Ex Parte Parekh et al

Patent Trial and Appeal Board

Aug 17, 2017

14265928 (P.T.A.B. Aug. 17, 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.
14/265,928 04/30/2014 Kunal Parekh 2009-0011.01 ((MICS: 0315-1 4579
52142 7590 08/21/2017
FLETCHER YODER (MICRON TECHNOLOGY, INC.)
P.O. BOX 692289
HOUSTON, TX 77269-2289
EXAMINER
SNOW, COLLEEN ERIN
ART UNIT PAPER NUMBER
2899
NOTIFICATION DATE DELIVERY MODE
08/21/2017 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):
docket@fyiplaw.com
manware@fyiplaw.com
Strickland @ fyiplaw. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KUNAL PAREKH, CEREDIG ROBERTS,
THY TRAN, JIM JOZWIAK, and DAVID HWANG
(Applicant: Micron Technology, Inc.)
Appeal 2017-001470
Application 14/265,92 81
Technology Center 2800
Before ROMULO H. DELMENDO, KAREN M. HASTINGS, and
JAMES C. HOUSEL, Administrative Patent Judges.
PER CURIAM.
DECISION ON APPEAL
A. STATEMENT OF THE CASE
Appellants filed an appeal under 35 U.S.C. § 134(a) from the
Examiner’s decision finally rejecting claims 1—7, 10—13, and 15—19 under
35 U.S.C. § 103(a) as unpatentable over Tang2 in view of Uchiyama.3 We
have jurisdiction under 35 U.S.C. § 6(b).4
1 According to Appellants, the real party in interest is Micron Technology,
Inc. Appeal Br. 2.
2 Tang et al., US 2006/0258084 Al, published Nov. 16, 2006 (“Tang”).
3 Uchiyama, US 2010/0001249 Al, published Jan. 7, 2010 (“Uchiyama”).
4 Our Decision refers to the Appellants’ Specification (Spec.) filed Apr. 30,
2014, the Final Office Action mailed Dec. 31, 2015 (Final Act.), Appellants’
Appeal 2017-001470
Application 14/265,928
We AFFIRM.* * * 5
The subject matter on appeal relates to semiconductor devices (see,
e.g., Spec. 12 and claim 1). Appellants disclose that as semiconductor
devices become smaller, challenges can occur for scaling devices to smaller
footprints and higher densities. Spec. 15. To address this issue, Appellants
disclose a semiconductor device in which a digitline trench is formed in a
substrate substantially beneath a wordline trench and the trenches are
substantially perpendicular to one another. Id. Tflf 10—14, 14, 15.
Independent claim 1 is illustrative and is reproduced below from the
Claims Appendix of the Appeal Brief.6 Limitations at issue are italicized.
1. A device, comprising:
a substrate;
a wordline trench formed in the substrate; and
a digitline trench formed in the substrate, wherein the
digitline trench is substantially perpendicular to the wordline
trench and formed substantially beneath the wordline trench,
and wherein the wordline trench and the digitline trench are
each formed below a surface of the substrate.
B. DISCUSSION
The Examiner finds Tang discloses a device comprising a substrate, a
wordline in a trench in the substrate, and a digitline in a trench in the
substrate, wherein the digitline is substantially beneath the wordline trench
and the trenches are below a surface of the substrate. Final Act. 2. The
Appeal Brief (Appeal Br.) filed June 27, 2016, the Examiner’s Answer
(Ans.) dated Oct. 6, 2016, and Appellants’ Reply Brief (Reply Br.) filed
Nov. 3,2016.
5 Claims 8, 9, 14, and 20 have been indicated as including allowable subject
matter. Final Act. 7.
6 Appeal Br. 12.
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Examiner finds Tang does not disclose that the digitline trench is
substantially perpendicular to the wordline trench. Id. at 3. The Examiner
finds Uchiyama discloses a device including a substrate, a wordline trench in
the substrate, and a digitline trench in the substrate, wherein the digitline
trench is substantially perpendicular to the wordline trench. Id. The
Examiner concludes it would have been obvious to modify Tang in view of
Uchiyama to provide wordline and digitline trenches perpendicular to one
another because Uchiyama teaches that such an arrangement reduces an
overlap region for the trenches, which suppresses electrical interference. Id.
Appellants contend the combination of Tang and Uchiyama does not
disclose or suggest a digitline trench substantially perpendicular to and
substantially beneath the wordline trench, as recited in claim 1. Appeal Br.
6—7. Specifically, Appellants argue claim 1 requires the digitline trench and
the wordline trench to be two different trenches but Tang discloses a single
trench 127 including both a data line 40 (i.e., digitline) and a wordline 95.
Appeal Br. 7—8; Reply Br. 2—6.
Appellants’ arguments are unpersuasive. As an initial matter, we
agree with the Examiner’s finding that claim 1 does not include the language
“a distinct wordline trench” as argued by Appellants8 because this language
was submitted in a proposed amendment dated February 15, 2016 but the
Advisory Action dated March 23, 2016 stated the amendment would not be
entered. Ans. 4.
7 Throughout this Opinion, for clarity, we present labels to elements in
figures in bold font, regardless of their presentation in the original document.
8 Appeal Br. 7, 8, 10.
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Here, Tang discloses a trench 12 that includes a digit line 40 located
beneath wordline 95. Tang || 50, 72 and Figure 8B. The Examiner finds
that the portion of the trench 12 including the digit line 40 functions as a
digitline trench and the portion of the trench 12 including wordline 95
functions as a wordline trench. Ans. 6. Appellants’ arguments do not
identify a reversible error in the Examiner’s finding because claim 1 does
not require that the digitline trench and the wordline trench are non­
overlapping or mutually exclusive. In fact, Appellants assert that although
the trenches are distinct and different, they also argue “these trenches need
not be mutually exclusive” and are “not necessarily wholly independent and
non-overlapping.”9 Reply Br. 4. This is further illustrated by the
requirement in claim 1 that the digitline trench be “substantially beneath” the
wordline trench, which permits overlapping between the trenches in a
vertical direction. Claim 1 does not require the trenches to be non­
overlapping in other directions (e.g., a horizontal direction or a direction
orthogonal to horizontal and vertical directions).
Appellants further assert Uchiyama fails to remedy the deficiencies of
Tang because Uchiyama does not disclose both the perpendicular
arrangement of claim 1 and the digitline trench being substantially beneath
9 With respect to trenches being “distinct,” Appellants argue “to be distinct
from one another the trenches must merely be different trenches and not
necessarily wholly independent and non-overlapping.” Reply Br. 4. Thus,
Appellants’ asserted definition of “distinct” would include overlapping or
non-independent trenches. This would appear to encompass the Examiner’s
interpretation of Tang’s trench 12 as including a portion for a wordline and a
portion for a digitline. Ans. 6. In addition, even if such claim 1 were
interpreted as Appellants urge, Appellants fail to distinguish such distinct
trenches from those shown in Uchiyama.
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Application 14/265,928
the wordline trench, as recited in claim 1. Appeal Br. 9—10. In view of this,
Appellants contend Uchiyama teaches away from a digitline trench being
substantially beneath a wordline trench and one of ordinary skill in the art
would have lacked a reason to modify Tang in view of Uchiyama. Appeal
Br. 10—11; Reply Br. 6—9.
These arguments are also unpersuasive. “[T]he test for combining
references is not what the individual references themselves suggest but
rather what the combination of disclosures taken as a whole would suggest
to one of ordinary skill in the art.” In re McLaughlin, 443 F.2d 1392, 1395
(CCPA 1971).
Here, the Examiner finds Tang discloses the recitations of claim 1,
including a digitline trench substantially beneath a wordline trench, except
for a perpendicular arrangement between the trenches. The Examiner finds
Uchiyama discloses such a perpendicular arrangement and does not rely
upon Uchiyama for a disclosure of a digitline trench being substantially
beneath a wordline trench. Ans. 4—5. The disclosure of Uchiyama supports
the Examiner’s findings by disclosing an arrangement in which:
[t]he bit line and the word line are orthogonally crossed in
different layers respectively so as to reduce the overlapped
region of the two lines as much as possible via an insulating film.
Therefore, the electric interference can be suppressed.
Uchiyama 1 54.
As a result, the combination of the disclosures of Tang and Uchiyama
would have suggested a device arrangement in which a digitline is
substantially beneath and substantially orthogonal to a wordline, as recited in
claim 1. Uchiyama’s disclosure also supports the Examiner’s rationale that
it would have been obvious to modify Tang in view of Uchiyama to use an
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Application 14/265,928
orthogonal arrangement of digitline and wordline trenches to suppress
electrical interference. Although Appellants assert that the suppression of
electrical interference is due to the insulating film, Appellants fail to direct
our attention to any support in Uchiyama or elsewhere in the record for this
assertion. Reply Br. 7. Indeed, paragraph 54 of Uchiyama states the
orthogonal arrangement reduces an overlapping region for wordline and
digitline as much as possible and this results in the suppression of electrical
interference. Paragraph 54 of Uchiyama states that the insulating film is
present between the trenches in the overlapping region, not that it alone
suppresses electrical interference.
We also note that paragraph 53 of Uchiyama states:
As illustrated by arrows in two directions in FIG 2, trenches
extending in two different directions are formed. These trenches
are different in depth and cross each other. Preferably, as
illustrated in Fig. 2, these trenches are orthogonal.
Therefore, Uchiyama discloses a wordline and a digitline in separate
trenches and thus provides further support that an orthogonal arrangement of
a wordline trench and a digitline trench were known in the art. In addition,
claim 1 does not recite a reference for the top or bottom of the claimed
device. Therefore, one may interpret Uchiyama as disclosing a digitline
trench substantially beneath a wordline trench by inverting the device
depicted in Figure 2 of Uchiyama. Thus, the shallow trench containing the
digitline would be closer to the bottom of the device and beneath the deep
trench that includes the wordline.
We further note that the claims are rejected over the combination of
Tang and Uchiyama. Whether the Examiner listed Tang as the primary
reference or Uchiyama as the primary reference is irrelevant. See In re
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Application 14/265,928
Bush, 296 F.2d 491, 496 (CCPA 1961) (“In a case of this type where a
rejection is predicated on two references each containing pertinent disclosure
which has been pointed out to the applicant, we deem it to be of no
significance, but merely a matter of exposition, that the rejection is stated to
be on A in view of B instead of on B in view of A, or to term one reference
primary and the other secondary.”). For instance, claim 1 could be
considered rejected over Uchiyama in view of Tang, with Uchiyama
disclosing separate, orthogonal trenches for a wordline and digitline and
Tang disclosing the digitline trench substantially beneath the wordline
trench.
Uchiyama’s disclosure alone also demonstrates the obviousness of the
device of claim 1. As stated above, Uchiyama discloses separate, orthogonal
trenches for a wordline and digitline, which are beneath a surface of a
substrate, and one may interpret the digitline trench as being beneath the
wordline trench because claim 1 does not recite any reference for the top or
bottom of the substrate, as noted above. Moreover, to the extent one
considers the digitline trench of Uchiyama as being above its wordline
trench, it would have been obvious to one of ordinary skill in the art to
arrange the digitline trench either above or below the wordline trench as
these are the only options available for their arrangement. “A person of
ordinary skill is also a person of ordinary creativity, not an automaton.”
KSRInt'l. Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007). Such a
rearrangement of Uchiyama’s digitline trench below the wordline trench
would have been within the capabilities of one of ordinary skill in the art.
Appellants do not argue independent claims 11 and 17 or dependent
claims 2—7, 10, 12, 13, 15, 16, 18, and 19 separately from claim 1. Appeal
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Application 14/265,928
Br. 6—11. For the reasons discussed above and those set forth in the
Examiner’s Answer, we sustain the Examiner’s § 103 rejection of claims
1—7, 10-13, and 15—19 over the combination of Tang and Uchiyama.
C. DECISION
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
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