Ex Parte Siddik et al

Patent Trial and Appeal Board

Feb 19, 2019

14193979 (P.T.A.B. Feb. 19, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
14/193,979 02/28/2014
63162 7590 02/21/2019
TRASK BRITT, P.C./ MICRON TECHNOLOGY
P.O. BOX 2550
SALT LAKE CITY, UT 84110
Manzar Siddik
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
2269-12111(2013-0519.00) 2806
EXAMINER
ALBRECHT, PETER M
ART UNIT PAPER NUMBER
2811
NOTIFICATION DATE DELIVERY MODE
02/21/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
USPTOMail@traskbritt.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MANZAR SIDDIK and WITOLD KULA
Appeal 2018-004117
Application 14/193,979
Technology Center 2800
Before LINDA M. GAUDETTE, N. WHITNEY WILSON, and LILAN REN,
Administrative Patent Judges.
GAUDETTE, Administrative Patent Judge.
DECISION ON APPEAL 1
1 This Decision includes citations to the following documents: Specification filed
Feb. 28, 2014 ("Spec."); Final Office Action dated Feb. 23, 2017 ("Final Act.");
Appeal Brief filed Sept. 7, 2017 ("Appeal Br."); and Examiner's Answer dated
Jan. 17, 2018 ("Ans."). We have also considered, but do not cite to, the Reply Brief
filed Mar. 9, 2018.
Appeal 2018-004117
Application 14/193,979
The Appellant2 appeals under 35 U.S.C. § 134(a) from the Examiner's
decision finally rejecting claims 1-11, 31, and 32. Appeal Br. 5. We have
jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
The invention "relates to design and fabrication of memory cells
characterized as spin torque transfer magnetic random access memory (STT-
MRAM) cells." Spec. ,r 1. Claim 1, the sole independent claim on appeal, is
reproduced below.
1. A memory cell, comprising:
a magnetic cell core comprising:
a magnetic region comprising a depleted magnetic
material, the depleted magnetic material formed
from a precursor magnetic material, the precursor
magnetic material comprising a diffusible species
and at least one other species, the depleted
magnetic material comprising the at least one other
species;
another magnetic region;
an intermediate oxide region between the magnetic
region and the another magnetic region;
an amorphous region proximate to the magnetic region,
the amorphous region comprising an attracter
material having a chemical affinity for the
diffusible species that is higher than a chemical
affinity of the at least one other species for the
diffusible species, the amorphous region
comprising both the attracter material and at least a
portion of the diffusible species from the precursor
magnetic material; and
2 The Appellant is the Applicant, Micron Technology, Inc., also identified as the
real party in interest. Appeal Br. 4.
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Application 14/193,979
another oxide region comprising a nonmagnetic oxide
material, the nonmagnetic oxide material being in
direct physical contact with the amorphous region.
Appeal Br. Claims Appendix 1.
The Examiner relies on the following prior art references as evidence of
unpatentability of the appealed claims:
Nagamine US 2008/0253039 Al Oct. 16, 2008
Chen US 2011/0064969 Al Mar. 17, 2011
Ohmori US 2012/0061781 Al Mar. 15, 2012
Komagaki US 8/514,527 B2 Aug.20,2013
Oguz US 2014/0084398 Al Mar. 27, 2014
Kim US 2014/0327095 Al Nov. 6, 2014
The claims stand finally rejected as unpatentable under 35 U.S.C. § 103 as
follows:
1. claims 1-3, 6, 7, 10, and 11 over Oguz in view of Chen;
2. claims 4 and 5 over Oguz in view of Chen and Ohmori;
3. claims 8 and 9 over Oguz in view of Chen and Komagaki;
4. claim 31 over Oguz in view of Chen and Nagamine; and
5. claims 5 and 32 over Oguz in view of Chen and Kim.
The Examiner finds "Oguz and Chen ... are directed to spin torquetransfer
magnetic random access memory (STT-MRAM) devices including magnetic
tunnel junctions." Final Act. 4. The Examiner cites Oguz Figure IB and
corresponding description thereof in support of a finding that Oguz discloses the
invention as recited in claim 1 with the exception of "another oxide region" ( claim
1, last paragraph). Id. at 2--4. As to the claimed "amorphous region," the Examiner
finds this limitation reads on Oguz's crystallization barrier layer 112 that
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Application 14/193,979
comprises at least one of Ta, Ru, W, V, Mo, Nb, and Cr. Id. at 3 ( citing Oguz
,r,r 29, 30).
The Examiner finds Chen discloses a seed layer positioned between free
layer 130' (a magnetic region) and substrate 1. Id. at 4 ( citing Chen Fig. 2B, ,r,r 34,
35). The Examiner finds Chen discloses that the seed layer can "improve texture
for perpendicular properties, improve interfacial properties for stack growth and
tunneling magnetoresistance, act as a stop layer for interdiffusion, ensure stack
stability, and/or shield the magnetic layers from stray magnetic fields." Id. at 4--5
( citing Chen ,r 35). The Examiner finds Chen discloses vanadium oxide is a
suitable material for use as the seed layer. Ans. 15. The Examiner finds a
vanadium oxide seed layer is both uniformly amorphous and non-magnetic. Id. The
Examiner determines the broadest reasonable interpretations of the claim terms "an
amorphous region" and "another oxide region" read on an upper portion of Chen's
seed layer (designated by the Examiner as an upper sublayer) and a lower portion
of Chen's seed layer (designated by the Examiner as a lower sublayer),
respectively, the upper and lower sublayers being identical in composition and
structure. Id. at 14--16. The Examiner thus finds Chen discloses an amorphous
region (the upper sublayer) proximate to a magnetic region (free layer 130') and in
direct physical contact with another oxide region comprising a nonmagnetic oxide
material (the lower sublayer). Id. at 16; see also Final Act. 4.
Based on the Examiner's findings that both Oguz and Chen disclose
structures comprising an amorphous region proximate a magnetic region, and that
Chen discloses benefits provided by a seed layer comprising the amorphous region
in direct physical contact with an oxide region, the Examiner further finds one of
ordinary skill in the art at the time of the invention would have modified Oguz's
device to include another oxide region comprising a nonmagnetic oxide material,
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Application 14/193,979
positioned so as to be in direct physical contact with Oguz's amorphous region
( crystallization barrier layer 112) to achieve the benefits described in Chen. Final
Act. 4--5.
The Appellant argues the evidence of record does not support the
Examiner's finding that Chen discloses or suggests the addition of another oxide
region to Oguz's multilayer structure. See, e.g., Appeal Br. 23 ("[T]he Examiner's
asserted interpretation of Chen as teaching, particularly, a seed layer with a
multilayer structure and including, particularly, a lower sublayer as another oxide
region and an upper sublayer as an amorphous region inappropriately reads
specifics into Chen's seed/capping layer that are not actually taught or suggested
by Chen."). The Appellant's argument is persuasive.
The Examiner's reasoning improperly conflates two distinct issues: ( 1) Do
the broadest reasonable constructions of the claim limitations "an amorphous
region" and "another oxide region" read on upper and lower portions of Chen's
seed layer; and (2) would the ordinary artisan at the time of the invention have had
a reason to include another oxide region in Oguz's multilayer structure based on
Chen's disclosure of benefits provided by the seed layer. In other words, the
Examiner's determination that the claim limitations "an amorphous region" and
"another oxide region" read on upper and lower regions of Chen's seed layer, even
if correct, does not establish that Chen discloses a seed layer comprising an oxide
region in direct physical contact with an amorphous region, or that the ordinary
artisan reasonably would have understood from Chen's disclosure, that adding an
oxide region to Oguz's multilayer structure such that the oxide region is in direct
physical contact with Oguz's amorphous region, would provide any of the benefits
that are said to be provided to Chen's structure by the seed layer. As argued by the
Appellant, although Chen discloses that the seed layer can be "a single layer or
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multilayer in structure, crystalline or amorphous in state, metal or oxide, magnetic
or non-magnetic," the Examiner has not explained persuasively why the ordinary
artisan, without the benefit of the present Specification, would have understood
Chen as teaching or suggesting a structure comprising a seed layer having an oxide
region and an amorphous region that are in direct physical contact, and a magnetic
region proximate the amorphous region. Appeal Br. 23 (quoting Chen ,r 35).
CONCLUSION
The Appellant has argued persuasively that the Examiner's conclusion of
obviousness is based on impermissible hindsight reasoning. Accordingly, we do
not sustain the rejections of claims 1-11, 31, and 3 2.
REVERSED
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