Ex Parte Pflugler et al

Board of Patent Appeals and Interferences

Feb 15, 2011

11096605 (B.P.A.I. Feb. 15, 2011)

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.
11/096,605 04/01/2005 Bernhard Pflugler WAS 0688 PUS 7487
22045 7590 02/15/2011
BROOKS KUSHMAN P.C.
1000 TOWN CENTER
TWENTY-SECOND FLOOR
SOUTHFIELD, MI 48075
EXAMINER
NGUYEN, NGOC YEN M
ART UNIT PAPER NUMBER
1734
MAIL DATE DELIVERY MODE
02/15/2011 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
________________

Ex parte BERNHARD PFLUGLER,
GERHARD TRAUNSPURGER, and
WALTER GRUNLEITNER
________________

Appeal 2010-001008
Application 11/096,605
Technology Center 1700
________________

Before BRADLEY R. GARRIS, ADRIENE LEPIANE HANLON, and
PETER F. KRATZ, Administrative Patent Judges.

GARRIS, Administrative Patent Judge.

DECISION ON APPEAL1

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or for filing a request for rehearing,
as recited in 37 C.F.R. § 41.52, begins to run from the "MAIL DATE"
(paper delivery mode) or the "NOTIFICATION DATE" (electronic delivery
mode) shown on the PTOL-90A cover letter attached to this decision.
Appeal 2010-001008
Application 11/096,605

2
Appellants appeal under 35 U.S.C. § 134 from the Examiner's
decision rejecting claims 2-4, 9, 11-18, 23, and 25-282. We have jurisdiction
under 35 U.S.C. § 6.
We REVERSE.
Appellants claim a process for preparing trichlorosilane comprising
reacting silicon dust particles with hydrogen chloride in a fluidized bed
reactor, the silicon dust consisting essentially of silicon dust having a
specified particle size distribution and obtained from (e.g., by crushing)
metallurgical grade lump-form silicon (independent claims 14, 25), "wherein
the trichlorosilane is suitable for the preparation of ultrapure silicon in the
semiconductor and photovoltaic industries" (claim 25).
Representative claim 25 reads as follows:
25. A process for the commercial preparation of
trichlorosilane comprising reacting silicon dust particles with
hydrogen chloride in a fluidized bed reactor, the silicon dust
consisting essentially of metallurgical grade silicon dust, said
silicone dust directly obtained as a waste product in the
preparation of defined silicon particle size fractions from
metallurgical grade lump-form silicon, the silicon dust having a
silicon dust particle size distribution within the bounds of Type
1 and Type 4 silicon dusts of Figure 1, and separating
trichloromonosilane from a product gas stream, wherein the

2 According to the Examiner, "[c]laims 10, 19, 21-22 have been canceled
because they were withdrawn from this appeal by Appellants (note Office
action mailed May 22/2009)" (Ans. 3), and Appellants do not argue
otherwise. As a consequence, claims 23 and 27 depend from now-canceled
claim 21. For purposes of resolving this appeal, we will treat claims 23 and
27 as though they depend directly from their ultimate parent claim which is
claim 25. However, in any further prosecution that may occur, the
dependency problem of claims 23 and 27 should be corrected.
Appeal 2010-001008
Application 11/096,605

3
trichlorosilane is suitable for the preparation of ultrapure silicon
in the semiconductor and photovoltaic industries.
The Examiner rejects claims 2-4, 9, 11-13, 23, 25-28 under the 1st
paragraph of 35 U.S.C. § 112 as failing to comply with the written
description requirement.
The Examiner rejects all appealed claims under 35 U.S.C. § 103(a) as
unpatentable over Straussberger (US 4,224,297 issued Sept. 23, 1980),
optionally further in view of Kalchauer (US 2002/0151737 A1 published
Oct. 17, 2002).3

The § 112, 1st paragraph, Rejection

The Examiner regards a certain recitation of independent claim 25 as
violating the written description requirement. Specifically, the Examiner
states that "[t]here is no sufficient support for the limitation 'the
trichlorosilane is suitable for the preparation of ultrapure silicon in the
semiconductor and photovoltaic industries' as now required in the instant
claim 25 if the limitation 'suitable for' intends to exclude any extra
purification step" (Ans. 5).
Appellants argue that trichlorosilane from a direct synthesis process
"is easily purified to produce ultrapure trichlorosilane" suitable for the use
recited in claim 25, that "[a]ll the [Specification] examples employ just such
a process", and that "one skilled in the art immediately recognizes that the

3 In light of our disposition of this appeal, a discussion of Kalchauer is
unnecessary particularly since this reference has not been relied upon by the
Examiner to supply the deficiencies of Straussberger which are highlighted
in this opinion.
Appeal 2010-001008
Application 11/096,605

4
trichlorosilane isolated from the product stream of these examples is suitable
for preparing ultrapure silicon" (App. Br. para. bridging 6-7). It is
Appellants' position that one with ordinary skill in this art would understand
from reading their Specification that "Appellants had the concept of
preparing ultrapure trichlorosilane suitable for use in the semiconductor and
photovoltaic industries at the time of filing the application" (id. at para.
bridging 7-8).

Appellants' argument is persuasive.
As indicated above, this rejection is premised on the Examiner's
assumption that claim 25 "intends to exclude any extra purification step"
(Ans. 5). Neither claim 25 nor the Specification disclosure supports this
assumption. Moreover, the Examiner's assumption is undermined by
Appellants' above-noted argument indicating that trichlorosilane from the
claim 25 process would be "easily purified to produce ultrapure
trichlorosilane" (App. Br. para. bridging 6-7). Under these circumstances,
the Examiner has failed to carry the burden of establishing that claim 25 and
the claims which depend therefrom violate the written description
requirement.
Therefore, we will not sustain the Examiner's § 112, 1st paragraph,
rejection of claims 2-4, 9, 11-13, 23, and 25-28.

The § 103 Rejection

It is undisputed that Straussberger discloses a process for preparing
trichlorosilane by reacting hydrogen chloride with a mixture of treated
Appeal 2010-001008
Application 11/096,605

5
silicon residue and fine particles of silicon dust waste which are generated as
a byproduct in the grinding process for preparing granular silicon.
According to the Examiner, Straussberger's mixture of treated silicon
residue and silicon dust waste satisfies the independent claim requirement
for silicon dust (Ans. para. bridging 6-7). The Examiner explains that
Straussberger's silicon dust waste corresponds to Appellants' claimed silicon
dust and that Straussberger's treated silicon residue is encompassed by the
independent claim term "comprising" and therefore is not excluded by the
independent claim phrase "consisting essentially of" (id.). Alternatively
(i.e., assuming the independent claim phrase "consisting essentially of"
excludes Straussberger's treated silicon residue), the Examiner concludes
that it would have been obvious to eliminate the treated silicon residue from
the process of Straussberger (id.).
Concerning Appellants' claimed silicon dust particle size distribution,
the Examiner states: "Straussberger does not specifically disclose the
particle size distribution, however, it would have been obvious to one of
ordinary skill in the art to optimize the particle size distribution for the
silicon source (either or both the treated residue or the silicon dust waste) in
Straussberger . . . to obtain the best results when the silicon source is used
for produc[ing] trichlorosilane" (Ans. para. bridging 7-8; see also id. at 15).
Appellants argue that Straussberger's treated silicon residue is
excluded by the claim phrase "consisting essentially of" and that, contrary to
the Examiner's conclusion, Straussberger contains no teaching or suggestion
of eliminating this treated residue (App. Br. 17-18; Reply Br. 2). Appellants
rely upon the Pflugler Declaration of record as support for this argument.

Appeal 2010-001008
Application 11/096,605

6
Appellants' argument has merit.
In the record before us, the Examiner has provided no convincing
rationale for the proposition that it is reasonable and consistent with
Appellants' Specification to interpret claims 14 and 25 as encompassing the
treated silicon residue of Straussberger simply because the claims contain
the term "comprising." As indicated by Appellants, this interpretation
appears to be contrary to the exclusionary consequence of the "consisting
essentially of" language of the independent claims (Reply Br. 2). Similarly,
the Examiner has provided this record with no evidentiary support for the
conclusion that it would have been obvious to eliminate the treated silicon
residue from Straussberger's process.
Even disregarding the above infirmity of the Examiner's position, the
§ 103 rejection still would be improper. As correctly argued by Appellants,
Straussberger contains no teaching or suggestion of the silicon dust particle
size distribution required by the independent claims and, more particularly,
contains no teaching or suggestion that silicon dust particle size distribution
is recognized in this art as a result-effective variable (App. Br. 16-17; Reply
Br. 3-4). For this reason, no proper basis exists for the Examiner's
conclusion that it would have been obvious to optimize the particle size
distribution of the silicon used in Straussberger's process.
For the above stated reasons, we will not sustain the Examiner's § 103
rejection of all appealed claims as unpatentable over Straussberger,
optionally in view of Kalchauer.

Conclusion
The decision of the Examiner is reversed.
Appeal 2010-001008
Application 11/096,605

7

REVERSED
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BROOKS KUSHMAN P.C.
1000 TOWN CENTER
TWENTY-SECOND FLOOR
SOUTHFIELD, MI 48075