Ex Parte CHOI

Patent Trials and Appeals Board

Jun 17, 2019

14692017 - (D) (P.T.A.B. Jun. 17, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/692,017 04/21/2015
23494 7590 06/19/2019
TEXAS INSTRUMENTS IN CORPORA TED
PO BOX 655474, MIS 3999
DALLAS, TX 75265
FIRST NAMED INVENTOR
Y ounsung CHOI
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
TI-74113 1715
EXAMINER
YUSHINA, GALINA G
ART UNIT PAPER NUMBER
2811
NOTIFICATION DATE DELIVERY MODE
06/19/2019 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):
uspto@ti.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL
AND APPEAL BOARD
Ex parte YOUNSUNG CHOI
Appeal 2018-006360
Application 14/692,017
Technology Center 2800
Before ROMULO H. DELMENDO, MICHAEL P. COLAIANNI, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
COLAIANNI, Administrative Patent Judge.
DECISION ON APPEAL
Appeal 2018-006360
Application 14/692,017
Appellant1 appeals under 35 U.S.C. § 134 the final rejection of claims
1, 3-10, 19, and 20. We have jurisdiction over the appeal pursuant to
35 U.S.C. § 6(b).
We AFFIRM-IN-PART.
Appellant's invention is directed top-type metal-oxide-semiconductor
field effect transistor (PFET). (Spec. ,r 3; claim 1 ).
Claim 1 is illustrative of the subject matter claimed:
1. A p-type metal-oxide-semiconductor field effect
transistor (PFET), comprising:
a p-type silicon substrate;
an n-type well formed in the p-type silicon substrate;
a p-type source formed in then-type well;
a p-type drain formed in then-type well; and
dual pockets formed in then-type well laterally
extending from the source to the drain, the dual pockets
comprising a first pocket with first arsenic n-type dopants
directly below an n-type area for a channel and a second pocket
with second arsenic n-type dopants below the first pocket,
wherein the first pocket has a higher arsenic n-type doping
concentration than the second pocket and both the first pocket
and the second pocket have a higher n-type doping than then-
type well region.
Appellant appeals the following rejections:
1. Claims 1, 3, and 5 are rejected under 35 U.S.C. § 103 as unpatentable
over Hoffmann (US 2014/0084385 Al, published Mar. 27, 2014) in
view ofMasuoka (US 2006/0081943 Al, published Apr. 20, 2006)
and Bakhishev (US 9,299,801 Bl, issued Mar. 29, 2016).
1 The Appeal Brief on page 3 indicates that "Texas Instruments
Incorporated" is the assignee of record, which is also identified as Applicant
(Application Data Sheet filed April 21, 2015, 4).
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Application 14/692,017
2. Claims 4, 6-8, 19, and 20 are rejected under 35 U.S.C. § 103 as
unpatentable over Hoffmann in view of Masuoka, Bakhishev, and
Chindalore (US 2004/0070030 Al, published Apr. 15, 2004).
3. Claims 9 and 10 are rejected under 35 U.S.C. § 103 as unpatentable
over Hoffmann in view ofMasuoka, Bakhishev, Chindalore, and
Chang (US 2006/0157774 Al, published July 20, 2006).
FINDINGS OF FACT & ANALYSIS
Rejection (1)
Appellant's arguments focus on the subject matter of claim 1 only
(App. Br. 4--5). Claims 3 and 5 will stand or fall with our analysis of the
rejection of claim 1.
The Examiner's findings and conclusions regarding Hoffmann,
Bakhishev and Masuoka are located on pages 3-7 of the Final Office Action.
Appellant argues that there is no disclosure in the combined teachings
of Hoffmann, Masuoka, and Bakhishev of dual pockets formed in the n-type
well laterally extending from the source to the drain, wherein the first pocket
has a higher arsenic n-type doping concentration than the second pocket and
both the first pocket and the second pocket have a higher n-type doping than
then-type well region (App. Br. 4). Appellant contends that Hoffmann
teaches a highly doped screening layer 112 below a threshold voltage set
region 111, which is contrary to the claim limitations (App. Br. 4).
Appellant argues that even though the concentration ranges for Hoffmann's
threshold voltage region 111 and screening layer 112 overlap, Hoffmann
teaches that the threshold voltage region 111 may have a dopant
concentration that is approximately one-third to one-half of the screen region
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Application 14/692,017
112 (App. Br. 5). Appellant contends that Hoffmann does not teach that a
first pocket has a higher arsenic n-type doping concentration than a second
pocket (App. Br. 5). Appellant argues that Bakhishev is directed to reducing
migration of high diffusible dopant such as boron (App. Br. 5). Appellant
contends that one of ordinary skill in the art would not look to Bakhishev to
address a lower diffusible dopant such as arsenic (App. Br. 5). Appellant
argues that although Bakhishev teaches that the screening layer may have a
higher, lower, or the same dopant concentration as threshold set layer,
Bakhishev provides no guidance on which option to use (App. Br. 5).
Contrary to Appellant's arguments, the Examiner finds and Appellant
concedes that Hoffmann' s dopant concentration ranges for the threshold
voltage region 111 and screening layer 112 overlap one another (Final Act.
3; Ans. 6; App. Br. 5). The Examiner finds that Hoffmann teaches that
layers 111 and 112 are doped to achieve a desired threshold voltage for the
device (Ans. 6). In light of that teaching and the overlapping dopant
concentrations for the screening layer 112 and the threshold voltage layer
111 in Hoffmann, the Examiner determines that it would have been within
the skill of the ordinary artisan to have included in the screening layer 112
more dopant than in the threshold voltage layer 111 (Ans. 6). The Examiner
correctly finds that Hoffman's teaching of the voltage threshold layer 111
containing 1h to 1h of the dopant concentration of the screening layer 112 is
an alternative disclosure of how the dopant concentrations can be set, but
which does not limit Hoffmann's broader teaching that the desired threshold
voltage determines the dopant concentrations for the threshold voltage layer
111 (see Ans. 6-7 ( citing to Hoffman ,r 31) ). The Examiner further finds
that Bakhishev's teachings that the dopant concentration of the screen layer
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Application 14/692,017
312 may be higher than, lower than or the same as the dopant concentration
of the threshold voltage layer 314 in Bakhishev's device (Ans. 7-8). The
Examiner finds that the combined teachings of Hoffmann, Masuoka and
Bakhishev would have suggested the claimed dual pocket layer with the
arsenic dopant concentrations as recited in the claims (Ans. 7-8).
Appellant does not address with any specificity the Examiner's
findings regarding Hoffmann's teachings that the desired threshold voltage
would determine the suitable dopant concentrations in the screening layer
112 and threshold voltage layer 111 (Reply Br. 1-3). Rather, Appellant
maintains that Hoffmann teaches that the dopant concentration in the
threshold voltage layer 111 is limited to being 1/ 3 or 1h of the dopant
concentration in the screening layer 112 (Reply Br. 2). This argument is
unpersuasive for the reasons discussed above.
Appellant argues that Bakhishev's teachings that the dopant
concentrations of the screening layer 312 may be the same as, higher than, or
lower than the dopant concentration of the threshold voltage layer 314, is
directed to a switch in the relative position of the layers 312 and 314 (Reply
Br. 3). Bakhishev teaches:
In alternative embodiments, screening layer 312 may have a
higher dopant concentration, approximately the same, or lower
dopant concentration than that of threshold voltage set layer
3 14 so that the screening layer 3 12 may be below or above the
threshold voltage set layer 314.
(Col. 4, 11. 59---64).
While Bakhishev's disclosure states that the positional relationship of
the layers may be modified due to the differences in dopant concentration,
that disclosure does not change Bakhishev's teaching that the relative dopant
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Appeal 2018-006360
Application 14/692,017
concentration between the screening layer 312 and threshold voltage set
layer 314 may be different relative to one another. We agree with the
Examiner that the combined teachings of Hoffmann, Masuoka, and
Bakhishev would have suggested the subject matter of claim 1.
On this record, we affirm the Examiner's§ 103 rejection of claim 1.
Rejection (2)
Appellant separately argues the subject matter of claims 7 and 19
(App. Br. 6). Appellant does not provide any substantive arguments against
claims 4, 6, and 8 other than to argue that Chindalore does not cure the
alleged deficiencies argued with respect to claim 1 (App. Br. 6). Thus,
claims 4 and 6 stand or fall with claim 1 for the reasons given above and
claim 8 stands or falls with claim 7. Claim 20 depends from claim 19 and
will stand or fall with our analysis of the rejection of claim 19.
Appellant argues with regard to claim 7 that there is no disclosure or
suggestion in the combination of first and second lightly-doped drain (LDD)
regions on the first and second pockets (App. Br. 6). Appellant argues that
Hoffmann's LDD regions SDE 132 are spaced from the threshold voltage
layer 111 (App. Br. 6; Reply Br. 3).
The Examiner finds that Hoffmann teaches that the LDD regions 132
are formed on the set layer 111 and screening layer 112 (Final Act. 10). The
Examiner finds that Hoffmann's SDE regions are formed on the set layer
111 and screening layer 112 (Ans. 9). The Examiner also finds that
Bakhishev teaches that the LDD regions 322 are disposed on set layer 314
and screening layer 312 (Ans. 9).
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Application 14/692,017
Although Appellant maintains that a space is formed between
Hoffmann's LDD region (SDE) and the set threshold layer 111 and
screening layer 112 so that the SDE region is not on the set layer 111 and
screening layer 112, Appellant does not direct us to a definition of the term
"on" in claim 7 that would exclude a space or intervening layer between the
LDD region and the first and second pockets. On this record, Appellant has
not shown reversible error in the Examiner's rejection of claim 7.
With respect to claim 19, Appellant argues that Hoffmann fails to
teach that set layer 111 (i.e., first pocket) is directly below the SDE region
(i.e., LDD region) (App. Br. 6). Appellant argues that the prior art has a
space between the LDD and the set layer 111 (Reply Br. 3). We agree.
Claim 19 requires that the first pocket is directly below the LDD
region. The Examiner relies on Chindalore to teach a first pocket is directly
below the LDD region (Final Act. 14; Ans. 10-11). The Examiner finds
erroneously that Chindalore' s isolation trenches 22 and 24 are the source and
drain and source 51 and drain 53 are the LDD regions (Ans. 10-11). The
Examiner finds that Chindalore's extensions of the source 51 and drain 53
are directly above the first pocket 74 (i.e., anti-punch through layer) as
shown in Figure 8 ofChindalore (Ans. 11). The source 52 and drain 54 are
connected to extensions 51 and 53 (Chindalore's Figure 8). Appellant
argues persuasively that there is a space formed between the extensions 51
and 53, and Chindalore's anti-punch through layer 74, which the Examiner
finds corresponds to the claimed first pocket (Reply Br. 4). The Examiner
has not shown that entire source 52 or drain 54 is LDD region. Rather, the
Examiner finds that there is only two options for the positioning of the LDD
region and the first pocket: either directly below or spaced from it (Final
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Application 14/692,017
Act. 14 ). The Examiner finds that it would have been obvious to try both
options and determine which one provides a more reliable transistor (Final
Act. 14).
The obvious to try rationale requires a design need or a market
pressure to solve a problem and a finite number of predictable solutions.
KSR International Co. v. Teleflex, Inc., 550 U.S. 398,421 (2007) ("The
same constricted analysis led the Court of Appeals to conclude, in error, that
a patent claim cannot be proved obvious merely by showing that the
combination of elements was ' [ o ]bvious to try.' When there is a design need
or market pressure to solve a problem and there are a finite number of
identified, predictable solutions, a person of ordinary skill has good reason
to pursue the known options within his or her technical grasp. If this leads
to the anticipated success, it is likely the product not of innovation but of
ordinary skill and common sense. In that instance the fact that a
combination was obvious to try might show that it was obvious under
§ 103."). The Examiner has not shown where each of the two options (i.e., a
"first pocket directly below the first LDD and the second LDD" or an
intermediate spacing layer between the LDD and the first pocket) are taught
in the prior art as predictable solutions to address a design need. The
Examiner has not established that there was a design need or market
pressure to solve a particular problem and a predictable solution to that
problem included placing the first and second pockets directly below the
LDD region. The Examiner has not shown that Chindalore's extension
regions 51 and 53 are LDD regions. Chindalore teaches that the regions 51
and 53 are extensions of source and drain regions 52 and 54 (i-f 42).
Accordingly, the Examiner's conclusion based on the obvious to try
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rationale fails to establish a prima facie case obviousness with respect to
claim 19. Therefore, we cannot sustain the Examiner's§ 103 rejection of
claims 19 and 20 over Hoffmann in view of Masuoka, Chindalore and
Bakhishev.
Rejection (3)
Appellant relies on the arguments regarding claim 1 with regard to the
§ 103 rejection of claims 9 and 10 over Hoffmann in view of Masuoka,
Chindalore, Bakhishev and Chang. Because we find Appellant's arguments
regarding claim 1 to be unpersuasive of reversible error, we affirm the
Examiner's§ 103 rejection of claims 9 and 10 for the same reasons.
On this record, we affirm the following Examiner's§ 103 rejections:
(1) claims 1, 3, and 5 over Hoffmann in view ofMasuoka, and Bakhishev,
and (2) claims 4 and 6-8 over Hoffmann in view of Masuoka, Bakhishev
and Chindalore, and (3) claims 9 and 10 over Hoffmann in view of
Masuoka, Chindalore, Bakhishev, and Chang.
We reverse the Examiner's§ 103 rejection of claims 19 and 20 over
Hoffmann in view of Masuoka, Bakhishev and Chindalore.
DECISION
The Examiner's decision is affirmed-in-part.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l )(iv). See 37
C.F.R. § 41.50(±).
ORDER
AFFIRMED-IN-PART
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