Ex Parte Liu et al

Patent Trial and Appeal Board

Sep 13, 2017

13189992 (P.T.A.B. Sep. 13, 2017)

United States Patent and Trademark Office
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/189,992 07/25/2011 ZHENDONG LIU 15555USA 1311
55649 7590 09/15/2017
Moser Taboada / Applied Materials, Inc.
1030 Broad Street
Suite 203
Shrewsbury, NJ 07702
EXAMINER
WITTENBERG, STEFANIE S
ART UNIT PAPER NUMBER
1756
NOTIFICATION DATE DELIVERY MODE
09/15/2017 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):
ataboada@mtiplaw.com
docketing@mtiplaw.com
llinardakis @ mtiplaw. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ZHENGDONG LIU, YONG CAO, XIAMIN TANG,
SRINIVAS GANDIKOTA, THANH NGUYEN, and
MUHAMMAD RASHEED1
Appeal 2016-002043
Application 13/189,992
Technology Center 1700
Before MARK NAGUMO, CHRISTOPHER C. KENNEDY, and
MONTE T. SQUIRE, 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 12—16 and 19—21. We have jurisdiction under
35 U.S.C. § 6(b). We AFFIRM.
BACKGROUND
The subject matter on appeal relates to physical vapor deposition
(PVD) processes. E.g., Claim 12. Claim 12 is reproduced below from page
1 According to the Appellants, the real party in interest is Applied Materials,
Inc. App. Br. 3.
Appeal 2016-002043
Application 13/189,992
14 (Claims Appendix) of the Appeal Brief (emphasis added to key
limitations):
12. A method of processing a substrate in a physical vapor
deposition (PVD) chamber, the method comprising:
providing a process gas having at least some ionic species into
the PVD chamber;
applying a DC power to a target disposed above a substrate to
direct the ionic species towards the target;
rotating a magnetron above the target, the magnetron having an
inner closed loop magnetic pole and an outer closed loop
magnetic pole, wherein the inner closed loop magnetic pole is
disposed within the outer closed loop magnetic pole, and wherein
an unbalance ratio of a magnetic field strength of the outer
closed loop magnetic pole to a magnetic field strength of the
inner closed loop magnetic pole is less than 1;
sputtering metal atoms from the target using the ionic species;
depositing a first plurality of metal atoms on the substrate;
applying an RF power to re-sputter at least a portion of the
deposited first plurality of metal atoms using the ionic species;
and
forming a layer on the substrate by applying the DC power and
the RF power for a desired time period, wherein the layer has a
thickness uniformity of less than about 2 percent and a resistivity
of less than about 10 pOhm-cm.
REJECTIONS ON APPEAL
1. Claims 12, 13, 15, 16, and 19—21 stand rejected under 35 U.S.C.
§ 103(a) as unpatentable over Wada (US 6,440,282 Bl, issued Aug. 27,
2002) in view of Fu (US 2010/0105203 Al, published Apr. 29, 2010)
(“Fu ’203”).
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Application 13/189,992
2. Claims 15, 16, 20, and 21 stand rejected under 35 U.S.C. § 103(a)
as unpatentable over Wada in view of Fu ’203, further in view of Fu (US
2005/0051424 Al, published Mar. 10, 2005) (“Fu ’424”).
3. Claim 14 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Wada in view of Fu ’203, further in view of Ventzek (US 6,165,567,
issued Dec. 26, 2000).
ANALYSIS
Although the Appellants include separate sections in the Appeal Brief
for the different grounds of rejection, see App. Br. 6—12, the substantive
arguments are directed only to claim 12. We select claim 12 as
representative of the rejected claims, and the remaining claims on appeal
will stand or fall with claim 12.
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 Final Action, and in the Examiner’s Answer. See generally Final
Act. 2—14; Ans. 2—17.
The Examiner finds that Wada teaches a method comprising each
step of the method of claim 12, including application of an RF power, except
that (1) Wada does not explicitly disclose that application of the RF power
results in re-sputtering, and (2) Wada does not recite the resistivity of the
formed layer. Final Act. 3—6.
Concerning (1) re-sputtering caused by application of RF power, the
Examiner finds that Fu ’203 teaches that the application of RF power to a
deposited layer results in re-sputtering of material. Id. at 4; Ans. 16.
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Concerning (2) the resistivity of the formed layer, the Examiner finds
that, because the method of Wada as modified by Fu ’203 is the same as the
claimed method, “this is considered to be an intrinsic property . . . absent
any clear and convincing evidence and/or arguments to the contrary.” Final
Act. 5; cf. 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.”); In re Best, 562 F.2d 1252, 1255 (CCPA 1977) (“Where, as here,
the claimed and prior art products are identical or substantially identical, or
are produced by identical or substantially identical processes, 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.”).
Additionally, the Examiner finds that both Wada and Fu ’203 express
concern for the resistivity of the deposited layer, and that both “are directed
towards semiconductor and/or components including transistors, capacitors
and resistors that include highly conductive material (i.e. low resistivity).”
Id. at 5, 12—14. The Examiner also finds that the claimed properties of
uniformity and resistivity “are a result of performing the claimed method,
and more particularly the power and time period of application.” Id. at 13.
The Examiner finds that the combination of Wada and Fu ’203 “is capable
of resulting in a film of such resistivity since the combination discloses each
and every method step claimed,” and that a person of ordinary skill in the art
would have been motivated to achieve low resistivity, which “result[s] in
improved reliability of finished devices,” according to Fu ’203. Id. at 12—
13.
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Application 13/189,992
With respect to the claimed thickness uniformity of less than about
2%, the Examiner finds that Wada teaches that its process results in a
thickness uniformity of 5% or less, which encompasses the claimed range.
Id. at 4. As with resistivity, discussed above, the Examiner finds that
uniformity is “a result of performing the claimed method, and more
particularly the power and time period of application.” Id. at 13. The
Examiner suggests that a person of ordinary skill in the art would have been
capable of operating the process of Wada as modified by Fu ’203 to achieve
thickness uniformity of 5% or less, as taught by Wada. Id. at 4, 13—14.
In view of those and other findings, the Examiner concludes that the
subject matter of claim 12 would have been obvious in view of Wada and
Fu ’203.
The Appellants do not persuasively dispute the Examiner’s
determination that the process of Wada and Fu ’203 comprises every step of
claim 12. Although they argue that Wada prefers an unbalance ratio of the
outer loop to the inner loop of greater than 1, they expressly acknowledge
that “Figure 9 in Wada does depict an embodiment where the inner magnet
band can have a higher magnetic flux than the outer magnet band.” App. Br.
7; see also Wada Fig. 9, 17:35—41, 18:13—18. Indeed, Wada explicitly
teaches that either embodiment (unbalance ratio greater than or less than 1)
“can be used in the sputter reactor of the present invention.” Id. at 18:13—14.
We recognize that Wada appears to prefer an unbalance ratio greater
than 1, and that Wada teaches that the use of such an unbalance ratio “is
more suitable for increasing the electron density of the plasma.” Id. at
18:15—18; App. Br. 7. However, the Appellants identify no teaching or
suggestion in Wada that an unbalance ratio of less than 1 would have been
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Application 13/189,992
considered unsuitable for obtaining a useful electron density, or considered
otherwise unsuitable for achieving the desired thickness uniformity of 5% or
less that is taught by Wada. See Wada at 23:65—24:1; cf. In re Mouttet, 686
F.3d 1322, 1334 (Fed. Cir. 2012) (“[J]ust because better alternatives exist in
the prior art does not mean that an inferior combination is inapt for
obviousness purposes.”); DePuy Spine, Inc. v. Medtronic Sofamor Danek,
Inc., 567 F.3d 1314, 1327 (Fed. Cir. 2009) (“A reference does not teach
away, however, if it merely expresses a general preference for an alternative
invention but does not criticize, discredit, or otherwise discourage
investigation into the invention claimed.” (internal quotation marks
omitted)). On the contrary, and as noted above, Wada expressly teaches that
magnetrons having an unbalance ratio of less than 1 (i.e., that shown by
Figure 9) “can be used in the sputter reactor of the present invention.” Id. at
18:13—18. In the Final Action, the Examiner finds that Wada “nowhere
excludes the teaching of the inner magnetic strength greater than the outer
magnetic strength from the thickness result. Thus, the thickness uniformity
disclosed in Wada . . . may be applicable to any scenario disclosed in the
teachings including the inner magnetic strength greater than the outer
magnetic strength.” Final Act. 11. The Appellants do not persuasively
challenge that finding or otherwise identify error in it.
The Appellants’ argument that Fu ’424 also prefers unbalance ratios
of greater than 1 is likewise unpersuasive. See App. Br. 7—8.2 As noted
2 In their citations, the Appellants do not distinguish between Fu ’203, which
is relied on by the Examiner in Rejection 1, and Fu ’424, which is not. See
App. Br. 7—8 (referencing “Fu.”). However, the paragraphs that the
Appellants cite make clear that the Appellants are referencing Fu ’424. See
App. Br. 7—8 (citing || 56, 63, and 101, which do not exist in Fu ’203).
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above, the Appellants concede that Wada discloses an embodiment that
teaches or suggests the unbalance ratio of claim 12. The fact that Fu ’424,
which the Examiner does not rely on in Rejection 1, discloses embodiments
that do not fall within the scope of the claimed unbalance ratio is not
persuasive of reversible error in the rejection. Cf. Mouttet, 686 F.3d at 1334.
Nor is the Appellants’ reliance on Figure 19 of Wada persuasive. See
App. Br. 8. Figure 19 is a plot of Rs uniformity on the y-axis against
magnetic flux imbalance on the x-axis, and it shows that Rs uniformity
decreases as magnetic flux imbalance increases from about 1.3 to about 2.0.
See Wada Fig. 19. The Appellants rely on Figure 19 to suggest that uniform
bottom coverage would decrease at unbalance ratios of less than 1,
indicating that unbalance ratios of less than 1 are undesirable. See App.
Br. 8.
As the Examiner explains in the Final Action:
Figure 19 is a plot of sheet resistance uniformity to the magnetic
flux imbalance, thus the sheet resistance values are not directly
illustrated in this figure, and instead the uniformity of the sheet
resistance is plotted for analysis. Thus, figure 19 does not
provide evidence for or against a particular value of sheet
resistance, rather it provides the uniformity of sheet resistance.
Final Act. 12—13. In the Appeal Brief, the Appellants do not address or
otherwise respond to those findings. See App. Br. 8.
Moreover, the Examiner determines that “even if a [thickness
uniformity] value could be obtained by figure 19, this figure does not
provide any data or evidence for the scenario in which the inner magnetic
strength is greater than the outer magnetic strength” because no data is
provided for magnetic flux imbalances of less than 1. Final Act. 13. The
Examiner finds that “[o]ne of ordinary skill in the art would recognize that
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Application 13/189,992
the ‘inverse’ unbalanced magnetron [i.e., that of Figure 9, having an
unbalance ratio of less than 1] may result in varying results once the ratio is
less than 1The Appellants do not address or otherwise respond to those
findings, see App. Br. 8, which are consistent with Wada’s teaching that
unbalance ratios of both greater than 1 and less than 1 are suitable for use
with its invention. Accordingly, on this record, we are not persuaded that
Figure 19 of Wada indicates reversible error in the Examiner’s rejection.
Finally, with respect to the claimed resistivity, the Appellants argue
that Fu ’203’s disclosure of reducing line resistivity to increase reliability of
finished devices “does not teach or make obvious forming a layer on the
substrate having a resistivity of less than about 10 pOhm-cm. Furthermore,
regardless of whether or not it may be desirous to reduce resistivity to less
than about 10 pOhm-cm in Fu, nothing in Fu indicates that it is possible to
do so.” App. Br. 9.
That argument is not persuasive because it does not address the
Examiner’s rationale. While the Examiner does find that Fu ’203 suggests
the desirability of low resistivities, the Examiner does not find that Fu ’203
alone teaches or suggests the claimed resistivity. See Final Act. 5—6.
Instead, the Examiner finds that, because the steps of the process of Wada as
modified by Fu ’203 are the same as the steps of the claimed process, the
claimed resistivity “is considered to be an intrinsic property resulting from
following the method steps taught by [the prior art].” Id. at 5. The
Appellants do not address that rationale or otherwise attempt to show error
in it. See In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011) (explaining that,
even if the examiner had failed to make a prima facie case, the Board would
not have erred in framing the issue as one of reversible error because “it has
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long been the Board’s practice to require an applicant to identify the alleged
error in the examiner’s rejections”).
Moreover, and as noted above, the Examiner finds that the claimed
properties of thickness uniformity and resistivity “are a result of performing
the claimed method, and more particularly the power and time period of
application.” Id. at 13. The Examiner also finds that the process of Wada
and Fu ’203 “is capable of resulting in a film of [the claimed] resistivity
since the combination discloses each and every method step claimed.” Id. at
13. In the Reply Brief, the Appellants agree with the Examiner that process
parameters such as time period for applying power and the amount of power
applied may affect whether the claimed resistivity is achieved, but they do
not argue that controlling those process parameters to achieve the claimed
resistivity (which the Examiner finds is desirable in light of Fu ’203’s
teaching that lower resistivities result in increased reliability, see Final Act.
4—5) would have been beyond the ordinary level of skill in the art. See
Reply Br. 3.
On the record before us, we are not persuaded of reversible error in
the Examiner’s rejection of claim 12. Accordingly, we affirm the rejection.
CONCLUSION
We AFFIRM the Examiner’s rejections of claims 12—16 and 19—21.
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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