JP4771222B2 - 垂直磁気記録媒体 - Google Patents
垂直磁気記録媒体 Download PDFInfo
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- JP4771222B2 JP4771222B2 JP2006248628A JP2006248628A JP4771222B2 JP 4771222 B2 JP4771222 B2 JP 4771222B2 JP 2006248628 A JP2006248628 A JP 2006248628A JP 2006248628 A JP2006248628 A JP 2006248628A JP 4771222 B2 JP4771222 B2 JP 4771222B2
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- 239000011159 matrix material Substances 0.000 claims description 6
- 150000004767 nitrides Chemical class 0.000 claims description 6
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Images
Classifications
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- 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
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/1278—Structure or manufacture of heads, e.g. inductive specially adapted for magnetisations perpendicular to the surface of the record carrier
-
- 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
- G11B5/657—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing inorganic, non-oxide compound of Si, N, P, B, H or C, e.g. in metal alloy or compound
-
- 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
- G11B5/658—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing oxygen, e.g. molecular oxygen or magnetic oxide
-
- 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
- G11B5/66—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers
- G11B5/676—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers having magnetic layers separated by a nonmagnetic layer, e.g. antiferromagnetic layer, Cu layer or coupling layer
-
- 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
- G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
- G11B5/7368—Non-polymeric layer under the lowermost magnetic recording layer
-
- 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
- G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
- G11B5/7368—Non-polymeric layer under the lowermost magnetic recording layer
- G11B5/7373—Non-magnetic single underlayer comprising chromium
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Metallurgy (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Description
非磁性基体1として表面が平滑な化学強化ガラス基板(HOYA社製N−5ガラス基板)を用い、これを洗浄後DCマグネトロンスパッタ装置内に導入し、Co5Zr8Nb(全原子を基準として5at%のZr、8at%のNb、および残余のCoで構成される。以下同様)ターゲットを用いて、膜厚60nmのCoZrNb非晶質軟磁性裏打ち層2を成膜した。次にRuターゲットを用いて、膜厚0.7nmのRu非磁性結合層3を成膜した。次に、Co20Cr10Pt4Bターゲットを用いて、膜厚6nmのCoCrPtB硬磁性ピニング層4を成膜した。軟磁性裏打ち層2、非磁性結合層3および硬磁性ピニング層4の製膜は、圧力0.67PaのArガス中で実施した。引き続いて、Ruターゲットを用いて、圧力4.0PaのArガス中で膜厚10nmのRu非磁性中間層5を成膜した。引き続いて、2層構成のグラニュラー構造を有する磁気記録層6を形成した。最初に、90(Co12Cr16Pt)−10SiO2ターゲットを用いて、ガス圧5.3Pa下で膜厚8nmのCoCrPt−SiO2第一磁気記録層を製膜し、引き続いて96(Co20Cr12Pt)−4SiO2ターゲットを用いて、ガス圧1.2Pa下で膜厚8nmのCoCrPt−SiO2第二磁気記録層を成膜した。最後に、材料ガスとしてエチレンを用い、ガス圧約0.13Pa下でのプラズマCVD法によって、膜厚4nmのC保護膜7を成膜し、得られた積層体を真空装置から取り出した。また、磁気記録層6以下の全ての層はDCマグネトロンスパッタリング法により製膜した。その後、ディップ法を用いて、膜厚2nmのパーフルオロポリエーテルからなる液体潤滑材層8を形成し、垂直磁気記録媒体とした。
CoZrNb軟磁性裏打ち層2成膜後に、Ni12Fe4Siターゲットを用いたDCマグネトロンスパッタ法によって膜厚6nmのNiFeSi軟磁性シード層を成膜したことを除いて、実施例1と全く同様にして垂直磁気記録媒体を作製した。
非磁性結合層3の形成において、Ruターゲットに代えてCuターゲットを用い、膜厚0.6nmのCu非磁性結合層3を成膜したことを除いて、実施例1の手順を繰り返して、垂直磁気記録媒体を作製した。また、実施例1と同様に、軟磁性裏打ち層2の特性を評価するためのサンプルを作製した。
硬磁性ピニング層4の形成において、Co20Cr10Pt4Bターゲットに代えて90(Co14Cr16Pt)−10SiO2ターゲットを用い、膜厚5nmのグラニュラー構造を有するCoCrPt−SiO2硬磁性ピニング層4を成膜したことを除いて、実施例1の手順を繰り返して、垂直磁気記録媒体を作製した。また、実施例1と同様に、軟磁性裏打ち層2の特性を評価するためのサンプルを作製した。
硬磁性ピニング層4の形成において、Co20Cr10Pt4Bターゲットに代えてCo20Crターゲットを用い、膜厚8nmのCoCr硬磁性ピニング層4を成膜したことを除いて、実施例1の手順を繰り返して、垂直磁気記録媒体を作製した。また、実施例1と同様に、軟磁性裏打ち層2の特性を評価するためのサンプルを作製した。
非磁性結合層3および硬磁性ピニング層4を形成しなかったことを除いて、実施例2の手順を繰り返して、垂直磁気記録媒体を作製した。また、実施例2と同様に、軟磁性裏打ち層2の特性を評価するためのサンプルを作製した。
非磁性基体として表面が平滑な化学強化ガラス基板(HOYA社製N−5ガラス基板)を用い、これを洗浄後DCマグネトロンスパッタ装置内に導入し、Co5Zr8Nbターゲットを用いて、膜厚30nmの第1のCoZrNbの非晶質軟磁性裏打ち層を成膜した。次に、Ruターゲットを用いて、膜厚0.7nmのRu層を成膜した。次いで、再度Co5Zr8Nbターゲットを用いて、膜厚30nmの第2のCoZrNbの非晶質軟磁性裏打ち層を成膜した。次に、Ni12Fe4Siターゲットを用いて膜厚6nmのNiFeSi軟磁性シード層を成膜した。引き続いて、Ruターゲットを用いて、圧力4.0PaのArガス中で膜厚10nmのRu非磁性結合層を成膜した。以下、実施例1と同様にして磁気記録層、保護膜および液体潤滑材層を形成し、垂直磁気記録媒体を作製した。
なお、実施例1、3、4および5の垂直磁気記録媒体では非磁性結合層3と硬磁性ピニング層4がシード層と同様の役割をするため、非磁性中間層5および磁気記録層6が適切に垂直配向(非磁性基体1表面に対して垂直方向にhcp構造の結晶のc軸が配向)した。一方、比較例1および2の層構成ではシード層を用いないと非磁性中間層および磁気記録層の垂直配向が得られないため、NiFeSiシード層を用いて実施例2と類似の構造とした。
2、102 軟磁性裏打ち層
3 非磁性結合層
4 硬磁性ピニング層
5 非磁性中間層
6、106 磁気記録層
7 保護膜
8 液体潤滑剤層
20 ヘッド磁場
Claims (9)
- 非磁性基体と、軟磁性裏打ち層と、非磁性結合層と、硬磁性ピニング層と、非磁性中間層と、磁気記録層とをこの順に有し、軟磁性裏打ち層の上層部と硬磁性ピニング層が非磁性結合層を介して常温で垂直方向に反強磁性結合しており、硬磁性ピニング層の磁化容易軸が非磁性基体表面に対して垂直方向であり、前記軟磁性裏打ち層が非磁性基体表面に対して平行かつ半径方向に一軸磁気異方性を有することを特徴とする垂直磁気記録媒体。
- 前記軟磁性裏打ち層が、非晶質であることを特徴とする請求項1に記載の垂直磁気記録媒体。
- 非磁性結合層が、V、Cr、Cu、Nb、Mo、Ru、Rh、Ta、W、ReおよびIrからなる群から選択される金属またはこれらを主成分とする合金からなることを特徴とする請求項1または2に記載の垂直磁気記録媒体。
- 非磁性結合層が2nm以下の膜厚を有することを特徴とする請求項1から3のいずれかに記載の垂直磁気記録媒体。
- 硬磁性ピニング層が、Coを主成分とし、CrおよびPtからなる群から選択される少なくとも1種をさらに含む材料からなることを特徴とする請求項1から4のいずれかに記載の垂直磁気記録媒体。
- 硬磁性ピニング層が、非磁性酸化物または非磁性窒化物のマトリクス中に磁性結晶粒子が分散されているグラニュラー構造を有する材料からなることを特徴とする請求項1から5のいずれかに記載の垂直磁気記録媒体。
- 硬磁性ピニング層が10nm以下の膜厚を有することを特徴とする請求項1から6のいずれかに記載の垂直磁気記録媒体。
- 硬磁性ピニング層の一軸異方性定数が5×105erg/cm3(5×104J/m3)以上であり、かつ保磁力が磁気記録層よりも低いことを特徴とする請求項1から7のいずれかに記載の垂直磁気記録媒体。
- 磁気記録層が、非磁性酸化物または非磁性窒化物のマトリクス中に磁性結晶粒子が分散されているグラニュラー構造を有する材料からなることを特徴とする請求項1から8のいずれかに記載の垂直磁気記録媒体。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006248628A JP4771222B2 (ja) | 2006-09-13 | 2006-09-13 | 垂直磁気記録媒体 |
SG200706335-7A SG141328A1 (en) | 2006-09-13 | 2007-08-27 | Perpendicular magnetic recording medium |
MYPI20071454A MY145525A (en) | 2006-09-13 | 2007-08-28 | Perpendicular magnetic recording medium |
US11/896,486 US7781080B2 (en) | 2006-09-13 | 2007-08-31 | Perpendicular magnetic recording medium |
CN2007101528039A CN101145351B (zh) | 2006-09-13 | 2007-09-12 | 垂直磁性记录介质 |
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JP2006248628A JP4771222B2 (ja) | 2006-09-13 | 2006-09-13 | 垂直磁気記録媒体 |
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JP2008071406A JP2008071406A (ja) | 2008-03-27 |
JP4771222B2 true JP4771222B2 (ja) | 2011-09-14 |
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US (1) | US7781080B2 (ja) |
JP (1) | JP4771222B2 (ja) |
CN (1) | CN101145351B (ja) |
MY (1) | MY145525A (ja) |
SG (1) | SG141328A1 (ja) |
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US8659852B2 (en) * | 2008-04-21 | 2014-02-25 | Seagate Technology Llc | Write-once magentic junction memory array |
US8045366B2 (en) * | 2008-11-05 | 2011-10-25 | Seagate Technology Llc | STRAM with composite free magnetic element |
US9093101B2 (en) | 2011-02-28 | 2015-07-28 | Seagate Technology Llc | Stack including a magnetic zero layer |
JP5768494B2 (ja) * | 2011-05-19 | 2015-08-26 | ソニー株式会社 | 記憶素子、記憶装置 |
JP7011477B2 (ja) * | 2017-03-07 | 2022-01-26 | 昭和電工株式会社 | アシスト磁気記録媒体及び磁気記憶装置 |
JP7107765B2 (ja) * | 2018-06-25 | 2022-07-27 | 昭和電工株式会社 | アシスト磁気記録媒体および磁気記憶装置 |
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JPH06103553A (ja) | 1992-09-18 | 1994-04-15 | Fujitsu Ltd | 垂直磁気記録媒体とその製造方法 |
JP2947029B2 (ja) | 1993-09-13 | 1999-09-13 | 日本ビクター株式会社 | 垂直磁気記録媒体 |
KR100371453B1 (ko) * | 1999-03-15 | 2003-02-06 | 가부시끼가이샤 도시바 | 자기 기록 장치 및 자기 기록 방법 |
JP4034485B2 (ja) | 1999-11-30 | 2008-01-16 | 株式会社東芝 | 磁気記録媒体 |
JP3340420B2 (ja) * | 2000-05-29 | 2002-11-05 | 株式会社日立製作所 | 垂直磁気記録媒体及び磁気記憶装置 |
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US6740398B2 (en) * | 2001-01-24 | 2004-05-25 | Seagate Technology Llc | Magnetic films including iridium, manganese and nitrogen |
US6835475B2 (en) * | 2001-07-26 | 2004-12-28 | Hitachi Global Storage Technologies Netherlands B.V. | Dual-layer perpendicular magnetic recording media with laminated underlayer formed with antiferromagnetically coupled films |
JP3911678B2 (ja) * | 2002-10-01 | 2007-05-09 | 富士通株式会社 | 多層垂直磁気記録媒体 |
JP2006018876A (ja) * | 2004-06-30 | 2006-01-19 | Toshiba Corp | 垂直磁気記録装置 |
JP4540557B2 (ja) | 2004-07-05 | 2010-09-08 | 富士電機デバイステクノロジー株式会社 | 垂直磁気記録媒体 |
US7588842B1 (en) * | 2004-09-02 | 2009-09-15 | Maxtor Corporation | Perpendicular magnetic recording medium with a pinned soft underlayer |
US20060147758A1 (en) * | 2005-01-06 | 2006-07-06 | Hong-Sik Jung | Perpendicular magnetic recording medium with magnetically resetable single domain soft magnetic underlayer |
JP2007026514A (ja) * | 2005-07-14 | 2007-02-01 | Hoya Corp | 垂直磁気記録媒体、及びその製造方法 |
JP2007273055A (ja) * | 2006-03-31 | 2007-10-18 | Fujitsu Ltd | 垂直磁気記録媒体および磁気記憶装置 |
-
2006
- 2006-09-13 JP JP2006248628A patent/JP4771222B2/ja active Active
-
2007
- 2007-08-27 SG SG200706335-7A patent/SG141328A1/en unknown
- 2007-08-28 MY MYPI20071454A patent/MY145525A/en unknown
- 2007-08-31 US US11/896,486 patent/US7781080B2/en active Active
- 2007-09-12 CN CN2007101528039A patent/CN101145351B/zh not_active Expired - Fee Related
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CN101145351A (zh) | 2008-03-19 |
US7781080B2 (en) | 2010-08-24 |
CN101145351B (zh) | 2011-04-13 |
US20080062583A1 (en) | 2008-03-13 |
JP2008071406A (ja) | 2008-03-27 |
MY145525A (en) | 2012-02-29 |
SG141328A1 (en) | 2008-04-28 |
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