Ex Parte Hsiao

Board of Patent Appeals and Interferences

Sep 29, 2003

09837943 (B.P.A.I. Sep. 29, 2003)

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The opinion in support of the decision being entered
today was not written for publication in a law journal
and is not binding precedent of the Board.
Paper No. 15
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte TIEN-EN HSIAO

Appeal No. 2003-1884
Application No. 09/837,943

ON BRIEF

Before KIMLIN, GARRIS and WALTZ, Administrative Patent Judges.
KIMLIN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the final rejection of claims 1-25,
all the claims in the present application. Claim 1 is
illustrative:
1. A cooling system for supplying a reaction chamber with
coolant during a semiconductor fabrication process; said cooling
system comprising:
coolant supply circuitry which controls supply of said
coolant;
a coolant flow controller having a setpoint control to set a
flow of said coolant by transmitting a voltage signal to said
circuitry; and
Appeal No. 2003-1884
Application No. 09/837,943
1 We rely upon full English translations of Tsubone,
Nakagawa, and Matsumura, all previously made of record.
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a filter for removing noise from said voltage signal to
stabilize said flow of said coolant.
The examiner relies upon the following references as
evidence of obviousness:
Tsubone et al. (Tsubone) Hei 5-49904 Mar. 02, 1993
(Japanese Kokai Patent Application)
Nakagawa Hei 7-161696 Jun. 23, 1995
(Japanese Kokai Patent Application)
Matsumura Hei 11-284016 Oct. 15, 1999
(Japanese Kokai Patent Application)1
Ralph J. Smith, Circuits, Devices, and Systems- A First Course in
Electrical Engineering 158-61, 511-13 (3d ed., John Wiley & Sons,
Inc., New York 1966)
MKS Product Announcement (May 25, 1999)
Appellant's claimed invention is directed to a cooling
system for a reaction chamber used in a semiconductor fabrication
process. The system comprises a coolant flow controller having a
setpoint control to set a flow of the coolant by transmitting a
voltage signal to coolant supply circuitry. The system also
comprises a filter for removing noise from the voltage signal.
The removal of noise by the filter allows for a stable flow of
coolant which results in uniform contact between a semiconductor
wafer and its supporting chuck.
Appeal No. 2003-1884
Application No. 09/837,943
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Appealed claims 1-13, 15-17, 20-23 and 25 stand rejected
under 35 U.S.C. § 103 as being unpatentable over Tsubone in view
of Smith and MKS. Claims 14 and 24 stand rejected under
35 U.S.C. § 103 as being unpatentable over the stated combination
of references further in view of Nakagawa. Also, claims 18 and
19 stand rejected under 35 U.S.C. § 103 as being unpatentable
over the stated combination of references further in view of
Matsumura.
We have thoroughly reviewed the respective positions
advanced by appellant and the examiner. In so doing, we find
ourselves in agreement with appellant that the examiner has not
established a prima facie case of obviousness for the claimed
subject matter. Accordingly, we will not sustain the examiner's
rejection.
Appellant agrees with the examiner that one of ordinary
skill in the art would have known to use a filter for removing
noise from an electronic circuit. It is appellant's contention
that the present invention resides in the discovery that "the
fluctuating mass coolant flow problem results from the spiking
voltage signal at setpoint control 102 [whereas] [p]rior to the
invention, ordinarily skilled artisans did not recognize that the
problem was the spiking voltage control noise" (page 7 of
Appeal No. 2003-1884
Application No. 09/837,943
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principal brief, second paragraph). According to the present
specification,
Those of ordinary skill in the relevant art have
heretofore concluded that noise 12' and 14' is due to
the RF power of the apparatus and the magnetic field
surrounding the cables 134,136 adjacent to the FLOW
terminal 104 and the PRESSURE terminal 106 (Fig. 2).
According to applicant's study, however, neither RF
power nor magnetic influence is the root cause of the
spike problem. Applicant has insulated cables 134,136
with a mass of lead, for example, to prevent inter-
ference by any electrical or magnetic field, but such
measures failed to improve the spike problem [page 11,
first paragraph.
According to the examiner:
As control signals may acquire noise specially
[sic, especially] if routed across several pieces of
active components, as admitted by the applicant
(Specification page 5 line 11-130 [sic, lines 11-13]),
it would have been obvious to one having ordinary skill
in the art at the time the invention was made to reduce
noise by using a simple RC filter connected between the
output of the coolant controller and the input of the
flow controller.
Page 5 of Answer, first paragraph. The examiner further explains
that "[o]nce the noise-affected part of the system is identified,
it would have been a simple matter to reduce noise by using
filtering" (page 7 of Answer, last paragraph).
The flaw in the examiner's reasoning is that although it may
have been a simple matter for one of ordinary skill in the art to
reduce noise by using filtering, the examiner has not established
that one of ordinary skill in the art would have reasonably
Appeal No. 2003-1884
Application No. 09/837,943
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expected that the problem of fluctuating coolant flow is caused
by noise in the voltage signal at the setpoint control. On the
other hand, appellant makes the following compelling argument at
page 3 of the Reply Brief:
Cooling systems involve hydromechanics,
electronics, and mechanics. The reasons for the
coolant mass flow spike problem might include, but not
limited to, coolant characteristics, imperfection of
control circuit design, imperfection of the coolant
transfer parts, malfunction of the control circuit,
miscommunication between the control circuit and the
coolant transfer parts, static electricity, magnetic
field, RF power, temperature, dust, etc. As described
in the present application, at the time the invention
was made, ordinarily skilled artisans linked the
coolant mass flow spike problem to control circuit
malfunction, the magnetic field surrounding cables 134
and 136, and RF power [paragraph three].
In our view, while appellant's solution to the problem may
have been obvious to one of ordinary skill in the art, the
examiner has not demonstrated that appellant's recognition of the
problem would have been obvious to one of ordinary skill in the
art. It is well settled that invention may reside in the
discovery of a problem even when its solution becomes readily
apparent once the problem is identified.
Appeal No. 2003-1884
Application No. 09/837,943
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In conclusion, based on the foregoing, the examiner's
decision rejecting the appealed claims is reversed.
REVERSED
EDWARD C. KIMLIN )
Administrative Patent Judge )
)
)
)
)
BRADLEY R. GARRIS ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
)
THOMAS A. WALTZ )
Administrative Patent Judge )
ECK:clm
Appeal No. 2003-1884
Application No. 09/837,943
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Applied Materials, Inc.
2881 Scott Blvd., M/S 2061
Santa Clara, CA 95050