1979-02-06 | 1980-08-13 | Philips Nv | Thermomagnetic recording carrier |
| JPS5968854A (en) * | 1982-09-28 | 1984-04-18 | Seiko Instr & Electronics Ltd | Photomagnetic recording medium |
| JPS5984358A (en) * | 1982-11-04 | 1984-05-16 | Seiko Instr & Electronics Ltd | Photomagnetic recording medium |
-
1984
- 1984-05-29 JP JP10908584A patent/JPS60253041A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55105832A (en) * | 1979-02-06 | 1980-08-13 | Philips Nv | Thermomagnetic recording carrier |
| JPS5968854A (en) * | 1982-09-28 | 1984-04-18 | Seiko Instr & Electronics Ltd | Photomagnetic recording medium |
| JPS5984358A (en) * | 1982-11-04 | 1984-05-16 | Seiko Instr & Electronics Ltd | Photomagnetic recording medium |
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