Ex Parte Kim et al

Patent Trial and Appeal Board

Aug 14, 2018

13782106 (P.T.A.B. Aug. 14, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/782,106 03/01/2013
123187 7590
Williams Morgan, P.C.
710 N. Post Oak Road
Suite 350
Houston, TX 77024
08/14/2018
FIRST NAMED INVENTOR
Hoon Kim
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.
DU372/4014.248700 7434
EXAMINER
PIZARRO CRESPO, MARCOS D
ART UNIT PAPER NUMBER
2814
MAIL DATE DELIVERY MODE
08/14/2018 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 HOON KIM and KISIK CHOI 1
Appeal 2018-001014
Application 13/782, 106
Technology Center 2800
Before BRADLEY R. GARRIS, CHRISTOPHER C. KENNEDY, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
GARRIS, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134, Appellant appeals from the Examiner's
rejections under 35 U.S.C. § 103(a) of independent claims 1, 11, and 21 as
unpatentable over Jiang (US 2013/0105919 Al; published May 2, 2013) in
view of Brown (US 2012/0228773 Al; published Sep. 13, 2012) and of
remaining dependent claims 2, 3, 7, 8, 12, 13, 17, 18, and 22-26 as
unpatentable over these references alone or in combination with additional
prior art. We have jurisdiction under 35 U.S.C. § 6.
We AFFIRM.
1 Appellant is the Applicant Globalfoundries, Inc., which is identified as the
real party in interest (App. Br. unnumbered 2).
Appeal 2018-001014
Application 13/782,106
Appellant claims a semiconductor structure comprising a substrate
102, a dielectric layer 118 on the substrate, an unoxidized titanium nitride
layer 122 on the dielectric layer, and a hafnium carbide barrier layer 124 on
the unoxidized titanium nitride layer (independent claim 1, Fig. 3B; see also
remaining independent claims 11 and 21 ). According to Appellant's
Specification, the hafnium carbide ( or a tantalum carbide) layer 124 prevents
the titanium nitride layer 122 from oxidizing (Spec. ,r,r 29--30).
A copy of representative claim 1, taken from the Claims Appendix of
the Appeal Brief, appears below.
1. A semiconductor structure, comprising:
a semiconductor substrate;
a dielectric layer disposed on the semiconductor
substrate;
a gate trench structure formed in the dielectric layer, the
gate trench structure having walls and a bottom;
an unoxidized titanium nitride layer disposed on, and in
direct physical contact with the dielectric layer, the unoxidized
titanium nitride layer being deposited over substantially an
entirety of the walls and the bottom of the gate trench structure;
a hafnium carbide barrier layer disposed on, and in direct
physical contact with the unoxidized titanium nitride layer, the
hafnium carbide barrier layer being deposited over substantially
an entirety of the unoxidized titanium nitride layer on the walls
and the bottom of the gate trench structure; and
a second titanium nitride layer disposed on, and in direct
physical contact with the barrier layer, the second titanium
nitride layer being deposited over substantially an entirety of
the hafnium carbide barrier layer on the walls and the bottom of
the gate trench structure.
2
Appeal 2018-001014
Application 13/782,106
Appellant does not present separate arguments specifically directed to
the dependent claims under rejection (see App. Br. unnumbered 5-12).
Therefore, the dependent claims will stand or fall with their parent
independent claims of which claim 1 is representative.
We will sustain the Examiner's rejections for the reasons given in the
Final Office Action, the Answer, and below.
The Examiner finds that Jiang discloses a semiconductor structure
comprising an unoxidized titanium nitride layer having a tantalum carbide
layer thereon and concludes that it would have been obvious to replace the
tantalum carbide layer with a hafnium carbide layer as required by claim 1 in
view of Brown (Final Action 3-5).
Appellant does not dispute the Examiner's finding and conclusion
involving replacement of Jiang's tantalum carbide layer with Brown's
hafnium carbide layer (see generally App. Br.). Rather, Appellant contests
the Examiner's finding that Jiang's titanium nitride layer is unoxidized by
arguing "Jiang fails to teach or suggest forming its device such that titanium
nitride barrier layer 105/505 avoids oxidation" (id. at unnumbered 7
(underlining, bolding, and italics removed)). Further regarding this
argument, Appellant emphasizes that the Specification discloses titanium
nitride is prone to oxidation and correspondingly contends that Jiang's
titanium nitride would be in an oxidized form (i.e., titanium oxide) (id. at
unnumbered 8). 2
2 Appellant does not identify the time required for such oxidation. As a
consequence, the record before us is silent as to whether titanium nitride
would become oxidized in seconds or in years upon being exposed to
oxygen.
3
Appeal 2018-001014
Application 13/782,106
In response, the Examiner reinforces the finding that Jiang' s titanium
nitride layer is unoxidized by pointing out that Jiang's disclosed construction
of a tantalum carbide layer on a titanium nitride layer is the same
construction disclosed by Appellant as resulting in an unoxidized titanium
nitride layer (Ans. 7-8). In light of this circumstance, the Examiner finds
that "Jiang also teaches an unoxidized TiN layer" (id. at 8 ( citing Spec. ,r,r
29-30)).
Appellant replies by arguing "[a determination that] Jiang's titanium
nitride layer 105/505 is inherently unoxidized[] is simply wrong" and "Jiang
fails to inherently disclose that its barrier layer 105/505 is inherently
unoxidized" (Reply Br. unnumbered 4--5).
The deficiency of Appellant's argument is that it does not address, and
therefore does not show error in, the Examiner's reasoning that Jiang's
titanium nitride layer is unoxidized due to being covered by a tantalum
carbide layer which Appellant discloses will prevent titanium nitride
oxidation. In this regard, we emphasize that Appellant fails to advance any
reason why the Specification's construction of a titanium nitride layer
having a tantalum carbide layer thereon would result in unoxidized titanium
nitride but Jiang' s corresponding construction would not.
In summary, the record reflects that Jiang's titanium nitride layer
necessarily and inherently would be unoxidized due to being covered with a
tantalum carbide layer before modification or a hafnium carbide layer after
modification with Brown based on Appellant's disclosure that such a
construction of these material layers results in unoxidized titanium nitride.
4
Appeal 2018-001014
Application 13/782,106
We therefore sustain the Examiner's§ 103 rejections of the appealed
claims.
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).
AFFIRMED
5