Ex Parte Pacha et al

Patent Trial and Appeal Board

Mar 30, 2016

13270592 (P.T.A.B. Mar. 30, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/270,592 10/11/2011
51092 7590 04/01/2016
ESCHWEILER & AS SOCIA TES LLC
629 EUCLID A VENUE, SUITE 1000
NATIONAL CITY BUILDING
CLEVELAND, OH 44114
FIRST NAMED INVENTOR
Christian Pacha
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.
INFAP242USA 2293
EXAMINER
LAPPAS, JASON
ART UNIT PAPER NUMBER
2827
NOTIFICATION DATE DELIVERY MODE
04/01/2016 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):
Docketing@eschweilerlaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte CHRISTIAN P ACHA, TIM SCHONAUER, and
MICHAEL KUND
Appeal2014-003822
Application 13/270,592
Technology Center 2800
Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
JAMES C. HOUSEL, Administrative Patent Judges.
PERCURIAM.
DECISION ON APPEAL
Appellants 1 filed an appeal under 35 U.S.C. § 134(a) from the Examiner's
decision rejecting claims 1-122 under 35 U.S.C. § 103(a) as being unpatentable
over Liu3 and Datta. 4 We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM-IN-PART. 5
1 Appellants identify the Real Party of Interest as Infineon Technologies AG.
Appeal Br. 1.
2 Claims 13 and 14 have been withdrawn from consideration and are not before us
on appeal.
3 Liu, US 2008/0121862 Al, published May 29, 2008 ("Liu").
4 Datta et al., US 2005/0237850 Al, published Oct. 27, 2005 ("Datta").
5 Our decision refers to the Final Office Action (Final Act.) mailed April 8, 2013,
Appellants' Appeal Brief (Appeal Br.) filed October 8, 2013, the Examiner's
Appeal2014-003822
Application 13/270,592
STATEMENT OF THE CASE
The subject matter on appeal relates to methods of interacting with a
resistive memory (see, e.g., claim 1 ). Appellants disclose that conventional
memory cells are vertically fabricated, which generates topological height
differences, an undesirable result in the fabrication of circuits. Spec. i-fi-14--5.
Appellants disclose a memory cell including a resistive memory element coupled
to a fin of a multi gate field effect transistor select device. Spec. i-f 16. The multi
gate field effect transistor select device and the memory element are arranged in a
lateral manner, which provides a small programmable volume and avoids height
differences. Spec. i120.
Claim 1 is illustrative:
1. A method of interacting with a resistive memory, the method
compnsmg:
controlling current through a fin or multiple connected fins of a
multi gate field effect transistor; and
interacting with a programmable volume portion of a resistive
memory element abutting an end of the fin.
Claims Appendix at Appeal Br. 8.
ANALYSIS
Rejection of Claims 1-9, 11, and 12 over Liu and Datta
The dispositive issue on appeal for claim 1 is whether there would have been
a reason to modify the field effect transistor of Liu to use the multi gate field effect
transistor of Datta.
Answer (Ans.) mailed December 10, 2013, and Appellants' Reply Brief (Reply
Br.) filed February 10, 2014.
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Appeal2014-003822
Application 13/270,592
The Examiner finds Liu discloses a method of interacting with a resistive
memory comprising controlling current through a fin or multiple connected fins of
a field effect transistor and interacting with a programmable volume portion of a
resistive memory element. Final Act. 3. The Examiner finds Liu does not disclose
a multi gate field effect transistor. Id. The Examiner finds Datta discloses
controlling current through a fin of a multi gate field effect transistor for the
purpose of improving stability. Id. The Examiner concludes it would have been
obvious to use the multi gate field effect transistor of Datta in the method of Liu to
improve stability. Id.
Appellants contend there would have been no reason to modify Liu in view
of Datta because the modification would have rendered Liu unsatisfactory for its
intended purpose. Appeal Br. 4--5 and Reply Br. 2-3. In particular, Appellants
assert Datta uses high drive currents in non-planar tri-gate transistors to improve
the stability of a memory cell. Appeal Br. 5 and Reply Br. 3. Appellants contend
Liu addresses a problem of drive currents decreasing, due to the size of memory
cells decreasing, by tapering an electrode to increase current density at an
amorphous region of the phase change material of a memory cell. Appeal Br. 5
and Reply Br. 3--4. Appellants assert "the intended purpose of Liu is to provide
sufficient energy to the phase change region without having to increase drive
current." Appeal Br. 5. In view of this, Appellants argue the solution disclosed by
Datta is not applicable to Liu and modifying Liu in view of Datta would frustrate
the intended purpose of Liu or render Liu inoperable. Appeal Br. 5-6.
Appellants' arguments fail to persuade us the Examiner reversibly erred.
Appellants have not demonstrated, either via evidence or technical reasoning that
using higher drive currents for transistors would render the method of Liu
unsatisfactory for its intended purpose or otherwise conflict with the problem Liu
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Appeal2014-003822
Application 13/270,592
is directed to. Datta discloses using higher drive currents for transistors to improve
the stability of memory cells. Datta i-f 23. Appellants argue the use of the higher
drive currents would conflict with Liu's desire for lower currents, but this is not the
problem addressed by Liu.
Liu states that as memory cell sizes decrease, currents and the durations of
applied currents decrease. Liu i-f 11. However, the statement cited by Appellants is
in the context of a general discussion of the magnitude and duration of currents
used to make the phase change material of a memory cell change between
crystalline and amorphous phases. Id. The citations to the disclosure of Liu made
by Appellants do not demonstrate Liu considered reduced drive currents to be the
problem, as asserted by Appellants.
The problem addressed by Liu is the occurrence of an amorphous region
within the phase change material at a location separate from the electrode used to
change the phase change material between amorphous and crystalline states. Liu i-f
8. Liu discloses this occurs because the hottest region produced by the electrode is
located within the phase change material, away from an interface between the
electrode and the phase change material. Id. Liu discloses that, when the
amorphous region is located away from the interface, a memory cell will remain in
a low resistance memory state and the phase change material cannot be converted
back to a high resistance memory state. Id. To address this problem, Liu discloses
the use of a tapered electrode having its smallest cross-sectional area and highest
resistivity closest to the phase change material so heat generated by the tapered
electrode is close to the interface between the electrode and phase change material,
which prevents the separation of the amorphous region from the electrode. Liu i-fi-1
29, 30, 36, and 48. Thus, Liu is directed to a different problem than the problem
asserted by Appellants.
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Appeal2014-003822
Application 13/270,592
Appellants have not shown, by evidence in the record or persuasive
argument, that the use of higher drive currents would interfere with Liu's goal of
preventing the separation of an amorphous region in a phase change material from
the electrode effecting phase changes in the phase change material. For example,
Appellants do not direct our attention to any citation in Liu to support the argument
that "the intended purpose of Liu is to provide sufficient energy to the phase
change region without having to increase drive current." Appeal Br. 5. To the
contrary, as discussed above, Liu is concerned with preventing the separation of an
amorphous portion of a phase change material from the electrode effecting the
phase changes of the phase change material.
Moreover, the disclosure of Datta provides a reason to modify the transistor
of Liu to use the multi gate field effect transistor of Datta. The Examiner finds
Datta discloses a multi gate field effect transistor provides improved stability and
concludes it would have been obvious to modify the transistor of Liu in view of
Datta. Ans. 2-3. Appellants fail to show that the use of Datta's multi gate field
effect transistor would not reasonably improve stability in Liu's process.
Therefore, Appellants have not met their burden of providing persuasive
argument or evidence to rebut the Examiner's prima facie case of unpatentability.
Appellants do not provide separate arguments for claims 2-9, 11, and 12, which
depend from claim 1.
For the reasons discussed above and for the reasons expressed in the Final
Office Action and the Answer, the§ 103 rejection of claims 1-9, 11, and 12 over
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Appeal2014-003822
Application 13/270,592
the combination of Liu and Datta is sustained.
Rejection of Claim 10 over Liu and Datta
Claim 10 depends from claim 1 and further recites "wherein the multi gate
field effect transistor and the programmable volume portion are laterally disposed
from one another."
In the rejection of claim 10 over Liu and Datta, the Examiner finds Liu
discloses a lateral disposition of a transistor and programmable volume portion of a
resistive memory element. Final Act 5---6.
Appellants argue Figure 10 of Liu depicts a schematic representation of
memory cell and access transistors without disclosing device geometry and layout
of the memory cells and transistors with respect to one another. Appeal Br. 6 and
Reply Br. 4--5.
Appellants' arguments are persuasive. "[T]he examiner bears the initial
burden, on review of the prior art or on any other ground, of presenting a prima
facie case ofunpatentability." In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992).
Figure 10 of Liu does not support the Examiner's finding that Liu discloses a
lateral disposition because, as Appellants argue, Figure 10 depicts a schematic,
rather than a spatial, arrangement for a transistor and a programmable volume
portion of a resistive memory element. In the Examiner's Answer, the Examiner
finds the Merriam-Webster Dictionary defines "lateral" as "of or relating to the
side." The Merriam-Webster definition of "lateral" does not provide any support
for the Examiner's finding because Figure 10 does not depict a transistor and
memory element side by side with one another or in any particular spatial
arrangement. Instead, the Merriam-Webster definition demonstrates the prior art
should disclose or suggest a multi gate field effect transistor and the programmable
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Application 13/270,592
volume portion of a resistive memory element side by side with one another in
order to disclose a lateral disposition between the transistor and the programmable
volume portion. On this record, the Examiner has failed to show Liu's Figure 10
depicts such an orientation. Therefore, the Examiner did not meet the initial
burden of setting forth a prima facie case of unpatentability.
For the reasons described above, we do not sustain the Examiner's§ 103(a)
rejection of claim 10 over the combination of Liu and Datta.
DECISION
On the record before us:
A. the Examiner's rejection of claims 1-9, 11, and 12 under 35 U.S.C. §
103(a) as unpatentable over the combination of Liu and Datta is affirmed; and
B. the Examiner's rejection of claim 10 under 35 U.S.C. § 103(a) as
unpatentable over the combination of Liu and Datta is reversed.
No time period for taking any subsequent action in connection with this
appeal may be extended under 37 C.F.R. § 1.136(a)(l ).
AFFIRMED-IN-PART
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