Ex Parte Wu et al

Patent Trial and Appeal Board

Feb 26, 2014

11773171 (P.T.A.B. Feb. 26, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte WENG-JIN WU, KU-FENG YANG, HUNG-PIN CHANG,
WEN-CHIH CHIOU, and CHEN-HUA YU
____________

Appeal 2011-011883
Application 11/773,171
Technology Center 2800
____________

Before BRADLEY R. GARRIS, TERRY J. OWENS, and
BEVERLY A. FRANKLIN, Administrative Patent Judges.

PER CURIAM.

DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134 from the Examiner’s
decision rejecting claims 1-3, 5, 18-21, and 32-34. We have jurisdiction
over the appeal pursuant to 35 U.S.C. § 6(b).
We AFFIRM.

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Application 11/773,171

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Claim 1 is representative of the subject matter on appeal and is set
forth below:
A method comprising:
grinding away substrate material from a backside of a semiconductor
device;
detecting a current change in a grinding device responsive to exposure
of a first set of vias through said substrate material, wherein said grinding is
stopped responsive to said detected current change;
polishing away an additional amount of said substrate material; and
monitoring exposure of one or more additional sets of vias through
said substrate material to determine said additional amount, wherein said one
or more additional sets of vias are located in said semiconductor device at a
known depth different than said first set.

The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Sawada et al. US 6,930,382 B2 Aug. 16, 2005
Boyd et al. US 7,090,562 B1 Aug. 15, 2006
Shida et al. US 2004/0237413 A1 Dec. 2, 2004

THE REJECTIONS
1. Claims 1, 2, 5, and 18-20 are rejected under 35 U.S.C. § 103(a) as
being unpatentable over the Sawada in view of Boyd.
2. Claims 3, 21, and 32-34 are rejected under 35 U.S.C. § 103(a) as
being unpatentable over the Sawada in view of Boyd, and further in view of
Shida.
ANALYSIS

As an initial matter, Appellants argues the patentability of claims 1,
18 and 32 in a similar fashion regarding the subject matter of detecting
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current change responsive to exposure of a via through a substrate. We
select claim 1 as representative of this argued subject matter. Accordingly,
we confine our discussion to appealed claim 1 which contains limitations
representative of the arguments made by Appellants pursuant to 37 C.F.R. §
41.37(c)(1)(vii).
We sustain the above rejections based on the findings of fact,
conclusions of law, and rebuttals to arguments expressed by the Examiner in
the Answer. We add the following for emphasis.
Appellants argue that:
The Examiner incorrectly concludes that Sawada inherently
discloses “monitoring exposure of one or more additional sets
of vias through said substrate material to determine said
additional amount.” The Examiner continues to assert the
reasoning that “[e]ven the monitoring of the time needed for the
polishing process to expose the via would be considered to be
the monitoring of the exposure of the vias based on the time
needed to expose the vias.” Examiner’s Answer p. 12.
Appellants disagree. Although a time may be determined such
that the end of the polishing process results in exposed vias, in
such a process, the time is being monitored and not the
exposure of the vias. Thus, the Examiner’s inherency reasoning
regarding claim 1 fails to satisfy the high inherency standard.
Reply Br. 4-5. See also Br. 20-22.
We agree with the Examiner’s stated position as expressed on page 12
of the Answer, reproduced in part below:
The Examiner’s response is that the Sawada reference does
inherently teach monitoring exposure of one or more additional
sets of vias through the substrate material to determine said
additional amount. Specifically, Sawada teaches “CMP is
carried out until the back surface of the substrate including
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metal plugs 15c and 15d is flatted” (col. 6, lines 46-48) and
shown in figure 2G annotated below. Furthermore, there is no
possible way that the CMP can be carried out until the back
surface of the substrate including metal plugs 15c and 15d is
flatted without monitoring the exposure of the metal plugs/vias.
Appellants do not adequately address the Examiner’s point that “there
is no possible way that the CMP can be carried out until the back surface of
the substrate including metal plugs 15c and 15d is flatted without monitoring
the exposure of the metal plugs/vias.” As such, we are unpersuaded by
Appellants’ arguments in this regard.
Appellants then argue that neither Boyd nor Sawada teaches that the
eddy current type sensor detects a current change responsive to a via
exposed through a substrate material. Br. 22-26. Reply Br. 5-8.
It is the Examiner’s position that:
Sawada does not disclose explicitly detecting a current change
in a grinding device responsive to exposure of a via through the
substrate material, wherein the grinding is stopped responsive
to the detected current.
Nonetheless, Boyd discloses using an eddy current sensor as a
part of a grinding device to determine the end point of the
grinding process (col. 12, lines 4-42).
It would have been obvious to one of ordinary skill in the art at
the time the invention was made to use the method for using the
eddy-current sensor of Boyd for detecting the end point of the
grinding of Sawada since this would help to accurately
determine when to stop grinding.
Ans. 5.
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The Examiner further explains that, as taught by Boyd, those skilled
in the art would understand how an eddy current sensor detects the end point
of a grinding process. Ans. 13. The Examiner states that thus it would have
been obvious to have used such a technique in the grinding process of
Sawada to detect when the grinding becomes closer to the metal plugs 15c
and 15d of Sawada for the reasons stated therein. Id. We agree with the
Examiner’s position. A prima facie case of obviousness is established where
the Examiner demonstrates that the invention is nothing more than the
predictable result of a combination of familiar elements according to known
methods. KSR Int’l. Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007); Rolls-
Royce, PLC v. United Technologies Corp., 603 F.3d 1325, 1338 (Fed. Cir.
2010)(“If a person of ordinary skill, before the time of invention and without
knowledge of that invention, would have found the invention merely an
easily predictable and achievable variation or combination of the prior art,
then the invention likely would have been obvious.”). The Examiner has
made such a case herein.
In view of the above, we affirm Rejection 1. With regard to Rejection
2, we also affirm this rejection based upon similar reasons as discussed
above, and as provided by the Examiner on pages 8-10 and 14-16 of the
Answer (Appellants offer similar arguments that the applied art does not
teach a current change responsive to exposure of a via through substrate
material (Br. 26-29; Reply Br. 6-8)).
The decision of the Examiner is affirmed.
CONCLUSION OF LAW AND DECISION
Each rejection is affirmed.
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No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED

cdc