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 .
Information Disclosure Statement
Acknowledgement is made of Applicant's Information Disclosure Statement (IDS) from PTO-1449, that was filed on 12/22/2025. The IDS has been considered.
Claim Rejections - 35 USC § 112
Prior rejection of Claim 3 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, is withdrawn in view of applicant’s amendments to claim 3.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 11 and 15-16 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Pi et al. (US 2015/0008547 A1, newly cited).
Re Claim 11, Pi teaches a magnetoresistive memory device comprising:
a lower electrode (10, Fig. 1, para [0030]);
a lower magnetic material layer (12, Fig. 1, para [0031]) on the lower electrode (10);
a tunnel barrier layer (16, Fig. 1, para [0030]) on the lower magnetic material layer (12);
an upper magnetic material layer (17, Fig. 1, paras [0030] and [0034]) on the tunnel barrier layer (16), the upper magnetic material layer having a variable magnetization direction (17 is a free layer);
a cap structure (22+23, Fig. 1, para [0040]) on the upper magnetic material layer (17), the cap structure comprising an amorphous oxide (para [0040]);
a cap conductive layer (24, Fig. 1, para [0044]) on the cap structure (22+23); and
an upper electrode (30, Fig. 1, para [0030]) on the cap conductive layer (24), wherein the cap structure (22+23, where each layer can be 3 Å, with a total of 6 Å, for example, for capping structure MgO/TaOx, the thicknesses for MgO and TaOx can each be 3 Å, para [0052]) has a greater thickness than the upper magnetic material layer (layer 17 can be 5 Å, para [0037]).
Re Claim 15, Pi teaches the magnetoresistive memory device of claim 11, wherein the thickness of the cap structure (thickness of cap structure can be 6 Å, see claim 11 above) is smaller than or equal to about twice the thickness of the upper magnetic material layer (thickness of layer 17 can be 5 Å, see claim 11 above, and hence twice this thickness would be 10 Å, which is greater than the thickness of the cap structure).
Re Claim 16, Pi teaches the magnetoresistive memory device of claim 11, wherein the cap conductive layer (24, Fig. 1, para [0044]) has a greater thickness (layer 24 constitutes the top oxide layer and can have a thickness of 10 Å, for example in the stack of MgO/TaOx/VOx, VOx is the top oxide layer 24 and it can be 10 Å, para [0052]) than each of the upper magnetic material layer (thickness of layer 17 can be 5 Å, see claim 11 above) and the cap structure (thickness of cap structure can be 6 Å, see claim 11 above).
Rejection 2
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 11 and 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Rahman et al. (US 2019/0378972 A1), and further in view of Chen et al. (US 2010/0109109 A1).
Re Claim 11, Rahman teaches a magnetoresistive memory device comprising:
a lower electrode (104, Fig. 2A, para [0021]);
a lower magnetic material layer (102, Fig. 2A, para [0021]) on the lower electrode (104);
a tunnel barrier layer (106, Fig. 2A, para [0021]) on the lower magnetic material layer (102);
an upper magnetic material layer (lowermost 114 layer that is in contact with 106 layer, Fig. 2A, para [0022]) on the tunnel barrier layer (106), the upper magnetic material layer having a variable magnetization direction (114 is a free layer and hence have variable magnetization direction, para [0023]);
a cap structure (112+114 bilayer structure, except the lowermost 114, Fig. 2A, para [0022]) on the upper magnetic material layer (lowermost 114 layer),
a cap conductive layer (120, Fig. 2A, para [0028]) on the cap structure (112+114 bilayer structure); and
an upper electrode (122, Fig. 2A, para [0032]) on the cap conductive layer (120),
wherein the cap structure has a greater thickness (the number of bilayers 112+114 can be between 2-12, para [0022]; assuming there are five bilayers of 112+114, excluding the lowermost 114 layer, 112 and 114 layers have a thickness of 0.01 nm and 0.15 nm each, paras [0023] - [0024], the total thickness of the cap structure would be 5*(0.01+0.15) = 0.80 nm) than the upper magnetic material layer (thickness of lowermost 114 layer is at least 0.45 nm, para [0023], which is smaller than the thickness of the cap structure).
Rahman states that the cap structure (112+114 bilayer structure) can comprise of non-magnetic layers (112 layers) made of metals like molybdenum, ruthenium, tungsten and tantalum, and the magnetic layers (114 layers) can be made of alloys such as alloy such as CoFe and CoFeB. Rahman is silent about the cap structure comprising an amorphous oxide. However, in a related semiconductor art, Chen teaches a cap structure 116+118 (Fig. 1, para [0032]) formed on the free layer 114 (Fig. 1, para [0032]). The cap structure 116+118 is formed of a non-magnetic layer 116 and a magnetic layer 118, where the magnetic layer 118 can be made of magnetic alloy of NiFe, Ni or CoFeB, and the non-magnetic material can be Ta, Ru, Mg, Ti, Cu, Cr, Ag, Pt, Pd, Au, tantalum oxide (TaO), ruthenium oxide (RuO), MgO or titanium oxide (TiO).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, absent unexpected results, to modify the memory device of Rahman, such that the non-magnetic layers of Rahman are made of oxides such as tantalum oxide (TaO), ruthenium oxide (RuO), MgO or titanium oxide (TiO), as taught by Chen. Chen teaches that metal oxides can be alternative materials for a non-magnetic layer, and one of ordinary skill in the art would have found it obvious to substitute a metal oxide like tantalum oxide instead of tantalum to use as a non-magnetic layer. The substitution of a known material for its known purpose to yield predictable results is prima facie obvious. Also see KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Additionally, Rahman modified by Chen does not explicitly disclose that the oxide layer of the cap structure is amorphous. Chen states that the non-magnetic layers can be made of oxides such as tantalum oxide (TaO), ruthenium oxide (RuO), MgO or titanium oxide (TiO), but does not explicitly state if they are amorphous or crystalline. One of ordinary skill in the art would realize that there are only two predictable outcomes – the oxide layer can be either crystalline or amorphous. Therefore, a person of ordinary skill has good reason to pursue the known options and reach the claimed limitation with anticipated success, see KSR, 550 U.S. at 421, 82 USPQ2d at 1397.
Re Claim 15, Rahman modified by Chen teaches the magnetoresistive memory device of claim 11, wherein the thickness of the cap structure (thickness of cap structure can be 0.80 nm, see claim 11 above) is smaller than or equal to about twice the thickness of the upper magnetic material layer (thickness of lowermost 114 layer is at least 0.45 nm, see claim 11 above, and hence twice this thickness would be 0.90 nm, which is greater than the thickness of the cap structure).
Re Claim 16, Rahman modified by Chen teaches the magnetoresistive memory device of claim 11, wherein the cap conductive layer has a greater thickness (layer 120 can have a thickness of 6 nm, para [0029], Rahman) than each of the upper magnetic material layer (thickness of lowermost 114 layer can be 0.45 nm, see claim 11 above) and the cap structure (thickness of cap structure can be 0.80 nm, see claim 11 above for calculation).
Re Claim 17, Rahman modified by Chen teaches the magnetoresistive memory device of claim 11, further comprising: a first interconnection (502, Fig. 5, para [0074], Rahman) electrically connected to the lower electrode (104); and a second interconnection (marked “2nd interconnection” in annotated Fig. 5 below) on the upper electrode (122) and electrically connected to the upper electrode (see Fig. 5).
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Allowable Subject Matter
Claims 1-4, 6-7, 10, 18-20 and 28 are allowed.
Claims 12-14 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Claim 1 is allowable for at least the following reasons. Most of the limitation of claim 1 are taught by Rahman et al. (US 2019/0378972 A1, of record), as stated in the Office Action dated 10/17/2025. Rahman also teaches the newly added limitation wherein, “the upper magnetic material layer having a variable magnetization direction (lowermost 114 layer is a free layer, Fig. 2A, paras [0022] – [0023])”. However, the newly amended limitation, wherein “the cap structure comprising first oxide layers and second oxide layers which are alternately stacked” is neither anticipated nor made obvious by the prior art of record, when viewed in the context of the whole claim. Rahman in view of Chen et al. (US 2010/0109109 A1, of record) teaches a cap structure with one oxide layer and does not teach second oxide layers (see rejection of claim 11 above). Related art, Pi et al. (US 2015/0008547 A1, newly cited) teaches most of the limitations of claim 1 (similar to rejection of claim 11 above), and also teaches a cap structure of oxide bilayer (22+23, Fig. 1, para [0040], see claim 11 rejection above). However, Pi fails to teach a plurality of first oxide layers and a plurality of second oxide layers that are alternately stacked, as required in claim 1.
Claims 2-4, 6-7, 10 and 28 depend from claim 1 and are allowable for at least the reasons above.
Claim 18 is allowable for at least the following reasons. Most of the limitation of claim 1 are taught by Rahman et al. (US 2019/0378972 A1, of record), and further in view of Kim et al. (US 2013/0234267 A1) and Chen et al. (US 2010/0109109 A1), as stated in the Office Action dated 10/17/2025. Rahman also teaches the newly added limitation wherein, “the upper magnetic material layer having a variable magnetization direction (lowermost 114 layer is a free layer, Fig. 2A, paras [0022] – [0023])”. However, the newly amended limitation, wherein “the cap structure comprises multilayer structures of oxide in which a unit structure including a first oxide layer and a second oxide layer is repeatedly stacked at least twice” is neither anticipated nor made obvious by the prior art of record, when viewed in the context of the whole claim. Rahman in view of Chen et al. (US 2010/0109109 A1, of record) teaches a cap structure with one oxide layer and does not teach second oxide layers (see rejection of claim 11 above). Related art, Pi et al. (US 2015/0008547 A1, newly cited) teaches most of the limitations of claim 1 (similar to rejection of claim 11 above), and also teaches a cap structure of oxide bilayer (22+23, Fig. 1, para [0040], see claim 11 rejection above). However, Pi fails to teach a plurality of first oxide layers and a plurality of second oxide layers, and hence does not teach “a unit structure including a first oxide layer and a second oxide layer is repeatedly stacked at least twice”, as required in claim 18.
Claims 19-20 depend from claim 18 and are allowable for at least the reasons above.
Claim 12 is allowable for at least the reasons of, “wherein the cap structure comprises multilayer structures of oxide in which a unit structure comprising a first oxide layer and a second oxide layer is repeatedly stacked at least twice”. The prior art of record taken either single or in combination fails to teach or reasonably suggest the above limitation when taken in context of the independent claim 11, as a whole. Rahman in view of Chen et al. (US 2010/0109109 A1, of record) teaches a cap structure with one oxide layer and does not teach second oxide layers. Pi et al. (US 2015/0008547 A1, newly cited) teaches a cap structure of oxide bilayer (22+23, Fig. 1, para [0040], see claim 11 rejection above), where the first oxide layer may comprise a non-magnetic material and the second oxide layer may comprise a magnetic material (see para [0040], Pi). However, Pi fails to teach a plurality of first oxide layers and a plurality of second oxide layers, and hence does not teach “a unit structure comprising a first oxide layer and a second oxide layer is repeatedly stacked at least twice”.
Claim 13 is allowable for at least the reasons of, “wherein the amorphous oxide is a multilayer structure of oxide of Ta/CoFeB/Ta/CoFeB”. The prior art of record taken either single or in combination fails to teach or reasonably suggest the above limitation when taken in context of the independent claim 11, as a whole.
Claim 14 is allowable for at least the reasons of, “wherein the amorphous oxide is a multilayer structure of oxide of Ta/CoFeB/Ta/CoFeB/Ta/CoFeB”. The prior art of record taken either single or in combination fails to teach or reasonably suggest the above limitation when taken in context of the independent claim 11, as a whole.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Response to Arguments
Applicant’s arguments with respect to claim 11 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/P.D./Examiner, Art Unit 2898 /JULIO J MALDONADO/Supervisory Patent Examiner, Art Unit 2898