Infineon Technologies AG

Patent Trials and Appeals Board

Oct 26, 2020

2019006913 (P.T.A.B. Oct. 26, 2020)

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.
14/518,013 10/20/2014 Thoralf Kautzsch INFAP620US 5600
51092 7590 10/26/2020
Eschweiler & Potashnik, LLC.
Rosetta Center
629 Euclid Ave., Suite 1000
Cleveland, OH 44114
EXAMINER
MAI, ANH D
ART UNIT PAPER NUMBER
2829
NOTIFICATION DATE DELIVERY MODE
10/26/2020 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docketing@eschweilerlaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte THORALF KAUTZSCH
Appeal 2019-006913
Application 14/518,013
Technology Center 2800
Before ROMULO H. DELMENDO, JEFFREY B. ROBERTSON, and
N. WHITNEY WILSON, Administrative Patent Judges.
WILSON, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s August 16, 2018 final decision to reject claims 1, 3, 5, 9, 21, and
23 (“Final Act.”). Claims 2, 4, 6, 8, and 10–20 have been cancelled.
Claims 7 and 22 have been withdrawn. We have jurisdiction under
35 U.S.C. § 6(b).
We reverse.

1 We use the word Appellant to refer to “applicant” as defined in
37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as
Infineon Technologies AG (Appeal Br. 1).
Appeal 2019-006913
Application 14/518,013

2
CLAIMED SUBJECT MATTER
Appellant’s disclosure is directed to an electronic device based on a
single crystal semiconductor substrate (Abstract). In particular, the
disclosure is directed to a micro-electro-mechanical system (MEMS), which
combines electronic functionality with mechanical actions, and which can be
used, inter alia, for accelerometers or energy harvesters in which movement
of a suspended mass is converted into electrical energy (Spec. ¶ 2). The
claimed invention is an electronic device containing a cavity 110, which is
fully enclosed in a semiconductor substrate 100, as shown in FIG. 1 below:

Fig. 1 schematically illustrates an electronic device according to an
embodiment of the disclosure of the application on appeal.

A movably suspended mass 120, which is part of the semiconductor
substrate 100 is suspended in the cavity 100 (Spec. ¶¶ 5, 23). The claimed
structure may be more easily understood by reference to a portion of FIG. 8,
which is reproduced below with additional labeling of suspended mass 120
and cavity 110:

A portion of FIG. 8 from the application on appeal shows cavity
schematic view of the claimed structure.

Appeal 2019-006913
Application 14/518,013

3
The claimed device also contains a specific arrangement of electrodes.
Claim 1, reproduced below from the Claims Appendix, is illustrative of the
claimed subject matter:
1. An electronic device, comprising:
a single, unitary semiconductor substrate;
a cavity embedded within the single, unitary
semiconductor substrate, such that the single, unitary
semiconductor substrate surrounds each surface of the cavity;
a movably suspended mass defined in the single, unitary
semiconductor substrate by one or more trenches extending
from one side of the single, unitary semiconductor substrate to
the cavity;
a first electrode layer on the suspended mass; and
a cover layer covering the suspended mass and including
a second electrode layer arranged opposite to, and vertically
above, the first electrode layer and spaced therefrom by a gap,
wherein the first electrode layer includes a first set of
comb like first electrode fingers;
wherein the second electrode layer includes a second set
of comb like second electrode fingers,
wherein the first set of comb like electrode fingers
comprises a first subset of first electrode fingers connected to a
first voltage terminal and a second subset of first electrode
fingers connected to a second, different voltage terminal,
wherein the second set of comb like electrode fingers
comprises a first subset of second electrode fingers operable to
be charged according to a first polarity and a second subset of
second electrode fingers operable to be charged according to a
second polarity which is opposite to the first polarity, and
wherein the first electrode layer comprises recesses
separating electrode fingers of the first set of comb like
electrode fingers, and wherein the recesses extend into the
movable suspended mass.

Appeal 2019-006913
Application 14/518,013

4
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Renna et al. US 8,101,448 B2 January 24, 2012
Mabuchi et al. US 8,212,450 B2 July 3, 2012
Altena et al., “Design, Modeling, Fabrication and Characterization of an
Electret-Based MEMS Electrostatic Energy Harvester,” IEEE
Transducers 2011, pp. 739–42.

REJECTION
Claims 1, 3, 5, 9, 21, and 23 are rejected under 35 U.S.C. § 103 as
unpatentable over Altena, in view of Renna and Mabuchi.
DISCUSSION
The Examiner finds that Altena discloses each of the limitations of
claim 1, except that Altena does not disclose that its semiconductor substrate
is a unitary semiconductor substrate, or that the first and second electrode
fingers comprise first and second subsets of electrode fingers (Final Act. 3).
The Examiner further finds that Renna teaches an electronic device
comprising a single unitary semiconductor substrate 20, a cavity 30a or 30d
embedded with the single unitary semiconductor substrate so that it
surrounds each surface of the cavity, and a movably suspended mass 38a or
38d defined by one or more trenches, as shown in FIG. 26B:

Appeal 2019-006913
Application 14/518,013

5
Renna’s FIG. 26B shows a view of a portion of the semiconductor substrate
during its manufacture.

The Examiner determines that “it would have been obvious . . . to
form the movably suspended mass of Altena in the single, unitary
semiconductor substrate as taught by Renna for the same intended purpose
of forming the suspended mass within a semiconductor substrate” (Final
Act. 4). The Examiner further determines that the claimed electrode finger
structure would have been obvious in view of Mabuchi’s teachings (Final
Act. 5–6).
Appellant argues, inter alia, that the cited art does not teach or suggest
“a cavity embedded within a single unitary semiconductor substrate, such
that the single unitary semiconductor surrounds each surface of the cavity”
(Appeal Br. 5). In particular, Appellant argues that the claimed moveably
suspended mass corresponds to the part of the semiconductor substrate
which covers the cavity (Appeal Br. 5, citing Spec. ¶¶ 22, 23). Appellant
further argues that the tops of the cavities in Altena and Renna are not part
of the substrate and, therefore, neither reference teaches or suggests a single,
unitary semiconductor substrate that surrounds each surface of the cavity
(Appeal Br. 5–7).
With regard to Altena, Appellant argues that the top of the cavity is
defined by an electret layer, not the MEMS wafer, as shown in FIG. 1(b):

Appeal 2019-006913
Application 14/518,013

6
Altena’s FIG. 1(b) shows a schematic illustration of the design of its energy
harvester.

Appellant’s argument regarding Altena’s structure is supported by the
evidence, as shown above. The Examiner determines that the electret wafer
in combination with the MEM wafer forms a “single semiconductor
substrate” and, therefore, meets the terms of the claim (Ans. 4). However,
we agree with Appellant that, in light of the disclosure of the Specification –
which states that the movably suspended mass is a part of the semiconductor
substrate (Spec. ¶ 23) – the entire semiconductor substrate which surrounds
the cavity must be “unitary,” meaning that it comes from the same original
materials. This construction is consistent with the disclosure in the
Specification, as required when construing a claim term. In re ICON Health
& Fitness, Inc., 496 F.3d 1374, 1379 (Fed. Cir. 2007). In view of this
construction, Altena’s structure, in which the top of the cavity is bound by
the electret wafer while the bottom is bound by the MEM wafer, does not
meet the requirements of the claim.
With regard to the disclosure of Renna, Appellant argues that the top
of its cavity is defined by dielectric layer 52 and, therefore, the single,
unitary semiconductor substrate does not surround each surface of the cavity
(Appeal Br. 7). While this argument is persuasive with regards to whether
the combination of dielectric layer 52 and substrate 20 would constitute a
unitary, semiconductor substrate surrounding the cavity,2 the Examiner
specifically finds that suspended dielectric membrane 38 corresponds to the

2 A dielectric layer is not a semiconductor, and thus dielectric layer 52
cannot combine to form a unitary, semiconductor substrate which surrounds
each side of the cavity.
Appeal 2019-006913
Application 14/518,013

7
claimed movably suspended mass (Ans. 5–6). However, as explained by
Appellant, dielectric membrane 38 is completely oxidized and is, therefore,
an insulator, and not a semiconductor (Reply Br. 3, citing Renna 7:7–9).
Thus, Renna does not teach a cavity “embedded within [a] single, unitary
semiconductor substrate such that the single, unitary semiconductor
substrate surrounds each surface of the cavity” because the top of Renna’s
cavity 30 is an insulator, not a semiconductor.
The Examiner has the initial burden of establishing a prima facie case
of obviousness based on an inherent or explicit disclosure of the claimed
subject matter under 35 U.S.C. § 103. In re Oetiker, 977 F.2d 1443, 1445
(Fed. Cir. 1992) (“[T]he examiner bears the initial burden, on review of the
prior art or on any other ground, of presenting a prima facie case of
unpatentability.”). To establish a prima facie case of obviousness, the
Examiner must show that each and every limitation of the claim is described
or suggested by the prior art or would have been obvious based on the
knowledge of those of ordinary skill in the art. In re Fine, 837 F.2d 1071,
1074 (Fed. Cir. 1988). In this instance, the evidence of record does not
support the Examiner’s determination that the cited art would have rendered
obvious “a cavity embedded within the single, unitary semiconductor
substrate, such that the single, unitary semiconductor substrate surrounds
each surface of the cavity.” Accordingly, we do not sustain the rejection.
CONCLUSION
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 3, 5, 9,
21, 23
103 Altena, Renna,
Mabuchi
1, 3, 5, 9,
21, 23
Appeal 2019-006913
Application 14/518,013

8
REVERSED