公开(公告)号：US11043632B2

公开(公告)日：2021-06-22

申请号：US16573087

申请日：2019-09-17

申请人： Headway Technologies, Inc.

发明人： Vignesh Sundar ,  Guenole Jan ,  Dongna Shen ,  Yi Yang ,  Yu-Jen Wang

IPC分类号： H01L43/12 ,  H01L43/02 ,  H01L27/22

摘要： A first pattern is formed on an MTJ stack as a first array of first parallel bands. A first ion beam etching is performed on the MTJ stack using the first pattern wherein a tilt between an ion beam source and the substrate is maintained such that a horizontal component of the ion beam is parallel to the first parallel bands and the substrate is not rotated. Thereafter, a second pattern is formed on the MTJ stack as a second array of parallel bands wherein the second parallel bands are perpendicular to the first parallel bands. A second ion beam etching is performed using the second pattern wherein a tilt between an ion beam source and the substrate is maintained such that a horizontal component of the ion beam is parallel to the second parallel bands and wherein the substrate is not rotated to complete formation of the MTJ structure.

公开(公告)号：US20210135097A1

公开(公告)日：2021-05-06

申请号：US16672981

申请日：2019-11-04

申请人： Headway Technologies, Inc.

发明人： Dongna Shen ,  Yi Yang ,  Sahil Patel ,  Vignesh Sundar ,  Yu-Jen Wang

IPC分类号： H01L43/12 ,  H01L43/02

摘要： A method for fabricating a magnetic tunneling junction (MTJ) structure is described. A MTJ film stack is deposited on a bottom electrode on a substrate. The MTJ film stack is first ion beam etched (IBE) using a first angle and a first energy to form a MTJ device wherein conductive re-deposition forms on sidewalls of the MTJ device. Thereafter, the conductive re-deposition is oxidized. Thereafter, the MTJ device is second ion beam etched (IBE) at a second angle and a second energy to remove oxidized re-deposition.

公开(公告)号：US20210083180A1

公开(公告)日：2021-03-18

申请号：US16573087

申请日：2019-09-17

申请人： Headway Technologies, Inc.

发明人： Vignesh Sundar ,  Guenole Jan ,  Dongna Shen ,  Yi Yang ,  Yu-Jen Wang

IPC分类号： H01L43/12 ,  H01L27/22 ,  H01L43/02

摘要： A first pattern is formed on an MTJ stack as a first array of first parallel bands. A first ion beam etching is performed on the MTJ stack using the first pattern wherein a tilt between an ion beam source and the substrate is maintained such that a horizontal component of the ion beam is parallel to the first parallel bands and the substrate is not rotated. Thereafter, a second pattern is formed on the MTJ stack as a second array of parallel bands wherein the second parallel bands are perpendicular to the first parallel bands. A second ion beam etching is performed using the second pattern wherein a tilt between an ion beam source and the substrate is maintained such that a horizontal component of the ion beam is parallel to the second parallel bands and wherein the substrate is not rotated to complete formation of the MTJ structure.

公开(公告)号：US10756137B2

公开(公告)日：2020-08-25

申请号：US16215094

申请日：2018-12-10

申请人： Headway Technologies, Inc.

发明人： Yi Yang ,  Dongna Shen ,  Yu-Jen Wang

IPC分类号： H01L27/22 ,  H01L43/02 ,  H01L43/12 ,  H01L43/10 ,  H01L43/08

摘要： A MTJ stack comprising at least a pinned layer, a barrier layer, and a free layer is deposited on a bottom electrode. A top electrode layer, a carbon-based hard mask, and a dielectric hard mask are deposited in order on the MTJ stack. First, the hard masks and MTJ stack are etched. The etched MTJ stack has a first width. During the first etching, chemical damage forms on sidewalls of the MTJ stack. Next, the carbon-based hard mask is trimmed to a second width smaller than the first width. Then in a second etching, the top electrode and free layer of said MTJ stack not covered by the trimmed carbon-based hard mask are etched to complete formation of the MTJ structure wherein during the second etching of the free layer, chemical damage is removed from the free layer and metal re-deposition is formed on sidewalls of the free layer.

公开(公告)号：US20200212297A1

公开(公告)日：2020-07-02

申请号：US16236705

申请日：2018-12-31

申请人： Headway Technologies, Inc.

发明人： Yi Yang ,  Vignesh Sundar ,  Dongna Shen ,  Sahil Patel ,  Ru-Ying Tong ,  Yu-Jen Wang

IPC分类号： H01L43/12

摘要： A complementary metal oxide semiconductor (CMOS) device comprises a first metal line, a first metal via on the first metal line, a magnetic tunneling junction (MTJ) device on the first metal via wherein the first metal via acts as a bottom electrode for the MTJ device, a second metal via on the MTJ device, and a second metal line on the second metal via.

公开(公告)号：US20200185454A1

公开(公告)日：2020-06-11

申请号：US16215094

申请日：2018-12-10

申请人： Headway Technologies, Inc.

发明人： Yi Yang ,  Dongna Shen ,  Yu-Jen Wang

IPC分类号： H01L27/22 ,  H01L43/02 ,  H01L43/08 ,  H01L43/10 ,  H01L43/12

摘要： A MTJ stack comprising at least a pinned layer, a barrier layer, and a free layer is deposited on a bottom electrode. A top electrode layer, a carbon-based hard mask, and a dielectric hard mask are deposited in order on the MTJ stack. First, the hard masks and MTJ stack are etched. The etched MTJ stack has a first width. During the first etching, chemical damage forms on sidewalls of the MTJ stack. Next, the carbon-based hard mask is trimmed to a second width smaller than the first width. Then in a second etching, the top electrode and free layer of said MTJ stack not covered by the trimmed carbon-based hard mask are etched to complete formation of the MTJ structure wherein during the second etching of the free layer, chemical damage is removed from the free layer and metal re-deposition is formed on sidewalls of the free layer.

公开(公告)号：US20180358545A1

公开(公告)日：2018-12-13

申请号：US15619825

申请日：2017-06-12

申请人： Headway Technologies, Inc.

发明人： Vignesh Sundar ,  Yu-Jen Wang ,  Dongna Shen ,  Sahil Patel ,  Ru-Ying Tong

IPC分类号： H01L43/10 ,  H01L43/02 ,  H01L27/22 ,  H01L21/02 ,  G11C11/15 ,  G11C11/16

CPC分类号： H01L43/10 ,  C23C16/308 ,  C23C16/505 ,  G11C11/15 ,  G11C11/161 ,  H01L21/02126 ,  H01L21/02274 ,  H01L27/222 ,  H01L43/02 ,  H01L43/12

摘要： A plasma enhanced chemical vapor deposition (PECVD) method is disclosed for forming a SiON encapsulation layer on a magnetic tunnel junction (MTJ) sidewall that minimizes attack on the MTJ sidewall during the PECVD or subsequent processes. The PECVD method provides a higher magnetoresistive ratio for the MTJ than conventional methods after a 400° C. anneal. In one embodiment, the SiON encapsulation layer is deposited using a N2O:silane flow rate ratio of at least 1:1 but less than 15:1. A N2O plasma treatment may be performed immediately following the PECVD to ensure there is no residual silane in the SiON encapsulation layer. In another embodiment, a first (lower) SiON sub-layer has a greater Si content than a second (upper) SiON sub-layer. A second encapsulation layer is formed on the SiON encapsulation layer so that the encapsulation layers completely fill the gaps between adjacent MTJs.

公开(公告)号：US09871195B1

公开(公告)日：2018-01-16

申请号：US15465644

申请日：2017-03-22

申请人： Headway Technologies, Inc.

发明人： Yi Yang ,  Dongna Shen ,  Yu-Jen Wang

IPC分类号： H01L43/12 ,  H01L43/08 ,  H01L43/02

CPC分类号： H01L43/12 ,  G11B5/3163 ,  G11C11/161 ,  H01L43/08

摘要： A stack of MTJ layers is provided on a substrate comprising a bottom electrode, a pinned layer, a tunnel barrier layer, a free layer, and a top electrode. The MTJ stack is patterned to form a MTJ device wherein sidewall damage is formed on its sidewalls. A dielectric spacer is formed on the MTJ device. The dielectric spacer is etched away on horizontal surfaces wherein the dielectric spacer on the sidewalls is partially etched away. The remaining dielectric spacer covers the pinned layer and bottom electrode. The dielectric spacer is removed from the free layer or is thinner on the free layer than on the pinned layer and bottom electrode. Sidewall damage is thereafter removed from the free layer by applying a horizontal etching to the MTJ device wherein the pinned layer and bottom electrode are protected from etching by the dielectric spacer layer.

公开(公告)号：US09660177B2

公开(公告)日：2017-05-23

申请号：US14848378

申请日：2015-09-09

申请人： Headway Technologies, Inc.

发明人： Rao Annapragada ,  Yu-Jen Wang ,  Dongna Shen

IPC分类号： H01L41/22 ,  H01L43/12 ,  H01L41/12 ,  H01L43/08 ,  H01L41/47 ,  H01L41/06 ,  H01L27/22 ,  H01L43/02

CPC分类号： H01L41/47 ,  H01F41/308 ,  H01L27/224 ,  H01L41/06 ,  H01L41/12 ,  H01L43/02 ,  H01L43/08 ,  H01L43/12

摘要： An improved method for etching a magnetic tunneling junction (MTJ) structure is achieved. A stack of MTJ layers is provided on a bottom electrode. The MTJ stack is patterned to form a MTJ device wherein sidewall damage or sidewall redeposition is formed on sidewalls of the MTJ device. A dielectric layer is deposited on the MTJ device and the bottom electrode. The dielectric layer is etched away using ion beam etching at an angle relative to vertical of greater than 50 degrees wherein the dielectric layer on the sidewalls is etched away and wherein sidewall damage or sidewall redeposition is also removed and wherein some of the dielectric layer remains on horizontal surfaces of the bottom electrode.

公开(公告)号：US20160351798A1

公开(公告)日：2016-12-01

申请号：US14726545

申请日：2015-05-31

申请人： Headway Technologies, Inc.

发明人： Dongna Shen ,  Yu-Jen Wang ,  Jesmin Haq

IPC分类号： H01L43/12 ,  H01L43/08 ,  H01L43/02

CPC分类号： H01L43/12

摘要： A hard mask stack for etching a magnetic tunneling junction (MTJ) structure is described. An electrode layer is deposited on a stack of MTJ layers on a bottom electrode. A photoresist mask is formed on the electrode layer. The electrode layer is etched away where it is not covered by the photoresist mask to form a metal hard mask. The metal hard mask is passivated during or after etching to form a smooth hard mask profile. Thereafter, the photoresist mask is removed and the MTJ structure is etched using the metal hard mask wherein the metal hard mask remaining acts as a top electrode. The resulting MTJ device has smooth sidewalls and uniform device shape.

摘要翻译： 描述了用于蚀刻磁隧道结（MTJ）结构的硬掩模叠层。 电极层沉积在底部电极上的一层MTJ层上。 在电极层上形成光致抗蚀剂掩模。 电极层被蚀刻掉，其未被光致抗蚀剂掩模覆盖以形成金属硬掩模。 金属硬掩模在蚀刻期间或之后被钝化以形成光滑的硬掩模轮廓。 此后，去除光致抗蚀剂掩模，并使用金属硬掩模蚀刻MTJ结构，其中剩余的金属硬掩模用作顶部电极。 所得MTJ装置具有平滑的侧壁和均匀的装置形状。