Ex Parte Aggarwal et al

Board of Patent Appeals and Interferences

Mar 11, 2008

10434534 (B.P.A.I. Mar. 11, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte RAVINDER AGGARWAL and JAMES F. KUSBEL
____________

Appeal 2007-2688
Application 10/434,534
Technology Center 3600
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Decided: March 12, 2008
____________

Before DONALD E. ADAMS, ERIC GRIMES, and RICHARD M.
LEBOVITZ, Administrative Patent Judges.

LEBOVITZ, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal from the final rejection of claims 1, 2, 6,
7, 24, 25, 31, and 32. We have jurisdiction under 35 U.S.C. § 6(b). We
affirm.

Appeal 2007-2688
Application 10/434,534

STATEMENT OF THE CASE
The claims are directed to substrate processing systems. According to
the Specification, a semiconductor device is fabricated on a thin slice of
semiconductor material “termed a substrate or wafer” (Spec. 1: 11-13). The
Specification states that when “manufacturing these devices, it is imperative
that the substrate does not become contaminated by particulate.
Accordingly, substrate processing systems typically include a load lock
apparatus that provides a substantially particle free environment from which
substrates may be selectively withdrawn by a substrate handling assembly
for placement into one or more processing modules” (Spec. 1: 13-18).
However, the Specification states that the load lock “tends to increase the
footprint of the substrate processing station” (Spec. 1: 20-21). As a solution,
the Specification describes placing a staging shelf above the load lock to
allow the substrate to cool without reducing throughput or increasing the
footprint size (Spec. 1: 29 to 2: 8).
Claims 1, 2, 6, 7, 24, 25, 31, and 32, which are all the pending claims,
are appealed (App. Br. 4). Appellants request our review of the following
rejections:
1) Claims 1 and 2 under 35 U.S.C. § 103(a) as obvious over Iwai
(U.S. Pat. No. 5,829,939, Nov. 3, 1998) and Tabrizi (U.S. Pat. No.
6,647,665 B1, Nov. 18, 2003) (Ans. 4);
2) Claims 6 and 7 under 35 U.S.C. § 103(a) as obvious over Iwai,
Tabrizi, and Flegal (U.S. Pat. No. 5,516,732, May 14, 1996) (Ans. 5);
3) Claims 24 and 25 under 35 U.S.C. § 103(a) as obvious over Iwai
and Flegal (Ans. 5); and
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4) Claims 31 and 32 under 35 U.S.C. § 103(a) as obvious over Iwai,
Flegal, and Suda (U.S. Pat. No. 6,053,980, Apr. 25, 2000) (Ans. 6).
Claims 1, 6, 7, 24, 31, and 32, which are representative of the
appealed subject matter, read as follows:
1. A substrate processing system comprising:
a substrate handling chamber;
a load lock chamber having a gated inlet for the transfer
of a substrate into and out of the load lock chamber, and having
a gated port for transferring a substrate between the load lock
chamber and the substrate handling chamber;
a staging shelf in the handling chamber positioned
directly above the load lock chamber; and
a first substrate handler in the substrate handling chamber
for moving a substrate between the load lock chamber and the
staging shelf.

6. The substrate processing system Claim 1, including a cooling
station within the substrate handler chamber accessible by the
substrate handler.

7. The substrate processing system of Claim 6, further
comprising a rest station within the handling chamber that is
accessible by the first substrate handler and a gated port
adjacent the rest station for the transfer of substrates to an
adjacent process chamber.

24. A substrate processing system comprising a substrate
handling chamber, a load lock port in a wall of the substrate
handling chamber for the transfer of a substrate from a load
lock chamber to the substrate handling chamber, a staging shelf,
a rest station, a cooling station all within the substrate handling
chamber, and a first substrate handler configured to move the
substrate to and from the load lock chamber, the staging shelf,
the rest station and the cooling station.

31. The substrate processing system of Claim 1, wherein the
first substrate handler is configured to handle a single substrate.
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32. The substrate processing system of Claim 24, wherein the
first substrate handler is configured to handle a single substrate.

DISCUSSION
Claims 1 and 2
Claims 1 and 2 stand rejected under 35 U.S.C. § 103(a) as obvious
over Iwai in view of Tabrizi.
Claim 1 is directed to a substrate processing system comprising: 1) a
substrate handling chamber; 2) a load lock; 3) “a staging shelf in the
handling chamber positioned directly above the load lock chamber”; and 4) a
first substrate handler.
The Examiner finds that Iwai describes all the elements of claim 1,
including a substrate handling chamber (321), a load lock chamber (210), a
staging shelf (320), and a first substrate handler (322), but does not describe
the staging shelf “in the handling chamber positioned directly above the load
lock chamber” as recited in claim 1 (Ans. 4; see Iwai, Fig. 24). However,
the Examiner finds that Tabrizi describes a substrate processing system
which comprises two load locks (406a and 406b) situated directly on top of
each other (Ans. 4; Tabrizi, Fig. 4). The second load lock contains staging
shelves 416 (Tabrizi, Fig. 4), which the Examiner finds are located “directly
above” the first load lock chamber as in claim 1 (Ans. 4). The Examiner
contends that it would have been obvious to persons of ordinary skill in the
art “to use the area above the load lock taught by Iwai et al. by providing
staging shelves as taught by Tabrizi et al. in order to increase the throughput
of the device without increasing the footprint of the device” (id.).
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Appellants argue that there is an opening device 234 and gas pipes
224 and 225 in the space directly above the load lock and thus “the
modification suggested by the Examiner would radically alter the
configuration taught by the Iwai patent” (App. Br. 10; see Reply Br. 1-2; see
Iwai, at Fig. 24).
We are not persuaded by Appellants’ argument that the Examiner
erred in the obviousness determination. As the Examiner points out, the
“space directly above the load lock (of which element 234 [and 224 and 225
are] . . . part) is open and . . . large enough to have . . . staging shelves
mounted thereon. See figure 24 of the Iwai patent” (Ans. 8). We also agree
with the Examiner that the phrase “directly above” as recited in claim 1 is
reasonably interpreted to mean “overhead of the load lock” and that there is
no language in the claim which would exclude there from being “an
intervening structure between the load lock and the shelves” (id.). Thus,
staging shelves could be fit into the space above Iwai’s load lack chamber
210, without “radically” altering the handling chamber’s configuration as
asserted by Appellants.
Appellants also contend that the “Tabrizi patent merely teaches
placing a pair of load lock chambers 406a, 406b positioned on top of each
other” which does not satisfy the limitation of claim 1 that the shelves are in
the handling chamber (App. Br. 10).
This argument is not persuasive. The Examiner relies on Tabrizi for
its general teaching that vertical stacking of components in a substrate
processing system saves space (Ans. 7; see Tabrizi, at col. 2, ll. 39-41; at
col. 4, ll. 9-12). Thus, whether the claim is interpreted to exclude the staging
shelves from being part of a second load lock “directly above” the first load
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lock is not dispositive since Tabrizi would have reasonably suggested
placing a component, such as a staging shelf, above Iwai’s load lock to
increase staging space to achieve high throughput. For instance, Tabrizi
states
the load locks may provide the capability to cool post process
workpieces prior to or during their pressure transition from the
reduced pressure of the load lock to atmospheric pressure. This
functional independence makes such a system capable of
providing a steady supply of pre-processed workpieces for the
vacuum handler thus achieving high throughput in nearly
continuous workpiece processing.
(Tabrizi, at col. 3, ll. 32-39) Thus, the load lock, when used to cool post
process wafers, serves the same function as a staging shelf.
Appellants argue that “moving the shelves within the staging shelf
320 would not decrease the foot print of the system and thus one of skill in
the art would not be motivated to make the suggested design change”
because “shelves are positioned at the same elevation as the loading area 208
and are located between the load lock and the loading area 208”
(Reply Br. 2).
We are not convinced by this argument that the Examiner erred.
Given the wide variety of configurations which are described in the prior art
for substrate handling systems (see generally Iwai and Tabrizi, e.g., Figs. 24
and 4, respectively), we find that the persons of ordinary skill in the art were
familiar with their design and that it would have been within the scope of
ordinary skill to mount staging shelves at any location in a transfer chamber
in order to save space and increase throughput (see Ans. 7). When “a patent
‘simply arranges old elements with each performing the same function it had
been known to perform’ and yields no more than one would expect from
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such an arrangement, the combination is obvious.” KSR Int’l Co. v. Teleflex
Inc., 127 S. Ct. 1727, 1740 (2007).
For the foregoing reasons, we affirm the rejection of claim 1. Claim 2
falls with claim 1 because separate reasons for its patentability were not
provided. See 37 C.F.R. § 41.37(c)(1)(vii).

Claims 6 and 7
Claims 6 and 7 stand rejected under 35 U.S.C. § 103(a) as obvious
over Iwai, Tabrizi, and Flegal.
Claims 6 and 7 further comprise a cooling and rest station,
respectively. The Examiner finds that these elements are described in Flegal
and that it would have been obvious to persons of ordinary skill in the art to
have incorporated these elements into Iwai’s apparatus to increase the
system’s throughput (Ans. 5).
Appellants do not challenge the Examiner’s determination (see App.
12), and as we find no defect in it, we affirm the rejection of claim 6 and 7.

Claims 24 and 25
Claims 24 and 25 stand rejected under 35 U.S.C. § 103(a) as obvious
over Iwai and Flegal.
Claim 24 is directed to a substrate processing system which
comprises: 1) a substrate handling chamber; 2) a load lock port; 3) a staging
shelf; 4) a rest station; 5) a cooling station; and 6) a substrate handler.
The Examiner finds that Iwai teaches a substrate handling chamber, a
load lock, a staging shelf or rest station, and a substrate handler, but does not
describe a cooling station as recited in claim 24 (Ans. 5-6). However, the
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Examiner finds that Flegal teaches a cooling station in a substrate (“wafer”)
handling system. Thus, the Examiner concludes that it would have been
obvious to persons of ordinary skill in the art to have incorporated the
cooling station into Iwai’s system
in order to have a place to cool substrates outside of the process
chamber so as to cool a processed substrate prior to placing it
an [sic, on] a transfer cassette while at the same time freeing the
process chamber for a second wafer to be processed, thereby
increasing the throughput of the system.
(Ans. 6).
Appellants state that Iwai “is directed to a batch type reactor in which
many wafers are processed in the reactor at one time” (App. Br. 12-13).
Thus, Appellants contend that the “function” of a cooling station “is not
required because of the large number of substrates that are moved into and
out of the reactor at the same time” (App. Br. 13).
We agree with the Examiner that the “time saving” conferred by a
cooling station “would apply no mat[t]er how many wafers are processed
together” (Ans. 9). “It is well known in the art that increasing the
throughput is important to a wafer manufacturer, therefore one of ordinary
skill in the art would have contemplated using a cooling device in the Iwai
reference to speed up cycle times, thereby increasing the yield of” wafers
(id.). As Appellants have provided no evidence or arguments to the
contrary, we affirm the rejection of claim 24. Claim 25 falls with claim 24
because separate reasons for its patentability were not provided. See 37
C.F.R. § 41.37(c)(1)(vii).

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Appeal 2007-2688
Application 10/434,534

Claims 31 and 32
Claims 31 and 32 stand rejected under 35 U.S.C. § 103(a) as obvious
over Iwai, Flegal, and Suda.
Claims 31 and 32 are directed to the substrate processing system of
claims 1 and 24, respectively, but where “the first substrate handler is
configured to handle a single substrate.” The Examiner finds that Suda
teaches “a substrate processing system substantially similar to that of Iwai et
al. where a first substrate handler (20) can move both cassettes of wafers and
single wafers based on predetermined needs of the system” (Ans. 6). The
Examiner concludes that it would have been obvious to persons of ordinary
skill in that art “to provide the device taught by Iwai et al. with the substrate
handler as taught by Suda et al. in order to allow the handler to move either a
plurality of substrates or a single substrate depending on the needs of the
device” (Ans. 7).
Appellants contend that “Suda did not provide any disclosure,
teaching or motivation for placing a cooling station within the substrate
handling chamber as claimed in independent Claim 24 or for positioning a
staging shelf in the handling chamber positioned directly above the load lock
chamber as in independent Claim 1” (App. Br. 13).
The Examiner argues that such limitations are found in prior art
references already cited and that Suda is relied upon for teaching a handler
that moves a single wafer, and not for the limitations argued by Appellants
(Ans. 9). As we agree with the Examiner that limitations argued by
Appellants can be found in the prior art of record, we affirm the rejection of
claims 31 and 32.
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Appeal 2007-2688
Application 10/434,534

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

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