Ex Parte Ping et al

Board of Patent Appeals and Interferences

Mar 30, 2009

10379494 (B.P.A.I. Mar. 30, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ER-XUAN PING and JEFFREY A. MCKEE
_____________

Appeal 2009-0237
Application 10/379,494
Technology Center 2800
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Decided:1 March 30, 2009
____________

Before KENNETH W. HAIRSTON, JOSEPH F. RUGGIERO,
and ELENI MANTIS MERCADER, Administrative Patent Judges.

MANTIS MERCADER, Administrative Patent Judge.

DECISION ON APPEAL

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, begins to run from the decided date
shown on this page of the decision. The time period does not run from the
Mail Date (paper delivery) or Notification Date (electronic delivery).

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Application 10/379,494

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STATEMENT OF THE CASE
Appellants seek our review under 35 U.S.C. § 134 of the Examiner’s
final rejection of claims 117-119, 121-135, 144, 145, 148-162, 189, and 190.
We have jurisdiction under 35 U.S.C. § 6(b).
We affirm-in-part.

INVENTION
Appellants’ claimed invention is directed to using selective epitaxial
growth (SEG) to form vertically oriented structures on semiconductor
substrates (Spec. 2:5-6). As shown in Figure 3C, a first epitaxial layer is
grown on the exposed substrate surface 14” by SEG using the oxide layer
28” as a mask and additional epitaxial layers are then successively grown on
the preceding epitaxial layer to form the gate region 18” having a desired
length (Spec. 14:19-23). The source region 30’” is formed above the gate
18” by growing one or more layers of epitaxial silicon above the uppermost
epitaxial layer of the gate structure 18” (Spec. 14:24-25).
Claim 117, reproduced below, is representative of the subject matter
on appeal:
117. A transistor in a semiconductor device, comprising:
a substrate comprising a buried drain region;
a gate overlying the buried drain region and extending in a
vertical orientation from the substrate, the gate comprising multiple
overlying faceted layers of single crystal epitaxial silicon, including
an uppermost layer; each layer having sidewalls and a surface
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comprising a plurality of facets, the sidewalls having an insulative
layer thereon; and
a source region overlying the uppermost layer of the gate, the
source region comprising a faceted layer of single crystal epitaxial
silicon having a surface comprising a plurality of facets, the source
region being doped with a conductivity enhancing dopant, and
covered by a layer of insulative material.

THE REJECTIONS
The Examiner relies upon the following as evidence of
unpatentability:
Sharma US 5,483,094 Jan. 9, 1996

Matsumoto JP401286361 A Nov. 17, 1989
Stanley Wolf and Richard N. Tauber, Silicon Processing for the VLSI
ERA, Vol. 1: Process Technology, 1986, pp.155-56 (hereinafter Wolf).
The following rejections are before us for review:
1. The Examiner rejected claims 189 and 190 under 35 U.S.C. §
102(b) as being anticipated by Matsumoto.
2. The Examiner rejected claims 117-119, 121-135, 144, 145, and
148-162 under 35 U.S.C. § 103(a) as unpatentable over Sharma in view of
Wolf.
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Appellants argue the rejection of claims 189 and 190 as a group;
accordingly, we select claim 189 as representative (App. Br. 10-11).2 Thus,
claim 190 stands or falls with claim 189. See 37 C.F.R. § 41.37 (c)(1)(vii)
(2004). Appellants argue the rejection of claims 117-119, 121-135, 144,
145, and 148-162 as a group (App. Br. 12-16). Thus, claims 118-119, 121-
135, 144, 145, and 148-162 stand or fall with claim 117.
We note that Appellants do not set forth any substantive arguments of
patentability regarding claims 134-135, but only question whether those
claims were rejected by the Examiner (App. Br. 16). The Examiner
responded that the claims were rejected under 35 U.S.C. § 103(a) as obvious
over Sharma in view of Wolf (Ans. 11), and the Appellants did not further
address this issue in their Reply Brief. We have confirmed that the
Examiner did reject those claims and the relevant paragraph duplicated from
the Final Rejection section can be found on page 8 of the Answer.
We further note that Appellants’ argument, on page 16 of the Appeal
Brief, is directed to the Examiner’s requirement for Election/Restriction.
This is a petitionable matter and not an appealable matter. See Manual of
Patent Examining Procedure (MPEP) § 1002 and 1201. Accordingly, we
will not review that issue.

2 Only arguments made by Appellants have been considered in this decision.
Arguments which Appellants could have made but did not make in the Brief
have not been considered and are deemed waived. See 37 C.F.R. §
41.37(c)(1)(vii) (2004).
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ANTICIPATION
ISSUE
Appellants contend that Matsumoto’s Abstract clearly describes a
single layer SEG as layer 4 in Figure 3(b) (and in Fig. 1) (App. Br. 11).
Appellants further contend that the Abstract also states that if boron is
implanted into layer 4—a doped uniform base 6 is formed to the depth
shown in Figure 3(b) (and Fig. 1) (App. Br. 11). Thus, Appellants assert that
region 6 is not a second SEG layer, but, rather, a portion of SEG layer 4 that
is formed by doping (App. Br. 11). Furthermore, Appellants state that the
“line” within the SEG layer indicates the “depth” of the impurity that is
introduced into layer 4 to form the boron-doped region 6 (App. Br. 11).
Appellants further assert that the claimed term “epitaxial” layer means a
single crystal film grown upon a single crystal substrate in the course of
epitaxial deposition, and that the presence of an upper dopant region in an
epitaxial layer does not create two epitaxial layers (Reply Br. 2).
The Examiner responds that the depth region 6 constitutes a
distinguishable junction between the doped SEG layer and the undoped SEG
layer as indicated by the separating line in Figure 3(b), creating layers 4 and
6 (Ans. 9). Furthermore, the Examiner states that the term “layer,” “is a
single thickness of something that lies over or under something” (Ans. 10).
The issue before us, then, is as follows:
Have Appellants shown that the Examiner erred by determining that
Matsumoto teaches “overlying layers of epitaxial silicon” as recited in claim
189?
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FINDINGS OF FACT
The relevant facts include the following:
1. Matsumoto teaches forming an SEG layer region 4 wherein “an
impurity introduced layer” 6 is formed uniformly to the depth
direction “inside the selective epitaxial layer” 4 (Abstract and Fig.
3(b)).
2. Matsumoto’s Figure 3(b) shows that each of the silicon layers 4 and 6
has an upper surface with a plurality of facets.

PRINCIPLES OF LAW
“A claim is anticipated only if each and every element as set forth in
the claim is found, either expressly or inherently described, in a single prior
art reference.” Verdegaal Bros. Inc., v. Union Oil Co. of Cal., 814 F.2d 628,
631 (Fed. Cir. 1987).

ANALYSIS
Matsumoto teaches forming an SEG layer region 4 wherein “an
impurity introduced layer” 6 is formed uniformly to the depth direction
“inside the selective epitaxial layer” 4 (Abstract and Fig. 3(b)) (emphasis
added). Thus, layer 6 is an additional “doped” layer as it is characterized as
“an impurity introduced layer.” This introduced layer 6 was formed
originally as the upper region of SEG epitaxial layer 4, thereby constituting a
“doped” SEG layer 6. We note that Appellants’ definition of an “epitaxial”
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layer, meaning a single crystal film grown upon a single crystal substrate in
the course of epitaxial deposition, does not contradict the Examiner’s
interpretation because layer 6 was originally grown (i.e., as the top part of
SEG layer 4) upon a single crystal substrate, and thereafter treated with
boron so as to become a “doped” SEG layer 6. In passing, we note that
Figure 3(b) shows that each of the silicon layers 4 and 6 has an upper surface
with a plurality of facets, and thus, meets the claim limitation of “overlying
layers of epitaxial silicon, each of said silicon layers having . . . an upper
surface comprising a plurality of facets.”
For the foregoing reasons, Appellants have not persuaded us that the
Examiner erred in rejecting representative claim 189 or claim 190 which
falls with claim 189. Accordingly, we sustain the Examiner’s rejection of
claims 189 and 190.

CONCLUSION
Under 35 U.S.C. § 102(b), Appellants have not shown that the
Examiner erred by determining that Matsumoto teaches “overlying layers of
epitaxial silicon” as recited in claim 189 and dependent claim 190.

OBVIOUSNESS
ISSUE
Appellants do not contest that Wolf discloses that an epitaxial silicon
layer grown within an opening of SiO2 layer, as performed by Sharma, will
be angled at the interface with the SiO2 layer (App. Br. 14). Appellants
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contend, however, that Sharma does not describe growing separate layers of
epitaxial silicon, but rather, differently doped regions within an epitaxially
grown silicon pillar 31 (App. Br. 14).
The Examiner responds that multiple facets are inherent in the SEG
process as disclosed by Wolf in Figure 28, and the layers 32, 33, and 34 are
produced by the same process, i.e., SEG; thus they inherently have multiple
facets.
The second issue before us, then, is as follows:
Have Appellants shown that the Examiner erred by determining that
the combination of Sharma and Wolf teaches “multiple overlying faceted
layers . . . each layer having sidewalls and a surface comprising a plurality
of facets” as recited in representative claim 117?

FINDINGS OF FACT
The relevant facts include the following:
1. Sharma’s layers 32, 33, and 34 were originally created by silicon
epitaxial growth (SEG) of the silicon pillar 31 (Figs. 3 and 4; and col.
3, ll. 41-43) and formed into separate layers by doping (col. 3, ll. 44-
49).
2. The three silicon layers 32, 33, and 34 were not each separately
formed by the SEG process, but rather, they were collectively formed
through a single SEG process creating pillar 31.
3. Wolf teaches that selective epitaxial silicon deposition creates facets
on the top surface (Figure 28 (a) and (b)).
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PRINCIPLES OF LAW
The Examiner bears the initial burden of presenting a prima facie case
of obviousness. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992). If that
burden is met, then the burden shifts to the Appellants to overcome the
prima facie case with argument and/or evidence. Id. The Supreme Court,
citing In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006), stated that
“‘[[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.’” KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 127 S. Ct. 1727,
1741 (2007).

ANALYSIS
First we note that Sharma’s layers 32, 33, and 34 under the broadest
reasonable interpretation constitute multiple silicon SEG layers which were
originally created by silicon epitaxial growth (SEG) of the silicon pillar 31
and formed into separate layers by doping (Finding of Fact 1). This is the
same reasoning we used for our analysis supra. However, the three layers
32, 33, and 34 were not each separately formed by the SEG process, but
rather, they were collectively formed through a single SEG process creating
pillar 31 (Finding of Fact 2). Wolf teaches that selective epitaxial silicon
deposition creates facets on the top surface (Finding of Fact 3). Thus, the
selective epitaxial silicon deposition would create facets on the top surface
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of pillar 31—layer 34. However, layers 32, 33, and 34 were formed with
doping after the SEG deposition of pillar 31 of Sharma, and thus, the inner
layers 32 and 33 would not have facets. Accordingly, the multiple overlying
silicon layers would not each have a plurality of facets as required by claim
117, independent claims 128-132, 144-145, 148-150, 156, and 161 reciting
commensurate limitations, and dependent claims 118-119, 121-127, 133-
135, 151-155, 157-160, and 162. Thus, the Examiner’s assertion that the
SEG process would necessarily create facets in layers 32, 33, and 34 does
not constitute a rational underpinning to support the legal conclusion of
obviousness. KSR, 127 S. Ct. at 1741.
For the foregoing reasons, Appellants have persuaded us that the
Examiner erred in rejecting claims 117-119, 121-135, 144, 145, and 148-
162. Accordingly, we reverse the Examiner’s rejection of these claims.

CONCLUSION
Under 35 U.S.C. § 103(a), Appellants have shown that the Examiner
erred by determining that the combination of Sharma and Wolf teaches
“multiple overlying faceted layers . . . each layer having sidewalls and a
surface comprising a plurality of facets” or commensurate limitations recited
in claims 117-119, 121-135, 144, 145, and 148-162.

ORDER
The decision of the Examiner to reject claims 189 and 190
under 35 U.S.C. § 102(b) is affirmed and the decision of the Examiner
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to reject claims 117-119, 121-135, 144, 145, and 148-162 under 35
U.S.C. § 103(a) is reversed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED-IN-PART

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WHYTE HIRSCHBOECK DUDEK S.C.
INTELLECTUAL PROPERTY DEPARTMENT
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