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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 11/12/2025 has been entered.
Claim Rejections - 35 USC § 112
Claims 23, 25-29 and 30-33 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 23 recites the limitation "the first layer" in the 15 line of the claim. There is insufficient antecedent basis for this limitation in the claim.
Claim 23 recites the limitation "the second layer" in the 19th line of the claim. There is insufficient antecedent basis for this limitation in the claim.
Claim 30 recites the limitation "the first layer" in the 15th line of the claim. There is insufficient antecedent basis for this limitation in the claim.
Claim 30 recites the limitation "the second layer" in the 19th line of the claim. There is insufficient antecedent basis for this limitation in the claim.
Claims 25-29 and 31-33 are rejected because they depend on the rejected claims 23 and 30.
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 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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1-4 and 6-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2014/0145792) in view of Hu (US 2017/0229642), and further in view of Whig et al. (US 2012/0313191).
Regarding claim 1, Wang et al. teach a magnetoresistive device (MTJ Stack; Fig. 3, [0020]), comprising: a tunnel barrier region (29; Fig. 3, [0030]); a magnetically fixed region (SAF reference layer 20; Fig. 3, [0038]) positioned on one side (the bottom side) of the tunnel barrier region (29); a magnetically free region (SAF free layer 30; Fig. 3, [0038]) positioned on a side (the top side) of the tunnel barrier region (29) opposite to the one side (the bottom side of 29), wherein the magnetically free region (30) includes at least (a) a first ferromagnetic region (32/FL1; Fig. 3, [0031]), (b) a second ferromagnetic region (34/FL2; Fig. 3, [0031]), and (c) a nonmagnetic insertion region (coupling layer 33 which can be Ru; Fig. 3, [0035]) position between the first and second ferromagnetic regions (32/FL1, 34/FL2), wherein the first ferromagnetic region (32/FL1) is in contact with the nonmagnetic insertion region (33) and the second ferromagnetic region (34/FL2) is in contact with the nonmagnetic insertion region (33) opposite the first ferromagnetic region (32/FL1; see Fig. 3); and wherein the second ferromagnetic region (34/FL2) includes a multi-layer structure ((Co/Pd)n of FL2; Fig. 3, [0036, 0032]) comprising: a first set of one or more layers (the first ten Co layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0032]), each layer in the first set (the first ten Co layers of (Co/Pd)n of FL2 with n=10) formed from a first material (Co; [0032]) comprising cobalt ([0032]); and a second set of one or more layers (the first nine Pd layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0032]), each layer in the second set (the first nine Pd layers of (Co/Pd)n of FL2 with n=10) formed from a second material (Pd) comprising at least one of platinum or palladium (Pd; [0032]), wherein a total number of layers of the first and second sets of layers (the first ten Co layers of (Co/Pd)n of FL2 with n=10 and the first nine Pd layers of (Co/Pd)n of FL2 with n=10) in the multi-layer structure ((Co/Pd)n of FL2) of the second ferromagnetic region (34/FL2) equals an odd number (19); and the first ferromagnetic region (32/FL1) includes a multi-layer structure (32/FL1) comprising: a boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprising boron ([0032]), and a boron-free ferromagnetic layer (32; [0036]) comprising an alloy consisting of cobalt and iron (32 is made of Co, Fe, Ni, or an alloy thereof disclosed in [0036], it would have been obvious to one of ordinary skill in the art to know that “an alloy thereof” indicates an alloy of CoFe, CoNi, FeNi or CoFeNi; and CoFe is the alloy consisting of cobalt and iron), wherein the boron-free ferromagnetic layer (CoFe of 32) comprises cobalt ([0036]) with a remainder (one of the remaining elements) being iron (Fe; [0036]), wherein the boron-rich ferromagnetic layer (CoFeB of FL1) contacts the boron-free ferromagnetic layer (CoFe of 32; see Fig. 3).
Wang et al. do not teach an iron rich region, consisting essentially of iron, at an interface of the first ferromagnetic region with the tunnel barrier region, a boron-rich ferromagnetic layer comprising approximately 40 to 60 atomic percent of boron (emphasis added), the boron-free ferromagnetic layer (CoFe of 32) comprises approximately 25 to 75 atomic percent cobalt (emphasis added), the boron-rich ferromagnetic layer contacts the iron rich region.
Regarding the limitation “the boron-free ferromagnetic layer comprises approximately 25 to 75 atomic percent cobalt”, parameters such as the atomic percent cobalt of CoFe in the art of semiconductor manufacturing process are subject to routine experimentation and optimization to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.). Therefore, it would have been obvious to one of the ordinary skill in the art at the time the invention was made to incorporate the atomic percent cobalt of CoFe within the range as claimed in order to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.)
In the same field of endeavor of magnetoresistive stack, Hu teaches a boron-rich ferromagnetic layer (CoFeB in the free layer 25; [0044]) comprising 15 to 60 atomic percent of boron which overlaps the claimed range of approximately 40 to 60 atomic percent of boron, that establishes a prima facie case of obviousness (MPEP 2144.05).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Hu and to use the atomic percent of boron as taught by Hu ([0044]), because Wang et al. teach a boron-rich ferromagnetic layer of CoFeB in the free layer ([0032]), but is silent about the atomic percent of boron of the CoFeB, while Hu teach that the CoFeB in the free layer can have 15 to 60 atomic percent of boron ([0044]).
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach an iron rich region (302; Fig. 3, [0052]), consisting essentially of iron (a continuous atomic layer of Fe, [0052]), at an interface (302; Fig. 3, [0038]) of the first ferromagnetic region (202 of high-B CoFeB; Fig. 3, [0052]) with the tunnel barrier region (208; Fig. 3, [0037]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include an iron rich region at an interface of the first ferromagnetic region with the tunnel barrier region as taught by Whig et al., because an iron rich region can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
The combination of Wang et al. and Whig et al. teach “the boron-rich ferromagnetic layer contacts the iron rich region” because Whig teaches the ion rich region (302; Fig. 3, [0038]) at an interface of the first ferromagnetic region (202 of high-B CoFeB; Fig. 3, [0052]) with the tunnel barrier region (208; Fig. 3, [0037]) which corresponds to the ion rich region at an interface of the first ferromagnetic region (32/FL1) with the tunnel barrier region (29) in Fig. 3 of Wang et al. Thus, the ion rich region at the interface of 32/FL1 with 29 would contact the boron-rich ferromagnetic layer (CoFeB of FL1) in Fig. 3 of Wang et al.
Regarding claim 2, Wang et al. teach the magnetoresistive device of claim 1, wherein the nonmagnetic insertion region (33) includes at least one of tantalum, tungsten, molybdenum, ruthenium, rhodium, rhenium, iridium, chromium, hafnium, zirconium, or osmium (Ru, ruthenium; [0035]).
Regarding claim 3, Wang et al. teach the magnetoresistive device of claim 1, wherein each layer of the multi-layer structure ((Co/Pd)n) of the second ferromagnetic region (34/FL2) includes a thickness between 0.5 and 5 Å or between 2 and 10 Å ([0032]) which overlaps the claimed range of between about 1-6 Å that establishes a prima facie case of obviousness (MPEP 2144.05).
Regarding claim 4, Wang et al. teach the magnetoresistive device of claim 1, wherein the boron-rich ferromagnetic layer (CoFeB of FL1) includes an alloy of cobalt, iron, and boron ([0032]).
Regarding claim 6, Wang et al. teach the magnetoresistive device of claim 1, wherein the boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprised boron.
Wang et al. do not teach the boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprising approximately 45 to 55 atomic percent of boron (emphasis added).
In the same field of endeavor of magnetoresistive stack, Hu teaches the boron-rich ferromagnetic layer (CoFeB in the free layer 25; [0044]) comprising 15 to 60 atomic percent of boron which overlaps the claimed range of approximately 45 to 55 atomic percent of boron, that establishes a prima facie case of obviousness (MPEP 2144.05).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Hu and to use the atomic percent of boron as taught by Hu ([0044]), because Wang et al. teach a boron-rich ferromagnetic layer of CoFeB in the free layer ([0032]), but is silent about the atomic percent of boron of the CoFeB, while Hu teach that the CoFeB in the free layer can have 15 to 60 atomic percent of boron ([0044]).
Regarding claim 7, Wang et al. teach wherein the tunnel barrier region (29) is a first tunnel barrier region (29) and the magnetically fixed region (20) is a first magnetically fixed region (20), and wherein the magnetoresistive device (MTJ stack) further comprises.
Wang et al. do not teach a second tunnel barrier region positioned on a side of the magnetically free region opposite the first tunnel barrier region; and a second magnetically fixed region positioned on a side of the second tunnel barrier region opposite the magnetically free region.
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach a second tunnel barrier region (208; Fig. 2, [0037]) positioned on a side (the top side) of the magnetically free region (202; Fig. 2, [0037]) opposite the first tunnel barrier region (210; Fig. 2, [0037]); and a second magnetically fixed region (232; Fig. 2, [0038]) positioned on a side (the top side) of the second tunnel barrier region (208) opposite the magnetically free region (202; see Fig. 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Whig et al. and to incorporate a second tunnel barrier region and a second magnetically fixed region as taught by Whig et al., because they can be used to form a dual spin-filter MJT as taught by Whig et al. ([0037]).
Regarding claim 8, Wang et al. teach the magnetoresistive device of claim 1, wherein the multi-layer structure ((Co/Pd)n) of the second ferromagnetic region (34/FL2) includes at least two layers comprising cobalt separated by a layer of platinum or palladium (n can be between 1 and 10; [0032]).
Regarding claim 9, Wang et al. teach the magnetoresistive device of claim 1, wherein the multi-layer structure ((Co/Pd)n) of the second ferromagnetic region (34/FL2) includes at least five layers comprising cobalt (n can be between 1 and 10; [0032]).
Regarding claim 10, Wang et al. teach the magnetoresistive device of claim 1, wherein the tunnel barrier region (29) includes one of magnesium oxide and aluminum oxide (MgO; [0030]).
Claim(s) 22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al., Hu and Whig et al. as applied to claim 1 above, and further in view of Brown et al. (US 2017/0110506).
Regarding claim 22, Wang et al. teach wherein at least one layer in the second set of one or more layers (one layer of the Pd layers of (Co/Pd)n of FL2) of the second ferromagnetic region (34/FL2).
Wang et al. do not teach at least one layer in the second set of one or more layers includes an alloy comprising platinum and iron.
In the same field of endeavor of magnetic memory devices, Brown et al. teach at least one layer in the second set of one or more layers (the FePt layer; [0026]) includes an alloy comprising platinum and iron ([0026]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Brown et al., and to substitute the second layer with a layer of FePt, because Wang et al. teach that the second layer (Pd layer) is the second layer of the (Co/Pd)n layer, while the (Co/Pd)n layer can be substituted by a laminated stack exhibiting PMA ([0032]), but Wang et al. is silent about the actual material of the PMA stack, and Brown et al. teach that the laminated stack exhibiting PMA can be a multilayer structure made of alternating layers of Co and FePt, the FePt being an alloy having strong PMA, with the second layer being FePt ([0026]).
Claim(s) 23, 25-29 and 32-33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2014/0145792) in view of Hu (US 2017/0229642), Whig et al. (US 2012/0313191), and further in view of Brown et al. (US 2017/0110506).
Regarding claim 23, Wang et al. teach a magnetoresistive device (MTJ Stack; Fig. 3, [0020]), comprising: a magnetically fixed region (SAF reference layer 20; Fig. 3, [0038]); a magnetically free region (SAF free layer 30; Fig. 3, [0038]) comprising: a first set of one or more layers (34 of Co and the ten Co layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0036, 0032]), each layer in the first set (34 of Co and the ten Co layers of (Co/Pd)10 of FL2) formed form a first material (Co; 34 of Co and the ten Co layers of (Co/Pd)10 of FL2) comprising cobalt ([0036, 0032]); a second set of one or more layers (the ten Pd layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0032]), each layer in the second set (the ten Pd layers of (Co/Pd)10 of FL2; Fig. 3, [0032]) formed from a second material (Pd), wherein a total number of layers of the first and second sets of layers (one layer of 34 and twenty layers of (Co/Pd)10 of FL2) equals an odd number (21); a boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprising boron; a boron-free ferromagnetic layer (32; [0036]) comprising an alloy consisting of cobalt and iron (32 is made of Co, Fe, Ni, or an alloy thereof disclosed in [0036], it would have been obvious to one of ordinary skill in the art to know that “an alloy thereof” indicates an alloy of CoFe, CoNi, FeNi or CoFeNi; and CoFe is the alloy consisting of cobalt and iron), wherein the boron-free ferromagnetic layer (CoFe of 32) comprises cobalt ([0036]) with a remainder (one of the remaining elements) being iron (Fe; [0036]); and a nonmagnetic insertion region (coupling layer 33 which can be Ru; Fig. 3, [0035]) positioned between the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) and the boron-rich ferromagnetic layer (CoFeB of FL1), wherein the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) is in contact with the nonmagnetic insertion region (33) and the boron-free ferromagnetic layer (CoFe of 32) is in contact with the nonmagnetic insertion region (33) opposite the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10), wherein the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) is between the nonmagnetic insertion region (33) and the second layer (the bottommost layer of Pd of (Co/Pd)n of 34/FL2 with n=10), wherein the second layer (the bottommost layer of Pd of (Co/Pd)n of 34/FL2 with n=10) is in contact with a third layer (the second bottommost of Co of (Co/Pd)n of 34/FL2 with n=10) having a same composition (Co) as the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10 of Co) opposite (different position from) the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10 of Co); and a tunnel barrier region (29; Fig. 3, [0030]) between the magnetically fixed region (20) and the magnetically free region (30), wherein the boron-rich ferromagnetic layer (CoFeB of FL1) contacts the boron-free ferromagnetic layer (32).
Wang et al. do not teach a second material comprising an alloy comprising platinum and iron, a boron-rich ferromagnetic layer comprising approximately 40 to 60 atomic percent boron (emphasis added), the boron-free ferromagnetic layer comprises approximately 25 to 75 atomic percent cobalt (emphasis added), an iron rich region, consisting essentially of iron, the boron-rich ferromagnetic layer contacts the iron rich region, and wherein the iron rich region is located at an interface between the boron-rich ferromagnetic layer and the tunnel barrier region.
Regarding the limitation “the boron-free ferromagnetic layer comprises approximately 25 to 75 atomic percent cobalt”, parameters such as the atomic percent cobalt of CoFe in the art of semiconductor manufacturing process are subject to routine experimentation and optimization to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.). Therefore, it would have been obvious to one of the ordinary skill in the art at the time the invention was made to incorporate the atomic percent cobalt of CoFe within the range as claimed in order to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.)
In the same field of endeavor of magnetoresistive stack, Hu teaches a boron-rich ferromagnetic layer (CoFeB in the free layer 25; [0044]) comprising 15 to 60 atomic percent of boron which overlaps the claimed range of approximately 40 to 60 atomic percent boron, that establishes a prima facie case of obviousness (MPEP 2144.05).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Hu and to use the atomic percent of boron as taught by Hu ([0044]), because Wang et al. teach a boron-rich ferromagnetic layer of CoFeB in the free layer ([0032]), but is silent about the atomic percent of boron of the CoFeB, while Hu teach that the CoFeB in the free layer can have 15 to 60 atomic percent of boron ([0044]).
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach an iron rich region (302; Fig. 3, [0052]), consisting essentially of iron (a continuous atomic layer of Fe, [0052]), the boron-rich ferromagnetic layer (202 of high-B CoFeB; Fig. 3, [0052]) contacts the iron rich region (302; Fig. 3), and wherein the iron rich region (302) is located at an interface (302; Fig. 3, [0038]) between the boron-rich ferromagnetic layer (202) and the tunnel barrier region (208; Fig. 3, [0037]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include an iron rich region as taught by Whig et al., because an iron rich region can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
In the same field of endeavor of magnetic memory devices, Brown et al. teach a second material (the FePt layer; [0026]) comprising an alloy comprising platinum and iron ([0026]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Brown et al., and to substitute the second layer with a layer of FePt, because Wang et al. teach that the second layer (Pd layer) is the second layer of the (Co/Pd)n layer, while the (Co/Pd)n layer can be substituted by a laminated stack exhibiting PMA ([0032]), but Wang et al. is silent about the actual material of the PMA stack, and Brown et al. teach that the laminated stack exhibiting PMA can be a multilayer structure made of alternating layers of Co and FePt, the FePt being an alloy having strong PMA, with the second layer being FePt ([0026]).
Regarding claim 25, Wang et al. teach the magnetoresistive device of claim 23, wherein the nonmagnetic insertion region (33) includes at least one of tantalum, tungsten, molybdenum, ruthenium, rhodium, rhenium, iridium, chromium, hafnium, zirconium, or osmium (Ru, ruthenium; [0035]).
Regarding claim 26, Wang et al. teach the magnetoresistive device of claim 23, wherein the tunnel barrier region (29) is a first tunnel barrier region (29) and the magnetically fixed region (20) is a first magnetically fixed region (20), and wherein the magnetoresistive device (MTJ stack) further comprises.
Wang et al. do not teach a second tunnel barrier region positioned on a side of the magnetically free region opposite the first tunnel barrier region; and a second magnetically fixed region positioned on a side of the second tunnel barrier region opposite the magnetically free region.
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach a second tunnel barrier region (210; Fig. 2, [0037]) positioned on a side (the bottom side) of the magnetically free region (202; Fig. 2, [0037]) opposite the first tunnel barrier region (208; Fig. 2, [0037]); and a second magnetically fixed region (220; Fig. 2, [0038]) positioned on a side (the bottom side) of the second tunnel barrier region (210) opposite the magnetically free region (202; see Fig. 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Whig et al. and to incorporate a second tunnel barrier region and a second magnetically fixed region as taught by Whig et al., because they can be used to form a dual spin-filter MJT as taught by Whig et al. ([0037]).
Regarding claim 27, Wang et al. teach the magnetoresistive device of claim 26.
Wang et al. do not teach wherein the iron rich region is a first iron rich region, and the magnetoresistive device further includes a second iron rich region.
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach wherein the iron rich region (302; Fig. 3, [0052]) is a first iron rich region (302; Fig. 8, [0058]), and the magnetoresistive device (MRAM; [0001]) further includes a second iron rich region (818; Fig. 8, [0058]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include the first and the second iron rich regions as taught by Whig et al., because the ion rich regions can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
Regarding claim 28, Wang et al. teach the magnetoresistive device of claim 27, wherein the magnetically free region (30) and the first tunnel barrier region (29).
Wang et al. do not teach wherein the first iron rich region is disposed between the magnetically free region and the first tunnel barrier region, and the second iron rich region is disposed between the magnetically free region and the second tunnel barrier region.
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach wherein the first iron rich region (320) is disposed between the magnetically free region (802/202; Fig. 8, [0058]) and the first tunnel barrier region (208; see Fig. 3, [0058]), and the second iron rich region (818) is disposed between the magnetically free region (802/202) and the second tunnel barrier region (210; Fig. 8, [0058]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include the first and the second iron rich regions as taught by Whig et al., because the ion rich regions can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
Regarding claim 29, Wang et al. teach the magnetoresistive device of claim 23, wherein the boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprised boron; and the boron-free ferromagnetic layer (CoFe of 32) comprises cobalt with a remainder (one of the remaining elements) being iron (Fe; [0036]).
Wang et al. do not teach the boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprising approximately 45 to 55 atomic percent boron; and the boron-free ferromagnetic layer (CoFe of 32) comprises approximately 25 to 75 atomic percent cobalt (emphasis added).
In the same field of endeavor of magnetoresistive stack, Hu teaches the boron-rich ferromagnetic layer (CoFeB in the free layer 25; [0044]) comprising 15 to 60 atomic percent of boron which overlaps the claimed range of approximately 45 to 55 atomic percent boron, that establishes a prima facie case of obviousness (MPEP 2144.05).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Hu and to use the atomic percent of boron as taught by Hu ([0044]), because Wang et al. teach a boron-rich ferromagnetic layer of CoFeB in the free layer ([0032]), but is silent about the atomic percent of boron of the CoFeB, while Hu teach that the CoFeB in the free layer can have 15 to 60 atomic percent of boron ([0044]).
Parameters such as the atomic percent cobalt of CoFe in the art of semiconductor manufacturing process are subject to routine experimentation and optimization to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036]). Therefore, it would have been obvious to one of the ordinary skill in the art at the time the invention was made to incorporate the atomic percent cobalt of CoFe within the range as claimed in order to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036]).
Regarding claim 32, Wang et al. teach the magnetoresistive device of claim 23, wherein the tunnel barrier region (29) is above and in contact with the magnetically fixed region (20), and the magnetically free region (30) is above the tunnel barrier region (29; see Fig. 3).
Regarding claim 33, Wang et al. teach the magnetoresistive device of claim 32, wherein: the second layer (the bottommost layer of Pd of (Co/Pd)n of 34/FL2 with n=10) is above and in contact with the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10); the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) is above and in contact with the nonmagnetic insertion region (33; see Fig. 3); the nonmagnetic insertion region (33) is above and contact with the boron-free ferromagnetic layer (CoFe of 32; see Fig. 3); the boron-free ferromagnetic layer (CoFe of 32) is above and in contact with the boron-rich ferromagnetic layer (CoFeB of FL1).
Wang et al. do not teach the iron rich region is between the magnetically free region and the tunnel barrier region.
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach the iron rich region (302; Fig. 3, [0052]) is between the magnetically free region (the free magnetic layer 202; Fig. 3, [0052]) and the tunnel barrier region (208; Fig. 3, [0037]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include an iron rich region as taught by Whig et al., because an iron rich region can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
Claim(s) 30-31 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2014/0145792) in view of Hu (US 2017/0229642), and further in view of Whig et al. (US 2012/0313191) and Brown et al. (US 20170110506).
Regarding claim 30, Wang et al. teach a magnetoresistive device (MTJ Stack; Fig. 3, [0020]), comprising: a magnetically fixed region (SAF reference layer 20; Fig. 3, [0038]); a magnetically free region (SAF free layer 30; Fig. 3, [0038]) comprising: a first set of one or more layers (34 of Co and the ten Co layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0036, 0032]), each layer in the first set (34 of Co and the ten Co layers of (Co/Pd)10 of FL2) formed from a first material (Co; 34 of Co and the ten Co layers of (Co/Pd)10 of FL2) comprising cobalt ([0036, 0032]); a second set of one or more layers (the ten Pd layers of (Co/Pd)n of FL2 with n=10; Fig. 3, [0032]), each layer in the second set (the ten Pd layers of (Co/Pd)10 of FL2; Fig. 3, [0032]) formed from a second material (Pd), wherein a total number of layers of the first and second sets of layers (one layer of 34 and twenty layers of (Co/Pd)10 of FL2) equals an odd number (21); a boron-rich ferromagnetic layer (CoFeB of FL1; [0032]) comprising boron ([0032]); a boron-free ferromagnetic layer (32; [0036]) comprising an alloy that consists of cobalt and iron (32 is made of Co, Fe, Ni, or an alloy thereof disclosed in [0036], it would have been obvious to one of ordinary skill in the art to know that “an alloy thereof” indicates an alloy of CoFe, CoNi, FeNi or CoFeNi; and CoFe is the alloy consisting of cobalt and iron), wherein the boron-free ferromagnetic layer (CoFe of 32) comprises cobalt ([0036]) with a remainder (one of the remaining elements) being iron (Fe; [0036]); and a nonmagnetic insertion region (coupling layer 33 which can be Ru; Fig. 3, [0035]) positioned between the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) and the boron-rich ferromagnetic layer (CoFeB of FL1), wherein the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) is in contact with the nonmagnetic insertion region (33; see Fig. 3) and the boron-free ferromagnetic layer (32) is in contact with the nonmagnetic insertion region (33) opposite the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10), wherein the first layer (34 of Co and the bottommost layer of Co of (Co/Pd)n of 34/FL2 with n=10) is between the nonmagnetic insertion region (33) and the second layer (the bottommost layer Pd of (Co/Pd)n of 34/FL2 with n=10); and a tunnel barrier region (29; Fig. 3, [0030]) between the magnetically fixed region (20) and the magnetically free region (30).
Wang et al. do not teach a second material comprising an alloy comprising platinum and iron, a boron-rich ferromagnetic layer comprising approximately 40 to 60 atomic percent boron (emphasis added), the boron-free ferromagnetic layer comprises approximately 25 to 75 atomic percent cobalt (emphasis added), an iron rich region, consisting essentially of iron, wherein the boron-rich ferromagnetic layer is between the boron-free ferromagnetic layer and the iron rich region, and wherein the iron rich region is in contact with the tunnel barrier region.
Regarding the limitation “the boron-free ferromagnetic layer comprises approximately 25 to 75 atomic percent cobalt”, parameters such as the atomic percent cobalt of CoFe in the art of semiconductor manufacturing process are subject to routine experimentation and optimization to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.). Therefore, it would have been obvious to one of the ordinary skill in the art at the time the invention was made to incorporate the atomic percent cobalt of CoFe within the range as claimed in order to achieve the desired enhancement of the RKKY coupling strength during device fabrication ([0036] of Wang et al.)
In the same field of endeavor of magnetoresistive stack, Hu teaches a boron-rich ferromagnetic layer (CoFeB in the free layer 25; [0044]) comprising 15 to 60 atomic percent of boron which overlaps the claimed range of approximately 40 to 60 atomic percent boron, that establishes a prima facie case of obviousness (MPEP 2144.05).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Hu and to use the atomic percent of boron as taught by Hu ([0044]), because Wang et al. teach a boron-rich ferromagnetic layer of CoFeB in the free layer ([0032]), but is silent about the atomic percent of boron of the CoFeB, while Hu teach that the CoFeB in the free layer can have 15 to 60 atomic percent of boron ([0044]).
In the same field of endeavor of semiconductor manufacturing, Whig et al. teach an iron rich region (302; Fig. 3, [0052]), consisting essentially of iron (a continuous atomic layer of Fe, [0052]), and wherein the iron rich region (302) is in contact with the tunnel barrier region (208; Fig. 3, [0037]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al., Hu and Whig et al., and to include an iron rich region as taught by Whig et al., because an iron rich region can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
The combination of Wang et al. and Whig et al. teach “wherein the boron-rich ferromagnetic layer is between the boron-free ferromagnetic layer and the iron rich region” because Whig teaches the ion rich region (302) at an interface of the magnetically free region (the free magnetic layer 202; Fig. 3, [0052]) with the tunnel barrier region (208; Fig. 3, [0037]) which corresponds to the ion rich region at an interface of the magnetically free region (30) with the tunnel barrier region (29) in Fig. 3 of Wang et al. Thus, in Fig. 3 of Wang, the boron-rich ferromagnetic layer (CoFeB of FL1) is between the boron-free ferromagnetic layer (CoFe of 32) and the iron rich region (at the interface of 30 and 29).
Wang et al. do not teach a second material comprising an alloy comprising platinum and iron.
In the same field of endeavor of magnetic memory devices, Brown et al. teach a second material (the material of the FePt layer; [0026]) comprising an alloy comprising platinum and iron (FePt; [0026])
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Brown et al., and to substitute the second layer with a layer of FePt, because Wang et al. teach that the second layer (Pd layer) is the second layer of the (Co/Pd)n layer, while the (Co/Pd)n layer can be substituted by a laminated stack exhibiting PMA ([0032]), but Wang et al. is silent about the actual material of the PMA stack, and Brown et al. teach that the laminated stack exhibiting PMA can be a multilayer structure made of alternating layers of Co and FePt, the FePt being an alloy having strong PMA, with the second layer being FePt ([0026]).
Regarding claim 31, Wang et al. teach the magnetoresistive device of claim 30.
Wang et al. do not teach wherein the iron rich region has a thickness of approximately 1 Å to approximately 3 Å.
In the same field of endeavor of magnetic memory devices, Whig et al. teach wherein the iron rich region (302) has a thickness of approximately 1 Å to approximately 3 Å (1.5 Å - 3Å; [0052]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the inventions of Wang et al. and Whig et al., and to include an iron rich region as taught by Whig et al., because an iron rich region can obtain higher MR values and provide higher perpendicular interface anisotropy energy as taught by Whig et al. ([0052]).
Response to Arguments
Applicant’s amendments, filed 11/12/2025, overcome the rejections to claims 1-4, 6-10 and 22 under 35 U.S.C. 112. The rejections to claims 1-4, 6-10 and 22 under 35 U.S.C. 112 have been withdrawn.
Applicant's arguments with respect to claims 23 and 30 have been considered but are moot in view of the new ground(s) of rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Deshpande et al. (US 12369495 B2) teach a magnetoresistive stack/structure having a tunnel barrier between two magnetic regions.
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/HSIN YI HSIEH/Primary Examiner, Art Unit 2899 12/27/2025