JPH0274013A - Magnetic thin film - Google Patents
Magnetic thin filmInfo
- Publication number
- JPH0274013A JPH0274013A JP63226265A JP22626588A JPH0274013A JP H0274013 A JPH0274013 A JP H0274013A JP 63226265 A JP63226265 A JP 63226265A JP 22626588 A JP22626588 A JP 22626588A JP H0274013 A JPH0274013 A JP H0274013A
- Authority
- JP
- Japan
- Prior art keywords
- film
- magnetic
- thin film
- magnetic thin
- composition
- 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.)
- Granted
Links
- 239000010409 thin film Substances 0.000 title claims abstract description 24
- 239000000203 mixture Substances 0.000 claims abstract description 13
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 3
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 3
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 3
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 3
- 229910052804 chromium Inorganic materials 0.000 claims abstract 2
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract 2
- 229910052758 niobium Inorganic materials 0.000 claims abstract 2
- 229910052721 tungsten Inorganic materials 0.000 claims description 2
- 239000010408 film Substances 0.000 abstract description 23
- 239000000758 substrate Substances 0.000 abstract description 16
- 239000000956 alloy Substances 0.000 abstract description 11
- 229910045601 alloy Inorganic materials 0.000 abstract description 11
- 230000004907 flux Effects 0.000 abstract description 8
- 238000000034 method Methods 0.000 abstract description 4
- 229920006395 saturated elastomer Polymers 0.000 abstract 2
- 230000005415 magnetization Effects 0.000 description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 238000005259 measurement Methods 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 229910000684 Cobalt-chrome Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000010952 cobalt-chrome Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000001004 secondary ion mass spectrometry Methods 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 240000000530 Alcea rosea Species 0.000 description 1
- 235000017334 Alcea rosea Nutrition 0.000 description 1
- 235000017303 Althaea rosea Nutrition 0.000 description 1
- 229910002441 CoNi Inorganic materials 0.000 description 1
- 229910018979 CoPt Inorganic materials 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004452 microanalysis Methods 0.000 description 1
- -1 polyethylene terephthalate Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Abstract
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、磁性薄膜例えば垂直磁気記録媒体に係わる。[Detailed description of the invention] [Industrial application field] The present invention relates to magnetic thin films, such as perpendicular magnetic recording media.
本発明による磁性薄膜は、組成式が
（Ｃｏａ Ｐｔｂ Ｍｃ） ＬＣＸ）−ＸＯＸ（但し、
ａ、ｂ、ｃ、ｘは原子％）
なる組成式で示され、その組成範囲が、ａ−１ｏｏ−ｂ
−Ｃ
Ｏ≦ｂ≦５０
０．１≦ｃ≦３０
０≦ｘ≦１５
であり、上記Ｍが、Ｔｉ、 Ｚｒ、 Ｖ ＋ Ｃｒ、
Ｎｂ、 Ｍａｔ ＴａｒＷのうちの１種以上である磁性
薄膜を構成することによって高い垂直保磁力Ｍｃ工ない
しは高飽和磁束密度を有し高い垂直異方性磁界を保持し
た垂直磁気記録媒体として好適な、磁性薄膜を得る。The magnetic thin film according to the present invention has a compositional formula of (Coa Ptb Mc) LCX)-XOX (however,
a, b, c, x are atomic %), and the composition range is a-1oo-b
-C O≦b≦50 0.1≦c≦30 0≦x≦15, and the above M is Ti, Zr, V + Cr,
Suitable as a perpendicular magnetic recording medium that has a high perpendicular coercive force Mc or high saturation magnetic flux density and maintains a high perpendicular anisotropic magnetic field by configuring a magnetic thin film of one or more of Nb, Mat TarW, Obtain a magnetic thin film.
従来の薄膜磁気記録媒体として用いられる磁性薄膜の、
等方性、すなわち面内磁化による磁性薄膜としては、Ｃ
ｏＮｉ、 ＣｏＰ、 ＣｏＰｔ等の合金磁性薄膜が知ら
れている。これらＣｏＮｉ及びＣｏＰによる各磁性薄膜
は、柱状構造を利用した硬磁気特性で、その飽和磁束密
度Ｂｓは約１０ｋＧ、保磁力Ｈｃは、約１（ｋＯｅ）な
いしはそれ以下である。また、ＣｏＰＬ磁性！繞につい
ては、例えば特開昭５８−２００５１３号公報にその開
示があるが、この場合、その膜厚が３００Å以下におい
ては１．５ （ｋＯｅ ）以上に及ぶ高い保磁力Ｈｃを
示すものの、その膜厚が犬となると、ＢＳは１０ｋＧ前
後で、Ｈｃは高々 ７００ Ｃ０ｅ）である。of magnetic thin films used as conventional thin film magnetic recording media.
As a magnetic thin film with isotropy, that is, in-plane magnetization, C
Alloy magnetic thin films such as oNi, CoP, and CoPt are known. Each of these magnetic thin films made of CoNi and CoP has hard magnetic properties utilizing a columnar structure, and has a saturation magnetic flux density Bs of about 10 kG and a coercive force Hc of about 1 (kOe) or less. Also, CoPL magnetic! For example, Japanese Patent Application Laid-Open No. 58-200513 discloses that the film exhibits a high coercive force Hc of 1.5 (kOe) or more when the film thickness is 300 Å or less. If the thickness is a dog, the BS is around 10 kG and the Hc is at most 700 C0e).
また、一方垂直磁化による磁性Ｉ膜としては、ＣｏＣｒ
＋ ＣｏＭｏ、 ＣｏＶ、 ＣｏＲｕ等の合金磁性ｓ繞
が知られている。この場合、これら合金のうち、液も磁
気特性の優れているＣｏＣｒ系についてその代表的な磁
気特性をみると、Ｂｓが４ （ｋＧ） 〜６ （ｋＧ）
であり、垂直保磁力Ｈｃ上は、この合金膜のスパッタリ
ング等の被着成膜時の基板温度が１５０℃加熱の場合は
、約１．５ （ｋＯｅ ）に及ぶ値を示すものの、その
成績時の基板温度が、室温程度である場合は、約３００
（Ｏｅ）である、そして、垂直方向の角型比（Ｍｒ／
７４５）上は約０．２．異方性磁界ＨＫは約４〜６（
ｋＯｅ）である、この場合、そのＢｓが比較的低いとい
う課題と共にそのＢｃ上は、成膜時の基板温度を高くし
ないと高い値を得ることができないことから、その基板
としては耐熱性の低い安価なポリエチレンテレフタレー
ト（ＰＩ！Ｔ）基板を用いることができないという課題
がある。On the other hand, as a magnetic I film with perpendicular magnetization, CoCr
+ Alloy magnetic layers such as CoMo, CoV, and CoRu are known. In this case, among these alloys, looking at the typical magnetic properties of the CoCr system, which has excellent liquid magnetic properties, Bs is 4 (kG) to 6 (kG).
The perpendicular coercive force Hc reaches a value of about 1.5 (kOe) when the substrate temperature is heated to 150°C during deposition of this alloy film by sputtering. When the substrate temperature is around room temperature, approximately 300
(Oe), and the vertical squareness ratio (Mr/
745) The upper value is about 0.2. The anisotropic magnetic field HK is approximately 4 to 6 (
In this case, the problem is that the Bs is relatively low, and a high value for the Bc cannot be obtained unless the substrate temperature is raised during film formation, so the substrate has low heat resistance. There is a problem that an inexpensive polyethylene terephthalate (PI!T) substrate cannot be used.
本発明は上述の課題を解決して成績時の基板温度を高め
ることなく、充分高い飽和磁束密度或いは（及び）Ａｉ
い保磁力を得ることができる磁性薄膜を提供する。The present invention solves the above-mentioned problems and achieves a sufficiently high saturation magnetic flux density or (and) Ai without increasing the substrate temperature during performance.
To provide a magnetic thin film that can obtain a high coercive force.
本発明は、ＣｏＰｔＢ系合金、ないしはＣｏＢ糸合金合
金るものであり、特に、
（Ｃｏａ Ｐｔｂ Ｂｃ） １ｏｏ−ｘＯｘ（但し、ａ
、ｂ、ｃ、ｘは原子％）
なる組成式で示され、その組成範囲が、ａ−１００−ｂ
−ｃ
Ｏ≦ｂ≦５０
０．１５ｃ≦３０
０≦ｘ≦１５
であって、上記Ｍが、Ｔｉ＋ Ｚｒ＋ Ｖ ＋ Ｃｒ、
Ｎｂ＋ Ｍｏ＋Ｔａ、 Ｗのうちの１種以上である磁
性薄膜を構成する。The present invention relates to a CoPtB alloy or a CoB thread alloy, and in particular, (Coa Ptb Bc) 1oo-xOx (however, a
, b, c, x are atomic %), and the composition range is a-100-b
−c O≦b≦50 0.15c≦30 0≦x≦15, and the above M is Ti+Zr+V+Cr,
The magnetic thin film is composed of one or more of Nb+Mo+Ta and W.
本発明による磁性ｗｌ膜は、成績時の基板温度を高める
ことなくまた比較的厚いｆｉｌ厚でも高い保磁力Ｈｃ、
ないしは高い飽和磁束密度−、ｉｂい異方性磁界を得る
ことができ、垂直磁化膜として用いて好適な特性を呈す
る。The magnetic wl film according to the present invention has a high coercive force Hc, even with a relatively thick film thickness, without increasing the substrate temperature during performance.
It is possible to obtain a high saturation magnetic flux density and a high anisotropic magnetic field, and exhibits suitable characteristics when used as a perpendicularly magnetized film.
スライドガラス基板上に、マグネトロン型スバンタ装置
によって磁性薄膜を作製する。そのスバフタ条件は、例
えば
磁性Ｗ映の膜厚： ５ｏｏｏ人
とした、この場合のターゲットは、凶、径４インチ。A magnetic thin film is produced on a slide glass substrate using a magnetron-type Svanta apparatus. For example, the vacuum condition is that the film thickness of the magnetic W film is 500 mm, and the target in this case is 4 inches in diameter.
厚さ３１１１１の０１Ｍ系の合金ターゲット上にその中
心から、所要の広がり角を有する、厚さ１ＩＩＩ！のｐ
ｔの扇形チップを３枚から６枚置いた複合ターゲットを
用いる。或いは例えば直径４インチ、厚さ３■のＣｏＭ
Ｐ を系合金ターゲットを用いる。A thickness of 1III with the required spread angle from the center on the 01M series alloy target of thickness 31111! p of
A composite target with 3 to 6 t sector chips is used. Or, for example, CoM with a diameter of 4 inches and a thickness of 3 cm.
A P-based alloy target is used.
実施例！
複合ターゲットを用い前記スバンタ方法及び条件でＣｏ
ｏ Ｐｔｚ２Ｔｉ２の磁性薄膜を作製した。しかしなが
ら、この場合、スバ７夕の開始に先立って行われるスパ
ッタ室内の排気によって得るバックグラウンド真空度Ｐ
ＢＧを変えた。そして各バックグラウンド真空度Ｐｓｃ
でのそれぞれ得られた磁性薄膜Ｃｏｖｃ Ｐ ｔ２２Ｔ
ｉ２中の酸素濃度を測定した。また、この各ＰＢＧに
等価な＠素分圧を、磁性ｉ膜中の酸素濃度との対応によ
って求めた。これらを、表１表 １
この実施例においては、Ｃｏフｓ Ｐｈ２Ｔｉ２膜につ
いての１葵中のｔｉＩ素濃度と、ＰＢＧ及びＰＯ２との
関係をみたものであるが、他の組成のＣｏＰ ＬＭ糸の
磁性薄膜についても、これの酸素濃度と、ＰＢＧ及びＰ
Ｏ２との関係は殆んど同等の関係となった。Example! Co using the above Svanta method and conditions using a composite target.
o A magnetic thin film of Ptz2Ti2 was produced. However, in this case, the background vacuum level P obtained by evacuation of the sputtering chamber prior to the start of the
I changed the BG. And each background vacuum degree Psc
The magnetic thin films Covc P t22T obtained at
The oxygen concentration in i2 was measured. In addition, the @element partial pressure equivalent to each PBG was determined based on the correspondence with the oxygen concentration in the magnetic i film. These are shown in Table 1. In this example, we looked at the relationship between the tiI element concentration in one hollyhock and PBG and PO2 for the CoP LM yarn of other compositions. Regarding the magnetic thin film, its oxygen concentration, PBG and P
The relationship with O2 was almost the same.
実施例２
前記スパンタ方法及び条件でＰｅＧ−４μｍ’ ｏ ｒ
ｒとして、各種合金ターゲット上にｐｔチップを載せ
た複合ターゲットを用いて各種組成の磁性薄膜を作製し
た。第１図Ａ−Ｆにこれら各磁性薄膜についての使用し
たターゲット、つまり、使用した合金ターゲットの組成
（原子％）と、これの上に配置したｐｉ扇形チップのタ
ーゲット全体の表面積に対して占める割合（％）と、得
られた薄膜の組成と、膜厚と、各磁気特性Ｈｃ↓Ｉ Ｈ
Ｃ” ＋ ＨＫ上、Ｈに、４πＭｓｔ Ｍｒ” ／ Ｍ
ｒ”の測定結果を示す、面、これら各磁気特性は、第２
図にその面内磁化曲線と垂直磁化曲線のモデル図上で示
した各値、つまり、垂直保磁力Ｈｃ” ＋面内保磁力Ｈ
ｃ“、異方性磁界Ｈに上。Example 2 PeG-4 μm' or
As r, magnetic thin films of various compositions were produced using a composite target in which a PT chip was mounted on various alloy targets. Figures 1A to 1F show the composition (atomic %) of the target used for each of these magnetic thin films, that is, the alloy target used, and the proportion of the surface area of the pi sector-shaped tip placed on top of the target to the total surface area of the target. (%), the composition of the obtained thin film, the film thickness, and each magnetic property Hc↓I H
C" + HK above, H, 4πMst Mr" / M
The surface showing the measurement result of r'', each of these magnetic properties is the second
Each value shown on the model diagram of the in-plane magnetization curve and perpendicular magnetization curve in the figure, that is, perpendicular coercive force Hc'' + in-plane coercive force H
c”, above the anisotropic magnetic field H.
ＨＫ／／、飽和磁束密度４πＭｓ、残留磁化比Ｍｒ↓／
Ｍｒ”の測定結果である。尚、このようにして得た磁性
Ｗｉ模膜中は、実施例１による表１から明らかなように
、ｍ素が４．２〜１０．７原子％含まれる。HK//, saturation magnetic flux density 4πMs, residual magnetization ratio Mr↓/
These are the measurement results for Mr''. As is clear from Table 1 according to Example 1, the magnetic Wi model film thus obtained contains 4.2 to 10.7 atomic % of m elements.
実ｈｆ１例３
厚さ５０００人の（ＣＯ？Ｇ Ｐｈｚ Ｔｉ２） ９６
０ ｓの組成による磁性薄膜を作製した。この場合の磁
化Ｍ−磁磁界８線線！＠３図に示す、同図中実線曲線は
垂直方向のＭ−８曲線、破線曲線は面内方向のＭ−８曲
線を示す。Actual hf1 example 3 thickness 5000 people (CO?G Phz Ti2) 96
A magnetic thin film with a composition of 0 s was produced. Magnetization M in this case - magnetic field 8 lines! In Figure @3, the solid line curve in the figure is the M-8 curve in the vertical direction, and the broken line curve is the M-8 curve in the in-plane direction.
尚、上述したところにおいて磁気特性は、試料振動型磁
力針によって測定されたものであり、膜組成は電子線プ
ローブマイクロアナリシス（εＰ？ｌＡ）と、 Ｉ
Ｐ Ｃ（Ｉｎｄｕｃｔｉｖｅｌｙ ＣｏｕｐＪｅｄ Ｐ
ｌａｓｍａ Ａｎａｌｙｓｆｆｉｓ ）発光分析の併用
により測定し、表１の膜中の酸素濃度は、酸素ドース量
の明確な標準試料との比較で２次イオン質量分析ＳＩＭ
Ｓ （Ｓｅｃｏｎｄａｒｙ Ｊｏｎ Ｍａｓ３Ｓｐｅｃ
ｔｒｏｓ＋ｅＬｅｒ）法とＥＰＭ八法へを併用して測定
した。In the above, the magnetic properties were measured using a sample vibrating magnetic needle, and the film composition was determined using electron beam probe microanalysis (εP?lA) and I
P C (Inductively CoupJed P
The oxygen concentration in the film shown in Table 1 is measured using secondary ion mass spectrometry (SIM) in comparison with a standard sample with a clear oxygen dose.
S (Secondary Jon Mas3Spec
The measurement was performed using a combination of the tros+eLer) method and the EPM eight method.
向、上述の各実施例においては、基板としてスライドガ
ラス坂を用いた場合であるが、そのほかポリイミド樹脂
基板、結晶化ガラス基板を始めとして、ＰＨＴ基板等各
種基板を用いることもできる。In each of the above embodiments, a slide glass slope is used as the substrate, but various other substrates such as a polyimide resin substrate, a crystallized glass substrate, a PHT substrate, etc. can also be used.
の各組成に対する磁気特性の測定結果を示す表図、第２
図はその説明に供するＭ−Ｈモデル図、第３図は本発明
による磁性Ｍ膜の一例のＭ−Ｈ曲線図である。A table showing the measurement results of magnetic properties for each composition of
The figure is an MH model diagram for explaining the same, and FIG. 3 is an MH curve diagram of an example of the magnetic M film according to the present invention.
〔発明の効果〕
上述の本発明による磁性薄膜は、成膜時の基板温度を高
めることなく、また、第１図でわかるよウニ例えば５０
００人に近い或いはこれ以上の膜厚においても、高いＨ
ｃ上ないしは飽和磁束密度と高い垂直異方性磁界ｌＫ／
／、つまり垂直磁気記録媒体としてすぐれた磁性薄膜を
得ることができる。[Effects of the Invention] The magnetic thin film according to the present invention described above does not increase the substrate temperature during film formation, and as can be seen in FIG.
High H even at film thickness close to or greater than 0.0
c or saturation magnetic flux density and high perpendicular anisotropy magnetic field lK/
/, that is, a magnetic thin film excellent as a perpendicular magnetic recording medium can be obtained.
更にまた、室温程度での成膜が可能であることから、Ｐ
ｔ１Ｔ等の低源な基板を用いることができるなど、実用
上大きな利益を有する。Furthermore, since it is possible to form a film at around room temperature, P
This has great practical advantages, such as being able to use a low-power substrate such as t1T.
Claims (1)
＿ｘ（但し、ａ，ｂ，ｃ，ｘは原子％） なる組成式で示され、その組成範囲が、 ａ＝１００−ｂ−ｃ ０≦ｂ≦５０ ０．１≦ｃ≦３０ ０≦ｘ≦１５ であり、 上記ＭはＴｉ，Ｚｒ，Ｖ，Ｃｒ，Ｎｂ，Ｍｏ，Ｔａ，Ｗ
のうちの１種以上である ことを特徴とする磁性薄膜。[Claims] (Co_aPt_bM_c)_1_0_0_-_xO
_x (where a, b, c, x are atomic %) The composition range is a=100-b-c 0≦b≦50 0.1≦c≦30 0≦x≦ 15, and the above M is Ti, Zr, V, Cr, Nb, Mo, Ta, W
A magnetic thin film characterized by being one or more of the following.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22626588A JP2625960B2 (en) | 1988-09-09 | 1988-09-09 | Magnetic thin film |
| EP89102895A EP0330116B1 (en) | 1988-02-22 | 1989-02-20 | Magnetic recording medium |
| KR1019890001965A KR970007795B1 (en) | 1988-02-22 | 1989-02-20 | Magnetio recording medium |
| DE68925045T DE68925045T2 (en) | 1988-02-22 | 1989-02-20 | Magnetic record carrier |
| HK98106793A HK1007625A1 (en) | 1988-02-22 | 1998-06-25 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22626588A JP2625960B2 (en) | 1988-09-09 | 1988-09-09 | Magnetic thin film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0274013A true JPH0274013A (en) | 1990-03-14 |
| JP2625960B2 JP2625960B2 (en) | 1997-07-02 |
Family
ID=16842496
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22626588A Expired - Fee Related JP2625960B2 (en) | 1988-02-22 | 1988-09-09 | Magnetic thin film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2625960B2 (en) |
-
1988
- 1988-09-09 JP JP22626588A patent/JP2625960B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2625960B2 (en) | 1997-07-02 |
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