Ex Parte Kammler et al

Board of Patent Appeals and Interferences

May 7, 2012

11550631 (B.P.A.I. May. 7, 2012)

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.
11/550,631 10/18/2006 Thorsten Kammler 2162.135700/DE0731 9005
10742 7590 05/08/2012
GLOBALFOUNDRIES INC.
c/o Williams, Morgan & Amerson
10333 Richmond , Suite 1100
Houston, TX 77042
EXAMINER
WITHERS, GRANT S
ART UNIT PAPER NUMBER
2895
MAIL DATE DELIVERY MODE
05/08/2012 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 BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________
Ex parte THORSTEN KAMMLER, PATRICK PRESS, ROLF
STEPHAN, and SVEN BEYER
____________________

Appeal 2010-002404
Application 11/550,631
Technology Center 2800
____________________

Before DENISE M. POTHIER, JEFFREY S. SMITH, and
JENNIFER S. BISK, Administrative Patent Judges.

BISK, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2010-002404
Application 11/550,631

2
SUMMARY
This is an appeal under 35 U.S.C. § 134 from the Examiner‟s rejection
of claims 1-9, 12-14, and 24-28. Claims 10, 11, and 15-23 have been
cancelled. We have jurisdiction under 35 U.S.C. § 6(b).
The Examiner made the following rejections:
Claims 1-6, 8, 9, 12-14, and 24-28 stand newly rejected under 35
U.S.C § 102 as anticipated by Samoilov (US 2005/0079692 A1; Apr. 14,
2005).
1

Claim 7 stands rejected under 35 U.S.C § 103(a) as unpatentable over
Samoilov and Liu (US 2006/0166457 A1; July 27, 2006).
We affirm.

STATEMENT OF THE CASE
Appellants‟ invention relates to the formation of silicided surfaces on
the source/drain regions of a field effect transistor. Representative claim 1,
reproduced below with key disputed terms emphasized, is illustrative of the
claimed subject matter:
1. A method, comprising:
forming a recess adjacent to a gate electrode of a
transistor;

1
In the Final Rejection, the Examiner rejected claims 1-6, 8, 9, 12-14, and
24-28 under § 103(a) as unpatentable over Samoilov. Final Rej. 2. In the
Answer, the Examiner made a new ground of rejection for these claims
under § 102 as anticipated by Samoilov. Ans. 3-6. Because the Examiner did
not repeat the § 103(a) rejection of these claims in the Answer, we assume
that rejection was withdrawn. Therefore, our analysis covers only the § 102
rejection.
Appeal 2010-002404
Application 11/550,631

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forming a semiconductor layer in said recess which
produces a tensile strain in the channel region of said
transistor;
forming a cap layer on said semiconductor layer; and
forming a silicided layer in an upper portion of said cap
layer and leaving a portion of said cap layer between said
silicided layer and said semiconductor layer unconverted to
silicide.

THE ANTICIPATION REJECTION
The Examiner finds that Samoilov anticipates claim 1. Ans. 3-4.
Appellants argue that Samoilov does not teach all the claimed features.
Specifically, Samoilov does not form each of the various layers in the
correct place, with the required characteristics. App. Br. 6-8; Reply Br. 2.

ISSUES
Has the Examiner erred in rejecting claim 1 by finding that Samoilov
discloses the claim limitations: (1) “forming a semiconductor layer in said
recess which produces a tensile strain in the channel region of said
transistor”; (2) “forming a cap layer on said semiconductor layer”; and
(3) “forming a silicided layer in an upper portion of said cap layer and
leaving a portion of said cap layer between said silicided layer and said
semiconductor layer unconverted to silicide”?

ANALYSIS
In the new ground of rejection of claim 1, the Examiner equates layer
132 in Figure 2B of Samoilov to the claimed “recess” and the “first layer of
Appeal 2010-002404
Application 11/550,631

4
the two part mulitlayer 140” in Figure 2C to the claimed “semiconductor
layer.” Ans. 4 (citing Samoilov ¶ [0030] (the “first SiGe layer”)). And,
according to the Examiner, the upper portion of layer 140, the “second SiGe
layer” along with layer 148 of Figure 2E are equivalent to the claimed “cap
layer.” Ans. 4 (citing Samoilov ¶¶ [0030]-[0031]).
Appellants argue that Samoilov does not teach that the top or upper
portion of layer 140 can be a “cap layer” as claimed because “[t]he upper
layer cannot be a cap layer over the stress inducing layer, when the upper
layer actually contributes more to the stress inducing nature of the layer 140
than the lower layer.” Reply Br. 2. We are not persuaded by Appellants‟
arguments.
First, Appellants do not assert that Samoilov only teaches an upper
layer which contributes more stress than the lower layer. See Reply Br. 2.
That is, Samoilov only discusses an example where the second layer has a
greater concentration of germanium than the first layer and does not state
that the multiple layers of layer 140 must vary in concentrations. See ¶ 0030.
Claim 1 does not exclude this situation, even if it were to occur, as long as
the semiconductor layer (e.g., lower layer 140) produces a tensile strain in
the transistor‟s channel region. Appellants do not point to a definition of
„cap layer‟ in the Specification that excludes the cap layer described by
Samoilov. Id.
Appellants also argue that layer 132 cannot be a recess. App. Br. 6-7.
Yet, Figure 2B in Samoilov discloses a recess 138 below element 134
(¶ [0029], ll. 9-10) where multi-layer 140 is located as shown in Figure 2C
and this layer produces a strain in the transistor‟s channel. Moreover,
Appeal 2010-002404
Application 11/550,631

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Appellants acknowledge that the “only layer formed in the recess is the
strain-inducing layer 140.” App. Br. 6 (emphasis omitted).
Finally, Appellants assert that layer 140 in Samoilov is not comprised
of different layers with the top portion being a cap portion. Reply Br. 2. Yet,
Appellants admit layer 140 can be composed of various sub-layers. See id.
The scope of claim 1 encompasses the cap layer being made of both the
upper layer of 140, which is unconverted to silicide, and the 148 layer as
found by the Examiner. Ans. 4.
Thus, we are not persuaded that the Examiner‟s rejection of claim 1 is
erroneous.
Appellants argue that claim 28 is patentable for the additional reason
that Samoilov does not disclose forming at least a portion of the cap layer in
the recess. App. Br. 7-8. However, as stated above, Appellants admit that
layer 140 is formed in the recess. App. Br. 6. Thus we are not persuaded that
the Examiner‟s rejection of claim 28 was erroneous.
Appellants do not separately argue claims 2-6, 8, 9, 12-14, and 24-27,
which depend from claim 1. App. Br. 8. Thus, we also sustain the
Examiner‟s rejection of these claims.

THE OBVIOUSNESS REJECTION
We also sustain the Examiner‟s obviousness rejection of claim 7
under 35 U.S.C. § 103(a) as obvious over Samoilov in view of Liu. Ans. 7-8.
Appellants rely on the same arguments presented for representative claim 1
to demonstrate that Samoilov and Liu collectively fail to teach all the
limitations of claim 7. App. Br. 8. As discussed above, we do not find these
arguments persuasive.
Appeal 2010-002404
Application 11/550,631

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DECISION
The Examiner‟s decision rejecting claims 1-9, 12-14, and 24-28 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)(iv).

AFFIRMED

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