Ex parte Plumton

Board of Patent Appeals and Interferences

Sep 20, 1999

08158673 (B.P.A.I. Sep. 20, 1999)

Application for patent filed November 29, 1993. According to1
appellant, this application is a continuation-in-part of Application No.
08/056,682, filed April 30, 1993, now abandoned.
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today (1) was not
written for publication in a law journal and (2) is not binding
precedent of the Board.
Paper No. 12
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte DONALD L. PLUMTON
____________
Appeal No. 1996-1616
Application No. 08/158,6731
____________
ON BRIEF
____________
Before BARRETT, TORCZON, and GROSS, Administrative Patent
Judges.
GROSS, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the examiner's final
rejection of claims 1 through 9. Claims 10 through 16 have
been withdrawn from consideration.
The appellant's invention relates to an integrated
circuit having the same layer of semiconductor material
Appeal No. 1996-1616
Application No. 08/158,673
2
forming both the drain of a vertical field effect transistor
and also the cathode of a diode. Claim 1 is illustrative of
the claimed invention, and it reads as follows:
1. An integrated circuit, comprising:
(a) a vertical field effect transistor with a drain in a
first portion of a first layer of semiconductor material; and
(b) a diode with a cathode including a second portion of
said first layer and spaced from said first portion.
The prior art references of record relied upon by the
examiner in rejecting the appealed claims are:
Müller 4,183,036 Jan. 08,
1980
Yoshida et al. (Yoshida) 4,288,800 Sep.
08, 1981
Blanchard et al. (Blanchard) 4,896,196 Jan.
23, 1990
Korman et al. (Korman) 5,111,253 May 05,
1992
Lüth 5,122,853 Jun.
16, 1992
Claim 6 stands rejected under 35 U.S.C. § 112, second
paragraph, as being indefinite.
Claim 1 stands rejected under 35 U.S.C. § 102(b) as being
anticipated by Blanchard.
Claims 2 through 5, 7, and 8 stand rejected under 35
U.S.C. § 103 as being unpatentable over Blanchard in view of
Appeal No. 1996-1616
Application No. 08/158,673
For each ground of rejection which appellant contests and which2
applies to a group of two or more claims, the Board shall select a single
claim from the group and shall decide the appeal as to the ground of rejection
on the basis of that claim alone unless a statement is included that the
claims of the group do not stand or fall together and, in the argument under
paragraph (c)(8) of this section, appellant explains why the claims of the
group are believed to be separately patentable. Merely pointing out
differences in what the claims cover is not an argument as to why the claims
are separately patentable." 37 CFR § 1.192(c)(7) (underlining added for
3
Lüth, further in view of Müller (for claim 5), Korman (for
claim 7), or Yoshida (for claim 8).
Claim 9 stands rejected under 35 U.S.C. § 103 as being
unpatentable over Blanchard in view of Korman.
Reference is made to the Examiner's Answer (Paper No. 11,
mailed October 25, 1995) for the examiner's complete reasoning
in support of the rejections, and to the appellant's Brief
(Paper No. 10, filed October 3, 1995) for the appellant's
arguments thereagainst.
OPINION
As a preliminary matter, we note that appellant has
indicated on page 3 of the Brief that claims 1, 2 through 4,
5, 6, 7, 8, and 9 are not to stand or fall together. However,
for claims 2 through 4, 7, and 9 appellant has not presented
reasons as set forth in 37 CFR § 1.192(c)(7) as to why the2
Appeal No. 1996-1616
Application No. 08/158,673
emphasis)
4
claims are separately patentable. In fact, appellant has
pointed to the arguments for claim 1 for all of claims 2
through 4, 7, and 9. Accordingly, we will treat the claims as
falling into 4 groups as follows: (1) claims 1 through 4, 7,
and 9, (2) claim 5, (3) claim 6, and (4) claim 8, with claim 1
being representative of group 1.
We have carefully considered the claims, the applied
prior art references, and the respective positions articulated
by the appellant and the examiner. As a consequence of our
review, we will reverse the indefiniteness rejection of claim
6, affirm the anticipation rejection of claim 1 and the
obviousness rejections
of claims 2 through 4, 7, and 9, and reverse the obviousness
rejection of claims 5 and 8.
With respect to the rejection of claim 6 under 35 U.S.C.
§ 112, second paragraph, the examiner contends (Final
Rejection, page 1) that "it is not clear how the cathode can
include a portion of the source layer." The examiner asserts
Appeal No. 1996-1616
Application No. 08/158,673
5
that the cathode cannot be part of the source layer because
"figs. (14-16) of the application (and associated explanation)
clearly shows that the cathode can only be a part of the
drain, since the source layer is separated from the diode
cathode by the gate, channels and the isolation structure."
(Final Rejection, page 1.) The examiner apparently has
limited "source layer" to only the "source." However,
appellant discloses (Specification, page 17, second full
paragraph) that "the Schottky diode has n cathode 1454 of_
thickness equal to the sum of the thickness of drain layer
1408 plus the thickness of n source layer 1402," where_
"source layer" clearly refers to the entire epitaxial layer
which includes the source, the p region, and a portion of the+
cathode. Further, appellant (Specification, page 17, last
paragraph) explains the fabrication of the diode as including
"the n- GaAs channel/source epitaxial layer overgrowth, which
forms the upper portion of cathode 1454 of Schottky diode
1450." In addition, Figure 14 clearly shows layer 1402
forming the VFET channels in
between the gate fingers, the VFET source above the gate
fingers, and the upper portion of the diode cathode adjacent
Appeal No. 1996-1616
Application No. 08/158,673
6
to the gate fingers. Accordingly, the cathode does include a
portion of the source layer. Thus, we cannot sustain the
rejection of claim 6.
The examiner rejects claim 1 as being anticipated by
Blanchard. Claim 1 requires, in pertinent part, a vertical
field effect transistor. Appellant argues that Blanchard
includes a DMOS transistor and not a vertical field effect
transistor, because the arrows in Figure 3d show current flow
beginning in the horizontal direction. Blanchard defines the
vertical DMOS transistor devices of Figure 1 (column 1, lines
14-18) as "field effect transistor (FET) cell structures in
which a common substrate drain 10 serves multiple vertical
DMOS cells" (underlining added for emphasis). The transistor
in Figure 3d, upon which the examiner relies for the rejection
of claim 1, has the same structure as that of Figure 1. In
other words, Blanchard's transistor in Figure 3d has a
"vertical" structure and is a "field effect transistor" with a
substrate drain.
Although Blanchard's vertical cell differs from
appellant's vertical field effect transistor, appellant has
not clearly
Appeal No. 1996-1616
Application No. 08/158,673
7
defined the phrase in the specification. It is well
established
that "claims are not to be read in a vacuum, and limitations
therein are to be interpreted in light of the specification in
giving them their 'broadest reasonable interpretation.'" In
re Marosi, 710 F.2d 799, 218 U.S.P.Q. 289 (Fed.Cir. 1983).
Accordingly, "[w]ords which were defined in the specification
must be given the same meaning when used in a claim." McGill,
Inc. v. John Zink Co., 736 F.2d 666, 674, 221 U.S.P.Q. 944,
949 (Fed. Cir. 1984), cert. denied, 105 S.Ct. 514 (1984).
Conversely, where words or phrases are not clearly defined in
the specification, as in the present application, they must be
given the broadest reasonable interpretation. Giving the
phrase "vertical field effect transistor" its broadest
reasonable interpretation, we find that Blanchard's field
effect transistor which is described as being vertical
satisfies the phrase. As appellant has presented no further
arguments with respect to claim 1, we will sustain the
rejection of claim 1. Further since claims 2 through 4, 7,
Appeal No. 1996-1616
Application No. 08/158,673
8
and 9 stand or fall with claim 1, we also will affirm the
obviousness rejection of those claims.
As to claim 5, Blanchard's body region 63 could be viewed
as isolating the transistor from the diode. Blanchard,
however,
does not disclose a trench to separate the two elements. The
examiner turns to Müller to substitute a trench structure for
Blanchard's isolation element. The examiner states (Final
Rejection, page 4) that "the prior art teaches that a trench
structure can be used to isolate elements which inturn [sic]
decreases noise interference between integrated circuits on
the same substrate." We find no teaching or suggestion in
Müller, and the examiner fails to point to any particular
portion, which would motivate one of ordinary skill in the art
to use a trench in Blanchard's device. Merely that the prior
art can be modified in the manner suggested by the examiner
does not make the modification obvious unless the prior art
suggested the desirability of the modification. In re Fritch,
972 F.2d 1260, 1266, 23 USPQ2d 1780, 1783-4 (Fed. Cir. 1992).
"There must be some reason, suggestion, or motivation found in
Appeal No. 1996-1616
Application No. 08/158,673
9
the prior art whereby a person of ordinary skill in the field
of the invention would make the combination." In re Oetiker,
977 F.2d 1443, 1447, 24 USPQ2d 1443, 1446 (Fed. Cir. 1992).
Accordingly, we cannot sustain the rejection of claim 5.
For claim 8, the examiner combines Yoshida with Blanchard
and Luth. As pointed out by appellant (Brief, page 4)
"Yoshida has no suggestion of diodes and thus [no] suggestion
of the
requirement [of] a common doping profile of claim 8." The
examiner contends (Answer, page 5) that "the Yoshida reference
was not used to show the doping profile, but was used to show
the claimed gate structure." The examiner continues (Answer,
page 6) that "[i]t is also clear from the Blanchard reference
both regions 63d and 63 have a P concentration and not just+
one region having a P or a P (which is a common notation to- ++
show different concentration levels of semiconductor regions)
relative to the other region." However, since the device of
Blanchard must be modified to incorporate the gate structure
of Yoshida, the entire transistor structure gets changed.
Thus, even if Blanchard has common doping profiles before the
Appeal No. 1996-1616
Application No. 08/158,673
10
modification, it is unclear to us how Blanchard can continue
to disclose common doping profiles after the modification if
the whole transistor is different. Accordingly, we will not
sustain the rejection of claim 8.
CONCLUSION
In summary, the decision of the examiner rejecting claim
6 under 35 U.S.C. § 112, second paragraph is reversed. The
decision of the examiner rejecting claim 1 under 35 U.S.C.
§ 102(b) and claims 2 through 4, 7, and 9 under 35 U.S.C. §
103 is affirmed. The decision of the examiner rejecting
claims 5 and 8 under 35 U.S.C. § 103 is reversed.
The examiner's decision is affirmed-in-part.
Appeal No. 1996-1616
Application No. 08/158,673
11
No time period for taking any subsequent action in
connection with this appeal may be extended under 37 CFR
§ 1.136(a).
AFFIRMED-IN-PART
LEE E. BARRETT )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
RICHARD TORCZON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
ANITA PELLMAN GROSS )
Administrative Patent Judge )
vsh
Appeal No. 1996-1616
Application No. 08/158,673
12
CARLTON H. HOEL
TEXAS INSTRUMENTS PATENT DEPT.
MAIL STATION 219
P. O. BOX 655474
DALLAS, TX 75265