JP2799429B2 - Glass material with coercive force - Google Patents

Glass material with coercive force

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Publication number
JP2799429B2
JP2799429B2 JP7240845A JP24084595A JP2799429B2 JP 2799429 B2 JP2799429 B2 JP 2799429B2 JP 7240845 A JP7240845 A JP 7240845A JP 24084595 A JP24084595 A JP 24084595A JP 2799429 B2 JP2799429 B2 JP 2799429B2
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JP
Japan
Prior art keywords
coercive force
fine particles
glass material
silica glass
glass
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
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JP7240845A
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Japanese (ja)
Other versions
JPH0967141A (en
Inventor
智子 赤井
光春 田渕
裕 山中
Original Assignee
工業技術院長
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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F10/00Thin magnetic films, e.g. of one-domain structure
    • H01F10/08Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers
    • H01F10/10Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition
    • H01F10/12Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition being metals or alloys
    • H01F10/13Amorphous metallic alloys, e.g. glassy metals
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C14/00Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix
    • C03C14/004Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix the non-glass component being in the form of particles or flakes
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00Nature of the non-vitreous component
    • C03C2214/30Methods of making the composites

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Ceramic Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Power Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Glass Compositions (AREA)
  • Physical Vapour Deposition (AREA)
  • Thin Magnetic Films (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、保磁力と可視域に
おける透光性とを兼ね備えたガラス材料に関する。
The present invention relates to a glass material having both coercive force and translucency in the visible region.

【0002】[0002]

【従来の技術】磁性体微粒子は、ほぼ単磁区を構成する
数十nm程度の微粒子の状態では、保磁力が著しく増大
する。磁性体微粒子が凝集した粉体については、保磁力
に関する多くの研究例があるが、磁性体微粒子を安定な
マトリックス中に分散させた材料の磁気的性質に関する
研究例は、ほとんどない。
2. Description of the Related Art In the case of magnetic fine particles in the state of fine particles of about several tens of nm constituting substantially a single magnetic domain, the coercive force is significantly increased. There are many examples of research on coercive force with respect to powder in which magnetic fine particles are aggregated, but there are few research examples on magnetic properties of a material in which magnetic fine particles are dispersed in a stable matrix.

【0003】例えば、高い保磁力を有する磁性体微粒子
を可視域で透明なガラス材料に均一に分散させることが
できれば、高い保磁力を有し、且つ透明なガラス材料が
できる可能性がある。
For example, if magnetic fine particles having a high coercive force can be uniformly dispersed in a transparent glass material in the visible region, a transparent glass material having a high coercive force may be produced.

【0004】[0004]

【発明が解決しようとする課題】従って、本発明は、保
磁力と透光性の両方を兼ね備えたガラス材料を提供する
ことを主な目的とする。
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a glass material having both coercive force and translucency.

【0005】[0005]

【課題を解決するための手段】本発明者は、鋭意研究を
重ねた結果、磁性体微粒子形成成分と透明ガラス成分と
を用いて高周波スパッタリング法を行う場合には、高い
保磁力を有し且つ透明なガラス材料が得られることを見
出した。
As a result of intensive studies, the present inventor has found that when a high-frequency sputtering method is performed using a magnetic fine particle forming component and a transparent glass component, a high coercive force is obtained. It has been found that a transparent glass material can be obtained.

【0006】すなわち、本発明は、下記のガラス材料お
よびその製造方法を提供するものである: 1.磁性体微粒子を分散含有しており、高い保磁力を有
し且つ可視域において透光性をもつガラス材料。
That is, the present invention provides the following glass materials and a method for producing the same: A glass material that contains magnetic fine particles in a dispersed manner, has a high coercive force, and has a light-transmitting property in the visible region.

【0007】2.磁性体微粒子がα−Feであり、該微
粒子を分散せしめるガラス材料がシリカガラスである上
記項1に記載のガラス材料。
[0007] 2. Item 2. The glass material according to item 1, wherein the magnetic fine particles are α-Fe, and the glass material in which the fine particles are dispersed is silica glass.

【0008】3.磁性体微粒子形成成分と透明ガラス成
分とを用いて高周波スパッタリング法により磁性体微粒
子を含有する透明ガラス材料を作製する方法。
[0008] 3. A method of producing a transparent glass material containing magnetic fine particles by high frequency sputtering using a magnetic fine particle forming component and a transparent glass component.

【0009】4.磁性体微粒子形成成分が鉄であり、ガ
ラス成分がシリカガラスである上記項3に記載の方法。
4. Item 4. The method according to Item 3, wherein the magnetic fine particle forming component is iron, and the glass component is silica glass.

【0010】5.高周波スパッタリングを行う際のガス
がアルゴンを主成分とする上記項3または4に記載の方
法。
[0010] 5. Item 5. The method according to Item 3 or 4, wherein the gas used for high-frequency sputtering is mainly composed of argon.

【0011】6.上記項3乃至5のいずれかの方法で得
られた磁性体微粒子分散含有する透明ガラスをさらに温
度650〜700℃の範囲で熱処理することを特徴とす
る保磁力を改善した透明ガラス材料。
6. Item 7. A transparent glass material having improved coercive force, wherein the transparent glass containing the magnetic fine particles dispersed therein obtained by any one of the above items 3 to 5 is further heat-treated at a temperature of 650 to 700 ° C.

【0012】[0012]

【発明の実施の形態】本発明のガラス材料における強磁
性体微粒子としては、特に限定されるものではないが、
原料として安価な鉄を使用することにより形成できるα
-Fe微粒子が好ましい。
BEST MODE FOR CARRYING OUT THE INVENTION The ferromagnetic fine particles in the glass material of the present invention are not particularly limited.
Α that can be formed by using inexpensive iron as a raw material
-Fe fine particles are preferred.

【0013】また、可視域において透光性をもつガラス
材料についても、特に限定されるものではないが、例え
ば、シリカガラスがあげられる。本発明において、「可
視域において透光性をもつガラス」とは、可視域でファ
ラデー効果を利用できることを意味する。
The glass material having a light-transmitting property in the visible region is not particularly limited, and examples thereof include silica glass. In the present invention, "glass having translucency in the visible region" means that the Faraday effect can be used in the visible region.

【0014】α−Fe微粒子の粒径は、通常6〜15n
m程度であり、より好ましくは15nm程度である。
The particle size of the α-Fe fine particles is usually 6 to 15 n.
m, more preferably about 15 nm.

【0015】α−Fe微粒子分散シリカガラスの製造方
法としては、アルゴンガスなどの不活性ガス中で高周波
スパッタリング法によって鉄とシリカガラスとを同時ス
パッタして、ガラスなどの基板上にα−Fe含有シリカ
ガラスを析出させる方法が好ましい。例えば、同じ原料
を用いて通常の溶融法によって鉄−シリカガラスを製造
する場合には、Feの大半がイオンとしてガラス中に溶
解するので、α−Fe微粒子は殆ど形成されない。高周
波スパッタリング法は、常法により行うことができ、そ
の条件などは限定されないが、通常10-2torr〜10-3
torr程度の圧力下で数十W〜数百W程度の出力で行う。
As a method for producing α-Fe fine particle-dispersed silica glass, iron and silica glass are simultaneously sputtered by a high-frequency sputtering method in an inert gas such as argon gas, and α-Fe-containing A method of precipitating silica glass is preferred. For example, when iron-silica glass is produced using the same raw material by a normal melting method, most of Fe dissolves in the glass as ions, so that almost no α-Fe fine particles are formed. The high-frequency sputtering method can be performed by a conventional method, and the conditions and the like are not limited, but usually 10 −2 torr to 10 −3.
The operation is performed under a pressure of about torr and an output of about several tens W to several hundred W.

【0016】ここで、SiO2に対するFeの含有割合
をFe/Siモル比で表すと、Fe/Si=15〜20
%程度の領域が好ましく、Fe/Si=20程度がより
好ましい。Feの量が少なすぎる場合には、α−Fe微
粒子が十分に析出いないのに対し、多すぎる場合には、
ガラスの透光性が失われる傾向がある。
Here, when the content ratio of Fe to SiO 2 is represented by a molar ratio of Fe / Si, Fe / Si = 15 to 20
% Is preferable, and Fe / Si = 20 is more preferable. When the amount of Fe is too small, α-Fe fine particles are not sufficiently precipitated, while when it is too large,
The translucency of the glass tends to be lost.

【0017】本発明方法により得られた鉄微粒子分散ガ
ラス材料を空気中で熱処理すると、α−Feがより効率
よくガラス中に析出するので、ガラス材料の保磁力がよ
り一層改善される。熱処理温度は、通常630〜720
℃程度であり、より好ましくは650〜700℃程度で
ある。熱処理温度が低すぎる場合には、鉄微粒子が十分
に成長しないため保磁力が小さくなるのに対し、高すぎ
る場合には、常磁性であるFe23微粒子が析出すると
いう欠点がある。
When the glass material dispersed with iron fine particles obtained by the method of the present invention is heat-treated in the air, α-Fe is more efficiently precipitated in the glass, so that the coercive force of the glass material is further improved. The heat treatment temperature is usually 630 to 720
C., and more preferably about 650-700.degree. When the heat treatment temperature is too low, the coercive force is reduced because the iron fine particles do not grow sufficiently. On the other hand, when the heat treatment temperature is too high, paramagnetic Fe 2 O 3 fine particles are precipitated.

【0018】[0018]

【実施例】以下、本発明を実施例に基づいてさらに詳し
く説明する。
The present invention will be described below in more detail with reference to examples.

【0019】実施例1 雰囲気ガス=Ar、流量=2cc/分、チャンバー内圧
力=10-2torrの条件下にて、Fe/Siモル比が18
%である鉄−シリカガラス混合材料を高周波スパッタリ
ング法によりスパッタして、約1.7nm/分の速度で
約120分間シリカガラス基板上に堆積させた。
Example 1 Under the conditions of an atmosphere gas = Ar, a flow rate = 2 cc / min, and a chamber pressure = 10 −2 torr, the Fe / Si molar ratio was 18
% Of an iron-silica glass mixed material was sputtered by a high frequency sputtering method and deposited on a silica glass substrate at a rate of about 1.7 nm / min for about 120 minutes.

【0020】得られた薄膜材料の組成は、XPSによっ
て目的どおりに調整されていることを確認した。
It was confirmed that the composition of the obtained thin film material was adjusted as intended by XPS.

【0021】次いで、得られた薄膜材料を温度700℃
の空気中で90分間熱処理したところ、図1に示す様に
α−FeによるX線回折ピークが明瞭に観測された。ま
た、この薄膜材料を透過電子顕微鏡により観察したとこ
ろ、該鉄微粒子の平均粒径は15nm程度であることが
確認された。
Next, the obtained thin film material is heated to a temperature of 700 ° C.
As a result, the X-ray diffraction peak due to α-Fe was clearly observed as shown in FIG. When the thin film material was observed with a transmission electron microscope, it was confirmed that the average particle size of the iron fine particles was about 15 nm.

【0022】また、この材料の保磁力を測定したとこ
ろ、図2に示す様に35エルステッドであり、α−Fe
単体の保磁力の30倍以上であることが確認された。
When the coercive force of this material was measured, it was 35 Oe as shown in FIG.
It was confirmed that the coercive force was at least 30 times the coercive force of a single substance.

【0023】実施例2 実施例1と同様なスパッタ条件で得られた薄膜を700
℃大気中で30分熱処理したところ実施例−1と同様に
α−FeのX線回折ピークが明瞭に観測され、保磁力は
30エルステッドと大きな値を示した。
Example 2 A thin film obtained under the same sputtering conditions as in Example 1 was 700
When heat treatment was performed in the air at 30 ° C. for 30 minutes, the X-ray diffraction peak of α-Fe was clearly observed as in Example 1, and the coercive force showed a large value of 30 Oe.

【0024】実施例3 Fe/Siモル比が20%である鉄−シリカガラス混合
材料を使用する以外は実施例1と同様にして膜厚0.6
μmのα−Fe微粒子含有シリカガラス薄膜を得た。
Example 3 A film thickness of 0.6 was obtained in the same manner as in Example 1 except that an iron-silica glass mixed material having an Fe / Si molar ratio of 20% was used.
A μm-containing α-Fe fine particle-containing silica glass thin film was obtained.

【0025】得られた薄膜の製造直後の磁化曲線と大気
中650℃で30分間熱処理した場合の磁化曲線とを図
3に示す。熱処理により、薄膜の磁化の絶対値が著しく
上昇していることが明らかである。
FIG. 3 shows a magnetization curve obtained immediately after the production of the obtained thin film and a magnetization curve obtained by heat-treating at 650 ° C. for 30 minutes in the atmosphere. It is clear that the heat treatment significantly increases the absolute value of the magnetization of the thin film.

【0026】熱処理後の薄膜中には、薄膜X線回折によ
り、粒子径6nm程度のα−Feまたはその固溶体の結
晶が存在することが確認された。
In the thin film after the heat treatment, it was confirmed by thin film X-ray diffraction that crystals of α-Fe or a solid solution thereof having a particle diameter of about 6 nm were present.

【0027】比較例1 Fe/Si比が8%である鉄−シリカガラス混合材料を
実施例1と同様なスパッタ条件でスパッタし、得られた
薄膜材料を650℃で30分熱処理したところα−Fe
による回折ピークは認められず、保磁力も測定不可能な
ほど小さかった。
Comparative Example 1 An iron-silica glass mixed material having an Fe / Si ratio of 8% was sputtered under the same sputtering conditions as in Example 1, and the obtained thin film material was heat-treated at 650 ° C. for 30 minutes. Fe
No diffraction peak was observed, and the coercive force was too small to be measured.

【0028】比較例2 Fe/Si比が21%の組成からなる薄膜材料を実施例
1と同様なスパッタ条件にて作製し、650℃で30分
熱処理したところ、α−Feによる回折が確認された
が、同時にFe2SiO4、Fe23による強いピークも
みられた。また、薄膜はやや金属光沢を帯びており、そ
のため透過率の低下が見られた。
Comparative Example 2 A thin film material having a composition having an Fe / Si ratio of 21% was prepared under the same sputtering conditions as in Example 1 and heat-treated at 650 ° C. for 30 minutes. As a result, diffraction by α-Fe was confirmed. However, at the same time, strong peaks due to Fe 2 SiO 4 and Fe 2 O 3 were also observed. In addition, the thin film had a slightly metallic luster, and a decrease in transmittance was observed.

【0029】[0029]

【発明の効果】本発明によれば、高周波スパッタリング
法を用いることにより、従来にない高い保磁力を有し、
かつ透光性をも兼ね備えたα−Fe微粒子分散ガラスを
容易に得ることができる。
According to the present invention, by using a high frequency sputtering method, a high coercive force, which has not been achieved in the past, is obtained.
Further, it is possible to easily obtain α-Fe fine particle-dispersed glass which also has a light transmitting property.

【0030】本発明による高い保磁力と透明性とを兼ね
備えた新規なガラス材料は、ファラデー効果を利用した
光磁気記録材料などとして有用である。
The novel glass material having both high coercive force and transparency according to the present invention is useful as a magneto-optical recording material utilizing the Faraday effect.

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

【図1】実施例1により得られたα−Fe微粒子分散シ
リカガラス薄膜材料の熱処理後のX線回折結果を示すチ
ャートである。
FIG. 1 is a chart showing the results of X-ray diffraction after heat treatment of a silica glass thin film material with α-Fe fine particles dispersed therein obtained in Example 1.

【図2】実施例1により得られたα−Fe微粒子分散シ
リカガラス薄膜材料の熱処理後の減磁曲線を示すグラフ
である。
FIG. 2 is a graph showing a demagnetization curve after heat treatment of the α-Fe fine particle-dispersed silica glass thin film material obtained in Example 1.

【図3】実施例3で得られた薄膜材料の製造直後の磁化
曲線と大気中650℃で30分間熱処理した場合の磁化
曲線とを示すグラフである。
FIG. 3 is a graph showing a magnetization curve immediately after the production of the thin film material obtained in Example 3 and a magnetization curve when heat-treated at 650 ° C. for 30 minutes in the atmosphere.

───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平5−119362(JP,A) 特開 平4−325423(JP,A) (58)調査した分野(Int.Cl.6,DB名) C03C 14/00 C23C 14/10 H01F 10/28 H01F 41/18────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-119362 (JP, A) JP-A-4-325423 (JP, A) (58) Fields investigated (Int. Cl. 6 , DB name) C03C 14/00 C23C 14/10 H01F 10/28 H01F 41/18

Claims (5)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】鉄−シリカ混合材料を原料として高周波ス
パッタリング法により製造され、シリカガラス中にα−
Fe微粒子を分散含有しており、Si:α−Fe(モル
比):15〜20であり、高い保磁力を有しかつ可視域
において透光性を有するシリカガラス材料。
An iron-silica mixed material is produced by a high frequency sputtering method, and α-
A silica glass material which contains Fe fine particles in a dispersed state and has a Si: α-Fe (molar ratio) of 15 to 20, and has a high coercive force and a light-transmitting property in a visible region.
【請求項2】シリカガラス材料の製造方法において、鉄
−シリカ混合材料をターゲットとする高周波スパッタリ
ング法により、α−Fe微粒子を分散含有しており、S
i:α−Fe(モル比)=15〜20であり、高い保磁
力を有しかつ可視域において透光性を有するシリカガラ
ス材料を製造する方法。
2. A method for producing a silica glass material, wherein α-Fe fine particles are dispersed and contained by a high-frequency sputtering method using an iron-silica mixed material as a target.
i: a method of producing a silica glass material having α-Fe (molar ratio) = 15 to 20, having high coercive force, and having translucency in the visible region.
【請求項3】高周波スパッタリングを行う際のガスがア
ルゴンを主成分とする請求項2に記載の方法。
3. The method according to claim 2, wherein the gas used for high-frequency sputtering mainly comprises argon.
【請求項4】請求項2または3に記載の方法で得られた
α−Fe微粒子を分散含有する透明シリカガラス材料を
さらに温度650〜700℃の範囲で熱処理することを
特徴とする保磁力を改善した透明ガラスの製造方法。
4. A coercive force characterized by further heat-treating the transparent silica glass material containing the α-Fe fine particles obtained by the method according to claim 2 in a temperature range of 650 to 700 ° C. An improved method for producing transparent glass.
【請求項5】請求項4に記載の方法で得られた保磁力を
改善した透明シリカガラス。
5. A transparent silica glass having an improved coercive force obtained by the method according to claim 4.
JP7240845A 1995-08-25 1995-08-25 Glass material with coercive force Expired - Lifetime JP2799429B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7240845A JP2799429B2 (en) 1995-08-25 1995-08-25 Glass material with coercive force

Applications Claiming Priority (1)

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JP7240845A JP2799429B2 (en) 1995-08-25 1995-08-25 Glass material with coercive force

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US6242085B1 (en) 1997-09-17 2001-06-05 Matsushita Electric Industrial Co., Ltd. Magnetic recording medium and method for producing the same

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