Ex Parte Chen et al

Patent Trial and Appeal Board

Feb 28, 2017

13273026 (P.T.A.B. Feb. 28, 2017)

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.
13/273,026 10/13/2011 Gang Chen 4320P269 3268
62294 7590
BSTZ-OVT
1279 Oakmead Parkway
Sunnyvale, CA 94085-4040
EXAMINER
GUPTA, RAJ R
ART UNIT PAPER NUMBER
2829
NOTIFICATION DATE DELIVERY MODE
03/02/2017 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
FIP_Group @bstz. com
docketing @ ovt. com
j es sic a_raucci @ bstz. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte GANG CHEN, SING-CHUNG HU, HSIN-CHIH TAI,
DULI MAO, MANOJ BIKUMANDLA, WEI ZHENG, YIN QIAN,
ZHIBIN XIONG, VINCENT VENEZIA, KEH-CHIANG KU, and
HOWARD E. RHODES
Appeal 2015-007221
Application 13/273,026
Technology Center 2800
Before ADRIENE LEPIANE HANLON, ROMULO H. DELMENDO, and
MICHAEL G. McMANUS, Administrative Patent Judges.
McMANUS, Administrative Patent Judge.
DECISION ON APPEAL
The Examiner finally rejected claims 1—16 of Application 13/273,026
(“’026 Application”) under 35 U.S.C. § 103(a) as obvious. Final Act. 3—8
(Oct. 7, 2014). Appellants1 seek reversal of these rejections pursuant to
35 U.S.C. § 134(a). We have jurisdiction under 35 U.S.C. § 6.
For the reasons set forth below, we reverse.
1 OmniVision Technologies, Inc. is identified as the real party in interest.
Appeal Br. 2.
Appeal 2015-007221
Application 13/273,026
BACKGROUND
The ’026 Application describes an image sensor pixel that includes a
photosensitive element, a floating diffusion region, and a transfer device.
Spec., Abst.
Claim 1 is representative of the application’s claims and is reproduced
below with a portion relevant to the following discussion in bolded text:
1. An image sensor pixel, comprising:
a photosensitive element disposed in a substrate layer for
accumulating an image charge in response to light;
a floating diffusion ("FD") region disposed in the substrate
layer to receive the image charge from the photosensitive
element; and
a transfer device disposed between the photosensitive element
and the FD region to selectively transfer the image charge from
the photosensitive element to the FD region, the transfer device
including:
a buried channel device including a buried channel
gate disposed over a buried channel dopant region;
and
a surface channel device in series with the buried channel
device, the surface channel device including a surface
channel gate disposed over a surface channel region,
wherein the surface channel gate has the opposite doping
polarity of the buried channel gate.
Appeal Br. 9 (Claims App.) (emphasis added).
REJECTION
On appeal, the Examiner maintains the following rejection:
Claims 1—16 are rejected under 35 U.S.C. § 103(a) as unpatentable
over the combination of Adkisson et al. (US 2008/0128767 Al,
pub. June 5, 2008) (hereinafter “Adkisson”) and Gambino et al.
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Appeal 2015-007221
Application 13/273,026
(US 2008/0179639 Al, pub. July 31, 2008) (hereinafter
“Gambino”). Final Act. 3—8.
DISCUSSION
The Examiner rejected each claim as obvious over Adkisson in view
of Gambino. The Examiner relies upon Adkisson for, inter alia, its teaching
of “a buried channel device including a buried channel gate,” Final Act. 3,
and Gambino as teaching that the buried channel gate is “disposed over a
buried channel dopant region,” id. at 4. Figure 2 of Gambino is reproduced
below:
100
125
\
200
127
180 170
\ A
23a
II \
5pa V
50c
126
.12
T-1...V- TTT"
'3 23b 130\
r....
.. V J E4— ................................................
•. ' \ 1
..............
..... A
”1 190i 1? 0 \ \ 35
j /
/' \
\ 50b Ns iso
5 /
172s'
124
172b A
15
Gambino, Fig. 2. Figure 2 depicts gate structure 125 and doped region 172b.
Appellants argue that Gambino teaches neither a buried channel gate
nor a buried channel dopant region and, therefore, does not teach a buried
channel device. Appeal Br. 6. The thrust of Appellants’ argument is that
Gambino does not teach a buried channel. Rather, in Appellants’ view, it
teaches a charge collection region 170 (which may also be viewed as a
“source”) connected to a floating diffusion region 130 (which may also be
viewed as a “drain”) by a surface channel. Id. at 6.
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Appeal 2015-007221
Application 13/273,026
Appellants offer three arguments in support of their view. First, they
state that Gambino itself describes region 172b as a portion of the charge
collection well 170 and describes a separate structure as “transfer gate
channel region 160.” Appeal Br. 5—6; Gambino 120. Second, they argue
that arrow 124, which designates “path of charge transfer” in Gambino,
indicates charge transfer within charge collection region 170 rather than a
channel structure that connects the source and the drain. Id. at 6. Third,
Appellants assert that charge carriers may flow from portion 172a of
Gambino to 172b even while gate 125 is not enabled. They assert that this
corroborates their view that element 172b is not part of a channel as charge
flows through a channel only when the device is enabled. Id.
Accordingly, they reason, Gambino lacks a buried channel and,
therefore, a buried channel gate and a buried channel dopant region. Id.
In the Answer, the Examiner asserts that charge transfer path 124
forms a buried channel. Answer 3. In support, the Examiner asserts that it
is reasonable to view Gambino’s element 172a (the left side of the collection
well 170 which has a greater concentation of dopant) as the source and
element 172b (the right side of collection well 170 which has a lesser
concentration of dopant) as a channel. Answer 4.
The Examiner’s construction, however, requires that element 172b of
Gambino be designated as both the claimed “buried channel dopant region”
as well as a buried channel (charge transfer path 124 is indicated as within
element 172b). It is apparent from the Specification and Drawings of the
present application that the buried channel dopant region serves to
accumulate charge carriers while the transfer device (gate) is off. Spec. 1
30. The buried channel (designated 460 in the Drawings and Specification)
serves as a path toward the surface channel and, subsequently, the floating
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Appeal 2015-007221
Application 13/273,026
diffusion region upon application of a voltage from the gate. Id. ^ 31.
Region 172b of Gambino cannot be considered both of these structures.
Accordingly, we do not adopt the Examiner’s findings regarding the scope
of Gambino’s disclosure, and consequently, cannot affirm.
CONCLUSION
For the reasons set forth above, the rejection of claims 1—16 of the
’026 Application as obvious is reversed.
REVERSED
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