Ex Parte Wen et al

Patent Trial and Appeal Board

Jul 26, 2018

14728683 (P.T.A.B. Jul. 26, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/728,683 06/02/2015
23494 7590 07/30/2018
TEXAS INSTRUMENTS IN CORPORA TED
PO BOX 655474, MIS 3999
DALLAS, TX 75265
UNITED ST A TES OF AMERICA
FIRST NAMED INVENTOR
Huang-Chun Wen
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.
TI-75481 4159
EXAMINER
GRAYBILL, DAVIDE
ART UNIT PAPER NUMBER
2894
NOTIFICATION DATE DELIVERY MODE
07/30/2018 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):
uspto@ti.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte HUANG-CHUN WEN, RICHARD ALLEN BAILEY,
ANTONIO GUILLERMO ACOSTA, JOHN A. RODRIGUEZ,
SCOTT ROBERT SUMMERFELT, and KEMAL TAMER SAN
Appeal2018-002825
Application 14/728,683
Technology Center 2800
Before KAREN M. HASTINGS, N. WHITNEY WILSON, and
CHRISTOPHER L. OGDEN, Administrative Patent Judges.
OGDEN, Administrative Patent Judge.
DECISION ON APPEAL
Appellant1 appeal under 35 U.S.C. § 134(a) from the Examiner's final
decision rejecting claims 1-3, 5-12, and 21-23 in the above-identified
application. 2 We have authority pursuant to 35 U.S.C. § 6(b ). We affirm.
1 Appellant is Texas Instruments Incorporated, which is also, according to
the Brief, the real party in interest. Appeal Brief 2 (July 18, 2017)
[hereinafter Br.].
2 The appeal record includes the following: Final Office Action, Mar. 7, 2017
[hereinafter Final Action]; Br.; Examiner's Answer, Oct. 23, 2017
[hereinafter Answer]. Appellant did not file a reply brief.
Appeal2018-002825
Application 14/728,683
BACKGROUND
Appellant's invention relates to a method of manufacturing an
integrated circuit with ferroelectric memories such as ferroelectric random
access memory (FRAMs ). See Abstract, Spec. ,r 31. 3 According to
Appellant, the inventors have discovered an approach "for curing a
passivation film ... at the surface of a ferroelectric integrated circuit," so as
to impart "beneficial compressive stress ... without degrading the
polarization of that ferroelectric material." Spec. ,r 33. As representative of
the invention, we reproduce independent claim 1 below:
1. A method of manufacturing an integrated circuit,
compnsmg:
forming at least one circuit element comprising a layer of
a ferroelectric material near a semiconducting surface of a body,
wherein the at least one circuit element comprises a
ferroelectric capacitor;
then forming at least one level of conductors overlying
the element, each level comprising patterned metal conductors
and a dielectric layer;
forming a protective overcoat layer over the surface and
overlying the at least one circuit element and the at least one
level of conductors;
then depositing a passivation layer over the protective
overcoat layer;
polarizing the ferroelectric capacitor; and
after polarizing the ferroelectric capacitor, heating the
passivation layer to a temperature below a Curie temperature of
the ferroelectric material for a duration sufficient to cure the
material of the passivation layer into a tensile stress state, and
of less than about twenty minutes.
Br. 17 (emphasis of key phrase added). Claims 2, 3, 5-12, and 21-23
depend from claim 1. See id. at 1 7-19.
3 Specification, June 2, 2015 [hereinafter Spec.].
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Appeal2018-002825
Application 14/728,683
The Examiner rejects claims 1-3, 5-7, 9, 10, 12, 21 and 22 under 35
U.S.C. § 103 as being unpatentable over the combination of Sashida, 4 Jung, 5
and applicant's admitted prior art ("AAPA"). Final Action 9-21.
Alternatively, the Examiner rejects the claims over the same references, and
further in view of Cross. 6 Final Action 21-22.
The Examiner rejects claims 8 and 23 under 35 U.S.C. § 103 as being
unpatentable over the combination of Sashida, Jung, the AAPA, and
( optionally) Cross, in further combination with Ahmad. 7 Final Action 22.
The Examiner rejects claims 21 and 22 under 35 U.S.C. § 103 as being
unpatentable over the combination of Sashida, Jung, the AAPA, ( optionally)
Cross, and in further combination with Summerfelt. 8 Final Action 30-31.
Examiner rejects claim 23, alternatively, under 35 U.S.C. § 103 as
being unpatentable over the combination of Sashida, Jung, the AAPA,
(optionally) Cross, and Ahmad, as evidenced by ( or further in combination
with) Nandu. 9 Final Action 31-32.
Appellant argues the claims as a group with respect to each ground of
rejection, and only makes distinct arguments regarding the rejection of claim
1 over the combination of Sashida, Jung, and the AAPA. See Appeal Br. 5-
4 Sashida, US 2004/0046185 Al (published Mar. 11, 2004).
5 Jung et al., US 2011/0311796 Al (published Dec. 22, 2011) [hereinafter
Jung].
6 Cross et al., US 2006/0211156 Al (published Sep. 21, 2006) [hereinafter
Cross].
7 Ahmad et al., US 7,939,456 B2 (issued May 10, 2011) [hereinafter
Ahmad].
8 Summerfelt et al., US 2010/0296329 Al (published Nov. 25, 2010)
[hereinafter Summerfelt].
9 Nandu et al., US 2003/0234459 Al (published Dec. 25, 2003) [hereinafter
Nandu].
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Appeal2018-002825
Application 14/728,683
15. Therefore, consistent with 37 C.F.R. § 4I.37(c)(l)(iv), we limit our
discussion to the rejection of independent claim 1 based on this ground.
Claims 2, 3, 5-12, and 21-23 fall with claim 1. 10
DISCUSSION
Among other limitations, independent claim 1 requires "polarizing the
ferroelectric capacitor; and after polarizing the ferroelectric capacitor,
heating the passivation layer." Appeal Br. 17. The Examiner determines that
the combination of Sashida, Jung, and the AAPA teaches all the limitations
of claim 1 except that it does not explicitly disclose the order of the
polarizing and heating steps. Final Action 20. However, the Examiner
determines that the sequence of these two steps would have been an
obvious matter of design choice bounded by well known manu-
facturing constraints and ascertainable by routine experimenta-
tion and optimization to choose the particular claimed process
sequence because applicant has not disclosed that, in view of the
applied prior art, the limitation is for a particular unobvious pur-
pose, produces an unexpected result, or is otherwise critical.
Id. According to the Examiner, "in a well known process, the order of
performing process steps is prima facia obvious in the absence of
unexpected results." Id. at 20-21 (citing, e.g., In re Burhans, 154 F.2d 690
(CCPA 1946); In re Gibson, 39 F.2d 975 (CCPA 1930)).
10 Although the Examiner indicates that dependent claim 11 was finally
rejected (Final Action 1 ), the Examiner does not appear to provide specific
grounds for rejecting dependent claim 11. However, Appellant does not
identify this as error. See In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)
("[I]t has long been the Board's practice to require an applicant to identify
the alleged error in the examiner's rejections.").
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Appeal2018-002825
Application 14/728,683
Appellant argues that the Examiner erred by using "common sense to
supply a missing limitation." Br. 7 (emphasis omitted). We disagree. The
Examiner properly reasoned that absent evidence to the contrary, the
ordering of the polarizing and heating steps, otherwise known in the art,
would have been within the level of ordinary skill in the art at the time of
invention. See Final Action 20. On this appeal record, we agree that the
Examiner has made a prima facie showing that the ordering of the polarizing
and heating steps, otherwise known in the art, "constitute[] nothing more
than conventional manufacturing steps that implement principles disclosed
in the prior art" and routine experimentation. Merck Sharp & Dahme Corp.
v. Hospira, Inc., 874 F.3d 724, 729 (Fed. Cir. 2017).
Appellant further argues that the ordering of these steps is "not an
obvious matter of design choice because the resulting method does, in fact,
produce unexpected results." Br. 8. According to the Appellant, "it is
generally not desirable to expose ferroelectric memory cells to high
temperatures while they are in a polarized state because of an effect know as
imprinting." Id. (citing TEXAS INSTRUMENTS INC., MSP430â„¢ FRAM
QUALITY AND RELIABILITY (rev. 2014),http://http://www.ti.com/lit/an/
slaa526a/slaa526a.pdf [hereinafter TI Report]). Appellant argues that
"imprinting causes a ferroelectric memory cell to prefer a particular state,
whereas an ideal case is for a ferroelectric memory cell to be neutral ( e.g.
have no preference) for on logic state over the other." Id. at 9 (citing TI
Report § 2.1.2). Appellant argues that, contrary to this expectation, the
claimed invention provides the benefit of causing a compressive stress on the
underlying circuit elements, thus enhancing the polarization characteristics
of the ferroelectric material, rather than weakening them by the imprinting
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Appeal2018-002825
Application 14/728,683
effect. Id. (citing Spec. ,r,r 51-53). Appellant argues that this result is
unexpected, because "one skilled in the art would typically expect that
subjecting polarized ferroelectric material to high temperatures would
worsen, rather than improve, the performance of the ferroelectric material."
Id. at 10.
These arguments are not persuasive of reversible error. Appellant has
the burden to establish unexpected results. See In re Geisler, 116 F.3d 1465
1469-70 (Fed. Cir. 1997). In doing so, Appellant must establish "(1) that
there actually is a difference between the results obtained through the
claimed invention and those of the prior art, ... and (2) that the difference
actually obtained would not have been expected by one skilled in the art at
the time of invention." In re Freeman, 474 F.2d 1318, 1324 (CCPA 1973)
( citation omitted). As evidence of unexpected results, Appellant may not
rely on the TI Report, because Appellant introduced it for the first time in the
Appeal Brief, and the Examiner refused to admit it as evidence. See Answer
5 (citing 37 C.F.R. § 4I.37(c)(2)). According to 37 C.F.R. § 4I.37(c)(2),
"[r]eview of an examiner's refusal to admit ... Evidence is by petition
[under 37 C.F.R. § 1.181]," yet the record does not show that any such
petition was filed or granted. Consequently, the TI Report is not in the
record and cannot be considered as evidence of unexpected results.
In addition to the TI Report, Appellant relies on paragraphs 51-53 of
the Specification for evidence of unexpected results. Appeal Br. 9. This
passage states that polarization characteristics are "further enhanced in those
cases in which the ferroelectric material is programmed (i.e., polarized) prior
to [the] cure process," Spec. ,r 51, although "significant enhancement in the
polarization characteristics of the ferroelectric material is still attained even
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Appeal2018-002825
Application 14/728,683
without the additional benefit of the pre-polzarization of the ferroelectric
material," id. ,r 53. These conclusory statements do not refer to factual data
such as experimental results, and make no direct comparison to the closest
prior art, and are thus insufficient to establish unexpected results. See In re
De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984) ("It is well settled that
unexpected results must be established by factual evidence. Mere argument
or conclusory statements in the specification does not suffice."); In re Baxter
Travenol Labs., 952 F.2d 388, 392 (Fed. Cir. 1991) ("[W]hen unexpected
results are used as evidence of nonobviousness, the results must be shown to
be unexpected compared with the closest prior art.").
For the above reasons, the preponderance of the evidence supports the
Examiner's conclusion of obviousness. We therefore affirm the rejection of
claims 1-3, 5-12, and 21-23.
DECISION
The Examiner's decision is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended. See 37 C.F.R. §§ 1.136(a)(l )(iv), 41.50(±)
(2016).
AFFIRMED
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