JPH0415528B2 - - Google Patents
Info
- Publication number
- JPH0415528B2 JPH0415528B2 JP56107789A JP10778981A JPH0415528B2 JP H0415528 B2 JPH0415528 B2 JP H0415528B2 JP 56107789 A JP56107789 A JP 56107789A JP 10778981 A JP10778981 A JP 10778981A JP H0415528 B2 JPH0415528 B2 JP H0415528B2
- Authority
- JP
- Japan
- Prior art keywords
- film
- magnetic
- foreign matter
- manufacturing
- 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.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 claims description 31
- 239000000758 substrate Substances 0.000 claims description 18
- 238000004519 manufacturing process Methods 0.000 claims description 13
- 238000004544 sputter deposition Methods 0.000 claims description 5
- 238000007740 vapor deposition Methods 0.000 claims description 5
- 239000010408 film Substances 0.000 description 61
- 230000015572 biosynthetic process Effects 0.000 description 20
- 238000005755 formation reaction Methods 0.000 description 20
- 230000007547 defect Effects 0.000 description 12
- 230000000694 effects Effects 0.000 description 5
- 238000005546 reactive sputtering Methods 0.000 description 4
- 239000010409 thin film Substances 0.000 description 4
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910017061 Fe Co Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000013527 degreasing agent Substances 0.000 description 1
- 230000005347 demagnetization Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000010365 information processing Effects 0.000 description 1
- 230000015654 memory Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000005201 scrubbing Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Manufacturing Of Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Description
【発明の詳細な説明】
本発明は磁気デイスク等磁気記録媒体の製造方
法に関し、詳しくは、高密度磁気記録媒体の成膜
工程で発生する磁性膜欠陥をなくし、製造歩留り
を改善した磁気記録媒体の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing magnetic recording media such as magnetic disks, and more specifically to a magnetic recording medium that eliminates magnetic film defects that occur during the film formation process of high-density magnetic recording media and improves manufacturing yield. Relating to a manufacturing method.
情報処理装置のフアイルメモリとして使用され
る磁気デイスク等の記録媒体は、情報量の増加お
よび装置としてのコストパフオーマンスを向上さ
せるため、益々高密度化が要求されると共に高い
信頼性が要求される。 Recording media such as magnetic disks used as file memories in information processing devices are required to have higher density and higher reliability in order to increase the amount of information and improve the cost performance of the device.
高密度記録媒体を実現させるためには、媒体材
料として、磁気的特性（高保磁力化、高磁束密度
化、角型性等）の向上を図ると共に媒体の薄膜化
が必要である。これら要求に対して、従来の塗布
型媒体に代り、薄膜化、磁気的特性の制御が容易
であり、更に耐食性、耐摩耗性に優れた反応スパ
ツタリング等で作成される酸化物連続薄膜磁性媒
体が開発され、高密度記録媒体として良好な特性
が得られている。 In order to realize a high-density recording medium, it is necessary to improve the magnetic properties (higher coercive force, higher magnetic flux density, squareness, etc.) of the medium material and to make the medium thinner. In order to meet these demands, continuous oxide thin film magnetic media made by reactive sputtering etc., which are easy to thin films, control magnetic properties, and have excellent corrosion resistance and abrasion resistance, are replacing conventional coated media. It has been developed and has achieved good characteristics as a high-density recording medium.
しかし、高密度磁気記録媒体は１ビツト当りの
記録面積が微小化し、更に媒体の厚さが0.2μm程
度に極薄化することが必要となり、従つてこれら
媒体を成膜欠陥がなく、安定に製造することは非
常に厳しくなつている。 However, in high-density magnetic recording media, the recording area per bit has become smaller, and the thickness of the medium must also be made extremely thin to about 0.2 μm. Manufacturing is becoming very difficult.
本発明は成膜欠陥の発生原因をくわしく観察し
た結果、見い出されたものであり、以下酸化物連
続薄膜媒体（以下酸化物媒体という）例にとつて
説明する。 The present invention was discovered as a result of detailed observation of the causes of film formation defects, and will be explained below using an example of an oxide continuous thin film medium (hereinafter referred to as oxide medium).
酸化物媒体の成膜工程は、例えば記録材料とし
てFe−Co系合金を用い、真空装置内のチヤンバ
ー（気密室）にアルゴン〔Ar〕と酸素〔Ｏ〕を
含む混合ガスを導入した酸化雰囲気で反応スパツ
タリングを行い、対面に設置されたAl合金基板
にα−Fe2O3、または酸素分圧を調整しFe3O4等
の酸化膜を所定の厚さに形成させ、その後、α−
Fe2O3膜の場合は、水素等の還元雰囲気でFe3O4
膜とし、更に空気中で熱処理し、γ−Fe2O3酸化
膜が第１図の如く形成される。この酸化膜は基板
との密着性も良好である。 The oxide medium film formation process uses, for example, an Fe-Co alloy as the recording material and an oxidizing atmosphere in which a mixed gas containing argon [Ar] and oxygen [O] is introduced into a chamber (airtight chamber) in a vacuum device. Reactive sputtering is performed to form an oxide film such as α-Fe 2 O 3 or Fe 3 O 4 to a predetermined thickness by adjusting the oxygen partial pressure on the Al alloy substrate placed on the opposite side.
In the case of Fe 2 O 3 film, Fe 3 O 4 is removed in a reducing atmosphere such as hydrogen.
A γ-Fe 2 O 3 oxide film is formed as shown in FIG. 1 by heat treatment in air. This oxide film also has good adhesion to the substrate.
この様な成膜工程で作成した酸化物媒体をエラ
ー試験機で試験すると、或る媒体においては、媒
体上の微小部分に欠陥があり記録特性を阻害して
いる。 When oxide media prepared by such a film forming process are tested using an error tester, some of the media have defects in minute portions on the media, which impede recording characteristics.
この原因を詳細に観察すると、基板の平坦性
（基板表面のアラサ、ウネリ等）に基因するもの、
基板の素材の偏析物等に基因するもの、基板
洗浄が不十分であり、磁性膜の密着性が悪く剥離
しているもの、成膜工程でゴミ、ホコリ等異物
が付着し、第２図ａの如く磁性膜厚が減少してい
るものや、または異物の脱落により第２図ｂの如
く磁性膜が剥離しているもの等があり、特に成膜
過程での異物の付着による磁性膜欠陥の依存度が
大きいことがわかつた。 If we look closely at the causes of this, we can see that it is due to the flatness of the substrate (roughness, undulations, etc. on the substrate surface),
Causes include segregation of the substrate material, insufficient substrate cleaning, poor adhesion of the magnetic film and peeling, and foreign matter such as dirt and dust adhering during the film formation process. There are cases where the magnetic film thickness has decreased as shown in Figure 2b, or the magnetic film has peeled off due to foreign matter falling off as shown in Figure 2b. It turns out that there is a great deal of dependence.
成膜工程での異物の付着は、チヤンバー内での
膜形成時において、膜は形成させたい基板のみに
付着するのではなく、基板を保持する治具、ある
いはチヤンバーの内壁などあらゆる部分に付着す
る。これら基板以外に付着した膜は次第に堆積
し、一部ははがれ基板および基板上に形成された
磁性膜上に付着し、成膜後の欠陥を発生させてい
る。従つて、異物付着による成膜欠陥を少なくす
るにはチヤンバー内のあらゆる部分を常に付着物
のない状態に保つことが必要である。しかし、こ
のことは実際上不可能に近く、また仮にこのよう
な環境を得ようとすると長期間、装置の使用を停
止させてしまうもので製造性を著しく低下させて
好ましくない。 When forming a film in a chamber, foreign matter adheres to the film not only to the substrate on which it is to be formed, but also to all parts, such as the jig that holds the substrate or the inner wall of the chamber. . These films deposited on surfaces other than the substrate gradually accumulate, and some of them peel off and adhere to the substrate and the magnetic film formed on the substrate, causing defects after film formation. Therefore, in order to reduce film formation defects due to foreign matter adhesion, it is necessary to keep all parts of the chamber free of deposits at all times. However, this is almost impossible in practice, and even if such an environment were to be obtained, the use of the apparatus would have to be stopped for a long period of time, which would significantly reduce productivity, which is undesirable.
本発明は前記問題点に鑑みなされたものであつ
て、その目的とするところは、異物の付着による
成膜後の欠陥を少なくし、歩留りが良い磁気記録
媒体の製造方法を提供することにある。 The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a method for manufacturing a magnetic recording medium that reduces defects after film formation due to adhesion of foreign matter and has a high yield. .
上記目的達成のため本発明の特徴は、スパツタ
装置あるいは蒸着装置等の成膜装置内に保持され
た基板上に連続する磁気記録用磁性膜を形成する
磁気記録媒体の製造方法において、前記基板上に
磁性膜を形成するための成膜工程を複数回に分割
して行うと共に、複数回に分割された前記成膜工
程の間に、前記磁性膜上に付着した異物を除去す
るための異物除去工程を行うことにある。以下本
発明の実施例を図面を参照して説明する。 To achieve the above object, the present invention is characterized in that a method for manufacturing a magnetic recording medium in which a continuous magnetic film for magnetic recording is formed on a substrate held in a film forming apparatus such as a sputtering apparatus or an evaporation apparatus. The film formation process for forming a magnetic film is performed in multiple steps, and during the film formation process divided into multiple steps, foreign matter removal is performed to remove foreign substances attached to the magnetic film. It lies in carrying out the process. Embodiments of the present invention will be described below with reference to the drawings.
第３図乃至第７図は本発明の磁気記録媒体の製
造方法を工程順に示した断面図である。 FIGS. 3 to 7 are cross-sectional views showing the method for manufacturing a magnetic recording medium of the present invention in the order of steps.
第３図に示す基板１の表面に磁性膜２を所定の
膜厚、例えば2000Åに対し、ｎ分割して成膜す
る。いま、本発明の例として、500Åづつ、４回
に分けて成膜を行う場合について説明する。まず
第３図において、第１回目の成膜を基板１の表面
に膜厚500Åの厚さに磁性膜２を形成する。この
場合、基板に付着していた異物、または成膜工程
中に該磁性膜２の表面に異物３が飛来し付着す
る。 On the surface of the substrate 1 shown in FIG. 3, a magnetic film 2 is formed into n divisions to a predetermined thickness, for example, 2000 Å. Now, as an example of the present invention, a case will be described in which the film is formed in four steps of 500 Å each. First, in FIG. 3, in the first film formation, a magnetic film 2 is formed on the surface of a substrate 1 to a thickness of 500 Å. In this case, foreign matter adhering to the substrate or foreign matter 3 flying and adhering to the surface of the magnetic film 2 during the film forming process.
このように磁性膜２の表面に付着した異物３を
除去工程によつて取り除く。除去工程は高圧ガス
で吹飛ばす方法、回転する基板の一部にスポンジ
や無塵布等を当てて拭きとる方法、更にチヤンバ
ー内より取り出し、スポンジ等を用いて清浄な水
を流しながらこすり洗いする方法、また洗浄液を
用いてデイツプにより洗い落す方法があるが、確
実に除去するためには脱脂剤で脱脂し、次いで純
水で洗浄し、フレオンにデイツプして異物を除去
し、最後にフレオン蒸気により洗浄し乾燥する方
法が行なわれる。 The foreign matter 3 adhering to the surface of the magnetic film 2 in this way is removed by a removal process. The removal process involves blowing it away with high-pressure gas, wiping it with a sponge or dust-free cloth, etc. on a part of the rotating board, and then removing it from the chamber and scrubbing it with clean water using a sponge, etc. There is also a method of washing with a dip using a cleaning solution, but in order to ensure removal, degrease with a degreaser, then wash with pure water, dip in Freon to remove foreign substances, and finally use Freon steam. A method of washing and drying is performed.
第４図は前記除去工程により異物を除去した断
面で異物を除去したあとに凹み４が生ずる。しか
し、このような異物を除去して生じた凹み４は次
の成膜工程で次第に馴らされ殆んど影響のない状
態となる。 FIG. 4 shows a cross section where foreign matter has been removed by the above-mentioned removal process, and a depression 4 is formed after the foreign matter has been removed. However, the depressions 4 created by removing such foreign matter are gradually smoothed out in the next film forming process and become almost unaffected.
第５図は前記第１回目の成膜、異物除去工程を
経た磁性膜上に第２回目の成膜２′を施した断面
図で第１回目に成膜した上面に再度500Åの膜が
形成される。この場合においても前述の膜形成時
と同様異物３′が付着する事が考えられる。 Figure 5 is a cross-sectional view of the second film 2' formed on the magnetic film that has undergone the first film formation and foreign matter removal process, and a 500 Å film is again formed on the top surface where the first film was formed. be done. In this case as well, it is conceivable that foreign matter 3' may adhere as in the case of film formation described above.
第６図は前述第５図の磁性膜２′上に付着した
異物３′を前述除去方法と同様にして異物３′を除
去した図で凹み４′を示している。 FIG. 6 shows a recess 4' in which the foreign matter 3' attached to the magnetic film 2' of FIG. 5 has been removed in the same manner as the above-mentioned removal method.
このようにして第３図，第４図とそれぞれ500
Åづつの磁性膜を形成することにより第７図に示
す如く４層の磁性膜２，２′，２″，２によつて
所定膜厚2000Åの磁性膜が形成される。なお、磁
性膜の分割数は多い程その効果が大きいことは当
然であるが製造性が低下するため可及的、分割数
が少ない方が好ましい。しかし、分割数を多くす
ると、１回当りの成膜される磁性膜が薄くなり、
このため成膜時に発生する基板の温度上昇が低く
なるため成膜時の電力を上げ成膜速度を早める利
点はある。 In this way, Figure 3 and Figure 4 each have 500
As shown in FIG. 7, by forming a magnetic film with a thickness of 2000 Å, a magnetic film with a predetermined thickness of 2000 Å is formed by four layers of magnetic films 2, 2', 2'', and 2, as shown in FIG. It goes without saying that the larger the number of divisions, the greater the effect, but since it reduces manufacturability, it is preferable to have as few divisions as possible.However, if the number of divisions is increased, the magnetic The membrane becomes thinner,
Therefore, the temperature rise of the substrate that occurs during film formation is reduced, so there is an advantage that the power during film formation can be increased and the film formation speed can be accelerated.
第８図は本発明製法により得られた磁気記録媒
体の効果を示したもので従来の単層膜と比較し
た。即ち、この場合は３層に分割し、成膜した場
合をエラー試験機で磁性膜欠陥を試験したもの
で、平均再生出力電圧を100とし、スライスレベ
ルを変えた時の媒体一面当りの磁性膜の欠陥数
（ミツシングエラー数）と、直流消磁後の再生出
力電圧を０とし、それ以上に発生するパルスをス
ライスレベルを変え、面当りの欠陥数（エキスト
ラエラー数）とし示したもので、前者は主に膜厚
変動に依存し、後者は凹み、ピンホール等に主に
依存するものである。 FIG. 8 shows the effect of the magnetic recording medium obtained by the manufacturing method of the present invention, and is compared with a conventional single layer film. That is, in this case, the magnetic film defects were tested using an error tester when the film was divided into three layers and the average reproduction output voltage was set to 100, and the slice level was changed. The number of defects per surface (number of missing errors) and the number of defects per surface (number of extra errors) are shown by setting the reproduction output voltage after DC demagnetization to 0 and changing the slice level for pulses generated above that value. The former mainly depends on film thickness variations, and the latter mainly depends on dents, pinholes, etc.
同図から明らかなように本発明により磁性膜の
欠陥は大幅に減少し、その効果が大であることが
わかる。なお、前記説明は反応スパツタリングで
形成される酸化物媒体が成膜工程を分割し、その
間に異物除去工程を介挿することで行つたが、こ
れらの応用は、気密槽（チヤンバー）内で行なわ
れる他の薄膜形成法、例えば蒸着、イオンブレー
テング、CVD法等についても、また金属磁性媒
体についても、本目的と同じであれば同様方法で
行なうことができる。 As is clear from the figure, defects in the magnetic film are significantly reduced by the present invention, and the effect is significant. In the above explanation, the oxide medium formed by reactive sputtering divides the film formation process and a foreign matter removal process is inserted between them, but these applications are performed in an airtight chamber. The same method can be used for other thin film forming methods, such as vapor deposition, ion blating, and CVD methods, as well as for metal magnetic media, if the purpose is the same as the present invention.
以上説明したように本発明の成膜工程を複数回
に分割すること、更にはまたそれらの間に異物除
去を行なう工程を介挿することによつて磁性膜に
付着した異物を除去し、磁性膜欠陥を減少させ、
磁気記録媒体の製造時における歩留りを大幅に向
上することができ、その効果は極めて大である。 As explained above, by dividing the film-forming process of the present invention into multiple steps and further interposing a process for removing foreign matter between them, foreign matter attached to the magnetic film can be removed and the magnetic reduce membrane defects,
The yield during manufacturing of magnetic recording media can be greatly improved, and the effect is extremely large.
第１図は従来の反応スパツタリングで形成され
た単層膜の媒体を示す断面図、第２図ａおよびｂ
は磁性膜に異物が付着し、磁性膜欠陥となること
を示した従来の媒体の断面図、第３図乃至第７図
は本発明の磁気記録媒体の製造方法を工程順に示
す断面図、第３図は１回目の成膜による異物付着
を示す断面図、第４図は第３図に示す異物を除去
工程により取り除いた後の断面図、第５図は２回
目の成膜と異物付着を示す断面図、第６図は第５
図の異物を除去工程により取り除いた後の断面
図、第７図は最終４回の成膜後の断面図を示す図
である。また第８図は本発明の効果を説明するた
めの媒体と同一条件で試験した試験結果を示すグ
ラフである。
図において、１は基板、２，２′，２″，２は
磁性膜、３，３′，３″，３は成膜時に付着した
異物、４，４′，４″，４は異物を除去して生じ
た凹みを示す。
Figure 1 is a cross-sectional view of a single-layer media formed by conventional reactive sputtering; Figures 2a and b;
3 is a cross-sectional view of a conventional medium showing that foreign matter adheres to the magnetic film, resulting in magnetic film defects; FIGS. Figure 3 is a cross-sectional view showing foreign matter adhesion during the first film formation, Figure 4 is a cross-sectional view after the foreign matter shown in Figure 3 has been removed in the removal process, and Figure 5 is a cross-sectional view showing the second film formation and foreign matter adhesion. The sectional view shown in FIG.
FIG. 7 is a cross-sectional view after removing the foreign matter in the removal process, and FIG. 7 is a cross-sectional view after the final four film formations. Further, FIG. 8 is a graph showing the test results of a test conducted under the same conditions as the medium for explaining the effects of the present invention. In the figure, 1 is the substrate, 2, 2', 2'', 2 is the magnetic film, 3, 3', 3'', 3 is foreign matter attached during film formation, 4, 4', 4'', 4 is foreign matter removed This shows the dent caused by the process.
Claims (1)
れた基板上に連続する磁気記録用磁性膜を形成す
る磁気記録媒体の製造方法において、 前記基板上に磁性膜を形成するためのスパツタ
リング工程あるいは蒸着工程を複数回に分割して
行うと共に、 複数回に分割された前記スパツタリング工程あ
るいは蒸着工程の間に、前記磁性膜上に付着した
異物を除去するための異物除去工程を行うこと を特徴とする磁気記録媒体の製造方法。 ２ 特許請求の範囲第１項記載の磁気記録媒体の
製造方法において、上記異物除去工程は、上記ス
パツタリングあるいは蒸着を行う装置内に設置さ
れた異物除去手段により行われることを特徴とす
る磁気記録媒体の製造方法。[Scope of Claims] 1. A method for manufacturing a magnetic recording medium in which a continuous magnetic film for magnetic recording is formed on a substrate held in a sputtering device, a vapor deposition device, etc., comprising: A sputtering step or a vapor deposition step is performed in multiple steps, and a foreign matter removal step is performed to remove foreign objects attached to the magnetic film between the plurality of divided sputtering steps or vapor deposition steps. A method of manufacturing a magnetic recording medium characterized by: 2. The method for manufacturing a magnetic recording medium according to claim 1, wherein the foreign matter removing step is performed by a foreign matter removing means installed in the sputtering or vapor deposition apparatus. manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10778981A JPS589221A (en) | 1981-07-10 | 1981-07-10 | Manufacture of magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10778981A JPS589221A (en) | 1981-07-10 | 1981-07-10 | Manufacture of magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS589221A JPS589221A (en) | 1983-01-19 |
| JPH0415528B2 true JPH0415528B2 (en) | 1992-03-18 |
Family
ID=14468064
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10778981A Granted JPS589221A (en) | 1981-07-10 | 1981-07-10 | Manufacture of magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS589221A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59140630A (en) * | 1983-02-01 | 1984-08-13 | Anelva Corp | Manufacturing device of magnetic recording medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5155995A (en) * | 1974-11-12 | 1976-05-17 | Nippon Telegraph & Telephone | Sankabutsujiseihakumakuno seizohoho |
| JPS5360205A (en) * | 1976-11-10 | 1978-05-30 | Matsushita Electric Ind Co Ltd | Magnetic recording medium and its manufacture |
| JPS5680832A (en) * | 1979-12-04 | 1981-07-02 | Fujitsu Ltd | Disk transfer device |
-
1981
- 1981-07-10 JP JP10778981A patent/JPS589221A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5155995A (en) * | 1974-11-12 | 1976-05-17 | Nippon Telegraph & Telephone | Sankabutsujiseihakumakuno seizohoho |
| JPS5360205A (en) * | 1976-11-10 | 1978-05-30 | Matsushita Electric Ind Co Ltd | Magnetic recording medium and its manufacture |
| JPS5680832A (en) * | 1979-12-04 | 1981-07-02 | Fujitsu Ltd | Disk transfer device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS589221A (en) | 1983-01-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7166318B2 (en) | Production method and production apparatus for magnetic recording medium | |
| US6565719B1 (en) | Magnetic disk comprising a first carbon overcoat having a high SP3 content and a second carbon overcoat having a low SP3 content | |
| KR100418640B1 (en) | Magnetic recording medium and its manufacturing method | |
| US6521286B2 (en) | Method for manufacturing a magnetic recording medium | |
| JPH0777019B2 (en) | Substrate for magnetic recording medium and manufacturing method thereof | |
| US6103300A (en) | Method for manufacturing a recording medium having metal substrate surface | |
| JPH0415528B2 (en) | ||
| US5690838A (en) | Magnetic recording medium and process for producing same | |
| JPH0490125A (en) | Magnetic recording medium and its production | |
| JP3081070B2 (en) | Manufacturing method of small-diameter magnetic disk | |
| JP2802213B2 (en) | Method and apparatus for manufacturing magnetic recording medium | |
| JP2011243254A (en) | Manufacturing method of magnetic recording medium and manufacturing device of magnetic recording medium | |
| JPH11250455A (en) | Magnetic disk manufacturing method | |
| WO1999045537A1 (en) | Magnetic recording medium, process for fabricating the same, and magnetic storage apparatus made by using the same | |
| JP3198165B2 (en) | Manufacturing method of magnetic recording medium | |
| JPH0442437A (en) | Device and method for manufacturing magnetic disk | |
| JPH01251313A (en) | Magnetic recording medium | |
| JP2000057563A (en) | Manufacture of magnetic recording medium | |
| JPH10112023A (en) | Magnetic disk inspection method | |
| JPH1021537A (en) | Production of magnetic recording medium | |
| JPH05120664A (en) | Magnetic disk and production of the same | |
| JPH05314468A (en) | Magnetic recording medium and manufacture of the same | |
| JPH0316024A (en) | Production of magnetic disk | |
| JPH01182925A (en) | Production of magnetic recording medium | |
| JPH0461625A (en) | Magnetic disk consisting of glass |