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 .
Status of Claims
The current application contains device and method claims that are commonly subjected to restrictions. However, since method claims do not contain any specific feature related to a process, the current Office Action will examine both – device and method claims: Claims 1-20 are examined on merits herein.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “topological insulator”, cited by Claim 8, must be shown or the feature canceled from the claim. No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Specification
The specification is objected to as failing to provide proper antecedent basis for the claimed subject matter. See 37 CFR 1.75(d)(1) and MPEP § 608.01(o). Correction of the following is required: Claim 9 recites: “the SOT layer structure further includes a topological insulator layer”, which is not supported by the specification of the application, teaching (paragraph 0015 of the published application, US 2024/0155949) that a topological insulator layer is provided between the SOT layer structure and the free layer, while paragraph 0040 of the published application teaches that the topological insulator layer may be used instead of the heavy metal layer.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claim 8 is rejected under 35 U.S.C. 112(b) 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.
In re Claim 8: Claim 8 recites: “the SOT layer structure further includes a topological insulator layer”. The recitation is unclear, since it is not supported by the specification of the application, teaching (paragraph 0015 of the published application) that a topological insulator layer is provided between the SOT layer structure and the free layer and also teaching (paragraph 0040 of the published application) that a topological insulator layer may be used instead of the heavy metal layer.
Appropriate correction is required to clarify the claim language.
For this Office Action, Claim 8 was interpreted as filed (assuming that Applicant will provide a correlation between Claim 8 and the specification).
Claim Rejections - 35 USC § 103
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 1-4, 7, 9-13, 15-16, and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Guo et al. (US 2021/0328134).
In re Claim 1, Guo teaches a magnetic tunnel junction (MTJ) device, comprising (Fig. 1; see also Figs. 4-6):
an MTJ element 14/13/12 including a magnetic reference layer 14 (paragraph 0030), a magnetic free layer 12 (called “magnetic memory layer” paragraph 0020, but could be identified as “magnetic free” – as in the current application, due to its ability to change magnetization, paragraphs 0030-0031), and a non-magnetic barrier layer 13 (paragraph 0024) separating the magnetic reference layer 14 and the magnetic free layer 12; and
a spin-orbit torque (SOT) layer structure 11/10 (paragraph 0020-0022) arranged below the MTJ element 14/13/12 and configured to provide a write current for switching a magnetization direction of the magnetic free layer through SOT (paragraph 0009, Fig. 5A and paragraph 0030 as directed to influence of magnetic layer 10 on magnetic-free layer 12, and Figs. 6A-6C paragraph 0031 directed to writing); wherein
the SOT layer structure comprises a heavy metal layer 11 (called SHC layer, paragraph 0020, but could be called “heavy metal layer”, as in the current application, comparing its materials in paragraph 0022 with Periodic Table – attached to this Office Action) and a magnetic layer 10 (paragraph 0021); and wherein
the magnetic layer 10 is arranged below the heavy metal layer 11 and configured to induce a magnetic field in the magnetic free layer 12 (paragraphs 0009 and 0030), thereby promoting magnetic switching of the magnetization of the magnetic free layer 12 (paragraph 0031).
Although Guo does not use a combination of words: “deterministic switching”, but refers only to “magnetic switching”, the procedure described by Guo is described in some art as “deterministic switching” – see Fig. 1A and paragraph 0049 of Sun, US 2019/0312198, on a common knowledge in the art, to support the statement. Therefore, it would have been obvious for one of ordinary skill in the art before filing the application to have had the “magnetic switching” be “deterministic switching”.
In re Claim 2, Guo teaches the MTJ device according to Claim 1, wherein the magnetic layer 10 (Fig. 1, paragraph 0021) includes a material selected from the group consisting of Fe, Co, Ni, FeCo, FeCoB, NiFe, NdFeB, WCoFeB, and TaCoFeB – Guo explicitly teaches Fe, Co, Ni, and NiFe.
In re Claim 3, Guo teaches the MTJ device according to Claim 1, wherein the magnetic layer 10 (Fig. 1) has an average thickness in the range of 2-5 nm – Guo teaches a thickness in a range from 1.5 nm to 10 nm (paragraph 0021). Note that in accordance with MPEP 2144.05 Obviousness of Similar and Overlapping Ranges, Amounts, and Proportions. I. OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
In re Claim 4, Guo teaches the MTJ device according to Claim 1, wherein (Figs. 6A-6B, paragraph) the magnetic layer 10 is formed on a bottom electrode BE1, BE2 (paragraphs 0011, 0031) of the MTJ device.
In re Claim 7, Guo teaches the MTJ device according to Claim 1 as cited above, wherein the heavy metal layer 11 (Fig. 1) includes a material selected from the group consisting of W, Ta, Pt, Cu, PtMn, PtCu, and PtCr – from the claimed materials, Guo explicitly teaches Pt and Cu (paragraph 0022).
In re Claim 9, Guo teaches the MTJ device according to Claim 1 as cited above and wherein the heavy metal layer 11 (Fig. 1) has an average thickness in the range of 2-6 nm – Guo teaches a thickness in a range from 1.5 nm to 10 nm (paragraph 0022), which encompasses the claimed thickness. Note that in accordance with MPEP 2144.05 Obviousness of Similar and Overlapping Ranges, Amounts, and Proportions. I. OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
In re Claim 10, Guo teaches the MTJ device according to Claim 1 as cited above, wherein (Figs. 1, 4, 6) the heavy metal layer 11 has a shape corresponding to a shape of the magnetic layer 10 (paragraph 0021).
In re Claim 11, Guo teaches the MTJ device according to Claim 1, wherein the MTJ element is a top-pinned element, e.g., its magnetic reference layer 14 (Fig. 1) is over the magnetic-free layer 12.
In re Claim 12, Guo teaches the MTJ device according to Claim 1 as cited above, wherein (Figs. 1 and 6) the magnetic free layer 12 is formed on the SOT layer structure 11/10.
In re Claim 13, Guo teaches the MTJ device according to Claim 1 as cited above, wherein the magnetic free layer 12 (Figs. 1, 6) is formed of a single CoFeB layer or a synthetic-antiferromagnetic hybrid-free layer – Gou teaches a single layer of CoFeB (paragraph 0023).
In re Claim 15, Guo teaches a method of fabricating a magnetic tunnel junction (MTJ) device (obviously, since Guo creates the device) comprising (Figs. 1 and 6):
providing (obviously) an MTJ element 14/13/12 including a magnetic reference layer 14 (paragraph 0030), a magnetic free layer 12 (called “magnetic memory layer”, paragraph 0020, but could be identified as “magnetic free” – as in the current application, since its magnetization is not constant but can be changed, paragraphs 0030-0031), and a non-magnetic barrier layer 13 (paragraph 0024) separating the magnetic reference layer 14 and the magnetic free layer 12; and
providing (obviously) a spin-orbit torque (SOT) layer structure 11/12 (paragraphs 0020-0022) arranged below the MTJ element 14/13/12 and configured to provide a write current for switching a magnetization direction of the magnetic free layer through SOT (paragraph 0009, Fig. 5 and paragraph 0030 on influence of magnetic layer 10 on magnetic-free-layer 12 and Figs. 6A-6C, paragraph 0031, directed to writing and a writing current); wherein
the SOT layer structure 11/10 comprises a heavy metal layer 11 (called SHL layer in paragraph 0020, but it could be called “a heavy metal layer”, as in the current application, comparing its materials in paragraph 0022 with Periodic Table) and a magnetic layer 10 (paragraph 0021); and wherein
the magnetic layer 10 is arranged below the heavy metal layer 11 and configured to induce a magnetic field in the magnetic free layer in a direction of the write current through the SOT layer structure (paragraphs 0009, 0030), thereby promoting magnetic switching of the magnetization of the magnetic free layer 12.
Although Guo does not use a combination of words: “deterministic switching”, but refers only to “magnetic switching”, the procedure described by Guo is described in some art as “deterministic switching” – see Fig. 1A and paragraph 0049 of Sun, US 2019/0312198, on a common knowledge in the art, to support the statement. Therefore, it would have been obvious for one of ordinary skill in the art before filing the application to have the “magnetic switching” be “deterministic switching”.
In re Claim 16, Guo teaches the method according to Claim 15 as cited above, wherein the magnetic layer 10 (Figs. 1, 6) has an average thickness in the range of 2-5 nm - Guo teaches a thickness in a range from 1.5 nm to 10 nm (paragraph 0021) which overlaps the claimed range: In accordance with MPEP 2144.05 Obviousness of Similar and Overlapping Ranges, Amounts, and Proportions. I. OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
In re Claim 19, Guo teaches the method according to Claim 15 as cited above and wherein the heavy metal layer 11 (Figs. 1, 6) has an average thickness in the range of 2-6 nm – Guo teaches a range for the thickness in a range from 1.5 nm to 10 nm (paragraph 0022), and in accordance with MPEP 2144.05 Obviousness of Similar and Overlapping Ranges, Amounts, and Proportions. I. OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
In re Claim 20, Guo teaches the method according to Claim 15 as cited above, wherein (Figs. 1, 4, 6) the heavy metal layer 11 has a shape corresponding to a shape of the magnetic layer 10 (paragraph 0021).
As far as Claim 8 is understood, Claims 5-6, 8, and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Guo in view of Garello et al. (US 2020/0203598).
In re Claims 5 and 17, Guo teaches the MTJ device according to Claim 1 and a method of manufacturing the MTJ device of Claim 15 as cited above, where the write current passes through the heavy metal layer 11 (Fig. 6, paragraphs 0030-0031). Guo further teaches (Fig. 3, paragraphs 0028-0029) that a portion of a stack of layers (of Fig. 1) is etched such that for each layer a length in a direction of a write current flow (see also Figs. 6 and paragraphs 0030-0031 on the write current flow direction) exceeds a width of a corresponding layer with a ratio of 1.5 to 3, but does not teach that a similar etching is used to shape the SOT layer structure, including its magnetic layer 10.
Garello teaches an MTJ device (Abstract) in which a SOT layer 110 (Figs. 1a, 1b) has a shape (created by a hard mask 120, Abstract) with a length of 110 (in a direction of a write current) being more than 3 times greater than a width (paragraphs 0015, 0042, 0045).
Guo and Garello teach analogous arts directed to an MTJ device with a SOT layer that does not need an external magnetic layer for operation, and one of ordinary skill in the art before the effective date of filing the application would have had a reasonable expectation of success in modifying the Guo device in view of the Garello device, since they are from the same field of endeavor, and Garello created a successfully operated MTJ device.
It would have been obvious for one of ordinary skill in the art before filing the application to modify the Guo device of Claim 1 and the method of its manufacturing per Claim 15 by shaping a SOT layer structure (including the magnetic layer), per Garello, to have a length, in the direction of the write current, more than 3 times larger than its width (in the orthogonal direction), when such modification is beneficial for SOT-controlled switching (Garello, paragraph 0005).
In re Claims 6 and 18, Guo/Garello teaches the MTJ device according to Claim 5 and the method of manufacturing the MTJ device of Claim 17 as cited above, wherein, as shown for Claims 5 and 17, a length-to-width ratio of the magnetic layer is 3:1 or greater.
In re Claim 8, Guo teaches the MTJ device according to Claim 1 as cited above, but does not teach that the SOT layer structure further includes a topological insulator layer including a material selected from the group consisting of BixSe₁-ₓ, BixSb1-x, and (Bi, Sb)₂Te₃.
Garello teaches that a SOT layer 110 (Fig. 1, paragraphs 0037-0038) comprises a combination of layers including a topological insulator chosen from a group consisting from BixSe₁-ₓ, BixSb1-x, and (Bi, Sb)₂Te₃.
It would have been obvious for one of ordinary skill in the art before filing the application to modify the Guo device of Claim 1 by incorporating into its SOT layer structure a topological insulator chosen from the group consisting of BixSe₁-ₓ, BixSb1-x, and (Bi, Sb)₂Te₃, when desired: “It has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice”, In re Leshin, 125 USPQ 416.
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Guo in view of Gupta et al. (US 2022/0189523).
In re Claim 14, Guo teaches the MTJ device according to Claim 1 as cited above, but does not teach (at least, explicitly) the device comprising a plurality of MTJ elements, wherein the SOT layer structure is common to the plurality of MTJ elements.
Gupta teaches an MTJ device (Abstract) comprised a plurality of MTJ elements 41, 42 (Figs. 1a, 1b, paragraphs 0088, 0089) disposed on a common SOT layer structure 30 (paragraph 0086).
Guo and Gupta teach analogous arts directed to the MTJ device comprised an MTJ stack disposed on a SOT layer structure, and one of ordinary skill in the art before the effective date of filing the application would have had a reasonable expectation of success in modifying the Guo device in view of the Gupta device, since they are from the same field of endeavor, and Gupta created a successfully operated device.
It would have been obvious for one of ordinary skill in the art before the effective date of filing the application to modify the Guo MTJ device to comprise to plurality of MTJ elements, all on the same SOT layer structure, wherein it is desirable to have a structure comprised more than one MTJ elements.
Conclusion
Any inquiry concerning this communication should be directed to GALINA G YUSHINA whose telephone number is 571-270-7440. The Examiner can normally be reached between 8 AM - 7 PM Pacific Time (Flexible). Examiner interviews are available. To schedule an interview, Applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the Examiner by telephone are unsuccessful, the Examiner’s Supervisor, Lynne Gurley can be reached on 571-272-1670.
The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300; a fax phone number of Galina Yushina is 571-270-8440.
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/GALINA G YUSHINA/Primary Patent Examiner, Art Unit 2811, TC 2800,
United States Patent and Trademark Office
E-mail: galina.yushina@USPTO.gov
Phone: 571-270-7440
Date: 01/23/26