Ex Parte Pelella et al

Board of Patent Appeals and Interferences

Oct 29, 2008

10818155 (B.P.A.I. Oct. 29, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte MARIO M. PELELLA, DARIN A. CHAN, KEI-LEONG HO, and
LU YOU
____________

Appeal 2008-3840
Application 10/818,155
Technology Center 2800
____________

Decided: October 29, 2008
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Before CHARLES F. WARREN, CATHERINE Q. TIMM, and
ROMULO H. DELMENDO, Administrative Patent Judges.

DELMENDO, Administrative Patent Judge.
DECISION ON APPEAL
Statement of the Case
Appellants appeal under 35 U.S.C. § 134(a) from a final rejection of
claims 1-3, 6, and 7. (Appeal Brief filed March 5, 2007, hereinafter “Br.”;
Final Office Action entered October 5, 2006). Claim 5, the only other
pending claim, has been objected to, but indicated as allowable if rewritten
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in independent form. (Final Office Action at 4). We have jurisdiction under
35 U.S.C. § 6(b).
We AFFIRM.
Appellants’ invention relates to a “disposable spacer process for field
effect transistor fabrication.” (Spec. 3, ll. 2-3). According to Appellants, the
invention “provides disposable spacers that can be effectively removed
during field effect transistor fabrication without causing gouging.” (Id. 3, ll.
4-5).
Representative claim 1 reads as follows:
Claim 1: A method for forming a field effect transistor on a
substrate, said method comprising steps of:
forming extension regions in said substrate adjacent to a gate stack;
forming disposable spacers adjacent to said gate stack situated on
said substrate, said disposable spacers comprising amorphous carbon;
forming source and drain regions in said substrate, said source and
drain regions being situated adjacent to said disposable spacers;
removing said disposable spacers;
wherein said step of removing said disposable spacers causes
substantially no gouging in said substrate.
The prior art reference relied upon by the Examiner to reject the
claims on appeal is:
Brown 6,559,017 B1 May 6, 2003

The Examiner rejected the claims as follows: (i) claims 1, 2, 6, and 7
under 35 U.S.C. § 102(e) as anticipated by Brown; and (ii) claim 3 under 35
U.S.C. § 103(a) as unpatentable in view of Brown.
Appellants have relied upon the same argument for each of these
rejections, focusing on claim 1. Therefore, all appealed claims stand or fall
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in accordance with the outcome of this argument directed to claim 1. See 37
C.F.R. § 41.37(c)(1)(vii).
The Examiner found Brown discloses every limitation of claim 1.
(Ans. 3, l. 15 through 4, l. 4).
Appellants, on the other hand, argue that Brown does not disclose “the
forming of extension regions prior to removal of disposable spacers.” (Br. 8,
ll. 12-13).
The Examiner responds that “the language of claim 1 does not
inherently nor explicitly require that the extension regions be formed prior to
the amorphous carbon spacers.” (Ans. 6, ll. 17-18).

Issue
Thus, the issue arising from the contentions of the Examiner and
Appellants is whether the claim requires a specific step sequence of first
forming the extension regions and then forming the disposable spacers.
For the reasons expressed in the Answer and below, we hold that
claim 1 does not require a specific step sequence of first forming the
extension regions and then forming the disposable spacers.

Findings of Fact
1. Appellants’ Specification describes embodiments of forming a field
effect transistor on a substrate in which the extension regions are
formed before forming the disposable spacers. (Spec. 8, ll. 5-8; 12, ll.
5-6).
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2. The Specification also discloses an embodiment of forming a field
effect transistor on a substrate in which the extension regions are
formed after forming the disposable spacers. (Id. 14, ll. 4-6).
3. Brown discloses:
[A] method of disposable spacer utilization to avoid
spacer etch chemistry and active silicon gouging. The
method can include patterning a gate over a substrate,
forming amorphous carbon spacers adjacent lateral side
walls of the gate, forming source and drain regions in the
substrate at locations not covered by the amorphous
carbon spacer and the gate, removing the amorphous
carbon spacers, and forming extension regions in the
substrate at locations not covered by the gate. (Col. 2, ll.
45-55).

Principles Of Law
It is well settled that the United States Patent and Trademark Office
(PTO) is obligated to give claim terms their broadest reasonable
interpretation, taking into account any enlightenment by way of definitions
or otherwise found in the specification. In re Icon Health and Fitness, Inc.,
496 F.3d 1374, 1379 (Fed. Cir. 2007)(“[T]he PTO must give claims their
broadest reasonable construction consistent with the specification . . .
Therefore, we look to the specification to see if it provides a definition for
claim terms, but otherwise apply a broad interpretation.”); In re Bigio, 381
F.3d 1320, 1324 (Fed. Cir. 2004)(“[T]he PTO gives a disputed claim term its
broadest reasonable interpretation during patent prosecution.”).
This longstanding principle is based on the notion that “during patent
prosecution when claims can be amended, ambiguities should be recognized,
scope and breadth of language explored, and clarification imposed.” In re
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Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989). That is, a patent applicant has the
opportunity and responsibility to remove any ambiguity in claim term
meaning by amending the application. “Only in this way can uncertainties
of claim scope be removed, as much as possible, during the administrative
process.” In re Zletz, 893 F.2d at 322.
“To anticipate a claim, a prior art reference must disclose every
limitation of the claimed invention, either explicitly or inherently.” In re
Schreiber, 128 F.3d 1473, 1477 (Fed. Cir. 1997).

Analysis
Claim Interpretation
Appellants contend: “As specified by claim 1, the invention includes
forming disposable spacers adjacent to the gate stack situated on the
substrate following the formation of extension regions in the substrate
adjacent to the gate stack.” (Br. 4, ll. 14-16). According to Appellants, “the
disclosure in Brown fails to teach, disclose, or suggest the forming of
extension regions prior to removal of disposable spaces, and to use
disposable spacers for the purpose of preventing dopant loss from the
extension regions (since extension regions in Brown are formed after
disposable spacers have been already removed).” (Br. 8, ll. 12-15).
We do not agree. As recognized by the Examiner, claim 1 does not
specify any particular sequence for the steps of forming the extension
regions and forming the disposable spacers. (Ans. 7, ll. 3-4).
Moreover, the Specification indicates to one skilled in the relevant art
that the claimed invention broadly encompasses the prior art sequence. In
particular, the Specification discloses several embodiments, including an
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embodiment in which the extension regions are formed before forming the
disposable spacers and another embodiment in which the extension regions
are formed after forming the disposable spacers. (FF 1, 2). Appellants’
arguments ignore the actual scope of the claims and are therefore
unpersuasive. Claim 1 contains no language specifying an order or sequence
for the steps, and having read the Specification as a whole, one of ordinary
skill in the art would have understood the claimed subject matter to be broad
enough to encompass methods where the extension regions are formed
before or after the disposable spacers. In re Zletz, 893 F.2d at 321.

Anticipation Rejection of Claims 1, 2, 6, and 7 in View of Brown
As noted above, Appellants submit specific arguments addressing
claim 1, but do not separately argue dependent claims 2, 6, and 7.
Therefore, we confine our discussion to claim 1. See 37 C.F.R. §
41.37(c)(1)(vii).
Appellants’ argument that Brown does not disclose forming extension
regions before forming disposable spacers fails from the outset because the
claim is not so limited. As discussed above, the breadth of the claimed
subject matter encompasses methods where the extension regions are formed
before forming the disposable spacers as well as after forming the disposable
spacers. Therefore, as found by the Examiner, the claimed subject matter
encompasses Brown’s disclosed method of forming extension regions after
forming the disposable spacers. (Ans. 3, l. 15 through 4, l. 4; FF 3).
Appellants state:
[A] strong motivation for formation of the disposable
amorphous carbon spacers has been to prevent dopant loss from
the lightly doped extension regions. . . . In contrast, Brown is
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not directed to protection of extension regions from dopant loss,
since Brown requires formation of extension regions . . . after
removal of disposable spacers . . . (Br. 5, ll. 11-16).
Appellants’ statements focusing on the advantage of preventing
dopant loss do not have merit. As discussed above, the Examiner found
Brown discloses every limitation of claim 1. Thus, to the extent that Brown
does not achieve the advantage of preventing dopant loss, Appellants’
claimed method as broadly recited also fails to realize this advantage.
Therefore, Appellants have failed to show that the Examiner
reversibly erred in finding the claimed subject matter anticipated by Brown.

Obviousness Rejection of Claim 3 in View of Brown
Appellants rely on the same arguments as submitted with respect to
the anticipation rejection, as discussed above. (App. Br. 10). These
arguments are not persuasive to show that the Examiner reversibly erred in
determining that the claimed method, including a step of forming a silicide
layer on the substrate adjacent to the gate stack, would have been obvious to
one of ordinary skill in the art in view of Brown.

Conclusion of Law
Appellants have failed to show that the Examiner reversibly erred in
finding appealed claims 1, 2, 6, and 7 anticipated by Brown.
Appellants have also failed to show the Examiner reversibly erred in
concluding that one of ordinary skill in the art would have found the subject
matter of claim 3 obvious in view of Brown.

Order
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The decision of the Examiner rejecting claims 1-3, 6, and 7 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

MAT

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