JPH04184710A - Fixed magnetic disk and manufacture thereof - Google Patents
Fixed magnetic disk and manufacture thereofInfo
- Publication number
- JPH04184710A JPH04184710A JP31352290A JP31352290A JPH04184710A JP H04184710 A JPH04184710 A JP H04184710A JP 31352290 A JP31352290 A JP 31352290A JP 31352290 A JP31352290 A JP 31352290A JP H04184710 A JPH04184710 A JP H04184710A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- film
- magnetic disk
- iron oxide
- crystal structure
- 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
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 13
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000010409 thin film Substances 0.000 claims abstract description 43
- 239000000758 substrate Substances 0.000 claims abstract description 22
- 239000013078 crystal Substances 0.000 claims abstract description 21
- 229910052596 spinel Inorganic materials 0.000 claims abstract description 13
- 239000011029 spinel Substances 0.000 claims abstract description 13
- 238000000034 method Methods 0.000 claims abstract description 10
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 9
- 239000010941 cobalt Substances 0.000 claims abstract description 9
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000011701 zinc Substances 0.000 claims description 20
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 18
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 239000011780 sodium chloride Substances 0.000 claims description 6
- 239000007789 gas Substances 0.000 claims description 5
- 239000011572 manganese Substances 0.000 claims description 5
- 150000002902 organometallic compounds Chemical class 0.000 claims 11
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims 3
- 229910052742 iron Inorganic materials 0.000 claims 3
- 229910052725 zinc Inorganic materials 0.000 claims 3
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims 2
- 229910000480 nickel oxide Inorganic materials 0.000 claims 2
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims 1
- 238000005229 chemical vapour deposition Methods 0.000 claims 1
- 229910052748 manganese Inorganic materials 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 claims 1
- 239000002184 metal Substances 0.000 claims 1
- 239000010408 film Substances 0.000 abstract description 55
- 229910000859 α-Fe Inorganic materials 0.000 abstract description 53
- 238000005268 plasma chemical vapour deposition Methods 0.000 abstract description 5
- 229910018605 Ni—Zn Inorganic materials 0.000 abstract description 4
- 239000010410 layer Substances 0.000 description 28
- 238000006243 chemical reaction Methods 0.000 description 13
- 229910000599 Cr alloy Inorganic materials 0.000 description 11
- 229910020630 Co Ni Inorganic materials 0.000 description 9
- 229910002440 Co–Ni Inorganic materials 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 239000006200 vaporizer Substances 0.000 description 8
- 239000012159 carrier gas Substances 0.000 description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 4
- LZKLAOYSENRNKR-LNTINUHCSA-N iron;(z)-4-oxoniumylidenepent-2-en-2-olate Chemical compound [Fe].C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O LZKLAOYSENRNKR-LNTINUHCSA-N 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 239000011241 protective layer Substances 0.000 description 4
- HYZQBNDRDQEWAN-LNTINUHCSA-N (z)-4-hydroxypent-3-en-2-one;manganese(3+) Chemical compound [Mn+3].C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O HYZQBNDRDQEWAN-LNTINUHCSA-N 0.000 description 3
- FJDJVBXSSLDNJB-LNTINUHCSA-N cobalt;(z)-4-hydroxypent-3-en-2-one Chemical compound [Co].C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O FJDJVBXSSLDNJB-LNTINUHCSA-N 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 230000001050 lubricating effect Effects 0.000 description 3
- 238000007747 plating Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- NHXVNEDMKGDNPR-UHFFFAOYSA-N zinc;pentane-2,4-dione Chemical compound [Zn+2].CC(=O)[CH-]C(C)=O.CC(=O)[CH-]C(C)=O NHXVNEDMKGDNPR-UHFFFAOYSA-N 0.000 description 3
- 229910000990 Ni alloy Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000012495 reaction gas Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- SHWZFQPXYGHRKT-FDGPNNRMSA-N (z)-4-hydroxypent-3-en-2-one;nickel Chemical compound [Ni].C\C(O)=C\C(C)=O.C\C(O)=C\C(C)=O SHWZFQPXYGHRKT-FDGPNNRMSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910020676 Co—N Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 229910018104 Ni-P Inorganic materials 0.000 description 1
- 229910018536 Ni—P Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910003481 amorphous carbon Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000004453 electron probe microanalysis Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000000678 plasma activation Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、信顛性に優れ、高密度磁気記録対応を可能に
する固定磁気ディスクおよびその製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fixed magnetic disk that has excellent reliability and is compatible with high-density magnetic recording, and a method for manufacturing the same.
従来の技術
近年の高度情報社会において、記憶すべき情報の量は年
々増加の一途をたどり、記憶装置の大容量化、高密度化
に対する要望も高まっている。2. Description of the Related Art In the recent advanced information society, the amount of information to be stored continues to increase year by year, and the demand for larger capacity and higher density storage devices is also increasing.
このような状況のもと、コンピュータ周辺機器として用
いられる固定磁気ディスクに用いられる記憶媒体は、従
来のアルミディスク基板上にガンマ酸化鉄系の針状磁性
粉などを塗布した塗布型から、めっき法やスパッタ法な
どによるＣｏ−Ｎｉ／ Ｃｒ合金の薄膜型へと変化し、
高密度化が図られてきた。Under these circumstances, the storage media used in fixed magnetic disks used as computer peripherals have changed from the conventional coating type, in which gamma iron oxide acicular magnetic powder is coated on an aluminum disk substrate, to the plating method. It changed to a thin film type of Co-Ni/Cr alloy by sputtering method, etc.
Efforts have been made to increase density.
発明が解決しようとする課題
しかし、Ｃｏ −Ｎ ｉ ／ Ｃｒ合金薄膜型はその構
成材料が合金であるため耐久性などに問題があり、固定
磁気ディスクの構造としては、（潤滑層／保護層／ Ｃ
ｏ −Ｎ ｉ磁性層／Ｃｒ層／ Ｎ ｉ −Ｐめっき層
／アルミニウム基板）の５層構造になっており、製造工
程が複雑であるといった欠点がある。Problems to be Solved by the Invention However, since the Co-Ni/Cr alloy thin film type is composed of an alloy, there are problems with durability, etc.; C
It has a five-layer structure (o-Ni magnetic layer/Cr layer/Ni-P plating layer/aluminum substrate), and has a drawback that the manufacturing process is complicated.
第４図は従来の固定磁気ディスクであるＣｏ−Ｎ ｉ
／ Ｃｒ合金の薄膜型の固定磁気ディスクの断面構造を
示す。図において１はアルミニウム基板、２はＮ１−Ｐ
めっき層、３はＣｒ層、４はＣｏ−Ｎｉ磁性層、５は保
護層、６は潤滑層である。Figure 4 shows a conventional fixed magnetic disk, Co-Ni.
/ Shows the cross-sectional structure of a thin-film type fixed magnetic disk made of Cr alloy. In the figure, 1 is an aluminum substrate, 2 is N1-P
The plating layer 3 is a Cr layer, 4 is a Co-Ni magnetic layer, 5 is a protective layer, and 6 is a lubricating layer.
上記従来の固定磁気ディスクはＣｏ−Ｎ１ｍ性層４が面
内記録媒体であるため、さらに記録密度を上げるために
記録波長を短くしていくと減磁界の影響で記録が困難に
なってくる。Since the above-mentioned conventional fixed magnetic disk has a Co-N1m layer 4 as a longitudinal recording medium, if the recording wavelength is shortened in order to further increase the recording density, recording becomes difficult due to the influence of the demagnetizing field.
そこで、磁気記録方式の上で、上記欠点を改善した記録
方式である垂直記録を可能とする磁気記録媒体として、
磁気ヘッドとその媒体が接触状態となるものではあるが
、Ｃｏ−Ｃｒ１膜媒体などの研究が盛んになされてきた
。しかし第４図に示すＣｏ Ｎｉ／Ｃｒ合金の薄膜型
の記録媒体の場合と同様、Ｃｏ−Ｃｒ１［膜媒体にも合
金であるために信転性に問題があり、Ｃｏ−Ｃｒ１［膜
の表面にアモルファスカーボン膜やＣＯ酸化物のような
保護層５を設けなくてはならないという課題がある。Therefore, as a magnetic recording medium that enables perpendicular recording, which is a recording method that improves the above drawbacks on the magnetic recording method,
Although the magnetic head and its medium are in contact with each other, research has been actively conducted on Co--Cr1 film media. However, as in the case of the Co-Ni/Cr alloy thin-film type recording medium shown in FIG. There is a problem in that a protective layer 5 such as an amorphous carbon film or CO oxide must be provided.
一方、固定磁気ディスク装置において１．磁気ヘッドの
磁気ディスクに対する走行高さ（フライングバイト）を
できるだけ低くすることは、磁気ヘッドと磁気ディスク
スペーシングによる出力の損失（スペーシング損失）を
軽減するため、記録密度向上につながるものであり、最
近では高記録密度を可能にするために、０．０５〜０．
１μｍ程度のフライングハイド量での走行が必要とされ
ている。On the other hand, in a fixed magnetic disk device, 1. Reducing the running height of the magnetic head relative to the magnetic disk (flying bite) as much as possible reduces the output loss (spacing loss) caused by the magnetic head and magnetic disk spacing, which leads to improved recording density. Recently, in order to enable high recording density, 0.05 to 0.
It is required to run with a flying hide amount of about 1 μm.
しかしながら、上記従来のＣｏ−Ｎｉ／Ｃｒ合金の薄膜
型記録媒体、Ｃｏ−ＣｒＷＩ膜型記録媒体いずれにおい
ても、耐久性などに問題があるため、信転性確保のため
薄膜媒体表面に保護層５（数１００人）を形成しなけれ
ばならず、したがってどうしてもスペーシング損失が増
えてしまうという課題が残る。However, both the conventional Co-Ni/Cr alloy thin-film recording medium and the Co-CrWI film-type recording medium have problems with durability, so a protective layer is added to the surface of the thin film medium to ensure reliability. (several 100 people), and the problem remains that the spacing loss inevitably increases.
本発明は上記課題を解決するものであり、信顛性に優れ
、かつ高密度磁気記録対応が可能である垂直磁気記録の
成分を有する固定磁気ディスクとその製造方法を提供す
ることを目的とするものである。The present invention is intended to solve the above problems, and aims to provide a fixed magnetic disk having a perpendicular magnetic recording component that has excellent reliability and is compatible with high-density magnetic recording, and a method for manufacturing the same. It is something.
課題を解決するための手段
上記目的を達成するために本発明は、ディスク基板上に
ＮａＣｌ型結晶構造を有する酸化物薄膜と、その上にス
ピネル型結晶構造の酸化鉄軟磁性膜とさらにその上にコ
バルトを含むスピネル型結晶構造の酸化鉄磁性薄膜を形
成した３層構造の固定磁気ディスクであり、また前記固
定磁気ディスクをプラズマの活性さとＣＶＤ反応を利用
した製造方法により作製するものである。Means for Solving the Problems In order to achieve the above objects, the present invention provides an oxide thin film having an NaCl type crystal structure on a disk substrate, an iron oxide soft magnetic film having a spinel type crystal structure on the thin oxide film, and a soft magnetic film of iron oxide having a spinel type crystal structure on the disk substrate. This is a fixed magnetic disk with a three-layer structure in which an iron oxide magnetic thin film with a spinel-type crystal structure containing cobalt is formed, and the fixed magnetic disk is manufactured by a manufacturing method that utilizes plasma activation and CVD reaction.
作用
したがって本発明によれば、下地層として用いている酸
化物薄膜がＮａＣｌ型結晶構造の（１００）に完全配向
しており、またスピネル型結晶構造の酸化鉄軟磁性薄膜
およびコバルトを含むスピネル型結晶構造の酸化鉄磁性
薄膜も上記酸化物薄膜の配向性の影響を受けて（１００
）の配向性が向上しているため、耐久性や硬度などの信
顛性に優れ、かつ高密度磁気記録ができる。Therefore, according to the present invention, the oxide thin film used as the underlayer is completely oriented in the (100) direction of the NaCl type crystal structure, and the iron oxide soft magnetic thin film has the spinel type crystal structure and the spinel type containing cobalt. The crystalline iron oxide magnetic thin film is also affected by the orientation of the oxide thin film (100
) has improved orientation, so it has excellent reliability such as durability and hardness, and enables high-density magnetic recording.
実施例
以下、本発明の一実施例について図面を参照しながら説
明する。EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例における固定磁気ディスクの
構成を示すものであり、図において７はディスク基板、
８はＮｉＯ膜、９はＭｎ−Ｚｎフェライト膜層、１０は
ＣＯフェライト膜、１１は潤滑層である。FIG. 1 shows the configuration of a fixed magnetic disk in an embodiment of the present invention, and in the figure, 7 is a disk substrate;
8 is a NiO film, 9 is a Mn-Zn ferrite film layer, 10 is a CO ferrite film, and 11 is a lubricating layer.
第２図は本発明の一実施例において固定磁気ディスクの
製造に使用するプラズマＣＶＤ装置の概略図を示すもの
であり、図において１２は反応チャンバー、１３は電極
、１４は反応チャンバー内を低圧に保つための排気系で
、１５は高周波電源（１３，５６ＭＨｚ） 、１６〜２
０は原料の入った気化器で、２１〜２５はキャリアガス
の気化器１６〜２０内への導入の有無を制御するための
第１のバルブ、２６〜３０は原料ガスとキャリアガスの
反応チャンバー１１内への導入の有無を制御するための
第２のバルブ、３１はキャリアガスボンベ（窒素）、３
２は反応ガスボンベ（酸素）、３３は基板回転機構のつ
いた基板加熱ヒーターである。FIG. 2 shows a schematic diagram of a plasma CVD apparatus used for manufacturing a fixed magnetic disk in one embodiment of the present invention. In the figure, 12 is a reaction chamber, 13 is an electrode, and 14 is a device that maintains a low pressure inside the reaction chamber. 15 is a high frequency power supply (13,56MHz), 16-2
0 is a vaporizer containing the raw material, 21 to 25 are first valves for controlling whether or not carrier gas is introduced into the vaporizers 16 to 20, and 26 to 30 are reaction chambers for the raw material gas and carrier gas. a second valve for controlling the presence or absence of introduction into 11; 31 is a carrier gas cylinder (nitrogen);
2 is a reactive gas cylinder (oxygen), and 33 is a substrate heater equipped with a substrate rotation mechanism.
次に本実施例の固定磁気ディスクの製造方法を第２図に
もとづき説明する。Next, the method of manufacturing the fixed magnetic disk of this embodiment will be explained based on FIG.
出発原料として、鉄アセチルアセトナート〔Ｆｅ （Ｃ
５Ｈｔ Ｏｘ ）！ 〕、マンガンアセチルアセトナー
ト［Ｍｎ （Ｃｓ Ｈｙ Ｏｘ ）３ 〕、亜鉛アセチ
ルアセトナート（Ｚｎ （Ｃ５Ｈｔ Ｏｘ ） ｚ
・２Ｈ，０）、にけっるアセチルアセトナート（Ｎｉ（
Ｃｓ Ｈｔ Ｏｘ ）＊ ・ＸＨｚ○〕およびコバル
トアセチルアセトナート（Ｃｏ （Ｃｓ Ｈ，Ｏ□）、
〕を使用し、気化器１６にマンガンアセチルアセトナー
ト、気化器１８に脱水処理を行った亜鉛アセチルアセト
ナート（空気中１００°Ｃで２時間）、気化器１９にコ
バルトアセチルアセトナート、気化器２０に鉄アセチル
アセトナートを入れ、それぞれ１８５℃、１３０°Ｃ１
７０℃、１２０”Ｃ１１３５°Ｃに加熱し保持しておく
。第１のバルブ２１および第２のバルブ２６を開き、窒
素キャリアガス（流量２０５ＣＣＭ）とともにニッケル
アセチルアセチナートの蒸気を、反応ガスとしての酸素
（流量３５ＣＣＭ）とともに排気系１４により減圧され
た反応チャンバー１２内に導入し、プラズマを発生（電
力１．５Ｗ／ｃｄ）させ、４分間減圧下（０，１０Ｔｏ
ｒｒ）で反応を行い、４００℃に加熱したガラス等より
なるディスク基板７ （１２０回転／分）上にＮｉＯ膜
８を成膜し、第１のバルブ２１および第２のバルブ２６
を閉じる。As a starting material, iron acetylacetonate [Fe (C
5HtOx)! ], manganese acetylacetonate [Mn (Cs Hy Ox)3], zinc acetylacetonate (Zn (C5Ht Ox) z
・2H,0), nickel acetylacetonate (Ni(
Cs Ht Ox )* ・XHz○] and cobalt acetylacetonate (Co (Cs H, O□),
), manganese acetylacetonate was placed in the vaporizer 16, dehydrated zinc acetylacetonate (in air at 100°C for 2 hours) was placed in the vaporizer 18, cobalt acetylacetonate was placed in the vaporizer 19, and vaporizer 20 was used. Add iron acetylacetonate to 185°C and 130°C1 respectively.
The temperature is heated to 70°C, 120"C and 1135°C and maintained. The first valve 21 and the second valve 26 are opened and nickel acetylacetinate vapor is introduced as a reaction gas together with nitrogen carrier gas (flow rate 205CCM). Oxygen (flow rate: 35 CCM) is introduced into the reaction chamber 12, which is depressurized by the exhaust system 14, to generate plasma (power: 1.5 W/cd), and then heated under reduced pressure (0.10 To
rr), a NiO film 8 is formed on a disk substrate 7 made of glass or the like heated to 400° C. (120 rotations/min), and a NiO film 8 is formed on the first bulb 21 and the second bulb 26.
Close.
引き続き、真空を破らずに第１のバルブ２２．２３．２
５および第２のバルブ２７．２８．３０を開き、窒素キ
ャリアガス（気化器１７側に流量４ ＳＣＣＭ、気化器
１８側に流量７５ＣＣＭ、気化器２０側に流量１５５Ｃ
ＣＭ ）とともにマンガンアセチルアセトナートの蒸気
と亜鉛アセチルアセトナートの蒸気と鉄アセチルアセト
ナートの蒸気を、反応ガスとしての酸素（流量５ＳＣＣ
Ｍ ）とともに、排気系１４により減圧された反応チャ
ンバー１２内に導入し、プラズマを発生（電力１．５
Ｗ／ｃｉｉ）させ、６分間減圧下（０，０９Ｔｏｒｒ）
で反応を行い、４００℃に加熱したディスク基板７ （
１２０回転／分）上にＭｎ−Ｚｎフェライト膜９を成膜
し、第１のバルブ２２．２３および第２のバルブ２７．
２８を閉じる。Continue to open the first valve 22.23.2 without breaking the vacuum.
5 and second valves 27, 28, and 30, and nitrogen carrier gas (flow rate 4 SCCM to the vaporizer 17 side, flow rate 75 CCM to the vaporizer 18 side, flow rate 155 CCM to the vaporizer 20 side).
CM), manganese acetylacetonate vapor, zinc acetylacetonate vapor, and iron acetylacetonate vapor with oxygen as a reaction gas (flow rate 5 SCC).
M) is introduced into the reaction chamber 12, which is depressurized by the exhaust system 14, to generate plasma (power: 1.5
W/cii) for 6 minutes under reduced pressure (0.09 Torr)
Disk substrate 7 (
A Mn-Zn ferrite film 9 is formed on the first bulb 22.23 and the second bulb 27.
Close 28.
さらに引き続き、真空を破らずに第１のバルブ２４およ
び第２のバルブ２９を開き、窒素キャリアガス（流量７
ＳＣＣＭ）とともにコバルトアセチルアセトナートの蒸
気を鉄アセチルアセトナートの蒸気とともに反応チャン
バー１２内に導入し、プラズマ中（電力１．５Ｗ／ｄ）
で８分間減圧下（０，０７Ｔｏｒｒ）で反応を行い、Ｍ
ｎ −Ｚ ｎフェライト膜９上にＣＯフェライト膜１
０を成膜し、Ｃｏフェライト／Ｍｎ−Ｚｎフェライト／
Ｎ ｉ Ｏの３層膜を形成する。Then, without breaking the vacuum, the first valve 24 and the second valve 29 are opened and the nitrogen carrier gas (flow rate 7
Cobalt acetylacetonate vapor is introduced into the reaction chamber 12 along with iron acetylacetonate vapor (SCCM), and a plasma is generated (power: 1.5 W/d).
The reaction was carried out under reduced pressure (0.07 Torr) for 8 minutes at
CO ferrite film 1 on n-Z n ferrite film 9
Co ferrite/Mn-Zn ferrite/
A three-layer film of N i O is formed.
そして、その３層膜を形成したディスク基板７を反応チ
ャンバー１２から取り出し、裏面にも同様の方法で、同
じ構成の３層膜を形成し、両面に磁性薄膜面をもつＣｏ
フェライト／Ｍｎ Ｚｎフェライトディスク／ Ｎ
ｉ Ｏディスクを作製した。Then, the disk substrate 7 on which the three-layer film was formed was taken out from the reaction chamber 12, and a three-layer film with the same structure was formed on the back side in the same manner.
Ferrite/Mn Zn Ferrite disk/N
An iO disk was prepared.
次に、このディスクを３００℃の空気中で３時間熱処理
を行った後、フッソ系有機物の潤滑剤の入った液槽（図
示せず）に沈めて潤滑層１１を塗布することによって、
固定磁気ディスクを作製した。Next, this disk is heat-treated in air at 300° C. for 3 hours, and then submerged in a liquid tank (not shown) containing a fluorine-based organic lubricant to apply a lubricant layer 11.
A fixed magnetic disk was fabricated.
作製した本実施例の固定磁気ディスクは、ギャップ長（
ＧＬ）が０．２５μｍ、トランク幅（Ｔｗ）が１０μｍ
のＭＩＧヘッドを用いて、５０ｍＡのヘッド電流値を選
んで電磁変換特性の評価を行った。The manufactured fixed magnetic disk of this example had a gap length (
GL) is 0.25μm, trunk width (Tw) is 10μm
The electromagnetic conversion characteristics were evaluated using a MIG head of 50 mA and a head current value of 50 mA.
固定磁気ディスクを３６０Ｏｒ、ｐ、＋ｎの速度で回転
させ、ディスクの中心から２０．０Ｍの円周トラックで
評価を行った。なお、固定磁気ディスクと磁気ヘッドの
相対速度は７．５／ｓｅｃであり、磁気ヘッドのフライ
ングハイドは０．１５μｍであった。A fixed magnetic disk was rotated at a speed of 360 Or, p, +n, and evaluation was performed on a circumferential track of 20.0M from the center of the disk. Note that the relative speed between the fixed magnetic disk and the magnetic head was 7.5/sec, and the flying hide of the magnetic head was 0.15 μm.
次に比較のために、ＨＣ＝ｌＯｋＯｅで、Ｍｓ＝ ８０
０ｅ＋ｎｕ ／ ｃｃのＣｒ層３とＣｏ−Ｎｉ磁性層４
とからなる磁性層膜厚が８００人で、その上に保護層５
としてカーボン膜を６００人形成し、本発明と同様の潤
滑層６を設けた従来のＣｏ −Ｎ ｉ ／ Ｃｒ合金の
薄膜型の固定磁気ディスク（アルミニウム基板で面内方
向に磁化配向したもの）と、ガラスディスク基板上に直
接Ｃｏフェライト磁性膜（作製条件は３層膜の場合と同
じ）を形成した構造のＣｏフェライト薄膜固定磁気ディ
スクを用意し、本実施例の固定磁気ディスクと同じ条件
で電磁変換特性を測定した。Next, for comparison, HC=lOkOe and Ms=80
Cr layer 3 and Co-Ni magnetic layer 4 of 0e+nu/cc
The thickness of the magnetic layer consisting of is 800 mm, and a protective layer 5
A conventional Co-Ni/Cr alloy thin-film type fixed magnetic disk (aluminum substrate with magnetization oriented in the in-plane direction) was prepared by forming 600 carbon films as described above, and provided with a lubricating layer 6 similar to the present invention. A Co ferrite thin film fixed magnetic disk having a structure in which a Co ferrite magnetic film (manufacturing conditions are the same as for the three-layer film) was formed directly on a glass disk substrate was prepared, and electromagnetic treatment was performed under the same conditions as the fixed magnetic disk of this example. The conversion characteristics were measured.
このようにして得られた本実施例の固定磁気ディスクと
従来のＣｏ−Ｎｉ／Ｃｒ合金薄膜固定磁気ディスクおよ
びＣｏフェライト薄膜固定磁気ディスクの再生出力と記
録密度または記録波長との関係を比較して第３図に示す
。The relationship between the reproduction output and recording density or recording wavelength of the thus obtained fixed magnetic disk of this example, a conventional Co-Ni/Cr alloy thin film fixed magnetic disk, and a Co ferrite thin film fixed magnetic disk was compared. It is shown in Figure 3.
第３図において、横軸が記録密度または記録波長で、縦
軸が再生出力である。また、同図中（ａ）が本実施例の
固定磁気ディスク、（ｂ）が比較のための従来のＣｏ−
Ｎｉ／Ｃｒ合金薄膜固定磁気ディスク、（Ｃ）が同じく
他の従来のＣｏフェライト薄膜固定磁気ディスク（Ｃｏ
フェライト単層膜）の特性をそれぞれ示している。In FIG. 3, the horizontal axis represents recording density or recording wavelength, and the vertical axis represents reproduction output. In the figure, (a) is the fixed magnetic disk of this embodiment, and (b) is the conventional Co-magnetic disk for comparison.
The Ni/Cr alloy thin film fixed magnetic disk (C) is the same as another conventional Co ferrite thin film fixed magnetic disk (Co
ferrite single layer film).
第３図から本実施例の固定磁気ディスクは従来のＣｏ
−Ｎ ｉ ／ Ｃｒ合金薄膜固定磁気ディスクやＣｏフ
ェライト薄膜固定磁気ディスクと比較して全体的に再生
出力が高くなっており、高記録密度化対応が可能である
ことがわかる。As shown in Fig. 3, the fixed magnetic disk of this embodiment is different from the conventional Co
It can be seen that the overall reproduction output is higher than that of a -N i /Cr alloy thin film fixed magnetic disk or a Co ferrite thin film fixed magnetic disk, and that it is possible to support higher recording densities.
なお、本実施例の固定磁気ディスクの記録信号の再生波
形をオシロスコープで観察すると、垂直磁気記録成分を
含むことの特徴であるグイパルス波形を示している。Note that when the reproduced waveform of the recording signal of the fixed magnetic disk of this embodiment is observed with an oscilloscope, it shows a gui pulse waveform, which is characterized by including a perpendicular magnetic recording component.
電磁変換特性の測定終了後、本実施例の固定磁気ディス
クを破壊して高分解能の走査型電子顕微鏡（ＳＥＭ）を
用いて、その表面および破断面を観察した結果、その３
層膜は柱状構造を有し、膜厚約４５００人でコラム径は
５００〜９００人であることがわかった。After the measurement of the electromagnetic conversion characteristics, the fixed magnetic disk of this example was broken and its surface and fractured surface were observed using a high-resolution scanning electron microscope (SEM). Part 3
It was found that the layer film had a columnar structure, with a film thickness of about 4500 mm and a column diameter of 500 to 900 mm.
比較のためにガラスディスク基板上に前記実施例と同じ
条件で成膜したＮｉＯ膜およびＭｎ−Ｚｎフェライト膜
およびＣｏフェライト膜を作製し、ＳＥＭにより同様に
観察した結果、ＮｉＯ膜は膜厚が１０００人、Ｍｎ−Ｚ
ｎフェライト膜は膜厚が１５００人、Ｃｏフェライト膜
は膜厚が２０００人であった。For comparison, a NiO film, a Mn-Zn ferrite film, and a Co ferrite film were formed on a glass disk substrate under the same conditions as in the above example, and similarly observed by SEM. As a result, the NiO film had a thickness of 1000 mm person, Mn-Z
The thickness of the n-ferrite film was 1500 mm, and the thickness of the Co ferrite film was 2000 mm.
さらに、電子線マイクロアナライザー（ＥＰＭＡ）によ
りＭｎ−Ｚｎフェライト膜およびＣｏフェライト膜の組
成を分析した結果、それぞれＭｎ／Ｚｎ／Ｆｅ−７／３
／２０、Ｃｏ／Ｆｅ＝１／１９であった。Furthermore, as a result of analyzing the composition of the Mn-Zn ferrite film and Co ferrite film using an electron beam microanalyzer (EPMA), the compositions of the Mn-Zn ferrite film and Co ferrite film were respectively Mn/Zn/Fe-7/3.
/20, Co/Fe=1/19.
次に、Ｍｎ−Ｚｎフェライト膜およびＣＯフェライトＭ
ｌの磁気特性について振動試料型磁気測定装置（ＶＳＭ
）により測定を行った。その結果、Ｍｎ−Ｚｎフェライ
ト膜はＨｃ ＝４５０ｅ、 Ｍｓ＝３２０ｅｍｕ ／ｃ
ｃ、 Ｇ ｏフェライト膜はＨｅ土＝ １．２ＫＯｅ
ＳＭ ｓ ＝２８０ｅｍｕ／ｃｃであった。Next, Mn-Zn ferrite film and CO ferrite M
Vibrating sample magnetometer (VSM)
). As a result, the Mn-Zn ferrite film has Hc = 450e, Ms = 320emu/c
c, Go ferrite film is He soil = 1.2KOe
SM s =280 emu/cc.
また、Ｘ線回折による結晶構造の解析を行った結果、下
地層として用いているＮｉＯ膜はＮａＣｌ型結晶構造の
（１００）に完全配向しており、Ｍｎ−Ｚｎフェライト
膜およびＣｏフェライト膜のいずれの膜も、ＮｉＯ膜の
配向性の影響を受けて下地層を設けない場合と比較して
スピネル型結晶構造における（１００）の配向性は向上
していた。Furthermore, as a result of analyzing the crystal structure by X-ray diffraction, it was found that the NiO film used as the underlayer was completely oriented in the (100) direction of the NaCl type crystal structure, and that both the Mn-Zn ferrite film and the Co ferrite film were completely oriented. The (100) orientation in the spinel crystal structure of the film was also improved compared to the case where no underlayer was provided due to the influence of the orientation of the NiO film.
本実施例の固定磁気ディスクが従来のＣｏ−Ｎ ｉ ／
Ｃｒ合金薄膜磁気ディスクより短波長域の高記録密度
側で再生出力が高い値を示す原因は、垂直磁気記録成分
を含んでいるからであり、またＣｏフェライト薄膜固定
磁気ディスクより高い再生出力を示すのは、下地層とし
て軟磁性材料を用いていることよりＣｏフェライト磁性
層と馬蹄形の磁路を形成することによって反磁界の影響
が低減されているためであると考えられる。The fixed magnetic disk of this embodiment is a conventional Co-N i /
The reason why the reproduction output shows a higher value on the high recording density side in the short wavelength range than the Cr alloy thin film magnetic disk is because it contains a perpendicular magnetic recording component, and it also shows a higher reproduction output than the Co ferrite thin film fixed magnetic disk. This is considered to be because the influence of the demagnetizing field is reduced by forming a horseshoe-shaped magnetic path with the Co ferrite magnetic layer by using a soft magnetic material as the underlayer.
また本発明の他の実施例として同様の成膜方法を用いて
、下地膜にＮｉ−Ｚｎフェライト、Ｍｎフェライト、Ｎ
ｉフェライトまたはＺｎフェライトをそれぞれ成膜し、
Ｃｏフェライト／ Ｎ ｉ −ＺｎフェライトＮｉ０１
Ｃｏフエライト／ Ｍ ｎフェライトＮｉ０１Ｃｏフエ
ライト／ＮｉフエライトＮｉＯまたはＣｏフェライト／
Ｚ ｎフェライトＮｉＯの３層膜ディスクを作製し、
電磁変換特性の評価を行ったその結果、本実施例のＣｏ
フェライト／ Ｍ ｎ −Ｚ ｎフェライトの３層膜よ
りなる固定磁気ディスクの場合と同様に、従来のＣｏ−
Ｎｉ／ Ｃｒ合金薄膜固定磁気ディスクと比較して全体
的に再生出力が高くなった。Further, as another embodiment of the present invention, using the same film forming method, Ni-Zn ferrite, Mn ferrite, N
Forming a film of i-ferrite or Zn-ferrite, respectively,
Co ferrite/Ni-Zn ferrite Ni01
Co ferrite/M n ferrite Ni01Co ferrite/Ni ferrite NiO or Co ferrite/
A three-layer film disk of Zn ferrite NiO was prepared,
As a result of evaluating the electromagnetic conversion characteristics, the Co
As in the case of fixed magnetic disks made of three-layer films of ferrite/Mn-Zn ferrite, conventional Co-
The overall reproduction output was higher than that of a Ni/Cr alloy thin film fixed magnetic disk.
このように上記実施例によれば、ディスク基板上にＮｉ
Ｏ膜８を形成し、その上にＭ ｎ −Ｚ ｎフェライト
膜９を形成し、さらにその上にＣｏフェライト膜１０を
形成しているため、耐久性や硬度などの信転性に優れ、
かつ高密度磁気記録が可能な固定磁気ディスクを製造す
ることができる。In this way, according to the above embodiment, Ni is deposited on the disk substrate.
Since the O film 8 is formed, the Mn-Zn ferrite film 9 is formed on it, and the Co ferrite film 10 is further formed on it, it has excellent reliability such as durability and hardness,
Moreover, a fixed magnetic disk capable of high-density magnetic recording can be manufactured.
発明の効果
本発明は上記実施例より明らかなように、ディスク基板
上に、下地層として（１００）に優先配向したＮｉＯ膜
を形成し、その上にＭｎ−ＺｎフェライトやＮｉ−Ｚｎ
フェライトなどのスピネル型の結晶構造をした酸化鉄軟
磁性薄膜を形成し、さらに磁性層として柱状構造を有す
るＣｏを含むスピネル型酸化鉄磁性薄膜を形成した固定
磁気ディスクの構造であるため、高信頼性であり、かつ
高記録密度対応が可能となるものであり、またその製造
方法にプラズマＣＶＤ法を用いているため、簡単な原料
供給の制御を行うだけで３層膜を簡単に、かつ連続的に
製造できるという利点を有するものである。Effects of the Invention As is clear from the above embodiments, the present invention forms a (100) preferentially oriented NiO film as a base layer on a disk substrate, and then deposits Mn-Zn ferrite or Ni-Zn on top of it.
The fixed magnetic disk has a structure in which a soft magnetic iron oxide film with a spinel-type crystal structure such as ferrite is formed, and a spinel-type iron oxide magnetic thin film containing Co with a columnar structure is formed as the magnetic layer, making it highly reliable. It is highly flexible and can handle high recording densities, and because it uses plasma CVD as its manufacturing method, it can easily and continuously produce a three-layer film by simply controlling the supply of raw materials. It has the advantage of being able to be manufactured in a number of ways.
第１図は本発明の一実施例における固定磁気ディスクの
要部拡大断面図、第２図は同固定磁気ディスクの製造方
法を実施するために使用するプラズマＣＶＤ装置の概略
正面断面図、第３図は実施例および従来例の固定磁気デ
ィスクの記録波長および記録密度と再生出力との関係を
比較して示した特性図、第４図は従来の固定磁気ディス
クの要部拡大断面図である。
７・・・・・・ディスク基板、８・・・・・・ＮｉＯ膜
（酸化物情ＩＩ）、９・・・・・・Ｍ ｎ −Ｚ ｎフ
ェライト膜（酸化鉄軟磁性薄膜）、１０・・・・・・Ｃ
Ｏフェライト膜（コバルトを含むスピネル型結晶構造の
酸化鉄磁性薄膜）。
代理人の氏名 弁理士 小鍜治 明 ほか２名７ −−
− ４ イ ス り 暮 豪８ −−− Ｎｒ
ＯＲ（＃１仁 −１１ｓＲ）９− Ｍｎ−１ｎフズライ
ト順
（＃１仁！！−χ石１刺を淘Ｓ）
箆五図FIG. 1 is an enlarged sectional view of essential parts of a fixed magnetic disk according to an embodiment of the present invention, FIG. 2 is a schematic front sectional view of a plasma CVD apparatus used to carry out the method for manufacturing the fixed magnetic disk, and FIG. The figure is a characteristic diagram comparing the relationship between recording wavelength, recording density, and reproduction output of the fixed magnetic disks of the embodiment and the conventional example, and FIG. 4 is an enlarged sectional view of the main part of the conventional fixed magnetic disk. 7...Disk substrate, 8...NiO film (oxide information II), 9...Mn-Zn ferrite film (iron oxide soft magnetic thin film), 10.・・・・・・C
O ferrite film (iron oxide magnetic thin film with spinel crystal structure containing cobalt). Name of agent: Patent attorney Akira Kokaji and 2 others 7 ---
- 4 Is Riku Australia 8 --- Nr
OR (#1 Ren -11sR) 9- Mn-1n Fuzurite order (#1 Ren!! - χ stone 1 sting S)
Claims (6)
膜を形成し、その酸化物薄膜上にスピネル型結晶構造の
酸化鉄軟磁性薄膜を形成し、さらに前記酸化鉄軟磁性薄
膜上にコバルトを含むスピネル型結晶構造の酸化鉄磁性
薄膜を形成した固定磁気ディスク。(1) Form an oxide thin film with a NaCl type crystal structure on a disk substrate, form an iron oxide soft magnetic thin film with a spinel type crystal structure on the oxide thin film, and further coat cobalt on the iron oxide soft magnetic thin film. A fixed magnetic disk formed with an iron oxide magnetic thin film with a spinel-type crystal structure.
（１００）に優先配向したニッケル酸化物である請求項
（１）記載の固定磁気ディスク。(2) The fixed magnetic disk according to claim 1, wherein the oxide thin film having the NaCl type crystal structure is a nickel oxide crystallographically preferentially oriented in (100).
、マンガン、ニッケルのうち少なくとも一種の元素を含
む請求項（１）記載の固定磁気ディスク。(3) The fixed magnetic disk according to claim (1), wherein the iron oxide soft magnetic thin film having a spinel crystal structure contains at least one element among zinc, manganese, and nickel.
薄膜が、ディスク基板表面に対して垂直方向に柱状構造
を有する請求項（１）記載の固定磁気ディスク。(4) The fixed magnetic disk according to claim 1, wherein the iron oxide magnetic thin film containing cobalt and having a spinel crystal structure has a columnar structure in a direction perpendicular to the surface of the disk substrate.
合ガスをプラズマを用いて反応させ、ディスク基板上に
ＮａＣｌ型結晶構造のニッケル酸化物薄膜を化学蒸着し
、さらに亜鉛を含む有機金属化合物、マンガンを含む有
機金属化合物、ニッケルを含む有機金属化合物のうち少
なくとも一種以上の有機金属化合物の蒸気と、鉄を含む
有機金属化合物の蒸気と酸素との混合ガスをプラズマを
用いて反応させ、前記ニッケル酸化物薄膜上にスピネル
型結晶構造の酸化鉄軟磁性薄膜を形成し、さらに鉄を含
む有機金属化合物の蒸気とコバルトを含む有機金属化合
物の蒸気と酸素の混合ガスをプラズマを用いて分解して
前記酸化鉄軟磁性薄膜上にコバルトを含むスピネル型結
晶構造の酸化鉄磁性薄膜を化学蒸着する固定磁気ディス
クの製造方法。(5) A mixed gas of oxygen and vapor of an organometallic compound containing nickel is reacted using plasma to chemically deposit a nickel oxide thin film with an NaCl type crystal structure on the disk substrate, and an organometallic compound containing zinc, The vapor of at least one organometallic compound containing manganese and the organometallic compound containing nickel is reacted with a mixed gas of the vapor of an organometallic compound containing iron and oxygen using plasma, and the nickel An iron oxide soft magnetic thin film with a spinel-type crystal structure is formed on the oxide thin film, and a mixed gas of oxygen and the vapor of an organometallic compound containing iron and cobalt is decomposed using plasma. A method for manufacturing a fixed magnetic disk, comprising chemical vapor deposition of an iron oxide magnetic thin film having a spinel crystal structure containing cobalt on the iron oxide soft magnetic thin film.
有機金属化合物およびニッケルを含む有機金属化合物お
よび鉄を含む有機金属化合物およびコバルトを含む有機
金属化合物がβ−ジケトン系金属錯体である請求項（５
）に記載の固定磁気ディスクの製造方法。(6) Claim (5) wherein the organometallic compound containing zinc, the organometallic compound containing manganese, the organometallic compound containing nickel, the organometallic compound containing iron, and the organometallic compound containing cobalt are β-diketone metal complexes.
) The method for manufacturing a fixed magnetic disk described in .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2313522A JP2538124B2 (en) | 1990-11-19 | 1990-11-19 | Fixed magnetic disk and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2313522A JP2538124B2 (en) | 1990-11-19 | 1990-11-19 | Fixed magnetic disk and manufacturing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04184710A true JPH04184710A (en) | 1992-07-01 |
| JP2538124B2 JP2538124B2 (en) | 1996-09-25 |
Family
ID=18042327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2313522A Expired - Fee Related JP2538124B2 (en) | 1990-11-19 | 1990-11-19 | Fixed magnetic disk and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2538124B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6020060A (en) * | 1997-09-25 | 2000-02-01 | Fujitsu Limited | Magnetic recording medium, process for producing the same and magnetic disk device |
-
1990
- 1990-11-19 JP JP2313522A patent/JP2538124B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6020060A (en) * | 1997-09-25 | 2000-02-01 | Fujitsu Limited | Magnetic recording medium, process for producing the same and magnetic disk device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2538124B2 (en) | 1996-09-25 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |