公开(公告)号：US07696551B2

公开(公告)日：2010-04-13

申请号：US11901999

申请日：2007-09-20

申请人： Rongfu Xiao ,  Chyu-Jiuh Torng ,  Tom Zhang ,  Witold Kula ,  Adam Zhang

发明人： Rongfu Xiao ,  Chyu-Jiuh Torng ,  Tom Zhang ,  Witold Kula ,  Adam Zhang

IPC分类号： H01L21/00

CPC分类号： H01L43/12 ,  Y10T428/24736

摘要： A composite hard mask is disclosed that enables sub-100 nm sized MTJ cells to be formed for advanced devices such as spin torque MRAMs. The hard mask has a lower non-magnetic metallic layer such as Ru to magnetically isolate an overlying middle metallic spacer such as MnPt from an underlying free layer. The middle metallic spacer provides a height margin during subsequent processing to avoid shorting between a bit line and the MTJ cell in the final device. An upper conductive layer may be made of Ta and is thin enough to allow a MTJ pattern in a thin overlying photoresist layer to be transferred through the Ta during a fluorocarbon etch without consuming all of the photoresist. The MTJ pattern is transferred through the remaining hard mask layers and underlying MTJ stack of layers with a second etch step using a C, H, and O etch gas composition.

摘要翻译： 公开了一种复合硬掩模，其能够为高级装置（例如自旋扭矩MRAM）形成次100nm大小的MTJ电池。 硬掩模具有较低的非磁性金属层，例如Ru，以将下层的中间金属间隔物（例如MnPt）与下层的自由层磁隔离。 中间金属间隔件在后续处理期间提供高度余量以避免位线和最终装置中的MTJ单元之间的短路。 上导电层可以由Ta制成，并且足够薄以使氟薄膜蚀刻中的薄覆盖光致抗蚀剂层中的MTJ图案能够通过Ta Ta传输而不消耗所有的光致抗蚀剂。 使用C，H和O蚀刻气体组合物，通过第二蚀刻步骤将MTJ图案转移通过剩余的硬掩模层和下面的MTJ堆叠层。

公开(公告)号：US07936027B2

公开(公告)日：2011-05-03

申请号：US12006889

申请日：2008-01-07

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

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

IPC分类号： G11C11/02

CPC分类号： H01L43/12 ,  H01L43/08

摘要： An MTJ cell without footings and free from electrical short-circuits across a tunneling barrier layer is formed by using a Ta hard mask layer and a combination of etches. A first etch patterns the Ta hard mask, while a second etch uses O2 applied in a single high power process at two successive different power levels. A first power level of between approximately 200 W and 500 W removes BARC, photoresist and Ta residue from the first etch, the second power level, between approximately 400 W and 600 W continues an etch of the stack layers and forms a protective oxide around the etched sides of the stack. Finally, an etch using a carbon, hydrogen and oxygen gas completes the etch while the oxide layer protects the cell from short-circuits across the lateral edges of the barrier layer.

摘要翻译： 通过使用Ta硬掩模层和蚀刻的组合，形成没有底脚并且穿过隧道势垒层的电短路的MTJ电池。 第一蚀刻图案Ta硬掩模，而第二蚀刻使用在两个连续的不同功率水平下在单个高功率过程中施加的O2。 在大约200W至500W之间的第一功率电平从第一蚀刻去除BARC，光致抗蚀剂和Ta残留物，第二功率电平在大约400W至600W之间，继续蚀刻叠层，并在其周围形成保护氧化物 蚀刻边的堆叠。 最后，使用碳，氢和氧气的蚀刻完成了蚀刻，而氧化物层保护电池免受横跨阻挡层的侧边缘的短路。

公开(公告)号：US07713755B1

公开(公告)日：2010-05-11

申请号：US12316501

申请日：2008-12-11

申请人： Rongfu Xiao ,  Ruth Tong ,  Witold Kula ,  Chyu-Jiuh Torng

发明人： Rongfu Xiao ,  Ruth Tong ,  Witold Kula ,  Chyu-Jiuh Torng

IPC分类号： H01L21/00

CPC分类号： H01L43/12

摘要： A high-amplitude magnetic angle sensor is described along with a process for its manufacture. A thin tantalum nitride hard mask, used to pattern the device, is left in place within the completed structure but, by first converting most of it to tantalum oxide, its effect on current shunting is greatly reduced.

摘要翻译： 描述了高振幅磁角传感器及其制造方法。 用于将器件图案化的薄氮化钽硬掩模在完成的结构内留在原位，但是通过首先将其大部分转换为氧化钽，其对电流分流的影响大大降低。

公开(公告)号：US20090173977A1

公开(公告)日：2009-07-09

申请号：US12006889

申请日：2008-01-07

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

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

IPC分类号： H01L43/00 ,  H01L29/82 ,  H01L43/12 ,  H01L21/467

CPC分类号： H01L43/12 ,  H01L43/08

摘要： An MTJ cell without footings and free from electrical short-circuits across a tunneling barrier layer is formed by using a Ta hard mask layer and a combination of etches. A first etch patterns the Ta hard mask, while a second etch uses O2 applied in a single high power process at two successive different power levels. A first power level of between approximately 200 W and 500 W removes BARC, photoresist and Ta residue from the first etch, the second power level, between approximately 400 W and 600 W continues an etch of the stack layers and forms a protective oxide around the etched sides of the stack. Finally, an etch using a carbon, hydrogen and oxygen gas completes the etch while the oxide layer protects the cell from short-circuits across the lateral edges of the barrier layer.

摘要翻译： 通过使用Ta硬掩模层和蚀刻的组合，形成没有底脚并且穿过隧道势垒层的电短路的MTJ电池。 第一蚀刻图案Ta硬掩模，而第二蚀刻使用在两个连续的不同功率水平下在单个高功率过程中施加的O2。 在大约200W至500W之间的第一功率电平从第一蚀刻去除BARC，光致抗蚀剂和Ta残留物，第二功率电平在大约400W至600W之间，继续蚀刻叠层，并在其周围形成保护氧化物 蚀刻边的堆叠。 最后，使用碳，氢和氧气的蚀刻完成了蚀刻，而氧化物层保护电池免受横跨阻挡层的侧边缘的短路。

公开(公告)号：US20090078927A1

公开(公告)日：2009-03-26

申请号：US11901999

申请日：2007-09-20

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

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

IPC分类号： H01L29/06 ,  H01L21/02

CPC分类号： H01L43/12 ,  Y10T428/24736

摘要： A composite hard mask is disclosed that enables sub-100 nm sized MTJ cells to be formed for advanced devices such as spin torque MRAMs. The hard mask has a lower non-magnetic metallic layer such as Ru to magnetically isolate an overlying middle metallic spacer such as MnPt from an underlying free layer. The middle metallic spacer provides a height margin during subsequent processing to avoid shorting between a bit line and the MTJ cell in the final device. An upper conductive layer may be made of Ta and is thin enough to allow a MTJ pattern in a thin overlying photoresist layer to be transferred through the Ta during a fluorocarbon etch without consuming all of the photoresist. The MTJ pattern is transferred through the remaining hard mask layers and underlying MTJ stack of layers with a second etch step using a C, H, and O etch gas composition.

摘要翻译： 公开了一种复合硬掩模，其能够为高级装置（例如自旋扭矩MRAM）形成次100nm大小的MTJ电池。 硬掩模具有较低的非磁性金属层，例如Ru，以将下层的中间金属间隔物（例如MnPt）与下层的自由层磁隔离。 中间金属间隔件在后续处理期间提供高度余量以避免位线和最终装置中的MTJ单元之间的短路。 上导电层可以由Ta制成，并且足够薄以使氟薄膜蚀刻中的薄覆盖光致抗蚀剂层中的MTJ图案能够通过Ta Ta传输而不消耗所有的光致抗蚀剂。 使用C，H和O蚀刻气体组合物，通过第二蚀刻步骤将MTJ图案转移通过剩余的硬掩模层和下面的MTJ堆叠层。

公开(公告)号：US20120028373A1

公开(公告)日：2012-02-02

申请号：US12804840

申请日：2010-07-30

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

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

IPC分类号： H01L43/12 ,  B32B5/00 ,  B32B7/02 ,  B32B15/04

CPC分类号： H01L43/12 ,  Y10T428/12535 ,  Y10T428/24975 ,  Y10T428/266 ,  Y10T428/31504 ,  Y10T428/31678

摘要： A composite hard mask is disclosed that prevents build up of metal etch residue in a MRAM device during etch processes that define an MTJ shape. As a result, MTJ shape integrity is substantially improved. The hard mask has a lower non-magnetic spacer, a middle conductive layer, and an upper sacrificial dielectric layer. The non-magnetic spacer serves as an etch stop during a pattern transfer with fluorocarbon plasma through the conductive layer. A photoresist pattern is transferred through the dielectric layer with a first fluorocarbon etch. Then the photoresist is removed and a second fluorocarbon etch transfers the pattern through the conductive layer. The dielectric layer protects the top surface of the conductive layer during the second fluorocarbon etch and during a substantial portion of a third RIE step with a gas comprised of C, H, and O that transfers the pattern through the underlying MTJ layers.

摘要翻译： 公开了一种复合硬掩模，其防止在限定MTJ形状的蚀刻工艺期间在MRAM器件中积累金属蚀刻残留物。 结果，MTJ形状完整性得到显着提高。 硬掩模具有较低的非磁性间隔物，中间导电层和上部牺牲介电层。 在通过导电层的氟碳等离子体的图案转印期间，非磁性间隔物用作蚀刻停止层。 光致抗蚀剂图案通过第一氟碳蚀刻转移通过电介质层。 然后去除光致抗蚀剂，并且第二氟碳蚀刻将图案转移通过导电层。 介电层在第二次氟碳蚀刻期间保护导电层的顶表面，并在第三次RIE步骤的大部分期间保护由C，H和O组成的气体，以将图案转移通过下面的MTJ层。

公开(公告)号：US08722543B2

公开(公告)日：2014-05-13

申请号：US12804840

申请日：2010-07-30

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

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

IPC分类号： H01L21/302 ,  H01L21/00

CPC分类号： H01L43/12 ,  Y10T428/12535 ,  Y10T428/24975 ,  Y10T428/266 ,  Y10T428/31504 ,  Y10T428/31678

摘要： A composite hard mask is disclosed that prevents build up of metal etch residue in a MRAM device during etch processes that define an MTJ shape. As a result, MTJ shape integrity is substantially improved. The hard mask has a lower non-magnetic spacer, a middle conductive layer, and an upper sacrificial dielectric layer. The non-magnetic spacer serves as an etch stop during a pattern transfer with fluorocarbon plasma through the conductive layer. A photoresist pattern is transferred through the dielectric layer with a first fluorocarbon etch. Then the photoresist is removed and a second fluorocarbon etch transfers the pattern through the conductive layer. The dielectric layer protects the top surface of the conductive layer during the second fluorocarbon etch and during a substantial portion of a third RIE step with a gas comprised of C, H, and O that transfers the pattern through the underlying MTJ layers.

摘要翻译： 公开了一种复合硬掩模，其防止在限定MTJ形状的蚀刻工艺期间在MRAM器件中积累金属蚀刻残留物。 结果，MTJ形状完整性得到显着提高。 硬掩模具有较低的非磁性间隔物，中间导电层和上部牺牲介电层。 在通过导电层的氟碳等离子体的图案转印期间，非磁性间隔物用作蚀刻停止层。 光致抗蚀剂图案通过第一氟碳蚀刻转移通过电介质层。 然后去除光致抗蚀剂，并且第二氟碳蚀刻将图案转移通过导电层。 介电层在第二次氟碳蚀刻期间保护导电层的顶表面，并在第三次RIE步骤的大部分期间保护由C，H和O组成的气体，以将图案转移通过下面的MTJ层。

公开(公告)号：US08372661B2

公开(公告)日：2013-02-12

申请号：US11981127

申请日：2007-10-31

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

CPC分类号： H01L43/10 ,  B82Y10/00 ,  H01L27/228 ,  H01L43/08 ,  H01L43/12

摘要： A STT-RAM MTJ that minimizes spin-transfer magnetization switching current (Jc) is disclosed. The MTJ has a MgO tunnel barrier layer formed with a natural oxidation process to achieve a low RA (10 ohm-um2) and a Fe or Fe/CoFeB/Fe free layer which provides a lower intrinsic damping constant than a CoFeB free layer. A Fe, FeB, or Fe/CoFeB/Fe free layer when formed with a MgO tunnel barrier (radical oxidation process) and a CoFeB AP1 pinned layer in a MRAM MTJ stack annealed at 360° C. provides a high dR/R (TMR)>100% and a substantial improvement in read margin with a TMR/Rp_cov=20. High speed measurement of 100 nm×200 nm oval STT-RAM MTJs has shown a Jc0 for switching a Fe free layer is one half that for switching an amorphous CO40Fe40B20 free layer. A Fe/CoFeB/Fe free layer configuration allows the Hc value to be increased for STT-RAM applications.

摘要翻译： 公开了使自旋转移磁化开关电流（Jc）最小化的STT-RAM MTJ。 MTJ具有形成有自然氧化工艺的MgO隧道阻挡层，以实现低的RA（10欧姆 - um2）和不含CoFeB自由层的较低的固有阻尼常数的Fe或Fe / CoFeB / Fe自由层。 当在360℃退火的MRAM MTJ堆叠中形成具有MgO隧道势垒（自由基氧化法）和CoFeB AP1钉扎层的Fe，FeB或Fe / CoFeB / Fe自由层时，提供高dR / R（TMR ）> 100％，TMR / Rp_cov = 20时读取余量大幅度提高。 100 nm×200 nm椭圆STT-RAM MTJ的高速测量显示，用于切换无Fe层的Jc0是用于切换无定形CO40Fe40B20自由层的一半。 Fe / CoFeB / Fe自由层配置允许为STT-RAM应用增加Hc值。

公开(公告)号：US20100258889A1

公开(公告)日：2010-10-14

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： An STT-MTJ MRAM cell utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The cell 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 composite tri-layer 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： STT-MTJ MRAM单元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。 电池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，复合三层自由层 其包括分别在3和6埃厚度的Fe的两个结晶层之间形成的约20埃厚度的Co60Fe20B20的非晶层。 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：US20080088986A1

公开(公告)日：2008-04-17

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： G11B5/33 ,  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。