Ex Parte Koshiishi et al

Patent Trial and Appeal Board

Aug 9, 2016

13113330 (P.T.A.B. Aug. 9, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/113,330 05/23/2011 Akira Koshiishi
22850 7590 08/11/2016
OBLON, MCCLELLAND, MAIER & NEUSTADT, LLP,
1940 DUKE STREET
ALEXANDRIA, VA 22314
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
380493US41CONT 9431
EXAMINER
CHEN, KEATH T
ART UNIT PAPER NUMBER
1716
NOTIFICATION DATE DELIVERY MODE
08/11/2016 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address( es):
patentdocket@oblon.com
oblonpat@oblon.com
ahudgens@oblon.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte AKIRA KOSHIISHI, MASARU SUGIMOTO,
KUNIHIKO HINATA, NORIYUKI KOBAYASHI,
CHISHIO KOSHIMIZU, RYUJI OHTANI, KAZUO KIBI,
MASASHI SAITO, NAOKI MATSUMOTO, MANABU IWATA,
DAISUKE Y ANO, YOHEI Y AMAZA WA, HIDETOSHI HANAOKA,
TOSHIHIRO HAY AMI, HIROKI YAMAZAKI, and MANABU SAT0 1
Appeal2015-002539
Application 13/113,330
Technology Center 1700
Before WESLEY B. DERRICK, CHRISTOPHER C. KENNEDY, and
JENNIFER R. GUPTA, Administrative Patent Judges.
KENNEDY, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134(a) from the Examiner's
decision to reject claims 21-24. We have jurisdiction under 35 U.S.C.
§ 6(b ).
We AFFIRM.
1 According to the Appellants, the real party in interest is Tokyo Electron
Limited. App. Br. 1.
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Application 13/113,330
BACKGROUND
The subject matter on appeal relates to a plasma processing apparatus.
See, e.g., Spec. 1:18-20; Claim 21. Claim 21 is reproduced below from
page 36 (Claims Appendix) of the Appeal Brief (some formatting added):
21. A plasma processing apparatus exclusively used for etching a
target substrate, the apparatus comprising:
a process container configured to accommodate the target
substrate and to be vacuum-exhausted;
a first electrode and a second electrode disposed opposite each
other within the process container, the first electrode being an
upper electrode and the second electrode being a lower electrode
and configured to place the target substrate thereon;
a first RF power application unit connected to the second
electrode and configured to apply a first RF power for plasma
generation, the first RF power having a frequency of 27 MHz or
more;
a second RF power application unit connected to the second
electrode and configured to apply a second RF power for ion
attraction, the second RF power having a frequency of 13.56
MHz or less lower than that of the first RF power;
a DC power supply connected to the first electrode and
configured to apply a DC voltage of -2,000 to + 1,000V, the first
electrode being connected to no power supply for applying an
RF power;
a process gas supply unit configured to supply a process gas into
the process container;
a showerhead built in the first electrode and configured to
distribute the process gas in the process container, the
showerhead including a plurality of gas delivery holes formed in
the first electrode and opened at a bottom face of the first
electrode and a gas diffusion cell present above the gas delivery
holes and interconnecting the process gas supply unit with the
gas delivery holes;
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a first switch disposed between the first electrode and the DC
power supply and configured to be turned on and off to switch
connection between the first electrode and the DC power supply
in a sense of DC;
a second switch disposed between the first electrode and ground
potential and configured to be turned on and off to switch the
first electrode between a grounded state where the first electrode
is connected to the ground potential in a sense of DC and a
floating state where the first electrode is not connected to the
ground potential in a sense of DC; and
a control section configured to control an operation of the plasma
processing apparatus and including, as parts of the control
section, a computer and a non-transitory storage medium storing
a control program for execution on the computer,
wherein the control program, when executed, causes the
computer to control the plasma processing apparatus to
selectively set first and second plasma etching modes each for
etching the target substrate while applying both of the first and
second RF powers to the second electrode,
the first plasma etching mode being a mode where the first
switch is set on to apply a DC voltage to the first electrode
while the second switch is set off to keep the first electrode
only in the floating state, and
the second plasma etching mode including a submode where
the first switch is set off not to apply any DC voltage to the
first electrode while the second switch is set on to set the first
electrode in the grounded state.
REJECTIONS ON APPEAL
1. Claims 21and24 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Zhao et al. (US 5,968,379, issued Oct. 19, 1999) in view
of Arai et al. (US 6, 110,287, issued Aug. 29, 2000), Koshiishi et al.
(EP 1 193 746 Al, published Apr. 3, 2002), and Kholodenko et al.
(US 2003/0129835 Al, published July 10, 2003).
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2. Claim 22 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Zhao in view of Arai, Koshiishi, and Kholodenko, further in view of
Ohmi et al. (US 5, 110,438, issued May 5, 1992), Fujioka et al.
(US 6,287,943 Bl, issued Sept. 11, 2001), and Kuyel (US 4,333,814, issued
June 8, 1982).
3. Claim 23 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Zhao in view of Arai, Koshiishi, and Kholodenko, further in view of
Kent et al. (US 2001/0035132 Al, published Nov. 1, 2001).
ANALYSIS
The Appellants' arguments focus on limitations that appear in claim
21. See generally App. Br. 12-34. Therefore, our decision on the
Examiner's rejection of claim 21 is dispositive of all claims on appeal.
After review of the cited evidence in the appeal record and the
opposing positions of the Appellants and the Examiner, we determine that
the Appellants have not identified reversible error in the Examiner's
rejections. Accordingly, we affirm the rejections for reasons set forth below,
in the Non-Final Action dated April 7, 2014, and in the Examiner's Answer.
See generally Non-Final Act. 3-14; Ans. 2-12.
As an initial matter, we note that claim 21 may inadvertently include
language that results in some ambiguity as to claim scope. In particular, it
recites "a second RF power application unit ... having a frequency of 13.56
MHz or less lower than that of the first RF power." (emphasis added). The
language "lower than that of the first RF power" may have been
inadvertently carried over from earlier-pending, now-canceled claims, and it
appears that the Appellants may have intended simply to recite that the
second RF power has "a frequency of 13.56 MHz or less[.]" See, e.g., Spec.
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4: 16-17 ("It is preferable that the second RF power applied to the second
electrode has a frequency of 13.56 MHz or less."), 17:2-3 (similar), 40:8-10
(similar). In the event of further examination of the application on appeal,
we leave it to the Examiner and the Appellants to address that issue. See 37
C.F .R. § 41. 50(b) (issuance of a new ground of rejection is at the discretion
of the Board).
Notwithstanding the above concern, we reach the rejections on appeal
as the briefing indicates that both the Examiner and the Appellants treated
the limitation as reciting "13.56 MHz or less." See, e.g., Ans. 2; App. Br. 17
(referencing "the claimed second RF power application unit having the
claimed frequency of 13.56 MHz or less").
The Examiner finds that Zhao teaches a plasma processing apparatus
comprising each element of claim 21 except that (1) Zhao teaches only a
single RF power application unit connected to the lower electrode, (2) Zhao
does not teach the specific DC voltage range of -2000 to + 1 OOOV, (3) Zhao
does not teach the claimed first and second switches, and ( 4) Zhao does not
teach a control section/control program. Ans. 2-3.
Concerning the use of first and second RF power application units
connected to the lower electrode, the Examiner finds that Arai teaches an
apparatus comprising those features, and the Examiner concludes that it
would have been obvious "to have added a dual frequency RF supply to
[Zhao], one at high frequency ... and the other at low frequency ... for the
purpose of high plasma dissociation efficiency at high-frequency while
preventing the charge-up due to continued use of such high frequency." Id.
at 4.
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Concerning the specific DC voltage range of claim 21, the Examiner
finds that Koshiishi teaches a DC power supply that operates at -400 V
connected to an upper electrode, and the Examiner concludes that it would
have been obvious to operate Zhao's voltage source at that voltage "for the
purpose of suppressing the unevenness in plasma density." Id.
Concerning the first and second switches, the Examiner finds that,
while Zhao teaches an upper electrode that is either grounded or DC biased,
Zhao "does not explicitly teach a switch to alternate between ground and DC
bias." Id. at 5. The Examiner finds that Kholodenko teaches a three-pole
switch attached to a ceiling electrode that switches between RF power,
ground, and a floating state in order to achieve desired cleaning properties.
Id. The Examiner suggests that, because Kholodenko's three-pole switch
includes all of the features of claim 21 's first and second switches,
Kholodenko' s three-pole switch is equivalent to claim 21 's first and second
switches. Id. at 11. The Examiner concludes that it would have been
obvious to add such a switch to Zhao (using Zhao's DC bias rather than
Kholodenko's RF power), including a floating state, "for the purpose of
cleaning procedure as taught by [Kholodenko] and/or for its suitability with
predictable results." Id. at 5.
Concerning the control section and program, the Examiner finds that
Arai teaches a "controller/computer" and concludes that "it would have been
obvious ... to perform the switching of various states." Id. The Examiner
further finds that "any person of ordinary skill in the art would have applied
program control to the processing requirement as taught by [Kholodenko,
Zhao, and Koshiishi] to automate the process." Id. at 10.
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In view of those findings, the Examiner concludes that the apparatus
of claim 21 would have been obvious over the combined prior art. Ans. 2-5.
The Appellants present several arguments in opposition to the
Examiner's rejection, which we address in tum below.
1. The Appellants argue that the preamble of claim 21, "[a] plasma
processing apparatus exclusively used for etching a target substrate"
(emphasis added), is limiting, see App. Br. 12-14, contrary to the
Examiner's conclusion that it is not, see Non-Final Act. 3. The Appellants'
focus appears to be on the word "exclusively," as there is no apparent
dispute as to whether the prior art apparatuses are capable of etching. See
App. Br. 12-14; Ans. 8.
We are not persuaded by the Appellants' argument. "If ... the body
of the claim fully and intrinsically sets forth the complete invention ... and
the preamble offers no distinct definition of any of the claimed invention's
limitations, but rather merely states, for example, the purpose or intended
use of the invention, then the preamble is of no significance to claim
construction because it cannot be said to constitute or explain a claim
limitation." Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298,
1305 (Fed. Cir. 1999). "[A]pparatus claims cover what a device is, not what
a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d
1464, 1469 (Fed. Cir. 1990) (emphasis in original).
Here, the preamble's recitation that the apparatus is "exclusively used
for etching a target substrate" is the type of "purpose or intended use" that
typically fails "to constitute or explain a claim limitation." See Pitney
Bowes, 182 F.3d at 1305. The Appellants have not argued persuasively to
the contrary or shown a difference in structure resulting from the preamble.
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While etching is again referred to in the body of the claim, that suggests no
more than that the apparatus must be capable of etching. The Appellants do
not argue that the prior art apparatuses are not capable of etching. See
generally App. Br.; Reply Br.
Moreover, even if the word "exclusively" in the preamble were
limiting, the Appellants have not persuasively argued that exclusive use for
etching would not have been obvious in view of an apparatus, for example,
that is capable of both etching and deposition. See, e.g., Ans. 8. Thus, their
argument fails to show reversible error in the rejection, even if the preamble
were to limit the claimed apparatus to etching. 2
2. The Appellants argue that the Examiner improperly "divided [the
elements of the claimed invention] into a plurality of small elements, and
searched for [the elements] individually in order to find similar elements in
the art." App. Br. 15-22. The Appellants further argue that the Examiner's
findings concerning the claimed "control section" are "conclusory" and lack
"rational underpinning to support the legal conclusion of obviousness." Id.
at 21.
While we agree that the Examiner relied on different prior art
references for various different elements of claim 21, the Appellants fail to
persuasively identify reversible error in the Examiner's rationale. To the
2 We note that the originally filed claims did not purport to limit the
apparatus to "exclusive[] use[]" for etching. See, e.g., Claims dated May 23,
2011. The exclusive use language appears to have been added in an August
8, 2013, claim amendment. In the Appeal Brief, the Appellants do not
identify any written description support in the Specification for the exclusive
use language that they now argue is limiting. See App. Br. 3 (listing
Specification support for the preamble of claim 21 ).
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extent the Appellants provide a summary of the references and an
identification of which elements of claim 21 each individual reference fails
to teach, see App. Br. 15-22, that is not persuasive of reversible error. See
In re Keller, 642 F.2d413, 426(CCPA1981) ("[O]ne cannot shownon-
obviousness by attacking references individually where, as here, the
rejections are based on combinations of references."); see also In re
McLaughlin, 443 F.2d 1392, 1395 (CCPA 1971) ("Any judgment on
obviousness is in a sense necessarily a reconstruction based upon hindsight
reasoning, but so long as it takes into account only knowledge which was
within the level of ordinary skill at the time the claimed invention was made
and does not include knowledge gleaned only from applicant's disclosure,
such a reconstruction is proper.").
As the Examiner explains, Zhao teaches an apparatus with an upper
electrode ( showerhead) that is DC biased or grounded, and a lower electrode
that is connected to RF power. Ans. 2-3; Zhao at 28:50-29:7, 29:44--47,
31 :25-28. Arai teaches an apparatus with first and second RF power
supplies (high frequency and low frequency) connected to the lower
electrode and a controller for controlling the power supplies. See, e.g., Arai
at Fig. 1, 5:36-38. Arai, like the Appellants' Specification, teaches that the
high frequency RF power supply generates plasma, while the low frequency
RF power supply, inter alia, affects "movement of ions." Compare Arai at
6:30-33, 6:53-56 with Spec. 14:9-11 ("[A] radio frequency (RF) power
with, e.g., 40 MHz for plasma generation from a first RF power supply ...
and a radio frequency (RF) with, e.g., 2 MHz for ion attraction .... ").
Koshiishi likewise teaches an apparatus with both a high frequency
and a low frequency RF power supply, serving the same purposes as the
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high frequency and low frequency RF power supplies of Arai and the
Appellants' Specification (i.e., plasma generation and ion attraction), but
Koshiishi' s RF power supplies are connected to different electrodes rather
than to the same electrode. See, e.g., Koshiishi Fig. 16, i-f 42, i-f 44.
Koshiishi also teaches a DC power supply connected to the upper electrode
to improve uniformity of plasma density, similar to a purpose of the DC
power supply taught by the Appellants. Compare id. i-f 124 with Spec.
25:21-23. The Appellants do not identify any teaching in Koshiishi
suggesting that its DC power supply functions only if an RF power supply is
also attached to the upper electrode. Thus, as the Examiner finds, ( 1) the use
of high and low frequency RF power supplies, either both connected to the
lower electrode or one connected to each electrode, in order to generate
plasma and affect ion movement, and (2) the use of DC bias at the upper
electrode to improve plasma density, were known in the art. The Appellants
fail, accordingly, to persuade us that the Examiner's proposed modifications
to Zhao are any more than the use of known elements according to their
known functions with predictable results. See KSR Int'! Co. v. Teleflex Inc.,
550 U.S. 398, 416 (2007) ("The combination of familiar elements according
to known methods is likely to be obvious when it does no more than yield
predictable results.").
Concerning the use of first and second switches, the Examiner finds
that Kholodenko teaches the use of a three-pole switch that permits
connection of the upper electrode to ground, to a floating potential, or to an
RF power supply. Ans. 5; Kholodenko Fig. 5, i-f 22, i-f 39. As the Examiner
explains, and the Appellants do not persuasively dispute, Kholodenko's
switch is equivalent to, or otherwise renders obvious, the first and second
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switches of claim 21 because it functions in the same way; i.e., permits three
selections: power (without grounding), ground, or float. See Ans. 11; see
also Spec. 29:7-24 (disclosing that DC voltage has an effect only when the
upper electrode is not grounded, and that when DC voltage is off, the upper
electrode can be grounded or floating). Kholodenko suggests that the "etch
rate" in certain parts of the chamber can be "enhance[ d]" by choosing
grounded or floating state. Kholodenko i-f 22. In view of those teachings,
the Examiner concludes that it would have been obvious to add a three-pole
switch and a floating state to the upper electrode of Zhao, which Zhao
teaches may be DC biased or grounded, and to select between DC bias,
ground, and floating state, to improve etching or cleaning functionality.
Ans. 5, 11.
Concerning the control section and program, the use of control
systems to control various features of apparatuses similar to that of claim 21
was known in the art. Zhao discloses "a control system, including a
processor and a memory." Zhao at 5:31-34. Arai discloses a controller that
controls a high frequency power supply, a low frequency power supply, and
a modulating device. Arai at 5:36-38. As the Examiner explains, it would
be obvious to use such a control system to automate any particular process
or element of the apparatuses of the prior art, including the switches. Ans.
10. Although the Appellants fault the Examiner for allegedly failing to find
that one of the switch states (DC bias off, second switch set to ground)
would have been obvious, see App. Br. 25-26, the Examiner's proposed
modification includes only 3 switch states: DC bias (without grounding),
ground, or float. The Examiner suggests that, when the three-pole switch is
in the "ground" state, the state of the apparatus and switching would be
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equivalent to claim 21 's DC bias being off with second switch set to ground.
See Ans. 11. The Appellants' arguments do not persuade us of reversible
error in that finding, or that the Examiner erred reversibly in concluding it
would have been obvious to use a control system to automate control of the
switch, including to any of its three states.
In view of the evidence, and contrary to the Appellants' arguments,
we are not persuaded that the Examiner's rationale lacks the requisite
"articulated reasoning with some rational underpinning to support the legal
conclusion of obviousness." See App. Br. 21 (emphasis omitted); In re
Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006).
3. The Appellants argue that the Examiner did not give weight to the
"hardware-software combination" of claim 21. See App. Br. 22-24. Other
than claim elements discussed above, the Appellants fail to identify any
particular claim element to which the Examiner allegedly failed to give
weight.
As explained above, the Examiner determines that it would have been
obvious to use a control system to automate the processes of the apparatuses
of the prior art. While the Appellants argue that a person of ordinary skill in
the art "would not know to program any of the prior art processors in the
manner set forth by the control program of Claim 21," see App. Br. 26, that
argument is not supported by persuasive evidence or technical reasoning.
See In re Pearson, 494 F.2d 1399, 1405 (CCPA 1974) ("Attorney's
argument in a brief cannot take the place of evidence."). Further, the record
reflects that it was known that applying a DC bias to an upper electrode
affects plasma density, and that the ground/float state of the upper electrode
can be adjusted to enhance etching/cleaning. We are not persuaded that it
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would have been beyond the level of ordinary skill in the art to program the
three-pole switch of Zhao as modified by Arai, Koshiishi, and Kholodenko
to achieve any of its three potential states. See KSR, 550 U.S. at 418-19
("[T]he [obviousness] analysis 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.").
4. Relying on various references that apparently were part of a
previous Office Action, but upon which the Examiner no longer relies, the
Appellants argue:
Thus, these references (along with the cited references now
applied) show that the accepted wisdom in the art was not to
utilize a configuration with the first and second RF power applied
to a bottom electrode and two separate switches respectively
connecting an upper electrode to ground or to a DC supply.
Indeed, the preference in the art seems to be that of 1) directly
grounding the upper electrode or 2) applying an RF bias (not a
DC bias) to the upper electrode ....
App. Br. 29.
The Appellants' argument is without persuasive merit. The mere fact
that the references cited by the Appellants differ from the claimed invention
does not render the obviousness combination set forth by the Examiner
inapt. Cf In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004) ("The prior
art's mere disclosure of more than one alternative does not constitute a
teaching away from any of the[] [disclosed] alternatives .... "). The
Appellants have not persuasively argued that those references would have
discouraged a person of ordinary skill from pursuing the Examiner's
proposed combination. As set forth above, Arai teaches that it was known to
use first and second RF power sources applied to the lower electrode for the
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same or similar purposes as disclosed by the Appellants' Specification. The
Examiner finds that Kholodenko teaches a three-pole switch connected to an
upper electrode that, in combination with Zhao' s upper electrode and DC
bias, appears to be functionally equivalent to the two separate switches of
claim 21. The Examiner further finds, and the Appellants do not
persuasively dispute, that Zhao teaches that the upper electrode is DC biased
or grounded. Ans. 5. The Appellants have not shown that Koshiishi,
Kholodenko, or Arai require direct grounding of the upper electrode.
Kholodenko expressly teaches a floating state. See Kholodenko Fig. 5.
Both Zhao and Koshiishi teach applying a DC bias to the upper electrode.
Furthermore, the Appellants proffer no evidence on this record what one of
ordinary skill in the art at the time of the invention understood or accepted
based on the art as a whole. Thus, we are not persuaded that the art as a
whole teaches away from the configuration of claim 21.
5. The Appellants argue that their invention results in a "change in
the[] respective functions" of the prior art elements because Kholodenko
concerns cleaning, while claim 21 concerns etching. See App. Br. 30-32
(emphasis omitted).
We are not persuaded by that argument. The Appellants do not
persuasively argue that claim 21 results in a different function for any
individual element of the prior art. As disclosed in both the prior art and the
Appellants' Specification, the DC bias affects plasma density, and the RF
power supplies generate plasma and affect ion movement. Each individual
element of claim 21 is being used in a way that is, as set forth above, taught
or suggested by the prior art whether used for etching or for cleaning.
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While if 22 of Kholodenko concerns cleaning the chamber, it also
expressly teaches that the etch rate can be enhanced by use of a switch to
select certain states. Further, on this record, we are not persuaded that the
disclosed cleaning process differs in any material way to a sufficient degree
that a person of ordinary skill in the art would not have been motivated to
combine the references as proposed by the Examiner. On the contrary,
Kholodenko expressly suggests that switching between grounded and
floating impacts etching. Kholodenko if 22; see also Spec. 31:20-37:7
(discussing etching and cleaning).
6. The Appellants argue that the claimed invention would not have
been obvious in view of the prior art because the prior art includes "many
possible combinations of ... power supplies and switches," and a person of
ordinary skill "would have to sort through all the possible switch setting[ s]
in order to arrive at the claimed control program." See App. Br. 33.
We are not persuaded by that argument. As set forth above, the prior
art discloses and motivates the use of a DC-biased upper electrode and a
lower electrode connected to both a high frequency RF power supply and a
low frequency RF power supply. It further teaches the use of a switch that
appears to be functionally equivalent to the Appellants' first and second
switches when combined with Zhao' s DC-biased upper electrode. The
switch appears to have only three states: power (without grounding),
ground, or float. The Examiner provides reasonable bases for combining the
prior art as proposed to achieve a plasma processing apparatus that renders
obvious the plasma processing apparatus of claim 21, and the Appellants do
not persuasively refute the Examiner's rationale. In light of the teachings of
the prior art, on this record, we are not persuaded that the possibilities are so
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numerous that the Examiner erred in concluding that the combination relied
on supports a conclusion of obviousness. Cf Merck & Co. v. Biocraft Labs.,
874 F.2d 804, 807 (Fed. Cir. 1989) ("That the [prior art] patent discloses a
multitude of effective combinations does not render any particular
formulation less obvious.").
* * *
In summary, we have carefully considered the arguments presented by
the Appellants. On this record, we are not persuaded of reversible error in
the Examiner's rejection of claim 21.
CONCLUSION
We AFFIRM the Examiner's rejections of claims 21-24.
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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