Ex Parte Kang et al

Patent Trial and Appeal Board

Jul 31, 2013

11657000 (P.T.A.B. Jul. 31, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
11/657,000 01/23/2007 Sung Kwon Kang YOR920030273US1
(01400.00
2966
7590 08/01/2013
The Law Offices of Robert J. Eichelburg
HODAFEL Building, Suite 200
196 Acton Road
Annapolis, MD 21403
EXAMINER
SNOW, COLLEEN ERIN
ART UNIT PAPER NUMBER
2813
MAIL DATE DELIVERY MODE
08/01/2013 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte SUNG KWON KANG, DA-YUAN SHIH, and
YOON-CHUL SON1
____________

Appeal 2011-006367
Application 11/657,0002
Technology Center 2800
____________

Before BRIAN J. McNAMARA, SCOTT E. KAMHOLZ, and
JAMES B. ARPIN, Administrative Patent Judges.

ARPIN, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s
rejection of claim 15. Claims 1-14 are cancelled. App. Br. 2.3 We have
jurisdiction under 35 U.S.C. § 6(b). We reverse.

1 International Business Machines Corporation is the real party-in-interest.
2 This application is a parent application to U.S. Patent Application No.
12/173,803 that currently is under appeal, i.e., Appeal No. 2011-008660,
before this same panel of the Board.
Appeal 2011-006367
Application 11/657,000

2
INVENTION
Appellants’ invention relates to processes for inhibiting intermetallic
inclusions in the fabrication of integrated circuit interconnection structures.
See generally Spec. 1:7-10. In particular, such processes comprise providing
stacked layers on the integrated circuit comprising a first layer of electroless
nickel-phosphorus (Ni(P)), a second layer of tin (Sn) or copper (Cu), and a
third layer of a Sn rich, lead (Pb) free solder. Id. at 4:1-4; 7:18-22. The
layers then are heated to fuse them together. Id. at Figs. 5, 6.
Claim 15 is reproduced below with line breaks and spacing added for
clarity:
15. A process for inhibiting intermetallic inclusions in the
fabrication of integrated circuit interconnection structures,
comprising
providing stacked layers on said integrated circuit
comprising
as a first layer an electroless Ni(P) coating, and
as a second layer, a metal selected from Sn or Cu,
and
as a third layer, a Sn rich Pb-free solder and
subjecting said stacked layers to a fusion temperature
excursion to fuse said stacked layers together and
wherein said second layer ranges in thickness from 0.1 to
5.0 microns and
said third layer is a material from the group Sn, Sn-
3.5%Ag, Sn-0.7%Cu, Sn-3%Bi, Sn-3.5%-0.7%Cu, Sn-3.5%Ag-
3%Bi, Sn-8%- Zn-3%Bi, Sn-3.5%Ag-0.7%Cu-0.5%Sb, Sn-
2.5%Ag-0.5%Cu.

The Examiner relies on the following as evidence of unpatentability:

3 Throughout this opinion, we refer to (1) the Appeal Brief (App. Br.) filed
July 20, 2010; (2) the Examiner’s Answer (Ans.) mailed November 22,
2010; and (3) the Reply Brief (Reply Br.) filed December 22, 2010.
Appeal 2011-006367
Application 11/657,000

3
Sakuyama
Copeland
Kim
US 2003/0096494 A1
US 6,596,621 B1
US 6,716,738 B2
May 22, 2003
July 22, 2003
Apr. 6, 2004

THE REJECTION
The Examiner rejected claim 15 under 35 U.S.C. § 103(a) as
unpatentable over Sakuyama, Copeland, and Kim. Ans. 3-5.

OBVIOUSNESS REJECTION OVER SAKUYAMA, COPELAND,
AND KIM
Regarding claim 15, the Examiner finds that Sakuyama discloses all
of the limitations of the claimed processes, except that Sakuyama does not
disclose that the second layer is selected from Sn or Cu, that the second layer
has a thickness in a range of 0.1 to 5.0 microns, or that the third layer is one
of the compositions specified in the claim. Ans. 3-4. Nevertheless, the
Examiner finds that Copeland discloses a solder preparation in which the
second layer is Cu and may have a thickness of 0.3 microns, i.e., within the
range recited in claim 15. Id. at 4. Further, the Examiner finds that Kim
discloses a Sn-3.5%Ag solder, which is among those recited in claim 15. Id.
at 4-5. Moreover, the Examiner concludes that a person of ordinary skill in
the relevant art would have reason to modify the teachings of Sakuyama in
view of those of Copeland and Kim to achieve the processes recited in claim
15. Id.
Appellants argue that the combined references fail to teach or suggest
all of the limitations of processes, as recited in claim 15, and that the
Examiner fails to demonstrate that a person of ordinary skill in the relevant
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Application 11/657,000

4
art would have reason to combine the teachings of Sakuyama, Copeland, and
Kim to achieve the processes recited in claim 15. App. Br. 3-13.
ISSUES
(1) Under § 103(a), has the Examiner erred by finding that Sakuyama,
Copeland, and Kim, collectively, teach or suggest “a second layer, a metal
selected from Sn or Cu,” as recited in claim 15?
(2) Is the Examiner’s combination of the teachings of these
references supported by articulated reasoning with some rational
underpinning to justify the Examiner’s obviousness conclusion?
ANALYSIS
We agree with the Examiner’s findings that Sakuyama discloses all of
the limitations of claim 15, except for the composition and thickness of the
second layer. Instead, Sakuyama discloses a second layer of gold (Au) or
palladium (Pd). Sakuyama ¶ [0053].
With regard to the second layer, the Examiner finds that Copeland
discloses a first layer of Ni, a second layer of Cu, and a third layer of Sn or
silver (Ag). Ans. 4 (citing Copeland, col. 2, ll. 32-47). Copeland explains
that “depositing the Cu layer prior to the Sn/Ag layer (or separate Sn and Ag
layers) enhances the protection of the Ni barrier layer during solder reflow.”
Copeland, col. 5, ll. 1-3 (emphasis added); see Ans. 4. The Examiner
concludes that a person of ordinary skill in the art would have had reason to
replace Sakuyama’s Au or Pd layer with Copeland’s Cu layer in order to
obtain the benefits of a Cu layer that Copeland identifies. Ans. 5.
The Examiner acknowledges that the disclosure cited in Copeland
addresses the benefits of protecting a Ni layer, not the Ni(P) layer claimed.
See Ans. 6. The Examiner instead contends that “there is no reason to
Appeal 2011-006367
Application 11/657,000

5
believe, nor do the Appellants appear to be asserting, that the presence of
phosphorus in the nickel layer would negate the beneficial effects of the Cu
material as disclosed by [Copeland].” Id.
Appellants argue that the Examiner has not shown that Copeland’s
suggestion of employing Cu as the second layer is relevant to the claimed
subject matter, because the benefits that the Cu layer supposedly provides
relate to a Ni layer, not a Ni(P) layer. App. Br. 7-8; Reply Br. 2-4. In
particular, Appellants argue that the Examiner has placed the burden
improperly on Appellants to show that Copeland is irrelevant to the claimed
subject matter. Reply Br. 4.
We agree with Appellants on this point. Although the Examiner
correctly found that Copeland discloses a Cu layer, such as that recited in
claim 15, we are not persuaded that the Examiner has demonstrated that a
person of ordinary skill in the art would have a reason to combine the
teachings of Sakuyama and Copeland in the manner proposed by the
Examiner to achieve the claimed invention.
In rejecting a claim under § 103(a), the Examiner must establish a
factual basis to support the legal conclusion of obviousness. See In re Fine,
837 F.2d 1071, 1073 (Fed. Cir. 1988). In so doing, the Examiner must make
the factual determinations set forth in Graham v. John Deere Co., 383 U.S.
1, 17 (1966) (noting that § 103(a) leads to three basic factual inquiries: (1)
the scope and content of the prior art; (2) the differences between the prior
art and the claims at issue; and (3) the level of ordinary skill in the art).
Further, the Examiner’s obviousness rejection must be based on
“some articulated reasoning with some rational underpinning to
support the legal conclusion of obviousness” . . . . [H]owever,
the analysis need not seek out precise teachings directed to the
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Application 11/657,000

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specific subject matter of the challenged claim, for a court can
take account of the inferences and creative steps that a person
of ordinary skill in the art would employ.

KSR Int’l. Co. v. Teleflex, Inc., 550 U.S. 398, 418 (2007) (quoting In re
Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006)).
If the Examiner’s burden is met, the burden then shifts to the
appellant to overcome the prima facie case with argument and/or evidence.
Obviousness then is determined on the basis of the evidence as a whole
and/or the relative persuasiveness of the arguments. See In re Oetiker, 977
F.2d 1443, 1445 (Fed. Cir. 1992).
Here, the Examiner’s contention that “there is no reason to believe . . .
that the presence of phosphorus in the nickel layer would negate the
beneficial effects of the Cu” is unsupported by objective findings of fact and
is, therefore, an inadequate rational underpinning to justify the Examiner’s
obviousness conclusion. Instead, the Examiner must make the appropriate
factual determinations in the support of the obviousness rejection.
As Appellants explain in their Specification, the Ni will combine
chemically with the P under the claimed reaction conditions. Spec. 2:7-27.
Thus, the P is chemically active, and its presence reasonably may be
expected to affect how the Cu interacts with the Ni, absent evidence to the
contrary. Consequently, it is not at all clear from the record before us that
the presence of P in the Ni(P) is so insignificant as to have no effect on the
benefits from using Cu as the second layer.
The Examiner may not rely on a lack of evidence that Copeland’s Cu
layer would not achieve the same or similar benefits when applied to a Ni(P)
layer or a Ni layer, as a rationale for replacing Sakuyama’s Au or Pd layer
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Application 11/657,000

7
with Copeland’s Cu layer. Ans. 6; see also Reply Br. 4. Therefore, we
conclude that the Examiner’s combination of the teachings of the Sakuyama
and Copeland is not supported by articulated reasoning with some rational
underpinning to justify the Examiner’s obviousness conclusion and that the
Examiner has failed to establish a prima facie case for obviousness.
For the foregoing reason, we are persuaded of error in the rejection of
independent claim 15. Therefore, we do not sustain the rejection of claim
15.
CONCLUSION
The Examiner erred in rejecting claim 15 under § 103(a).

DECISION
The Examiner’s decision rejecting claim 15 is reversed.

REVERSED

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