Ex Parte Tsau

Patent Trial and Appeal Board

Dec 18, 2014

11505039 (P.T.A.B. Dec. 18, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
_________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte LIMING TSAU
__________

Appeal 2012-007526
Application 11/505,039
Technology Center 2800
___________

Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
JAMES C. HOUSEL, Administrative Patent Judges.

HANLON, Administrative Patent Judge.

DECISION ON APPEAL

A. STATEMENT OF THE CASE
The Appellant filed an appeal under 35 U.S.C. § 134 from a final rejection
of claims 1–20. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
On appeal, the Appellant’s arguments focus on claim 1 which is reproduced
below from the Claims Appendix of the Appeal Brief dated November 2, 2011
(“App. Br.”). The limitations at issue are italicized.
Claim 1: A transistor comprising:
a semiconductor substrate of a first conductivity type having
formed therein a well of a second conductivity type;
Appeal 2012-007526
Application 11/505,039

2

a drain active region of said second conductivity type situated
in said well;
a channel region situated adjacent to a field oxide region
formed over said well;
a gate having a first portion situated over said channel region
and a second portion situated over said field oxide region and said
well;
at least one gate contact situated on said second portion of said
gate;
wherein said second portion of said gate is configured such that
an effective channel width of said channel region extends along
substantiality the entirety of an outer perimeter of said first portion of
said gate; and
wherein said channel region extends to and along said outer
perimeter of said first portion of said gate.
App. Br. 18 (emphasis added).
The claims on appeal stand rejected as follows:
(1) claims 1–5, 8–13, and 15–18 under 35 U.S.C. § 103(a) as
unpatentable over the “Applicant’s Admitted Prior Art (AAPA)”1 in view of
Teshigahara;2 and
(2) claims 6, 7, 14, 19, and 20 under 35 U.S.C. § 103(a) as unpatentable
over AAPA in view of Teshigahara and Olofsson.3
The rejections are sustained for the reasons set forth in the Examiner’s
Answer dated February 15, 2012 (“Ans.”). We add the following for emphasis.
B. DISCUSSION
Referring to the Appellant’s Figure 1, reproduced below, the Examiner finds
that AAPA describes a transistor as recited in claim 1 with the exception of “at

1 Appellant’s Specification 2, ll. 5–20; 5, l. 17–8, l. 14; Fig. 1.
2 US 6,150,697, issued November 21, 2000.
3 US 2001/0004115 A1, published June 21, 2001.
Appeal
Applica

least on
second
said cha
of said f
In
124 pos
Examin
2012-0075
tion 11/50
e gate con
portion of
nnel regio
irst portio
Ap
contrast t
itioned on
er finds th
26
5,039
tact situate
said gate i
n extends
n of said g
pellant’s
o claim 1,
extended
at the effec
d on said
s configur
along subs
ate.” Ans
Figure 1 is
high vol
the Appel
poly segm
tive chann
3
second por
ed such th
tantiality
. 5–6.
a top view
tage transi
lant’s Figu
ent 112. S
el width o
tion of sai
at an effec
the entirety
of a conv
stor.
re 1 show
pec. 6, ll.
f channel
d gate; an
tive chann
of an out
entional
s gate con
13–15. A
region 11
d wherein
el width o
er perimet

tacts 122 a
s a result,
0 only exte
said
f
er
nd
the
nds
Appeal 2012-007526
Application 11/505,039

4

“along most” of the outer perimeter of gate 104 because width 138 is blocked by
extended poly segment 112. Ans. 5; Spec. 7, ll. 17–21. Nonetheless, the Examiner
finds that Teshigahara discloses an analogous transistor comprising a gate contact
and a channel width as recited in claim 1. Ans. 6.
The Examiner concludes that it would have been obvious to one of ordinary
skill in the art to modify the gate contacts and channel region of AAPA as
disclosed in Teshigahara “for the purpose of increasing effective channel width and
relaxing electric field concentration, and thus, improving device performance by
increasing current flow in the transistor device (Teshigahara: col. 4, lines 65-67).”
Ans. 6.
The Appellant does not direct us to any error in the Examiner’s findings of
fact. Rather, the Appellant argues that the disclosure of Teshigahara focuses on
problems that are not present in AAPA, i.e., problems relating to interference
between adjacent electrical components.4 For this reason, the Appellant contends
that one of ordinary skill in the art would not have considered the teachings of
Teshigahara relevant to the transistor of AAPA. App. Br. 11–12.
The Appellant’s argument is not persuasive of reversible error. The
Examiner relies on Teshigahara to solve a problem disclosed in AAPA, i.e.,
reduced drive current within a transistor. See Ans. 12; Spec. 2, ll. 19–20. The fact
that Teshigahara discloses a solution to another unrelated problem, i.e., inter-
component interference, does not weigh against a conclusion of obviousness.
The Appellant also argues that “[a]lleged AAPA expressly discloses that
gate contacts of alleged AAPA are situated on extended poly segment 112 because

4 Teshigahara discloses that inter-component interference may occur between
transistors, namely Lateral Double-diffused MOSFETs. Teshigahara, col. 1, ll.
21–30.
Appeal 2012-007526
Application 11/505,039

5

applicable design rules prevent gate contacts from being situated directly on gate
poly.” App. Br. 13. For this reason, the Appellant contends that AAPA teaches
away from the modification proposed by the Examiner. App. Br. 13–14.
Significantly, the Appellant does not describe the “applicable design rules”
in any detail in the Specification or provide any evidence of the meaning of the
phrase “applicable design rules” to one of ordinary skill in the art.5 Therefore, the
Appellant’s general statement in the Specification that “gate contacts are generally
prohibited from being placed directly on the poly gate by applicable process design
rules” (Spec. 2, ll. 12–14) fails to demonstrate, by a preponderance of the evidence,
that one of ordinary skill in the art would have been discouraged from modifying
AAPA as proposed by the Examiner. See In re Gurley, 27 F.3d 551, 553 (Fed. Cir.
1994) (“A reference may be said to teach away when a person of ordinary skill,
upon reading the reference, would be discouraged from following the path set out
in the reference, or would be led in a direction divergent from the path that was
taken by the applicant.”).
C. CONCLUSION
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)(1).
AFFIRMED

cdc

5 On page 2, lines 13–14 of the Specification, the Appellant refers to “applicable
process design rules” whereas on page 8, line 1 of the Specification, the Appellant
refers to “applicable design rules.”