Prosecution Insights
Last updated: April 19, 2026
Application No. 18/727,425

MAGNETORESISTIVE ELEMENT HAVING THERMALLY ROBUST PERFORMANCES AFTER HIGH-FIELD EXPOSURE AND SENSOR COMPRISING THE MAGNETORESISTIVE ELEMENT

Non-Final OA §102§103
Filed
Jul 09, 2024
Examiner
MCANDREW, CHRISTOPHER P
Art Unit
2858
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Allegro MicroSystems, LLC
OA Round
1 (Non-Final)
86%
Grant Probability
Favorable
1-2
OA Rounds
2y 5m
To Grant
99%
With Interview

Examiner Intelligence

Grants 86% — above average
86%
Career Allow Rate
820 granted / 957 resolved
+17.7% vs TC avg
Moderate +14% lift
Without
With
+14.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 5m
Avg Prosecution
22 currently pending
Career history
979
Total Applications
across all art units

Statute-Specific Performance

§101
1.8%
-38.2% vs TC avg
§103
46.4%
+6.4% vs TC avg
§102
31.8%
-8.2% vs TC avg
§112
15.9%
-24.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 957 resolved cases

Office Action

§102 §103
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 . Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claims 1-2, 6-7, 9-10, 12-15, 17, & 19 are rejected under 35 U.S.C. 102(a)(1) & (a)(2) as being anticipated by Raberg et al (U.S. PGPub # 20170168122). Regarding Independent claim 1, Raberg teaches: Magnetoresistive element (Fig. 7 Element 700. See paragraphs 0067-0071.), comprising a reference layer (Fig. 7 Element 750. See paragraphs 0067-0071.) having a fixed reference magnetization (Fig. 7 Element 755. See paragraphs 0067-0071.); a ferromagnetic sense layer (Fig. 7 Element 770. See paragraphs 0067-0071.) having a free sense magnetization (Fig. 7 Element 770. See paragraphs 0067-0071.) having a stable vortex configuration (Fig. 7 Element 775. See paragraphs 0067-0071.) that is orientable relative to the fixed reference magnetization in the presence of an external magnetic field (Fig. 7 Element 775. See paragraphs 0067-0071.); and a tunnel barrier layer (Fig. 7 Element 760. See paragraphs 0067-0071.) between the reference layer and the sense layer and contacting a first side of the sense layer (Fig. 7 Element 760. See paragraphs 0067-0071.); the magnetoresistive element further comprises a hard magnetic layer arranged on a second side of the sense layer opposed to the first side (Fig. 7 & 10 Elements 780, 781, 784, & 785. See paragraphs 0072 & 0085.), the hard magnetic layer being configured to generate an interfacial magnetic coupling between the hard magnetic layer and the sense layer (Fig. 7 Element 770. See paragraphs 0067-0071.) on the second side (Fig. 7 & 10 Elements 780, 784, & 785. See paragraphs 0068, 0072, & 0085.), such as to prevent chirality switching of the sense magnetization after the magnetoresistive element has been submitted to a heat treatment and an external magnetic field above vortex expulsion field (Fig. 7 & 10 Elements 780, 784, & 785. See paragraphs 0068, 0072, & 0085.). PNG media_image1.png 652 632 media_image1.png Greyscale PNG media_image2.png 430 254 media_image2.png Greyscale Regarding claim 2, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg teaches the hard magnetic layer comprises a material having a magnetic coercivity greater than 1000 A/m (Paragraph 0077 wherein the exchange bias fields being between 10 and 100 Oe (approx. 800-8000 A/m).). Regarding claim 6, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg teaches the hard magnetic layer (25) comprises an antiferromagnetic material (Paragraph 0078.). Regarding claim 7, Raberg teaches all elements of claim 6, upon which this claim depends. Raberg teaches the antiferromagnetic material comprises any one, alone or in combination, of: IrMn, FeMn, PtMn, PdMn, CrPdMn, NiMn, CuMnAs, Mn3Sn, Mn2Au, or Cr20 (Paragraph 0078.). Regarding claim 9, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg teaches a mediating layer between the sense layer and the hard magnetic layer, the strength of the interfacial magnetic coupling being adjustable by adjusting the thickness of the mediating layer (See paragraph 0076 wherein the “biasing will be observed if there is some form of coupling” wherein “such coupling may for example be interlayer exchange coupling where free layer 770, a ruthenium layer, a further ferromagnetic layer and antiferromagnetic layer 781, in this order, are in contact.” Any gap would alter the strength from the disclosed contact.). Regarding claim 10, Raberg teaches all elements of claim 9, upon which this claim depends. Raberg teaches the mediating layer comprises a transition metal, particularly Ru, W, Ir, or Ta (See paragraph 0076 wherein the “interlayer exchange coupling where free layer 770, a ruthenium layer, a further ferromagnetic layer and antiferromagnetic layer 781, in this order, are in contact.”). Regarding claim 12, Raberg teaches all elements of claim 11, upon which this claim depends. Raberg teaches a ferromagnetic coupling layer between the mediating layer and the hard magnetic layer; the strength of the interfacial magnetic coupling being further adjustable by adjusting the thickness of the coupling layer (See paragraph 0076 wherein the “interlayer exchange coupling where free layer 770, a ruthenium layer, a further ferromagnetic layer and antiferromagnetic layer 781, in this order, are in contact.”). Regarding claim 13, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg teaches the magnetically soft material of the sense layer comprises a combination of Ni, Fe, Co and transition metals (Fig. 7 Element 770. See paragraph 0077 wherein knife is disclosed.). Regarding claim 14, Raberg teaches all elements of claim 13, upon which this claim depends. Raberg teaches the sense layer has a thickness greater than 15 nm (Fig. 7 Element 770. See paragraph 0077 wherein 30nm is disclosed.). Regarding claim 15, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg teaches the sense layer has a net exchange bias that is lower 40 A/m in any direction in the plane (P) of the sense layer (Fig. 7 Element 770. See paragraphs 0067-0071.). Regarding Independent claim 17, Raberg teaches: Method for manufacturing the magnetoresistive element (See Fig. 7 wherein the magnetoresistive element is disclosed as having been built.) can thus comprises the steps of: forming the reference layer (Fig. 7 Element 750. See paragraphs 0067-0071.), the tunnel barrier layer (Fig. 7 Element 760. See paragraphs 0067-0071.), the sense layer (Fig. 7 Element 750. See paragraphs 0067-0071.), and the hard magnetic layer (Fig. 7 & 10 Elements 780, 781, 784, & 785. See paragraphs 0072 & 0085.); measuring the net exchange bias of the magnetoresistive elements (See Fig. 3 & 4 , the hysteresis curves.); and heating the magnetoresistive element to a heating temperature between 150°C and 400°C “(See the "The proposed homogenously exchange biasing of free layer 770 may further be combined with zero field cooling in an embodiment by adding a tempering process step without external field" in par. 81) until the measured net exchange bias of the magnetoresistive elements is below 40 A/m (the "net exchange bias" is understood as an effective offset of the magnetization curve at zero field, which becomes not apparent from the hysteresis curves in fig. 3, 4 of D 1; the feature is thus disclosed in "hysteresis may vanish" in par. 88 and in the hysteresis curves in fig. 3, 4). PNG media_image1.png 652 632 media_image1.png Greyscale PNG media_image2.png 430 254 media_image2.png Greyscale Regarding claim 19, Raberg teaches all elements of claim 17, upon which this claim depends. Raberg teaches said measuring the net exchange bias is performed by using a magnetometry technique (See Fig. 3 & 4.). 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. The factual inquiries 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. Claims 3-5, 11, & 16 are rejected under 35 U.S.C. 103 as being unpatentable over Raberg et al (U.S. PGPub # 20170168122). Regarding claim 3, Raberg teaches all elements of claim 2, upon which this claim depends. Raberg does not explicitly teach the material comprises any one, alone or in combination, of: CoCrPt, FePt-TiO2, FePt-SiO2, FePt-C, CoPt, NdFeB, or SmCo (See paragraph 0054 teaches another material.). But it would have been obvious to one of ordinary skill in the art before the effective time of filing to have the material comprise any one, alone or in combination, of: CoCrPt, FePt-TiO2, FePt-SiO2, FePt-C, CoPt, NdFeB, or SmCo because these substances are used ubiquitously as hard magnetic materials. Regarding claim 4, Raberg teaches all elements of claim 2, upon which this claim depends. Raberg does not explicitly teach the high magnetic coercivity material comprises any one of: a perpendicular ferrimagnetic alloy comprising a rare earth and a transition metal; a perpendicular ordered alloy, multilayers of 3d-4d metals having perpendicular magnetic anisotropy, a permanent magnet based on one or a plurality of rare earth metals. But it would have been obvious to one of ordinary skill in the art before the effective time of filing to have the high magnetic coercivity material comprises any one of: a perpendicular ferrimagnetic alloy comprising a rare earth and a transition metal; a perpendicular ordered alloy, multilayers of 3d-4d metals having perpendicular magnetic anisotropy, a permanent magnet based on one or a plurality of rare earth metals because these substances are used ubiquitously as hard magnetic materials. Regarding claim 5, Raberg teaches all elements of claim 3, upon which this claim depends. Raberg does not explicitly teach the high magnetic coercivity material further comprises Cr, C, Cu, V, or an oxide. But it would have been obvious to one of ordinary skill in the art before the effective time of filing to have the high magnetic coercivity material further comprises Cr, C, Cu, V, or an oxide because these substances are used ubiquitously as hard magnetic materials. Regarding claim 11, Raberg teaches all elements of claim 9, upon which this claim depends. Raberg does not explicitly teach the thickness of the mediating layer is configured such that the strength of the interfacial magnetic coupling has a value between -1 mJ/m2 and +1 mJ/m2. But it would have been obvious to one of ordinary skill in the art before the effective time of filing to have the thickness of the mediating layer is configured such that the strength of the interfacial magnetic coupling has a value between -1 mJ/m2 and +1 mJ/m2 because the skilled person would adjust the mediating layer thickness to achieve a proper coupling in the claimed range. Regarding Independent claim 16, Raberg teaches: A magnetic sensor (Fig. 7 Element 700. See paragraphs 0067-0071.) comprising a plurality of the magnetoresistive element. Raberg does not explicitly teach: a plurality of the magnetoresistive element. But it would have been obvious to one of ordinary skill in the art before the effective time of filing to have a plurality of the magnetoresistive element because this is a mere duplication of elements wherein the “mere duplication of parts has no patentable significance unless a new and unexpected result is produced.” See MPEP Section 2144.01 VI B. Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Raberg et al (U.S. PGPub # 20170168122) in view of He Luguang et al (Translation of CN 112768603). Regarding claim 8, Raberg teaches all elements of claim 1, upon which this claim depends. Raberg does not explicitly teach the thickness of the hard magnetic layer is between 2nm and to 30nm. He Luguang teaches the thickness of the hard magnetic layer is between 2nm and to 30nm (See Paragraph n0072.). It would have been obvious to one of ordinary skill in the art before the effective time of filing to apply the teachings of He Luguang to the teachings of Raberg such that the thickness of the hard magnetic layer is between 2nm and to 30nm because this is routine optimization technique to generate ideal performance of the magnetoresistive system. Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Raberg et al (U.S. PGPub # 20170168122) in view of Djayaprawira et al (U.S. PGPub # 2014/0024140). Regarding claim 18, Raberg teaches all elements of claim 17, upon which this claim depends. Raberg does not explicitly teach heating the magnetoresistive elements is performed during a heating time that is between 1s and 24h. Djayaprawira teaches heating the magnetoresistive elements is performed during a heating time that is between 1s and 24h (See paragraph 0039.). would have been obvious to one of ordinary skill in the art before the effective time of filing to apply the teachings of Djayaprawira to the teachings of Raberg such that one would heat the magnetoresistive elements is performed during a heating time that is between 1s and 24h because this is how one would anneal the magnetic device to secure “the required magnetization alignment.” (See paragraph 0039 of Djayaprawira.) Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. The prior art listed but not cited represents the previous state of the art and analogous art that teaches some of the limitations claimed by applicant. Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER P MCANDREW whose telephone number is (469)295-9025. The examiner can normally be reached Monday-Thursday 6-4:30. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. 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, Lee Rodak can be reached on 571-270-5628. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /CHRISTOPHER P MCANDREW/Primary Examiner, Art Unit 2858
Read full office action

Prosecution Timeline

Jul 09, 2024
Application Filed
Jan 29, 2026
Non-Final Rejection — §102, §103 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
86%
Grant Probability
99%
With Interview (+14.2%)
2y 5m
Median Time to Grant
Low
PTA Risk
Based on 957 resolved cases by this examiner. Grant probability derived from career allow rate.

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