Ex Parte Thakur et al

Board of Patent Appeals and Interferences

Jan 30, 2009

10121635 (B.P.A.I. Jan. 30, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte RANDHIR THAKUR,
STEVEN VERHAVERBEKE, and J. KELLEY TRUMAN
____________

Appeal 2008-3030
Application 10/121,6351
Technology Center 1700
____________

Decided: 2 January 30, 2009
____________

Before CHUNG K. PAK, ROMULO H. DELMENDO, and
MICHAEL P. COLAIANNI, Administrative Patent Judges.

PAK, Administrative Patent Judge.

1 The subject application is said to be a continuation of U.S. Patent
Application 10/208,142, filed on July 20, 2002. See Spec. 1, Para. [0001].
2 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 CFR § 1.304, begins to run from the decided date
shown on this page of the decision. The time period does not run from the
Mail Date (paper delivery) or Notification Date (electronic delivery).
Appeal 2008-3030
Application 10/121,635

DECISION ON APPEAL
STATEMENT OF THE CASE
This is a decision on an appeal under 35 U.S.C. § 134 from the
Examiner's final rejection of claims 1 through 5, 8, 9, and 39 though 42.
Claims 43 through 56, the other claims pending in the above-identified
application, stand withdrawn from consideration (Br. 3). We have
jurisdiction pursuant to 35 U.S.C. § 6.
The subject matter on appeal is directed to “[a] single wafer cleaning
apparatus” (e.g., Claim 1). The Specification focuses on employing a pair of
nozzles for ejecting fluids having different surface tension characteristics
onto a top surface of a rotating wafer to generate a Marangoni force which
according to Appellants, is known to be employed for removing water from
the surface of the wafer (Spec. 2, para. [0007] and 4, para. [0012]), together
with Fig. 1). Consistent with Appellants’ reliance on wafer processing
conditions, rather than apparatus features, as their invention, the
Specification at page 1, paragraph [0001], states that “[t]he present invention
pertains in general to wafer processing and in particular to a single wafer
cleaning process” (emphasis added). Details of the appealed subject matter
are recited in representative independent claims 1 and 39 reproduced from
the Claims Appendix to the Appeal Brief as follows3:
1. A single wafer cleaning apparatus, comprising:

a rotatable bracket capable of holding a wafer;

3 To the extent that Appellants have presented substantive arguments for
separate patentability of any individual claims on appeal, we will address
them separately consistent with 37 C.F.R. § 41.37(c)(1)(vii) (2005).

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a first fluid having a first surface tension;

a second fluid having a second surface tension lower than the first
surface tension;
a first nozzle positioned to apply the first fluid in a first direction at a
first location on the wafer positioned in the bracket;

a second nozzle positioned to apply the second fluid in a second
direction at a second location on the wafer;

wherein the first and second locations are the regions on the wafer in
which the first and second fluids initially contact the wafer, respectively;

wherein the first and second directions are the initial directions of the
first and second fluid streams when initially contacting the wafer,
respectively;

wherein the second location is inboard of the first location and the
second location is downward of the first location in the first direction, but
the first fluid in the first direction does not intersect the second location; and

the first nozzle and the second nozzle are capable of pivoting across
the wafer about a common pivot point to translate the first location and the
second location from a wafer center to a wafer outer edge.

39. A single wafer cleaning apparatus, comprising:

a rotatable bracket capable of holding a wafer;

a first nozzle positioned to apply a first fluid at a first location, in a
first direction, on the wafer positioned in the bracket, the first location being
a first distance away from a center of the wafer; and

a second nozzle positioned to apply a second fluid at a second
location, in a second direction, on the wafer, the second location being a
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second distance away from the center of the wafer, the first distance being
greater than the second distance;

wherein the second fluid has a surface tension lower than the surface
tension of the first fluid;

wherein the combination of the first and second locations and the first
and second directions form a combination of first and second fluids streams
that generate a sustained surface tension gradient from the second fluid
stream to the first fluid stream on the surface of the wafer that increases in
an outward radial direction; and

wherein the positions of the first nozzle and the second nozzle are
such that the said surface tension gradient is maintained as the first and
second nozzles are pivoted across the wafer about a common pivot point.

As evidence of unpatentability of the appealed subject matter, the
Examiner proffered the following sole prior art reference:
Yoshitani US 5,975,098 Nov. 2, 1999

The Examiner rejected the claims on appeal as follows:
1) Claims 39, 40, and 42 under 35 U.S.C. § 102(a/e) as anticipated
by the disclosure of Yoshitani; and
2) Claims 1 through 5, 8, 9, and 41 under 35 U.S.C. § 103(a) as
unpatentable over the disclosure of Yoshitani.
Appellants appealed from the Examiner’s decision rejecting the
claims on appeal under 35 U.S.C. § 102(a/e) and 103(a).

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ISSUES
35 U.S.C. § 102(a/e)
Appellants contend that Yoshitani does not teach that its first and
second nozzles are positioned and/or configured to perform the claimed
functions (i.e., capable of ejecting first and second fluids having high and
low surface tensions, respectively, and applying the first and second fluids
on first and second distances with the first distance being further away from
the center of a wafer than the second distance to generate and maintain “a
sustained surface tension gradient from the second fluid stream to the first
fluid stream on the surface of the wafer that increases in an outward
direction” as required in claims 1 an 39) (Br. 9-29).
Thus, the first dispositive question raised in this case is whether there
is a reasonable basis to believe that Yoshitani’s appropriately positioned first
and second nozzles are capable of performing the claimed functions within
the meaning of 35 U.S.C. § 102(a/e)?
35 U.S.C. § 103
Appellants contend that Yoshitani does not teach or suggest the
claimed first and second fluids having high and low surface tensions as part
of its cleaning apparatus as required by claims 1, 2, 4, 5, 8, and 9 (29-40, 43,
and 44).
Thus, the second dispositive question is: Do the positively claimed
first and second fluids having high and low surface tensions, respectively, in
claims 1, 2, 4, 5, 8, and 9 limit the structures of their wafer cleaning
apparatus and if they limit the claimed structures, would one of ordinary
skill in the art have been led to employ the claimed first and second fluids in
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the wafer cleaning apparatus taught by Yoshitani within the meaning of 35
U.S.C. § 103(a)?
Appellants also contend that Yoshitani does not teach or suggest the
claimed distance between the claimed first and second nozzles as required
by claims 3 and 41 (Br. 40-47).
Thus, the third dispositive question is whether it is well within the
ambit of one of ordinary skill in the art to select the optimum distance
between Yoshitani’s first and second nozzles in the claimed manner for a
given wafer to be cleaned to optimize Yoshitani’s wafer cleaning within the
meaning of 35 U.S.C. § 103(a)?
CONCLUSIONS OF LAW
On this record, we find that there is a reasonable basis to believe that
Yoshitani’s appropriately positioned first and second nozzles are capable of
performing the claimed functions within the meaning of 35 U.S.C.
§ 102(a/e).
On this record, we determine that the positively claimed first and
second fluids having high and low surface tensions, respectively do not limit
the structures of the wafer cleaning apparatus recited in claims 1, 2, 4, 5, 8,
and 9, and even if they limit the claimed structures, one of ordinary skill in
the art would have been led to employ the claimed first and second fluids in
the wafer cleaning apparatus taught by Yoshitani within the meaning of 35
U.S.C. § 103(a).
On this record, we also determine that it is well within the ambit of
one of ordinary skill in the art to select the optimum distance between
Yoshitani’s first and second nozzles in the claimed manner for a given wafer
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to be cleaned to optimize Yoshitani’s wafer cleaning within the meaning of
35 U.S.C. § 103(a).
RELEVANT FACTUAL FINDINGS (FF)
The Factual Findings set forth below are supported by a
preponderance of the evidence:
1. Yoshitani teaches a wafer cleaning apparatus comprising a rotatable
chuck having arms 2 corresponding to the claimed rotatable bracket capable
of holding a wafer, rinsing nozzles (10, 20) rotatable in a direction of Ө2
from a common pivot point corresponding to the claimed first and second
nozzles having a common pivot point. (See Yoshitani, col. 1, ll. 5-22, col. 7,
l. 34 to col. 8, l. 45 and Fig. 1).
2. Yoshitani teaches that:
[T]he direction of the high-pressure rinsing nozzle 20 is
optionally adjustable by manual adjustment. Manual
adjustment is executed in a preparatory stage prior to actual
rinsing. During rinsing with the combined cleaning mechanism
50, the high-pressure rinsing nozzle 20 is fixed in an adjusted
direction. (See col. 8, ll. 40-45).

3. Yoshitani illustrates the locations and directions of nozzles 10 and 20,
with respect to the center of the rotatable wafer substrate in Figures 1 and 3
corresponding to Appellants’ Figure 1, useful for generating a Marangoni
force as shown below:
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4. Yoshitani does not mention its nozzles and rotatable bracket in terms
of the claimed functional limitations (i.e., nozzles capable of employing the
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claimed fluids and generating and maintaining the claimed sustained surface
tension gradient). (See generally Yoshitani.)
5. There is a reasonable basis to believe that Yoshitani’s wafer cleaning
apparatus is capable of employing the claimed fluids and generating and
maintaining the claimed surface tension gradient, since its rotatable bracket
and nozzles are positioned in the claimed manner for the claimed purpose,
i.e., cleaning a wafer. (Compare, e.g., Appellants’ Fig. 1 with Yoshitani’s
Figs. 1 and 3.)
6. Appellants have not proffered any evidence to show that Yoshitani’s
wafer cleaning apparatus does not have structural features capable of
performing the claimed functions. (See App. Br. and Reply Br. in their
entirety.)
7. Yoshitani teaches that its nozzles 10 and 20, which are capable of
being placed perpendicularly as shown in Figures 1 and 3, can be placed at
different angles and at a different appropriate distance from one another as
shown below in Figure 18:

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8. It is well within the common sense of one of ordinary skill in the art to
recognize that the distance between Yoshitani’s first and second nozzles is
dependent on the size of a wafer to be cleaned and/or of a wafer cleaning
apparatus.
9. Appellants acknowledge (Spec. 2, para. [0007]) that:
Marangoni drying is a commonly used method to dry wafers
after being processed in a wet bench. The method uses a
difference in surface tension gradients of IPA and DI water to
help remove water from the surface of the wafer. This surface
tension phenomenon is known as the Marangoni effect . . . .

PRINCIPLES OF LAW
“To anticipate a claim [under 35 U.S.C. § 102(a/e)], a prior art
reference must disclose every limitation of the claimed invention, either
explicitly or inherently.” In re Schreiber, 128 F.3d 1473, 1477 (Fed. Cir.
1997).
As stated in KSR Int’l Co. v. Teleflex, Inc., 127 S. Ct. 1727, 1734
(2007):
[35 U.S.C. § 103] forbids issuance of a patent when ‘the
differences between the subject matter sought to be patented
and the prior art are such that the subject matter as a whole
would have been obvious at the time the invention was made to
a person having ordinary skill in the art to which said subject
matter pertains.’

KSR disapproved a rigid approach to obviousness (i.e., an analysis
limited to lack of teaching, suggestion, or motivation). KSR, 127 S. Ct. at
1741 (“The obviousness analysis cannot be confined by a formalistic
conception of the words teaching, suggestion, and motivation, or by
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overemphasis on the importance of published articles and the explicit
content of issued patents.”); see also Alza Corp. v. Mylan Labs., Inc., 464
F.3d 1286, 1291 (Fed. Cir. 2006) (“There is flexibility in our obviousness
jurisprudence because a motivation may be found implicitly in the prior art.
We do not have a rigid test that requires an actual teaching to combine . . .
.”). As stated in our reviewing court in DyStar Textilfarben GmbH & Co.
Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356, 1367-68 (Fed. Cir.
2006), “[o]ur suggestion test is in actuality quite flexible and not only
permits, but requires, consideration of common knowledge and common
sense.” The common knowledge of one of ordinary skill in the art includes
those facts which are admittedly known in the art at the time of the
invention. In re Nomiya, 509 F.2d 566, 570-71 (CCPA 1975)(The admitted
prior art in an applicant’s Specification may be used in determining the
patentability of a claimed invention.); In re Davis, 305 F.2d 501, 503 (CCPA
1962).
KSR further instructs that
analysis [of whether the subject matter of a claim would
have been obvious] need not seek out precise teachings directed
to the 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, 127 S.
Ct. at 1740-41.

“[D]iscovery of an optimum value of a result effective variable . . . [, for
example,] is ordinarily within the skill of the art.” In re Boesch, 617 F.2d
272, 276 (CCPA 1980); see also In re Aller, 220 F.2d 454, 456 (CCPA
1955)(“[W]here the general conditions of a claim are disclosed in the prior
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art, it is not inventive to discover the optimum or workable ranges by routine
experimentation.”).
In making a patentability determination, any analyses must begin with
the question, “what is the invention claimed?” since “[c]laim interpretation, .
. . will normally control the remainder of the decisional process.” Panduit
Corp. v. Dennison Mfg. Co., 810 F.2d 1561, 1567-68 (Fed. Cir. 1987).
During examination, claims terms must be given their broadest reasonable
construction consistent with the specification. In re ICON Health and
Fitness, Inc., 496 F.3d 1374, 1379 (Fed. Cir. 2007)(“[T]he PTO must give
claims their broadest reasonable construction consistent with the
specification. . . . Therefore, we look to the specification to see if it provides
a definition for claim terms, but otherwise apply a broad interpretation.”).
However, the appropriate starting point for claim construction “is always
with the language of the asserted claim itself.” Comark Commc’ns, Inc. v.
Harris Corp., 156 F.3d 1182, 1186 (Fed. Cir. 1998).
“‘[T]here is nothing intrinsically wrong with [defining something by
what it does rather than what it is] in drafting patent claims.’” Schreiber,
128 F.3d at 1478 (quoting In re Swinehart, 439 F.2d 210, 212 (CCPA 1971))
. However, choosing to define the claimed apparatus functionally,
i.e., by what it does, has a risk. Schreiber, 128 F.3d at 1478 (quoting
Swinehart, 439 F.2d at 212). As our reviewing court stated in Schreiber, 128
F.3d at 1478 (quoting Swinehart, 439 F.2d at 213):
[W]here the Patent Office has reason to believe that a functional
limitation asserted to be critical for establishing novelty in the
claimed subject matter may, in fact, be an inherent
characteristic of the prior art, it possesses the authority to
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require the applicant to prove that the subject matter shown to
be in the prior art does not possess the characteristic relied on.

The Examiner has “reason to believe” that the claimed functional limitations
are present in a prior art apparatus if the structures of the claimed and prior
art apparatuses are either identical or substantially identical. See, e.g., In re
Best, 562 F.2d 1252, 1255 (CCPA 1977) (When “the claimed and prior art
products are identical or substantially identical . . . , the PTO can require an
applicant to prove that the prior art products do not necessarily or inherently
possess the characteristics of his claimed product . . . Whether the rejection
is based on ‘inherency’ under 35 U.S.C. § 102, on ‘prima facie obviousness’
under 35 U.S.C. § 103, jointly or alternatively, the burden of proof is the
same, and its fairness is evidenced by the PTO’s inability to manufacture
products or to obtain and compare prior art products.”); see also In re Spada,
911 F.2d 705, 708 (Fed. Cir. 1990) (“[W]hen the PTO shows sound basis for
believing that the products of the applicant and the prior art are the same, the
applicant has the burden of showing that they are not.”).
ANALYSES
I. CLAIMS 39, 40, AND 42 UNDER 35 U.S.C. § 102
As indicated supra, Yoshitani teaches a wafer cleaning apparatus
comprising a rotatable chuck having arms 2 corresponding to the claimed
rotatable bracket capable of holding a wafer, nozzles (20 and 10) for rinsing
liquid rotatable in a direction of Ө2 from a common pivot point
corresponding to the claimed first and second nozzles having a common
pivot point. Yoshitani also teaches that nozzle 20 can be manually adjusted
to an appropriate position and exemplifies the adjusted locations of nozzles
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20 and 10 in Figure 3 corresponding to Appellants’ Figure 1, to apply their
rinsing liquids at the claimed first and second distances.
Although Yoshitani does not mention its nozzles and rotatable bracket
in terms of the claimed functional limitations (i.e., nozzles capable of
employing the claimed fluids and generating and maintaining the claimed
sustained surface tension gradient), it is reasonable for the Examiner to
believe that Yoshitani’s wafer cleaning apparatus is capable of performing
such functions since its rotatable bracket and nozzles are positioned in the
claimed manner for the claimed purpose, i.e., cleaning a wafer. In other
words, the Examiner had a reasonable basis for believing that the structures
of the claimed and Yoshitani’s wafer cleaning apparatuses are either
identical or substantially identical. Yet, Appellants have not proffered any
evidence to show that the wafer cleaning apparatus taught by Yoshitani does
not possess structural features capable of performing the claimed functions.
Accordingly, we concur with the Examiner that Yoshitani renders the
subject matter recited in claims 39, 40, and 42 anticipated within the
meaning of 35 U.S.C. § 102(a/e).
II. CLAIMS 1-5, 8, 9, AND 41 UNDER 35 U.S.C. § 103(a)
A. CLAIMS 1, 2, 4, 5, 8, AND 9
As indicated supra, Yoshitani teaches a wafer cleaning apparatus
comprising a rotatable chuck having arms 2 corresponding to the claimed
rotatable bracket capable of holding a wafer, nozzles (20 and 10) for rinsing
liquid rotatable in a direction of Ө2 from a common pivot point
corresponding to the claimed first and second nozzles having a common
pivot point. Yoshitani also teaches that nozzle 20 can be manually adjusted
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to an appropriate position and exemplifies the adjusted locations of nozzles
20 and 10 in Figure 3 corresponding to Appellants’ Figure 1, to apply their
rinsing liquids at the claimed first and second locations. Yoshitani further
teaches that its nozzles 10 and 20 can be placed perpendicularly and/or at
different angels as shown in Figures 1, 3, and 18.
Although claims 1, 2, 4, 5, 8, and 9 are different from Yoshitani in
positively reciting first and second fluids having different surface tensions as
part of the claimed apparatus, the Specification and the claims clearly
indicate that they are the fluids to be worked upon by, not the structural
features of, the claimed wafer cleaning apparatus. The preamble
terminology “apparatus” connotes that the claimed wafer cleaning apparatus
is limited to its structural features, not the fluids to be sprayed. As such, we
find no distinction between the claimed and Yoshintani’s wafer cleaning
apparatuses since there is no reasonable basis to believe that the nozzles
taught by Yoshitani are incapable of employing such fluids as indicated
supra.
Even assuming that the positively claimed fluids must be treated as
part of the claimed wafer cleaning apparatus, the outcome of this case
remains the same. Specifically, Appellants acknowledge that:
Marangoni drying is a commonly used method to dry wafers
after being processed in a wet bench. The method uses a
difference in surface tension gradients of IPA and DI water to
help remove water from the surface of the wafer. This surface
tension phenomenon is known as the Marangoni effect. . . .

Thus, one of ordinary skill in the art would have been led to employ the
claimed fluids, namely IPA and DI water, with additional nozzles or the
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existing nozzles taught by Yoshitani to eject them at optimum locations,
after completing the wet cleaning (wet batch) taught by Yoshintani, with a
reasonable expectation of successfully drying the cleaned wafer (wet batch).
Accordingly, based on the totality of record, including due
consideration of Appellants’ arguments, we determine that the
preponderance of evidence weighs most heavily in favor of obviousness
regarding the subject matter recited in claims 1, 2, 4, 5, 8, and 9 within the
meaning of 35 U.S.C. § 103(a).
B. CLAIMS 3 AND 41
The relevant disclosure of Yoshitani is discussed above. Yoshitani
does not specifically mention the distances between the first and second
nozzles as required by claims 3 and 41. However, Yoshitani illustrates that
its nozzles can be placed in various distances from one another. More
importantly, it is well within the common sense of one of ordinary skill in
the art to recognize that the distance between Yoshitani’s first and second
nozzles is dependent on the size of a wafer to be cleaned and/or of a wafer
cleaning apparatus. In other words, the distance between Yoshitani’s first
and second nozzles is a recognized result effective variable. Thus, we concur
with the Examiner that it is well within the ambit of one of ordinary skill in
the art to select the optimum distance between Yoshitani’s first and second
nozzles and/or suggested additional nozzles, such as that claimed, for the
purpose of cleaning, for example, a given sized wafer.
Accordingly, based on the totality of record, including due
consideration of Appellants’ arguments, we determine that the
preponderance of evidence weighs most heavily in favor of obviousness
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regarding the subject matter recited in claims 3 and 41 within the meaning of
35 U.S.C. § 103(a).

ORDER
The decision of the Examiner is affirmed.

TIME PERIOD
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

ssl

MICHAEL A. BERNADICOU
BLAKELY, SOKOLOFF, TAYLOR & ZAFMAN L.L.P
1279 OAKMEAD PARKWAY
SUNNYVALE, CA 94085-4040

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