公开(公告)号：US07528457B2

公开(公告)日：2009-05-05

申请号：US11404446

申请日：2006-04-14

申请人： Cheng T. Horng ,  Hui-Chuan Wang ,  Min Li ,  Ru-Ying Tong ,  Tong Zhao ,  Yimin Guo

发明人： Cheng T. Horng ,  Hui-Chuan Wang ,  Min Li ,  Ru-Ying Tong ,  Tong Zhao ,  Yimin Guo

IPC分类号： H01L29/82 ,  G11C11/02

CPC分类号： H01L43/10 ,  H01L43/08 ,  H01L43/12

摘要： An MTJ in an MRAM array or TMR read head is disclosed in which a capping layer has a bilayer configuration with a non-magnetic NiFeX inner layer on a NiFe free layer and a Ta layer on the NiFeX layer to improve dR/R and minimize magnetostriction. Optionally, a trilayer configuration may be employed where the Ta layer is sandwiched between an inner NiFeX layer and an outer Ru layer. The X component in NiFeX is preferably an element having an oxidation potential greater than Ni or Fe such as Mg, Hf, Zr, Nb, or Ta. NiFeX is preferably formed by co-sputtering a NiFe target with an X target at a forward power of about 200 W and 50 W, respectively. In an MRAM structure, the Mg content in NiFeMg may be increased to >50 atomic % to improve the gettering power of removing oxygen from the free layer.

摘要翻译： 公开了一种MRAM阵列或TMR读取头中的MTJ，其中封盖层具有在NiFe自由层上的非磁性NiFeX内层和NiFeX层上的Ta层的双层结构，以改善dR / R并最小化磁致伸缩 。 任选地，可以采用三层结构，其中Ta层夹在内部NiFeX层和外部Ru层之间。 NiFeX中的X成分优选为具有大于Ni，Fe的氧化电位的元素，例如Mg，Hf，Zr，Nb或Ta。 优选通过以约200W和50W的正向功率共同溅射具有X靶的NiFe靶来形成NiFeX。 在MRAM结构中，NiFeMg中的Mg含量可以增加到> 50原子％以提高从自由层除去氧的吸气能力。

公开(公告)号：US20070243638A1

公开(公告)日：2007-10-18

申请号：US11404446

申请日：2006-04-14

申请人： Cheng Horng ,  Hui-Chuan Wang ,  Min Li ,  Ru-Ying Tong ,  Tong Zhao ,  Yimin Guo

发明人： Cheng Horng ,  Hui-Chuan Wang ,  Min Li ,  Ru-Ying Tong ,  Tong Zhao ,  Yimin Guo

IPC分类号： H01L21/00

CPC分类号： H01L43/10 ,  H01L43/08 ,  H01L43/12

摘要： An MTJ in an MRAM array or TMR read head is disclosed in which a capping layer has a bilayer configuration with a non-magnetic NiFeX inner layer on a NiFe free layer and a Ta layer on the NiFeX layer to improve dR/R and minimize magnetostriction. Optionally, a trilayer configuration may be employed where the Ta layer is sandwiched between an inner NiFeX layer and an outer Ru layer. The X component in NiFeX is preferably an element having an oxidation potential greater than Ni or Fe such as Mg, Hf, Zr, Nb, or Ta. NiFeX is preferably formed by co-sputtering a NiFe target with an X target at a forward power of about 200 W and 50 W, respectively. In an MRAM structure, the Mg content in NiFeMg may be increased to >50 atomic % to improve the gettering power of removing oxygen from the free layer.

摘要翻译： 公开了一种MRAM阵列或TMR读取头中的MTJ，其中封盖层具有在NiFe自由层上的非磁性NiFeX内层和NiFeX层上的Ta层的双层结构，以改善dR / R并最小化磁致伸缩 。 任选地，可以采用三层结构，其中Ta层夹在内部NiFeX层和外部Ru层之间。 NiFeX中的X成分优选为具有大于Ni，Fe的氧化电位的元素，例如Mg，Hf，Zr，Nb或Ta。 优选通过以约200W和50W的正向功率共同溅射具有X靶的NiFe靶来形成NiFeX。 在MRAM结构中，NiFeMg中的Mg含量可以增加到> 50原子％以提高从自由层除去氧的吸气能力。

公开(公告)号：US20080225583A1

公开(公告)日：2008-09-18

申请号：US11717347

申请日：2007-03-13

申请人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

发明人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

IPC分类号： G11C11/15 ,  H01L21/00

CPC分类号： G11C11/16 ,  Y10S977/935

摘要： We describe a CPP MTJ MRAM element that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes a tunneling barrier layer of MgO and a non-magnetic CPP layer of Cu or Cr and utilizes a novel free layer comprising a thin layer of Ta or Hf sandwiched by layers of CoFeB. The device is characterized by values of DR/R between approximately 95% and 105%.

摘要翻译： 我们描述了利用自旋角动量转移作为改变自由层的磁矩方向的机制的CPP MTJ MRAM元件。 该器件包括MgO的隧道势垒层和Cu或Cr的非磁性CPP层，并且利用包含被CoFeB层夹在中间的Ta或Hf薄层的新型自由层。 该装置的特征在于DR / R的值在大约95％和105％之间。

公开(公告)号：US20100178715A1

公开(公告)日：2010-07-15

申请号：US12661365

申请日：2010-03-16

申请人： Po-Kang Wang ,  Yimin Guo ,  Cheng T. Horng ,  Tai Min ,  Ru-Ying Tong

发明人： Po-Kang Wang ,  Yimin Guo ,  Cheng T. Horng ,  Tai Min ,  Ru-Ying Tong

IPC分类号： H01L21/336 ,  H01L21/8246

CPC分类号： H01L43/08

摘要： An MRAM is disclosed that has a MTJ comprised of a ferromagnetic layer with a magnetization direction along a first axis, a super-paramagnetic (SP) free layer, and an insulating layer formed therebetween. The SP free layer has a remnant magnetization that is substantially zero in the absence of an external field, and in which magnetization is roughly proportional to an external field until reaching a saturation value. In one embodiment, a separate storage layer is formed above, below, or adjacent to the MTJ and has uniaxial anisotropy with a magnetization direction along its easy axis which parallels the first axis. In a second embodiment, the storage layer is formed on a non-magnetic conducting spacer layer within the MTJ and is patterned simultaneously with the MTJ. The SP free layer may be multiple layers or laminated layers of CoFeB. The storage layer may have a SyAP configuration and a laminated structure.

公开(公告)号：US20090256220A1

公开(公告)日：2009-10-15

申请号：US12082155

申请日：2008-04-09

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Yimin Guo

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Yimin Guo

IPC分类号： H01L29/82 ,  H01L21/00

CPC分类号： H01L43/08 ,  H01L43/12 ,  Y10S977/883

摘要： A STT-RAM MTJ that minimizes spin-transfer magnetization switching current (Jc) while achieving a high dR/R is disclosed. The MTJ has a MgO tunnel barrier formed by natural oxidation to achieve a low RA, and a CoFeB/FeSiO/CoFeB composite free layer with a middle nanocurrent channel layer to minimize Jc0. There is a thin Ru capping layer for a spin scattering effect. The reference layer has a shape anisotropy and Hc substantially greater than that of the free layer to establish a “self-pinned” state. The free layer, capping layer and hard mask are formed in an upper section of a nanopillar that has an area substantially less than a lower pedestal section which includes a bottom electrode, reference layer, seed layer, and tunnel barrier layer. The reference layer is comprised of an enhanced damping constant material that may be an insertion layer, and the free layer has a low damping constant.

摘要翻译： 公开了一种在实现高dR / R的同时使自旋转移磁化开关电流（Jc）最小化的STT-RAM MTJ。 MTJ具有通过自然氧化形成的MgO隧道势垒以实现低RA，以及具有中间纳米通道层的CoFeB / FeSiO / CoFeB复合自由层以使Jc0最小化。 有一个薄的Ru覆盖层用于自旋散射效应。 参考层具有形状各向异性，并且Hc基本上大于自由层的Hc以形成“自固定”状态。 自由层，覆盖层和硬掩模形成在纳米柱的上部，其具有基本上小于包括底部电极，参考层，种子层和隧道势垒层的下基座部分的面积。 参考层由增强的阻尼常数材料组成，其可以是插入层，并且自由层具有低阻尼常数。

公开(公告)号：US07480173B2

公开(公告)日：2009-01-20

申请号：US11717347

申请日：2007-03-13

申请人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

发明人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

IPC分类号： G11C11/00

CPC分类号： G11C11/16 ,  Y10S977/935

摘要： A CPP MTJ MRAM element utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes a tunneling barrier layer of MgO and a non-magnetic CPP layer of Cu or Cr and utilizes a novel free layer comprising a thin layer of Ta or Hf sandwiched by layers of CoFeB. The device is characterized by values of DR/R between approximately 95% and 105%.

摘要翻译： CPP MTJ MRAM元件利用自旋角动量的传递作为改变自由层的磁矩方向的机构。 该器件包括MgO的隧道势垒层和Cu或Cr的非磁性CPP层，并且利用包含被CoFeB层夹在中间的Ta或Hf薄层的新型自由层。 该装置的特征在于DR / R的值在大约95％和105％之间。

公开(公告)号：US20080239589A1

公开(公告)日：2008-10-02

申请号：US11728491

申请日：2007-03-26

申请人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

发明人： Yimin Guo ,  Cheng T. Horng ,  Ru-Ying Tong

IPC分类号： G11B5/39

CPC分类号： G01R33/093 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3254 ,  H01F10/3272 ,  H01F41/302

摘要： We describe a CPP MTJ MRAM element that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes a tunneling barrier layer of MgO and a non-magnetic CPP layer of Cu or Cr and utilizes a novel synthetic free layer having three ferromagnetic layers mutually exchange coupled in pairwise configurations. The free layer comprises an inner ferromagnetic and two outer ferromagnetic layers, with the inner layer being ferromagnetically exchange coupled to one outer layer and anti-ferromagnetically exchange coupled to the other outer layer. The ferromagnetic coupling is very strong across an ultra-thin layer of Ta, Hf or Zr of thickness preferably less than 0.4 nm.

摘要翻译： 我们描述了利用自旋角动量转移作为改变自由层的磁矩方向的机制的CPP MTJ MRAM元件。 该器件包括MgO的隧道势垒层和Cu或Cr的非磁性CPP层，并且利用具有三个铁磁层的新型合成自由层，其在成对配置中相互交换耦合。 自由层包括内部铁磁体和两个外部铁磁性层，其中内层被铁磁交换耦合到一个外层并与另一个外层反耦合地进行反铁磁交换。 在厚度优选小于0.4nm的Ta，Hf或Zr的超薄层上，铁磁耦合是非常强的。

公开(公告)号：US07948044B2

公开(公告)日：2011-05-24

申请号：US12082155

申请日：2008-04-09

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Yimin Guo

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Yimin Guo

IPC分类号： H01L29/82

CPC分类号： H01L43/08 ,  H01L43/12 ,  Y10S977/883

摘要： A STT-RAM MTJ that minimizes spin-transfer magnetization switching current (Jc) while achieving a high dR/R is disclosed. The MTJ has a MgO tunnel barrier formed by natural oxidation to achieve a low RA, and a CoFeB/FeSiO/CoFeB composite free layer with a middle nanocurrent channel layer to minimize Jc0. There is a thin Ru capping layer for a spin scattering effect. The reference layer has a shape anisotropy and Hc substantially greater than that of the free layer to establish a “self-pinned” state. The free layer, capping layer and hard mask are formed in an upper section of a nanopillar that has an area substantially less than a lower pedestal section which includes a bottom electrode, reference layer, seed layer, and tunnel barrier layer. The reference layer is comprised of an enhanced damping constant material that may be an insertion layer, and the free layer has a low damping constant.

摘要翻译： 公开了一种在实现高dR / R的同时使自旋转移磁化开关电流（Jc）最小化的STT-RAM MTJ。 MTJ具有通过自然氧化形成的MgO隧道势垒以实现低RA，以及具有中间纳米通道层的CoFeB / FeSiO / CoFeB复合自由层以使Jc0最小化。 有一个薄的Ru覆盖层用于自旋散射效应。 参考层具有形状各向异性，并且Hc基本上大于自由层的Hc以形成“自固定”状态。 自由层，覆盖层和硬掩模形成在纳米柱的上部，其具有基本上小于包括底部电极，参考层，种子层和隧道势垒层的下基座部分的面积。 参考层由增强的阻尼常数材料组成，其可以是插入层，并且自由层具有低阻尼常数。

公开(公告)号：US20100176429A1

公开(公告)日：2010-07-15

申请号：US12661345

申请日：2010-03-16

申请人： Po-Kang Wang ,  Yimin Guo ,  Cheng T. Horng ,  Tai Min ,  Ru-Ying Tong

发明人： Po-Kang Wang ,  Yimin Guo ,  Cheng T. Horng ,  Tai Min ,  Ru-Ying Tong

IPC分类号： H01L29/94

CPC分类号： H01L43/08

摘要： An MRAM is disclosed that has a MTJ comprised of a ferromagnetic layer with a magnetization direction along a first axis, a super-paramagnetic (SP) free layer, and an insulating layer formed therebetween. The SP free layer has a remnant magnetization that is substantially zero in the absence of an external field, and in which magnetization is roughly proportional to an external field until reaching a saturation value. In one embodiment, a separate storage layer is formed above, below, or adjacent to the MTJ and has uniaxial anisotropy with a magnetization direction along its easy axis which parallels the first axis. In a second embodiment, the storage layer is formed on a non-magnetic conducting spacer layer within the MTJ and is patterned simultaneously with the MTJ. The SP free layer may be multiple layers or laminated layers of CoFeB. The storage layer may have a SyAP configuration and a laminated structure.

摘要翻译： 公开了一种MRAM，其具有由沿第一轴的磁化方向的铁磁层，超顺磁性（SP）自由层和在它们之间形成的绝缘层构成的MTJ。 SP自由层具有在没有外部场的情况下基本为零的残余磁化，并且其中磁化大致与外部场成正比，直到达到饱和值。 在一个实施例中，单独的存储层形成在MTJ的上方，下方或附近，并且具有沿其易于轴线平行于第一轴线的磁化方向的单轴各向异性。 在第二实施例中，存储层形成在MTJ内的非磁性导电间隔层上，并与MTJ同时构图。 SP自由层可以是CoFeB的多层或层压层。 存储层可以具有SyAP配置和层压结构。

公开(公告)号：US20120064640A1

公开(公告)日：2012-03-15

申请号：US13373173

申请日：2011-11-07

申请人： Yimin Guo ,  Cheng Horng ,  Ru-Ying Tong

发明人： Yimin Guo ,  Cheng Horng ,  Ru-Ying Tong

IPC分类号： H01L43/12

CPC分类号： G01R33/093 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3254 ,  H01F10/3272 ,  H01F41/302

摘要： A method of forming a CPP MTJ MRAM element that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes a tunneling barrier layer of MgO and a non-magnetic CPP layer of Cu or Cr and utilizes a novel synthetic free layer having three ferromagnetic layers mutually exchange coupled in pairwise configurations. The free layer comprises an inner ferromagnetic and two outer ferromagnetic layers, with the inner layer being ferromagnetically exchange coupled to one outer layer and anti-ferromagnetically exchange coupled to the other outer layer. The ferromagnetic coupling is very strong across an ultra-thin layer of Ta, Hf or Zr of thickness preferably less than 0.4 nm.