公开(公告)号：US20090027810A1

公开(公告)日：2009-01-29

申请号：US11880583

申请日：2007-07-23

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

IPC分类号： G11B5/33 ,  G11B5/127

CPC分类号： H01L43/08 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3272 ,  H01F10/329 ,  H01F10/3295 ,  H01F41/307 ,  H01L43/10 ,  H01L43/12

摘要： We describe the structure and method of forming a STT-MTJ MRAM cell that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes an IrMn pinning layer, a SyAP pinned layer, a naturally oxidized, crystalline MgO tunneling barrier layer that is formed on an Ar-ion plasma smoothed surface of the pinned layer and, in one embodiment, a free layer that comprises an amorphous layer of Co60Fe20B20. of approximately 20 angstroms thickness formed between two crystalline layers of Fe of 3 and 6 angstroms thickness respectively. The free layer is characterized by a low Gilbert damping factor and by very strong polarizing action on conduction electrons. The resulting cell has a low critical current, a high dR/R and a plurality of such cells will exhibit a low variation of both resistance and pinned layer magnetization angular dispersion.

摘要翻译： 我们描述形成使用自旋角动量转移的STT-MTJ MRAM单元的结构和方法，作为改变自由层的磁矩方向的机制。 该器件包括形成在被钉扎层的Ar离子等离子体平滑表面上的IrMn钉扎层，SyAP钉扎层，自然氧化的结晶的MgO隧道势垒层，在一个实施例中，包含非晶态的自由层 Co60Fe20B20层。 分别在3和6埃的Fe的两个结晶层之间形成约20埃的厚度。 自由层的特征在于低吉尔伯特阻尼因子和对传导电子的非常强的偏振作用。 所得到的电池具有低临界电流，高dR / R，并且多个这样的电池将呈现电阻和钉扎层磁化角分散的低变化。

公开(公告)号：US08436437B2

公开(公告)日：2013-05-07

申请号：US12803191

申请日：2010-06-21

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

IPC分类号： H01L29/82

CPC分类号： H01L43/08 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3272 ,  H01F10/329 ,  H01F10/3295 ,  H01F41/307 ,  H01L43/10 ,  H01L43/12

摘要： A STT-MTJ MRAM cell that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer includes an IrMn pinning layer, a SyAP pinned layer, a naturally oxidized, crystalline MgO tunneling barrier layer that is formed on an Ar-ion plasma smoothed surface of the pinned layer and a free layer that comprises an amorphous layer of Co60Fe20B20 of approximately 20 angstroms thickness or an amorphous ferromagnetic layer of Co40Fe40B20 of approximately 15 angstroms thickness formed between two crystalline layers of Fe of 3 and 6 angstroms thickness respectively. The free layer is characterized by a low Gilbert damping factor and by very strong polarizing action on conduction electrons. The resulting cell has a low critical current, a high dR/R and a plurality of such cells will exhibit a low variation of both resistance and pinned layer magnetization angular dispersion.

摘要翻译： 利用自旋角度动量的转移作为改变自由层的磁矩方向的机构的STT-MTJ MRAM单元包括IrMn钉扎层，SyAP钉扎层，自然氧化的结晶的MgO隧穿势垒层，其形成于 被钉扎层的Ar离子等离子体平滑表面和包含大约20埃厚度的Co60Fe20B20的非晶层的自由层或者在3和6的Fe的两个结晶层之间形成约15埃厚度的Co40Fe40B20的非晶铁磁层 埃厚度。 自由层的特征在于低吉尔伯特阻尼因子和对传导电子的非常强的偏振作用。 所得到的电池具有低临界电流，高dR / R，并且多个这样的电池将呈现电阻和钉扎层磁化角分散的低变化。

公开(公告)号：US08138561B2

公开(公告)日：2012-03-20

申请号：US12284066

申请日：2008-09-18

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Po-Kang Wang ,  Robert Beach ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Po-Kang Wang ,  Robert Beach ,  Witold Kula

IPC分类号： H01L29/82

CPC分类号： H01L43/08 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  G11C11/1675 ,  H01F10/3254 ,  H01F10/3259 ,  H01F10/3272 ,  H01F41/307 ,  H01L43/12

摘要： A STT-RAM MTJ is disclosed with a MgO tunnel barrier formed by a NOX process, a CoFeB/FeSiO/CoFeB composite free layer with a middle nanocurrent channel layer to minimize Jc0, and a Ru capping layer to enhance the spin scattering effect and increase dR/R. Good write margin is achieved by modifying the NOX process to afford a RA less than 10 ohm-μm2 and good read margin is realized with a dR/R of >100% by annealing at 330° C. or higher to form crystalline CoFeB free layers. The NCC thickness is maintained in the 6 to 10 Angstrom range to reduce Rp and avoid Fe(Si) granules from not having sufficient diameter to bridge the distance between upper and lower CoFeB layers. A FeSiO layer may be inserted below the Ru layer in the capping layer to prevent the Ru from causing a high damping constant in the upper CoFeB free layer.

摘要翻译： 公开了一种STT-RAM MTJ，其具有通过NOX工艺形成的MgO隧道势垒，具有中间纳米通道层的CoFeB / FeSiO / CoFeB复合自由层以最小化Jc0，以及Ru覆盖层以增强自旋散射效应并增加 dR / R。 通过改变NOX工艺以获得RA小于10欧姆 - μm2的良好的写入余量，并且通过在330℃或更高温度退火以dO / R> 100％实现良好的读取余量以形成结晶CoFeB自由层 。 NCC厚度保持在6至10埃范围内以减少Rp，并避免Fe（Si）颗粒不具有足够的直径以桥接上部和下部CoFeB层之间的距离。 可以在覆盖层中的Ru层下方插入FeSiO层，以防止Ru在上部CoFeB自由层中引起高阻尼常数。

公开(公告)号：US08080432B2

公开(公告)日：2011-12-20

申请号：US12803190

申请日：2010-06-21

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

IPC分类号： H01L21/00 ,  H01L21/336 ,  H01L21/461

CPC分类号： H01L43/08 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3272 ,  H01F10/329 ,  H01F10/3295 ,  H01F41/307 ,  H01L43/10 ,  H01L43/12

摘要： A method of forming a STT-MTJ MRAM cell that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes an IrMn pinning layer, a SyAP pinned layer, a naturally oxidized, crystalline MgO tunneling barrier layer that is formed on an Ar-ion plasma smoothed surface of the pinned layer and, in one embodiment, a free layer that comprises an amorphous layer of Co60Fe20B20. of approximately 20 angstroms thickness formed between two crystalline layers of Fe of 3 and 6 angstroms thickness respectively. The free layer is characterized by a low Gilbert damping factor and by very strong polarizing action on conduction electrons. The resulting cell has a low critical current, a high dR/R and a plurality of such cells will exhibit a low variation of both resistance and pinned layer magnetization angular dispersion.

摘要翻译： 形成利用自旋角动量转移的STT-MTJ MRAM单元的形成方法，作为改变自由层的磁矩方向的机构。 该器件包括形成在被钉扎层的Ar离子等离子体平滑表面上的IrMn钉扎层，SyAP钉扎层，自然氧化的结晶的MgO隧道势垒层，在一个实施例中，包含非晶态的自由层 Co60Fe20B20层。 分别在3和6埃的Fe的两个结晶层之间形成约20埃的厚度。 自由层的特征在于低吉尔伯特阻尼因子和对传导电子的非常强的偏振作用。 所得到的电池具有低临界电流，高dR / R，并且多个这样的电池将呈现电阻和钉扎层磁化角分散的低变化。

公开(公告)号：US20100261295A1

公开(公告)日：2010-10-14

申请号：US12803190

申请日：2010-06-21

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

IPC分类号： H01L21/8246

CPC分类号： H01L43/08 ,  B82Y25/00 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/3272 ,  H01F10/329 ,  H01F10/3295 ,  H01F41/307 ,  H01L43/10 ,  H01L43/12

摘要： A method of forming a STT-MTJ MRAM cell that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The device includes an IrMn pinning layer, a SyAP pinned layer, a naturally oxidized, crystalline MgO tunneling barrier layer that is formed on an Ar-ion plasma smoothed surface of the pinned layer and, in one embodiment, a free layer that comprises an amorphous layer of Co60Fe20B20.of approximately 20 angstroms thickness formed between two crystalline layers of Fe of 3 and 6 angstroms thickness respectively. The free layer is characterized by a low Gilbert damping factor and by very strong polarizing action on conduction electrons. The resulting cell has a low critical current, a high dR/R and a plurality of such cells will exhibit a low variation of both resistance and pinned layer magnetization angular dispersion.

摘要翻译： 形成利用自旋角动量转移的STT-MTJ MRAM单元的形成方法，作为改变自由层的磁矩方向的机构。 该器件包括形成在被钉扎层的Ar离子等离子体平滑表面上的IrMn钉扎层，SyAP钉扎层，自然氧化的结晶的MgO隧道势垒层，在一个实施例中，包含非晶态的自由层 分别在3和6埃厚度的Fe的两个结晶层之间形成大约20埃厚度的Co60Fe20B20的层。 自由层的特征在于低吉尔伯特阻尼因子和对传导电子的非常强的偏振作用。 所得到的电池具有低临界电流，高dR / R，并且多个这样的电池将呈现电阻和钉扎层磁化角分散的低变化。

公开(公告)号：US20100240151A1

公开(公告)日：2010-09-23

申请号：US12383298

申请日：2009-03-23

申请人： Rodolfo Belen ,  Tom Zhong ,  Witold Kula ,  Chyu-Jiuh Torng

发明人： Rodolfo Belen ,  Tom Zhong ,  Witold Kula ,  Chyu-Jiuh Torng

IPC分类号： H01L21/04

CPC分类号： H01L27/228 ,  H01L43/12

摘要： A method for forming a MTJ in a STT-MRAM is disclosed in which the easy-axis CD is determined independently of the hard-axis CD. One approach involves two photolithography steps each followed by two plasma etch steps to form a post in a hard mask which is transferred through a MTJ stack of layers. The hard mask has an upper Ta layer with a thickness of 300 to 400 Angstroms and a lower NiCr layer less than 50 Angstroms thick. The upper Ta layer is etched with a fluorocarbon etch while lower NiCr layer and underlying MTJ layers are etched with a CH3OH. Preferably, a photoresist mask layer is removed by oxygen plasma between the fluorocarbon and CH3OH plasma etches. A lower hard mask layer made of NiCr or the like is inserted to prevent formation and buildup of Ta etch residues that can cause device shunting.

摘要翻译： 公开了一种用于在STT-MRAM中形成MTJ的方法，其中容易轴CD独立于硬轴CD来确定。 一种方法涉及两个光刻步骤，每个步骤分别采用两个等离子体蚀刻步骤，以在通过MTJ堆叠层传送的硬掩模中形成柱。 硬掩模具有厚度为300至400埃的上层Ta层和小于50埃厚的较低NiCr层。 用氟碳蚀刻蚀刻上层Ta层，同时用CH3OH蚀刻下层NiCr层和下层MTJ层。 优选地，在碳氟化合物和CH 3 OH等离子蚀刻之间的氧等离子体去除光致抗蚀剂掩模层。 插入由NiCr等制成的下部硬掩模层以防止可能导致器件分流的Ta蚀刻残留物的形成和积累。

公开(公告)号：US07672093B2

公开(公告)日：2010-03-02

申请号：US11582244

申请日：2006-10-17

申请人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

发明人： Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jiuh Torng ,  Witold Kula

IPC分类号： G11B5/39 ,  G11B5/127

CPC分类号： H01F10/3254 ,  B82Y25/00 ,  G11B5/3163 ,  G11B5/3906 ,  G11C11/161 ,  H01F10/3281 ,  H01F10/3295 ,  H01F41/325 ,  H01L43/08 ,  H01L43/10 ,  H01L43/12 ,  Y10T29/49041 ,  Y10T29/49043 ,  Y10T29/49044 ,  Y10T29/49046 ,  Y10T29/49048 ,  Y10T29/49052

摘要： A high performance MTJ, and a process for manufacturing it, are described. A capping layer of NiFeHf is used to getter oxygen out of the free layer, thereby increasing the sharpness of the free layer-tunneling layer interface. The free layer comprises two NiFe layers whose magnetostriction constants are of opposite sign, thereby largely canceling one another.

摘要翻译： 描述了高性能MTJ及其制造方法。 使用NiFeHf的覆盖层将氧气从自由层中吸出，从而增加了自由层 - 隧道层界面的清晰度。 自由层包含两个NiFe层，它们的磁致伸缩常数是相反的，从而很大程度地相互抵消。

公开(公告)号：US08183061B2

公开(公告)日：2012-05-22

申请号：US12931648

申请日：2011-02-07

申请人： Tom Zhong ,  Chyu-Jiuh Torng ,  Rongfu Xiao ,  Adam Zhong ,  Wai-Ming Johnson Kan ,  Daniel Liu

发明人： Tom Zhong ,  Chyu-Jiuh Torng ,  Rongfu Xiao ,  Adam Zhong ,  Wai-Ming Johnson Kan ,  Daniel Liu

IPC分类号： H01L21/441

CPC分类号： H01L27/228 ,  H01L43/12

摘要： A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.

摘要翻译： 公开了一种STT-MRAM集成方案，其中通过在CMOS着陆焊盘，接触和覆盖VAC的金属（VAM）焊盘上形成中间通孔接触（VAC）来简化MTJ和CMOS金属之间的连接，以及MTJ 在VAM上。 执行双镶嵌工艺，通过设备区域中的VAC / VAM / MTJ堆叠将BIT线金属连接到CMOS着陆焊盘，并通过设备区域外的BIT连接通孔将BIT线连接焊盘连接到CMOS连接焊盘。 VAM焊盘是由Ta，TaN或用作扩散阻挡层的其它导体制成的单层或复合材料，具有用于MTJ形成的高度光滑的表面，并且在化学机械抛光工艺期间提供了与补充介电材料的优异选择性。 每个VAC为500至3000埃厚，以最小化额外的电路电阻并最小化蚀刻负担。

公开(公告)号：US08133745B2

公开(公告)日：2012-03-13

申请号：US11975045

申请日：2007-10-17

申请人： Tom Zhong ,  Rongfu Xiao ,  Chyu-Jiuh Torng ,  Adam Zhong

发明人： Tom Zhong ,  Rongfu Xiao ,  Chyu-Jiuh Torng ,  Adam Zhong

IPC分类号： H01L21/00

CPC分类号： H01L43/12 ,  B82Y10/00 ,  H01L27/228

摘要： A method for forming a MTJ in a STT-MRAM is disclosed in which the easy-axis CD is determined independently of the hard-axis CD. One approach involves two photolithography steps and two etch steps to form a post in a hard mask which is transferred through a MTJ stack of layers by a third etch process. Optionally, the third etch may stop on the tunnel barrier or in the free layer. A second embodiment involves forming a first parallel line pattern on a hard mask layer and transferring the line pattern through the MTJ stack with a first etch step. A planar insulation layer is formed adjacent to the sidewalls in the line pattern and then a second parallel line pattern is formed which is transferred by a second etch through the MTJ stack to form a post pattern. Etch end point may be controlled independently for hard-axis and easy-axis dimensions.

摘要翻译： 公开了一种用于在STT-MRAM中形成MTJ的方法，其中容易轴CD独立于硬轴CD来确定。 一种方法涉及两个光刻步骤和两个蚀刻步骤，以在通过第三蚀刻工艺通过MTJ叠层堆叠的硬掩模中形成柱。 可选地，第三蚀刻可以在隧道势垒上或在自由层中停止。 第二实施例涉及在硬掩模层上形成第一平行线图案，并通过第一蚀刻步骤通过MTJ堆叠传送线图案。 平面绝缘层与线图案中的侧壁相邻地形成，然后形成第二平行线图案，其通过第二次蚀刻通过MTJ叠层转印以形成柱形图案。 蚀刻终点可以独立控制硬轴和易轴尺寸。

公开(公告)号：US20110129946A1

公开(公告)日：2011-06-02

申请号：US12931648

申请日：2011-02-07

申请人： Tom Zhong ,  Chyu-Jiuh Torng ,  Rongfu Xiao ,  Adam Zhong ,  Wai-Ming Johnson Kan ,  Daniel Liu

发明人： Tom Zhong ,  Chyu-Jiuh Torng ,  Rongfu Xiao ,  Adam Zhong ,  Wai-Ming Johnson Kan ,  Daniel Liu

IPC分类号： H01L21/00

CPC分类号： H01L27/228 ,  H01L43/12

摘要： A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.