JPS6361410A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS6361410A JPS6361410A JP20498486A JP20498486A JPS6361410A JP S6361410 A JPS6361410 A JP S6361410A JP 20498486 A JP20498486 A JP 20498486A JP 20498486 A JP20498486 A JP 20498486A JP S6361410 A JPS6361410 A JP S6361410A
- Authority
- JP
- Japan
- Prior art keywords
- film
- magnetic recording
- recording medium
- magnetic
- vapor deposition
- 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 37
- 238000000034 method Methods 0.000 claims abstract description 12
- 239000010409 thin film Substances 0.000 claims abstract description 10
- 229910001337 iron nitride Inorganic materials 0.000 claims abstract description 7
- 238000007740 vapor deposition Methods 0.000 claims abstract description 7
- 239000002184 metal Substances 0.000 claims abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims abstract description 6
- 239000000758 substrate Substances 0.000 claims abstract description 5
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 3
- 239000010941 cobalt Substances 0.000 claims abstract description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 3
- 238000004544 sputter deposition Methods 0.000 claims description 2
- 239000010408 film Substances 0.000 abstract description 20
- 238000005260 corrosion Methods 0.000 abstract description 9
- 230000007797 corrosion Effects 0.000 abstract description 9
- 150000002500 ions Chemical class 0.000 abstract description 8
- 230000005415 magnetization Effects 0.000 abstract description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 7
- 238000001816 cooling Methods 0.000 abstract description 7
- 238000010894 electron beam technology Methods 0.000 abstract description 6
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 4
- 238000010438 heat treatment Methods 0.000 abstract description 2
- 229920006254 polymer film Polymers 0.000 abstract description 2
- 238000001035 drying Methods 0.000 abstract 1
- 238000005121 nitriding Methods 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 9
- 238000001704 evaporation Methods 0.000 description 6
- 230000008020 evaporation Effects 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 230000007423 decrease Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000000696 magnetic material Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910020630 Co Ni Inorganic materials 0.000 description 2
- 229910002440 Co–Ni Inorganic materials 0.000 description 2
- 229910000990 Ni alloy Inorganic materials 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- -1 polyethylene terephthalate Polymers 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 229910002441 CoNi Inorganic materials 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000007733 ion plating Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
（イ）産業上の利用分野
不発Ｆ！Ａは、高密度記録が可能な耐蝕性に優れた磁気
テープ、磁気ディスク等の磁気記録媒体に関するもので
ある。[Detailed description of the invention] (a) Industrial application field failure F! A relates to magnetic recording media such as magnetic tapes and magnetic disks that are capable of high-density recording and have excellent corrosion resistance.
（ロ）従来の技術
磁気記録の高密度化の要求に伴い、真空蒸着法、スパッ
タリング法、イオンプレーティンク法等の乾式４＠形成
法による磁気記録媒体が提唱さ九ている。これらの乾式
薄膜形成法によって形成された磁気記録媒体は、■残留
磁束密度が高い、■保磁力（以下Ｈｅ）が大きい、■磁
性層を薄くできる等の特徴を有する為、従来の塗布型磁
気記録媒体に比べ本質的に高密度記録が可能である。(b) Prior Art With the demand for higher density magnetic recording, magnetic recording media using dry formation methods such as vacuum evaporation, sputtering, and ion plating have been proposed. Magnetic recording media formed by these dry thin film forming methods have the following characteristics: ■ high residual magnetic flux density, ■ large coercive force (hereinafter referred to as He), and ■ ability to make the magnetic layer thinner. Compared to recording media, high-density recording is essentially possible.
そして、この種の磁気記録媒体の磁性材料としては、Ｎ
ｉを２０〜３０Ｑ ％含んだＣｏ−Ｎｉ合命が主に用い
られている。（Ｎａｔｆｏｎａｌ Ｔｅｃｈｎｉｃａ
ｌ Ｒｅｐｏｒｔ、ｖｏｌ、３１．ＮＯ，６，１９８
５年「ビデオ用蒸着テープ」）シかしながら、この合金
はＣｏを７０％以上含む為極めて１価となり、ま之高温
高湿下での１１８雌性も十分ではないという欠点がある
。かかる点を改答する為、近年磁性材料として窒化鉄（
ＦｅＮ系）を用い念ものが提案され、注目されている。The magnetic material for this type of magnetic recording medium is N
Co--Ni alloy containing 20 to 30 Q% of i is mainly used. (Natfonal Technica
l Report, vol. 31. NO, 6,198
However, since this alloy contains more than 70% Co, it is extremely monovalent, and its 118 femininity under high temperature and high humidity conditions is not sufficient. In order to correct this point, iron nitride (iron nitride) has recently been used as a magnetic material.
A prototype using FeN-based materials has been proposed and is attracting attention.
（第９回日本応用磁気学会概要集２９ａＡ−４，１９８
５年ｒ高１ｍ蝕性ＦｅＮ系磁性４模」或は特開昭６Ｏ−
２ｓ０２ｓ号）この材料を用いることにより、ＣｏＮｉ
系Ｑ′こ比べ安価でかつ耐蝕性に浸れた磁気記録媒体カ
ニ得られ、かつＨｃ ｒ角形比共Ｃｏ−Ｎｉ系と同等の
特性を持つ磁気記録媒体が得られる。(9th Japanese Society of Applied Magnetics Abstracts 29aA-4, 198
5 years r height 1 m corrosive FeN-based magnetic 4 model” or JP-A-6O-
2s02s issue) By using this material, CoNi
Compared to the system Q', a magnetic recording medium which is less expensive and has excellent corrosion resistance can be obtained, and a magnetic recording medium having characteristics similar to those of the Co--Ni system in terms of Hcr squareness ratio can be obtained.
しかしながら、ＦｅＮ系薄膜でＨｃを大きくする為ＫＩ
−１膜の窒化度を高める必要があるが、それに伴い膜の
飽和磁化（以下Ｍｓ）が低下してしまう欠点がある。例
えばＨｃ＝１００００ｅを有する磁性層を形成する場合
、Ｃｏ−Ｎｉ系ではＭｓ＝４５０ｅｒｒＢ１／ｃｃであ
るのに対し、ＦｅＮ系ではＭ ｓ ＝ ２２０ ｅｍｒ
１／ｃｃ まで低下させる必要があり、磁気記録媒体と
して利用し之場合に再生出力がＣｏ−Ｎ１系に比べ低下
するという問題点があった。However, in order to increase Hc with a FeN-based thin film, KI
Although it is necessary to increase the degree of nitridation of the −1 film, there is a drawback that the saturation magnetization (hereinafter referred to as Ms) of the film decreases accordingly. For example, when forming a magnetic layer having Hc = 10000e, Ms = 450 errB1/cc in Co-Ni system, whereas M s = 220 emr in FeN system.
1/cc, and when used as a magnetic recording medium, there was a problem that the reproduction output was lower than that of the Co-N1 system.
（ハ）発明が解決しようとする問題点
本発明は、かかる点に鑑み、従来のＦｅＮ系磁性材料を
上回る飽和磁化金有し、かつＦｅＮ系と同様に耐蝕性に
優れ九安価な磁気記録謀体全得ることを課題とするもの
である。(c) Problems to be Solved by the Invention In view of these points, the present invention provides an inexpensive magnetic recording method that has saturation magnetization higher than conventional FeN-based magnetic materials, has excellent corrosion resistance like FeN-based materials, and is inexpensive. The challenge is to gain the whole body.
に）問題点を解決するための手段
１乃至１０原子％のコバルトを含む鉄窒化物を主成分と
する金属薄膜を非磁性基体上に乾式薄膜形成法によって
形成する。B) Means for Solving the Problem A metal thin film mainly composed of iron nitride containing 1 to 10 atomic % of cobalt is formed on a nonmagnetic substrate by a dry thin film forming method.
（ホ）作 用 本発明の磁気ｅ録媒体の磁性層の原子組成比は、 （Ｆｅ１−ｘｃｏｔ）１ ｙ−Ｎｙ 但し ０．０１≦、≦０．１０ ｏ、、ｒ ｏ≦ｙ≦０．３５ となる。(e) Production The atomic composition ratio of the magnetic layer of the magnetic e-recording medium of the present invention is: (Fe1-xcot)1 y-Ny However, 0.01≦, ≦0.10 o,,r o≦y≦0.35 becomes.
この結果飽和磁化Ｍｓｆ：低下することなく十分な耐蝕
性を得ることが出来る。As a result, sufficient corrosion resistance can be obtained without decreasing the saturation magnetization Msf.
（へ）実施例
以下本発明の詳細を図面を参照しつつ説明する０
第１図は、乾式薄膜形成法の一例として蒸着法を用いる
場合の装置の略図を示すものである。(F) EXAMPLES The details of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic diagram of an apparatus in which a vapor deposition method is used as an example of a dry thin film forming method.
この装置においては、真空槽（］）内に、フ、（／ｌ／
ム供袷ローラ（２）、フィルム巻取りローラ（３）、冷
却キャン（４）、蒸着源（７）及びその収納容器（８）
、カウフマン型イオン銃（川音配置し、ポリエチレンテ
レフタレート（ＰＥＴ）、ポリイミド等のテープ状の高
分子フィ）ｖム（６）全供給ローラ（２）から繰り出し
、冷却キャン（４）を経て巻取りローラ（３）へ定速移
送する構成とする。In this device, in the vacuum chamber (]), (/l/
Mu supply roller (2), film winding roller (3), cooling can (4), vapor deposition source (7) and its storage container (8)
, Kaufman type ion gun (Kawane arrangement, tape-shaped polymer film made of polyethylene terephthalate (PET), polyimide, etc.) vm (6) is fed out from the entire supply roller (2), passed through the cooling can (4), and then transferred to the take-up roller. (3) The structure is such that it is transferred at a constant speed.
また前記蒸着源（７）は冷却キャン（４）と対向して配
置し、蒸Ｎ！源（７）中の金属が電子ビームにより加熱
され、蒸気流となって冷却キャン（４）上のフィルム基
板６上に堆積する様に構成する。このとき蒸気流のフィ
ルム（６）に対する最小入射角θは約５５°になる様に
遮蔽板（９）Ｋより制限する。また、ガス導入口０濁よ
り前記カウフマン型イオン銃圓に導入される窒素ガスは
イオン銃（１１）内でイオン化され、蒸気流と同時にフ
ィルム（６）上、入射する。Further, the vapor deposition source (7) is arranged opposite to the cooling can (4), and the vapor deposition source (7) is arranged opposite to the cooling can (4). The arrangement is such that the metal in the source (7) is heated by the electron beam and deposited in a vapor stream on the film substrate 6 on the cooling can (4). At this time, the minimum incident angle θ of the vapor flow with respect to the film (6) is limited to approximately 55° by the shielding plate (9)K. Further, nitrogen gas introduced into the Kauffman type ion gun through the gas inlet port is ionized in the ion gun (11) and is incident on the film (6) at the same time as the vapor flow.
この方式では、蒸着源（７）の蒸発速度及び基板に入射
する窒素イオンの電流密７′ｆ全制御することにより、
形成される磁性層の窒化度を任意に制御することができ
る。より実際的には、蒸着源−７）を加熱する電子ビー
ム電力と、イオン銃内のグロー放電電ｔＮにより磁性層
中の窒化、度を制御する方法が採用されよう。尚、真空
槽１１）中の窒素圧力は１×１０”””ＴｏｒｒＫ保持
する。In this method, by fully controlling the evaporation rate of the evaporation source (7) and the current density 7'f of nitrogen ions incident on the substrate,
The degree of nitridation of the formed magnetic layer can be controlled arbitrarily. More practically, a method may be adopted in which the degree of nitridation in the magnetic layer is controlled by the electron beam power for heating the evaporation source-7) and the glow discharge current tN in the ion gun. Note that the nitrogen pressure in the vacuum chamber 11) is maintained at 1×10""" TorrK.
次に本発明の磁気記録媒体と比較例について説明する。Next, a magnetic recording medium of the present invention and a comparative example will be explained.
比較例の磁気記録媒体の製造条件
・蒸発源 １００％Ｆｅ
・電子ビーム電力 ５．０〜１０．０ｋｗ・窒素
イオン電流 ０． Ｉ Ａ／ ｃｍ２・フィルム
送り速度 ５．０〜１０．Ｏｍ／ｍｉｎ・磁性層厚
０．２μｍ
・最小入射角 ６００
この比較例では、電子ビーム電力が大きい程得られる磁
性膜の窒化度は小さくなり、飽和磁化（Ｍ ３ ）が大
きくなる。第２図（Ｎは、形成之れ念磁性膜のＭｓとＨ
ｃの関係を示す。窒化度が進むに従いＨｃが増加し、Ｍ
ｓ ＝ ２２０ ｅｍｎ／ｃｃ の時Ｈｃ＝１０００
０ｅが得られる。Manufacturing conditions for magnetic recording medium of comparative example - Evaporation source 100% Fe - Electron beam power 5.0 to 10.0 kw - Nitrogen ion current 0. I A/cm2・Film feed speed 5.0-10. Om/min・Magnetic layer thickness 0.2 μm・Minimum incident angle 600 In this comparative example, the higher the electron beam power, the lower the degree of nitridation of the obtained magnetic film, and the higher the saturation magnetization (M 3 ). Figure 2 (N is Ms and H of the formed pneumatic film)
This shows the relationship between c. As the degree of nitridation progresses, Hc increases, and M
When s = 220 emn/cc, Hc = 1000
0e is obtained.
本発明の磁気記録媒体の製造条件
・蒸発＃ ９９４４Ｆｅ−１％Ｃｏ、９５％Ｆｅ−５％
Ｃｏ 、９０％Ｆｅ−１０９６Ｃｏ 、他の形成条件は
比較例と同様とした。第２図Ｂｌ、Ｂ２゜Ｂ８は、それ
ぞれＣｏを１．０原子％、５．０原子％１０原子％とし
之ときの磁性膜のＭＳとＨｅの関係を示すものである。Manufacturing conditions and evaporation # of the magnetic recording medium of the present invention: 9944Fe-1%Co, 95%Fe-5%
Co, 90% Fe-1096Co, and other formation conditions were the same as in the comparative example. FIGS. 2B1, B2 and B8 show the relationship between the MS and He of the magnetic film when Co is 1.0 atomic %, 5.0 atomic % and 10 atomic %, respectively.
この図よりＣＯの添加量が増す【従い、同じＭｓ（窒化
度）の時のＨｃＯ値が大きくなっていることがわかる。From this figure, it can be seen that as the amount of added CO increases, the HcO value increases at the same Ms (degree of nitridation).
以上の結果から、ｃｏ添加量を０％、１％、５優、１０
％と増加するに従って、Ｈｃ＝１００００ｅの得られる
Ｍｓが２２０．３００，４５０゜６００ ｅｍｎ／ｃ’
ｃ 、と大きくなることがわかる。From the above results, the amount of co added is 0%, 1%, 5%, 10%.
%, the obtained Ms of Hc=10000e becomes 220.300,450°600 emn/c'
It can be seen that the value increases to c.
尚、Ｃｏ−Ｎｉ合金を用いた場合には第２図Ｃに示した
様に、Ｍｓ＝４５０ｅｍｎ／ｃｃの時Ｈｃ＝１０００
０ｅ となる◎
以上より、ＦｅＮ膜にＣｏｆ添加するとＭｓの向上に有
効であり、また５％以上ＣＯを添加することによりＣｏ
−Ｎｉ系と同等もしくけそれ以上の磁気特性を有する磁
性膜が得られることが判る。In addition, when Co-Ni alloy is used, as shown in Fig. 2C, when Ms = 450 emn/cc, Hc = 1000
0e◎ From the above, adding Cof to the FeN film is effective in improving Ms, and adding 5% or more of CO increases Co
It can be seen that a magnetic film having magnetic properties equal to or superior to those of the -Ni system can be obtained.
一方、窒化度を低下させることは耐蝕性の低下につなが
ると考えられる。そこで、ＣＯ添加ｆｉｇ。On the other hand, lowering the degree of nitridation is considered to lead to a lowering of corrosion resistance. Therefore, CO addition fig.
１．５．１０．１１％の各試料でＨｃ＝１００００ｅを
有するものについて耐蝕性試験を行なった。A corrosion resistance test was conducted on each sample of 1.5, 10.11% and having Hc=10000e.
試験は、温度６０℃、湿度９０％ＲＨの恒温恒湿槽内に
１０００時１ハ１放置し、放置後の飽和磁化Ｍｓの減少
全測定する方法を採った。比較例及びＣ。The test was carried out by leaving the sample in a constant temperature and humidity chamber at a temperature of 60° C. and a humidity of 90% RH for 1000 hours and measuring the total decrease in saturation magnetization Ms after leaving it. Comparative example and C.
−Ｎｉ系の試料についても同様の方法をとった。A similar method was applied to the -Ni-based sample.
結果を次表に示す。The results are shown in the table below.
表中で、◎はＭｓの低下が３％以内、○は５％以内で十
分実用可能な範囲、△は５〜１０％、×は１０％以上で
、実用上問題があることを示す。In the table, ◎ indicates a decrease in Ms within 3%, ◯ indicates a sufficiently practical range of within 5%, △ indicates a range of 5 to 10%, and × indicates a practical problem of 10% or more.
この表からＣＯ添加量１０％以下では十分な耐蝕性全示
していることがわかる。From this table, it can be seen that when the amount of CO added is 10% or less, sufficient corrosion resistance is exhibited.
＜ト）発明の効果
以上の様に、本発明による磁気記録媒体は、優れた耐蝕
性をもち、また従来の窒化鉄系媒体に比べ高い飽和磁化
を有する。さらに、本発明の磁気記録媒体けＣＯの含有
１が１０９６以下と少ない為、従来例（Ｃｏ−Ｎｉ合金
使用）に比し非常に安価に製造できる。<G) Effects of the Invention As described above, the magnetic recording medium according to the present invention has excellent corrosion resistance and higher saturation magnetization than conventional iron nitride-based media. Furthermore, since the magnetic recording medium of the present invention has a small CO content of 1096 or less, it can be manufactured at a much lower cost than the conventional example (using a Co--Ni alloy).
麻１図は本発明による磁気記録媒体形成装置の概略図、
第２図はＦｅＮ中に添加すべきＣＯＯ量？パラメータと
する磁気記録媒体の飽和磁化対保狐力の関係を示す図で
ある。
ｉｌ＋ フィルムｆｌロー、７、＋３）・・・フィル
ム巻取ローラ、（４）・・・冷却キャン、（７）・・・
蒸着源、（川・・・イオン銃。
出願人 三＃［機徐式会社 １、」１゜代理人 弁理士
西野卓嗣（外１名）
第１図Fig. 1 is a schematic diagram of a magnetic recording medium forming apparatus according to the present invention;
Figure 2 shows the amount of COO that should be added to FeN? FIG. 2 is a diagram showing the relationship between saturation magnetization of a magnetic recording medium and coercive force as parameters. il+ Film fl row, 7, +3)... Film take-up roller, (4)... Cooling can, (7)...
Evaporation source, (river... ion gun. Applicant: 3# [Kiseshiki Company 1,'' 1゜ Agent: Patent attorney Takuji Nishino (1 other person) Figure 1
Claims (3)
成分とする金属薄膜を非磁性基体上に乾式薄膜形成法に
よって形成した磁気記録媒体。(1) A magnetic recording medium in which a metal thin film mainly composed of iron nitride containing 1 to 10 atomic % of cobalt is formed on a nonmagnetic substrate by a dry thin film forming method.
とする特許請求の範囲第１項記載の磁気記録媒体。(2) The magnetic recording medium according to claim 1, wherein the metal thin film is formed by a vapor deposition method.
を特徴とする特許請求の範囲第１項記載の磁気記録媒体
。(3) The magnetic recording medium according to claim 1, wherein the metal thin film is formed by a sputtering method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20498486A JPS6361410A (en) | 1986-08-29 | 1986-08-29 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20498486A JPS6361410A (en) | 1986-08-29 | 1986-08-29 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6361410A true JPS6361410A (en) | 1988-03-17 |
Family
ID=16499545
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20498486A Pending JPS6361410A (en) | 1986-08-29 | 1986-08-29 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6361410A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61110329A (en) * | 1984-11-02 | 1986-05-28 | Hitachi Ltd | Vertical magnetic recording medium |
-
1986
- 1986-08-29 JP JP20498486A patent/JPS6361410A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61110329A (en) * | 1984-11-02 | 1986-05-28 | Hitachi Ltd | Vertical magnetic recording medium |
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