Ex Parte Tsai et al

Patent Trial and Appeal Board

Apr 30, 2013

11754764 (P.T.A.B. Apr. 30, 2013)

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.
11/754,764 05/29/2007 Hui-Ying Tsai JCLA19564 7961
23900 7590 04/30/2013
J C PATENTS
4 VENTURE, SUITE 250
IRVINE, CA 92618
EXAMINER
PARKER, JOHN M
ART UNIT PAPER NUMBER
2823
MAIL DATE DELIVERY MODE
04/30/2013 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 HUI-YING TSAI and CHENG-MING YIH
____________

Appeal 2010-011786
Application 11/754,764
Technology Center 2800
____________

Before CARL W. WHITEHEAD, JR., ERIC S. FRAHM and
ANDREW J. DILLON, Administrative Patent Judges.

WHITEHEAD, JR., Administrative Patent Judge.

DECISION ON APPEAL
Appeal 2010-011786
Application 11/754,764

2
STATEMENT OF THE CASE
Appellants are appealing claims 1-23. Appeal Brief 1. We have
jurisdiction under 35 U.S.C. § 6(b) (2012).
We affirm.
Introduction
The invention is directed to a method for forming a shallow trench
isolation (STI) structure. Appeal Brief 1-2.

Illustrative Claim (Emphasis Added)
1. A method for forming a shallow trench isolation (STI)
structure, comprising:
forming a patterned mask layer on a substrate, the
patterned mask layer having a trench-like opening therein
exposing a portion of the substrate;
performing a first thermal oxidation process to the
substrate after the patterned mask layer is formed;
performing an anisotropic etching process with the
patterned mask layer as a mask to form a trench in the substrate,
after the first thermal oxidation process is performed; and
filling the trench with an insulating material.

Rejections on Appeal
Claims 1-10 stand rejected under 35 U.S.C. §103(a) as being
unpatentable over Wu (U.S. Patent Application Publication Number
2002/0115270 A1; published August 22, 2002) and Hsu (U.S. Patent
Appeal 2010-011786
Application 11/754,764

3
Application Publication Number 2003/0027402 A1; published February 6,
2003). Answer 3-6.
Claims 11-16 and 19-23 stand rejected under 35 U.S.C. §103(a) as
being unpatentable over Iguchi (U.S. Patent Number 6,551,925 B2; issued
April 22, 2003) and Hsu. Answer 6-9.
Claims 17 and 18 stand rejected under 35 U.S.C. §103(a) as being
unpatentable over Iguchi, Hsu and Cha (U.S. Patent Number 6,096,604;
issued August 1, 2000). Answer 10.
Issue on Appeal
Do Wu, Iguchi and Hsu, either alone or in combination, disclose
performing a “first thermal oxidation process to the substrate after the
patterned mask layer is formed” as recited in claims 1 and 11?

ANALYSIS
We have reviewed the Examiner’s rejections in light of Appellants’
arguments that the Examiner has erred. We disagree with Appellants’
conclusions. We concur with the findings and reasons set forth by the
Examiner in the action from which this appeal is taken and the reasons set
forth by the Examiner in the Answer in response to Appellants’ Appeal
Brief. However, we highlight and address specific findings and arguments
for emphasis as follows.
Appellants argue that it would be non-obvious to one of ordinary skill
in the art to combine Wu/Iguchi with Hsu in the manner in which the
Examiner proposes because Wu and Iguchi employs chemical vapor
deposition (CVD) to form a spacer precursor and Hsu teaches an in situ
steam generated (ISSG) process to form a trench liner. Appeal Brief 7.
Appeal 2010-011786
Application 11/754,764

4
Appellants further argue that the thickness of the Hsu’s oxide layer would be
counterproductive in the formation of an oxide layer “having a sufficiently
large thickness on the sidewalls on the patterned mask layer” of Wu/Iguchi.
We do not find Appellants’ arguments to be persuasive.
The Examiner finds that thermal oxidation (ISSG) is a well-known
alternative for oxide formation on a substrate, be it on a surface or in a
trench. Answer 11. We agree with the Examiner findings. Further, the
forming an oxide layer in either Wu’s or Iguchi’s trench is still considered to
be formed on the surface of the substrate since the substrate is exposed in the
trench as well. Also, the thickness of the oxide layer formed in Hsu is
irrelevant to the combinability of Hsu with Wu or Iguchi because one of
ordinary skill would simply adjust the thickness of the oxidation layer as
needed. “Common sense teaches, however, that familiar items may have
obvious uses beyond their primary purposes, and in many cases a person of
ordinary skill will be able to fit the teachings of multiple patents together
like pieces of a puzzle.” KSR Int’l v. Teleflex Inc., 550 U.S. 398, 420 (2007).
We sustain the Examiner obviousness rejections of claims 1 and 11, as
well as, dependent claims 2-10 and 12-23 not separately argued.

DECISION
The obviousness rejections of claims 1-23 are 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)(iv).

AFFIRMED
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