Ex Parte Hoffman et al

Patent Trial and Appeal Board

Apr 28, 2017

12077067 (P.T.A.B. Apr. 28, 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.
12/077,067 03/14/2008 Daniel J. Hoffman 013161 4633
USA/MDP/COPPER/CRO
26185 7590 05/02/2017
FISH & RICHARDSON P.C. (APPLIED MATERIALS)
P.O. BOX 1022
MINNEAPOLIS, MN 55440-1022
EXAMINER
BERMAN, JASON
ART UNIT PAPER NUMBER
1756
NOTIFICATION DATE DELIVERY MODE
05/02/2017 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):
PATDOCTC@fr.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte DANIEL J. HOFFMAN, KARL M. BROWN,
YING RUI, and JOHN PIPITONE
Appeal 2016-001696
Application 12/077,067
Technology Center 1700
Before JEFFREY B. ROBERTSON, GEORGE C. BEST, and
BRIAN D. RANGE, Administrative Patent Judges.
BEST, Administrative Patent Judge.
DECISION ON APPEAL
The Examiner finally rejected claims 1, 4—11, and 14—22 of
Application 12/077,067 under 35 U.S.C. § 103(a) as obvious and also finally
rejected claim 22 under 35 U.S.C. § 112,14. Final Act. (November 28,
2014). Appellants1 seek reversal of these rejections pursuant to 35 U.S.C.
§ 134(a). We have jurisdiction under 35 U.S.C. § 6.
For the reasons set forth below, we REVERSE.
1 Applied Materials, Inc. is identified as the real party in interest. Appeal
Br. 1.
Appeal 2016-001696
Application 12/077,067
BACKGROUND
The ’067 Application is directed to a method for plasma enhanced
physical vapor deposition (PEPVD) of metal films onto semiconductor
wafers having features with sizes of 22 nm or less. Spec. 11. In particular,
Appellants’ claimed method is said to provide a nearly isotropic velocity
distribution of neutral species and a predominantly vertical iron velocity
distribution at the wafer surface. Id. ^ 13.
Claim 1 is representative of the ’067 Application’s claims and is
reproduced below from the Claims Appendix of the Appeal Brief:
1. A method of performing physical vapor deposition
on a workpiece having device feature sizes of 22 nm or smaller
in a reactor chamber, comprising:
providing a target comprising a metallic element and
having a surface facing the workpiece, and establishing a target-
to-workpiece gap less than one fifth of a diameter of said
workpiece;
introducing a carrier gas into the chamber and maintaining
gas pressure in the chamber above a threshold pressure at which
mean free path is less than 5% of said gap;
applying RF plasma source power from a VHF generator
to said target through an impedance match connected to said
target to generate a capacitively coupled plasma at said target,
said VHF generator having a frequency exceeding 30 MHz; and
extending said plasma across said gap to said workpiece
by providing through said workpiece a first VHF ground return
path at the frequency of said VHF generator.
Appeal Br. 12.
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Appeal 2016-001696
Application 12/077,067
REJECTIONS
On appeal, the Examiner maintains the following rejections:
1. Claim 22 is rejected under 35 U.S.C. § 112,14 as being of improper
dependent form for failing to further limit the subject matter of the
claim from which it depends. Final Act. 2—3.
2. Claims 1, 4—11, and 14—22 are rejected under 35 U.S.C. § 103(a) as
unpatentable over the combination of Brown,2 Kobayashi,3 and
Tonucci.4 Final Act. 4—10.
DISCUSSION
Rejection 1. Claim 22 of the ’067 Application reads:
Claim 22: The method of Claim 1 further comprising
limiting D.C. power on said target below a threshold at which
deposition to a desired thickness requires on the order of 30
seconds.
Appeal Br. 16.
The Examiner rejected claim 22 pursuant to 35 U.S.C. § 112,14.
Final Act. 2. The Examiner explained the basis for the rejection:
Claim 22 requires limiting DC power on said target below
a threshold at which deposition to a desired thickness requires on
the order of 30 seconds. Because the claim doesn’t limit the
‘desired thickness,’ any thickness can be called the desired
thickness and therefore any thickness obtained on the order of 30
seconds can be called the desired thickness. Because of the lack
of limitation on the ‘desired thickness’, and because DC power
can be used and the resulting thickness at 30 seconds is the
2 US 2006/0073283 Al, published April 6, 2006.
3 US 5,439,574, issued August 8, 1995.
4 US 5,855,716, issued January 5, 1999.
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Appeal 2016-001696
Application 12/077,067
‘desired thickness’, claim 22 does not further limit its parent
claim.
Final Act. 3.
We reverse this rejection. Properly understood, claim 22 limits the
amount of DC power supplied to the target to that which allows formation of
a layer with a predetermined thickness in a time on the order of 30 seconds.
Claim 22 limits the scope of claim 1 because the amount of DC power
supplied to the target could be such that the formation of the layer of
predetermined thickness occurs over a period of time not recited in claim 1.
Depending on the proper interpretation of the limitation “requires on the
order of 30 seconds”—an issue which we need not and do not address at this
time—deposition of a layer of predetermined thickness need not require a
time “on the order of 30 seconds” in claim 1. Thus, claim 22 further limits
the scope of claim 1.
Rejection 2. The Examiner rejected claims 1, 4—11, and 14—22 as
unpatentable over the combination of Brown, Kobayashi, and Tonucci.
Final Act. 4.
For the purpose of this opinion, we need only consider the limitation
“establishing a target-to-workpiece gap less than one fifth of a diameter of
said workpiece.” This language appears in both of the independent claims
before us. See claims 1 and 16. In rejecting claims 1 and 16, the Examiner
found that Kobayashi describes or suggests this claim limitation. See Final
Act. 5 (claim 1), 8 (claim 16). In particular, the Examiner found that
“Kobayashi discloses the use of relatively high pressure with a small target
to substrate distance with relation to substrate size (col 6 lines 40-45:
205mm substrate, 60mm substrate size; col 5 line 14: several tens of mTorr
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Appeal 2016-001696
Application 12/077,067
pressure; figure 6: gap to substrate ratio of 1/3-1/5).” Id. at 5; see also id. at
8.
As Appellants point out, the Examiner’s finding that Kobayashi’s
Figure 6 describes the use of a gap to substrate ratio is erroneous. See
Appeal Br. 4. In fact, Figure 6 shows the variability of the thickness of the
positive layer is a function of the ratio of the target-substrate gap distance to
the target diameter. Kobayashi col. 3,11. 2—6. The independent claims limit
the ratio of the target-substrate gap distance to the substrate diameter. Thus,
the factual basis set forth in the Final Action is erroneous.
In the Examiner’s Answer, the Examiner reasons that this erroneous
finding does not constitute reversible error because the entirety of
Kobayashi’s disclosure suggests the use of a gap distance to substrate
diameter ratio of approximately one fifth:
Figure 6 of Kobayashi illustrates a data line of the gap to
target ratio corresponding to thickness uniformity (y-axis
'thickness distribution percent' inversely corresponding to
thickness uniformity - a higher percent being less uniform
thickness). Figure 6 of Kobayashi illustrates the data trend
extending past the 1/5 point to lower ratios for both trend lines,
the Ar/N = 0/1 [dotted line] and ‘Ti’ [only - solid line] trend line
increasing in thickness uniformity as the ratio is lower [moving
towards the 0,0 comer of the plot]. Therefore, it would be
obvious to one of ordinary skill in the art that increased thickness
uniformity (the goal of Kobayashi - see Abstract and col 1 lines
16-45, discussing objectives of obtaining increased uniformity
when depositing films on a substrate) can be obtained by
lowering the gap ratio [i.e., the ratio of the target-substrate gap
distance to the target diameter], as illustrated in figure 6.
Therefore, although the ‘point’ at 1/5 on figure 6 may only
correspond to a ‘0.29’ ratio as related to the ‘0.2’ required by the
claims, figure 6 would lead one of ordinary skill in the art to
obtain greater uniformity by further lowered the gap value
(moving further left on the x-axis of figure 6), and therefore
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Appeal 2016-001696
Application 12/077,067
obtain values below the ‘0.29’ value, including a ‘0.2’ value as
required by the instant claims.
Answer 10—11 (italicized text added).
The Examiner’s reasoning is not supported by sufficient rational
underpinnings. Although the Examiner correctly points out that, for some
materials, Kobayashi’s Figure 6 suggest the use of a target-substrate gap
distance to target diameter ratio that is less than one fifth, the Examiner does
not explain why a person having ordinary skill in the art would have chosen
to decrease the value of that ratio by decreasing the gap distance rather than
increasing target size as disclosed in Kobayashi. In the absence of such an
explanation, we cannot affirm the Examiner’s rejection. See In re Kahn, 441
F.3d 977, 988 (Fed. Cir. 2006) (“[R]ejections on obviousness grounds
cannot be sustained by mere conclusory statements; instead, there must be
some articulated reasoning with some rational underpinning to support the
legal conclusion of obviousness.”).
We, therefore, reverse the Rejection of claims 1, 4—11, and 14—22.
CONCLUSION
For the reasons set forth above, we reverse the § 112,14 rejection of
claim 22. We also reverse the rejection of claims 1, 4—11, and 14—22 under
§103.
REVERSED
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