JPH0556007B2 - - Google Patents
Info
- Publication number
- JPH0556007B2 JPH0556007B2 JP57225172A JP22517282A JPH0556007B2 JP H0556007 B2 JPH0556007 B2 JP H0556007B2 JP 57225172 A JP57225172 A JP 57225172A JP 22517282 A JP22517282 A JP 22517282A JP H0556007 B2 JPH0556007 B2 JP H0556007B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- atomic percent
- thin film
- alloy
- coated
- 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
- 239000010409 thin film Substances 0.000 claims description 36
- 229910052751 metal Inorganic materials 0.000 claims description 29
- 239000002184 metal Substances 0.000 claims description 29
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 28
- 239000010408 film Substances 0.000 claims description 19
- 229910052697 platinum Inorganic materials 0.000 claims description 14
- 230000001681 protective effect Effects 0.000 claims description 12
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 11
- 229910052735 hafnium Inorganic materials 0.000 claims description 11
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims description 11
- 229910052726 zirconium Inorganic materials 0.000 claims description 11
- 239000000758 substrate Substances 0.000 claims description 10
- 229910045601 alloy Inorganic materials 0.000 claims description 7
- 239000000956 alloy Substances 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 7
- 239000010941 cobalt Substances 0.000 claims description 7
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 7
- OFNHPGDEEMZPFG-UHFFFAOYSA-N phosphanylidynenickel Chemical group [P].[Ni] OFNHPGDEEMZPFG-UHFFFAOYSA-N 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- 229910001004 magnetic alloy Inorganic materials 0.000 claims description 4
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical group O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 3
- 229910000521 B alloy Inorganic materials 0.000 claims description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 2
- 229910001339 C alloy Inorganic materials 0.000 claims description 2
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- 229910052796 boron Inorganic materials 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims description 2
- 229910052741 iridium Inorganic materials 0.000 claims description 2
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 2
- 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 description 2
- 150000004767 nitrides Chemical class 0.000 claims description 2
- 229910052762 osmium Inorganic materials 0.000 claims description 2
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 claims description 2
- 229910052707 ruthenium Inorganic materials 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- 229910052715 tantalum Inorganic materials 0.000 claims description 2
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 2
- 239000010936 titanium Substances 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 2
- 229910052721 tungsten Inorganic materials 0.000 claims description 2
- 239000010937 tungsten Substances 0.000 claims description 2
- UCNNJGDEJXIUCC-UHFFFAOYSA-L hydroxy(oxo)iron;iron Chemical compound [Fe].O[Fe]=O.O[Fe]=O UCNNJGDEJXIUCC-UHFFFAOYSA-L 0.000 claims 1
- 230000004907 flux Effects 0.000 description 11
- 230000000052 comparative effect Effects 0.000 description 9
- 229910000531 Co alloy Inorganic materials 0.000 description 8
- 238000004544 sputter deposition Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- 238000005260 corrosion Methods 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 6
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 229910000838 Al alloy Inorganic materials 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 229910001096 P alloy Inorganic materials 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 229910044991 metal oxide Inorganic materials 0.000 description 3
- 150000004706 metal oxides Chemical class 0.000 description 3
- 238000007747 plating Methods 0.000 description 3
- 230000003746 surface roughness Effects 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 229910001566 austenite Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000007733 ion plating Methods 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 239000006249 magnetic particle Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- -1 or oxides Chemical class 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 229910017061 Fe Co Inorganic materials 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 238000007743 anodising Methods 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 125000006297 carbonyl amino group Chemical group [H]N([*:2])C([*:1])=O 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 125000000896 monocarboxylic acid group Chemical group 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 229930195734 saturated hydrocarbon Natural products 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 229930195735 unsaturated hydrocarbon Natural products 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/65—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition
- G11B5/656—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing Co
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/72—Protective coatings, e.g. anti-static or antifriction
- G11B5/727—Inorganic carbon protective coating, e.g. graphite, diamond like carbon or doped carbon
Description
本発明は磁気的記憶装置（磁気デイスク装置お
よび磁気ドラム装置等）に用いられる磁気記憶体
に関する。
現在実用化されている磁気記録体は不連続媒体
を有するものが主流である。この不連続媒体の磁
気記憶媒体は、γ−Fe2O3、CrO2・Fe、Fe−Co
等の磁性体粒子を有機樹脂からなる結合剤中に混
合分散して、基体上に塗布・乾燥・焼成して製造
するため、磁気記録媒体は磁性体粒子の大きさの
レベルで不連続である。
しかし、近年磁気記録媒体の高記録密度化の要
請により、連続薄膜媒体からなる保磁力の大きい
磁気記録媒体の研究開発が盛んに行なわれてい
る。この連続薄膜媒体は主にメツキ、真空蒸着、
スパツタ、イオンプレーテイング等の手法により
作られる金属薄膜からなるものと、真空蒸着、ス
パツタ、イオンプレーテイング等の手法により作
られるFe3O4又はγ−Fe2O3等の金属酸化物薄膜
からなるものが知られている。金属薄膜からなる
磁気記録媒体（以下金属薄膜体と称する）は高
温、高湿下の様な劣悪な雰囲気では腐食し易く、
十分耐食性のある金属薄膜媒体はまだ知られてい
ない。
本発明の目的は上述の現況に鑑み優れた磁気特
性を有しかつ耐食性がきわめて優れた金属薄膜媒
体を有する磁気記憶体を提供するものである。
すなわち本発明の磁気記憶体は鏡面研磨された
非磁性合金層又は非磁性金属酸化物層が被覆され
た基板上に１〜20原子パーセントのジルコニウム
及び20〜35原子パーセントの白金と残部がコバル
トからなる合金、又は、１〜20原子パーセントの
ハウニウムと20〜35原子パーセントの白金と残部
がコバルト合金からなるの金属薄膜媒体が被覆さ
れ、該媒体上に保護膜が被覆されて構成されてい
る。
次に図面を参照して本発明を詳細に説明する。
第１図は本発明の磁気記憶体の部分断面図であ
る。
第１図において磁気記憶体の基板１としてアル
ミ合金が軽くて加工性が良く安価なことから最も
良く用いられるが、場合によつてはチタン合金が
用いられることもある。基板表面は機械加工によ
り小さなうねり（円周方向で50μｍ以下、半径方
向で100μｍ以下）を有する面に仕上げられてい
る。
次にこの基板１の上に非磁性合金属２としてニ
ツケル−燐合金がめつきにより被覆され、この下
地体の表面は機械的研磨により最大表面粗さ
0.03μｍ以下に鏡面仕上げされる。次に上記下地
体の鏡面研磨面上にニツケル−燐合金がめつきさ
れ、その上に、金属薄膜媒体３として、ジルコニ
ウム又はハフニウム及び白金を含むコバルトから
なる金属薄膜体が高周波スパツタ法により被覆さ
れる。次に上記金属薄膜媒体３の上にSiO2に代
表される保護膜４が高周波スパツタ法により被覆
される。
金属薄膜媒体は抗磁力（Hc）500〜1200oe（ニ
ルステツド）、飽和磁束密度（Bs）12000G（ガウ
ス）以下角形比（Ｓ＝Br／Bs）0.7〜0.9、保磁力
角形比（S*）0.7〜0.9の範囲の磁気記録媒体とし
て優れたヒステリシス特性を示す。上記特性は金
属薄膜媒体中の白金およびジルコニウムまたはハ
フニムの量に大きく依存する。
第２図は残留磁束密度Br、抗磁力Hcおよび角
形比Ｓと保磁力角形S*の金属薄膜媒体中のジル
コニウムの原子パーセント濃度による変化を示し
た図であり、ジルコニウムが１〜20at％の範囲で
高記録密度可能な磁気記録媒体として使用できる
ことがわかる。
第３図は、Br、Hc、Ｓ、S*の金属薄膜媒体中
のハフニウムの原子パーセント濃度による変化を
示した図であり、ハフニウムが１〜20at％の範囲
で高記録密度可能な磁気記録媒体として使用でき
ることがわかる。
第４図は磁気記憶体を、25℃の水中に浸漬する
前の飽和磁束密度Boに対する25℃の水中に浸漬
した時の飽和磁束密度Bs（Bs／Bo）の時間変化
を示したものであり、値が1.0に近い程耐食性が
良い。
以上の様に白金を35原子パーセント以下及びジ
ルコニウムまたはハフニウムをそれぞれ20原子パ
ーセント以下、20原子パーセント以下含むコバル
ト合金からなる金属薄膜媒体３磁気記録媒体とし
て優れていることが分る。
金属薄膜媒体３の上に被覆される保護膜４は硬
質であることが望ましく、オスミウム、ルテニウ
ム、イリジウム、マンガン、タングステン等の金
属あるいはケイ素、チタン、タンタルまたはハフ
ニウムの酸化物、窒化物または炭化物あるいはホ
ウ素、炭素またはホウ素と炭素の合金あるいはポ
リ珪酸が望ましい。
これらの保護膜はスパツタにより形成できる。
ただしポリ珪酸は、テトラヒドロキシシランのイ
ソプロピルアルコールの溶液を塗布して300℃で
１時間焼成することにより形成する。
さらに保護膜４の上にＲ−Ｇ（ＲはＣ数10〜40
の飽和又は不飽和炭化水素又はふつ素化炭化水素
ＧはCOOH、OH、NH2、COOR′、Si（OR′）3、
CONH2までの官能基）からなる潤滑剤あるいは
フツ素化アルキルポリエーテル、ポリテトラフロ
ロエチレンテロマー等の潤滑剤を塗布することも
出来る。
また、非磁性合金層２として他に酸化アルミニ
ウムを用いることができる。
次にいくつかの例をあげて本発明を説明する。
実施例 １
基板１として施盤加工および熱矯正によつて十
分小さなうねり（円周方向で50μｍ以下および半
径方向で10μｍ以下）を有する面に仕上げられた
デイスク状アルミニウム合金盤上に非磁性合金層
２としてニツケル−燐合金を約50μｍの厚さにめ
つきし、このニツケル−燐めつき膜を最大表面粗
さ0.02μｍ、厚さ30μｍまで鏡面研磨仕上げした。
次にこのニツケル−燐めつき膜の上に金属薄膜
媒体３として高周波スパツタ法によりアルゴン圧
４×10-2torr、パワー密度15W／cm2にて膜厚500
Åのジルコニウムを５原子パーセント、白金を20
原子パーセント含むコバルト合金薄膜を被覆し
た。さらにこの金属薄膜媒体３の上にSiO2を200
Åの膜厚に高周波スパツタ法により被覆して磁気
デイスクを作つた。抗磁力Hc、残留磁束密度
Br、角形比Ｓ、保磁力角形比S*はそれぞれ
700oe、7200G、0.80、0.90であつた。
実施例 ２
実施例１と同様にして但し金属薄膜媒体３とし
てジルコニウムを10原子パーセントおよび白金を
20原子パーセント含むコバルト合金薄膜を膜厚
500Åで被覆して磁気デイスクを作つた。Hc、
Br、Ｓ、およびS*はそれぞれ500oe、6000G、
0.75、0.80であつた。
実施例 ３
実施例１と同様にして但し金属薄膜媒体３とし
てハフニウム５原子パーセント白金を20原子パー
セント含むコバルト合金薄膜を500Åで被覆して
磁気デイスクを作つた。Hc、Br、ＳおよびS*は
それぞれ800oe、6500G、0.80、0.90であつた。
実施例 ４
実施例１と同様に但し金属薄膜媒体３としてハ
フニウムを15原子パーセント、白金を20原子パー
セント含むコバルト合金薄膜を膜厚800Åにて被
覆して磁気デイスクを作つた。
Hc、Br、Ｓ、S*はそれぞれ600oe、4500G、
0.75、0.80であつた。
実施例 ５
実施例１と同様にして但しアルゴン圧４×
10-2torr、パワー密度1W／cm2にて磁気デイスク
を作つた。
Hc、Br、Ｓ、S*はそれぞれ1050oe、7000G、
0.80、0.80であつた。
実施例 ６
実施例３と同様にして但しアルゴン圧４×
10-2torr、パワー密度1W／cm2にて磁気デイスク
を作つた。
Hc、Br、Ｓ、S*はそれぞれ700oe、6500G、
0.80、0.80であつた。
実施例 ７
実施例１と同様にして但し非磁性合金層２とし
てアルミニウム合金からなる基板１の表面を陽極
酸化により非磁性金属酸化物層として酸化アルミ
ニウムを被覆しこの酸化アルミニウム最大表面粗
さ0.02μｍまで鏡面研磨仕上げして、磁気デイス
クを作つた。
実施例 ８
実施例１と同様にして但し保護膜４として次の
物質をそれぞれスパツタ法により800Åの厚さに
被覆してそれぞれ磁気デイスクを作つた。
The present invention relates to a magnetic storage body used in magnetic storage devices (magnetic disk devices, magnetic drum devices, etc.). Most of the magnetic recording media currently in practical use have discontinuous media. This discontinuous magnetic storage medium is made of γ-Fe 2 O 3 , CrO 2 ·Fe, Fe-Co
Magnetic recording media are manufactured by mixing and dispersing magnetic particles such as in a binder made of organic resin, coating it on a substrate, drying it, and baking it, so magnetic recording media are discontinuous at the level of the size of the magnetic particles. . However, in recent years, due to the demand for higher recording densities in magnetic recording media, research and development of magnetic recording media with high coercive force made of continuous thin film media has been actively conducted. This continuous thin film medium is mainly used for plating, vacuum deposition,
Thin films of metal made by methods such as sputtering and ion plating, and thin films of metal oxides such as Fe 3 O 4 or γ-Fe 2 O 3 made by methods such as vacuum evaporation, sputtering and ion plating. Something is known. Magnetic recording media made of thin metal films (hereinafter referred to as metal thin film bodies) are susceptible to corrosion in poor atmospheres such as high temperatures and high humidity.
Metal thin film media with sufficient corrosion resistance are not yet known. SUMMARY OF THE INVENTION In view of the above-mentioned current situation, an object of the present invention is to provide a magnetic memory having a metal thin film medium having excellent magnetic properties and extremely excellent corrosion resistance. That is, the magnetic memory of the present invention consists of 1 to 20 atomic percent zirconium, 20 to 35 atomic percent platinum, and the balance cobalt on a substrate coated with a mirror-polished nonmagnetic alloy layer or nonmagnetic metal oxide layer. The metal thin film medium is coated with an alloy of 1 to 20 atomic percent of haunium, 20 to 35 atomic percent of platinum, and the balance is cobalt, and a protective film is coated on the medium. Next, the present invention will be explained in detail with reference to the drawings. FIG. 1 is a partial cross-sectional view of the magnetic storage body of the present invention. In FIG. 1, aluminum alloy is most often used as the substrate 1 of the magnetic memory body because it is light, easy to work with, and inexpensive, but titanium alloy may be used in some cases. The surface of the substrate is finished by machining into a surface with small undulations (50 μm or less in the circumferential direction and 100 μm or less in the radial direction). Next, a nickel-phosphorus alloy as a non-magnetic alloy metal 2 is coated on this substrate 1 by plating, and the surface of this base body is mechanically polished to a maximum surface roughness.
Mirror finish to 0.03μm or less. Next, a nickel-phosphorus alloy is plated on the mirror-polished surface of the substrate, and a metal thin film medium 3 made of zirconium or cobalt containing hafnium and platinum is coated thereon by high-frequency sputtering. . Next, a protective film 4 typified by SiO 2 is coated on the metal thin film medium 3 by high frequency sputtering. The metal thin film media has a coercive force (Hc) of 500 to 1200 oe (Nirsted), a saturation magnetic flux density (Bs) of 12000 G (Gauss) or less, a squareness ratio (S = Br/Bs) of 0.7 to 0.9, and a coercive force squareness ratio (S * ) of 0.7 to 0.7. It exhibits excellent hysteresis characteristics as a magnetic recording medium in the range of 0.9. The above properties are highly dependent on the amount of platinum and zirconium or hafnim in the metal thin film medium. Figure 2 shows the changes in residual magnetic flux density Br, coercive force Hc, squareness ratio S, and coercive force squareness S * depending on the atomic percent concentration of zirconium in the metal thin film medium, where zirconium is in the range of 1 to 20 at%. It can be seen that it can be used as a magnetic recording medium capable of high recording density. Figure 3 shows changes in atomic percent concentration of hafnium in metal thin film media of Br, Hc, S, and S * , and is a magnetic recording medium capable of high recording density when hafnium is in the range of 1 to 20 at%. It can be seen that it can be used as Figure 4 shows the time change in the saturation magnetic flux density Bs (Bs/Bo) when the magnetic storage body is immersed in water at 25°C with respect to the saturation magnetic flux density Bo before it is immersed in water at 25°C. , the closer the value is to 1.0, the better the corrosion resistance. As described above, it can be seen that the metal thin film medium 3 made of a cobalt alloy containing platinum at 35 atomic percent or less and zirconium or hafnium at 20 atomic percent or less and 20 atomic percent or less, respectively, is excellent as a magnetic recording medium. The protective film 4 coated on the metal thin film medium 3 is preferably hard and is made of metals such as osmium, ruthenium, iridium, manganese, and tungsten, or oxides, nitrides, or carbides of silicon, titanium, tantalum, or hafnium. Boron, carbon, an alloy of boron and carbon, or polysilicic acid is preferable. These protective films can be formed by sputtering.
However, polysilicic acid is formed by applying a solution of tetrahydroxysilane in isopropyl alcohol and baking at 300° C. for 1 hour. Furthermore, on the protective film 4, R-G (R is C number 10 to 40)
The saturated or unsaturated hydrocarbons or fluorinated hydrocarbons G are COOH, OH, NH 2 , COOR′, Si(OR′) 3 ,
It is also possible to apply a lubricant consisting of CONH (functional groups up to 2 ) or a lubricant such as fluorinated alkyl polyether or polytetrafluoroethylene telomer. Furthermore, aluminum oxide can also be used as the nonmagnetic alloy layer 2. Next, the present invention will be explained by giving some examples. Example 1 A non-magnetic alloy layer 2 is formed on a disk-shaped aluminum alloy disk whose surface has sufficiently small waviness (50 μm or less in the circumferential direction and 10 μm or less in the radial direction) by lathe machining and thermal straightening as the substrate 1. A nickel-phosphorus alloy was plated to a thickness of approximately 50 μm, and the nickel-phosphorus plated film was mirror-polished to a maximum surface roughness of 0.02 μm and a thickness of 30 μm. Next, on this nickel-phosphorus plating film, a metal thin film medium 3 was formed using the high-frequency sputtering method to a film thickness of 500 at an argon pressure of 4×10 -2 torr and a power density of 15 W/cm 2 .
5 atomic percent of zirconium and 20 atomic percent of platinum
A thin film of cobalt alloy containing atomic percent was coated. Furthermore, 200% SiO 2 was added on top of this metal thin film medium 3.
A magnetic disk was fabricated by coating the film to a thickness of 1.5 Å using a high-frequency sputtering method. Coercive force Hc, residual magnetic flux density
Br, squareness ratio S, coercive force squareness ratio S * are respectively
They were 700oe, 7200G, 0.80, and 0.90. Example 2 Same as Example 1 except that 10 atomic percent of zirconium and 10 atomic percent of platinum were used as the metal thin film medium 3.
Cobalt alloy thin film containing 20 atomic percent
A magnetic disk was made by coating with 500 Å. Hc,
Br, S, and S * are respectively 500oe, 6000G,
It was 0.75 and 0.80. Example 3 A magnetic disk was fabricated in the same manner as in Example 1 except that the metal thin film medium 3 was coated with a cobalt alloy thin film containing 5 atomic percent of hafnium and 20 atomic percent of platinum to a thickness of 500 Å. Hc, Br, S and S * were 800oe, 6500G, 0.80 and 0.90, respectively. Example 4 A magnetic disk was fabricated in the same manner as in Example 1 except that the metal thin film medium 3 was coated with a cobalt alloy thin film containing 15 atomic percent hafnium and 20 atomic percent platinum to a thickness of 800 Å. Hc, Br, S, S * are 600oe, 4500G, respectively.
It was 0.75 and 0.80. Example 5 Same as Example 1 except that the argon pressure was 4×
A magnetic disk was made at 10 -2 torr and a power density of 1W/cm 2 . Hc, Br, S, S * are 1050oe, 7000G, respectively.
It was 0.80, 0.80. Example 6 Same as Example 3 except that the argon pressure was 4×
A magnetic disk was made at 10 -2 torr and a power density of 1W/cm 2 . Hc, Br, S, S * are 700oe, 6500G, respectively.
It was 0.80, 0.80. Example 7 In the same manner as in Example 1, except that the surface of the substrate 1 made of an aluminum alloy as the non-magnetic alloy layer 2 was coated with aluminum oxide as a non-magnetic metal oxide layer by anodizing, and the aluminum oxide had a maximum surface roughness of 0.02 μm. I polished it to a mirror finish and made a magnetic disk. Example 8 Magnetic disks were fabricated in the same manner as in Example 1, except that the protective film 4 was coated with the following materials to a thickness of 800 Å by sputtering.
【表】
実施例 ９
実施例１と同様に但し金属薄膜媒体３としてジ
ルコニウムを２原子パーセント、白金を20原子パ
ーセント含むコバルト合金薄膜を膜厚300Åにて
被覆して磁気デイスクを作つた。
Hc、Br、Ｓ、S*はそれぞれ900oe、9800G、
0.80、0.8であつた。
実施例 10
実施例１と同様に但し金属薄膜媒体３としてハ
フニウムを２原子パーセント、白金を20原子パー
セント含むコバルト合金薄膜を膜厚300Åにて被
覆して磁気デイスクを作つた。
Hc、Br、Ｓ、S*はそれぞれ980oe、9000G、
0.80、0.80であつた。
比較例 １
実施例１と同様にして但しニツケル−燐めつき
膜の上に膜厚1μｍのクロムを介して金属薄膜媒
体３としてコバルトを膜厚500Åで被覆して磁気
デイスクを作つた。抗磁力Hc、残留磁束密度
Br、角形比Ｓ、保磁力角形比S*はそれぞれ
600oe、13600G、0.8、0.8であつた。
比較例 ２
実施例１と同様にして白金を35at.％残りがコ
バルトからなるコバルト合金薄膜を膜厚500Åで
被覆して磁気デイスクを作つた。
抗磁力Hc、残留磁束密度Br、角形比Ｓ、保磁
力角形比S*はそれぞれ800oe、900G、0.85、0.85
であつた。
以上、実施例１〜10および比較例１，２で示し
た磁気デイスクを用いて電磁変換特性およびヘツ
ドとの摩耗試験および環境試験および水浸漬腐食
試験を行なつた結果、次の特性を得た。
電磁変換特性については実施例１〜10のデイス
クについて40000〜80000FRPIの記録密度が得ら
れたが、比較例１、２のデイスクでは
200000FRPIの記録密度しか得られなかつた。
ヘツドとの摩耗試験は２万回のコンタクトスタ
ートストツプテストを行なつたところデイスク表
面に傷は全く見られなかつた。又、温度80℃、相
対湿度90％で６ケ月放置する環境試験を行なつと
ところ実施例１〜10および比較例２についてはエ
ラーの増加数は全て０であつたが、比較例１のデ
イスクはエラーが100倍に増加した。
最後に実施例１〜10および比較例１、２のデイ
スクを切断して15mm×1.5mmの切片を作り、１ケ
月間25℃の水中に浸漬して飽和磁束密度Bsの変
化を調べたところ、第４図の様な結果が得られ
た。すなわち実施例１〜10は１ケ月の水中浸漬後
もBsの変化は全くなかつたが比較例１は50％、
比較例２は25％Bsが減少した。
以上の結果から本発明の磁気記憶体は優れた耐
食性（耐環境性）及び耐摩耗性及び高記録密度特
性を有していることが分つた。[Table] Example 9 A magnetic disk was fabricated in the same manner as in Example 1 except that the metal thin film medium 3 was coated with a cobalt alloy thin film containing 2 atomic percent of zirconium and 20 atomic percent of platinum to a thickness of 300 Å. Hc, Br, S, S * are 900oe, 9800G, respectively.
It was 0.80 and 0.8. Example 10 A magnetic disk was fabricated in the same manner as in Example 1, except that the metal thin film medium 3 was coated with a cobalt alloy thin film containing 2 atomic percent hafnium and 20 atomic percent platinum to a thickness of 300 Å. Hc, Br, S, S * are 980oe, 9000G, respectively.
It was 0.80, 0.80. Comparative Example 1 A magnetic disk was fabricated in the same manner as in Example 1, except that cobalt was coated as a metal thin film medium 3 with a thickness of 500 Å on a nickel-phosphorous film via a 1 μm thick chromium film. Coercive force Hc, residual magnetic flux density
Br, squareness ratio S, coercive force squareness ratio S * are respectively
It was 600oe, 13600G, 0.8, 0.8. Comparative Example 2 A magnetic disk was fabricated in the same manner as in Example 1 by coating a cobalt alloy thin film containing 35 at.% platinum and the remainder cobalt to a thickness of 500 Å. Coercive force Hc, residual magnetic flux density Br, squareness ratio S, and coercive force squareness ratio S * are 800oe, 900G, 0.85, and 0.85, respectively.
It was hot. As a result of conducting electromagnetic conversion characteristics, head wear tests, environmental tests, and water immersion corrosion tests using the magnetic disks shown in Examples 1 to 10 and Comparative Examples 1 and 2, the following characteristics were obtained. . Regarding electromagnetic conversion characteristics, recording densities of 40,000 to 80,000 FRPI were obtained for the disks of Examples 1 to 10, but the disks of Comparative Examples 1 and 2 did not.
A recording density of only 200,000 FRPI could be obtained. As for the wear test with the head, a contact start/stop test was performed 20,000 times and no scratches were found on the disk surface. In addition, when we conducted an environmental test in which the disk was left at a temperature of 80°C and a relative humidity of 90% for 6 months, the increase in the number of errors for Examples 1 to 10 and Comparative Example 2 was 0, but for the disk of Comparative Example 1. The error increased by a factor of 100. Finally, the disks of Examples 1 to 10 and Comparative Examples 1 and 2 were cut into 15 mm x 1.5 mm sections, and immersed in water at 25°C for one month to examine changes in saturation magnetic flux density Bs. The results shown in Figure 4 were obtained. That is, in Examples 1 to 10, there was no change in Bs at all after being immersed in water for one month, but in Comparative Example 1, it was 50%,
In Comparative Example 2, Bs decreased by 25%. From the above results, it was found that the magnetic memory of the present invention has excellent corrosion resistance (environmental resistance), wear resistance, and high recording density characteristics.
第１図は本発明の磁気記憶体の一実施例の部分
断面図である。
図中、１は基板、２は非磁性合金層、３は金属
薄膜媒体、４は保護膜である。第２図は本発明の
磁気記憶体に用いられる金属薄膜媒体における残
留磁束密度Br、抗磁力Hc、および角形比Ｓ、保
磁力角形比S*の金属薄膜媒体中のジルコニウム
の原子パーセント濃度による変化を示す図であ
り、第３図は同様にBr、Hc、Ｓ、S*の金属薄膜
媒体中のハフニウムの原子パーセント濃度による
変化を示す図である。第４図は本発明の磁気記憶
体を、25℃の水中に浸漬する前の飽和磁束密度
Boに対する25℃の水中に浸漬した時の飽和磁束
密度Bs（Bs／Bo）の時間変化を示す図である。
FIG. 1 is a partial cross-sectional view of one embodiment of the magnetic storage body of the present invention. In the figure, 1 is a substrate, 2 is a nonmagnetic alloy layer, 3 is a metal thin film medium, and 4 is a protective film. Figure 2 shows the changes in residual magnetic flux density Br, coercive force Hc, squareness ratio S, and coercive force squareness ratio S * of the metal thin film medium used in the magnetic storage body of the present invention depending on the atomic percent concentration of zirconium in the metal thin film medium. FIG. 3 is a diagram similarly showing changes in the atomic percent concentration of hafnium in metal thin film media of Br, Hc, S, and S * . Figure 4 shows the saturation magnetic flux density of the magnetic memory of the present invention before it is immersed in water at 25°C.
It is a figure showing the time change of saturation magnetic flux density Bs (Bs/Bo) when immersed in 25 degreeC water with respect to Bo.
Claims (1)
被覆され、前記非磁性金属又は前記非磁性酸化物
層上に１〜20原子パーセントのジルコニウムと20
〜35原子パーセントの白金と残部がコバルトから
なる合金、又は、１〜20原子パーセントのハフニ
ウムと20〜35原子パーセントの白金と残部がコバ
ルトからなる合金の金属薄膜媒体が被覆され、前
記金属薄膜媒体上に保護膜が被覆されていること
を特徴とする磁気記憶体。 ２ 非磁性合金層がニツケル−燐である特許請求
の範囲第１項記載の磁気記憶体。 ３ 非磁性酸化物層が酸化アルミニウムである特
許請求の範囲第１項記載の磁気記憶体。 ４ 保護膜がオスミウム、ルテニウム、イリジウ
ム、マンガン、又はタングステンである特許請求
の範囲第１項記載の磁気記憶体。 ５ 保護膜がケイ素、チタン、タンタル又はハフ
ニウムの酸化物、窒化物又は炭化物である特許請
求の範囲第１項記載の磁気記憶体。 ６ 保護膜がホウ素、炭素又はホウ素と炭素の合
金である特許請求の範囲第１項記載の磁気記憶
体。 ７ 保護膜がポリ珪酸である特許請求の範囲第１
項記載の磁気記憶体。[Scope of Claims] 1. A non-magnetic alloy layer or a non-magnetic oxide layer is coated on a substrate, and 1 to 20 atomic percent of zirconium and 20
coated with a metal thin film medium of an alloy consisting of ~35 atomic percent platinum and the balance cobalt, or an alloy consisting of 1 to 20 atomic percent hafnium, 20 to 35 atomic percent platinum, and the balance cobalt; A magnetic memory body characterized by having a protective film coated thereon. 2. The magnetic memory according to claim 1, wherein the nonmagnetic alloy layer is nickel-phosphorus. 3. The magnetic memory according to claim 1, wherein the nonmagnetic oxide layer is aluminum oxide. 4. The magnetic memory according to claim 1, wherein the protective film is made of osmium, ruthenium, iridium, manganese, or tungsten. 5. The magnetic memory according to claim 1, wherein the protective film is an oxide, nitride, or carbide of silicon, titanium, tantalum, or hafnium. 6. The magnetic memory according to claim 1, wherein the protective film is made of boron, carbon, or an alloy of boron and carbon. 7 Claim 1 in which the protective film is polysilicic acid
Magnetic storage medium described in Section 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57225172A JPS59116925A (en) | 1982-12-22 | 1982-12-22 | Magnetic storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57225172A JPS59116925A (en) | 1982-12-22 | 1982-12-22 | Magnetic storage medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59116925A JPS59116925A (en) | 1984-07-06 |
| JPH0556007B2 true JPH0556007B2 (en) | 1993-08-18 |
Family
ID=16825071
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57225172A Granted JPS59116925A (en) | 1982-12-22 | 1982-12-22 | Magnetic storage medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59116925A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4786553A (en) * | 1986-03-28 | 1988-11-22 | Hitachi, Ltd. | Magnetic recording medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50140899A (en) * | 1974-05-01 | 1975-11-12 | ||
| JPS57158036A (en) * | 1981-03-24 | 1982-09-29 | Nec Corp | Magnetic storage body |
| JPS57183004A (en) * | 1981-05-07 | 1982-11-11 | Fuji Photo Film Co Ltd | Magnetically recording medium |
-
1982
- 1982-12-22 JP JP57225172A patent/JPS59116925A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50140899A (en) * | 1974-05-01 | 1975-11-12 | ||
| JPS57158036A (en) * | 1981-03-24 | 1982-09-29 | Nec Corp | Magnetic storage body |
| JPS57183004A (en) * | 1981-05-07 | 1982-11-11 | Fuji Photo Film Co Ltd | Magnetically recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59116925A (en) | 1984-07-06 |
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