DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 4/01/2026 has been entered. Currently, claims 1-20 are pending.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-5, 10-15 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Saito et al. in US 2025/0031581 (hereinafter Saito).
Regarding claim 1, Saito disclose a magnetic tunneling junction device (Saito’s par. 1-2) comprising:
a synthetic antiferromagnet (Saito’s Fig. 23B and par. 211: see SAF formed by layers 52-56);
a free layer on the synthetic antiferromagnet (Saito’s Fig. 23B and por. 212: recording layer 57) and having a variable magnetization direction (Saito’s par. 213);
a separation metal layer between the synthetic antiferromagnet and the free layer (Saito’s Fig. 23B and par. 211-212: see 61), the separation metal layer configured to apply a current to the synthetic antiferromagnet (Saito’s Fig. 23B and par. 212, 142);
a pinned layer on the separation metal layer (Saito’s Fig. 23B and par. 213: reference layer 59) and having a pinned magnetization direction (Saito’s par. 2); and
an oxide layer between the free layer and the pinned layer (Saito’s Fig. 23B and par. 213: tunnel barrier layer 58 made of oxide materials per par. 141, 30),
wherein the synthetic antiferromagnet (Saito’s Fig. 23B: see layers 52-56) comprises
a first ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 52),
a non-magnetic metal layer on the first ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 53 or stack 53-55), and
a second ferromagnetic layer on the non-magnetic metal layer (Saito’s Fig. 23B and par. 211: see 56), and
wherein the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Fig. 23B: layers 52 and 56 respectively) are in a magnetic field considered to be Dzyaloshinskii-Moriya (DM) interaction (Saito’s par. 214: Dzyaloshinskii-Moriya (DM) interaction) such that magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Figs. 23B, 2A-2B) are opposite each other in an in-plane direction (Saito’s Figs. 23B, 2A-2B and par. 140, 210) and are configured to be inclined with respect to a direction of the current applied to the synthetic antiferromagnet through the separation metal layer (Saito’s Figs. 23B, 2A-2B and par. 51, 212).
Saito fails to explicitly disclose the first the first ferromagnetic layer and the second ferromagnetic layer are in a stable state.
However, because Saito does disclose the first ferromagnetic layer and the second ferromagnetic layer are in a magnetic field considered to be Dzyaloshinskii-Moriya (DM) interaction (Saito’s par. 214) and with the DMI interaction achieving stable magnetization (Saito’s par. 235-238: DM interaction and stable magnetization even when a pulse current is repeated), therefore it would have been obvious to one of ordinary skill in the art that the DM interaction results in a stable state, in order to obtain the predictable result of stable magnetization switching when a pulse current is applied when the DM interaction exists (Saito’s par. 237-238).
By doing such modification, Saito discloses:
the first ferromagnetic layer and the second and the second ferromagnetic layer (Saito’s Fig. 23B: layers 52 and 56 respectively) are in a stable state (Saito’s par. 214: Dzyaloshinskii-Moriya (DM) interaction which results in stable magnetization per par. 235-238) such that magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Figs. 23B, 2A-2B) are opposite each other in an in-plane direction (Saito’s Figs. 23B, 2A-2B and par. 140, 210) and are configured to be aligned to be inclined with respect to a direction of the current applied to the synthetic antiferromagnet through the separation metal layer (Saito’s Figs. 23B, 2A-2B and par. 51, 212).
Regarding claim 11, Saito discloses a memory device (Saito’s par. 9-10) comprising:
a plurality of memory cells (Saito’s par. 161: plurality of MTJ elements), each of the plurality of memory cells comprising a magnetic tunneling junction device (Saito’s par. 161: plurality of MTJ elements) and a switching device connected to the magnetic tunneling junction device (Saito’s Figs. 1B, 23B: see Tr1), wherein the magnetic tunneling junction device (Saito’s par. 1-2) comprises
a synthetic antiferromagnet (Saito’s Fig. 23B and par. 211: see SAF formed by layers 52-56),
a free layer on the synthetic antiferromagnet (Saito’s Fig. 23B and por. 212: recording layer 57) and having a variable magnetization direction(Saito’s par. 213),
a separation metal layer between the synthetic antiferromagnet and the free layer (Saito’s Fig. 23B and par. 211-212: see 61), the separation metal layer configured to apply a current, received from the switching device (Saito’s Fig. 23B and par. 142, from Tr1), to the synthetic antiferromagnet (Saito’s Fig. 23B and par. 212, 142),
a pinned layer on the free layer (Saito’s Fig. 23B and par. 213: reference layer 59) and having a pinned magnetization direction (Saito’s par. 2), and
an oxide layer between the free layer and the pinned layer (Saito’s Fig. 23B and par. 213: tunnel barrier layer 58 made of oxide materials per par. 141, 30), and
wherein the synthetic antiferromagnet (Saito’s Fig. 23B: see layers 52-56) comprises
a first ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 52),
a non-magnetic metal layer on the first ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 53 or stack 53-55), and
a second ferromagnetic layer on the non-magnetic metal layer (Saito’s Fig. 23B and par. 211: see 56), and
wherein the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Fig. 23B: layers 52 and 56 respectively) are in a magnetic field considered to be Dzyaloshinskii-Moriya (DM) interaction (Saito’s par. 214: Dzyaloshinskii-Moriya (DM) interaction) such that magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Figs. 23B, 2A-2B) are opposite each other in an in-plane direction (Saito’s Figs. 23B, 2A-2B and par. 140, 210) and are configured to be inclined with respect to a direction of the current applied to the synthetic antiferromagnet through the separation metal layer (Saito’s Figs. 23B, 2A-2B and par. 51, 212).
Saito fails to explicitly disclose the first the first ferromagnetic layer and the second ferromagnetic layer are in a stable state.
However, because Saito does disclose the first ferromagnetic layer and the second ferromagnetic layer are in a magnetic field considered to be Dzyaloshinskii-Moriya (DM) interaction (Saito’s par. 214) and with the DMI interaction achieving stable magnetization (Saito’s par. 235-238: DM interaction and stable magnetization even when a pulse current is repeated), therefore it would have been obvious to one of ordinary skill in the art that the DM interaction results in a stable state, in order to obtain the predictable result of stable magnetization switching when a pulse current is applied when the DM interaction exists (Saito’s par. 237-238).
By doing such modification, Saito discloses:
the first ferromagnetic layer and the second and the second ferromagnetic layer (Saito’s Fig. 23B: layers 52 and 56 respectively) are in a stable state (Saito’s par. 214: Dzyaloshinskii-Moriya (DM) interaction which results in stable magnetization per par. 235-238) such that magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer (Saito’s Figs. 23B, 2A-2B) are opposite each other in an in-plane direction (Saito’s Figs. 23B, 2A-2B and par. 140, 210) and are configured to be aligned to be inclined with respect to a direction of the current applied to the synthetic antiferromagnet through the separation metal layer (Saito’s Figs. 23B, 2A-2B and par. 51, 212).
Regarding claims 2 and 12, Saito fails to explicitly disclose the first ferromagnetic layer and the second ferromagnetic layer each include an alloy of a ferromagnetic metal and a non-magnetic metal.
However, Saito does disclose a material for a ferromagnetic layer to be CoFeBo, FeB or CoB (Saito’s par. 153 referring to ferromagnetic layer 28).
Therefore, it would have been obvious to one of ordinary skill in the art, that the first ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 52) and the second ferromagnetic layer (Saito’s Fig. 23B and par. 211: see 56) each include an alloy of a ferromagnetic metal and a non-magnetic metal (Saito’s par. 153: material of ferromagnetic layer include alloys CoFeB, FeB or CoB), in order to obtain the predictable result of using a known ferromagnetic alloy (Saito’s par. 153).
Regarding claims 3 and 13, Saito discloses wherein the ferromagnetic metal includes at least one of iron (Fe), cobalt (Co), or nickel (Ni) (Saito’s par. 153: Fe or Co in CoFeB, FeB or CoB), and the non-magnetic metal includes at least one of boron (B), silicon (Si), zirconium (Zr), platinum (Pt), palladium (Pd), copper (Cu), or tungsten (W) (Saito’s par. 153: B in CoFeB, FeB or CoB).
Regarding claims 4 and 14, Saito disclose wherein at least one of the non-magnetic metal layer (Saito’s Fig. 23B: see 53 shown as 13 in Fig. 1B) or the separation metal layer (Saito’s Fig. 23B: see 61) include at least one of tantalum (Ta), tungsten (W), palladium (Pd), zirconium (Zr), platinum (Pt), or ruthenium (Ru) (Saito’s par. 210, 146).
Regarding claims 5 and 15, Saito disclose wherein a thickness of each of the non-magnetic metal layer (Saito’s Fig. 23B: see 53 shown as 13 in Fig. 1B) and the separation metal layer (Saito’s Fig. 23B: see 61) is within a range of about 0.5 nm to about 3 nm (Saito’s par. 212 regarding thickness of 61 and Fig. 10 and par. 286 regarding total thickness adjusted in range from 0.5-2.5nm of non-magnetic layers in stack of 53-55 [shown as 13-15 in Fig. 1B]).
Regarding claims 10 and 20, Saito disclose wherein the free layer and the pinned layer have perpendicular magnetic anisotropies (Saito’s par. 162: recording layer and reference layer employ perpendicular magnetization).
Claims 6-7 and 16-17 are rejected under 35 U.S.C. 103 as being unpatentable over Saito in view of Lee et al. in US 2021/0367143 (hereinafter Lee).
Regarding claims 6 and 16, Saito fails to disclose wherein the magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer are inclined by 10° or more with respect to the direction parallel to the current applied to the synthetic antiferromagnet and is inclined by about 20° or more with respect to a direction perpendicular to the current applied to the synthetic antiferromagnet.
However, in the same field of endeavor of SOT-MRAM, Lee discloses:
the magnetization directions of a first ferromagnetic layer and the second ferromagnetic layer (Lee’s Fig. 2 per par. 38: directions 94 and 96 which are of ferromagnetic layers FL1 and FL2 respectively, and are equivalent to 52 and 56 respectively, in Saito’s Fig. 23B) are inclined by 10° or more with respect to the direction parallel to the current applied to the synthetic antiferromagnet (Lee’s Fig. 2 and par. 38: θ1 and θ2 are between 5°-45°, e.g. 10°) and is inclined by about 20° or more with respect to a direction perpendicular to the current applied to the synthetic antiferromagnet (Lee’s Fig. 2 and par. 38: the complement of θ1 and θ2 with respect to axis Y are between 45°-85°, e.g. 80° which is greater than 20°).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention, that Saito’s first and second ferromagnetic layers magnetization directions would meet the ranges as described, because Lee discloses a range encompassing most of the claimed range, and thus the range can be achieved through routine experimentation (see MPEP 2144.05).
Regarding claims 7 and 17, Saito fails to disclose wherein an azimuthal angle of the magnetization directions of each of the first ferromagnetic layer and the second ferromagnetic layer with respect to the direction of the current applied to the synthetic antiferromagnet is within a range of least one of about 10° to about 70°, about 110° to about 170°, about 190° to about 250°, or about 290° to about 350°.
However, in the same field of endeavor of SOT-MRAM, Lee discloses:
wherein an azimuthal angle of the magnetization directions of each of a first ferromagnetic layer and a second ferromagnetic layer with respect to the direction of the current applied to the synthetic antiferromagnet (Lee’s Fig. 2 per par. 38: see angle of 94 and 96 from +X clockwise [azimuthal from direction of current Jc]. Note that 94 and 96 are of ferromagnetic layers FL1 and FL2 respectively, and are equivalent to 52 and 56 respectively, in Saito’s Fig. 23B) is within a range of least one of about 10° to about 70°, about 110° to about 170°, about 190° to about 250°, or about 290° to about 350° (Lee’s Fig. 2 and par. 38: θ1 [azimuthal] is between 5°-45° [close to range 10°-70°], and 180+θ2 [azimuthal] is between 185°-225° [close to range 190°-250°]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention, that Saito’s first and second ferromagnetic layers magnetization directions azimuthal angles would meet the ranges as described, because Lee discloses a range encompassing most of the claimed range, and thus the range can be achieved through routine experimentation (see MPEP 2144.05).
Claims 8-9 and 18-19 are rejected under 35 U.S.C. 103 as being unpatentable over Saito in view Kishi et al. in US 2006/0082933 (hereinafter Kishi).
Regarding claims 8 and 18, Saito fails to disclose wherein the synthetic antiferromagnet further includes a third ferromagnetic layer directly on the second ferromagnetic layer, and a magnetization direction of the third ferromagnetic layer is a same direction as the magnetization direction of the second ferromagnetic layer.
However, in the related field of endeavor of magnetic elements, Kishi discloses a ferromagnetic layer comprising two layers with a same magnetization direction (Kishi’s Fig. 40 and par. 262-264: see 1b and 1c).
Therefore, it would have been obvious to one of ordinary skill in the art, that Saito’s second ferromagnetic layer (Saito’s Fig. 23B: see 56) comprises two ferromagnetic layers (as taught by Kishi), in order to obtain the benefit of preventing write errors (Kishi’s par. 258-259).
By doing such combination, Saito in view of Kishi disclose the synthetic antiferromagnet further includes a third ferromagnetic layer (Kishi’s Fig. 40 and par. 262: see 1c which upon combination corresponds to an upper layer of 56 in Saito’s Fig. 23B) directly on the second ferromagnetic layer (Kishi’s Fig. 40 and par. 262: see 1c which upon combination corresponds to a lower layer of 56 in Saito’s Fig. 23B), and a magnetization direction of the third ferromagnetic layer is a same direction as the magnetization direction of the second ferromagnetic layer (Kishi’s par. 264).
Regarding claims 9 and 19, Saito in view of Kishi disclose wherein a material of the second ferromagnetic layer and a material of the third ferromagnetic layer are different from each other (Kishi’s Fig. 40: see 1b and 1c which are two types of ferromagnetic layers per par. 257 where the two types can be achieved by different materials per par. 260).
Response to Arguments
Applicant's arguments filed 4/01/2026 have been fully considered but they are not persuasive.
On the Remarks pgs. 8-9, Applicant argues with respect to independent claims 1 and 11, that Saito’s Fig. 2A first ferromagnetic layer 12 and second ferromagnetic layer 16 have a magnetization that changes based on the direction of the current applied and therefore they are not in a stable state.
The office must respectfully disagree, as explained in the rejection above, Saito discloses achieving stable magnetization switching (Saito’s par. 237-238) and DM interaction (Saito’s par. 214). This is consistent with the instant disclosure (pg. pub. par. 56) where:
[0046] In addition, an arrangement of magnetization states of the first ferromagnetic layer 111 and the second ferromagnetic layer 113 may be determined as a stable state by the Dzyaloshinskii-Moriya interaction occurring on the interface between the non-magnetic metal layer 112 and the first ferromagnetic layer 111 and on the interface between the non-magnetic metal layer 112 and the second ferromagnetic layer 113.
Conclusion
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/LILIANA CERULLO/Primary Examiner, Art Unit 2621
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