TW495745B - Magnetic field element having a biasing magnetic layer structure - Google Patents

Magnetic field element having a biasing magnetic layer structure Download PDF

Info

Publication number
TW495745B
TW495745B TW089124262A TW89124262A TW495745B TW 495745 B TW495745 B TW 495745B TW 089124262 A TW089124262 A TW 089124262A TW 89124262 A TW89124262 A TW 89124262A TW 495745 B TW495745 B TW 495745B
Authority
TW
Taiwan
Prior art keywords
magnetic
layer structure
magnetic layer
field element
bias
Prior art date
Application number
TW089124262A
Other languages
English (en)
Inventor
Murray Fulton Gillies
Antonius Emilius Theodo Kuiper
Kars-Michiel Hubert Lenssen
Original Assignee
Koninkl Philips Electronics Nv
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 Koninkl Philips Electronics Nv filed Critical Koninkl Philips Electronics Nv
Application granted granted Critical
Publication of TW495745B publication Critical patent/TW495745B/zh

Links

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N50/00—Galvanomagnetic devices
    • H10N50/10—Magnetoresistive devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F10/00—Thin magnetic films, e.g. of one-domain structure
    • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
    • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
    • H01F10/3268—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the exchange coupling being asymmetric, e.g. by use of additional pinning, by using antiferromagnetic or ferromagnetic coupling interface, i.e. so-called spin-valve [SV] structure, e.g. NiFe/Cu/NiFe/FeMn
    • H01F10/3272—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the exchange coupling being asymmetric, e.g. by use of additional pinning, by using antiferromagnetic or ferromagnetic coupling interface, i.e. so-called spin-valve [SV] structure, e.g. NiFe/Cu/NiFe/FeMn by use of anti-parallel coupled [APC] ferromagnetic layers, e.g. artificial ferrimagnets [AFI], artificial [AAF] or synthetic [SAF] anti-ferromagnets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y25/00—Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
    • G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
    • G01R33/09—Magnetoresistive devices
    • G01R33/093—Magnetoresistive devices using multilayer structures, e.g. giant magnetoresistance sensors
    • 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
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
    • 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
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
    • G11B5/3906—Details related to the use of magnetic thin film layers or to their effects
    • G11B5/3909—Arrangements using a magnetic tunnel junction
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
    • G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
    • G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
    • G11C11/161—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F10/00—Thin magnetic films, e.g. of one-domain structure
    • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
    • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
    • H01F10/3254—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F10/00—Thin magnetic films, e.g. of one-domain structure
    • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
    • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
    • H01F10/3263—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the exchange coupling being symmetric, e.g. for dual spin valve, e.g. NiO/Co/Cu/Co/Cu/Co/NiO
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F10/00—Thin magnetic films, e.g. of one-domain structure
    • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
    • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
    • H01F10/3268—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the exchange coupling being asymmetric, e.g. by use of additional pinning, by using antiferromagnetic or ferromagnetic coupling interface, i.e. so-called spin-valve [SV] structure, e.g. NiFe/Cu/NiFe/FeMn
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10B—ELECTRONIC MEMORY DEVICES
    • H10B61/00—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
    • H10B61/10—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices comprising components having two electrodes, e.g. diodes or MIM elements
    • 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
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B2005/3996—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Power Engineering (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • General Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Hall/Mr Elements (AREA)
  • Mram Or Spin Memory Techniques (AREA)
  • Magnetic Heads (AREA)
  • Thin Magnetic Films (AREA)
  • Semiconductor Memories (AREA)

Description

495745 _案號89124262 f/年^月丨Γ日_^__ 五、發明說明（1) 發明領域 本發明關於備有堆壘之第一磁層結構，及具有固定磁向 之第二磁層結構之磁場元件，及一隔片層結構將第一磁層 與第二磁層彼此分開，磁場元件尚備有偏壓裝置以施加一 縱向偏壓場至第一磁層結構。縱向偏壓場垂直導向第二磁 層結構之固定磁向。 發明背景 磁場元件曾揭示於美國專利號碼U S - A 5，7 2 9，4 1 0中。該 已知磁場元件被用做為一感測器，以讀出磁記錄之資料， 其尚有一在絕緣隧道屏蔽層相反侧之固定鐵磁層及一感測 鐵磁層。硬偏壓鐵磁材料之二層部份，一種钻始鉻合金-， 位於感測層之側邊緣附近，但分開。該層部份與感測鐵磁 層為電絕緣，但與其為磁耦合，並作為此感測層之磁矩之 縱向偏壓。已知偵測器之缺點為，硬偏壓材料之層部份甚 難控制，故僅對大執道寬度較為實際，因該磁鐵遠離，其 合成磁場為一低值，即5 -1 0 0 e，並切為同性。對高密度 記錄而言，其並非適合答案。已知感測器之另一缺點為， 該層部份為一材料製成，該材料未在感測器其他部份使 用。因此需要澱積系統之額外來源。此外，在製造期間限 定該層部份結構時，需要調額外之屏罩步驟。此外，硬磁 材料常顯出強溫度依存性。 發明簡要說明 本發明之目的為提供上述種類之一改進之磁場元件，其 方式為偏壓裝置為簡單，但能提供極高密度應用之適當答 案0
O:\67\67634.ptc 第5頁 495745 _案號 89124262 f / 年 $ 月 & 日_||i__ 五、發明說明（2) 此目的可由本發明之磁場元件達成，其特徵為偏壓裝置 包括一偏壓磁層，位於第一磁層結構之對侧，該偏壓磁層 結構提供一磁耦合場成份，與第二磁層結構之磁向垂直， 並由一磁層結構將其自第一磁層結構分開。所用之方法在 偏壓磁層結構與第一磁層結構間，造成一磁耦合通過非磁 層結構。在磁場元件之製造期間，偏壓磁層結構可利用簡 單方式以現有技術實現。在偏壓磁層結構形成期間，應加 一磁場，該磁場較第二磁層結構形成期間所加之磁場之角 大於0度，小於1 8 0度。 本發明之磁場元件可為一旋轉隧道接合元件，此情況 時，隔片層結構包括一絕緣材料隧道屏蔽層，如三氧I二 鋁，或大磁阻型旋轉閥元件。此二情形下，一極重要之磁 特性為第一磁層結構之磁滯。當此層結構之磁矩與磁源， 即通過之磁碟之磁場對齊時，可達成一與第二磁層結構之 磁矩之反平行。此效應產生電阻之改變。為防止磁場元件 輸出之失真，必須防止引入疇壁，在磁校正期間，通過第 一磁層結構移動。如磁滞存在於第一磁層結構時，缚壁可 能被引入。已證明在本發明之感測器中之磁滯已大幅降 低，或已完全消除。 本發明之磁場元件中，一磁耦場，即一縱向偏壓場位於 偏壓磁層結構與第一磁層結構之間，該磁耦合為一靜磁 場，並僅限定於局部位準，即僅為結構之粒子大小。因此 可使一較低之磁場加在其上，較硬磁材料之層部份之磁場 為小。本發明磁場元件之另一優點為，由於耦合磁場之局 部性，其均勻性較佳，並與磁場元件之尺寸及環境無關。
O:\67\67634.ptc 第6頁 495745 _案號 89124262 〒/年》月β曰 修正__ 五、發明說明（3) 通常，第一磁層結構有一磁化之易軸（Easy Axis)，與 第二磁層結構之固定磁向成垂直。第一磁層結構包含一鐵 磁材料之鐵磁層，如錄鐵合金或始鐵合金，此鐵磁層被稱 為自由層。第二磁層結構包含鐵層材料之固定磁，如鎳鐵 合金，或鎳鈷合金，被稱為交換偏壓材料之固定磁，如反 鐵磁材料，即銥錳合金。 本發明磁場元件之一實施例之特徵為，偏壓磁層結構有 一固定磁向，此磁向與第二磁層結構之磁向至少成45度 角，最大成1 3 5度角。在此較佳實施例中，偏壓磁層結構 對第一磁層結構有一明顯效應，意即在第一磁層結構中之 磁滯已大幅降低。本實施例中可達成一最大縱向偏壓敗 場’其特徵為’偏壓磁層之磁向與第二磁層結構之磁向成 9 0度角。 本發明磁場元件之實施例中，非磁層結構包括一或多層 銅，釕及組及/或非磁氧化物，如三氧化二紹。如調整此 層之厚度，縱向偏壓場可被調諧，自厚銅層之5 0 e至薄銅 層之數百Oe。在旋轉閥元件中，以钽較佳，因為其高電阻 率之故。此外，钽可導出理想晶體組織。 本發明之磁場元件之一實施例之特徵為，偏壓磁層結構 包括一被固定層結構及一固定層結構，以固定被固定層結 構。被固定層結構較佳包括磁材料之鐵磁層，如，錄鐵合 金，始或銘鐵合金。 本發明磁場元件上述實施例之較佳特徵為固定層結構包 括，交換偏壓材料層，如反鐵磁材料，即鐵錳合金，銥錳 合金，或鐵磁材料，即铽鈷合金或铽鐵鈷合金。
O:\67\67634.ptc 第7頁 495745 _案號89124262 夕/年孓月，广曰 修正_— 五、發明說明（4) 如必要時，被固定層界結構可含二鐵磁層由一非磁性材 料層分開。此結構可為鐵磁材料之二層，如鎳鐵合金，或 始鐵合金，及一中間插入之非磁性材料層，如釕，銖或 銅。中間插入層導致一反鐵磁搞合於鐵磁材料磁之間。該 結構含鐵磁材料層，由一非磁材料層中間插入，通常稱為 人工反鐵磁（AAF)。 本發明磁場元件之一實施例之特徵如申請專利範圍第8 項所限定。此實施例中，磁雜散場可為最小。 本發明之磁場元件之實施例之特徵為，如申請專利範圍 第9項所限定。偏壓磁層結構之磁強度，在此實施例中得 以進一步改進。 — 本發明尚關於一含磁場元件之旋轉隧道接面裝置。本發 明之旋轉隧道接面裝置，備有本發明之磁場元件，隔片層 結構包括絕緣材料如三氧化二铭之隧道屏蔽層。 本發明尚關於一含磁場元件之大磁阻裝置。本發明之大 磁阻裝置包括本發明之磁場元件。一種絕緣材料如三氧化 二紹，或高電阻率之材料如组，鐫或19為非磁層之較佳材 料。 以上所提之裝置均可作為感測器，及場感測器供汽車應 用或磁頭之用，與磁登錄或資訊媒體合作。 本發明尚關於自磁資訊載體讀出資訊之系統，系統包括 本發明之磁場元件，或本發明之一裝置。 本發明尚關於一含本發明之磁場元件之磁記憶體，及關 於含該記憶體之電子電路。 參考申請專利範圍，應注意，申請範圍定義之不同特
O:\67\67634.ptc 第8頁 495745 _案號 89124262 fY 年 > 月 f 日___ 五、發明說明（5) 徵，均可以組合方式產生。此外，π層結構"一詞，在本文 件中可意指單層或一堆疊層。 圖式簡要說明 本發明上述特性將可自以下非限制舉例說明，及參考圖 式得以更為明顯。 圖中： 圖1為本發明磁場元件之實施例之剖面圖， 圖2為本發明之大磁阻型旋轉閥元件之實施例之剖面 圖， 圖3為本發明旋轉隧道接面裝置之實施例之剖面圖， 圖4為本發明備有磁場元件之磁場感測器之實施例之立 體圖， 圖5為本發明一系統之實施例圖解， 圖6為本發明一磁記憶體之一實施例之剖面圖， 圖7為本發明一電子電路之圖解。 值得注意的是使用相同參考符號來表示數個實施例中之 相對應部份。 圖式元件符號說明 1 基 體 3 偏 壓 磁 層 結 構 3Α 固 定 層 結 構 3Β 被 固 定 層 結 構 3Β, 鐵 磁 材 料 層 3Β2 鐵 磁 材 料 層 3Β3 插 入 層
O:\67\67634.ptc 第9頁 495745 修正 案號 89124262 f /年+月f曰 五、發明說明（6) 5 非 磁 層 結 構 7 第 一一 磁層 結 構 9 隔 片 層 結 構 11 第 二 磁 層 結 構 1 1 A 被 固 定 層 1 1B 固 定 層 100 電連接 1 0 2 磁 力 線 導 引 1 02a 端 面 104 磁 力 線 導 引 104a 端 面 106 磁 隙 200 框 架 20 2 轴 心 204 磁碟 資 訊 載 體 206 搖 臂 208 磁 場 感 測 器 300 旋轉隧道接點裝置 302 半導體 400 平 面 圖 402 選 擇 裝 置 404 磁 組 件 八7 磁 化 易 轴 m3 磁 向 Μη 磁 向
O:\67\67634.ptc 第10頁 495745 _案號89124262 年多月仏曰 修正__ 五、發明說明（7) T 電晶體 發明詳細說明 圖1之磁場元件備有由基體1支撐之一堆疊，實際上平行 之層結構。此堆疊層結構順序包含一偏壓磁層結構3，一 非磁結構5，第一磁層結構7，一隔片層結構9及第二磁層 結構1 1。基體1可由一非磁，非導體材料如矽組成。第一 磁層結構7及第二磁層結構1 1將隔片結構9夾在其間，偏壓 磁層結構3及第一磁層結構7將非磁層結構5加在其間。每 一層結3，5，7，9及11可含單一層或多層。第二磁層結構 11有一固定磁向Μη於層結構11之平面中。磁向Mu在製造期 間，基一適當磁場，在形成時，特別是第二磁層結構1 L形 成時加上。 偏壓磁層結構3，位於第一磁層結構7之對面，其有一磁 化心，其提供一與磁化M3平行，及與第二磁層結構11之磁 向心1垂直之搞合磁場成份。磁向1在形成時實現’特別在 偏壓磁層結構3之澱積時實現，方式為施加一適當磁場， 其使在第二磁層結構1 1形成時，與所加之磁場成0度至1 8 0 度角。磁向M3經由非磁層結構5，產生一磁耦合於偏壓磁層 結構3與第一磁層結構7之間，該耦合為一非常局部之靜磁 I禺合。較佳為，偏壓磁層結構3之磁向M3有一固定方向，該 方向與第二磁層結構11之磁向Μπ成至少45度至135度角。 如偏壓磁層結構之磁向Μ3與磁向Μη成9 0度則最大磁耦合場 可以達成。第一磁層結構7有一磁化易轴Α7，與第二磁層結 構1 1之固定磁向Μη平行。或者，某些應用中，最好使磁化 易轴Α7與固定磁向Mu垂直。第一磁層結構7可包括一自由
O:\67\67634.ptc 第11頁 495745 _案號89124262 7/ 年多月（厂日__ 五、發明說明（8) 層，其由鐵磁材料，NixFei_x組成。第二磁層結構1 1包括所 謂鐵磁材料之被固定層，如CoxF ei_x，或交換偏壓材料之被 固定層，如反鐵磁材料，即，F e 5 〇 Μ η 5 〇。 本發明磁場元件可用於旋轉隧道接面裝置中，此情況 下，隔片層結構9包括一電絕緣材料，如三氧化二鋁之隧 道屏蔽層，或用於大磁阻裝置中，此時，隔片層結構9包 括非磁材料層，如銅非磁材料層。 非磁層結構5可含一層或多層非磁材料銅，銥，钽或氧 化物三氧化二鋁，或其他適合之非磁材料。偏壓磁層結構 3可包括一被固定層結構之堆疊，及一固定層結構。被固 定層結構較佳含二層鐵磁材料層，如鎳鐵合金，由一層-非 磁材料如銅分隔，固定層結構較佳含一交換偏壓材料層， 如鐵猛合金，或適當鐵磁材料如錢始合金。較佳為一鐵磁 層鄰近交換偏壓材料層。或者，偏壓層結構3包括二鐵磁 材料層，由非磁材料層分開。 圖2之大磁阻裝置可含一基體及含一備有含偏壓層結構 3，非磁層結構5，第一磁層結構7，隔片層結構9及第二磁 層結構1 1之層結構堆疊。偏壓層結構3有一磁向Μ3，其與第 二磁層結構1 1之固定磁向Μη成垂直。偏壓磁層3含一被導 向層結構3 Β，及一導向層結構3 Α以固定結構3 Β。固定層3 A 包括一交換偏壓材料層，此實施例中為銥錳合金。此實施 例中，被固定層結構3 B含二層鐵磁材料之3 Bi及3 B2，由一 非磁材料之插入層3 B3分開。鐵磁材料為鈷鐵合金，此實施 例中之非磁材料為銖。層3 Bi，3 B2及3 B3之結構導致一反鐵 磁耦鐵磁層3 Bi與3 B2之間。在此實施例中，非磁層結構5含
O:\67\67634.ptc 第12頁 495745 案號 89124262 #年彡月 修正 五、發明說明（9) 一钽層。第一磁層結構7包括鐵磁材料之自由層，即鎳鐵 合金。隔片層結構9含一銅層。第二磁層結構1 1為被固定 結構，具有被固定層1 1 Α及固定層1 1 Β。第二磁層結構1 1有 其固定磁向Mn，偏壓磁層結構3提供一磁合場成份向Μπ垂 直。 圖3顯示旋轉接面裝置中包含，備於基體1上之磁場元 件，並備有一堆疊偏壓磁層結構3也非磁層結構5，第一磁 層結構7，隔片層結構9及第二磁層結構1 1。隔片層結構9 包括非磁，電絕緣材料如適當之氧化物，三氧化二鋁之隧 道屏蔽層。層結構3，5及1 1可如本實施例所述方式組成。 圖4顯示磁場感測器之一部份。此感測器含具有電連接 1 0 0之換能器Τ。換能器Τ包括一本發明之磁場元件之實施 例，即圖1至3所示之實施例。此感測器包含磁力線固定 102及104，其配置於與Τ相對位置，以形成一磁電路。磁 力線固定102及104各有一端面102a及104a形成一極，面向 感測器，一磁隙1 0 6位於二表面之間。如一磁媒體如磁 滯，磁碟或磁卡通過二面102a及104a之附近，在媒體上儲 存之貧訊在上述之磁電路中產生改變之磁力線’該磁力線 亦饋入換能器T中。換能器T將改變之磁力線轉換為電阻變 化，其可由適當連接至電連接1 0 0之測量儀器所測量。此 一感測器，亦稱為磁頭，亦可含一感應線圈，其可用於磁 資訊之記錄於磁媒體上。 圖5顯示本發明之系統，其包括框架2 0 0及一軸心2 0 2， 其可旋轉安裝在框架200上，以載負一磁碟資訊載體204， 如硬碟或磁光碟。資訊載體204可為一整合載體，或可移
O:\67\67634.ptc 第13頁 495745 _案號89124262 f/年 > 月 < 日 修正_. 五、發明說明（10) - 動載體。系統尚含一搖臂2 0 6，載負本發明之磁場感測器 2 0 8。備有驅動機以驅動軸心2 0 2及搖臂2 0 6。作業時，感 測器2 0 8掃描旋轉資訊載體2 0 4，感測器被置於資訊載體 · 2 0 4之對側，並沿徑向與載體2 0 4作相對移動。顯示之系統 . 為一資料儲存系統，亦可為一音頻及/或視頻系統。本發 明之系統亦可為自一磁帶或磁卡讀取資訊之系統。 圖6為本發明之旋轉隧道接面裝置300，其統合於一半導 體302之上’如電晶體’即碎電晶體’或二極體’即GaAs 二極體，其形成一高密度非易失性單元。 . 圖7顯示一高密度MRAM之平面圖400。平面圖400包括含 選擇裝置4 0 2，即二極體或電晶體之記憶體單元，及一磁 _ 組件4 0 4，其形式為本發明之隧道接面裝置，或本發明之 大磁阻裝置。
O:\67\67634.ptc 第14頁 495745 _案號89124262 年j月曰_修正 圖式簡單說明 第15頁 O:\67\67634.ptc

Claims (1)

  1. 495745 _案號 89124262 年多月 日___ 六、申請專利範圍 1 . 一種磁場元件，具有一堆疊之第一磁層結構、一第 二磁層結構，其具有一固定磁向、及一隔片結構，該隔片 結構用以將該第一磁層結構及該第二磁層結構彼此分開， 該磁場元件尚具備有一偏壓機構，用以施加一縱向偏壓場 至該第一磁層結構，其特徵為，該偏壓機構包含一偏壓磁 層結構，其位於該第一磁層結構之對面，該偏壓磁層結構 提供一磁耦合場成份，其與該第二磁層結構之磁向成垂 直，並與該第一磁層結構以一非磁層結構分開。 2. 如申請專利範圍第1項之磁場元件，其特徵為，該偏 壓磁層結構有一固定磁向，與該第二磁層結構之磁向成至 少45度及最大135度角。 — 3. 如申請專利範圍第2項之磁場元件，其特徵為，該偏 壓磁層結構之磁向與該第二磁層結構之磁向成90度角。 4. 如申請專利範圍第1項之磁場元件，其特徵為，該非 磁結構包括一铽層。 5. 如申請專利範圍第1項之磁場元件，其特徵為，該偏 壓磁層結構包括一被固定之層結構及一固定層結構，以供 固定該被固定層磁結構。 6. 如申請專利範圍第5項之磁場元件，其特徵為，該固 定層結構包括一交換偏壓材料層。 7. 如申請專利範圍第5項之磁場元件，其特徵為，該被 固定層結構包括二鐵磁層，其由一非磁材料層分開。 8. 如申請專利範圍第1項之磁場元件，其特徵為，該偏 壓磁層結構包括二鐵磁層，其由一非磁材料層分開。
    O:\67\67634.ptc 第16頁 495745 案號 89124262 f/年j 月曰 修正 六、申請專利範圍 9. 如申請專利範圍第6項之磁場元件，其特徵為，該偏 壓磁層結構包括二鐵磁層，其由一非磁材料層分開，其中 一鐵磁層與該交換偏壓材料層鄰近。 10. —種旋轉隧道接面裝置，其包含一磁場元件，該磁 場元件具有一堆疊之第一磁層結構、一第二磁層結構，其 具有一固定磁向、及一隔片結構，該隔片層結構包括一隧 道屏蔽層，該隔片結構用以將該第一磁層結構及該第二磁 層結構彼此分開，該磁場元件尚具備有一偏壓機構，用以 施加一縱向偏壓場至該第一磁層結構，其特徵為，該偏壓 機構包含一偏壓磁層結構，其位於該第一磁層結構之對
    面，該偏壓磁層結構提供一磁耦合場成份，其與該第二磁 層結構之磁向成垂直，並與該第一磁層結構以一非磁層結 構分開。
    11. 一種大磁阻裝置，其包含一磁場元件，該磁場元件 具有一堆疊之第一磁層結構、一第二磁層結構，其具有一 固定磁向、及^一隔片結構’該隔片結構用以將該第一磁層 結構及該第二磁層結構彼此分開，該磁場元件尚具備有一 偏壓機構，用以施加一縱向偏壓場至該第一磁層結構，其 特徵為，該偏壓機構包含一偏壓磁層結構，其位於該第一 磁層結構之對面，該偏壓磁層結構提供一磁耦合場成份， 其與該第二磁層結構之磁向成垂直，並與該第一磁層結構 以一非磁層結構分開。 12. —種自磁資訊載體讀出資訊之系統，該系統包括一 磁場元件，該磁場元件具有一堆疊之第一磁層結構、一第
    O:\67\67634.ptc 第17頁 495745 _案號89124262 9(年；月丨’曰_ί±^_ 六、申請專利範圍 二磁層結構，其具有一固定磁向、及一隔片結構，該隔片 結構用以將該第^一磁層結構及該第二磁層結構彼此分開’ 該磁場元件尚具備有一偏壓機構，用以施加一縱向偏壓場 至該第一磁層結構，其特徵為，該偏壓機構包含一偏壓磁 層結構，其位於該第一磁層結構之對面，該偏壓磁層結構 提供一磁耦合場成份，其與該第二磁層結構之磁向成垂 直，並與該第一磁層結構以一非磁層結構分開。 13. —種磁記憶體，其包括一磁場元件，該磁場元件具 有一堆疊之第一磁層結構、一第二磁層結構，其具有一固 定磁向、及一隔片結構，該隔片結構用以將該第一磁層結 構及該第二磁層結構彼此分開，該磁場元件尚具備有一·偏 壓機構，用以施加一縱向偏壓場至該第一磁層結構，其特 徵為，該偏壓機構包含一偏壓磁層結構，其位於該第一磁 層結構之對面，該偏壓磁層結構提供一磁耦合場成份，其 與該第二磁層結構之磁向成垂直，並與該第一磁層結構以 一非磁層結構分開。 14. 一種電子電路，其包括一磁記憶體，該磁記憶體包 括一磁場元件，該磁場元件具有一堆疊之第一磁層結構、 一第二磁層結構，其具有一固定磁向、及一隔片結構，該 隔片結構用以將該第一磁層結構及該第二磁層結構彼此分 開，該磁場元件尚具備有一偏壓機構，用以施加一縱向偏 壓場至該第一磁層結構，其特徵為，該偏壓機構包含一偏 壓磁層結構，其位於該第一磁層結構之對面，該偏壓磁層 結構提供一磁耦合場成份，其與該第二磁層結構之磁向成
    O:\67\67634.ptc 第18頁 495745 _案號 89124262 分年j月/广曰 修正_ 六、申請專利範圍 垂直，並與該第一磁層結構以一非磁層結構分開。
    O:\67\67634.ptc 第19頁
TW089124262A 2000-03-09 2000-11-16 Magnetic field element having a biasing magnetic layer structure TW495745B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP00200830 2000-03-09

Publications (1)

Publication Number Publication Date
TW495745B true TW495745B (en) 2002-07-21

Family

ID=8171169

Family Applications (1)

Application Number Title Priority Date Filing Date
TW089124262A TW495745B (en) 2000-03-09 2000-11-16 Magnetic field element having a biasing magnetic layer structure

Country Status (7)

Country Link
US (1) US6438026B2 (zh)
EP (1) EP1200972A1 (zh)
JP (1) JP2003526913A (zh)
KR (1) KR20020019017A (zh)
CN (1) CN1242429C (zh)
TW (1) TW495745B (zh)
WO (1) WO2001067469A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6950333B2 (en) 2001-06-19 2005-09-27 Matsushita Electric Industrial Co., Ltd. Magnetic memory and method for driving the same, and magnetic memory device using the same

Families Citing this family (63)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3817399B2 (ja) * 1999-12-24 2006-09-06 株式会社日立グローバルストレージテクノロジーズ 磁気抵抗センサー
US6791805B2 (en) * 2001-05-03 2004-09-14 Seagate Technology Llc Current-perpendicular-to-plane spin valve reader with reduced scattering of majority spin electrons
US6744086B2 (en) 2001-05-15 2004-06-01 Nve Corporation Current switched magnetoresistive memory cell
US6631055B2 (en) * 2001-06-08 2003-10-07 International Business Machines Corporation Tunnel valve flux guide structure formed by oxidation of pinned layer
US6757144B2 (en) * 2002-01-18 2004-06-29 International Business Machines Corporation Flux guide read head with in stack biased current perpendicular to the planes (CPP) sensor
US6865062B2 (en) * 2002-03-21 2005-03-08 International Business Machines Corporation Spin valve sensor with exchange biased free layer and antiparallel (AP) pinned layer pinned without a pinning layer
US6741432B2 (en) * 2002-03-21 2004-05-25 International Business Machines Corporation Current perpendicular to the planes (CPP) spin valve sensor with in-stack biased free layer and self-pinned antiparallel (AP) pinned layer structure
US6856493B2 (en) * 2002-03-21 2005-02-15 International Business Machines Corporation Spin valve sensor with in-stack biased free layer and antiparallel (AP) pinned layer pinned without a pinning layer
JP2003281705A (ja) * 2002-03-25 2003-10-03 Hitachi Ltd 磁気ヘッド、磁気ヘッドジンバルアッセンブリ、磁気記録再生装置及び磁性メモリ
US6801412B2 (en) 2002-04-19 2004-10-05 International Business Machines Corporation Method and apparatus for improved pinning strength for self-pinned giant magnetoresistive heads
US7170721B2 (en) * 2002-06-25 2007-01-30 Quantum Corporation Method of producing flux guides in magnetic recording heads
US6781798B2 (en) 2002-07-15 2004-08-24 International Business Machines Corporation CPP sensor with dual self-pinned AP pinned layer structures
US6654278B1 (en) * 2002-07-31 2003-11-25 Motorola, Inc. Magnetoresistance random access memory
US6677631B1 (en) * 2002-08-27 2004-01-13 Micron Technology, Inc. MRAM memory elements and method for manufacture of MRAM memory elements
US6881993B2 (en) * 2002-08-28 2005-04-19 Micron Technology, Inc. Device having reduced diffusion through ferromagnetic materials
US6937448B2 (en) * 2002-11-13 2005-08-30 Hitachi Global Storage Technologies Netherlands, B.V. Spin valve having copper oxide spacer layer with specified coupling field strength between multi-layer free and pinned layer structures
US6947264B2 (en) * 2002-12-06 2005-09-20 International Business Machines Corporation Self-pinned in-stack bias structure for magnetoresistive read heads
KR100499136B1 (ko) * 2002-12-14 2005-07-04 삼성전자주식회사 전자 스핀의존 산란을 이용한 자성매체 및 자성매체정보재생장치 및 재생방법
US6829161B2 (en) * 2003-01-10 2004-12-07 Grandis, Inc. Magnetostatically coupled magnetic elements utilizing spin transfer and an MRAM device using the magnetic element
US6867953B2 (en) * 2003-07-02 2005-03-15 Hitachi Global Storage Technologies Netherlands B.V. Self-pinned in-stack bias structure with improved pinning
US6920062B2 (en) * 2003-10-14 2005-07-19 International Business Machines Corporation System and method for reading data stored on a magnetic shift register
US20050105328A1 (en) * 2003-11-17 2005-05-19 Ho Chiahua Perpendicular MRAM with high magnetic transition and low programming current
US6967863B2 (en) * 2004-02-25 2005-11-22 Grandis, Inc. Perpendicular magnetization magnetic element utilizing spin transfer
US7301735B2 (en) * 2004-03-15 2007-11-27 Hitachi Global Technologies Netherlands B.V. Higher flip threshold structure for in-stack bias layer
US7339818B2 (en) * 2004-06-04 2008-03-04 Micron Technology, Inc. Spintronic devices with integrated transistors
US7576956B2 (en) * 2004-07-26 2009-08-18 Grandis Inc. Magnetic tunnel junction having diffusion stop layer
US7290325B2 (en) 2004-08-13 2007-11-06 Quantum Corporation Methods of manufacturing magnetic heads with reference and monitoring devices
US7446986B2 (en) * 2004-08-31 2008-11-04 Hitachi Global Storage Technologies Netherlands B.V. Magnetic tunnel junction with in stack biasing layer providing orthogonal exchange coupling
US7236386B2 (en) * 2004-12-04 2007-06-26 International Business Machines Corporation System and method for transferring data to and from a magnetic shift register with a shiftable data column
US7636223B2 (en) * 2005-01-10 2009-12-22 Hitachi Global Storage Technologies Netherlands B.V. Three terminal magnetic sensor having an in-stack longitudinal biasing layer structure and a self-pinned layer structure
US7259942B2 (en) * 2005-01-10 2007-08-21 Hitachi Global Storage Technologies Netherlands B.V. Three terminal magnetic sensor having an in-stack longitudinal biasing layer structure in the collector or emitter region
US7639459B2 (en) * 2005-01-10 2009-12-29 Hitachi Global Storage Technologies Netherlands B.V. Three terminal magnetic sensor having an in-stack longitudinal biasing layer structure
US7710691B2 (en) * 2005-01-10 2010-05-04 Hitachi Global Storage Technologies Netherlands B.V. Three terminal magnetic sensor having an in-stack longitudinal biasing layer structure in the collector region and a pinned layer structure in the emitter region
KR100647319B1 (ko) * 2005-02-05 2006-11-23 삼성전자주식회사 스핀 분극 전류를 이용한 멀티 비트 자기 메모리 소자와그 제조 및 구동 방법
US7285836B2 (en) * 2005-03-09 2007-10-23 Maglabs, Inc. Magnetic random access memory with stacked memory cells having oppositely-directed hard-axis biasing
US7443638B2 (en) * 2005-04-22 2008-10-28 Taiwan Semiconductor Manufacturing Company Ltd. Magnetoresistive structures and fabrication methods
US7751154B2 (en) * 2005-05-19 2010-07-06 Quantum Corporation Magnetic recording heads with bearing surface protections and methods of manufacture
US7518835B2 (en) * 2005-07-01 2009-04-14 Grandis, Inc. Magnetic elements having a bias field and magnetic memory devices using the magnetic elements
US7397638B2 (en) * 2005-07-22 2008-07-08 Hitachi Global Storage Technologies Netherlands B.V. Magnetoresistive sensor having an in stack bias structure with NiFeCr spacer layer for improved bias layer pinning
US7230845B1 (en) 2005-07-29 2007-06-12 Grandis, Inc. Magnetic devices having a hard bias field and magnetic memory devices using the magnetic devices
US7777261B2 (en) * 2005-09-20 2010-08-17 Grandis Inc. Magnetic device having stabilized free ferromagnetic layer
US7859034B2 (en) * 2005-09-20 2010-12-28 Grandis Inc. Magnetic devices having oxide antiferromagnetic layer next to free ferromagnetic layer
US7973349B2 (en) * 2005-09-20 2011-07-05 Grandis Inc. Magnetic device having multilayered free ferromagnetic layer
US7430135B2 (en) * 2005-12-23 2008-09-30 Grandis Inc. Current-switched spin-transfer magnetic devices with reduced spin-transfer switching current density
US20070246787A1 (en) * 2006-03-29 2007-10-25 Lien-Chang Wang On-plug magnetic tunnel junction devices based on spin torque transfer switching
US20070297220A1 (en) * 2006-06-22 2007-12-27 Masatoshi Yoshikawa Magnetoresistive element and magnetic memory
US7851840B2 (en) * 2006-09-13 2010-12-14 Grandis Inc. Devices and circuits based on magnetic tunnel junctions utilizing a multilayer barrier
US8378329B2 (en) * 2007-03-02 2013-02-19 Brookhaven Science Associates, Llc Nanodevices for spintronics and methods of using same
US7957179B2 (en) * 2007-06-27 2011-06-07 Grandis Inc. Magnetic shielding in magnetic multilayer structures
US20090027948A1 (en) * 2007-07-24 2009-01-29 Manfred Ruehrig Integrated Circuits, Method of Programming a Cell, Thermal Select Magnetoresistive Element, Memory Module
US20090046502A1 (en) * 2007-08-16 2009-02-19 Northern Lights Semiconductor Corp. Metal Magnetic Memory Cell
US7982275B2 (en) * 2007-08-22 2011-07-19 Grandis Inc. Magnetic element having low saturation magnetization
US7894248B2 (en) * 2008-09-12 2011-02-22 Grandis Inc. Programmable and redundant circuitry based on magnetic tunnel junction (MTJ)
KR20100041155A (ko) * 2008-10-13 2010-04-22 삼성전자주식회사 저항성 메모리 소자
US8579203B1 (en) * 2008-12-19 2013-11-12 Dynamics Inc. Electronic magnetic recorded media emulators in magnetic card devices
FR2945147B1 (fr) * 2009-04-30 2012-03-30 Thales Sa Dispositif memristor a resistance ajustable grace au deplacement d'une paroi magnetique par transfert de spin et utilisation dudit memristor dans un reseau de neurones
US8580580B2 (en) * 2010-04-01 2013-11-12 Seagate Technology Llc Magnetic element with varying areal extents
CN102270736B (zh) * 2010-06-01 2014-02-05 中国科学院物理研究所 一种用于磁敏传感器的磁性纳米多层膜及其制造方法
US8829901B2 (en) * 2011-11-04 2014-09-09 Honeywell International Inc. Method of using a magnetoresistive sensor in second harmonic detection mode for sensing weak magnetic fields
WO2016122402A1 (en) * 2015-01-27 2016-08-04 Agency for Science,Technology and Research Magnetoresistive device and method of forming the same
EP3104187A1 (en) * 2015-06-09 2016-12-14 International Iberian Nanotechnology Laboratory Magnetoresistive sensor
US10680570B2 (en) * 2017-09-08 2020-06-09 Tdk Corporation Magnetoresistance effect device and high frequency device
US10937828B2 (en) 2018-10-11 2021-03-02 International Business Machines Corporation Fabricating embedded magnetoresistive random access memory device with v-shaped magnetic tunnel junction profile

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4243358A1 (de) * 1992-12-21 1994-06-23 Siemens Ag Magnetowiderstands-Sensor mit künstlichem Antiferromagneten und Verfahren zu seiner Herstellung
US5729410A (en) 1996-11-27 1998-03-17 International Business Machines Corporation Magnetic tunnel junction device with longitudinal biasing
US6023395A (en) * 1998-05-29 2000-02-08 International Business Machines Corporation Magnetic tunnel junction magnetoresistive sensor with in-stack biasing
US6252796B1 (en) * 1998-08-14 2001-06-26 U.S. Philips Corporation Device comprising a first and a second ferromagnetic layer separated by a non-magnetic spacer layer
US6259586B1 (en) * 1999-09-02 2001-07-10 International Business Machines Corporation Magnetic tunnel junction sensor with AP-coupled free layer
US6266218B1 (en) * 1999-10-28 2001-07-24 International Business Machines Corporation Magnetic sensors having antiferromagnetically exchange-coupled layers for longitudinal biasing

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6950333B2 (en) 2001-06-19 2005-09-27 Matsushita Electric Industrial Co., Ltd. Magnetic memory and method for driving the same, and magnetic memory device using the same

Also Published As

Publication number Publication date
CN1242429C (zh) 2006-02-15
KR20020019017A (ko) 2002-03-09
WO2001067469A1 (en) 2001-09-13
EP1200972A1 (en) 2002-05-02
CN1364300A (zh) 2002-08-14
JP2003526913A (ja) 2003-09-09
US20010026470A1 (en) 2001-10-04
US6438026B2 (en) 2002-08-20

Similar Documents

Publication Publication Date Title
TW495745B (en) Magnetic field element having a biasing magnetic layer structure
US6515573B1 (en) Method and system for providing edge-junction TMR utilizing a hard magnet as a pinned layer
US5936810A (en) Magnetoresistive effect head
US5898548A (en) Shielded magnetic tunnel junction magnetoresistive read head
US6005753A (en) Magnetic tunnel junction magnetoresistive read head with longitudinal and transverse bias
US8077435B1 (en) Current perpendicular-to-plane read sensor with back shield
US6456467B1 (en) Laminated shields with antiparallel magnetizations
US7522392B2 (en) Magnetoresistive sensor based on spin accumulation effect with terminal connection at back end of sensor
US5729410A (en) Magnetic tunnel junction device with longitudinal biasing
US6469873B1 (en) Magnetic head and magnetic storage apparatus using the same
CN100435372C (zh) 沉积有氧化物磁性层和金属磁性膜的磁致电阻元件
US7453671B1 (en) Magnetic head having a pair of magneto-resistive (MR) readers of the same type with each reader being tuned differently
JPH1011723A (ja) 磁気抵抗効果型トランスデューサ、その製造方法及び磁気記録装置
US6876522B2 (en) GMR spin valve structure using heusler alloy
EP1107329B1 (en) Magnetic tunnel junction device, magnetic memory adopting the same, magnetic memory cell and access method of the same
US7382585B1 (en) Magnetic head having AMR reader, writer, and GMR reader
US7576948B2 (en) Magnetic field read sensor based on the extraordinary hall effect
KR19980081369A (ko) 박막 자기 헤드
US8574729B2 (en) Magnetic structure including two ferromagnetically coupled magnetic layers and method of manufacturing same
CN100367352C (zh) 磁阻磁头以及磁记录-复制装置
US6669787B2 (en) Method of manufacturing a spin valve structure
US6452762B1 (en) Magneto-resistive element and production method thereof, magneto-resistive head, and magnetic recording/reproducing apparatus
US6731478B2 (en) Magnetoresistive effect head
TW408317B (en) Multi-channel magnetic head wigh magnetoresistive elements
JP2000113427A (ja) 薄膜デバイス、薄膜磁気ヘッドおよび磁気抵抗効果素子並びにそれらの製造方法

Legal Events

Date Code Title Description
GD4A Issue of patent certificate for granted invention patent
MM4A Annulment or lapse of patent due to non-payment of fees