Ex Parte Marakhtanov et al

Patent Trial and Appeal Board

Aug 28, 2018

13227404 (P.T.A.B. Aug. 28, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/227,404 09/07/2011
119049 7590 08/30/2018
MPG, LLP and Lam Research Corp.
Albert Penilla
710 Lakeway Drive
Suite 200
Sunnyvale, CA 94085
FIRST NAMED INVENTOR
Alexei Marakhtanov
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.
LAM2P714 5410
EXAMINER
CROWELL, ANNA M
ART UNIT PAPER NUMBER
1716
NOTIFICATION DATE DELIVERY MODE
08/30/2018 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):
lamptomail@mpiplaw.com
mpdocket@mpiplaw.com
eofficeaction@appcoll.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ALEXEI MARAKHTANOV, RAJINDER DHINDSA,
ERIC HUDSON, and ANDREW D. BAILEY III
Appeal2017-010183
Application 13/227 ,404
Technology Center 1700
Before ADRIENE LEPIANE HANLON, JEFFREY R. SNAY, and
JENNIFER R. GUPTA, Administrative Patent Judges.
SNAY, Administrative Patent Judge.
DECISION ON APPEAL 1
Appellants2 appeal under 35 U.S.C. § 134(a) from the Examiner's
decision rejecting claims 1-10, 18-25, and 27-29. We have jurisdiction
under 35 U.S.C. § 6(b ).
We affirm.
1 We refer to the Specification ("Spec.") filed September 7, 2011; Final
Office Action ("Final Act.") dated November 5, 2015; Appellants' Appeal
Brief ("App. Br.") filed March 25, 2016; Examiner's Answer ("Ans.") dated
October 20, 2016; and Appellants' Reply Brief ("Reply Br.") filed
December 20, 2016.
2 Appellants identify Lam Research Corporation as the real party in interest.
App. Br. 3.
Appeal2017-010183
Application 13/227,404
BACKGROUND
The subject matter on appeal relates to dielectric etching of a
semiconductor device. Spec. 1. Manufacture of integrated circuits involves
immersing silicon substrates in chemically-reactive plasmas. Id. According
to the Specification, pulsed RF plasma techniques suffer drawbacks related
to afterglow, which involves escape of electrons to chamber walls during the
RF OFF period. Id. at 3--4. Re-striking the plasma after the afterglow is
extinguished requires high RF voltage levels. Id. at 4. Appellants address
the foregoing issues by providing a dual chamber configuration, in which a
continuous wave plasma source is provided in an upper chamber and a
pulsed wave plasma source is provided in the lower chamber. Id. at 14.
Electrons flow from the upper plasma to the lower chamber to assist in re-
striking. Id. Claim 1 is illustrative:
1. A wafer processing apparatus with a top chamber
and a bottom chamber, comprising:
a plate separating the top chamber and the bottom
chamber, the plate having a plurality of holes that enable a flow
of species from the top chamber to the bottom chamber during
operation;
a continuous wave (CW) controller operable to set a
voltage and a frequency for a first radio frequency (RF) power
source coupled to a top electrode in the top chamber, the first
RF power source configured to provide a continuous RF power
during operation of the chamber;
a pulse controller operable to set voltage, frequency, ON-
period duration, and OFF-period duration for a pulsed RF
signal generated by a second RF power source coupled to a
bottom electrode in the bottom chamber, wherein a bottom
plasma is stricken in the bottom chamber during the ON period,
wherein a potential of the bottom plasma decays during the
OFF period until the potential reaches a value of substantially
zero; and
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Application 13/227,404
a system controller configured to set parameters for the
top chamber and parameters for the bottom chamber to regulate
the flow of species from the top chamber to the bottom chamber
through the plate during the ON period and to regulate the flow
of species during the OFF period, the parameters for the top
chamber including the voltage and frequency for the first RF
and the parameters for the bottom chamber including the
voltage, frequency, ON-period duration, and OFF-period
duration for the pulsed RF signal, wherein the CW controller
implements a setting for the first RF power source
independently of a setting by the pulse controller for the second
RF power source, wherein by regulating the flow of species the
system controller is operable to regulate a negative-ion etching
in the bottom chamber and to regulate positive charge on a
wafer surface in the bottom chamber during afterglow in the
OFF period, and wherein the CW controller regulates the flow
of species to assist in re-striking the bottom plasma in the
bottom chamber during the ON period by regulating flow of
electrons from the top chamber to the bottom chamber.
App. Br. 20-21 (Claims Appendix).
REJECTIONS
I. Claims 1-6, 9, 18, 19, 21-25, and 27-29 stand rejected under
35 U.S.C. § I03(a) as unpatentable over Paterson, 3 Loewenhardt, 4 and
Koshimizu. 5
II. Claim 7 stands rejected under 35 U.S.C. § I03(a) as unpatentable over
Paterson, Loewenhardt, Koshimizu, and Hanawa. 6
3 US 2008/0178805 Al, published July 31, 2008 ("Paterson").
4 US 2004/0221958 Al, published November 11, 2004 ("Loewenhardt").
5 US 6,214,162 B 1, issued April 10, 2001 ("Koshimizu").
6 US 7,695,590 B2, issued April 13, 2010 ("Hanawa").
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Application 13/227,404
III. Claim 8 stands rejected under 35 U.S.C. § I03(a) as unpatentable over
Paterson, Loewenhardt, Koshimizu, and Chen. 7
IV. Claims 10 and 20 stand rejected under 35 U.S.C. § I03(a) as
unpatentable over Paterson, Loewenhardt, Koshimizu, and Ishizuka. 8
OPINION
We review the appealed rejection for error based upon the issues
identified by Appellants and in light of the arguments and evidence
produced thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010)
(precedential), cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed.
Cir. 2011) ("[I]t has long been the Board's practice to require an applicant to
identify the alleged error in the examiner's rejections .... "). After
considering the evidence presented in this Appeal and each of Appellants'
arguments, we are not persuaded that Appellants identify reversible error.
Thus, we affirm the Examiner's rejections for the reasons expressed in the
Final Office Action and Answer. We add the following primarily for
emphasis.
Rejection I
With regard to Rejection I, Appellants argue the claims as a group,
with the exception of claims 23 and 24 which are argued separately. App.
Br. 6-15. We select claim 1 as representative of the grouped claims.
Claims 2-6, 9, 18, 19, 21, 22, 25, and 27-29 stand or fall with claim 1.
Claims 23 and 24 are separately addressed.
7 US 2004/0025791 Al, published February 12, 2004 ("Chen").
8 US 5,476,182, issued December 19, 1995 ("Ishizuka").
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Application 13/227,404
Claim 1
The Examiner finds that Paterson discloses a wafer processing
apparatus that includes all of the structural elements recited in claim 1,
including separately controlled plasma generators respectively associated
with an upper and lower processing chamber, except that Paterson does not
disclose a pulse controller for operating the lower plasma generator. Final
Act. 3. The Examiner finds that each of Loewenhardt and Koshimizu teach
certain advantages associated with use of a pulsed plasma in wafer
processing, and determines on that basis that it would have been obvious to
provide a pulse controller for operating Paterson's lower chamber plasma
generator. Id. at 3--4.
Appellants argue that modifying Paterson's lower plasma generator
from continuous to pulsed would have required Paterson's chamber to be
redesigned. App. Br. 7. See also id. at 8 ("the operation of the chamber
would be different and the chamber would have to be re-engineered").
However, Appellants do not point to evidence or credible technical
reasoning to support the contention that the proposed modification would
have necessitated a redesign of Paterson's chamber. Nor do Appellants
point to any structural difference between Paterson's chamber and that
which is set forth in the claims. As such, Appellants' argument is not
persuasive of reversible error.
Appellants also argue that none of the relied-upon references
identifies the problem addressed by the claimed invention-namely,
"regulating the OFF period in the chamber and in regulating the flow of
species." Id. at 8-9. Relatedly, Appellants argue that the references fail to
disclose the recited "system controller configured to set parameters for the
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Appeal2017-010183
Application 13/227,404
top chamber and parameters for the bottom chamber to regulate the flow of
species from the top chamber to the bottom chamber." Id. at 11-14.
We find these arguments unpersuasive of reversible error. Other than
the above-noted contention that providing Paterson's lower chamber plasma
source with a pulse controller would require re-design of the chamber,
Appellants do not dispute the Examiner's findings that Loewenhardt and
Koshimizu provide a reason to use pulse-controlled plasma. See App. Br. 8
("The Examiner has identified that the motivation to pulse bias power
sources is to control etch bias, sheath, etc., but the person skilled in the art
would not be motivated to do the combination because the operation of the
chamber would be different and the chamber would have to be re-
engineered. "). That the prior art has a different reason or motivation to
provide Paterson with a pulse controller is of no moment as long as there is a
sufficient reason to make the combination. See In re Kemps, 97 F.3d 1427,
1430 (Fed. Cir. 1996). ("[T]he motivation in the prior art to combine the
references does not have to be identical to that of the applicant to establish
obviousness."). Regarding the claimed system controller, the Examiner
finds that Paterson provides a system controller which is configured to
control operating parameters of both the upper and lower chamber plasma
sources, including control of voltage and frequency. Final Act. 3. The
Examiner also finds that Loewenhardt and Koshimizu similarly teach system
control of the pulsed plasma source parameters, including voltage,
frequency, and on/off duration. Id. at 3--4. Appellants' state in the
Specification that flow of species between chambers is achieved by
providing a system controller configured to control voltage, frequency, and
on/off duration of the plasma generators. Spec. 6. As such, Appellants do
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Application 13/227,404
not present persuasive evidence of any structural or operational difference
between the claimed system controller and that of the prior art.
Claims 2 3 and 2 4
With regard to claim 23, Appellants argue that the relied-upon
references are "silent with reference to requiring a lower [ re-striking]
pressure when the flow of electrons is regulated." App. Br. 15. Claim 23,
however, does not require use of a particular pressure when re-striking.
Rather, the claim recites that "the bottom plasma can be stricken at a lower
bottom chamber pressure." (Emphasis added). Appellants do not present
persuasive evidence that the apparatus suggested by Paterson, Loewenhardt,
and Koshimizu would not have been capable of performing in the same
manner by allowing re-striking at a lower chamber pressure.
Regarding claim 24, Appellants present the same argument with
regard to the speed at which lower chamber plasma is stricken. That
argument is not persuasive for the reasons set forth above in connection with
claim 23.
For the foregoing reasons, Appellants' arguments are not persuasive
of reversible error. Rejection I is sustained. 9
Re} ections II and III
With regard to Rejections II and III, Appellants solely rely on the
same arguments presented and discussed above in connection with
9 Appellants raise new arguments in the Reply Brief concerning claims 1, 7,
and 8. See Reply Br. 3-7, 9, 10. Appellants have not shown good cause
explaining why these arguments were not raised in the Appeal Brief.
Therefore, these arguments have been waived. See 37 C.F.R. § 4I.41(b)(2).
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Application 13/227,404
Rejection I. App. Br. 15-16. Having found those arguments unpersuasive,
Rejections II and III also are sustained.
Re} ection IV
Each of claims 10 and 20 recites that the top and bottom chambers are
"operable to have" a specified pressure during wafer processing. Appellants
challenge the Examiner's reliance on Ishizuka for its teaching of operating
pressures. App. Br. 17-18. However, Appellants do not identify any
particular structure associated with the recited operating pressures.
Applying the broadest reasonable interpretation to the term "operable," we
read the recitations in each of claims 10 and 20 as encompassing a capability
to operate at pressures within the recited ranges. Appellants do not argue
that Paterson's apparatus lacks such capability. Moreover, Paterson states
that chamber pressure can be controlled by operation of an evacuation valve,
and that pressure in the upper chamber will be greater than that of the lower
chamber. Paterson ,r,r 22, 29. On this record, we are not persuaded that the
pressure recitations in claim 10 or 20 require more than Paterson's capability
to regulate pressure.
For the foregoing reasons, Rejection IV also is sustained.
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Application 13/227,404
DECISION
The Examiner's decision rejecting claims 1-10, 18-25, and 27-29 is
affirmed.
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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