Ex Parte Dennison et al

Patent Trial and Appeal Board

Mar 29, 2013

11447819 (P.T.A.B. Mar. 29, 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.
11/447,819 06/06/2006 Charles H. Dennison ITO.0622US (P23830) 3630
21906 7590 03/29/2013
TROP, PRUNER & HU, P.C.
1616 S. VOSS ROAD, SUITE 750
HOUSTON, TX 77057-2631
EXAMINER
BYRNE, HARRY W
ART UNIT PAPER NUMBER
2824
MAIL DATE DELIVERY MODE
03/29/2013 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 CHARLES H. DENNISON and JOHN M. PETERS
____________

Appeal 2011-000907
Application 11/447,819
Technology Center 2800
____________

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

Opinion for the Board filed by WHITEHEAD, Administrative Patent Judge.

Opinion Dissenting filed by FRAHM, Administrative Patent Judge.

WHITEHEAD, JR., Administrative Patent Judge.

DECISION ON APPEAL
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STATEMENT OF THE CASE
Appellants are appealing claims 1-3 and 5-14. Appeal Brief 5. We
have jurisdiction under 35 U.S.C. § 6(b) (2012).
We affirm.

Introduction
The invention is directed to a method of manufacturing a phase
change memory device. Specification 1.

Illustrative Claims (emphasis added)
1. A method comprising:

forming a planar heater layer over a select device of a phase change
memory; and

forming a phase change memory element over said select device.

9. A phase change memory comprising:

a select device;

a heater formed over said select device, said heater comprising a
planar layer;

and a phase change memory formed over said heater.

Rejection on Appeal
Claims 1-3 and 5-14 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over Karpov (U.S. Patent Application Publication Number
2006/0073631 A1; published April 6, 2006). Answer 4-7.
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Issue on Appeal
Does Karpov disclose a method of forming a planar heater layer over
a device of a phase change memory?

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.
The Examiner finds that Karpov discloses forming a planar heater
layer (44) within a phase change memory. Answer 4.
Appellants argue that:
The office action contends that the element 44 in
Karpov is a heater as claimed, when the cited reference to
Karpov insists that element 22a is the heater. See Karpov
at paragraph 33. Anyone skilled in the art, including
Karpov, knows that the heater is 22a and not 44. The
heater 22a is U-shaped, not planar, and, therefore, does not
meet the claimed limitations.

Appeal Brief 10.
We do not find Appellants’ arguments to be persuasive. It does not
matter if the reference refers to layer 22a as a heater; claim 1 does not
preclude the inclusion of multiple heaters. Karpov [0030]. Karpov’s layer
44 may be labeled as an electrode but it is formed from titanium silicon
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nitride the same as the Appellant’s heater layer. See Specification 5, lines
16-19. See also Karpov [0046]. Claim 1 does not indicate where the
heater is located in reference to the phase change element, all that claim 1
requires is that the planar heating layer and the phase change element be
formed over a non-descript select device of a phase change memory.
According to claim 1, the planar heating layer can be formed over the phase
change element or under the phase change element or directly besides the
phase change element. Therefore claim 1 is indistinguishable over the
Karpov because Karpov uses the same material as Appellants’ heater layer
to form a planar heater layer 44 and Karpov’s planar heater layer 44 is
formed within a phase change memory as spatially defined within claim 1.
See Karpov [0030]; Figure 10.
Claim 9 does not recite a phase change element as in claim 1. Claim
9 recites a phase change memory in the preamble wherein the phase change
memory comprises: a select device, a planar heater formed over the select
device and a phase change memory formed over the planar heater.1

1 We have decided the appeal before us. However, should there be further
prosecution of claim 9, which recites “[a] phase change memory comprising
. . . a phase change memory,” and claim 12, which recites “said phase
change memory element,” the Examiner’s attention is directed to 35 U.S.C.
§ 112, second paragraph, regarding indefiniteness. Regarding claim 9, it is
not clear how a phase change memory can include itself, as well as the
additional elements of “a select device” and “a heater” (claim 9 lines 2 and
3). Regarding claim 12, which depends from claim 9, the phrase “said phase
change memory element” lacks antecedent basis.
Due to the facts that (1) Appellants describe both the “phase change
memory element” of claim 1 (claim 1 line 3) and the “phase change
memory” of claim 9 (claim 9 line 4) as being element 30 in Figure 19 of the
Footnote continued on the next page.
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Claim 9 is not patentably distinguishable over Karpov’s invention
because claim 9 does not provide an indication of the spatial relation
between the heater and a phase change element, instead claim 9 recites a
phase change memory comprising of a phase change memory formed over a
heater layer. Therefore claim 9 only requires a phase change memory
wherein a planar heater is formed over a select device. As stated above, we
agree with the Examiner’s findings that Karpov discloses a phase change
memory wherein the planar heater is formed over a select device. See
Karpov [0030]; Figure 10.

Drawings (Appeal Brief 2, Summary of Claimed Subject Matter), (2)
Appellants’ Specification describes element 30 in Figure 19 as a
chalcogenide material that alters state or phase in response to voltage
potentials (Specification 11:9-25), and (3) the Examiner addresses the
“phase change memory” recited in line 3 of claim 9 as being a “phase
change memory element” (Answer 6 discussing claim 9; Ans. 9 last line
describing Karpov’s Figure 10 in relation to the “phase change memory
element” of claim 9), we understand both Appellants and the Examiner to
interpret the “phase change memory” of claim 9 (claim 9 line 3) as being the
phase change memory element or chalcogenide material 30 shown in
Appellants’ Figures 19-22.
Should there be further prosecution of claim 7, which recites “forming
a phase change memory element over the select device,” the Examiner’s
attention is directed to 35 U.S.C. § 112, fourth paragraph (“a claim in
dependent form shall contain a reference to a claim previously set forth and
then specify a further limitation of the subject matter claimed”), and Pfizer,
Inc. v. Ranbaxy Labs. Ltd., 457 F.3d 1284, 1292 (Fed. Cir. 2006). Because
claim 7 depends from claim 1, which recites “forming a phase change
memory element over said select device,” and claim 7 does not appear to
further limit claim 1.

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Consequently we sustain the Examiner’s obviousness rejection of
independent claims 1 and 9, as well as, dependent claims 2, 3, 5-8 and
10-14.

DECISION
The obviousness rejection of claims 1-3 and 5-14 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). See 37
C.F.R. § 41.50(f).

AFFIRMED

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FRAHM, Administrative Patent Judge, DISSENTING.

Appellants argue (App. Br. 10; Reply Br. 2-3) that the heater in
Karpov is element(s) 22/22a which is U-shaped and not planar as recited
in claims 1 and 9, and Karpov’s heater is not element 44 shown in Fig. 10
and described by Karpov as an “upper electrode” (see Karpov, para.
33). Because I agree with these arguments, and for the following reasons, I
respectfully dissent.
Claim 1 recites “a planar heater layer over a select device” and claim
9 recites “a heater formed over said select device.” In Karpov, select device
is 120 shown in Figure 10 (relied on by the Examiner at page 4 of the
Answer). Select device 120 includes L-shaped nitride layer 34, oxide layer
36, upper conductor 38, electrodes 40 and 44, and memory/switch material
42 which is switched on to operate the memory cell as known in the art
(compare Karpov ¶ [0033] with Ans. 8).
Karpov specifically names 22 and 22a as the heater/heater layer, and it
is U-shaped not planar. Although electrode 44 is made of the same material
as Appellants’ heater, titanium silicon nitride, it does not have the same
function of Appellants’ heater 20 shown in Figure 22, which is to heat the
phase change memory element 30. Thus, if Karpov intended upper electrode
44 or lower electrode 40 to be a heater and act as a heater to heat the phase
change memory element 32, Karpov would have expressly stated such since
Karpov states it expressly for heater 22/22a (see ¶ [0030]). In addition, the
heater layer in claims 1 and 9 is recited as being planar, not U-shaped. Thus,
an obvious statement is needed explaining why the change of the shape of
the heater layer would have been obvious to one of ordinary skill in the art at
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the time of Appellants’ claimed invention. The Examiner fails to provide
such an explanation, and as a result has failed to provide a prima facie case
of obviousness with respect to claims 1 and 9 on appeal.
In view of the foregoing facts and reasons, Appellants’ contention,
that Karpov’s element 44 is an upper electrode and not a heater, and that
Karpov’s U-shaped element(s) 22/22a is/are the heater, is persuasive. The
Examiner’s attempts to (i) call upper electrode 44 a heater to get around the
fact that heater 22 is U-shaped, and not planar, (ii) flip selected parts of
Karpov’s device upside down to meet the claims, and (iii) completely
modify and rearrange the form and function of Karpov’s Figure 10 (Ans.
8-12; see Figs. 10’ and 10” created and annotated by the Examiner), are not
adequate in making out a prima facie case of obviousness.
Because: (i) “[c]urrent flow between conductors 18 and 38 results in
electrical resistance heat developed by the heater 22a which heats the
material 32” (¶ [0034]); (ii) layer 22 acts “as a heater to change the phase of
an overlying phase change material [that] is U-shaped” (¶ [0030]); (iii)
“[p]rogramming of switching material 32 to alter the state or phase of the
material may be accomplished by applying voltage potentials to conductors
[18] and 38, thereby generating a voltage potential across select device 120
and memory element 130” (¶ [0038]); and (iv) Karpov’s memory elements
130 are activated by select devices 120 (Fig. 1; and ¶¶ [0015]-[0021]), one
of ordinary skill in the art would reach the following conclusions:
1 – upper electrode 44 cannot be a “planar heater layer” (claim 1) or a
“heater” (claim 9) because (i) lower conductor 18 activates the heater 22
which changes the phase of the switching material 32, (ii) electrodes 40 and
44 and switching material 42 operate to switch on the heater 22 through vias
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(not shown in Figs. 10/11 as per ¶ [0034]) connecting upper and lower
conductors 18 and 38 in a similar fashion as described by Appellants (Spec.
11:9-15:22; Fig. 22), and (iii) conductive materials 40 and 44 (the lower and
upper electrodes 40 and 44 shown in Fig. 10) are only discussed in
paragraphs [0033] and [0046] and are not described as creating heat to
change the phase of switching materials 32 or 42;
2 - the heater layer 22 cannot be said to be formed “over a select
device” as recited in claims 1 and 9 because heater 22 is under select device
120 (composed of L-shaped nitride layer 34, oxide layer 36, and upper
conductor 38); and
3 – phase change memory element 32 is not formed “over said select
device” (claim 1, Karpov’s select device 120) because phase change
memory element 32 is under select device 120.
To ascertain the scope and meaning of the claims, the Majority must
consider the claim language, the Specification, the prosecution history, and
relevant extrinsic evidence. Phillips v. AWH Corp., 415 F.3d 1303, 1314-17
(Fed. Cir. 2005) (en banc). “[A]bsent contravening evidence from the
specification or prosecution history, plain and unambiguous claim language
controls the construction analysis.” DSW, Inc. v. Shoe Pavilion, Inc., 537
F.3d 1342, 1347 (Fed. Cir. 2008).
In the instant case on appeal, the Majority ignores the plain language
of claims 1 and 9 requiring the select device be separate and distinct from
the heater, as well as Appellants’ Specification (see Spec. 11:9-15:22)
describing the function and operational limitations of the recited elements of
the phase change memory recited in claims 1 and 9.
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The Specification “is the single best guide to the meaning of a
disputed term,” Phillips v. AWH Corp., 415 F.3d at 1315, and may define a
term explicitly or by implication, Irdeto Access, Inc. v. Echostar Satellite
Corp., 383 F.3d 1295, 1300 (Fed. Cir. 2004). In the instant case on appeal,
the purpose and function of the recited “heater” and “select device” in a
phase change memory are different from each other (compare Spec. 11:9-
15:22 with Karpov’s ¶¶ [0016], [0020], and [0030]-[0038]). The
Specification defines the heater 20 as an element whose function it is to heat
the phase change material 30 and change its phase (Spec. 11:19-20).
Where a particular construction of an independent claim would nullify
claims that depend from it, the doctrine of claim differentiation creates a
presumption that such a construction is improper. See Liebel-Flarsheim Co.
v. Medrad, Inc., 358 F.3d 898, 910 (Fed. Cir. 2004). A construction of a
term which renders claims invalid or meaningless is only adopted when it is
the “only claim construction that is consistent with the claim’s language and
the written description.” Rhine v. Casio, Inc., 183 F.3d 1342, 1345 (Fed.
Cir. 1999) (emphasis added).
In the instant case on appeal, the Majority’s and Examiner’s
construction of independent claims 1 and 9 as having a planar heater which
is comprised of an electrode 40/44 of the select device 120 (see Op. 3-5;
Ans. 4-6) nullifies claims 2 and 10 which depend respectively from claims 1
and 9 because Karpov’s select device or ovonic switch operates as a switch
in the phase change memory and not as a heater to heat the phase change
memory material 32 to change its phase (see Ans. 5 and 7 where the
Examiner relies upon Karpov’s ¶ [0020] as disclosing an ovonic switch as
the select device). See Liebel-Flarsheim Co. 358 F.3d at 910.
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Furthermore, the Majority’s and Examiner’s construction of “heater”
as being an electrode that provides resistive heat, and thus renders claims 1
and 9 reciting a select device and a heater as different elements with
different functions as meaningless, is not the only claim construction
consistent with the language of claims 1 and 9 and Appellants’ Specification
(see Spec. 11:9-14:23) and Drawings (see Fig. 19-22), as discussed at length
infra. See Rhine v. Casio, Inc., 183 F.3d at 1345.
For reasons that follow, and based on the individual functions
attributed by Appellants’ Specification (Spec. 11:9-15:22) to the various
elements recited in claims 1 and 9, neither Karpov’s upper electrode 44, nor
Karpov’s lower electrode 40 (which are both part of the select device 120
shown in Figure 10) can be reasonably interpreted as the recited planar
heater layer (claim 1), or the heater comprising a planar layer (claim 9)
which are each formed “over” a “select device” (claims 1 and 9).
Appellants’ Specification (Spec. 11:9-15:22) describing Figure 22
explains how the phase change memory cell works. Certain components are
key to the operation of the device. Namely, the select device (made up of
lower electrode 14, switch material 16, and upper electrode 18) is used to
switch on the heater 20 to heat the phase change material 30 to change the
memory from one state to another. Karpov’s device works the same
way. The important aspect of this is that the phase change memory material
30 (Karpov’s material 32) is not the same as the switch material 16
(Karpov’s 42). Notably, page 14 lines 18-20 of Appellants’ Specification
explains just this, that material 30 changes phase, but material 42 does not.
While it may be possible that a phase change memory could perform
the same function whether a heater is above or below a phase change
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memory element with no change in the operational principle, the physical
arrangement recited in each of claims 1 and 9 necessitates that certain
operational principles apply and correspond to individual ones of the (i)
“planar heater layer” (claim 1) or heater comprising a planar layer” (claim
9), (ii) “select device” (claims 1 and 9) which can be an “ovonic threshold
switch” (claim 2), and (iii) “phase change memory element” (claim 1) or
“phase change memory formed over said heater” (claim 9)2. See Phillips v.
AWH Corp., 415 F.3d at 1314-17.
However, claims 1 and 9, even broadly interpreted, (i) require a planar
heater or heater layer be formed “over” a select device or switch; (ii) require
a phase change memory element be formed “over” the select device (claim
1) or the heater (claim 9); and (iii) the plain language of claims 1 and 9,
enlightened by the description of the function of the phase change memory
in Appellants’ Specification (Spec. 11:9-14:23, describing the function of
the chalcogenide material or phase change memory element 30, the select
device 120, and the heater), requires the heater or heater layer to be a
separate and distinct element from the select device of the phase change
memory.
Thus, the Majority’s interpretation (see Op. 3-4) of Karpov’s upper
electrode 44, which is part of Karpov’s select device 120 shown in Figure 10
which comprises L-shaped nitride layer 34, oxide layer 36, conductor 38,

2 I concur with the Majority’s understanding that both Appellants and the
Examiner interpret the “phase change memory” recited in line 4 of claim 9,
and I consider the recitation as harmless error in light of the Specification’s
clear description of element 30 as being a phase change memory element
such as chalcogenide. See supra fn. 1 Op. 4-5.
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memory material 42, and electrodes 40/44 (see Karpov, ¶ [0033]; Ans. 8), as
being the heater or heater layer recited in claims 1 and 9 on appeal, is
incongruent with the requirement that the select device and heater be
separate and distinct elements. Furthermore, neither the Majority (see supra
Op. 3-4) nor the Examiner provide any explanation as to how the upper
electrode 44 (see Ans. 4, where the Examiner relies on the upper electrode
44 as the planar heater layer recited in claim 1) and/or lower electrode 40
(see Ans. 6, where the Examiner relies upon the lower electrode 40 as the
heater recited in claim 9) could act as a heater and a select device at the
same time. In fact, the Majority (see supra Op. 4-5) fails to address either
(i) how Karpov’s select device 120 can be separate and distinct from the
electrodes 40/44 relied upon by the Examiner as the heater or heater layer
recited in claims 1 and 9, when the heater layer is described in plain
language in claims 1 and 9 as being planar and being under the select
device,3 or (ii) the Examiner’s reliance upon lower electrode 40 as the heater
recited in claim 9.
In this light, the argument presented by the Majority that the claimed
structure could have multiple heaters, the upper electrode 44 of the select
device 120 being one of them, ignores the operation of the phase change
memory and the function it performs based on the individual and underlying
functionalities of the (i) heater or heater layer, (ii) select device, and (iii)
phase change memory element. See In re Gal, 980 F.2d 717 (Fed. Cir.

3 Notably, the Majority and Examiner fail to explain, how Karpov’s
electrodes 40/44 can be “over” the select device 120 when the electrodes
40/44 are part of the select device itself (see Karpov, ¶ [0033]; Ans. 8).
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1992) (reversing the Board because the Federal Circuit was not persuaded by
the Commissioner’s argument that differences in the arrangement and
position of layers of functional circuit make no difference in the operation of
the functional circuit because such an argument ignores the claimed
structure and the functions each element performs, as well as the differences
in structure of the chip).
Due to (i) the impossibility that either of the electrodes (40 or 44) of
the select device or switch 120 could act as a heater to change the phase of
material 30 (because the electrodes 44 and 40 serve to operate the switch
using material 42 which is not capable of changing phases as described by
Appellants in the Specification at page 14, lines 18-24), and (ii) the fact that
Karpov’s U-shaped heater or heater layer 22 is described by Karpov as
“act[ing] as a heater to change the phase of an overlying phase change
material” (¶ [0030]) and Karpov’s select device 120 is described as being a
“switch” (¶ [0020]), one of ordinary skill in the art at the time of Appellants’
claimed invention would not reasonably find any teaching, suggestion, or
motivation to modify Karpov’s phase change memory structure (Fig. 10) as
articulated by the Examiner (Ans. 4-12), in order to produce the phase
change memory structure recited in Appellants’ claims 1 and 9 and shown in
Appellants’ Figure 22.
In view of the foregoing reasons, I respectfully dissent from the
Majority’s Opinion, and I would reverse the Examiner’s rejection of
independent claims 1 and 9, as well as claims 2, 3, and 5-14 depending
respectively therefrom.

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