Ex Parte Kawasaki

Board of Patent Appeals and Interferences

May 30, 2007

10470060 (B.P.A.I. May. 30, 2007)

The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte MASAHIRO KAWASAKI
____________

Appeal 2007-0442
Application 10/470,060
Technology Center 1700
____________

Decided: May 30, 2007
____________

Before CHUNG K. PAK, THOMAS A. WALTZ, and JEFFREY T. SMITH,
Administrative Patent Judges.

PAK, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal from the Examiner's final rejection of claims 3, 5, 6,
and 7, all of the claims pending in the above-identified application. We have
jurisdiction pursuant to 35 U.S.C. §§ 6 and 134.

Appeal 2007-0442
Application 10/470,060

The subject matter on appeal is directed to “a method of forming a
thick silicon dioxide film on a silicon substrate” (Specification 1). The
method “comprises repeating steps of depositing a silicon layer on a silicon
substrate and then, subjecting the silicon layer to a thermal oxidation
treatment to form a silicon dioxide film of a predetermined thickness….”
(Specification 3). This method is said to overcome the problems associated
with a typical thick silicon dioxide film forming method (Specification 1-2).
Details of the appealed subject matter are recited in representative claim 3
reproduced below:
3. A method of forming a silicon dioxide film of a predetermined
thickness on a silicon substrate, comprising:

a deposition step of depositing epitaxial silicon on said silicon
substrate or on a silicon dioxide film formed on said silicon substrate by a
thermal oxidation treatment to obtain a deposited epitaxial silicon film; and

a thermal oxidation step of oxidizing said deposited epitaxial
silicon film by heat to convert it into a silicon dioxide film,

wherein said deposition step and said thermal oxidation step are
repeated a plural number of times.

As evidence of unpatentability of the claimed subject matter, the
Examiner has relied upon the following references:
Jacobson US 3,807,039 Apr. 30, 1974
Faraone US 4,604,304 Aug. 5, 1986
Corboy, Jr. US 4,698,316 Oct. 6, 1987
Arai US 2001/0001384 A1 May 24, 2001
Sato US 6,375,738 B1 Apr. 23, 2002
2
Appeal 2007-0442
Application 10/470,060

The Examiner has rejected the claims on appeal as follows:
1) Claims 3 and 5 under 35 U.S.C. § 103(a) as unpatentable over
the combined teachings of Faraone and Jacobson; and
2) Claims 6 and 7 under 35 U.S.C. § 103(a) as unpatentable over
the combined teachings of Faraone, Jacobson, Corboy, Jr., Sato, and Arai.
In support of his rejection of the claims on appeal1, the Examiner has
found (Answer 3-4) that Faraone, like the Appellant, broadly teaches:

[A] process of producing thick layers of silicon dioxide on a
silicon substrate by initially oxidizing the substrate to form a
thin layer of silicon dioxide thereon, subsequently depositing a
thin layer of silicon and oxidizing this thin silicon layer to
increase the size of the silicon dioxide layer (Summary of
Invention). To form a desired thickness of silicon dioxide the
deposition steps and oxidation steps are repeated as necessary
(Claim 1, column 4; Summary of Invention, column 2). Faraone
discloses the thickness of silicon per one deposition between
120 and 400 nanometers (Column 3, lines 6-8).

Recognizing that Faraone does not specifically mention the claimed
epitaxial silicon layer, the Examiner has relied on Jacobson to explain that
Falaone’s silicon layer includes the claimed epitaxial silicon layer (Answer
4). Specifically, the Examiner has found that consistent with Faraone’s
disclosure above, Jacobson teaches that deposition and thermal oxidation of
a thin epitaxial silicon layer on a silicon substrate is useful for forming an
insulating silicon dioxide coating (id).

1 According to the Appellant (Br. 5), “claims 3, 5, 6, and 7 stand or fall
together.”
3
Appeal 2007-0442
Application 10/470,060

Relying on the above teachings, the Examiner has determined that one
of ordinary skill in the art would have been led to deposit and thermally
oxidize thin silicon layers, including epitaxial silicon layers, in Faraone’s
method, with a reasonable expectation of successfully forming an insulating
silicon dioxide film having a desired thickness (id). According to the
Examiner (id):
Faraone teaches thermally oxidizing a silicon [layer inclusive of
the epitaxial silicon taught by Jacobson] to provide a[n]
insulating silicon dioxide film and Jacobson teaches that it is
known in the art that a known method of producing a silicon
dioxide film is thermally oxidizing an epitaxial silicon layer.

The Appellant contends that Faraone and Jacobson do not provide any
suggestion to employ the epitaxial silicon layer in Faraone’s method (Br.
8-11). The Appellant also indicates that “the use of epitaxial silicon yields
several advantages as demonstrated in Figure 2 of Appellant’s invention”
(Br. 7).
The dispositive question is whether one of ordinary skill in the art
would have been led to deposit and thermally oxidize thin silicon layers,
such as thin epitaxial silicon layers, in the process of Faraone, with a
reasonable expectation of successfully obtaining an insulating silicon
dioxide layer or film having a desired thickness within the meaning of
35 U.S.C. § 103. On this record, we answer this question in the affirmative.
Although Faraone exemplifies depositing and thermally oxidizing
amorphous silicon layers on a substrate as argued by the Appellant, it clearly
is not limited to such an embodiment. See also In re Boe, 355 F.2d 961,
965, 148 USPQ 507, 510 (CCPA 1966) (all of the disclosures in a reference,
4
Appeal 2007-0442
Application 10/470,060

including non-preferred embodiments, “must be evaluated for what they
fairly teach one of ordinary skill in the art”); Merck & Biocraft Labs., Inc.,
874 F.2d 804, 807, 10 USPQ2d 1843, 1846 (Fed. Cir. 1989)(“the fact that a
specific [embodiment] is taught to be preferred is not controlling, since all
disclosures of the prior art, including unpreferred embodiments, must be
considered”). As indicated supra, Faraone teaches employing any thin layer
of silicon susceptible to forming a silicon dioxide layer via thermal
oxidation. Faraone as a whole, like the Appellant, focuses on repeating
deposition and thermal oxidation of thin silicon layers to incrementally form
a desired thick silicon dioxide film to avoid any disadvantages associated
with conventional thick silicon dioxide film forming processes (Faraone,
Abstract and col. 1 to col. 4). Jacobson explains that, inter alia, thin
epitaxial silicon layers, like other deposited silicon layers, are well known to
be capable of being converted to silicon dioxide films upon being subjected
to thermal oxidation.
Thus, given the recognized need to form a thick silicon dioxide film
on a substrate (Faraone, col. 1, ll.9-20), we concur with the Examiner that
one of ordinary skill in the art would have been led to deposit and thermally
oxidize thin silicon layers, such as amorphous and epitaxial silicon layers, in
Faraone’s thick silicon dioxide film forming process, with a reasonable
expectation of successfully forming a desired thick silicon dioxide film. See
also KSR Int’l Co. v. Teleflex, Inc., 127 S. Ct. 1727, 1739, 82 USPQ2d 1385,
1395 (2007)(“The combination of familiar elements according to known
methods is likely to be obvious when it does no more than yield predictable
results.”); In re Hoeschele, 406 F.2d 1403, 1406-07, 160 USPQ 809, 811-
5
Appeal 2007-0442
Application 10/470,060

812 (CCPA 1969) (“[I]t is proper to take into account not only specific
teachings of the references but also the inferences which one skilled in the
art would reasonably be expected to draw therefrom...”).
The Appellant asserts that “the use of epitaxial silicon yields several
advantages as demonstrated in Figure 2 of Appellant’s invention” (Br. 7).
However, the Appellant does not aver, much less argue, that these
advantages are unexpected. In re Klosak, 455 F.2d 1077, 1080, 173 USPQ
14, 16 (CCPA 1972) (the difference in the results obtained by the claimed
subject matter and the prior art must be shown to be unexpected); In re
Geisler, 116 F.3d 1465, 1469-70, 43 USPQ2d 1362, 1365 (Fed. Cir.
1997)(party asserting unexpected results has the burden of proving that the
results are unexpected). Nor does the Appellant explain why the showing
relied upon is reasonably commensurate in scope with the breadth of the
claimed invention. In re Harris, 409 F.3d 1339, 1344, 74 USPQ2d 1951,
1955 (Fed. Cir. 2005); In re Greenfield, 571 F.2d 1185, 1189, 197 USPQ
227, 230 (CCPA 1978). The Appellant simply fails to prove that the
claimed invention imparts unexpected results, thereby failing to rebut any
inference of obviousness established by the Examiner. See, e.g., In re
Heyna, 360 F.2d 222, 228, 149 USPQ 692, 697 (CCPA 1966)(applicant
required to submit clear and convincing evidence to support an allegation of
unexpected property).
As to the § 103 rejection of claims 6 and 7, the Appellant only argues
that none of Corboy Jr., Sato, and Aria remedies the above-argued
deficiencies in Faraone and Jacobson. Thus, for the same reasons set forth
above, we determine that the Appellants’ argument is not convincing.
6
Appeal 2007-0442
Application 10/470,060

In view of the forgoing, we determine that the prior art relied upon by
the Examiner would have rendered the claimed subject matter obvious to
one of ordinary skill in the art within the meaning of 35 U.S.C. § 103.
Accordingly, the decision of the Examiner 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

cam

SMITH GAMBRELL & RUSSELL
Suite 800 1850 M Street, N.W.
Washington, DC 20036
7