Petersson, Sture et al.

Patent Trials and Appeals Board

Apr 22, 2020

13462060 - (D) (P.T.A.B. Apr. 22, 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.
13/462,060 05/02/2012 Sture Petersson 4019020-188295 5644
23570 7590 04/22/2020
PORTER WRIGHT MORRIS & ARTHUR, LLP
INTELLECTUAL PROPERTY GROUP
41 SOUTH HIGH STREET
29TH FLOOR
COLUMBUS, OH 43215
EXAMINER
LEE, SHUN K
ART UNIT PAPER NUMBER
2884
NOTIFICATION DATE DELIVERY MODE
04/22/2020 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):
ipdocket@porterwright.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte STURE PETERSSON, GÖRAN THUNGSTRÖM, STANISLAV
POSPISIL, TOMAS SLAVICEK, and DAVID KRAPOHL
Appeal 2019-003887
Application 13/462,060
Technology Center 2800
Before JEFFREY T. SMITH, LINDA M. GAUDETTE, and
MONTÉ T. SQUIRE, Administrative Patent Judges.
GAUDETTE, Administrative Patent Judge.
DECISION ON APPEAL1
The Appellant2 appeals under 35 U.S.C. § 134(a) from the Examiner’s
decision finally rejecting claims 1, 2, 5, 7–18, 20–25, 27, 31, and 32.3
We AFFIRM.

1 This Decision includes citations to the following documents: Specification
filed May 2, 2012 (“Spec.”); Final Office Action dated February 1, 2018
(“Final”); Appeal Brief filed January 18, 2019 (“Appeal Br.”); Examiner’s
Answer dated February 19, 2019 (“Ans.”); and Reply Brief filed April 19,
2019 (“Reply Br.”).
2 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. The Appellant identifies the real party in interest as the
inventors. Appeal Br. 1.
3 We have jurisdiction under 35 U.S.C. § 6(b).
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CLAIMED SUBJECT MATTER
Claim 1, reproduced below, is illustrative of the claimed subject
matter:
1. A neutron detector comprising:
a silicon-based semiconductor detector substrate having a
front side and a back side;
a first electrical contact present on said front side and
comprising an electrically conductive neutron converting layer,
wherein said neutron converting layer is made of titanium
diboride, has a thickness of from about 100 nm to about 1 μm,
and forms an ohmic contact with said silicon-based
semiconductor detector substrate; and
a second electrical contact present on said back side and
comprising an electrically conductive layer.
Appeal Br. 41, Claims Appendix.
REFERENCES
The Examiner relies on the following prior art as evidence of
unpatentability:

Name Reference Date
Dreifus US 5,382,808 Jan. 17, 1995
Lott US 5,726,453 Mar. 10, 1998
Lacy US 2005/0258373 A1 Nov. 24, 2005

Choi et al, Electrical Characteristics of TiB2 for ULSI Applications, IEEE
Transactions on Electron Devices, Vol. 39, no. 10 (October, 1992), pp.
2341–2345 (“Choi”).
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McGregor et al. Microstructured semiconductor neutron detectors, Nuclear
Instruments and Methods in Physics Research A, Vol. 608, no. 1 (June
2009), pp. 125-131.
Mireshghi et al. High Efficiency Neutron Sensitive Amorphous
Silicon Pixel Detectors, IEEE transactions on Nuclear Science, Vol. 41, no.
4 (August 1994), pp. 915-921.
Sato et al. Plasma CVD-Grown 10B-Enriched Boron Films for Si Neutron
Detectors, Japanese Journal of Applied Physics, Vol. 29, no. 11 (November
1990), pp. 2526-2530.

REJECTIONS
The Examiner maintains the following rejections under 35 U.S.C.
§ 103(a):
1. Claims 1, 2, 9–16, 20–23, 25, and 27 are rejected over Lott in
view of Choi.
2. Claim 5 is rejected over Lott in view of Choi and Lacy.
3. Claims 7 and 8 are rejected over Lott in view of Choi and
McGregor.
4. Claims 9–11, 17, 18, and 24 are rejected over Lott in view of
Choi and Mireshghi.
5. Claims 12 and 13 are rejected over Lott in view of Choi and
Dreifus.
6. Claims 31 and 32 are rejected under over Lott in view of Choi
and Sato.
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OPINION
As an initial matter, we note that the Appellant argues that the
Examiner improperly relies on references that were not cited in any rejection
statement. See Appeal Br. 12 (referencing the Examiner’s citation to Becker,
et al, US 2005/0208218, in the Final Office Action, page 21); Reply Br. 3
(referencing the Examiner’s citations (Ans. 4, 8) to Sun et al, Determination
of degradation constant of Li ion from 10B(n,ay)7Li reaction in various
media, Proceedings in Radiochemistry A Supplement to Radiochimica Acta,
Vol. 1, no. 1 (1 September 2011), pp. 317–322); Reply Br. 4–5 (referencing
the Examiner’s citations to Becker in the Answer, pages 4 and 7); cf. Reply
Br. 1 (arguing that in the Answer, page 3, footnote 1, the Examiner relies on
a dictionary definition but fails to provide the Appellant with a copy
thereof). Because we do not rely on these references in our Decision, we
need not determine whether the Examiner’s citations were improper.
We now turn to the merits of the appeal.
The Examiner rejected claims 1, 2, 9–16, 20–23, 25, and 27 as
unpatentable over Lott in view of Choi. Final 3; see above-listed ground of
rejection 1. Lott discloses a neutron detector comprising a silicon-based
substrate (P-type semiconductor layer 16 on one side and N-type
semiconductor layer 14 on the other side). Lott 3:47–60. Lott discloses that
“electrical contacts are made to the semiconductor active region 14, 16 by
means of the conductive substrate 12 and a thin conductive contact 18.” Lott
4:1–3. “The contact 18 preferably has a thickness of from about 0.075 to 1
micron, and is made of any suitable material such as gold, platinum,
aluminum, titanium or nickel.” Lott 4:7–10. Lott discloses that “neutron
detector 10 includes a neutron converter layer 22 which generates charged
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particles when the layer is impinged by neutrons. The neutron converter
layer may comprise a relatively thin film or coating, or may comprise a
doped region of the device.” Lott 4:21–25. Lott teaches that “[s]uitable
materials for the neutron converter layer 22 include Li-containing materials
such as LiF, Li2O and lithium metal, and B-containing materials such as
ZrB2, B4C, H3BO3 and elemental boron.” Lott 4:32–35. Lott discloses that
“neutron converter layer 22 may be deposited directly on the semiconductor
active region 14, 16[,] . . . . [and] used as an electrical contact in place of the
contact 18. For example, the contact 18 may be doped with Li to serve a dual
purpose as an electrical contact and a neutron converter layer.” Lott 4:39–45.
Citing to the above disclosure, the Examiner found that Lott discloses
the claim 1 invention except for “a first electrical contact present on said
front side and comprising an electrically conductive neutron converting
layer, wherein said neutron converting layer is made of titanium diboride”
(claim 1 (emphasis added)). Final 3–4. The Examiner found that “ohmic
contacts on silicon substrates are well known in the art,” and cited Choi for a
teaching that an ohmic contact comprising titanium diboride was a known,
conventional electrical contact. Id. at 4 (citing Choi 2341, right col.; 2344,
left col.). The Examiner determined that “it would have been obvious to one
having ordinary skill in the art at the time of the invention to provide a
known conventional electrical contact (e.g., an ohmic contact comprising
titanium boride) as the unspecified electrical contact of Lott.” Id. at 5.
The Appellant argues that although Lott mention’s boron-containing
materials and elemental boron for use in a neutron converting layer, Lott
does not disclose that these materials serve the dual purpose of acting as a
neutron converter layer and as an electrical contact. Appeal Br. 11. In
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support of this argument, the Appellant relies on the declaration testimony of
Dr. Sture Petersson (Declaration under 37 C.F.R. § 1.132, executed Dec. 13,
2017 (“Decl.”)), one of the named inventors. See Appeal Br. 11. Based on
Dr. Petersson’s description of his education and work experience, we find
that Dr. Petersson is an expert in the field of semiconductor technology and
neutron detection, and is qualified to testify as to the level of ordinary skill
in the art at the time of the invention. See Decl. ¶ 1.
Dr. Petersson testified that neither Lott nor Choi discloses that
“titanium diboride was known by those of ordinary skill in the art for use as
a neutron converter.” Decl. ¶ 4. Dr. Petersson testified that “none of the
boron-containing materials mentioned in Lott for use as the neutron
converter layer can be used to achieve a combined electrically conductive
contact and neutron converter functions [sic] with high efficiency.” Id. ¶ 3.
Dr. Petersson further testified that “Choi would have [led] one of ordinary
skill in the art away from the use of titanium diboride as an electrically
conducting layer.” Id. ¶ 4. Citing to disclosure in Todorović et al,
Thin Solid Films, 300:272-277 (1997) (cited in the June 19, 2017
Information Disclosure Statement) and Choi et al, Journal of Applied
Physics, 69(11):7853 (1991) (“Choi 1991”) (cited in the June 19, 2017
Information Disclosure Statement), Dr. Petersson testified that the ordinary
artisan would have understood that annealing at 1000 ⁰C would be necessary
to render a TiB2 film capable of forming an ohmic contact; however, the
ordinary artisan would have been dissuaded from annealing at a high
temperature because Choi discloses that this results in boron diffusion for
TiB2 into a silicon-based substrate and increased contact resistance. Id. ¶ 5.
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Having considered the Examiner’s and the Appellant’s respective
positions together with the record evidence, we agree with the Examiner that
a preponderance of the evidence weighs in favor of obviousness as to claim
1. See Ans. 5–11.
As found by the Examiner (see Ans. 3), Lott discloses that
[t]he neutron converter layer may comprise a relatively thin
film or coating, or may comprise a doped region of the device.
The composition of the neutron converter layer 22 is selected
such that upon impingement by neutrons, charged particles such
as 1H, 3H, 7Li and 4He ions are generated. Species capable of
generating such charged particles include 6Li, 10B, H, and 3He.
Lott 4:23–29. This disclosure supports the Examiner’s determination that
Lott suggests that boron-containing materials are suitable for use as the
neutron converter layer and that the ordinary artisan would have understood
that the boron-containing materials explicitly identified in Lott—ZrB2, B4C,
H3BO3 and elemental boron (Lott 4:34–35)—are merely exemplary. See
Ans. 7. We have considered Dr. Petersson’s testimony that “none of the
boron-containing materials mentioned in Lott for use as the neutron
converter layer can be used to achieve a combined electrically conductive
contact and neutron converter functions [sic] with high efficiency” (Decl. ¶
3). However, we do not find this testimony relevant to the issue of
obviousness because claim 1 does not require that the electrical contact, or
neutron converting layer, function with high efficiency. Cf. Ex parte Obiaya,
227 USPQ 58, 60 (BPAI 1985) (“The fact that appellant has recognized
another advantage which would flow naturally from following the
suggestion of the prior art cannot be the basis for patentability when the
difference would otherwise have been obvious.”); Spec. 8:1–2 (indicating
that TiB2 is merely a preferred material for the neutron converting layer).
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We also are unpersuaded by Dr. Petersson’s testimony that “Choi
would have lead [sic] one of ordinary skill in the art away from the use of
titanium diboride as an electrically conducting layer” (Decl. ¶ 4), because
neither Dr. Petersson nor the Appellant has addressed the Examiner’s
finding that the various drawbacks that Dr. Petersson identifies relate to the
properties of TiB2 deposited on n-type Si (Ans. 9). See, e.g., Reply Br. 5–8.
As found by the Examiner, Lott discloses that a neutron converter layer
deposited directly on p-type Si can be used as an electrical contact, and Choi
discloses the TiB2/p-Si Schottky diodes show ohmic characteristics. Ans. 9;
see Lott Fig. 1, 3:47–49, 4:39–41; Choi 2344, Conclusion. Thus, the
Examiner has identified teachings in the prior art as to which boron-
containing materials likely would “serve a dual purpose as an electrical
contact and a neutron converter layer” (Lott 4:39–45). See PharmaStem
Therapeutics, Inc. v. ViaCell, Inc., 491 F.3d 1342, 1364 (Fed Cir. 2007)
(explaining that an obviousness rejection predicated on selection of one or
more components from numerous possible choices may be appropriate if the
prior art provides direction as to which of many possible choices is likely to
be successful); see also Sud-Chemie, Inc. v. Multisorb Techs., Inc., 554 F.3d
1001, 1009 (Fed. Cir. 2009) (“[E]vidence of unexpected results and other
secondary considerations will not necessarily overcome a strong prima facie
showing of obviousness”); In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359,
1368 (Fed. Cir. 2004) (explaining that the Board is entitled to weigh
declarations expressing opinions as to fact and conclude that the lack of
factual corroboration warrants discounting the opinions expressed in the
declarations); In re Bulina, 362 F.2d 555, 559 (CCPA 1966) (“[A]n affidavit
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by an applicant or co-applicant as to the advantages of his invention is less
persuasive than one made by a disinterested person.”).
In sum, based on our consideration of the totality of the record before
us, having considered the prima facie case of obviousness along with
Appellant’s arguments and evidence, we conclude that the preponderance of
evidence weighs in favor of obviousness of the claimed subject matter
within the meaning of §103. See In re Oetiker, 977 F.2d 1443, 1445 (Fed.
Cir. 1992).
As to the first ground of rejection, the Appellant presents separate
arguments in support of patentability of the following claim groupings: (1)
claim 2; (2) claims 9–11; (3) claims 12–14; (3) claim 15; (4) claim 25; and
(5) claim 27. Appeal Br. 21–27. The Examiner has addressed these
arguments in the Answer (see Ans. 11–14), and identified disclosure in Lott
and Choi that support the Examiner’s conclusion of obviousness as to these
claims. See also Final 5–12. Accordingly, we sustain the rejection of claims
1, 2, 9–16, 20–23, 25, and 27 over Lott in view of Choi.
As to above-listed grounds of rejection 2–6, we have considered the
Appellant’s arguments, but find them unpersuasive of reversible error for the
reasons explained in detail by the Examiner. See Ans. 14–23; see also Final
13–20. Accordingly, we also sustain these grounds of rejection.
DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s)/Basis  Affirmed Reversed
1, 2, 9–16,
20–23, 25,
27
103(a) Lott, Choi 1, 2, 9–16,
20–23, 25,
27

5 103(a) Lott, Choi, Lacy 5
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Claims
Rejected
35 U.S.C. § Reference(s)/Basis  Affirmed Reversed
7, 8 103(a) Lott, Choi, McGregor 7, 8
9–11, 17,
18, 24
103(a) Lott, Choi, Mireshghi 9–11, 17,
18, 24

12, 13 103(a) Lott, Choi, Dreifus 12, 13
31, 32 103(a) Lott, Choi, Sato 31, 32
Overall
Outcome:
  1, 2, 5, 7–
18, 20–25,
27, 31, 32

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED