Ex Parte Bez et al

Board of Patent Appeals and Interferences

Aug 31, 2010

11045170 (B.P.A.I. Aug. 31, 2010)

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.
11/045,170 01/27/2005 Roberto Bez 8410.P00014XD 3122
76225 7590 08/31/2010
Gerbera/BSTZ
Blakely Sokoloff Taylor & Zafman LLP
1279 OAKMEAD PARKWAY
SUNNYVALE, CA 94085
EXAMINER
GOODWIN, DAVID J
ART UNIT PAPER NUMBER
2818
MAIL DATE DELIVERY MODE
08/31/2010 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 ROBERTO BEZ, FABIO PELLIZZER,
MARINA TOSI, and ROMINA ZONCA
_____________

Appeal 2009-007440
Application 11/045,170
Technology Center 2800
____________

Before KENNETH W. HAIRSTON, ELENI MANTIS MERCADER,
and CARL W. WHITEHEAD, Jr., Administrative Patent Judges.

MANTIS MERCADER, Administrative Patent Judge.

DECISION ON APPEAL1

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or for filing a request for rehearing,
as recited in 37 C.F.R. § 41.52, begins to run from the “MAIL DATE”
(paper delivery mode) or the “NOTIFICATION DATE” (electronic delivery
mode) shown on the PTOL-90A cover letter attached to this decision.
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Application 11/045,170

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STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Final Rejection
of claims 1-32. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm-in-part.

INVENTION
Appellants’ Figures 23 and 22 are reproduced below:

Figure 23 depicts a phase change memory cell including a resistive
element 22, a memory region 38, spacer portions 55a, and a contact area 58
between the resistive element and the memory region (Spec. 11:21-29).
Figure 22 is a plan view of the phase change memory cell wherein the
strip 57 which is filled with the memory material filling memory region 38
forms a contact area 58 for each cell (see Spec. 11:16-20).
Appellants’ claimed invention is directed to a process for
manufacturing a phase change memory cell including a resistive element 22
and a memory region 38 of a phase changing material. Forming the memory
region 38 includes forming spacer portions 55a in direct contact with the
resistive element 22. Contact area 58 provides direct contact between the
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resistive element 22 and memory region 38. See Spec. 11:16-29; Figs. 22,
23.
Claim 1, reproduced below, is representative of the subject matter on
appeal:
1. A process for manufacturing a phase change memory cell,
comprising:
forming a resistive element including a first thin portion having a first
sublithographic dimension in a first direction; and
forming a memory region of a phase change material and including a
second thin portion having a second sublithographic dimension in a second
direction transverse to said first direction;
said first and second thin portions directly contacting one another and
defining a contact area of sublithographic extensions in the first and second
directions;
wherein said step of forming the memory region includes forming a
mold layer on top of said resistive element; forming a first lithographic
opening in said mold layer; forming spacer portions in said first lithographic
opening, said spacer portions being in direct contact with the first thin
portion of the resistive element and defining a slit having said second
sublithographic dimension; and depositing a phase change layer inside said
slit.

THE REJECTION
The Examiner relies upon the following as evidence of unpatentability:
Lai US 6,512,241 B1 Jan. 28, 2003
Maimon US 6,613,604 B2 Sep. 2, 2003
Maimon US 6,733,956 B2 May 11, 2004
The following rejections are before us for review:
1. The Examiner rejected claims 1-8, 11-18, 21-27, and 29-32 under 35
U.S.C. § 103(a) as being unpatentable over Maimon ‘956 in view of
Maimon ‘604.
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2. The Examiner rejected claims 9, 10, 19, 20, and 28 under 35 U.S.C. §
103(a) as being unpatentable over Maimon ‘956 in view of Maimon
‘604 and further in view of Lai.

ISSUES
The pivotal issues are:
1. whether the combination of Maimon ‘956 in view of Maimon ‘604
teaches “spacer portions being in direct contact with the first thin portion of
the resistive element” as recited in representative claim 1; and
2. whether the combination of Maimon ‘956 in view of Maimon ‘604
and Lai teaches a common memory region in direct contact with the resistive
elements of two adjacent memory cells as recited in independent claims 11
and 29.

FINDINGS OF FACT (FF)
The following Findings of Fact are supported by a preponderance of
the evidence:
1. Maimon ‘956 teaches a dielectric layer 150 (col. 6, l. 12) and Maimon
‘604 teaches a dielectric layer 160 (col. 6, ll. 15-18).
2. Maimon ‘956 teaches forming an opening 200 being in dielectric layer
150 which is in direct contact with the resistive element 136 (i.e., top
edge of electrode 134) (Figs. 14, 16, 17, and 18; col. 6, ll. 61-65; and
col. 7, ll. 1-42).
3. Maimon ‘604 teaches forming sidewall spacers 184 on the sidewalls
of the dielectric layer 160 (Fig. 12).
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4. Maimon ‘956 teaches a sublithographic width of the opening 200
being less than 500 Angstroms, and more preferably, less than 300
Angstroms (col. 7, ll. 1-6).
5. Maimon ‘604 teaches that the spacers 184 can be used to size the
smaller central opening 174 to be as small as 100 Angstroms (col. 6,
ll. 25-40).
6. Appellants’ Specification describes Figure 22 as two memory cells
each having a cup-shaped region 22 and connecting strip 57 filled
with the memory material forming the common memory region
between two cells (see generally Spec. 11:9-29; see also Fig. 19 with
equivalent cells 5 (i.e., C and D in the Y direction), Fig. 22).
7. Maimon ‘956’s Figures 17 and 18 show a single memory device
having two areas of contact A1 and A2 between the memory material
and the bottom electrode (col. 7, ll. 20-39).
8. Maimon ‘956 teaches first and second resistive elements (Fig. 18,
elements A1, A2) of a single memory cell.
9. Maimon ‘956 teaches that the memory cells are isolated from other
memory cells in the array by the addition of embedded field oxide
regions between each memory cell (col. 4, ll. 47-56).

PRINCIPLES OF LAW
The test for obviousness is what the combined teachings of the
references would have suggested to the artisan. Accordingly, one can not
show nonobviousness by attacking references individually where the
rejection is based on a combination of references. In re Keller, 642 F.2d
413, 426 (CCPA 1981).
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“The test for obviousness is not whether the features of a secondary
reference may be bodily incorporated into the structure of the primary
reference . . . . Rather, the test is what the combined teachings of the
references would have suggested to those of ordinary skill in the art.” Id. at
425.
The claims, of course, do not stand alone. Rather, they
are part of “a fully integrated written instrument” consisting
principally of a specification that concludes with the claims.
For that reason, claims “must be read in view of the
specification, of which they are a part.” . . . [T]he specification
“is always highly relevant to the claim construction analysis.
Usually, it is dispositive; it is the single best guide to the
meaning of a disputed term.”
Phillips v. AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir. 2005) (citations
omitted).

ANALYSIS
Analysis with respect to claims 1-10 and 21-28.
Figure 13 of Maimon ‘956, Figure 12 of Maimon ‘604, Figure 14 of
Maimon ‘956, and Appellants’ hypothetical Figure of Maimon ‘604 (Br. 12)
are reproduced below:

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Figure 13 and Figure 14 (appearing below Figure 13) of Maimon ‘956
show the etching of opening 200 through the layer 150. Figure 12 of
Maimon ‘604 does not etch the layer 150. Appellants’ hypothetical Figure
of Maimon ‘604 shows that if one had extended the opening 174 of Maimon
‘604 through the layer 150 like Maimon ‘956 extended the opening 200,
spacers 184 would still not have contacted the conductive liner 134.
Appellants argue (Br. 13) that, as shown in Figure 14, Maimon ‘956
only removes a sublithographic trench 200 of the dielectric layer 150
without removing any of the layer 150 underlying the layers 162, 180.
Appellants argue (Br. 13) that nothing in either reference suggests removing
the entire dielectric layer 150 of Maimon ‘956 or the entire conductive layer
150 of Maimon ‘604. Appellants explain (Br. 13) that forming such a
sublithographic trench of the resistive layer 150 of Maimon ‘604 would not
cause the spacers 184 to directly contact the conductive liner 134.
Appellants note that no portion of the layers 162, 180 of Maimon ‘956
directly contacts the bottom electrode 134, so there is no reason to believe
that any portion of the spacers 184 of Maimon ‘604 would directly contact
the conductive liner 134 as required by representative claim 1. Appellants
assert (Br. 13) that the spacers 184 would protect the underlying portion of
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the resistive layer 150 from being etched by the anisotropic etch of Maimon
‘956 (as shown in the hypothetical Maimon ‘604 Figure). Appellants also
assert (Br. 13) that one skilled in the art would not have been motivated to
remove any portion of the layer 150 of Maimon ‘604 because the layer 150
appears to be essential to the structure of Maimon ‘604 because the resistive
layer 150 provides for increased physical separation of the resistive layer
150 and the pore 174 of memory material from the substrate 100 (col. 8, ll.
36-41).
Figure 17 of Maimon ‘956 and Figure 12 of Maimon ‘604 are
reproduced below:

While we agree with Appellants that nothing in either reference
suggests removing the entire dielectric layer 150 of Maimon ‘956 or the
entire conductive layer 150 of Maimon ‘604, the Examiner did not suggest
such a modification.
At the outset, we agree with the Examiner (Ans. 16) that the
comparable layers for the modification are not layers 150 in both references,
but rather, Maimon ‘956’s dielectric layer 150 as modified by Maimon
‘604’s dielectric layer 160 (FF 1). The Examiner (Ans. 3-4, 16) relied on
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Maimon ‘956’s opening 200 being formed in dielectric layer 150 which is in
direct contact with the resistive element 136 as shown in Figures 17 and 18
(FF 2). The Examiner (Ans. 3-4, 16) then relied on Maimon ‘604’s teaching
of forming sidewall spacers 184 on the sidewalls of the dielectric layer 160
(FF 3) for the purpose of making opening 174 smaller, to thereby make
Maimon ‘956’s opening 200 smaller by forming spacers 184 on the
sidewalls of the dielectric layer 150. We agree with the Examiner’s findings
of fact and the conclusion of obviousness, and thus, we are not persuaded by
Appellants’ argument.
Appellants (Br. 14) further argue that the Examiner has cited no
evidence that forming the spacers 184 of Maimon ‘604 in the opening 200 of
Maimon ‘956, which is already sublithographic, was known, and that such a
modification would be extremely difficult. We are not persuaded by
Appellants’ argument.
While we agree that Maimon ‘956 teaches a sublithographic width of
the opening 200 being less than 500 Angstroms, and more preferably, less
than 300 Angstroms (FF 4), Maimon ‘604 teaches that the spacers 184 can
be used to size the smaller central opening 174 to be as small as 100
Angstroms (FF 5). Thus, clearly one skilled in the art would have been
motivated to use the Maimon ‘604’s spacers 184 in Maimon ‘956’s opening
200, because such a modification would yield the desired result of an
opening having a sublithographic limit of 100 Angstroms.
Accordingly, we are not persuaded by Appellants’ argument. We are
also not persuaded by the argument that the modification would be
extremely difficult because the test for obviousness is not whether the
features of a secondary reference may be bodily incorporated into the
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structure of the primary reference, but rather, the test is what the combined
teachings of those references would have suggested to those of ordinary skill
in the art. See Keller, 642 F.2d at 425.
Accordingly, we will affirm the Examiner’s rejection of claim 1, and
for similar reasons the rejections of claims 2-8 and 21-27. We note that
Appellants relied (Br. 17-18) on the same arguments raised for claim 1 for
claims 9, 10, and 28, which were rejected over the additional reference of
Lai. Thus, we will also affirm the Examiner’s rejection of claims 9, 10, and
28.
Analysis with respect to claims 11-20 and 29-32.
Appellants argue (Br. 15) that the Maimon patents show plural
memory cells (Figure 2A in both patents), but neither teaches or suggests a
common memory region in direct contact with the resistive elements of two
adjacent memory cells. We are persuaded by Appellants’ argument.
While we agree with the Examiner’s assertion that the common
memory region (200) contacts and is transverse to the first half memory cell
A1 and the second half memory cell A2 (Ans. 19), independent claims 11
and 29 do not recite half memory cells, but rather, “memory cells.” We turn
to Appellants’ Specification for the meaning of the term “memory cell”
because it is the single best guide to the meaning of a disputed term. See
Phillips, 415 F.3d at 1315.
Appellants’ Figure 22 is reproduced below:
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Appellants’ Figure 22 depicts resistive cup-shaped regions 22 of two
cells and connecting strip 57 filled with the memory material forming the
common memory region between two cells (see generally Spec. 11:9-29; see
also Fig. 19 with equivalent cells 5 (i.e., C and D in the Y direction)).
Appellants’ Specification describes Figure 22 as two memory cells
each having a cup-shaped region 22 and connecting strip 57 filled with the
memory material forming the common memory region between two cells
(FF 6). Maimon ‘956’s Figures 17 and 18 show a single memory device
(i.e., a single memory cell) having two areas of contact A1 and A2 between
the memory material and the bottom electrode (FF 7). Accordingly,
Maimon ‘956 neither teaches nor suggests “first and second resistive
elements of the first and second memory cells” as recited in representative
independent claim 11. At best, Maimon ‘956 teaches first and second
resistive elements (FF 8) of a single memory cell.
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We are also persuaded by Appellants’ arguments (Br. 17) that
Maimon ‘956 does not teach a common memory portion that contacts
respective resistive elements of respective cells, because if anything,
Maimon ‘956 teaches that the memory cells are isolated from other memory
cells in the array by the addition of embedded field oxide regions between
each memory cell (FF 9). We note that neither Maimon ‘604 nor Lai cures
the cited deficiencies.
For the above stated reasons, we will reverse the Examiner’s
rejections of independent claims 11 and 29 and dependent claims 12-20 and
30-32.

CONCLUSIONS
1. The combination of Maimon ‘956 in view of Maimon ‘604 teaches
“spacer portions being in direct contact with the first thin portion of the
resistive element”; and
2. the combination of Maimon ‘956 in view of Maimon ‘604 and Lai
does not teach a common memory region in direct contact with the resistive
elements of two adjacent memory cells.

ORDER
The decision of the Examiner to reject claims 1-10 and 21-28 is
affirmed. The decision of the Examiner to reject claims 11-20 and 29-32 is
reversed.
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)(v).

Appeal 2009-007440
Application 11/045,170

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AFFIRMED-IN-PART

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Gerbera/BSTZ
Blakely Sokoloff Taylor & Zafman LLP
1279 OAKMEAD PARKWAY
SUNNYVALE, CA 94085