JPH0196823A - Production of magnetic recording medium - Google Patents
Production of magnetic recording mediumInfo
- Publication number
- JPH0196823A JPH0196823A JP25254187A JP25254187A JPH0196823A JP H0196823 A JPH0196823 A JP H0196823A JP 25254187 A JP25254187 A JP 25254187A JP 25254187 A JP25254187 A JP 25254187A JP H0196823 A JPH0196823 A JP H0196823A
- Authority
- JP
- Japan
- Prior art keywords
- vapor
- film
- magnetic recording
- recording medium
- 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 description 48
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 150000002500 ions Chemical class 0.000 claims abstract description 14
- 239000000758 substrate Substances 0.000 claims abstract description 14
- 238000007740 vapor deposition Methods 0.000 claims abstract description 13
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 7
- 238000001771 vacuum deposition Methods 0.000 claims abstract description 4
- -1 polyethylene terephthalate Polymers 0.000 claims abstract description 3
- 238000000151 deposition Methods 0.000 claims description 6
- 230000008021 deposition Effects 0.000 claims description 5
- 230000001678 irradiating effect Effects 0.000 claims description 3
- 239000011261 inert gas Substances 0.000 claims description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims 5
- 239000011651 chromium Substances 0.000 claims 5
- 229910017052 cobalt Inorganic materials 0.000 claims 5
- 239000010941 cobalt Substances 0.000 claims 5
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N argon Substances [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims 1
- 229910052786 argon Inorganic materials 0.000 claims 1
- 229910000599 Cr alloy Inorganic materials 0.000 abstract description 8
- 239000013078 crystal Substances 0.000 abstract description 8
- 238000010894 electron beam technology Methods 0.000 abstract description 3
- 229920000139 polyethylene terephthalate Polymers 0.000 abstract description 2
- 239000005020 polyethylene terephthalate Substances 0.000 abstract description 2
- 238000001704 evaporation Methods 0.000 description 7
- 230000008020 evaporation Effects 0.000 description 7
- 238000007738 vacuum evaporation Methods 0.000 description 5
- 230000005415 magnetization Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 229910000889 permalloy Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Physical Vapour Deposition (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〕
本発明は磁気記録媒体に係り、さらに詳しくは垂直磁気
特性に優れた磁性層を有する磁気記Rjjt:体の製造
方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording medium, and more particularly to a method for manufacturing a magnetic recording medium having a magnetic layer having excellent perpendicular magnetic properties.
近年、磁気記録の高密度化に伴ない、磁気記録媒体の膜
面に対して垂直方向に磁化して記録再生を行う垂直磁気
記録方式の研究開発が活発に行われている。In recent years, as the density of magnetic recording has increased, research and development have been actively conducted on perpendicular magnetic recording systems in which recording and reproduction are performed by magnetizing perpendicularly to the film surface of a magnetic recording medium.
垂直磁気記録方式に関して、さらにその性能を高めるた
めに、パーマロイなどの軟磁性層上に、磁気記録媒体の
膜面垂直方向に磁化容易軸を有するGo−Cr合金など
よりなる硬磁性層を、真空蒸着法またはスパッタリング
法などの成膜法により順次積層した2層構造の垂直磁気
記録媒体が提案されている〔アイ・イー・イー・イー、
トランザクションオンマグネチックス、エムエージ−1
5、6(1979年11月)第1456頁から第145
8頁(TE E E 、 Trans、、 Magne
tics、 MAG15.6(Nov、、 1979)
pp 1456〜1458) L (アイ・イー・イ
ー・イー、トランザクションオンマグネチックス、エム
エージ−20,1(1984年1月)第99頁から第1
01頁(I E E E 、 Trans、 、 Ma
gnetics。Regarding the perpendicular magnetic recording system, in order to further improve its performance, a hard magnetic layer made of a Go-Cr alloy or the like having an axis of easy magnetization perpendicular to the film surface of the magnetic recording medium is placed on a soft magnetic layer such as permalloy in a vacuum. A perpendicular magnetic recording medium with a two-layer structure in which layers are sequentially stacked using a film forming method such as vapor deposition or sputtering has been proposed [I.E.E.
Transaction on Magnetics, MG-1
5, 6 (November 1979) pp. 1456-145
8 pages (TEEE, Trans, Magne
tics, MAG15.6 (Nov, 1979)
pp 1456-1458) L (I.E.I., Transactions on Magnetics, MG-20, 1 (January 1984), pp. 99-1
Page 01 (IEEE, Trans, , Ma
genetics.
MAG20.1 (Jan、、 1984) pp 9
9〜101) )。MAG20.1 (Jan, 1984) pp 9
9-101) ).
このような2層構造の磁気記録媒体は、記録再生時にお
ける感度は向上するものの、パーマロイなどの軟磁性層
上に形成されたCo−Cr合金などからなる垂直磁化膜
の結晶配向性が大きく乱され、特にCo−Cr垂直磁化
膜の膜厚が薄いと十分な磁気特性を保持することができ
ないという問題があった。この問題を解消するために、
軟磁性層としてCo膜あるいは非磁性のCo−Cr合金
膜などを用いることが試みられているが、いまだ磁気特
性を充分に満足させる垂直磁気記録媒体を得ることがで
きなかった。Although such a two-layer magnetic recording medium improves sensitivity during recording and reproduction, the crystal orientation of the perpendicularly magnetized film made of a Co-Cr alloy or the like formed on a soft magnetic layer such as permalloy is greatly disturbed. In particular, if the Co--Cr perpendicularly magnetized film is thin, sufficient magnetic properties cannot be maintained. To solve this problem,
Although attempts have been made to use a Co film or a nonmagnetic Co--Cr alloy film as the soft magnetic layer, it has not yet been possible to obtain a perpendicular magnetic recording medium that satisfies the magnetic properties.
上述したごとく、従来技術におけるパーマロイなどの軟
磁性層とGo−Cr合金などの硬磁性層よりなる2N構
造の垂直磁気記録媒体においては、軟磁性層上に形成さ
れるG o −Cr垂直磁化膜の結晶配向性が乱され、
そのため垂直磁気特性が低下するという問題があった。As mentioned above, in the conventional perpendicular magnetic recording medium with a 2N structure consisting of a soft magnetic layer such as permalloy and a hard magnetic layer such as Go-Cr alloy, a Go-Cr perpendicular magnetization film formed on the soft magnetic layer is used. The crystal orientation of is disturbed,
Therefore, there was a problem in that the perpendicular magnetic properties deteriorated.
本発明の目的は、上記従来技術の問題点を解消し、真空
蒸着法によって、垂直磁気特性に優れたC o −Cr
垂直磁化膜を有する磁気記録媒体を製造する方法を提供
することにある。An object of the present invention is to solve the problems of the prior art described above, and to produce Co-Cr with excellent perpendicular magnetic properties by a vacuum evaporation method.
An object of the present invention is to provide a method for manufacturing a magnetic recording medium having a perpendicularly magnetized film.
本発明者らは1種々研究を重ねた結果、基板上にGo−
Cr合金を真空蒸着法によって成膜する際、CoとCr
の蒸気をイオン化するか、または上記蒸気流に不活性ガ
スのイオンを照射すると、形成されるCo−Cr垂直磁
化膜の結晶配向性が向上し保磁力が低下することを見い
出した。As a result of various researches, the present inventors have found that Go-
When forming a Cr alloy film by vacuum evaporation method, Co and Cr
It has been found that by ionizing the vapor or irradiating the vapor flow with inert gas ions, the crystal orientation of the Co--Cr perpendicularly magnetized film to be formed is improved and the coercive force is reduced.
すなわち、上記本発明の目的は、基板上にG。That is, the object of the present invention is to provide G on a substrate.
−Crの垂直磁化膜を真空蒸着法によって形成させる場
合において、蒸着の初期に、GoとCrの蒸気の一部ま
たは全部を高周波電極などによってイオン化するか、ま
たはイオン銃などによってArなどの不活性ガスのイオ
ンをCoとCrの蒸気流に照射して、イオンを含む蒸気
流として蒸着を行い、まず基板上に低保磁力を有するG
o−Cr膜を蒸着し、その上にCo−Cr垂直磁化膜を
形成させることによって、下層部で低保磁力、上層部で
高保磁力を有し、かつ下層部から上層部にかけて極めて
結晶配向性が良好で垂直磁気特性に優れたGo−Cr垂
直磁化膜を成膜することにより、達成される。- When forming a perpendicularly magnetized Cr film by vacuum evaporation, some or all of the Go and Cr vapors are ionized using a high-frequency electrode, or an inert film such as Ar is ionized using an ion gun, etc., at the beginning of the evaporation process. Gas ions are irradiated into a Co and Cr vapor stream to deposit the ion-containing vapor stream onto the substrate.
By depositing an o-Cr film and forming a Co-Cr perpendicular magnetization film on it, the lower layer has a low coercive force and the upper layer has a high coercive force, and the crystal orientation is extremely high from the lower layer to the upper layer. This is achieved by forming a Go-Cr perpendicularly magnetized film with good perpendicular magnetic properties.
本発明の方法によって製造される磁気記録媒体は、ポリ
エチレンテレフタレート、ポリエステル、ポリイミド、
ポリアミド、ポリ塩化ビニルなどの合成樹脂製のフィル
ムあるいはAQ 、AQ合金。The magnetic recording medium manufactured by the method of the present invention can be made of polyethylene terephthalate, polyester, polyimide,
Films made of synthetic resins such as polyamide and polyvinyl chloride, or AQ and AQ alloys.
Ti、Ti合金、ステンレスなどの金属板などを基体と
するテープ、シート、カード、ディスク状などの種々の
形態の磁気記録媒体を包含するものである。It includes various forms of magnetic recording media such as tapes, sheets, cards, disks, etc., which are based on metal plates such as Ti, Ti alloys, and stainless steel.
以下に本発明の一実施例を挙げ図面を参照しながらさら
に詳細に説明する。Hereinafter, one embodiment of the present invention will be described in more detail with reference to the drawings.
(実施例1)
第1図に示す構造の真空蒸着装置を用い垂直磁気記録媒
体を作製した。図において、基板1はヒータ2によって
蒸着を行う前に150℃の温度に加熱されている。蒸発
源3に装填されているG o −10wt%Cr合金は
、電子銃4からの電子線により加熱蒸発され、基板1上
に膜厚が500人になるまで高周波電極5により蒸着蒸
気をイオン化し、蒸着速度を20人/秒として蒸着した
。この時、印加した高周波電力は300Wである。つい
で、高周波電力の印加を停止して、蒸着速度20人/秒
で、合計膜厚が2500人のGo−19wt%Crから
なる垂直磁化膜を形成させて磁気ディスクを作製した。(Example 1) A perpendicular magnetic recording medium was manufactured using a vacuum evaporation apparatus having the structure shown in FIG. In the figure, a substrate 1 is heated to a temperature of 150° C. by a heater 2 before performing vapor deposition. The Go-10wt%Cr alloy loaded in the evaporation source 3 is heated and evaporated by the electron beam from the electron gun 4, and the evaporated vapor is ionized by the high frequency electrode 5 until the film thickness reaches 500 nm on the substrate 1. , and the deposition rate was 20 people/second. At this time, the high frequency power applied was 300W. Then, the application of high frequency power was stopped, and a perpendicularly magnetized film made of Go-19 wt % Cr having a total film thickness of 2,500 layers was formed at a deposition rate of 20 layers/second to produce a magnetic disk.
(実施例2)
第2図に示す構造の真空蒸着装置を用い垂直磁気記録媒
体を作製した。図において、基板1は供給ロール9から
回転ドラム10を介して巻取ロール11に巻取られる。(Example 2) A perpendicular magnetic recording medium was manufactured using a vacuum evaporation apparatus having the structure shown in FIG. In the figure, a substrate 1 is wound up from a supply roll 9 via a rotating drum 10 onto a take-up roll 11 .
回転ドラム10は内部に設けられているヒータにより2
50℃に加熱されている。蒸発源12に装填されている
Coおよび蒸発源13に装填されているCrは、電子銃
4によって電子線加熱により蒸発させ、成膜速度を30
0人/秒として。The rotating drum 10 is heated by a heater provided inside.
It is heated to 50°C. Co loaded in the evaporation source 12 and Cr loaded in the evaporation source 13 are evaporated by electron beam heating by the electron gun 4, and the film formation rate is increased to 30%.
As 0 people/second.
基板1上に膜厚が2500人のG o−19w t%C
rよりなる垂直磁化膜を形成させた。この時、基板1上
に蒸着される蒸気の初期入射部に設けられているイオン
銃14からArイオンを照射しながら成膜した。Arイ
オンの加速電圧は1 kV、電流は30mAであった。Go-19wt%C with a film thickness of 2500 on substrate 1
A perpendicularly magnetized film made of r was formed. At this time, the film was formed while irradiating Ar ions from the ion gun 14 provided at the initial incidence part of the vapor to be deposited on the substrate 1. The Ar ion acceleration voltage was 1 kV and the current was 30 mA.
(比較例1)
蒸着初期に高周波電極5による蒸着用蒸気のイオン化を
行わない他は、実施例1と同様にしてG o −Cr垂
直磁化膜を形成させ磁気記録媒体を作成した。(Comparative Example 1) A magnetic recording medium was produced by forming a G o -Cr perpendicularly magnetized film in the same manner as in Example 1, except that the vapor for vapor deposition was not ionized by the high-frequency electrode 5 at the initial stage of vapor deposition.
(比較例2)
蒸着初期に高周波電極5によって蒸着用蒸気のイオン化
を行いつつ蒸着した厚さ500人のG o −Cr合金
膜の代りに、厚さSOO人のGo(純度99,9%)を
蒸着した他は、実施例1と同様にしてG。(Comparative Example 2) Instead of a 500-thick Go-Cr alloy film, which was deposited while ionizing the vapor for evaporation using the high-frequency electrode 5 in the early stage of vapor deposition, a SOO-thick Go (purity of 99.9%) was used. G was deposited in the same manner as in Example 1, except that G was vapor-deposited.
からなる垂直磁化膜を形成させ磁気記録媒体を作製した
。A magnetic recording medium was fabricated by forming a perpendicularly magnetized film consisting of:
上記の実施例および比較例において作製した磁気記録媒
体について、Co−Cr垂直磁化膜の結晶配向性(X線
回折のC軸の分散Δθ20 )と垂直磁気特性〔膜面垂
直方向に測定した初期蒸着膜(500人)の保磁力He
上および成膜した垂直磁化膜の保磁力Hcl)を調べた
。その結果を第1表に示す。Regarding the magnetic recording media produced in the above examples and comparative examples, the crystal orientation (dispersion Δθ20 of the C axis of X-ray diffraction) of the Co-Cr perpendicularly magnetized film and the perpendicular magnetic properties [initial deposition measured in the direction perpendicular to the film surface] Coercive force of membrane (500 people) He
The coercive force (Hcl) of the perpendicularly magnetized film above and formed was investigated. The results are shown in Table 1.
第 1 表
第1表から明らかなごとく、本発明のCo−Cr垂直磁
化膜は、いずれも初期蒸着膜(500人)の保磁力が低
く、上層部において高保磁力を有し。Table 1 As is clear from Table 1, the Co--Cr perpendicularly magnetized films of the present invention all have a low coercive force in the initially deposited film (500 layers) and a high coercive force in the upper layer.
かつ結晶配向性が良好で、優れた垂直磁気特性を示して
いる。It also has good crystal orientation and exhibits excellent perpendicular magnetic properties.
以上詳細に説明したごとく、本発明のCo−Cr垂直磁
化膜の成膜初期における蒸着用蒸気流をイオン化するこ
とによって、Go−Cr膜の結晶配向性を著しく向上さ
せることができ、垂直磁気特性に優れた垂直磁化膜を有
する磁気記録媒体を得ることができる。As explained in detail above, by ionizing the deposition vapor flow at the initial stage of film formation of the Co-Cr perpendicularly magnetized film of the present invention, the crystal orientation of the Go-Cr film can be significantly improved, and the perpendicular magnetic properties A magnetic recording medium having a perpendicular magnetization film with excellent properties can be obtained.
第1図は本発明の実施例1において用いた真空蒸着装置
の構造を示す模式図、第2図は本発明の実施例2におい
て用いた真空蒸着装置の構造を示す模式図である。
l・・・基板 2・・・ヒータ3・・・蒸
発源 4・・・電子銃5・・・高周波コイル
6・・・マツチングボックス7・・・高周波電源
8・・・真空排気系9・・・供給ロール 1o・
・・回転ドラム11・・・巻取ロール 12.13・
・・蒸発源I4・・・イオン銃
代理人弁理士 中 村 純之助
第1図
?
5−唱凧奢雪栢
第2図
11−−ぷりRローもFIG. 1 is a schematic diagram showing the structure of a vacuum evaporation apparatus used in Example 1 of the present invention, and FIG. 2 is a schematic diagram showing the structure of a vacuum evaporation apparatus used in Example 2 of the present invention. l...Substrate 2...Heater 3...Evaporation source 4...Electron gun 5...High frequency coil
6...Matching box 7...High frequency power supply
8... Vacuum exhaust system 9... Supply roll 1o.
...Rotating drum 11... Winding roll 12.13.
...Evaporation source I4... Ion gun agent Junnosuke Nakamura Figure 1? 5-Shoukite Yukihoku 2nd figure 11--Puri R low too
Claims (1)
空蒸着法によりコバルトとクロムを主成分とする磁性層
を形成させて磁気記録媒体を製造する方法において、上
記磁性層の蒸着の初期に、コバルトとクロムを主成分と
する蒸着用蒸気流をイオン化して上記基板上に蒸着する
か、または上記蒸着用蒸気流に不活性ガスのイオンを照
射し、イオンを含む蒸着用蒸気流として上記基板上に蒸
着を行った後、上記蒸着用蒸気流のイオン化またはイオ
ン照射を停止して、引き続き蒸着を行いコバルトとクロ
ムを主成分とする垂直磁化膜を形成させることを特徴と
する磁気記録媒体の製造方法。 2、コバルトとクロムを主成分とする蒸着用蒸気流をイ
オン化する手段が、上記蒸気流中に設けられた高周波電
極によることを特徴とする特許請求の範囲第1項に記載
の磁気記録媒体の製造方法。 3、コバルトとクロムを主成分とする蒸着用蒸気流にイ
オンを照射する手段が、イオン銃によるアルゴンイオン
の照射であることを特徴とする特許請求の範囲第1項に
記載の磁気記録媒体の製造方法。[Claims] 1. A method for manufacturing a magnetic recording medium by forming a magnetic layer containing cobalt and chromium as main components on a non-magnetic substrate directly or through an underlayer by a vacuum evaporation method, comprising: At the beginning of the deposition of the magnetic layer, a vapor flow containing cobalt and chromium as main components is ionized and deposited on the substrate, or the vapor flow is irradiated with inert gas ions to generate ions. After performing vapor deposition on the substrate as a vapor flow containing vapor, stopping ionization or ion irradiation of the vapor flow and continuing vapor deposition to form a perpendicularly magnetized film containing cobalt and chromium as main components. A method of manufacturing a magnetic recording medium characterized by: 2. The magnetic recording medium according to claim 1, wherein the means for ionizing the vapor flow for vapor deposition containing cobalt and chromium as main components is a high-frequency electrode provided in the vapor flow. Production method. 3. The magnetic recording medium according to claim 1, wherein the means for irradiating the vapor flow for vapor deposition containing cobalt and chromium as main components is irradiation with argon ions using an ion gun. Production method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP25254187A JPH0196823A (en) | 1987-10-08 | 1987-10-08 | Production of magnetic recording medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP25254187A JPH0196823A (en) | 1987-10-08 | 1987-10-08 | Production of magnetic recording medium |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0196823A true JPH0196823A (en) | 1989-04-14 |
Family
ID=17238809
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP25254187A Pending JPH0196823A (en) | 1987-10-08 | 1987-10-08 | Production of magnetic recording medium |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0196823A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998015668A1 (en) * | 1996-10-07 | 1998-04-16 | Hitachi, Ltd. | Production method of laminate body, and the laminate body |
WO2003012160A1 (en) * | 2001-07-31 | 2003-02-13 | Asahi Optronics, Ltd. | High frequency ion plating vapor deposition system |
-
1987
- 1987-10-08 JP JP25254187A patent/JPH0196823A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998015668A1 (en) * | 1996-10-07 | 1998-04-16 | Hitachi, Ltd. | Production method of laminate body, and the laminate body |
WO2003012160A1 (en) * | 2001-07-31 | 2003-02-13 | Asahi Optronics, Ltd. | High frequency ion plating vapor deposition system |
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