Ex Parte Zhang et al

Patent Trials and Appeals Board

Jan 8, 2019

14094921 - (D) (P.T.A.B. Jan. 8, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
14/094,921 12/03/2013
29050 7590 01/10/2019
Thomas Omholt
Patent Prosecution Agent
CABOT MICROELECTRONICS CORPORATION
870 NORTH COMMONS DRIVE
AURORA, IL 60504
Ke Zhang
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.
100563 3009
EXAMINER
DUCLAIR, STEPHANIE P.
ART UNIT PAPER NUMBER
1713
NOTIFICATION DATE DELIVERY MODE
01/10/2019 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):
CMC_PROSECUTION@CABOTCMP.COM
thomas_omholt@cabotcmp.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE
THE PATENT TRIAL AND APPEAL BOARD
Ex parte KE ZHANG, 1
Michael White, Tsung-Ho Lee, Steven Grumbine, and
Hon-Wu Lau
Appeal2018-001477
Application 14/094,921
Technology Center 1700
Before MARK NAGUMO, JAMES C. HOUSEL, and
DEBRA L. DENNETT, Administrative Patent Judges.
NAGUMO, Administrative Patent Judge.
DECISION ON APPEAL
Cabot ("Zhang") timely appeals under 35 U.S.C. § 134(a) from the
Final Rejection2 of all pending claims 1-5, 7, 9-12, 16, and 17. We have
jurisdiction. 35 U.S.C. § 6. We reverse.
1 The applicant under 37 C.F.R. § 1.46, and hence the appellant under
35 U.S.C. § 134, is the real party in interest, identified as Cabot
Microelectronics Corporation ("Cabot"). (Appeal Brief, filed 31 May 2017
("Br."), 1.)
2 Office Action mailed O 1 December 2016 ("Final Rejection"; cited as
"FR").
Appeal2018-001477
Application 14/094,921
A. Introduction 3
OPINION
The subject matter on appeal relates to chemical mechanical polishing
["CMP"] methods and compositions, particularly for nickel phosphorus
["NiP"] surfaces, which are said to be commonly used for rigid disks (hard
drives). (Spec. 1 [0001]-[0002].) Prior art CMP compositions for such uses
are said to comprise an abrasive, such as silica or alumina, a primary
oxidizing agent, such as hydrogen peroxide, and, in some embodiments, a
secondary oxidizing agent, typically a metal ion4 such as ferric ion.
(Id. at [0002].) The ferric ion catalyst is said to be capable of reversible
oxidation and reduction in the presence ofNiP and an oxidizing agent such
as hydrogen peroxide. (Id. at 4 [0018].) The prior art is also said to provide
chelating additives such as citrate and EDT A to complex the ferric ion and
to act to reduce the decomposition rate of the primary oxidizer (hydrogen
peroxide) and thus act as a "stabilizer." (Id. at 1-2 [0004].) The pH of these
prior art compositions is said to be above 2. 5 However, chelating agents
with high ferric ion binding constants are said to reduce the polishing
3 Application 14/094,921, CMP compositions and methods for polishing
nickel phosphorous surfaces, filed 03 December 2013. We refer to the
'"921 Specification," which we cite as "Spec."
4 The '921 Specification indicates that the art also refers to the metal ion as
a "metal catalyst" (Spec. 1 [0004], 1st sentence), and as a "polishing
accelerator" (id. at 2 [0004], penultimate sentence).
5 Spec. 2 [0004], discussing Keigo Ohashi, U.S. Patent No. 6,309,434 Bl
(2001 ). The '921 Specification also compares its results to Ohashi in
Example 4 (Spec. 11-12 [0035], including Table 7), as discussed infra.
2
Appeal2018-001477
Application 14/094,921
removal rates [ofNiP], which is contrary to the critical requirement for high
removal rates to maximize manufacturing throughput. (Id. at [0005].)
Zhang seeks patent protection for a CMP method in which the pH is
less than 1.5, the catalyst stabilizing agent is malonic acid [H2C(COOH)2] in
a certain range of concentration both in the solution and relative to the metal
ion, and glycine [H2NCH2COOH] as a nickel complexing agent. Such
compositions are said to "improve oxidizer stability without significantly
compromising NiP material removal rates for ferric ion-catalyzed CMP
slurries." (Id.)
The '921 Specification speculates that the Ni complexing agent "aids
in Ni removal by complexing with nickel ions formed during the polishing
process." (Id. at 4 [0017].) Support for this hypothesized role of glycine in
a low pH (pH 1.8) polishing process (in the absence of an iron catalyst as a
secondary oxidizing agent) is indicated in Example 1, Table 1, which shows
slurry S2 (glycine) providing the highest rate of removal
(RR= 17 .39 mg/min) of all Ni complexing agents (slurry S8 provides a
control without a nickel complexing agent, RR= 9.96 mg/min). (Spec. 8.)
As indicated in Table 2, the enhancing role of glycine continues with and
without iron catalyst. (Id. at 9.)
As shown in Table 5, high rates of removal ("RR") also are obtained
at low pH (pH 1.3) with glycine as a nickel complexing agent, but without
malonic acid as a catalyst stabilizer. (Id. at 10.) But, as shown in Figure 1
(not reproduced here), increased metal catalyst (Fe) concentration results in
decreased oxidizer (hydrogen peroxide) concentration with time if malonic
acid is not present as a catalyst stabilizer. (Id. at 9-10 [0033].)
3
Appeal2018-001477
Application 14/094,921
Example 3 provides a comparison of oxalic acid [(COOH)2] and
malonic acid as catalyst stabilizing agents in the presence of 100 ppm Fe and
0.6 w% glycine at pH 1.5. (Id. at 10-11 [0034].) As shown in Figure 2, not
reproduced here, oxalic acid ( dashed lines) provides better oxidative
stabilization than malonic acid (solid lines), "likely due to a stronger
complexation with iron." (Id. at 10 [0034].) However, as shown in
Figure 3, shown below,
,,,~------~---·············
. -
.
........................... • •• • muL , , '•"•"•"•",".".',•,•,•,•,•n••"'i'•• , ••••• •.•.•.•.•,•,•,•,•,•,•,•,•,•,•,•••••••••• ••••,•,•,",",",•,•,•,•,•,•,•,•,•,•,•,• • •, , , , • • ••",",",-,",","" h • • • •• • • •~~• • •, ,\\\'".",",",._ ...... h"."'F, .
"'"''""'"-.-.-.-.-.-.•.•••••••••·a,,•,ss"-.-.""-.-.-.•.•.•~,Ji,."JI"'"'-'•'•'•''''"''''"'·'·'"'' ... ,,, ... -.-.-. .. -.-.-.-.-.-..•.•.••• '•'•'•'''''''"'"""""""'-'"""""""
{Figure 3 shows the removal rate ("RR") with catalyst stabilizer: at t = 0, the
RR with malonic acid as the stabilizer, is higher than the control, while the
RR with oxalic acid as the stabilizer is lower than the control}
oxalic acid (solid lines) reduces the fresh pot removal rate (Day 0), relative
to control S 1 E ( dotted line), in contrast to malonic acid ( dashed lines), which
does not reduce the initial removal rate. This result is said to be
"surprising[]." (Id. at 11 [0034].)
In Example 4 (Spec 11-12 [0035]), the initial removal rate (at O days,
RR= 17.99 mg/min) obtained with malonic acid at pH 1.3 (adjusted with
nitric acid, HNQ3) is significantly higher than the initial RR of 10.9 mg/min
obtained with malonic acid at its natural pH 2.6 (i.e., pH not adjusted with
4
Appeal2018-001477
Application 14/094,921
nitric acid). (Id. at 12, Table 7.) At both lower and higher pH, the rates of
removal with malonic acid remain relatively high (RR= 17.55 mg/min
and 11.18 mg/min, respectively) after 166 hr. Citric acid, used as a
stabilizer, also shows an enhanced removal rate (17 .36 mg/min) at pH 1.3
(compared to RR= 13.37 mg/.ml at pH 2.7), but after 166 hours, the RR
falls to 15.95 mg/hr. Thus, malonic acid is said to be a more effective
catalyst stabilizing agent than citric acid, contrary to the results reported by
Ohashi. (Id. at 11 [0035], last sentence.)
Sole independent claim 1 is representative and reads:
A chemical mechanical polishing (CMP) method for planarizing
a nickel phosphorus (NiP) substrate, the method comprising
abrading a surface of the substrate with a CMP composition;
the CMP composition comprising
a particulate abrasive
suspended in an aqueous carrier
having a pH of less than 1.5, and containing
an oxidizing agent comprising hydrogen peroxide,
a metal ion catalyst capable of reversible oxidation
and reduction in the presence ofNiP and the oxidizer,
a catalyst stabilizing agent, and
a Ni complexing agent, wherein the Ni complexing
agent is glycine;
wherein the catalyst stabilizing agent is malonic acid,
and wherein the catalyst stabilizing agent is present
in the CMP composition at a concentration of
about 0.04 to about 0.2 wt% and
present in a molar concentration
of 2 to 5 times the metal ion molar concentration.
(Claims App., Br. 7; some formatting, and emphasis added.)
5
Appeal2018-001477
Application 14/094,921
The Examiner maintains the following ground of rejection: 6, 7
Claims 1-5, 7, 9-12, 16, and 17 stand rejected under 35 U.S.C.
§ 103 in view of the combined teachings of Chinnathambi 'O 16, 8
Chinnathambi '470, 9 Small, 10 and Streinz. 11
B. Discussion
The Board's findings of fact throughout this Opinion are supported by
a preponderance of the evidence of record.
We find that Zhang focuses arguments for patentability based on
limitations recited in claim 1. We likewise focus our attention on that claim.
Briefly, the Examiner finds (FR 2-3, ,r 6) that Chinnathambi '016
describes a CMP composition for NiP disks comprising particulate abrasives
in an aqueous carrier having "any suitable pH" paragraph [0023], and, in
paragraph [0021 ], glycine as a complexing agent for nickel. 12 The Examiner
6 Examiner's Answer mailed 22 September 2017 ("Ans.").
7 Because this application was filed after the 16 March 2013, effective date
of the America Invents Act, we refer to the AIA version of the statute.
8 Selvaraj Palanisamy Chinnathambi and Haresh Siriwardane, Polishing
composition for nickel-phosphorous memory disks, U.S. Patent Application
Publication 2010/0308016 Al (2010) (assigned to Cabot).
9 Selvaraj Palanisamy Chinnathambi and Haresh Siriwardane, Polishing
composition for nickel-phosphorous memory disks, U.S. Patent Application
Publication 2010/0193470 Al (2010) (assigned to Cabot).
10 Robert J. Small and Brandon S. Scott, Catalytic composition for chemical-
mechanical polishing, method of using same, and substrate treated with
same, U.S. Patent Application Publication 2004/0029495 Al (2004).
11 Christopher C. Streinz et al., Composition and method for polishing rigid
disks, U.S. Patent No. 6,015,506 (2000) (assigned to Cabot).
12 Chinnathambi 'O 16 describes complexing agents as materials that "affect
the dispersion of the particles in the polishing composition, and thus
6
Appeal2018-001477
Application 14/094,921
finds that Chinnathambi 'O 16 neither discloses the use of a metal ion catalyst
or a catalyst stabilizing agent (and the amounts required), nor that the pH is
desirably less than 2. (FR 3, ,r 7.) The Examiner finds that Streinz discloses
a CMP composition with a metal ion catalyst capable of reversible oxidation
and reduction, as recited in the claim, and concludes that it would have been
obvious to include the metal catalyst in the composition disclosed by
Chinnathambi 'O 16 for the disclosed purpose as an aid in polishing.
(Id. at ,r 9.) The Examiner finds (id. at 4, ,r 10) that Small discloses, in
paragraph [0038], CMP compositions comprising metal ion catalysts and
oxidizing agents, and that catalyst stabilizing agents, including malonic acid,
may be present at concentrations of about 0.001 to about 2 weight percent of
the composition, which encompass the range of about 0.04 to about 0.2 wt%
required by claim 1. The Examiner reasons that, because the general
conditions of the CMP process were known, it would have required no more
than routine experimentation to determine the optimum or workable
conditions, and concludes that the amounts of stabilizer would have been
obvious. (FR 4, ,r 10, citing In re Aller, 220 F.2d 454,456 (CCPA 1955).)
Finally, the Examiner finds that Chinnathambi '470 discloses CMP for NiP
influence the removal rate, microwaviness, and edge roll-off of a substrate
polished with the polishing composition." (Chinnathambi '016 [0021].)
Glycine, in particular, is thought to result in "improved microwaviness of the
disk." (Id.) (The term "microwaviness" refers to wavelengths of the
roughness of the surface of a disk that are on the order of the length of the
transducing [i.e., the writing or reading] head, said to be in the range of 10 to
5000 microns. (Id. at [0003].)) Zhang does not object to the Examiner's
characterization, which we do not find unreasonable, given that
the '921 Specification indicates that Ni ions are formed during the polishing
process, and glycine, if present, would have been expected to complex with
those ions, regardless of the reason Chinnathambi 'O 16 puts it into the slurry.
7
Appeal2018-001477
Application 14/094,921
disks using a particulate abrasive in an aqueous carrier having a pH in the
range of about 1 to about 5. (Id. at 5---6, ,r 12.) The Examiner concludes that
the encompassed range of pH less than 2, required by claim 1, would have
been obvious as a matter of routine experimentation based on a reasonable
expectation of success. (Id.)
Zhang argues that the Examiner erred harmfully because the prior art
relied on does not disclose the "general conditions for the present claims."
(Br. 5, 2d para.) More particularly, Zhang urges that Small discloses
catalysts that are coated on the abrasive particles, rather than in solution.
(Br. 3, last para.) This means, according to Zhang, that "the concentration
and ratio of the stabilization agent is not particularly important." (Id. at 4,
penultimate sentence.) Zhang argues further that Small's disclosure of a
general range relates to all possible additives, not just to catalyst stabilizing
agents. (Id. at 5, 2d para.) Moreover, in Zhang's view, Small does not
provide sufficient teachings to recognize the presence of stabilizer as a result
effective variable to guide optimization by routine experimentation. (Id.) In
this regard, Zhang observes that Small does not provide any examples of
CMP compositions comprising a stabilizing agent. (Id.)
Zhang urges that Chinnathambi '470 does not teach any pH effect on
the CMP process, and further that the '921 Specification shows that oxalic
acid and malonic acid have distinct behaviors with changing pH. (Id. at 3rd
para.) Moreover, Zhang urges that the teachings of Chinnathambi '470 are
limited to CMP compositions containing oxalic acid and optionally tartaric
acid as stabilizers, to obtain CMP compositions have lower chemical oxygen
8
Appeal2018-001477
Application 14/094,921
demand. 13 (Id. at 3, 3rd full para., and at 4, 3rd para.) Thus, in Zhang's
view, extending Chinnathambi '470's teachings regarding a pH range of
pH 1-5 to the hypothesized CMP said to be obvious in view of
Chinnathambi 'O 16, Streinz, and Small, is not supported reasonably by
evidence of record.
Zhang also criticizes the combination of the teachings of Small with
those of Chinnathambi 'O 16 as lacking motivation, given Small's interest in
high polishing rates (enhanced by the presence of the metal ion catalyst), and
Chinnathambi 'O 16' s primary interest in improved micro waviness, not
increased polishing rates. (Id. at 5, 4th para.)
Reviewing the record, we conclude that the Examiner has not
established a prima facie case of obviousness. The concerns of
Chinnathambi '016 with improved [i.e., diminished] microwaviness and of
Chinnathambi '470 with water purity make striking the absence of
recommendations that well-known metal ion catalysts be used in the
disclosed CMP compositions of these patents. Moreover, the focus of
Chinnathambi '470 on oxalic acid, or oxalic acid in combination with tartaric
acid, without more, limits the applicability of its teachings regarding pH
ranges of from 1 to 5. The Examiner has not directed our attention to
evidence in the present record that would have prompted an investigation of
the slurries having a pH below 2 in the CMP slurries of Chinnathambi 'O 16
modified to contain metal ion catalysts as taught by Streinz and by Small.
13 Chinnathambi '4 7 0 teaches that " [ o ]ne measure of water quality is known
as chemical oxygen demand ... a measure of the amount of oxygen required
to fully oxidize organic material in a waste stream to carbon dioxide,
ammonia, and water." (Chinnathambi '470 [0003].)
9
Appeal2018-001477
Application 14/094,921
Indeed, the express teachings of Small are limited to a pH range of 2 to 7.
The Examiner's determination that "such pH of about 2 is sufficiently close
to Appellant's pH of 1.5" (Ans. 4, 1. 3), is a finding of fact that lacks credible
supporting evidence in the record that a factor of about three 14 in hydrogen
ion concentration would have been regarded as "sufficiently close" in this art
to yield predictable results at pH values less than recommended by Small.
These concerns are intensified by the distinct character of the catalysts
described by Small, which are heterogeneous-present only on the surfaces
of the abrasive particles 15-rather than in solution, like the soluble ferric
nitrate salts exemplified by Streinz in Examples 3 and 4 (Streinz, cols. 11-
12.)
Finally, there appears to be no indication in the prior art that
markedly improved removal rates might be obtained in solutions having pH
less than 1.5 compared to non-adjusted pH values of about 2.6 (see Table 7,
Spec. 12). 16 Thus, there appears to be no basis to determine that the general
conditions of the reaction were sufficiently well-known, prior to Zhang's
14 pH is defined as the negative of the logarithm of the hydrogen ion
concentration: pH= -log[H+]. Thus, a difference of 0.5 pH units is a factor
of 10°·5 = v'lO :::::; 3.
15 We decline to credit Zhang's more specific arguments, mentioned supra
at 8, first full para., as Zhang has not supported these arguments with
citation to authority of record.
16 It has not escaped our notice that Small teaches that "the preferred [pH]
levels, are believed to facilitate control of the CMP process. A composition
having a pH that is too low, such as below pH 2, may present problems in
terms of the handling of the composition and the quality of the polishing
itself." (Small 4 [0033], emphasis added.)
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Appeal2018-001477
Application 14/094,921
work described in the '921 Specification, to allow a reasonable expectation
that the improved results would have been achieved or predicted.
Accordingly, we are persuaded of harmful error in the appealed
rejection, and we reverse.
C. Order
It is ORDERED that the rejection of claims 1-5, 7, 9-12, 16, and 17 is
reversed.
REVERSED
11