JPH01150223A - Thin-film magnetic recording medium - Google Patents
Thin-film magnetic recording mediumInfo
- Publication number
- JPH01150223A JPH01150223A JP30900087A JP30900087A JPH01150223A JP H01150223 A JPH01150223 A JP H01150223A JP 30900087 A JP30900087 A JP 30900087A JP 30900087 A JP30900087 A JP 30900087A JP H01150223 A JPH01150223 A JP H01150223A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- magnetic
- film
- recording medium
- magnetic recording
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 85
- 239000010409 thin film Substances 0.000 title claims description 13
- 239000000758 substrate Substances 0.000 claims abstract description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 7
- 239000001301 oxygen Substances 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims abstract description 4
- 239000010408 film Substances 0.000 claims description 48
- 229910052751 metal Inorganic materials 0.000 claims description 17
- 239000002184 metal Substances 0.000 claims description 17
- 230000001590 oxidative effect Effects 0.000 claims description 2
- 230000007547 defect Effects 0.000 abstract description 12
- 229910052782 aluminium Inorganic materials 0.000 abstract description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 6
- 229910002441 CoNi Inorganic materials 0.000 abstract description 5
- 230000006866 deterioration Effects 0.000 abstract description 4
- 229910018104 Ni-P Inorganic materials 0.000 abstract 1
- 229910018536 Ni—P Inorganic materials 0.000 abstract 1
- 230000015572 biosynthetic process Effects 0.000 abstract 1
- 239000011651 chromium Substances 0.000 description 18
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 10
- 230000001681 protective effect Effects 0.000 description 10
- 238000004544 sputter deposition Methods 0.000 description 8
- 238000005260 corrosion Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 238000007740 vapor deposition Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔概要〕
薄膜型の磁気記録媒体の耐久性改善に関し、磁性層の耐
久性をより確実に向上可能とすることを目的とし、
非磁性の基板に、Ｃｏを主成分とする金属磁性膜が成膜
されている磁気記録媒体において、該金属磁性膜が、当
該金属磁性膜自体を酸化させ、あるいはＣｒ（クローム
）を成膜し、このＣｒ層を酸素雰囲気で加熱処理して形
成した非磁性の酸化膜で覆われているように構成する。[Detailed Description of the Invention] [Summary] With regard to improving the durability of thin-film magnetic recording media, the purpose of this invention is to more reliably improve the durability of the magnetic layer. In a magnetic recording medium on which a metal magnetic film is formed, the metal magnetic film itself is oxidized, or Cr (chromium) is formed into a film, and this Cr layer is heat-treated in an oxygen atmosphere. The structure is such that it is covered with a nonmagnetic oxide film.
〔産業上の利用分野〕 ゛
磁気ディスク装置における記録媒体である磁気記録媒体
には、非磁性の円板に磁性塗料を塗布してなる塗膜型と
、Ｃｏ−ＮｉやＣｏ−Ｐｔなどの磁性金属を成膜して成
る薄膜型と力鴎る。本発明は、後者の薄膜型の磁気記録
媒体の耐久性改善に関する。[Industrial Application Fields] ゛Magnetic recording media, which are the recording media in magnetic disk devices, include a coated type, which is a non-magnetic disc coated with magnetic paint, and a coated type, which is a non-magnetic disk coated with magnetic paint, and a magnetic recording medium, which is a non-magnetic disk coated with magnetic paint. It is a thin film type made by depositing a metal film. The present invention relates to improving the durability of the latter thin film type magnetic recording medium.
第４図は従来の薄膜磁気記録媒体の全容を示す断面図で
ある。■は例えばアルミニウムなどのような非磁性体か
らなる基板（円板）であり、その上に下地層２、磁性層
３、保護膜４の順に積層されている。FIG. 4 is a sectional view showing the entire structure of a conventional thin film magnetic recording medium. 2 is a substrate (disk) made of a non-magnetic material such as aluminum, on which a base layer 2, a magnetic layer 3, and a protective film 4 are laminated in this order.
第５図は従来の磁気記録媒体の断面構造を示す図であり
、磁性層３が酸化鉄（γ−ＦｅｚＯｉ）によって形成さ
れている。基板ｌばアルミニウムからなっており、その
表面を酸化させてアルマイｌ−１ｈ０３）層を形成する
ことで下地層２としている。磁性層３は、γ−Ｆｅ２０
．をスパッタ或いは塗布することで形成される。保護膜
４は、カーボンや５ｉ０２をスパッタすることで形成さ
れる。FIG. 5 is a diagram showing a cross-sectional structure of a conventional magnetic recording medium, in which the magnetic layer 3 is formed of iron oxide (γ-FezOi). The substrate 1 is made of aluminum, and the surface thereof is oxidized to form an aluminium 1-1h03) layer, which serves as the base layer 2. The magnetic layer 3 is made of γ-Fe20
．． It is formed by sputtering or coating. The protective film 4 is formed by sputtering carbon or 5i02.
磁性層３は酸化鉄（７Ｐｅｇ’ｓ）から成り、すでに酸
化していて安定性が良いため、変質して欠陥の原因とな
るようなことは少ない。The magnetic layer 3 is made of iron oxide (7Peg's) and is already oxidized and has good stability, so it is unlikely to change in quality and cause defects.
これに対し、第６図、第７図のように、磁性層３として
、Ｇｏを主成分とする金属磁性膜を用いる場合は、磁性
層３の安定性が悪いために、経年変化により磁性層３が
変質し、欠陥を引き起こし易い。On the other hand, as shown in FIGS. 6 and 7, when a metal magnetic film containing Go as the main component is used as the magnetic layer 3, the stability of the magnetic layer 3 is poor, and the magnetic layer deteriorates over time. 3 is likely to change in quality and cause defects.
第６図は、ＡＩから成る基板１の上に、Ｎ１−Ｐ層２１
とＣｒ層２２から成る下地層２を形成し、その上にＣ０
Ｎｉから成る磁性層３を形成している。保護膜４は、Ｃ
ｒ層４１と０層４２の２層構造になっている。FIG. 6 shows an N1-P layer 21 on a substrate 1 made of AI.
A base layer 2 consisting of a Cr layer 22 is formed, and a C0
A magnetic layer 3 made of Ni is formed. The protective film 4 is made of C
It has a two-layer structure of an r layer 41 and an 0 layer 42.
第７図は、ＡＩから成る基板１の上に、Ｎ１−Ｐ層２１
とＣｒ層２２から成る下地層２を形成し、その上にＣ。FIG. 7 shows an N1-P layer 21 on a substrate 1 made of AI.
A base layer 2 consisting of a Cr layer 22 and a Cr layer 22 is formed, and a Cr layer 22 is formed thereon.
ＮｉＣｒから成る磁性層３、Ｃから成る保護膜４の順に
積層されている。A magnetic layer 3 made of NiCr and a protective film 4 made of C are laminated in this order.
このように、Ｃｏを主成分とする金属膜を用いる磁気記
録媒体は、耐蝕性が劣るので、第５図のように酸化鉄を
用いた磁気記録媒体に比べて、経時変化を来たし易い。As described above, a magnetic recording medium using a metal film containing Co as a main component has poor corrosion resistance and is therefore more susceptible to deterioration over time than a magnetic recording medium using iron oxide as shown in FIG.
そのため、ＳｉＯ□などのような酸化膜で覆ったり、第
６図、第７図のように、ＣｒやＣなどのような耐蝕用保
護膜を成膜している。Therefore, it is covered with an oxide film such as SiO□, or a corrosion-resistant protective film such as Cr or C is formed as shown in FIGS. 6 and 7.
あるいは、第６図のように、磁性膜３中にＣｒを添加し
て耐蝕性の向上を図っている。Alternatively, as shown in FIG. 6, Cr is added to the magnetic film 3 to improve the corrosion resistance.
しかしながら、このような耐蝕性処理を行なっても、保
護膜４によって、磁性層３の酸化を確実に防止すること
はできず、磁性層３の経時変化は避けられない。そのた
め、根本的な解決にはならず、酸化鉄を用いた磁気記録
媒体に比べて、耐久性が劣る。However, even with such anti-corrosion treatment, the protective film 4 cannot reliably prevent oxidation of the magnetic layer 3, and deterioration of the magnetic layer 3 over time is unavoidable. Therefore, it does not provide a fundamental solution, and the durability is inferior to magnetic recording media using iron oxide.
本発明の技術的課題は、従来の金属磁性膜を用いる薄膜
磁気記録媒体におけるこのような問題を解消し、金属磁
性膜の耐久性をより確実に向上可能とすることにある。A technical object of the present invention is to eliminate such problems in conventional thin film magnetic recording media using metal magnetic films and to more reliably improve the durability of metal magnetic films.
第１図は本発明による薄膜磁気記録媒体の基本原理を説
明する図である。ｌは非磁性の基板であり、その上に、
Ｃｏを主成分とする金属磁性膜３が成膜されている。基
板１と金属磁性膜３との間に、適当な材質の下地層を形
成してもよい。FIG. 1 is a diagram explaining the basic principle of a thin film magnetic recording medium according to the present invention. l is a non-magnetic substrate, on which
A metal magnetic film 3 containing Co as a main component is formed. A base layer of an appropriate material may be formed between the substrate 1 and the metal magnetic film 3.
金属磁性膜３は、非磁性の酸化膜５で覆われている。The metal magnetic film 3 is covered with a nonmagnetic oxide film 5.
このように本発明では、安定性の悪い金属磁性膜３が、
酸化膜５で覆われている。この酸化膜５は、すでに酸化
していて、安定性が良いために、保護膜としての機能が
良く、その下の磁性層３の酸化が確実に防止される。そ
の結果、磁性層３の安定性が向上し、経時変化が抑制さ
れ、欠陥の発生率が低下する。In this way, in the present invention, the metal magnetic film 3 with poor stability is
It is covered with an oxide film 5. Since this oxide film 5 has already been oxidized and has good stability, it functions well as a protective film and reliably prevents oxidation of the magnetic layer 3 thereunder. As a result, the stability of the magnetic layer 3 is improved, changes over time are suppressed, and the incidence of defects is reduced.
次に本発明による薄膜磁気記録媒体が実際上どのように
具体化されるかを実施例で説明する。第２図は本発明の
第１実施例を示す断面図である。Next, how the thin film magnetic recording medium according to the present invention is actually implemented will be explained using examples. FIG. 2 is a sectional view showing a first embodiment of the present invention.
アルミニウムなどから成る基板１の上に、下地層２とし
てＮ１−Ｐ層２１とＣｒ層２２が成膜されている。そし
てその上に、ＣｏＮ ｉあるいはＣｏＮ ｉＣｒなどか
ら成る磁性層３が形成されている。磁性層３は、スパッ
タ法やメツキ法、蒸着などの手法で形成される。An N1-P layer 21 and a Cr layer 22 are formed as a base layer 2 on a substrate 1 made of aluminum or the like. A magnetic layer 3 made of CoN i or CoN iCr is formed thereon. The magnetic layer 3 is formed by a method such as a sputtering method, a plating method, or a vapor deposition method.
この実施例では、ＣｏＮｉ等から成る磁性層３の表面を
酸化させることで、表面に酸化膜５ａを形成している。In this embodiment, the surface of the magnetic layer 3 made of CoNi or the like is oxidized to form an oxide film 5a on the surface.
すなわち、磁性層３の成膜後に、大気中で或いは適切な
酸素雰囲気下において、１００〜３００°Ｃで、５〜６
０ｍ１ｎ間加熱処理し、磁性層３の表面のみ酸化させる
。すると、Ｃｏｏ、ＮｉＯに変化し、安定性に優れた酸
化膜５ａとなる。このとき、ＣｏＮ ｉ層３として数百
λ程度成膜し、その表面の数十人程度を強制的に酸化さ
せるのがよい。That is, after forming the magnetic layer 3, it was heated for 5 to 6 hours at 100 to 300°C in the air or under an appropriate oxygen atmosphere.
Heat treatment is performed for 0 m1n to oxidize only the surface of the magnetic layer 3. Then, the oxide film 5a changes to Coo and NiO and has excellent stability. At this time, it is preferable to form a CoN i layer 3 of about several hundred λ and forcibly oxidize about several tens of layers on its surface.
あるいは、連続スパッタ装置において、Ｃｒ層２２の上
に、ＣｏＮ ｉあるいはＣｏＮｉＣｒなどを連続スパッ
タした後、０．０５〜Ｑ、１Ｔｏｒｒの酸素分圧下にお
いて、１００〜３００°Ｃで５〜６抛ｉｎ間加熱し、そ
の後Ｃ膜をスパッタにより成膜してもよい。Alternatively, in a continuous sputtering device, after continuously sputtering CoNi or CoNiCr on the Cr layer 22, sputtering is performed at 100 to 300°C for 5 to 6 inches under an oxygen partial pressure of 0.05 to Q and 1 Torr. After heating, a C film may be formed by sputtering.
このようにして作成した酸化膜５ａの上に、保護膜４と
してＣを成膜する。C is formed as a protective film 4 on the oxide film 5a thus created.
こうして作成された磁気記録媒体を、８０°Ｃ１８０％
の高温多湿雰囲気で、１００時間保持した後、従来の磁
気記録媒体と欠陥増加を比較した。その結、果、従来の
磁気記録媒体は欠陥増加が２〜１０倍であったのに対し
、本発明の磁気記録媒体では、欠陥の増加は認められな
かった。The magnetic recording medium thus created was heated at 80°C180%.
After being held for 100 hours in a high temperature and humid atmosphere, the increase in defects was compared with that of a conventional magnetic recording medium. As a result, while the conventional magnetic recording medium had a 2 to 10 times increase in defects, the magnetic recording medium of the present invention showed no increase in defects.
第３図は本発明の第２の実施例であり、アルミニウムな
どから成る基板１の上に、下地層２としてＮ１−Ｐ層２
１とＣｒ層２２が成膜されている。そしてその上に、Ｃ
ｏＮｉあるいはＣｏＮ ｉｃｒなどから成る磁性層３を
形成している。磁性層３は、ＣｏＮｉ （Ｃｒ）をスパ
ッタ法やメツキ法、蒸着などの手法で形成される。FIG. 3 shows a second embodiment of the present invention, in which an N1-P layer 2 is placed as a base layer 2 on a substrate 1 made of aluminum or the like.
1 and a Cr layer 22 are formed. And on top of that, C
A magnetic layer 3 made of oNi or CoNicr is formed. The magnetic layer 3 is formed of CoNi (Cr) by a sputtering method, a plating method, a vapor deposition method, or the like.
この実施例では、ＣｏＮｉ （Ｃｒ）から成る磁性層３
の表面に、耐蝕性金属としてＣｒを酸素雰囲気中で成膜
する。または、Ｃｒを成膜した後に、大気中であるいは
適切な酸素分圧下で強制的に酸化させることで、Ｃｒ、
０３膜５ｂを形成する。すなわち、磁性層３の上にＣｒ
を成膜した後、大気中において１００〜３００°Ｃで５
ｍｉｎ間程度、強制的に加熱し酸化させる。In this embodiment, a magnetic layer 3 made of CoNi (Cr) is used.
A film of Cr as a corrosion-resistant metal is formed on the surface of the substrate in an oxygen atmosphere. Alternatively, after forming a Cr film, by forcibly oxidizing it in the atmosphere or under an appropriate oxygen partial pressure, Cr,
03 film 5b is formed. That is, Cr is formed on the magnetic layer 3.
After forming a film, it was heated at 100 to 300°C in the atmosphere for 5
Forcibly heat and oxidize for about 10 minutes.
このとき、磁性層３として数百人程度成膜し、その上に
数十人程度の酸化膜５ｂを形成するのが良い。At this time, it is preferable to form the magnetic layer 3 by about several hundred layers, and then form the oxide film 5b by about several tens of layers thereon.
このようにして作成した酸化膜５ｂの上に、保護膜４と
してＣを成膜する。C is formed as a protective film 4 on the oxide film 5b thus created.
この実施例の磁気記録媒体を、８０°Ｃ１８０％の高温
多湿雰囲気で、１００時間保持した後、従来の磁気記録
媒体と欠陥増加を比較した。その結果、従来の磁気記録
媒体は欠陥増加が２〜１０倍であったのに対し、本実施
例の磁気記録媒体では、欠陥の増加は認められなかった
。After holding the magnetic recording medium of this example in a high temperature and high humidity atmosphere of 80°C and 180% for 100 hours, the increase in defects was compared with that of a conventional magnetic recording medium. As a result, while the conventional magnetic recording medium had a 2 to 10 times increase in defects, the magnetic recording medium of this example showed no increase in defects.
以上のように本発明によれば、すでに酸化していて安定
性にすぐれた酸化膜により、磁性層３が覆われているた
め、磁性層３が経時変化により特性変化し、欠陥の原因
となるような問題は解消される。As described above, according to the present invention, since the magnetic layer 3 is covered with an oxide film that has already been oxidized and has excellent stability, the properties of the magnetic layer 3 change over time, causing defects. Such problems will be resolved.
第１図は本発明による薄膜磁気記録媒体の基本原理を説
明する図、第２図は本発明の第１実施例を示す断面図、
第３図は本発明の第２実施例を示す断面図、第４図は薄
膜磁気記録媒体の全容を示す断面図、第５図は従来の酸
化鉄型磁気記録媒体を示す断面図、第６図、第゛７図は
従来の金属磁性膜型磁気記録媒体を示す断面図である。
図において、１は基板、２は下地層、３は磁性層、４は
保護膜、５．５ａ、５ｂは酸化膜をそれぞれ示す。
Ａ象発日月の＃水原浬
第１図
第１大施例
第２図
８２友施例
第３図
第４図
第５図
第６図 第７図FIG. 1 is a diagram explaining the basic principle of a thin film magnetic recording medium according to the present invention, FIG. 2 is a cross-sectional view showing a first embodiment of the present invention,
FIG. 3 is a sectional view showing a second embodiment of the present invention, FIG. 4 is a sectional view showing the entire thin film magnetic recording medium, FIG. 5 is a sectional view showing a conventional iron oxide magnetic recording medium, and FIG. FIG. 7 is a sectional view showing a conventional metal magnetic film type magnetic recording medium. In the figure, 1 is a substrate, 2 is an underlayer, 3 is a magnetic layer, 4 is a protective film, and 5.5a and 5b are oxide films, respectively. #Mizuwon of the sun and moon of A. Fig. 1. Large example. Fig. 2. 82 friend example. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7.
Claims (3)
膜３が成膜されている磁気記録媒体において、該金属磁
性膜３が、非磁性の酸化膜５で覆われていることを特徴
とする薄膜磁気記録媒体。(1) In a magnetic recording medium in which a metal magnetic film 3 mainly composed of Co is formed on a nonmagnetic substrate 1, the metal magnetic film 3 is covered with a nonmagnetic oxide film 5. A thin film magnetic recording medium characterized by:
酸化させることで形成されたものであることを特徴とす
る特許請求の範囲第（１）項記載の薄膜磁気記録媒体。(2) The thin film magnetic recording medium according to claim (1), wherein the oxide film 5 is formed by oxidizing the surface of the metal magnetic film 3.
ｒを成膜し、該Ｃｒ層を、酸素の存在する雰囲気で加熱
処理することで酸化させたものであることを特徴とする
特許請求の範囲第（１）項記載の薄膜磁気記録媒体。(3) The oxide film 5 is formed of C on the metal magnetic film 3.
2. The thin film magnetic recording medium according to claim 1, wherein the Cr layer is oxidized by heat treatment in an atmosphere containing oxygen.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30900087A JPH01150223A (en) | 1987-12-07 | 1987-12-07 | Thin-film magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30900087A JPH01150223A (en) | 1987-12-07 | 1987-12-07 | Thin-film magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01150223A true JPH01150223A (en) | 1989-06-13 |
Family
ID=17987709
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30900087A Pending JPH01150223A (en) | 1987-12-07 | 1987-12-07 | Thin-film magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01150223A (en) |
-
1987
- 1987-12-07 JP JP30900087A patent/JPH01150223A/en active Pending
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