JPH06195694A - Magnetic recording medium and its production - Google Patents

Magnetic recording medium and its production

Info

Publication number
JPH06195694A
JPH06195694A JP34690192A JP34690192A JPH06195694A JP H06195694 A JPH06195694 A JP H06195694A JP 34690192 A JP34690192 A JP 34690192A JP 34690192 A JP34690192 A JP 34690192A JP H06195694 A JPH06195694 A JP H06195694A
Authority
JP
Japan
Prior art keywords
film
magnetic
protective film
hydrogen
substrate
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
Application number
JP34690192A
Other languages
Japanese (ja)
Inventor
Noriaki Yamagata
紀明 山形
Nobuyuki Yoshino
信行 吉野
Shuichi Hirai
修一 平井
Michihide Ozawa
道秀 小沢
Tetsushi Sudo
哲史 須藤
Masami Asanuma
正実 浅沼
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Denka Co Ltd
Original Assignee
Denki Kagaku Kogyo KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Denki Kagaku Kogyo KK filed Critical Denki Kagaku Kogyo KK
Priority to JP34690192A priority Critical patent/JPH06195694A/en
Publication of JPH06195694A publication Critical patent/JPH06195694A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To form a hydrocarbon film as a protective film having a low coefft. of friction, hardly causing sticking and excellent in CSS resistance and to obtain a magnetic recording medium having high reliability and a long service life. CONSTITUTION:An underlayer 3, a magnetic film 4 and a protective film 5 are formed on a nonmagnetic substrate 1. The protective film 5 is a hydrocarbon film having (60:40)-(90:10) atomic ratio of carbon: hydrogen and 80-95% of hydrogen-carbon bonds have sp<3> structure. The protective film 5 is formed by sputtering with a carbonaceous target while keeping the substrate 1 at 150-250 deg.C in an atmosphere of a gaseous mixture contg. gaseous hydrocarbon having <=50% concn. and gaseous hydrogen and/or inert gas.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、耐久性のすぐれた保護
膜を有する磁気記録媒体およびその製造方法に関するも
のである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium having a protective film with excellent durability and a method for manufacturing the same.

【0002】[0002]

【従来の技術】磁気記録再生装置では、その多くが起動
および停止時に記録再生ヘッドすなわち磁気ヘッドと磁
気ディスクとが接触する、コンタクト・スタート・スト
ップ(以下CSS と記す )方式を採用している。このため
磁気ディスクの磁気ヘッドとの接触による摩耗は避けら
れず、摩耗が進み損傷にいたれば信頼性に係わる重要な
問題となる。そこで磁性膜上に磁性膜の保護および磁気
ヘッドとの潤滑を目的として炭素質保護膜及び潤滑膜を
形成することが行われている。上記炭素質膜は例えば炭
素をターゲットとし、アルゴンに水素を含むガス雰囲気
下(米国特許第 5,045,165号)、炭化水素を含むガス雰
囲気下(特開昭60-155668)においてスパッタリングによ
り形成することができる。
2. Description of the Related Art Most of magnetic recording / reproducing apparatuses adopt a contact start / stop (hereinafter referred to as CSS) method in which a recording / reproducing head, that is, a magnetic head and a magnetic disk come into contact with each other at the time of starting and stopping. Therefore, wear due to contact of the magnetic disk with the magnetic head is unavoidable, and if the wear progresses and damage occurs, it becomes an important problem related to reliability. Therefore, a carbonaceous protective film and a lubricating film have been formed on the magnetic film for the purpose of protecting the magnetic film and lubricating the magnetic head. The carbonaceous film can be formed, for example, by sputtering in a gas atmosphere containing hydrogen in argon (US Pat. No. 5,045,165) and in a gas atmosphere containing hydrocarbon (JP-A-60-155668). .

【0003】[0003]

【発明が解決しようとする課題】近年、磁気ヘッドの低
浮上化および小径化が進み磁気ディスクの耐久性に対す
る要求は日に日に厳しくなってきている。前記製造法に
より形成される従来の炭素質膜は優れた耐摩耗性と潤滑
特性を兼ね備えた耐久性のある保護膜ではあるが、最近
のさらに厳しい耐久性に対する要求に対応することが困
難となってきている。本発明は、この様な要求に答える
べく保護膜の組成及び構造について検討し、潤滑性、耐
久性、特にCSS 特性を向上させた炭化水素質膜からなる
保護膜を有する磁気記録媒体を提供することを目的とし
ている。
In recent years, the flying height and the diameter of magnetic heads have been reduced, and the demand for durability of magnetic disks has become stricter day by day. The conventional carbonaceous film formed by the above-mentioned manufacturing method is a durable protective film having both excellent wear resistance and lubricating properties, but it is difficult to meet the recent demands for even more severe durability. Is coming. The present invention investigates the composition and structure of a protective film in order to meet such requirements, and provides a magnetic recording medium having a protective film made of a hydrocarbonaceous film with improved lubricity and durability, especially CSS characteristics. Is intended.

【0004】[0004]

【課題を解決するための手段】本発明の特徴は、非磁性
基板上に下地膜、磁性膜及び保護膜が形成された磁気記
録媒体において、前記保護膜は(炭素/水素)の原子比
が(60/40)以上(90/10)以下である炭化水素質膜か
らなり、かつ水素が結合している炭素の結合状態(sp2
構造+sp3 構造)のうち、sp3 構造の割合が80%以上95
%以下である磁気記録媒体である。
A feature of the present invention is that in a magnetic recording medium in which a base film, a magnetic film and a protective film are formed on a non-magnetic substrate, the protective film has a (carbon / hydrogen) atomic ratio. (60/40) or more and (90/10) or less of a hydrocarbonaceous film, and the bonding state of carbon to which hydrogen is bonded (sp 2
Structure + sp 3 structure), the ratio of sp 3 structure is 80% or more 95
% Magnetic recording medium.

【0005】その製造方法の特徴は濃度50%以下の炭化
水素ガス、並びに水素ガス及び/又は不活性ガスを含む
混合ガス雰囲気中で、非磁性基板上に形成された磁性膜
を有する基板の温度を 150℃以上 250℃以下に保持し
て、炭素質のターゲットを用いて、前記磁性膜上に前記
記載の保護膜を形成することにある。また、エチレンを
含む濃度50%以下の炭化水素ガス並びに、水素ガスまた
は不活性ガスのうちの一種以上のガスとの混合ガス雰囲
気中で、非磁性基板上に形成された磁性膜を有する基板
の温度を 150℃以上 250℃以下に保持するとともに、前
記基板に負のバイアス電圧を印加して、炭素質のターゲ
ットを用いて磁性膜上に前記記載の保護膜を形成するこ
とを特徴とするものである。
The characteristic of the manufacturing method is that the temperature of a substrate having a magnetic film formed on a non-magnetic substrate in a mixed gas atmosphere containing a hydrocarbon gas having a concentration of 50% or less and hydrogen gas and / or an inert gas. Is maintained at 150 ° C. or higher and 250 ° C. or lower, and the protective film described above is formed on the magnetic film by using a carbonaceous target. Further, in a mixed gas atmosphere of a hydrocarbon gas containing ethylene at a concentration of 50% or less and one or more gases of hydrogen gas or an inert gas, a substrate having a magnetic film formed on a non-magnetic substrate A temperature is maintained at 150 ° C or higher and 250 ° C or lower, and a negative bias voltage is applied to the substrate to form the protective film described above on the magnetic film using a carbonaceous target. Is.

【0006】以下本発明について詳細に説明する。なお
この磁気記録媒体の断面図を図1に示す。ニッケル−燐
めっき膜を被覆したアルミ合金基板の表面をポリッシン
グ処理し、さらにテクスチャー加工により微細な凹凸2
を形成した非磁性基板の上に下地膜3および磁性膜4を
設ける。前記非磁性基板はアルマイト、ガラス、カーボ
ン、セラミクス、チタン、シリコン等、特に材質は限定
されない。なおポリッシング処理、テクスチャー加工は
特に行わなくても良い。また、下地膜はクロム、モリブ
テン、チタンあるいはそれらの金属を含む合金であり、
その材質はとくに限定されない。磁性膜はコバルト−ニ
ッケル−クロム、コバルト−クロム−タンタル、コバル
ト−クロム−プラチナ等の合金であり、その材質は特に
限定されるものではない。
The present invention will be described in detail below. A sectional view of this magnetic recording medium is shown in FIG. The surface of an aluminum alloy substrate coated with a nickel-phosphorus plating film is subjected to polishing treatment and further textured to produce fine irregularities 2.
The base film 3 and the magnetic film 4 are provided on the non-magnetic substrate on which is formed. The non-magnetic substrate is not particularly limited in material such as alumite, glass, carbon, ceramics, titanium and silicon. The polishing process and the texture process may not be performed. The base film is chromium, molybdenum, titanium or an alloy containing these metals,
The material is not particularly limited. The magnetic film is an alloy such as cobalt-nickel-chromium, cobalt-chromium-tantalum, cobalt-chromium-platinum, and the material thereof is not particularly limited.

【0007】さらに磁性膜の上に炭化水素質膜を保護膜
としてスパッタリング法により設ける。スパッタリング
は、濃度50%以下の炭化水素ガス、並びに水素ガス及び
/又は不活性ガスを含む混合ガス雰囲気で行う。前記炭
化水素ガスはメタン、メチレン、エチレン、アセチレ
ン、プロピレン、プロパン、ベンゼン、スチレン等が使
用されるが炭化水素ガスであれば特に限定されるもので
はない。また、不活性ガスは、ヘリウム、ネオン、アル
ゴン、クリプトン、キセノン等が使用されるが、特に限
定されるものではない。スパッタガス圧は0.5mTorrから
15mTorr が適当である。炭化水素の濃度が50%より大き
いと、形成された保護膜の硬度が小さくなり好ましくな
い。
Further, a hydrocarbon film is provided as a protective film on the magnetic film by a sputtering method. Sputtering is performed in a mixed gas atmosphere containing a hydrocarbon gas having a concentration of 50% or less, and hydrogen gas and / or an inert gas. As the hydrocarbon gas, methane, methylene, ethylene, acetylene, propylene, propane, benzene, styrene and the like are used, but the hydrocarbon gas is not particularly limited as long as it is a hydrocarbon gas. As the inert gas, helium, neon, argon, krypton, xenon or the like is used, but the inert gas is not particularly limited. Sputtering gas pressure is from 0.5mTorr
15mTorr is suitable. If the concentration of hydrocarbons is more than 50%, the hardness of the formed protective film becomes small, which is not preferable.

【0008】前記雰囲気中で保護膜を形成するスパッタ
リングを行うにあたって、非磁性基板上に形成された磁
性膜を有する基板の温度を 150℃以上 250℃以下に保持
して、炭素質のターゲットを用いてスパッタリングする
ことが重要である。基板の温度が 150℃以下であると摩
擦係数が増加しやすく、又 250℃以上であると保護膜の
硬度が低くなり、目的とする良好な保護膜は得られな
い。ターゲットの材質は炭素に限定されるものではな
く、他の金属を含む炭素質のターゲットを用いてもよ
い。
When performing the sputtering for forming the protective film in the atmosphere, the temperature of the substrate having the magnetic film formed on the non-magnetic substrate is kept at 150 ° C. or higher and 250 ° C. or lower, and a carbonaceous target is used. Sputtering is important. If the temperature of the substrate is 150 ° C. or lower, the friction coefficient tends to increase, and if it is 250 ° C. or higher, the hardness of the protective film becomes low and the desired good protective film cannot be obtained. The material of the target is not limited to carbon, and a carbonaceous target containing another metal may be used.

【0009】また、前記保護膜を形成する際に、磁性膜
が形成された基板に負のバイアス電圧を印加してスパッ
タリングを行うことによって磁性層の上に形成する潤滑
剤とのぬれ性のバラツキの少い前記構造の安定した炭化
水素素質保護膜を形成することができる。バイアス電圧
は通常−30V〜−550 Vで行われるが特にこのましくは
−30V〜−300 Vがよい。
Further, when the protective film is formed, a negative bias voltage is applied to the substrate on which the magnetic film is formed to perform sputtering, and thus the wettability of the lubricant formed on the magnetic layer varies. It is possible to form a stable hydrocarbon-based protective film having the above-mentioned structure and having a small amount of the above. The bias voltage is usually -30V to -550V, but -30V to -300V is particularly preferable.

【0010】スパッタ電力密度は通常1W/cm2 から4W/
cm2 が適当である。さらに、通常は保護膜の上にフッ素
係潤滑剤を塗布して磁気記録媒体が作製される。なお下
地膜および磁性膜の両方、または磁性膜をスパッタリン
グ法により設ける場合には、保護膜形成前にヒーターを
設置し、下地膜から保護膜まで連続してスパッタリング
により膜形成することができる。
Sputter power density is typically 1 W / cm 2 to 4 W /
cm 2 is suitable. Further, usually, a fluorine-containing lubricant is applied on the protective film to produce a magnetic recording medium. When both the base film and the magnetic film, or the magnetic film is provided by the sputtering method, a heater may be installed before forming the protective film, and the base film and the protective film may be continuously formed by sputtering.

【0011】上記の方法によって作製された磁気記録媒
体の保護膜中の炭素/水素の原子比は ERD法(Elastic
Recoil Detection) で分析し、また炭素の結合状態はFT
-IRで分析し後述する測定法で測定し決められる。
The carbon / hydrogen atomic ratio in the protective film of the magnetic recording medium produced by the above method is determined by the ERD method (Elastic method).
Recoil Detection) and the carbon bond state is FT
-It is determined by IR analysis and the measurement method described below.

【0012】本発明の炭化水素質膜からなる保護膜中の
(炭素/水素)の原子比は、(60/40)以上(90/10)
以下であり、水素が結合している炭素の結合状態(sp2
構造+sp3 構造)のうち、sp3 構造の割合が80%以上95
%以下である。(炭素/水素)の原子比は、(60/40)
より小さいと硬度が低く、(90/10)より大きいと潤滑
性が低く好ましくない。sp3 構造の割合が80%より小さ
いと硬度が低く好ましくない。95%より大きいと摩擦係
数増加しやすくなって好ましくない。
The (carbon / hydrogen) atomic ratio in the protective film made of the hydrocarbonaceous film of the present invention is (60/40) or more (90/10).
And the bond state of carbon to which hydrogen is bonded (sp 2
Structure + sp 3 structure), the ratio of sp 3 structure is 80% or more 95
% Or less. The atomic ratio of (carbon / hydrogen) is (60/40)
If it is smaller, the hardness is low, and if it is larger than (90/10), the lubricity is low, which is not preferable. If the proportion of the sp 3 structure is less than 80%, the hardness is low, which is not preferable. If it exceeds 95%, the friction coefficient tends to increase, which is not preferable.

【0013】[0013]

【作用】本発明においては、磁気記録媒体の保護膜が炭
化水素質膜からなり、(炭素/水素)の原子比が(60/
40)以上(90/10)以下でかつ、sp3 構造の割合が80%
以上95%下に構成されていることによって、保護膜の硬
度を適正に、耐摩耗係数を小さく、かつ潤滑剤とのぬれ
性を安定に保つことができ、耐久性特にCSS 特性の良好
な保護膜を有する磁気記録媒体を得ることができる。ま
た、炭化水素質膜なる保護膜を形成する際に、基板に負
のバイアス電圧をかける場合は、イオン化された雰囲気
ガスが保護膜表面に衝突し、不安定な保護膜粒子をエッ
チングするため、安定な保護膜が形成され、水に対する
接触角のバラツキが小さくなり、安定した品質の保護膜
を有する磁気記録媒体を得ることができる。
In the present invention, the protective film of the magnetic recording medium is made of a hydrocarbonaceous film, and the atomic ratio of (carbon / hydrogen) is (60 /
40) or more (90/10) or less and the ratio of sp 3 structure is 80%
With the composition below 95%, the hardness of the protective film can be made appropriate, the wear resistance coefficient can be kept small, and the wettability with the lubricant can be kept stable. Durability, especially good protection of CSS characteristics A magnetic recording medium having a film can be obtained. Further, when a negative bias voltage is applied to the substrate when forming the protective film made of a hydrocarbonaceous film, the ionized atmospheric gas collides with the protective film surface and etches unstable protective film particles. A stable protective film is formed, variations in contact angle with water are reduced, and a magnetic recording medium having a stable quality protective film can be obtained.

【0014】[0014]

【実施例】以下、本発明の実施例について図を用いて具
体的に説明する。 実施例1 ニッケル−燐めっき膜を被覆したアルミ合金基板の表面
に微細な凹凸2を形成した非磁性基板1の上に下地膜3
としてクロムを 500Å、磁性膜4としてコバルト−クロ
ム−タンタルを 500Å、さらに保護膜5として水素と炭
素とを含む炭化水素質膜を 200Å順次スパッタリング法
により形成した。また前記保護膜の上にフッ素系潤滑膜
6を25Å形成し、磁気ディスクを作製した。保護膜を形
成する際、ターゲットは黒鉛を使用した。スパッタリン
グを行う雰囲気ガスとしてはアルゴンとエチレンとの混
合ガスを使用し、ガスの濃度、基板の温度、バイアス電
圧を表1に示すように設定した。またスパッタガス圧を
5mTorr 、スパッタ電力密度を4W/cm2 とした。
Embodiments of the present invention will be specifically described below with reference to the drawings. Example 1 A base film 3 was formed on a non-magnetic substrate 1 having fine irregularities 2 formed on the surface of an aluminum alloy substrate coated with a nickel-phosphorus plating film.
As the magnetic film 4, cobalt-chromium-tantalum is formed as 500Å, and as the protective film 5, a hydrocarbonaceous film containing hydrogen and carbon is formed as 200Å by a sequential sputtering method. Further, a fluorine-based lubrication film 6 was formed on the protective film in an amount of 25 liters to prepare a magnetic disk. When forming the protective film, graphite was used as the target. A mixed gas of argon and ethylene was used as an atmosphere gas for sputtering, and the gas concentration, substrate temperature, and bias voltage were set as shown in Table 1. The sputtering gas pressure was 5 mTorr and the sputtering power density was 4 W / cm 2 .

【0015】[0015]

【表1】 [Table 1]

【0016】〔水素と結合している炭素の結合状態の測
定法〕作製した炭化水素質膜の炭素の結合状態をFT-IR
(機種:PERKIN ELMER FT-IRSpectrometer 1760X)で分
析し、測定した各波形の2700cm-1〜3100cm-1付近を表2
に示すピーク位置でガウス分布で波形分離した。sp2
造の面積をピーク番号1と2の面積の和で求め、sp3
造の面積をピーク番号3から7までの面積の和で求め
た。それらの面積の総和の割合から水素の結合している
炭素の結合状態のsp3 構造とsp2 構造の割合を算出し
た。
[Measurement Method of Bonding State of Carbon Bound to Hydrogen] The bonded state of carbon of the produced hydrocarbonaceous film is measured by FT-IR.
(Model: PERKIN ELMER FT-IRSpectrometer 1760X) was analyzed in Table 2 near 2700cm -1 ~3100cm -1 of each was measured waveform
The waveform was separated with a Gaussian distribution at the peak position shown in. The area of the sp 2 structure was determined by the sum of the areas of peak numbers 1 and 2, and the area of the sp 3 structure was determined by the sum of the areas of peak numbers 3 to 7. The ratio of the sp 3 structure and the sp 2 structure of the bonded state of the hydrogen-bonded carbon was calculated from the ratio of the total of these areas.

【0017】[0017]

【表2】 [Table 2]

【0018】〔ERD 法による(炭素/水素)の原子比の
測定法〕形成した炭化水素質膜の炭素と水素の原子比に
ついては ERD法(Elastic Recoil Detection)で分析し
た。 ERD法は、ヘリウムイオンを試料の垂線から75度の
方向から試料に入射し、試料面から放出される水素原子
の量を検出する方法である。
[Method of measuring atomic ratio of (carbon / hydrogen) by ERD method] The atomic ratio of carbon and hydrogen in the formed hydrocarbonaceous film was analyzed by ERD method (Elastic Recoil Detection). The ERD method is a method in which helium ions are injected into the sample from a direction of 75 degrees from the vertical line of the sample and the amount of hydrogen atoms released from the sample surface is detected.

【0019】〔接触角の測定法〕また、作製した炭化水
素質膜からなる保護膜の水に対する接触角を接触角計
(協和界面科学株式会社製 型式S-150)で 100点測定
し、その平均と標準偏差を求め評価した。潤滑膜を形成
する前の保護膜でこれらの評価を行った。
[Method for Measuring Contact Angle] Further, the contact angle of water of the produced protective film made of a hydrocarbonaceous film was measured with a contact angle meter (Kyowa Interface Science Co., Ltd. model S-150) at 100 points, The average and standard deviation were calculated and evaluated. These evaluations were performed on the protective film before forming the lubricating film.

【0020】FT-IR で得られた結果およびその波形を波
形分離した結果を図2に示した。各ピークの面積、各構
造の総面積およびsp2 構造の総面積とsp3 構造の総面積
の割合を表3に示す。
The results obtained by FT-IR and the results of waveform separation of the waveforms are shown in FIG. Table 3 shows the area of each peak, the total area of each structure, and the ratio of the total area of the sp 2 structure to the total area of the sp 3 structure.

【0021】[0021]

【表3】 [Table 3]

【0022】次に、このようにして作製した潤滑膜を有
する磁気ディスクの耐久性試験を行った。耐久性試験
は、 CSS試験を開始する前の磁気ヘッドと磁気ディスク
との摩擦係数(以下摩擦係数と略す)とその摩擦係数が
1以上となる CSS回数(以下 CSS回数と略す)で評価し
た。これらの評価結果を表4に示す。
Next, a durability test of the magnetic disk having the lubricating film thus manufactured was conducted. The durability test was evaluated by the coefficient of friction between the magnetic head and the magnetic disk (hereinafter abbreviated as friction coefficient) before the CSS test was started and the number of CSS times when the coefficient of friction was 1 or more (hereinafter abbreviated as CSS frequency). The results of these evaluations are shown in Table 4.

【0023】[0023]

【表4】 [Table 4]

【0024】比較例1 ニッケル−燐めっき膜を被覆したアルミ合金基板を用い
て、実施例と同様の手順で形成された磁性膜上に、表5
に示す条件でスパッタリングして 200Åの厚さの炭化水
素質保護膜を形成した。また、実施例と同様前記保護膜
の上にフッ素系潤滑膜を25Å形成し、磁気ディスクを作
製した。これらの磁気ディスクについて実施例と同様の
方法で評価した結果を表6に示した。
Comparative Example 1 An aluminum alloy substrate coated with a nickel-phosphorus plating film was used to form a magnetic film on the magnetic film formed in the same procedure as in the example, as shown in Table 5.
A hydrocarbon protective film having a thickness of 200 Å was formed by sputtering under the conditions shown in. Further, a fluorine-based lubricating film was formed on the protective film in the same manner as in Example 25 to produce a magnetic disk. Table 6 shows the results of evaluating these magnetic disks by the same method as in the example.

【0025】[0025]

【表5】 [Table 5]

【0026】[0026]

【表6】 [Table 6]

【0027】比較例1から分かるように保護膜中に含ま
れる水素の濃度が少ないと保護膜の潤滑性がなくなり摩
擦係数が増加し CSS回数は減少する。また、保護膜中に
含まれる水素原子の割合が42以上{すなわち、この時の
(炭素/水素)の原子比は<(58/42)<(60/40 )で
ある。}と多くなると、摩擦係数は低いが保護膜の硬度
が低くくなり磁気ディスクにクラッシュが発生しやすく
なる。以上のことから、保護膜中に含まれる(炭素/水
素)の原子比を(60/40)以上(90/10)以下に設定す
ることにより摩擦係数の低い CSS特性の良好な磁気記録
媒体を得ることができる。
As can be seen from Comparative Example 1, when the concentration of hydrogen contained in the protective film is low, the lubricating property of the protective film is lost, the friction coefficient is increased, and the CSS number is decreased. Further, the ratio of hydrogen atoms contained in the protective film is 42 or more {that is, the atomic ratio of (carbon / hydrogen) at this time is <(58/42) <(60/40). }, The coefficient of friction is low, but the hardness of the protective film is low, and the magnetic disk is apt to crash. From the above, by setting the atomic ratio of (carbon / hydrogen) contained in the protective film to (60/40) or more and (90/10) or less, a magnetic recording medium with a low friction coefficient and good CSS characteristics can be obtained. Obtainable.

【0028】sp3 構造の割合については、比較例1に示
したようにsp3 構造の割合が大きくなると、摩擦係数が
極端に増加し、それに伴い摩擦係数が1以上になる CSS
回数が減少してしまう。そして、sp3 構造の割合が小さ
くなるにつれて摩擦係数は低くなり CSS回数も増加す
る。しかし、sp3 構造の割合をさらに小さくするとダイ
ヤモンド構造であるsp3 構造割合が減少し、保護膜の硬
度が小さくなるため、磁気ディスクにクラッシュが発生
した。これらのことは、sp3 構造が多くなるとダイヤモ
ンド構造が多くなるため、保護膜の硬度が増すが潤滑性
が劣ったためと考えられる。また逆に、sp3 構造が少な
くなると潤滑性の良いsp2 のグラファイト構造が多くな
るため、保護膜の潤滑性が増す変わりに硬度が減少した
と考えられる。
Regarding the proportion of sp 3 structure, as shown in Comparative Example 1, when the proportion of sp 3 structure becomes large, the coefficient of friction extremely increases, and accordingly, the coefficient of friction becomes 1 or more.
The number of times will decrease. Then, as the ratio of sp 3 structure decreases, the friction coefficient decreases and the number of CSS increases. However, if the ratio of the sp 3 structure is further reduced, the ratio of the sp 3 structure which is the diamond structure is decreased and the hardness of the protective film is decreased, so that the magnetic disk crashes. It is considered that these are because the diamond structure increases as the sp 3 structure increases, and thus the hardness of the protective film increases, but the lubricity deteriorates. On the other hand, when the sp 3 structure decreases, the graphite structure of sp 2 having good lubricity increases, so it is considered that the hardness decreases while the lubricity of the protective film increases.

【0029】実施例2 非磁性基板上に磁性膜が形成された基板にバイアス電圧
を印加し表7に示す条件で保護膜を形成した。その評価
結果を表8に示した。バイアス電圧を印加した磁気ディ
スクは印加しないものよりも水に対する接触角の標準偏
差が小さくなる。保護膜形成中にバイアス電圧を印加す
るとイオン化された不活性ガスが保護膜表面に衝突し不
安定な保護膜粒子をエッチングするため、安定な保護膜
が形成され水に対する接触角のばらつきが小さくなった
と考えられる。
Example 2 A bias film was applied to a substrate having a magnetic film formed on a non-magnetic substrate to form a protective film under the conditions shown in Table 7. The evaluation results are shown in Table 8. The magnetic disk to which the bias voltage is applied has a smaller standard deviation of the contact angle to water than the magnetic disk to which the bias voltage is not applied. When a bias voltage is applied during the formation of the protective film, the ionized inert gas collides with the surface of the protective film and etches unstable protective film particles, forming a stable protective film and reducing the variation of the contact angle with water. It is thought that

【0030】[0030]

【表7】 [Table 7]

【0031】[0031]

【表8】 [Table 8]

【0032】実施例3 表9に示す雰囲気ガス及び基板温度、バイアス電圧で保
護膜を形成した。その評価結果を表10に示した。メタ
ン、アセチレン、水素を含む混合ガス雰囲気中で形成し
た保護膜は、エチレンを含む混合ガス雰囲気中で形成し
た保護膜よりも、摩擦係数は若干高く、 CSS回数は若干
少ないが、(炭素/水素)の割合が(60/40)以上(90
/10)以下であり、かつ水素が結合している炭素の結合
状態のうち、sp3 構造の割合が80%以上95%以下である
炭化水素質膜が形成されおり、摩擦係数、 CSS回数の良
好な保護膜を形成することができる。
Example 3 A protective film was formed with the atmospheric gas, substrate temperature and bias voltage shown in Table 9. The evaluation results are shown in Table 10. The protective film formed in a mixed gas atmosphere containing methane, acetylene, and hydrogen has a slightly higher friction coefficient and a slightly lower CSS number than the protective film formed in a mixed gas atmosphere containing ethylene, but (carbon / hydrogen ) Ratio is (60/40) or more (90
/ 10) or less, and among the bonded states of hydrogen-bonded carbon, a hydrocarbon film with a sp 3 structure ratio of 80% or more and 95% or less is formed. A good protective film can be formed.

【0033】[0033]

【表9】 [Table 9]

【0034】[0034]

【表10】 [Table 10]

【0035】[0035]

【発明の効果】本発明によれば磁気記録媒体の保護膜と
して、(炭素/水素)の原子比が(60/40)以上(90/
10)以下であり、かつ水素が結合している炭素の結合状
態のうち、sp3 構造の割合が80%以上95%以下である炭
化水素質膜を形成することにより、従来の炭素膜と比較
して潤滑性、耐久性、特に CSS特性の良好な保護膜を形
成することができる。
According to the present invention, as a protective film of a magnetic recording medium, the atomic ratio of (carbon / hydrogen) is (60/40) or more (90/40).
10) or less, and among the bonding state of carbon hydrogen is bonded, by forming a hydrocarbon membrane fraction of sp 3 structure is 95% or more and 80% or less, compared with conventional carbon film Thus, it is possible to form a protective film having excellent lubricity and durability, especially CSS characteristics.

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

【図1】図1は本発明の一例を示す磁気記録媒体の断面
図である。
FIG. 1 is a cross-sectional view of a magnetic recording medium showing an example of the present invention.

【図2】図2はFT-IR 測定で得られた実測波形と分離波
形の例を示したものである。
FIG. 2 shows an example of a measured waveform and a separated waveform obtained by FT-IR measurement.

【符号の説明】[Explanation of symbols]

1:非磁性基板 2:微細な凹凸 3:下地膜 4:磁性膜 5:保護膜 6:潤滑膜 1: non-magnetic substrate 2: fine unevenness 3: base film 4: magnetic film 5: protective film 6: lubrication film

───────────────────────────────────────────────────── フロントページの続き (72)発明者 小沢 道秀 群馬県渋川市中村1135 電気化学工業株式 会社渋川工場内 (72)発明者 須藤 哲史 群馬県渋川市中村1135 電気化学工業株式 会社渋川工場内 (72)発明者 浅沼 正実 群馬県渋川市中村1135 電気化学工業株式 会社渋川工場内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Michihide Ozawa 1135 Nakamura, Shibukawa City, Gunma Prefecture, Shibukawa Plant Co., Ltd. (72) Inventor Masami Asanuma 1135 Nakamura, Shibukawa-shi, Gunma Electric Chemical Industry Co., Ltd.Shibukawa factory

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 非磁性基板上に下地膜、磁性膜及び保護
膜が形成された磁気記録媒体において、前記保護膜は
(炭素/水素)の原子比が(60/40)以上(90/10)以
下である炭化水素質膜からなり、かつ水素が結合してい
る炭素の結合状態(sp2 構造+sp3 構造)のうち、sp3
構造の割合が80%以上95%以下であることを特徴とする
磁気記録媒体。
1. A magnetic recording medium in which a base film, a magnetic film and a protective film are formed on a non-magnetic substrate, wherein the protective film has an atomic ratio of (carbon / hydrogen) of (60/40) or more (90/10). ) Of the following bonded states of carbon (hydrogen-bonded carbon (sp 2 structure + sp 3 structure), which consists of a hydrocarbonaceous film, sp 3
A magnetic recording medium having a structure ratio of 80% or more and 95% or less.
【請求項2】 濃度50%以下の炭化水素ガス、並びに水
素ガス及び/又は不活性ガスを含む混合ガス雰囲気中
で、非磁性基板上に形成された磁性膜を有する基板の温
度を 150℃以上 250℃以下に保持して、炭素質のターゲ
ットを用いて、前記磁性膜上に請求項1記載の保護膜を
形成することを特徴とする磁気記録媒体の製造方法。
2. The temperature of a substrate having a magnetic film formed on a non-magnetic substrate is 150 ° C. or higher in a mixed gas atmosphere containing a hydrocarbon gas having a concentration of 50% or less and hydrogen gas and / or an inert gas. A method for manufacturing a magnetic recording medium, which is characterized in that the protective film according to claim 1 is formed on the magnetic film by using a carbonaceous target while maintaining the temperature at 250 ° C. or lower.
【請求項3】 エチレンガスを含む濃度50モル%以下の
炭化水素ガス、並びに水素ガス及び/又は不活性ガスを
含む混合ガス雰囲気中で、非磁性基板上に形成された磁
性膜を有する基板の温度を 150℃以上 250℃以下に保持
するとともに、前記基板に負のバイアス電圧を印可し
て、炭素質のターゲットを用いて、前記磁性膜上に請求
項1記載の保護膜を形成することを特徴とする磁気記録
媒体の製造方法。
3. A substrate having a magnetic film formed on a non-magnetic substrate in a mixed gas atmosphere containing a hydrocarbon gas containing ethylene gas at a concentration of 50 mol% or less, and a hydrogen gas and / or an inert gas. The protective film according to claim 1 is formed on the magnetic film by using a carbonaceous target while maintaining the temperature at 150 ° C. or higher and 250 ° C. or lower and applying a negative bias voltage to the substrate. A method for manufacturing a characteristic magnetic recording medium.
JP34690192A 1992-12-25 1992-12-25 Magnetic recording medium and its production Pending JPH06195694A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP34690192A JPH06195694A (en) 1992-12-25 1992-12-25 Magnetic recording medium and its production

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP34690192A JPH06195694A (en) 1992-12-25 1992-12-25 Magnetic recording medium and its production

Publications (1)

Publication Number Publication Date
JPH06195694A true JPH06195694A (en) 1994-07-15

Family

ID=18386591

Family Applications (1)

Application Number Title Priority Date Filing Date
JP34690192A Pending JPH06195694A (en) 1992-12-25 1992-12-25 Magnetic recording medium and its production

Country Status (1)

Country Link
JP (1) JPH06195694A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6773784B2 (en) * 2002-04-08 2004-08-10 Hitachi, Ltd. Magnetic disk having ultrathin carbon protective film and magnetic disk apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6773784B2 (en) * 2002-04-08 2004-08-10 Hitachi, Ltd. Magnetic disk having ultrathin carbon protective film and magnetic disk apparatus

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