Ex Parte Kim

Board of Patent Appeals and Interferences

May 29, 2008

10382560 (B.P.A.I. May. 29, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte HYEON-SEAG KIM
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Appeal 2007-3980
Application 10/382,560
Technology Center 2800
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Decided: May 29, 2008
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Before MICHAEL R. FLEMING, Chief Administrative Patent Judge,
KENNETH W. HAIRSTON, ALLEN R. MACDONALD, LINDA E.
HORNER, and SCOTT R. BOALICK, Administrative Patent Judges.

MACDONALD, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2007-3980
Application 10/382,560

STATEMENT OF CASE
Introduction
Appellant appeals under 35 U.S.C. § 134 from a final rejection of
claims 1, 3, 5, 7-9, 11, 13, and 21. We have jurisdiction under 35 U.S.C.
§ 6(b).
According to Appellant, the invention relates to interconnect
structures in semiconductor devices. (Spec. 1:6-7).
Exemplary Claim
Exemplary independent claim 1 under appeal reads as follows:
Claim 1: An interconnect structure comprising:
a) a top interconnect metal layer;
b) at least one via electrically connected to said top interconnect metal
layer;
c) a bottom interconnect metal layer having at least one finger and a
bottom layer width,
i) wherein said at least one via is electrically connected to said
at least one finger,
ii) wherein said at least one finger has a finger width less than
said bottom layer width and substantially equal to a
minimum design rule width,
iii) wherein said at least one finger does not cause said bottom
layer width to increase, and
iv) wherein a width ratio of said finger width to a width of said
at least one via is reduced,
v) wherein a plurality of fingers have a plurality of associated
finger widths, and
vi) wherein a combined finger width of said plurality of
associated finger widths is less than said bottom layer width.
(Paragraph lettering and some formatting added).
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Prior Art
The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Kinoshita EP 0845808 A2 June 3, 1998
Rejections
The Examiner rejected claims 1, 3, 5, 7-9, 11, 13, and 21 under
35 U.S.C. § 112, second paragraph, as being indefinite (Ans. 3).
The Examiner rejected claims 1, 3, 5, 7-9, 11, 13, and 21 under
35 U.S.C. § 102(b) as being anticipated by Kinoshita (Ans. 4-6).1
Appellant’s Contentions
Appellant contends that claims 1, 3, 5, 7-9, 11, 13, and 21 are not
indefinite and that the Examiner erred in rejecting these claims because:
By specifying that the finger width of the at least one finger is
substantially equal to a minimum design rule, it is reasonably assumed
that a via that is connected to a finger having a finger width that is
substantially equal to a minimum design rule width would not have a
substantially narrower width compared to a via that is connected to a
wider finger. Thus, by specifying that the finger width of the at least
one finger is substantially equal to a minimum design rule, a reduction
in the width ratio (i.e., an effective ratio) of finger width to via width
(i.e. the width of the at least one via) is achieved compared to an
implied interconnect structure that does not include at least one finger
having a finger width that is substantially equal to a minimum design
rule width.
(App. Br. 6-7) (emphasis added).

1 The Examiner’s rejection mistakenly lists claim 12, which Appellant
indicates has been cancelled (App. Br. 2), as being rejected.
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Application 10/382,560

Examiner’s Findings or Conclusions
The Examiner concluded that claims 1, 3, 5, 7-9, 11, 13, and 21 are
indefinite because the limitation “wherein a width ratio of the finger width to
a width of the at least one via is reduced” is indefinite. (Ans. 3.) The
Examiner found that “the claims have not set a specific or initial ‘width
ratio’ so that the width ratio of the finger/via is reduced.” Id.
In support of this conclusion the Examiner reasoned at page 7 of the
Answer as follows:
Assuming: Wf is the finger width and Wv is the via
width, the width ratio Rw= Wf/Wv. The term “is reduced”
indicate[s] a state of the ratio Rw being changed from larger to
smaller.
The claims however, [do] not indicate what is the initial
ratio R so that the Rw can be reduced [as compared to an initial
ratio R]. This is critical to one having ordinary skill in the art
because [a] worker in the art should be able to determine a ratio
reduction base[d] on some other ratio.

Result
We affirm.

ISSUE(S)
Has Appellant established that the Examiner erred in rejecting claims
1, 3, 5, 7-9, 11, 13, and 21 under 35 U.S.C. § 112, second paragraph, as
being indefinite?

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Application 10/382,560

FINDINGS OF FACT
The following Findings of Fact (FF) are shown by a preponderance of
the evidence.
Appellant’s Admitted Prior Art
1. “Figure 1A shows a top view of conventional interconnect
structure 100 in a semiconductor die” (Spec. 5:13-14).
2. “As shown in Figure lA, interconnect structure 100 includes
bottom interconnect metal (‘ICM’) layer 112, vias 130 and 140 and top ICM
layer 120” (Spec. 5:14-16).
3. “Width 160 of bottom ICM layer 112 is much greater than
width 161 of via 130 . . .” (Spec. 5:20-21.)

Appellant’s Invention
4. Appellant indicates that:
Figure 3D shows interconnect structure 310[,] formed in
accordance with one embodiment of the present invention. As
shown in Figure 3D, structure 310 includes top ICM layer 320,
vias 332, 334, 336, 342, 344 and 346 and bottom ICM layer
312, where bottom ICM layer 312 comprises fingers 372, 374,
376, 382, 384 and 386. Bottom ICM layer 312 is electrically
connected to top ICM layer 320 by vias 332, 334, 336, 342, 344
and 346. Specifically, fingers 372, 374, 376, 382, 384 and 386
are connected to vias 332, 334, 336, 342, 344 and 346,
respectively.
(Spec. 8:7-13.)
5. “The present invention advantageously increases stress
migration reliability by reducing the effective ratio of the width of the
bottom ICM layer to via width, while substantially retaining the overall ICM
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layer width to preserve its low resistance and its high current conduction
capability.” (Spec. 8:14-17.)
6. “Referring to Figure 3D, bottom ICM layer 312 has bottom
layer width 360. Fingers 372, 374 and 376 have finger widths 362, 364 and
366, respectively. Finger widths 362, 364 and 366 are each equal to slightly
less than approximately one-third of bottom layer width 360.” (Spec.
8:17-20.)
7. “Moreover, a substantial portion of bottom ICM layer 312 has
preserved its initial configuration, i.e. a substantial portion of bottom ICM
layer 312 is not divided into fingers. However, the effective width of bottom
ICM layer 312 in relation to via 332 is approximately equal to finger width
362.” (Spec. 8:20-9:2.)
8. “Moreover, the effective ratio of the width of bottom ICM layer
312, e.g. finger width 362, to via width, e.g. width of via 332, is significantly
reduced, while approximately retaining the overall bottom ICM layer width
because the sum of finger widths 362, 364 and 366 is approximately equal to
bottom layer width 360.” (Spec. 9:2-5.)
9. “In comparison to the conventional interconnect structure 100
of Figure lA, the embodiment of the present invention of Figure 3D, reduces
the effective ratio of the width of bottom ICM layer 312, e.g. finger width
362, to a via width, e.g. widths of vias 362, 364 and 366, to approximately
one-third of the ratio of bottom layer width 160 to via width 161.” (Spec.
9:9-13.)
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10. “This reduction in the effective ratio of bottom layer width to
via width advantageously increases stress migration reliability, which
reduces void migration underneath vias.” (Spec. 9:13-15.)
11. “In sum, forming interconnect structures in the manner
described above advantageously results in an ICM layer comprising fingers,
which reduces the effective ratio of bottom layer width to via width.” (Spec.
9:16-18.)

PRINCIPLES OF LAW
Appellant has the burden on appeal to the Board to demonstrate error
in the Examiner’s position. See In re Kahn, 441 F.3d 977, 985-86 (Fed. Cir.
2006).
Claim Construction
“Claims must be read in view of the specification, of which they are a
part.” Markman v. Westview Instruments, Inc., 52 F.3d 967, 979 (Fed. Cir.
1995) (en banc). “[D]uring examination proceedings, claims are given their
broadest reasonable interpretation consistent with the specification.” In re
Hyatt, 211 F.3d 1367, 1372 (Fed. Cir. 2000). “Moreover, limitations are not
to be read into the claims from the specification.” In re Van Geuns, 988
F.2d 1181, 1184 (Fed. Cir. 1993) (citing In re Zletz, 893 F.2d 319, 321 (Fed.
Cir. 1989)).

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Application 10/382,560

ANALYSIS
(A)
35 U.S.C. § 112, Second Paragraph
Appellant argues that the Examiner has erred because, as set forth in
“Appellant’s Contentions” supra, “claims 1, 3, 5, 7-9, 11, 13, and 21 meet
the requirements of 35 U.S.C. § 112, second paragraph.” (App. Br. 7.)
We disagree. Juxtaposed to the Examiner’s reasoning that there must
be an “initial ratio R” (i.e., some initial baseline ratio) for purposes of
comparison is Appellant’s contention that “it is reasonably assumed that a
via [v1] that is connected to a finger [f1] having a finger width that is
substantially equal to a minimum design rule width would not have a
substantially narrower width compared to a via [v2] that is connected to a
wider finger [f2].” (Emphasis added.) However, Appellant presents no
factual basis for this assumption. Also, the assumption hinges on a
requirement that the widths of v1 and v2 be similar (not substantially
narrower). We find no rational basis for this. To the contrary, as much as
the width of f2 is greater compared to the width of f1, we see no reason that
the width of v2 cannot also be greater as compared to the width of v1. Thus,
under such a condition, the “width ratio” would be held constant, rather than
being reduced by going from a wider finger f2 to a narrower finger f1.
The second part of Appellant’s contention that “a reduction in the
width ratio (i.e., an effective ratio) of finger width to via width (i.e. the width
of the at least one via) is achieved compared to an implied interconnect
structure that does not include at least one finger having a finger width that
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Application 10/382,560

is substantially equal to a minimum design rule width” fails for the same
reason discussed above.
We also note that Appellant’s Specification is quite specific that the
reduction of the ratio of the finger width to via width is in comparison to the
conventional interconnect structure 100 of the prior art (See FF 1-3, and 9)
(i.e., the prior art forms the baseline), not in comparison to some implied
interconnect structure. Further, it appears that Appellant’s disclosed
invention hinges on a requirement that the width of a via in the invention be
similar to the width of a via in the prior art (FF 3) (what Appellant phrases in
their arguments as not substantially narrower). Yet both the Specification
and claims are silent as to this requirement. It is clear to us from Appellant’s
argument that they had something in mind with respect to the vias that we do
not find conveyed by the language of the claim. Without some guidance to
the artisan about the baseline ratio (what the Examiner terms as the “initial
ratio R”) to which the claimed “width ratio” is being compared, we agree
with the Examiner that the claim is indefinite.
Therefore, for the reasons above, Appellant has not established that
the Examiner erred with respect to this rejection of claims 1, 3, 5, 7-9, 11,
13, and 21 under § 112, second paragraph.
(B)
35 U.S.C. § 102
We do not reach the merits of the Examiner's rejection under
35 U.S.C. § 102 or the merits of the Kinoshita reference at this time. Rather,
we reverse pro forma the outstanding rejection under 35 U.S.C. § 102
because the appealed claims fail to satisfy the requirements of the second
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paragraph of 35 U.S.C. § 112. Before a proper review of the prior art
rejection can be performed, the subject matter encompassed by the claims on
appeal must be reasonably understood without resort to speculation.
Presently, speculation and conjecture must be utilized by us and by
the artisan inasmuch as the claims on appeal do not adequately reflect what
the disclosed invention is under the second paragraph of 35 U.S.C. § 112.
See In re Steele, 305 F.2d 859, 862 (CCPA 1962) (A prior art rejection
cannot be sustained if the hypothetical person of ordinary skill in the art
would have to make speculative assumptions concerning the meaning of
claim language.); See also In re Wilson, 424 F.2d 1382, 1385 (CCPA 1970)
(“If no reasonably definite meaning can be ascribed to certain terms in the
claim, the subject matter does not become obvious-the claim becomes
indefinite.”).

CONCLUSIONS OF LAW
(1) Appellant has failed to establish that the Examiner erred in
rejecting claims 1, 3, 5, 7-9, 11, 13, and 21 as being unpatentable under
35 U.S.C. § 112, second paragraph, as being indefinite.
(2) Claims 1, 3, 5, 7-9, 11, 13, and 21 are not patentable.

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DECISION
The Examiner’s rejection of claims 1, 3, 5, 7-9, 11, 13, and 21 under
35 U.S.C. § 112, second paragraph, is affirmed.
The Examiner’s rejection of claims 1, 3, 5, 7-9, 11, 13, and 21 under
35 U.S.C. § 102 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)(1)(iv).

AFFIRMED

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