JPS5862825A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To efficiently obtain a magnetic recording medium for high-density recording by the vertical vapor-deposition of an alloy by forming an amorphous continuous film of Si or an Si compound, a discontinuous islandlike bismuth layer and a magnetic thin film of a Co-Ni alloy having a specified composition on a nonmagnetic support in order. CONSTITUTION:A continuous film 2 of Si or an Si compound such as SiO2, Si3N4 or SiC is formed on the surface of a nonmagnetic support 1 in 50-500Angstrom thickness by vapor deposition or other method. A Bi layer 3 is formed on the film 2 in 10-1,000Angstrom thickness, and an Ni-Co alloy layer 4 contg. 30-50atomic% Ni is formed on the layer 3 in 250-500Angstrom thickness by vapor deposition in a high vacuum without requiring a diagonal vapor deposition method. The magnetic layer 4 is provided with sufficient coercive force and square ratio, and a magnetic recording medium suitable for high-density recording is obtd. with high productivity. Since the layers 2, 3 can be vapor-deposited at low boiling points, the magnetic layer can be formed even on a film support with relatively low heat resistance such as a polyester film without causing thermal deformation, etc.

Description

【発明の詳細な説明】 本発明は磁気記録媒体、４９に金属磁性薄膜より成る磁
性層を有する磁気記録媒体に係わる。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording medium having a magnetic layer 49 made of a metal magnetic thin film.

金属薄膜磁性層による磁気記録媒体は、磁性層にバイン
ダーが混入されないことから充填密度の向上をはかるこ
とができ、高密度記録に好適で脚光を浴びるに至ってい
る。Magnetic recording media with metal thin film magnetic layers have been attracting attention because they are suitable for high-density recording and can improve packing density because no binder is mixed into the magnetic layer.

この種、磁気記録媒体の金属磁性層は、コパル）　Ｃｏ
の単体金属、或いはこれにその耐蝕性を向上させるため
のニッケルＮ１や、クロムＣｒを添加したＣｏ−Ｎｉ合
金、或いはＣｏ　−Ｃｒ合金より構成される。The metal magnetic layer of this type of magnetic recording medium is made of copal) Co
, or a Co--Ni alloy to which nickel N1 or chromium Cr is added to improve its corrosion resistance, or a Co--Cr alloy.

このような磁気記録媒体において、高い抗磁力を得るに
、その磁性層の形成に当り、上述した金属を斜め蒸着す
ればよいことが知られている。しかしながら、このよう
な方法による場合、その蒸着方向を被蒸着面に対して４
０°−８０’に傾むける必ｌ！があることから蒸着効率
が低く生産性に問題がある。It is known that in order to obtain a high coercive force in such a magnetic recording medium, the above-mentioned metal may be obliquely deposited when forming the magnetic layer. However, when using such a method, the direction of the vapor deposition is set at 4 degrees with respect to the surface to be vaporized.
It must be tilted to 0°-80'! Because of this, vapor deposition efficiency is low and productivity is problematic.

しかしながら、このような斜め蒸着によらずに高い抗磁
力を有する磁性膜を作製することは容易ではなく１例え
ば結晶磁気異方性が大きく、高抗磁力が得られると期待
される例えばＣＯを単に蒸着してもその抗磁力は１ｏｏ
ｏｅ以下であり、磁気記録媒体としては不適轟である。However, it is not easy to produce a magnetic film with high coercive force without using such oblique deposition. Even if it is vapor deposited, its coercive force is 1oo
oe or less, which is inappropriate for use as a magnetic recording medium.

これに比し１本発明者は、非磁性支持体上に不連続にビ
スマスＢ１を蒸着し、これの上に金ｓａ性膜１例えばＣ
ｏを蒸着することによって高抗磁力の磁性層を得ること
ができるようにした磁気記録媒体を見出すに至ったが、
本発明においては更に安定して確実に、非磁性支持体の
構成材料に依存することなく高い抗磁力の金属磁性膜な
有する磁気記録媒体を提供するものである。In contrast, the present inventor vapor-deposited bismuth B1 discontinuously on a nonmagnetic support, and deposited bismuth B1 on top of this.
We have discovered a magnetic recording medium in which a magnetic layer with high coercive force can be obtained by vapor-depositing o.
The present invention provides a magnetic recording medium having a metal magnetic film having a high coercive force, which is more stable and reliable, regardless of the constituent material of the nonmagnetic support.

すなわち、本発明においては、第１図に示すように非磁
性支持体（１）上に、シリコン８ｉｔたはＳｉの化合物
の非晶質連続膜（２）を被着し、このＩＩ　（２）上に
不連続な島状の８７層（３）を被着形成し、これの上に
磁性層としての金属磁性膜Ｊｌ［（４）として、特にコ
バルトＣローニッケルＮｉ合金より成り、そのＮｉの量
が３０〜５０原子％の組成とされた金属層によって構成
する。このＣｏ−Ｎｉ合金より成る金属磁性薄膜（４）
は１００Ｘ以上〜１ｏｏｏ　１以下、好ましくは２５０
層以上〜５００Ｘ以下例えば３００Ｘとする。因みにこ
の膜厚が１００久より薄いと磁化量が充分にとれず、ま
た１０００Ｘを越えると抗磁力Ｈｅ及び角型比Ｒｓが充
分にとれないことが認められた。なお、この膜厚はこの
層の磁化量から算出した膜厚である。That is, in the present invention, as shown in FIG. 1, an amorphous continuous film (2) of silicon 8it or Si compound is deposited on a nonmagnetic support (1), A discontinuous island-like 87 layer (3) is deposited on top, and a metal magnetic film Jl (4) is formed as a magnetic layer on top of the discontinuous island-like 87 layer (3). It is constituted by a metal layer having a composition of 30 to 50 atomic %. Metal magnetic thin film (4) made of this Co-Ni alloy
is 100X or more to 1ooo 1 or less, preferably 250
500X or less, for example, 300X. Incidentally, it has been found that if this film thickness is thinner than 100X, sufficient magnetization cannot be obtained, and if it exceeds 1000X, sufficient coercive force He and squareness ratio Rs cannot be obtained. Note that this film thickness is calculated from the amount of magnetization of this layer.

非磁性支持体（１）は、磁気記録媒体の使用目的に適し
た任意の材料、例えばポリエステルフィルムを始めとし
てポリイミドフィルム、或いはＡＱ板、ガラス板、セラ
ミック板等を用い得る。The non-magnetic support (1) may be any material suitable for the purpose of use of the magnetic recording medium, such as polyester film, polyimide film, AQ plate, glass plate, ceramic plate, etc.

この非磁性支持体（１）上に、順次被着するＳｉまたは
Ｓ！化合物は、ＳＩ単体の膜、或いは８ｉ０２．８ｉ３
Ｎ４、ＳｉＣ等のＳｔの化合物膜をｓｏｌ〜５ｏｏｌ。Si or S! is sequentially deposited on this non-magnetic support (1)! The compound is a single SI film or 8i02.8i3
St compound film such as N4 and SiC is sol~5oool.

例えばｚｏｏ、ｔｓ度の厚さにこれが連続膜となるよう
に蒸着、スパッタ等によって形成し得る。ここに非晶質
連続膜（２）の厚さを５０Ｘ〜５００Ｘに選定すること
が望ましい理由は、５０層未満では連続膜が得−くなっ
てくること、　ＳＯＯ又を超えると、この膜（２）が結
晶化してくることと、媒体において非磁性部分が占める
厚さが大となり過ぎることに因る。For example, it can be formed by vapor deposition, sputtering, etc. so as to form a continuous film to a thickness of 100 to 200 mm. The reason why it is desirable to select the thickness of the amorphous continuous film (2) from 50X to 500X is that if the thickness is less than 50 layers, it becomes difficult to obtain a continuous film, and if the thickness exceeds SOO, this film ( 2) is crystallized and the thickness occupied by the non-magnetic portion of the medium becomes too large.

また、この非晶質連続膜（２）上に形成する８７層（３
）は、蒸着によって形成し得るが、この場合これが不連
続な島状の膜として形成されるためには、その蒸着に当
っての被蒸着体、すなわち非磁性支持体（１）の温度、
すなわち、いわゆる基体温度は１、：。In addition, 87 layers (3) formed on this amorphous continuous film (2)
) can be formed by vapor deposition, but in this case, in order to form it as a discontinuous island-like film, the temperature of the object to be vaporized, that is, the non-magnetic support (1) during the vapor deposition,
That is, the so-called substrate temperature is 1:.

１３０℃以上で且つＢ１の融点以下の例えば１５０℃に
選ばれる。またこの８７層（３）は、その平均膜厚が１
０層以上〜ｌ０ＧＯ１以下（１ｔｓｇ　／ｒｘａ２〜１
００　ｐｇ／ｃａｂ２）、好ましくは１００Ｘ以上〜１
０００Ｘ以下（１６、ａｇ　／（ＩＩ”〜１００μｇ／
ａｓ”　）の例えば２００Ｘとする。但しカッコ内は平
均膜厚を１鋤２当りの出量で換算したときの値である。The temperature is selected to be 130°C or higher and lower than the melting point of B1, for example 150°C. Moreover, the average thickness of this 87 layer (3) is 1
0 layer or more to 10GO1 or less (1tsg/rxa2 to 1
00 pg/cab2), preferably 100X or more to 1
000X or less (16, ag / (II" ~ 100 μg /
for example, 200X. However, the value in parentheses is the value when the average film thickness is converted into the amount of output per 2 plows.

第２図は本発明に適用される蒸着装置の概略を示すもの
である。同図において、ａυは真空ポンプによる排気α
２によって例え□ば真空度１０　〜１゜Ｔｏｒｒとなし
た真空容器を示し、この容器αυ内に蒸発源α謙と被蒸
着体の非磁性支持体（１）が配される。FIG. 2 schematically shows a vapor deposition apparatus applied to the present invention. In the same figure, aυ is the exhaust α by the vacuum pump
For example, □ represents a vacuum vessel having a vacuum degree of 10 to 1 Torr, and an evaporation source α and a non-magnetic support (1) for the object to be evaporated are arranged within this vessel αυ.

この非磁性支持体（１）は基板ホルダー（Ｉ！１９によ
って支持され、且つ基板ホルダーαＳに供給される熱媒
体αｅによって所定の基板温度に保持される。蒸発源α
濁は例えば電子ビームの衝撃により加熱蒸発される。な
お蒸発源ａ３の蒸発は、抵抗加熱法、高周波誘導加熱法
によることもできる。又非磁性支持体αりと蒸発源α３
との間にはシャッターａηが配される。This non-magnetic support (1) is supported by a substrate holder (I!19) and is maintained at a predetermined substrate temperature by a heating medium αe supplied to a substrate holder αS.Evaporation source α
The turbidity is heated and evaporated by, for example, bombardment with an electron beam. Note that the evaporation of the evaporation source a3 can also be performed by a resistance heating method or a high frequency induction heating method. Also, non-magnetic support α and evaporation source α3
A shutter aη is arranged between the two.

噸、上鉤では非磁性支持体上［Ｓｆ、Ｂｊ−下地層及び
Ｃｏ−Ｎｉ層の３層構造とした場合であるが。In the case of the upper hook, a three-layer structure of Sf, Bj-base layer and Co--Ni layer was used on the non-magnetic support.

必要な磁束をとるため１ｃｓｉ、８７層及びＣｏ−Ｎｉ
層の３層構造を基本とした磁性薄膜を多層化することも
可能である。1csi, 87 layers and Co-Ni to obtain the necessary magnetic flux.
It is also possible to multilayer a magnetic thin film based on a three-layer structure.

次に本発明による実施例を説明する。Next, embodiments according to the present invention will be described.

実施例１ 第３図に示すようにポリエステル（ポリエチレンテレフ
タレート）フィルムより成る非磁性支持体（１）上に、
これの温度、すなわち被蒸着体の基体温度１５０℃とし
て夫々第２図による装置を用いて、夫々電子銃加熱によ
り引の非晶質連続膜（２）を２００Ｘの厚さに蒸着し、
これの上に不連続の島状のＢｉ蒸着属（３）を２００Ｘ
の平均膜厚に蒸着し、更にこれの上ｉｔ、Ｃｏ−Ｎｉ合
金磁性薄膜（４）を３００Ｘの厚さに蒸着し、更にこれ
の上に繰返えし、２００ｘの厚さのＳｉ非晶質連続膜（
２）、平均膜厚が２００１の不連続の島状のＢｉ蒸着膜
（３）、　３００にの厚さのＣｏ−Ｎｉ合金磁性薄膜（
４）を夫々順次蒸着して磁気記録媒体Ｓを得た。Example 1 As shown in Figure 3, on a non-magnetic support (1) made of polyester (polyethylene terephthalate) film,
Using the apparatus shown in FIG. 2 at this temperature, that is, the substrate temperature of the object to be evaporated, 150° C., an amorphous continuous film (2) was deposited to a thickness of 200× by heating with an electron gun.
On top of this, discontinuous island-shaped Bi evaporated metal (3) was placed at 200X
Then, a Co-Ni alloy magnetic thin film (4) is deposited to a thickness of 300X, and then a Co-Ni alloy magnetic thin film (4) is deposited to a thickness of 300X. quality continuous membrane (
2), a discontinuous island-shaped Bi vapor deposited film with an average thickness of 200 mm (3), a Co-Ni alloy magnetic thin film with a thickness of 300 mm (
4) were sequentially deposited to obtain a magnetic recording medium S.

この構成による媒体８において各Ｃｏ−Ｎｉ磁性薄ＩＩ
　（４）のＮｉの量ｔ−３０原子％、　４Ｇ原子％、５
０原子九に選定した媒体を作製し、夫々試料Ｓｌ−８２
、Ｂ３とした。In the medium 8 with this configuration, each Co-Ni magnetic thin II
Amount of Ni in (4) t-30 atomic%, 4G atomic%, 5
A medium with 0 atoms and 9 atoms was prepared, and each sample Sl-82
, B3.

一方、上述の冥施例において各Ｃｏ−Ｎｉ磁性薄Ｍ（４
）のＮｉの童を０原子先、すなわちＣｏ単体とした場合
、５原子％とした場合、１０原子％とじた場合、２０原
子ちとした場合、１００原子％とした場合を比較のため
作製し、これらを夫々試料Ｃ１、Ｃ２、Ｃ３，Ｃ４及び
Ｃ５とした。On the other hand, in the above-mentioned example, each Co-Ni magnetic thin M (4
) were prepared for comparison when the Ni element was set at 0 atoms, that is, Co alone, when it was set at 5 at%, when it was combined at 10 at%, when it was set at 20 atoms, and when it was set at 100 at%, These were designated as samples C1, C2, C3, C4 and C5, respectively.

そして夫々の試料の磁気特性を測定した。その結果を表
１に示す。Then, the magnetic properties of each sample were measured. The results are shown in Table 1.

表　１ この磁気特性の測定は、振動試料型磁力針（ＶＳＭ）で
測定したものであり、外部磁界は５０ｅとした。Table 1 The magnetic properties were measured using a vibrating sample magnetic needle (VSM), and the external magnetic field was 50e.

表１から明らかなように、Ｃｏ−Ｎ五合金磁性薄膜のＮ
ｉ量を３０〜５０原子九とするとき、抗磁力Ｈｃは１３
０００ｅとすることができ、ここに本発明においてＮｉ
量を３０〜５０原子％に特定する所以がある。As is clear from Table 1, the N of the Co-N five-alloy magnetic thin film
When the amount of i is 30 to 50 atoms, the coercive force Hc is 13
000e, where in the present invention Ni
There is a reason why the amount is specified to 30 to 50 atomic %.

尚、各層（２）〜（４）の付着力を上げるために、その
蒸着に当り、適宜酸素の導入を行ってボンバード処理ｔ
ｍすようｋすることができる。In order to increase the adhesion of each layer (2) to (4), during the vapor deposition, oxygen is appropriately introduced and bombarded.
You can do as you like.

上述したよ５）Ｃ本発明による磁気記録媒体は、斜め蒸
着によらずして高枕磁力の磁性層を得ることができるの
で、蒸着効率を高めることができ、更に、特に本発明に
よるときは、ベース、すなわち非磁性支持体の材料によ
らずＫすぐれた磁気特性の媒体を得ることができた。こ
れがため、各種使用態様、目的に応じて廉価な材料によ
って支持体を構成することができる。すなわち本発明に
おいては、支持体上に非晶質、、、、層、特に非晶質層
を作り易い、８１又は８ムの化合物層（２）を形′成し
たことにより、支持体の結晶学約１ＩＰを回避でき、こ
の状態でＢｌの蒸着がなされ、これの上に金属磁性薄膜
Ｃｏ−Ｎｆの蒸着がなされるので、Ｂｉの不連続層によ
ってこれの上のＣｏ−Ｎ１の配向をより効果的になすこ
とができるものと思われる。As mentioned above, 5)C The magnetic recording medium according to the present invention can obtain a magnetic layer with high magnetic force without using oblique deposition, so that the deposition efficiency can be increased. It was possible to obtain a medium with excellent magnetic properties regardless of the material of the base, that is, the nonmagnetic support. Therefore, the support can be constructed from inexpensive materials depending on various usage modes and purposes. That is, in the present invention, an amorphous layer, especially an amorphous layer, is formed on the support, and a compound layer (2) of 81 or 8 μm is formed on the support. In this state, Bl is deposited and a metal magnetic thin film Co-Nf is deposited on top of this, so the discontinuous layer of Bi can improve the orientation of Co-N1 on top of it. It seems that this can be done effectively.

又、非磁性支持体としてポリエチレンテレフタレートの
如き比較的耐熱性に乏しい高分子フィルムを用いた場合
においても、その高分子フィルム上に先ず第１層として
低沸点例えばＳｉ層及び用層を蒸着するものであり、こ
れら８ｉ、Ｂｉ層蒸着に際しての蒸発の加熱パワーは少
なくて済み、高分子フィルムへの熱輻射は小さいもので
あるから高分子フィルムへの熱的影響は小さく、次いで
比較的高沸点で加熱パワーの大きいＣｏ−Ｎｉ層を蒸着
してもこのときの熱輻射は強いがこれの下のＳｉ。Furthermore, even when a polymer film with relatively poor heat resistance such as polyethylene terephthalate is used as a nonmagnetic support, a low boiling point layer such as a Si layer and a silicon layer are first deposited on the polymer film as a first layer. The heating power for evaporation during evaporation of these 8i and Bi layers is small, and the thermal radiation to the polymer film is small, so the thermal influence on the polymer film is small. Even if a Co--Ni layer with high heating power is deposited, the thermal radiation at this time is strong, but the Si below this layer.

Ｓｉ層の介在によって高分子フィルムへの熱輻射が抑制
されるので、この熱輻射による熱変形が回避されるとい
う利益もある。Since thermal radiation to the polymer film is suppressed by the presence of the Si layer, there is also the advantage that thermal deformation due to this thermal radiation can be avoided.

【図面の簡単な説明】[Brief explanation of drawings]

第１図及び第３図は夫々本発明の磁気記録媒体の例を示
す拡大断面図、第２図は本発明に適用される蒸着装置の
概略図である。 （１）は非磁性支持体、（２）は別又はＳｉ化合物層、
（３）はＢｉ下地層、（４）は金属磁性薄膜Ｃｏ−Ｎｉ
合金層である。1 and 3 are enlarged sectional views showing examples of the magnetic recording medium of the present invention, respectively, and FIG. 2 is a schematic diagram of a vapor deposition apparatus applied to the present invention. (1) is a non-magnetic support, (2) is a separate or Si compound layer,
(3) is a Bi underlayer, and (4) is a metal magnetic thin film Co-Ni.
It is an alloy layer.

Claims (1)

【特許請求の範囲】[Claims] 非磁性支持体上に、シリコンまたはシリコンの化合物の
非晶質連続膜と、不連続に島状に形成されたビスマス層
と、金属磁性薄膜とが順次被着されて成る磁気記録媒体
において、上記金属磁性薄膜がコバルトＣローニッケル
Ｎ３合金より成り、且つそのＮｉ量が３０〜５０原子％
に選ばれて成る磁気記録媒体。A magnetic recording medium in which an amorphous continuous film of silicon or a silicon compound, a bismuth layer discontinuously formed in the form of islands, and a metal magnetic thin film are sequentially deposited on a nonmagnetic support. The metal magnetic thin film is made of a cobalt-C rho-nickel N3 alloy, and the Ni content is 30 to 50 at%
A magnetic recording medium selected from