Ex Parte Chen et al

Patent Trial and Appeal Board

Sep 23, 2016

12960411 (P.T.A.B. Sep. 23, 2016)

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.
12/960,411 12/03/2010 Chun CHEN SPN10064 7146
105945 7590 09/23/2016
Sterne, Kessler, Goldstein & Fox P.L.L.C.
1100 New York Avenue, NW
Washington, DC 20005
EXAMINER
KALAM, ABUL
ART UNIT PAPER NUMBER
2896
MAIL DATE DELIVERY MODE
09/23/2016 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte CHUN CHEN, ANGELA T. HUI, and FEI WANG
____________________

Appeal 2015-004545
Application 12/960,411
Technology Center 2800
____________________

Before ROMULO H. DELMENDO, JULIA HEANEY, and
BRIAN D. RANGE, Administrative Patent Judges.

RANGE, Administrative Patent Judge.

DECISION ON APPEAL

SUMMARY
Appellants1 appeal under 35 U.S.C. § 134(a) from the Examiner’s
decision rejecting claims 1–15. We have jurisdiction. 35 U.S.C. § 6(b).
We AFFIRM.

1 According to the Appellants, the real party in interest is Spansion LLC. Br.
3.
Appeal 2015-004545
Application 12/960,411
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STATEMENT OF THE CASE
Appellants describe the present invention as relating to computer-
readable memory and, in particular, NAND flash memory (with NAND
referencing a negative-AND logic gate) having a recessed source/drain
region between a selective gate and an edge word line. Spec. 1:6–8. Claim
1, reproduced below with emphasis added, is illustrative of the claimed
subject matter:
1. A device for storing information, comprising:
a NAND flash memory array, including:
a cell body;
a first selective gate disposed above the cell body;
and
a first edge word line gate,
wherein the cell body includes a first doped source/drain
region between the first selective gate and the first edge word
line gate,
wherein at least a portion of the first doped source/drain
region is recessed relative to a portion of the cell body that is
below the first selective gate, and
wherein a dopant concentration of a portion of the first
doped source/drain region directly beneath the recessed
portion of the first doped source/drain region is greater than
a dopant concentration in a second doped source/drain
region of the cell body.
Br.2 17 (Claims Appendix).

2 In this decision, we refer to the Final Office Action mailed February 25,
2014 (“Final Act.”), the Appeal Brief filed September 29, 2014 (“Br.”), and
the Examiner’s Answer mailed January 13, 2015 (“Ans.”).
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Application 12/960,411
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REFERENCES
The Examiner relied upon the prior art below in rejecting the claims
on appeal:
Furuhata US 6,673,678 B2 Jan. 6, 2004
Lee et al.
(hereinafter “Lee”)
US 2007/0001212 A1 Jan. 4, 2007
REJECTIONS
The Examiner maintains the following rejections on appeal:
Rejection 1. Claims 1–15 under 35 U.S.C. § 112, first paragraph, as
failing to comply with the written description requirement. Final Act. 2.
Rejection 2. Claims 1–15 under 35 U.S.C. § 103 as unpatentable over
Lee in view of Furuhata. Id. at 3.
ANALYSIS
We review the appealed rejections for error based upon the issues
identified by Appellants and in light of the arguments and evidence produced
thereon. Cf. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010)
(precedential) (cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed.
Cir. 2011) (“it has long been the Board’s practice to require an applicant to
identify the alleged error in the examiner’s rejections”)).
Rejection 1. Pursuant to the written description requirement of
35 U.S.C. § 112, first paragraph, the disclosure of the application relied upon
must “reasonably convey[] to those skilled in the art that the inventor had
possession of the claimed subject matter as of the filing date.” Ariad
Pharms., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (en
banc). Our reviewing court has explained:
[T]he hallmark of written description is disclosure. Thus,
“possession as shown in the disclosure” is a more complete
formulation. Yet whatever the specific articulation, the test
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Application 12/960,411
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requires an objective inquiry into the four corners of the
specification from the perspective of a person of ordinary skill
in the art. Based on that inquiry, the specification must describe
an invention understandable to that skilled artisan and show that
the inventor actually invented the invention claimed.
Id. The written description inquiry is a question of fact. Id.
Here, the Examiner determines that the Specification lacks written
description support for claim 1’s recitation “wherein a dopant concentration
of a portion of the first doped source/drain region directly beneath the
recessed portion of the first doped source/drain region is greater than a
dopant concentration in a second doped source/drain region of the cell
body.” Final Act 2–3. In particular, the Examiner finds that the
Specification (1) does not state that “the additional doping implant is added
to the region directly beneath the recessed portion,” (2) does not state what
type of doping implant is added thus leaving unclear whether the additional
doping would increase or decrease dopant concentration where it is added,
and (3) does not state that the additional doping is added exclusively to only
a first source/drain region and not the second source/drain region. Id. at 3.
Appellants contend that written description for the recitation is
provided by Figure 9 and the Specification’s discussion of Figure 9. Figure
9 with Appellants’ annotations added, as it appears at page 10 of the Appeal
Brief, is reproduced below.
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Figure 9 illustrates an embodiment of the NAND memory cell column after
silicon recess etch. Spec. 2:18–19. Appellants have drawn ovals around
source/drain regions, and the recesses are apparent. Br. 10. The
Specification explains that the “spacers provide protection so that only the
portion of the source/drain region that is desired to be etched is etched.”
Spec. 11:25–27. The Specification also explains that the caps indicated in
Figure 9 serve “to protect the gates from spacer etch in a subsequent stage.”
Id. 11:3–4. Most pertinent to the written description issue at hand, the
Specification states that “an additional doping implant may be added to the
source/drain region after creating the recession.” Id. at 11:30–31 (emphasis
added).
Appellants argue that the term “additional” (emphasized above) refers
back to the original dopant implant that created the source/drain regions such
that the additional implant necessarily leads to greater dopant concentration
(as opposed to cancelling out already existing dopant concentration) or,
alternatively, that a person of skill would recognize that applying a dopant
that would cancel the first charge would not make sense. Br. 9. Appellants
also argue that any additional dopant added to the substrate of Figure 9
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would result in only depositing dopant in the recessed regions “as the caps
and spacers depicted in Figure 9 form an implantation barrier that would
prevent the additional dopant from being deposited in other source/drain
regions.” Id. at 10.
The Examiner responds by stating that nothing in the Specification
suggests the “additional dopant” refers back to the original implant and that
“it is well-known and conventional in the art to use opposite types of dopant
implants in and around the source/drain regions to form pocket halo regions
and source/drain extensions.” Ans. 3. The Examiner explains that the
spacer is not an implant barrier because “it is well known and conventional
in the art that dopants can be implanted through a spacer.” Id. at 4. The
Examiner further notes that “additional dopant implant can be added to the
sidewalls of the recessed portion using conventional angle implantation
techniques.” Id.
The question at hand is whether, when viewing the Specification
including the passages and figure identified by Appellants, a person of
ordinary skill in the art would have recognized that Chen et al. possessed
“wherein a dopant concentration of a portion of the first doped source/drain
region directly beneath the recessed portion of the first doped source/drain
region is greater than a dopant concentration in a second doped source/drain
region of the cell body.” Because the Examiner presented a prima facie case
and the Appellants submitted responsive argument, “[compliance with 35
U.S.C. § 112] is determined on the totality of the record, by a preponderance
of the evidence with due consideration to persuasiveness of argument.” Cf.
In re Alton, 76 F.3d 1168, 1175 (Fed. Cir. 1996). The present record makes
the question at hand particularly difficult to resolve because of the paucity of
evidence both the Examiner and Appellants present. For example, each side
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takes an opposite view of whether spacers are implant barriers but neither
side presents evidence to prove their respective position.
The Specification, as a whole, teaches that the additional dopant will
be applied, at least in part, to the region just below the etched recesses. The
Specification, as a whole, indicates that Chen et al. recognized the same
dopant could be used as the additional dopant. Final Act 3 (stating that
Specification is “unclear whether or not this additional doping implant will
increase or decrease the dopant concentration”). Based on the present
record, it appears that a person of skill, including Chen et al., would have
recognized that the additional dopant would have been at least unevenly
distributed because of the presence of spacers and caps and would have
recognized that a greater amount of the additional dopant would reach the
areas not covered by spacers and caps. In particular, the Examiner does not
appear to dispute the Appellants’ argument that caps serve as an implant
barrier. Also, the Specification does not reference angle implementation
techniques so there is no reason to believe Chen et al.’s description of
additional doping means only employing such techniques to ensure perfectly
even dopant distribution. Thus, on balance, we find that the preponderance
of evidence and persuasiveness of arguments do not weigh in favor of
sustaining the Examiner’s rejection of claims 1–15 under 35 U.S.C. § 112,
first paragraph based on the present record.
Rejection 2. The Examiner rejects claims 1–15 as obvious over Lee in
view of Furuhata. Final Act. 3. Appellants do not separately argue claims
2–15. We therefore limit our discussion to claim 1. Claims 2–15 stand or
fall with that claim. 37 C.F.R. § 41.37(c)(1)(iv) (2013).
After having considered the evidence presented in this Appeal and
each of Appellants’ contentions, we affirm the Examiner’s obviousness
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rejection for the reasons expressed in the Final Office Action and the
Answer because we are not persuaded that Appellants identify reversible
error. We add the following primarily for emphasis.
The Examiner finds that Lee discloses all limitations of claim 1 except
for explicitly disclosing “wherein the dopant concentration of a portion of
the first source/drain region directly beneath the recessed portion in the first
doped source/drain region is greater than the dopant concentration in a
second doped source/drain region of the cell body.” Final Act. 4; see also
e.g., Lee Fig. 5, ¶¶ 11, 49, 53, 60. The Examiner finds that Furuhata teaches
this limitation and concludes that it would have been obvious to combine the
teachings of Furuhata with Lee “for the purpose of lowering the diffusion
resistance below the recessed region, and thus, improving device
characteristics and performance.” Final Act. 5; see also Furuhata 3:1–11;
see also Furuhata 2:58–67 (explaining that high diffusion resistance “slows
the speed of programming, erasing, and reading of the memory element”).
Appellants argue that modification of Lee with Furuhata’s teachings
would make the device more susceptible to the punch-through effect that
Lee seeks to avoid. Br. 13. Appellants admit, however, that “punch-through
effects and performance present a well-known tradeoff . . . .” Id. at 14.
Appellants also argue that Furuhata’s solutions for addressing the punch
through effect present additional challenges. Id. at 14–15.
The problem with Appellants’ argument is that it does not
persuasively rebut the Examiner’s finding that a person of skill would have
applied Furuhata’s teachings to Lee in order to improve performance. Ans.
7–8. As the Examiner finds, Lee does not require total elimination of punch
through. Ans. 6; Lee ¶ 6. Some increased vulnerability to punch through
will not obviate motivation to combine where a person of skill would have
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recognized that the combination could provide increased performance.
Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1165 (Fed. Cir. 2006) (“[A]
given course of action often has simultaneous advantages and disadvantages,
and this does not necessarily obviate motivation to combine”). On balance,
we agree with the Examiner (Ans. 6–8) that a preponderance of the evidence
supports that a person of skill would have accepted some additional
possibility of punch through effects in order to obtain better performance by
implementation of Furuhata’s teachings. This is especially true given
Furuhata’s teachings explicit teachings regarding mitigation of punch
through effects. Ans. 5; Furuhata 15:49–57.
We thus sustain the Examiner’s obviousness rejection of claims 1–15.
DECISION
For the above reasons, we reverse the Examiner’s rejection of claims
1–15 under 35 U.S.C. § 112, first paragraph, as failing to comply with the
written description requirement. We affirm the Examiner’s rejection of
claims 1–15 under 35 U.S.C. § 103.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED