公开(公告)号：US08058698B2

公开(公告)日：2011-11-15

申请号：US12803189

申请日：2010-06-21

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

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

IPC: H01L29/82 ,  G11C11/00

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

Abstract: An 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 is 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 has a low Gilbert damping factor and a 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.

Abstract translation: 利用转移自旋角动量作为改变自由层的磁矩方向的机构的STT-MTJ MRAM单元。 该器件包括形成在钉扎层的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，是非晶形的自由层 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层。 自由层具有低的吉尔伯特衰减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：US20110133300A1

公开(公告)日：2011-06-09

申请号：US12927670

申请日：2010-11-19

Applicant: Rongfu Xiao ,  Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jinh Torng ,  Tom Zhong ,  Witold Kula ,  Terry Kin Ting Ko ,  Wei Cao ,  Wai-Ming J. Kan ,  Liubo Hong

Inventor： Rongfu Xiao ,  Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jinh Torng ,  Tom Zhong ,  Witold Kula ,  Terry Kin Ting Ko ,  Wei Cao ,  Wai-Ming J. Kan ,  Liubo Hong

IPC: H01L29/82

CPC classification number: H01L43/12 ,  G11C11/161 ,  H01L43/08

Abstract: A multi-layered bottom electrode for an MTJ device on a silicon nitride substrate is described. It comprises a bilayer of alpha tantalum on ruthenium which in turn lies on a nickel chrome layer over a second tantalum layer.

Abstract translation: 描述了用于氮化硅衬底上的MTJ器件的多层底电极。 它包括在钌上的α钽的双层，其又位于第二钽层上的镍铬层上。

公开(公告)号：US20110076785A1

公开(公告)日：2011-03-31

申请号：US12927615

申请日：2010-11-19

Applicant: Rongfu Xiao ,  Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jinh Torng ,  Tom Zhong ,  Witold Kula ,  Terry Kin Ting Ko ,  Wei Cao ,  Wai-Ming J. Kan ,  Liubo Hong

Inventor： Rongfu Xiao ,  Cheng T. Horng ,  Ru-Ying Tong ,  Chyu-Jinh Torng ,  Tom Zhong ,  Witold Kula ,  Terry Kin Ting Ko ,  Wei Cao ,  Wai-Ming J. Kan ,  Liubo Hong

IPC: H01L21/00

CPC classification number: H01L43/12 ,  G11C11/161 ,  H01L43/08

Abstract: Formation of a bottom electrode for an MTJ device on a silicon nitride substrate is facilitated by including a protective coating that is partly consumed during etching of the alpha tantalum portion of said bottom electrode. Adhesion to SiN is enhanced by using a TaN/NiCr bilayer as “glue”.

Abstract translation: 在氮化硅衬底上形成用于MTJ器件的底部电极通过包括在所述底部电极的α钽部分的蚀刻期间部分消耗的保护涂层来促进。 通过使用TaN / NiCr双层作为“胶”来增强对SiN的附着力。

公开(公告)号：US07713755B1

公开(公告)日：2010-05-11

申请号：US12316501

申请日：2008-12-11

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

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

IPC: H01L21/00

CPC classification number: H01L43/12

Abstract: 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.

Abstract translation: 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

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

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

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

CPC classification number: H01L43/12 ,  H01L43/08

Abstract: 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.

Abstract translation: 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：US20090108383A1

公开(公告)日：2009-04-30

申请号：US11981127

申请日：2007-10-31

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

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

IPC: H01L29/82 ,  H01L21/8246

CPC classification number: H01L43/10 ,  B82Y10/00 ,  H01L27/228 ,  H01L43/08 ,  H01L43/12

Abstract: 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.

Abstract translation: 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 nmx200 nm椭圆形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：US06954342B2

公开(公告)日：2005-10-11

申请号：US09846707

申请日：2001-04-30

Applicant: Witold Kula ,  Alexander Zeltser

Inventor： Witold Kula ,  Alexander Zeltser

IPC: G01R33/09 ,  G11B5/012 ,  G11B5/39 ,  G11B5/33

CPC classification number: B82Y25/00 ,  B82Y10/00 ,  G01R33/093 ,  G11B5/012 ,  G11B5/3903 ,  G11B2005/3996

Abstract: A spin valve sensor system and a method for fabricating the same are provided. Such spin valve sensor includes a pinned layer having a pinned layer magnetization. Also included is a free layer disposed adjacent the pinned layer. The free layer has a free layer magnetization perpendicular to the pinned layer magnetization in the absence of an external field. A pinning layer is disposed adjacent the pinned layer for fixing the pinned layer magnetization. Further included is an underlayer disposed adjacent the pinning layer. Such underlayer comprises NiFeX. Disposed adjacent the underlayer and the pinning layer is an upper layer. The upper layer comprises a material selected from the group consisting of NiFe and CoFe for increasing a GMR ratio associated with the SV sensor.

Abstract translation: 提供一种自旋阀传感器系统及其制造方法。 这种自旋阀传感器包括具有钉扎层磁化的钉扎层。 还包括邻近被钉扎层设置的自由层。 自由层在没有外部场的情况下具有垂直于被钉扎层磁化的自由层的磁化。 钉扎层邻近被钉扎层设置以固定被钉扎层的磁化。 还包括设置在钉扎层附近的底层。 这种底层包括NiFeX。 邻近下层设置并且钉扎层是上层。 上层包括选自NiFe和CoFe的材料，用于增加与SV传感器相关联的GMR比。

公开(公告)号：US06913782B2

公开(公告)日：2005-07-05

申请号：US10309938

申请日：2002-12-03

Applicant: Witold Kula ,  Alexander Michael Zeltser

Inventor： Witold Kula ,  Alexander Michael Zeltser

IPC: G01R33/09 ,  G11B5/31 ,  G11B5/39 ,  G11B5/40 ,  H01L43/08 ,  H01L43/12 ,  B05D3/00

CPC classification number: B82Y25/00 ,  B82Y10/00 ,  G01R33/093 ,  G11B5/3133 ,  G11B5/3903 ,  G11B5/3909 ,  G11B5/40 ,  G11B2005/3996

Abstract: A magnetoresistance sensor is fabricated using a sensor structure including a free layer deposited upon a lower layered structure and depositing an oxide structure overlying the free layer. The depositing of the oxide structure includes the steps of depositing a buffer layer overlying the free layer, wherein the buffer layer is a buffer-layer metal when deposited, depositing an overlayer overlying and contacting the buffer layer, the overlayer being an overlayer metallic oxide of an overlayer metal, and oxidizing the buffer layer to form a buffer layer metallic oxide.

Abstract translation: 使用包括沉积在较低层结构上的自由层并沉积覆盖自由层的氧化物结构的传感器结构来制造磁阻传感器。 氧化物结构的沉积包括沉积覆盖自由层的缓冲层的步骤，其中当沉积时缓冲层是缓冲层金属，沉积覆盖层并接触缓冲层的覆盖层，所述覆盖层是覆盖层的金属氧化物 覆盖金属，氧化缓冲层形成缓冲层金属氧化物。

公开(公告)号：US06867951B1

公开(公告)日：2005-03-15

申请号：US09614945

申请日：2000-07-12

Applicant: Witold Kula

Inventor： Witold Kula

IPC: G11B5/39

CPC classification number: G11B5/3903

Abstract: In a spin valve, an underlayer is made of oxygen-rich nickel oxide to enhance the giant magnetoresistive ratio (ΔR/R). The oxygen-rich nickel oxide film is made using reactive sputtering of a nickel target in an oxygen-rich sputtering atmosphere consisting substantially of pure oxygen and argon gases. The total pressure of the oxygen-rich atmosphere is reduced during the oxygen-rich nickel oxide film formation to additionally enhance the ΔR/R value. A spin valve including two adjacent oxygen-rich nickel oxide underlayers provides a higher ΔR/R ratio at a given pinning strength Hua than does a spin valve having only one oxygen-rich nickel oxide underlayer.

Abstract translation: 在自旋阀中，底层由富氧氧化镍制成，以增强巨磁阻比（DeltaR / R）。 富氧镍氧化物膜是使用基于纯氧和氩气组成的富氧溅射气氛中的镍靶的反应溅射制成的。 在富氧氧化镍膜形成期间，富氧气氛的总压降低，以增加ΔR/ R值。 包括两个相邻的富氧氧化镍底层的自旋阀在给定的钉扎强度华氏度下提供比仅具有一个富氧氧化镍底层的自旋阀更高的ΔR/ R比。

公开(公告)号：US09159908B2

公开(公告)日：2015-10-13

申请号：US13068222

申请日：2011-05-05

Applicant: Wei Cao ,  Witold Kula

Inventor： Wei Cao ,  Witold Kula

IPC: H01L43/10 ,  H01L43/08 ,  G11C11/16 ,  H01L43/12 ,  H01F41/30 ,  B82Y40/00 ,  H01F10/187 ,  H01F10/32

CPC classification number: H01L43/10 ,  B82Y40/00 ,  G11C11/161 ,  H01F10/187 ,  H01F10/3254 ,  H01F10/3272 ,  H01F10/3295 ,  H01F41/303 ,  H01L43/08 ,  H01L43/12

Abstract: A magnetic tunneling junction (MTJ) in an MRAM array is disclosed with a composite free layer having a FL1/FL2/FL3 configuration where FL1 and FL2 are crystalline magnetic layers and FL3 is an amorphous NiFeX layer for improved bit switching performance. FL1 layer is CoFe which affords a high magnetoresistive (MR) ratio when forming an interface with a MgO tunnel barrier. FL2 is Fe to improve switching performance. NiFeX thickness where X is Hf is preferably between 20 to 40 Angstroms to substantially reduce bit line switching current and number of shorted bits. Annealing at 330° C. to 360° C. provides a high MR ratio of 190%. Furthermore, low Hc and Hk are simultaneously achieved with improved bit switching performance and fewer shorts without compromising other MTJ properties such as MR ratio. As a result of high MR ratio and lower bit-to-bit resistance variation, higher reading margin is realized.

Abstract translation: 公开了一种具有FL1 / FL2 / FL3配置的复合自由层的MRAM阵列中的磁隧道结（MTJ），其中FL1和FL2是结晶磁性层，FL3是非晶NiFeX层，用于改善位切换性能。 FL1层是当与MgO隧道势垒形成界面时提供高磁阻（MR）比的CoFe。 FL2是Fe提高开关性能。 其中X为Hf的NiFeX厚度优选在20至40埃之间，以显着降低位线切换电流和短路位数。 在330℃至360℃退火提供190％的高MR比。 此外，低Hc和Hk同时实现，具有改进的位切换性能和更短的短路，而不会影响其他MTJ特性，例如MR比。 由于高MR比和较低的比特电阻变化，实现了更高的读取余量。