公开(公告)号：WO2018175095A1

公开(公告)日：2018-09-27

申请号：PCT/US2018/020854

申请日：2018-03-05

Applicant: HEADWAY TECHNOLOGIES, INC.

Inventor： TENG, Zhongjian ,  ZHONG, Tom ,  HAQ, Jesmin

IPC: H01L43/12

Abstract: The proposed method for patterning a magnetic tunneling junction (MTJ) structure comprises providing a patterned mask (18) on a MTJ layer stack (16) formed over a bottom electrode (12) on a wafer (10), etching the stack to form a MTJ device, and removing sidewall damage (22) on the MTJ device by a physical treatment, preferably by using a slurry (27, 47) in a CMP or ultrasonic cleaning tool which physically attacks and removes the sidewall damage.

公开(公告)号：WO2019094577A1

公开(公告)日：2019-05-16

申请号：PCT/US2018/059802

申请日：2018-11-08

Applicant: HEADWAY TECHNOLOGIES, INC.

Inventor： HAQ, Jesmin ,  ZHONG, Tom ,  TENG, Zhongjian ,  LAM, Vinh ,  YANG, Yi

IPC: H01L43/08 ,  H01L43/12

Abstract: A layered thin film device, such as a MTJ (Magnetic Tunnel Junction) device can be customized in shape by sequentially forming its successive layers over a symmetrically curved electrode. By initially shaping the electrode to have a concave or convex surface, the sequentially formed layers conform to that shape and acquire it and are subject to stresses that cause various crystal defects to migrate away from the axis of symmetry, leaving the region immediately surrounding the axis of symmetry relatively defect free. The resulting stack can then be patterned to leave only the region that is relatively defect free.

公开(公告)号：WO2019018069A1

公开(公告)日：2019-01-24

申请号：PCT/US2018/035101

申请日：2018-05-30

Applicant: HEADWAY TECHNOLOGIES, INC.

Inventor： HAQ, Jesmin ,  ZHONG, Tom ,  TENG, Zhongjian

IPC: H01L43/08 ,  H01L43/12

Abstract: A process flow for forming a magnetic tunnel junction (MTJ) cell (47) that is self-aligned to an underlying bottom electrode BE (35, 36) is disclosed. The BE is comprised of a lower BE layer (35) having a first width (wl), and an upper (second) BE layer (36) with a second width (w2) where w2 > wl. Preferably, the BE has a T shape. A stack of MTJ layers including an uppermost hard mask (46) is deposited on the BE and has width w2 because of a self-aligned deposition process. A dummy MTJ stack (49) is also formed around the first BE layer. An ion beam etch where ions are at an incident angle

公开(公告)号：WO2019133868A1

公开(公告)日：2019-07-04

申请号：PCT/US2018/067951

申请日：2018-12-28

Applicant: HEADWAY TECHNOLOGIES, INC.

Inventor： ZHONG, Tom ,  HAQ, Jesmin ,  TENG, Zhongjian

IPC: H01L43/08 ,  H01L43/10 ,  H01L43/12 ,  G11C11/16 ,  H01L27/22

Abstract: An STT-MRAM device incorporating a multiplicity of MTJ junctions is encapsulated so that it dissipates heat produced by repeated read/write processes and is simultaneously shielded from external magnetic fields of neighboring devices. In addition, the encapsulation layers can be structured to reduced top lead stresses that have been shown to affect DR/R and Hc. We provide a device design and its method of fabrication that can simultaneously address all of these problems.

公开(公告)号：WO2018186983A1

公开(公告)日：2018-10-11

申请号：PCT/US2018/021286

申请日：2018-03-07

Applicant: HEADWAY TECHNOLOGIES, INC.

Inventor： HAQ, Jesmin ,  ZHONG, Tom ,  TENG, Zhongjian ,  SHEN, Dongna

IPC: H01L43/12 ,  H01L43/08

Abstract: A method for etching a magnetic tunneling junction (MTJ) structure is described. A bottom electrode layer (12) is provided on a substrate (10). A seed layer (16) is deposited on the bottom electrode layer. The seed layer and bottom electrode layer are patterned. A dielectric layer is deposited over the patterned seed layer and bottom electrode layer and planarized wherein the seed layer is exposed. Thereafter, a stack (30) of MTJ layers is deposited on the patterned seed layer comprising a pinned layer (18), a tunnel barrier layer (20), and a free layer (22). The MTJ stack is then patterned to form a MTJ device. Because the seed layer was patterned before the MTJ patterning step, the exposure of the device to etching plasma gases is shortened and thus, etch damage is minimized.