Magnetic tunnel junction device
    1.
    发明授权
    Magnetic tunnel junction device 有权
    磁隧道连接装置

    公开(公告)号:US08216703B2

    公开(公告)日:2012-07-10

    申请号:US12035011

    申请日:2008-02-21

    IPC分类号: G11B5/39

    摘要: A magnetic tunnel junction (MTJ) (10) employing a dielectric tunneling barrier (16), useful in magnetoresistive random access memories (MRAMs) and other devices, has a synthetic antiferromagnet (SAF) structure (14, 16), comprising two ferromagnetic (FM) layers (26, 41; 51, 58; 61, 68) separated by a coupling layer (38, 56, 66). Improved magnetoresistance (MR) ratio is obtained by providing a further layer (44, 46, 46′, 47, 52, 62), e.g. containing Ta, preferably spaced apart from the coupling layer (38, 56, 66) by a FM layer (41, 30-2, 54). The further layer (44, 46, 46′, 47, 52, 62) may be a Ta dusting layer (44) covered by a FM layer (30-2), or a Ta containing FM alloyed layer (46), or a stack (46′) of interleaved FM and N-FM layers, or other combination (47, 62). Furthering these benefits, another FM layer, e.g., CoFe, NiFe, (30, 30-1, 51, 61) is desirably provided between the further layer (44, 46, 46′, 47, 52, 62) and the tunneling barrier (16). Ta, Zr, Hf, Ti, Mg, Nb, V, Zn, Cr, NiFeX, CoFeX and CoFeBX (X═Ta, Zr, Hf, Ti, Mg, Nb, V, Zn, Cr) are useful for the further layer (44, 46, 46′, 47, 52, 62).

    摘要翻译: 采用磁阻随机存取存储器(MRAM)和其它器件的电介质隧道势垒(16)的磁性隧道结(MTJ)(10)具有合成的反铁磁(SAF)结构(14,16),包括两个铁磁( FM)层(26,41; 51,58; 61,68),由耦合层(38,56,66)分隔开。 通过提供另外的层(44,46,46',47,52,62),例如,可以获得改善的磁阻(MR)比。 含有Ta,优选地通过FM层(41,30-2,54)与耦合层(38,56,66)间隔开。 另外的层(44,46,46',47,52,62)可以是由FM层(30-2)或含Ta的FM合金层(46)覆盖的Ta粉化层(44),或 交错FM和N-FM层的叠层(46'),或其他组合(47,62)。 进一步提高这些益处,期望地在另一层(44,46,46',47,52,62)和隧道势垒之间提供另一个FM层,例如CoFe,NiFe(30,30-1,51,61) (16)。 Ta,Zr,Hf,Ti,Mg,Nb,V,Zn,Cr,NiFeX,CoFeX和CoFeBX(X = Ta,Zr,Hf,Ti,Mg,Nb,V,Zn,Cr) (44,46,46',47,52,62)。

    Magnetic tunnel junction device with improved barrier layer
    2.
    发明授权
    Magnetic tunnel junction device with improved barrier layer 有权
    具有改善阻挡层的磁隧道结器件

    公开(公告)号:US07635654B2

    公开(公告)日:2009-12-22

    申请号:US11341986

    申请日:2006-01-27

    IPC分类号: H01L21/316 H01L27/115

    CPC分类号: H01L43/08 H01L43/12

    摘要: Methods and apparatus are provided for magnetic tunnel junction (MTJ) devices and arrays, comprising metal-insulator-metal (M-I-M) structures with opposed first and second ferro-magnetic electrodes with alterable relative magnetization direction. The insulator is formed by depositing an oxidizable material (e.g., Al) on the first electrode, naturally oxidizing it, e.g., at about 0.03 to 10 milli-Torr for up to a few thousand seconds at temperatures below about 35° C., then further rapidly (e.g., plasma) oxidizing at a rate much larger than that of the initial natural oxidation. The second electrode of the M-I-M structure is formed on this oxide. More uniform tunneling properties result. A second oxidizable material layer is optionally provided after the initial natural oxidation and before the rapid oxidation step during which it is substantially entirely converted to insulating oxide. A second natural oxidation cycle may be optionally provided before the second layer is rapidly oxidized.

    摘要翻译: 提供了用于磁性隧道结(MTJ)器件和阵列的方法和装置,其包括金属 - 绝缘体 - 金属(M-I-M)结构,具有相对的具有可变相对磁化方向的第一和第二铁磁电极。 绝缘体通过在第一电极上沉积可氧化材料(例如,Al)而形成,其自然氧化,例如在低于约35℃的温度下在约0.03至10毫乇达数千秒,然后 进一步快速(例如,等离子体)以比初始自然氧化的速率更大的速率氧化。 在该氧化物上形成M-I-M结构的第二电极。 导致更均匀的隧道性质。 任选地,在初始自然氧化之后和快速氧化步骤之间提供第二可氧化材料层,在该氧化步骤期间,其基本上完全转化为绝缘氧化物。 可以任选地在第二层被快速氧化之前提供第二自然氧化循环。

    Magnetic tunnel junction structure and method
    3.
    发明授权
    Magnetic tunnel junction structure and method 失效
    磁隧道结结构及方法

    公开(公告)号:US07572645B2

    公开(公告)日:2009-08-11

    申请号:US11601129

    申请日:2006-11-15

    IPC分类号: H01L29/76

    摘要: Methods and apparatus are provided for magnetic tunnel junctions (MTJs) (10, 50) employing synthetic antiferromagnet (SAF) free layers (14, 14′). The MTJ (10, 50) comprises a pinned ferromagnetic (FM) layer (32, 18), the SAF (14) and a tunneling barrier (16) therebetween. The SAF (14) has a first higher spin polarization FM layer (30) proximate the tunneling barrier (16) and a second FM layer (26) desirably separated from the first FM layer (30) by a coupling layer (28), with magnetostriction adapted to compensate the magnetostriction of the first FM layer (30). Such compensation reduces the net magnetostriction of the SAF (14) to near zero even with high spin polarization proximate the tunneling barrier (16). Higher magnetoresistance ratios (MRs) are obtained without adverse affect on other MTJ (10, 50) properties. NiFe combinations are desirable for the first (30) and second (26) free FM layers, with more Fe in the first (30) free layer and less Fe in the second (26) free layer. CoFeB and NiFeCo are also useful in the free layers.

    摘要翻译: 提供了使用合成反铁磁(SAF)自由层(14,14')的磁隧道结(MTJ)(10,50)的方法和装置。 MTJ(10,50)包括钉扎铁磁(FM)层(32,18),SAF(14)和它们之间的隧道势垒(16)。 SAF(14)具有靠近隧道势垒(16)的第一高自旋极化FM层(30)和期望地通过耦合层(28)从第一FM层(30)分离的第二FM层(26),其中, 磁致伸缩适于补偿第一FM层(30)的磁致伸缩。 即使在靠近隧道势垒(16)的高自旋极化下,这种补偿也将SAF(14)的净磁致伸缩降低到接近于零。 获得更高的磁阻比(MRs),而不影响其他MTJ(10,50)性能。 对于第一(30)和第二(26)自由的FM层,NiFe组合是理想的,在第一(30)自由层中具有更多的Fe,在第二(26)自由层中具有更少的Fe。 CoFeB和NiFeCo也可用于自由层。

    Low power magnetoresistive random access memory elements

    公开(公告)号:US07329935B2

    公开(公告)日:2008-02-12

    申请号:US11581951

    申请日:2006-10-16

    IPC分类号: H01L29/82 H01L43/00

    摘要: Low power magnetoresistive random access memory elements and methods for fabricating the same are provided. In one embodiment, a magnetoresistive random access device has an array of memory elements. Each element comprises a fixed magnetic portion, a tunnel barrier portion, and a free SAF structure. The array has a finite magnetic field programming window Hwin represented by the equation Hwin≈(Hsat−σsat)−(Hsw+σsw), where Hsw is a mean switching field for the array, Hsat is a mean saturation field for the array, and Hsw for each memory element is represented by the equation HSW≅√{square root over (HkHSAT)}, where Hk represents a total anisotropy and HSAT represents an anti-ferromagnetic coupling saturation field for the free SAF structure of each memory element. N is an integer greater than or equal to 1. Hk, HSAT, and N for each memory element are selected such that the array requires current to operate that is below a predetermined current value.

    Synthetic antiferromagnet structures for use in MTJs in MRAM technology
    5.
    发明授权
    Synthetic antiferromagnet structures for use in MTJs in MRAM technology 失效
    在MRAM技术中用于MTJ的合成反铁磁体结构

    公开(公告)号:US07226796B2

    公开(公告)日:2007-06-05

    申请号:US11182149

    申请日:2005-07-15

    IPC分类号: H01L21/00 H01L29/76

    摘要: A magnetic tunnel junction (MTJ), which is useful in magnetoresistive random access memories (MRAMs), has a free layer which is a synthetic antiferromagnet (SAF) structure. This SAF is composed of two ferromagnetic layers that are separated by a coupling layer. The coupling layer has a base material that is non-magnetic and also other materials that improve thermal endurance, control of the coupling strength of the SAF, and magnetoresistance ratio (MR). The preferred base material is ruthenium and the preferred other material is tantalum. Furthering these benefits, cobalt-iron is added at the interface between the tantalum and one of the ferromagnetic layers. Also the coupling layer can have even more layers and the materials used can vary. Also the coupling layer itself can be an alloy.

    摘要翻译: 在磁阻随机存取存储器(MRAM)中有用的磁隧道结(MTJ)具有作为合成反铁磁体(SAF)结构的自由层。 该SAF由被耦合层隔开的两个铁磁层组成。 耦合层具有非磁性的基体材料以及改善耐热性,SAF的耦合强度的控制和磁阻比(MR)的其它材料。 优选的基材是钌,优选的其它材料是钽。 进一步提高这些优点,在​​钽和铁磁层之一的界面处加入钴铁。 此外,耦合层可以具有甚至更多的层,并且所使用的材料可以变化。 耦合层本身也可以是合金。

    Synthetic antiferromagnet structures for use in MTJs in MRAM technology
    6.
    发明授权
    Synthetic antiferromagnet structures for use in MTJs in MRAM technology 有权
    在MRAM技术中用于MTJ的合成反铁磁体结构

    公开(公告)号:US06946697B2

    公开(公告)日:2005-09-20

    申请号:US10740338

    申请日:2003-12-18

    摘要: A magnetic tunnel junction (MTJ), which is useful in magnetoresistive random access memories (MRAMs), has a free layer which is a synthetic antiferromagnet (SAF) structure. This SAF is composed of two ferromagnetic layers that are separated by a coupling layer. The coupling layer has a base material that is non-magnetic and also other materials that improve thermal endurance, control of the coupling strength of the SAF, and magnetoresistance ratio (MR). The preferred base material is ruthenium and the preferred other material is tantalum. Furthering these benefits, cobalt-iron is added at the interface between the tantalum and one of the ferromagnetic layers. Also the coupling layer can have even more layers and the materials used can vary. Also the coupling layer itself can be an alloy.

    摘要翻译: 在磁阻随机存取存储器(MRAM)中有用的磁隧道结(MTJ)具有作为合成反铁磁体(SAF)结构的自由层。 该SAF由两个被耦合层隔开的铁磁层组成。 耦合层具有非磁性的基体材料以及改善耐热性,SAF的耦合强度的控制和磁阻比(MR)的其它材料。 优选的基材是钌,优选的其它材料是钽。 进一步提高这些优点,在​​钽和铁磁层之一的界面处加入钴铁。 此外,耦合层可以具有甚至更多的层,并且所使用的材料可以变化。 耦合层本身也可以是合金。

    METHODS AND STRUCTURES FOR EXCHANGE-COUPLED MAGNETIC MULTI-LAYER STRUCTURE WITH IMPROVED OPERATING TEMPERATURE BEHAVIOR
    10.
    发明申请
    METHODS AND STRUCTURES FOR EXCHANGE-COUPLED MAGNETIC MULTI-LAYER STRUCTURE WITH IMPROVED OPERATING TEMPERATURE BEHAVIOR 审中-公开
    交替耦合磁性多层结构与改进工作温度行为的方法与结构

    公开(公告)号:US20090121266A1

    公开(公告)日:2009-05-14

    申请号:US11938816

    申请日:2007-11-13

    IPC分类号: H01L27/108 H01L21/02

    摘要: Exchange-coupled magnetic multilayer structures for use with toggle MRAM devices and the like include a tunnel barrier layer (108) and a synthetic antiferromagnet (SAF) structure (300) formed on the tunnel barrier layer (108), wherein the SAF (300) includes a plurality (e.g., four or more) of ferromagnetic layers (302, 306, 310, 314) antiferromagnetically or ferromagnetically coupled by a plurality of respective coupling layers (304, 308, 312). The microcrystalline texture of one or more of the ferromagnetic layers is reduced to substantially zero as measured from X-Ray Diffraction by exposure of various layers to oxygen, by forming a detexturing layer, by adding oxygen during the ferromagnetic or coupling layer fabrication, and/or by using amorphous materials.

    摘要翻译: 用于切换MRAM器件等的交换耦合磁性多层结构包括形成在隧道势垒层(108)上的隧道势垒层(108)和合成反铁磁体(SAF)结构(300),其中SAF(300) 包括由多个相应的耦合层(304,308,312)反铁磁或铁磁耦合的多个(例如,四个或更多个)铁磁层(302,306,310,314)。 一个或多个铁磁性层的微晶结构由X射线衍射测得的,通过各种氧气暴露于氧,通过在铁磁或耦合层制造过程中加入氧来形成去附着层,和/ 或通过使用无定形材料。