Ex Parte PAL et al

Patent Trial and Appeal Board

Feb 20, 2014

12209056 (P.T.A.B. Feb. 20, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte ROHIT PAL, DAVID BROWN,
and SCOTT LUNING
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Appeal 2011-013341
Application 12/209,056
Technology Center 2800
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Before BRADLEY R. GARRIS, PETER F. KRATZ, and
BEVERLY A. FRANKLIN, Administrative Patent Judges.

GARRIS, Administrative Patent Judge.

DECISION ON APPEAL

Appellants appeal under 35 U.S.C. § 134 from the Examiner's
decision rejecting all pending claims 1, 3-11, 13-18, and 20. We have
jurisdiction under 35 U.S.C. § 6.

We REVERSE.
Appeal 2011-013341
Application 12/209,056

2
Appellants claim a method of fabricating a semiconductor device
structure (independent claims 1 and 11) and an isolation arrangement for a
semiconductor device structure (remaining independent claim 18) wherein
the composition of an upper layer of isolation material is the same as the
composition of a lower layer of isolation material.
A copy of representative claim 1, taken from the Claims Appendix of
the Appeal Brief, appears below.
1. A method of fabricating a semiconductor device
structure, the method comprising:
providing a substrate having a layer of semiconductor
material, a pad oxide layer overlying the layer of semiconductor
material, and a pad nitride layer overlying the pad oxide layer;
selectively removing a portion of the pad nitride layer, a
portion of the pad oxide layer, and a portion of the layer of
semiconductor material to form an isolation trench;
depositing a lower layer of isolation material in the
isolation trench such that the lower layer of isolation material
only partially fills the isolation trench;
thereafter forming a layer of etch stop material overlying
the lower layer of isolation material; and
thereafter forming an upper layer of isolation material
overlying the layer of etch stop material such that the layer of
etch stop material is located between the lower layer of
isolation material and the upper layer of isolation material, the
composition of the upper layer of isolation material being the
same as the composition of the lower layer of isolation material.
Appeal 2011-013341
Application 12/209,056

3
According to the Examiner, claims "1-7, 11-15, 18, and 20 [sic, 1, 3-7,
11, and 13-15]" (Ans. 3) are rejected under 35 U.S.C. § 102(b) as anticipated
by Hong (US 2003/0013272 A1, pub. Jan. 16, 2003).1
The remaining pending claims 8-10, 16-18, and 20 are rejected by the
Examiner under 35 U.S.C. § 103(a) as unpatentable over Hong in view of
Han (US 2009/0039442 Al, pub. Feb. 12, 2009).
In each of the above rejections, the Examiner finds that Hong
discloses a method and an arrangement wherein "the composition of the
upper layer of isolation material being the same as the composition of the
lower layer of isolation material (Fig. 8 and [0035] and [0040])" (Ans. 4; see
also id. at 7).
Appellants convincingly argue that the Examiner's finding is
erroneous because Hong, in fact, teaches using two different compositions
for these layers in order to accommodate the high aspect ratio of the trench
in which they are located (App. Br. 10-11 citing Hong ¶¶ 35 and 40). In
response, the Examiner contends that Hong's disclosure of using two
different compositions is merely a preference and that Hong also discloses
the use of USG and HDP oxide for the lower layer as well as the upper layer
(Ans. 9-10). As more fully explained by Appellants in the Reply Brief, the
Examiner's contention is directly contradicted by the Hong reference (Reply
Br. 3-5) which expressly teaches "the trench 140 having an aspect ratio of 4

1 Notwithstanding Appellants' correct observation of an oversight (see,
e.g., App. Br. 9, n. 1), the Examiner improperly continues to include in this
rejection claims 2 and 12 which are no longer pending as well as claims 18
and 20 which are not discussed in the § 102 rejection and which are
acknowledged in the § 103 rejection to distinguish over Hong.
Appeal 2011-013341
Application 12/209,056

4
or higher cannot be filled with the HDP oxide or USG [i.e., as the lower
isolation layer 170]" (Hong, ll. 5-6 of ¶ 35; emphasis added).
For this reason alone, we will not sustain the § 102 and § 103
rejections advanced by the Examiner in this appeal.
The decision of the Examiner is reversed.

REVERSED

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