Ex Parte Hausner et al

Patent Trial and Appeal Board

Mar 3, 2016

10555713 (P.T.A.B. Mar. 3, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
10/555,713 10/20/2006
57449 7590 03/03/2016
SHEEHAN PHINNEY BASS & GREEN, PA
c/o PETER NIEVES
1000 ELM STREET
MANCHESTER, NH 03105-3701
FIRST NAMED INVENTOR
Martin Hausner
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
41067-6124 9725
EXAMINER
PHAM, THANH V
ART UNIT PAPER NUMBER
2899
MAILDATE DELIVERY MODE
03/03/2016 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 MARTIN HAUSNER, JURGEN SCHILZ,
FRED PLOTZ, and HERMANN KARAGOZOGLU
Appeal2014-001215
Application 10/555,713
Technology Center 2800
Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
JAMES C. HOUSEL, Administrative Patent Judges.
TIMM, Administrative Patent Judge.
DECISION ON APPEAL 1
1 In our opinion below, we refer to the Specification filed November 4, 2005
(Spec.), Final Office Action filed September 28, 2012 (Final), the Appeal
Brief filed July 8, 2013 (Appeal Br.), the Examiner's Answer filed
September 6, 2013 (Ans.), and the Reply Brief filed April 11, 2013 (Reply
Br.).
Appeal2014-001215
Application 10/555,713
STATEMENT OF CASE
Appellants2 appeal the Examiner's decision to reject claims 18, 20-29,
and 31-36. We have jurisdiction under 35 U.S.C. §§ 6(b) and 134(a).
We AFFIRM.
The claims are directed to a radiation sensor. The major difference
between the claimed sensor and the prior art sensor, as described in the
Specification, is in the shape of a cavity within the sensor frame, and the
angle of the cavity sidewall. Spec. 1.
Appellants depict the prior art sensor in Figure 11. The prior art
radiation sensor has a sensor element 114 mounted on a membrane 113 that
is stretched and fixed above a rectangular support frame of silicon 112.
Spec. 1-2; Fig. 11. The support frame 112 has a rectangular cavity 111. See
Figure 11, reproduced below:
Figure 11 is a schematic view of a prior art radiation sensor
2 Appellants identify the real party of interest as Excelitas Technologies
Singapore PTE LTD. Appeal Br. 1.
2
Appeal2014-001215
Application 10/555,713
Frame 111 includes a broadened bar where bonding pads 115a and
115b are typically located. Spec. 1. Locating the bonding pads 115a and
115b on the broadened bar allows one to bond contacts 115 without
damaging the membrane 113. Id.
The Specification describes a disadvantage to the prior art
construction. Spec. 1-2. The comers of the cavity 112 cause distortions and
creases in the membrane. Id. at 2. Also, the broadened bar makes the sensor
relatively large. Id. According to the Specification, "[t]ypically the
dimensions of the sensor elements include edge lengths of a few millimetres,
cavity diameters of 50 to 90 % of the edge lengths of the sensor elements
and membrane thicknesses of a few micrometers." Id. at 1.
Appellants seek to make a comparatively small and mechanically
stable radiation sensor. Spec. 4. Instead of a rectangular cavity, Appellants'
sensor has a circular or oval cavity. Figure 1, reproduced below, shows a
radiation sensor according to the claimed invention that has a circular cavity
2. Spec. 6-7.
6d 4h
(
Sb
6c
Figure 1 is a perspective view of the inventive radiation sensor
3
Appeal2014-001215
Application 10/555,713
The sensor has a support height H, support edge length L, cavity
diameter D, and a membrane thickness Das shown in Figure 2, reproduced
below:
4a Sh 3 jD
~d:s:::s:3~a£~~~~6:;:i;:s::;:::s:~~5~~: 1 : ::!::
I i
~--------\----~ _l"
2 D : i
····-·-----·---·---·----------------,
L
Figure 2 is a cross-sectional view of the sensor of Figure 1.
Appellants produce the sensor cavity by etching from the rear side,
particularly by dry etching such as by reactive ion etching (RIE) or deep RIE
(DRIE). Spec. 5 and 10. An inductively coupled plasma (ICP) may be used.
Spec. 5 and 11. The walls may be formed so they are substantially
orthogonal. Spec. 14. The angle may be in a range of 85° to 95°. Id.
Claim 18, with reference numerals from Figure 1 and key limitations
highlighted, is further illustrative:
18. A radiation sensor comprising:
a support [ 1] comprising silicon and/ or GaAs and/ or a
semiconductor material, the support having a square contour
and a support edge length L less than 2 mm;
a cavity [2, 2a] which may be a recess or a through hole
formed in one surface of the support, the cavity having a cavity
diameter D greater than 55% and less than 90% of the support
edge length L;
4
Appeal2014-001215
Application 10/555,713
a dielectric membrane [3] provided on the one surface of
the support;
a radiation sensor element [ 4a, 4b] formed above the
cavity and on the membrane;
electric terminals [ 5a, 5b] for the sensor element,
wherein:
the cavity in the surface of the support has a round
or oval contour [2a];
the side wall of the cavity is essentially orthogonal
to the support surface; the cavity is formed through dry
etching: and
an etching stop layer [108 in Fig. 9] is formed on
the one surface of the support between the one surface of
the support and the dielectric membrane.
Claims Appendix, Appeal Br. 15 (emphasis added).
Claim 36, the only other independent claim on appeal, is also directed
to a radiation sensor, but more narro\x1ly limits the support edge length to
less than 1.5 mm and the cavity diameter D to more than 65% and less than
80% of the support edge length. Claim 3 6 also introduces limitations on the
support height H (more than 50 µm and less than 1,500 µm) and membrane
thickness D (less than 3 µm and more than 0.1 µm).
The Examiner rejects claims 18, 20-29, and 31-36 under 35 U.S.C.
§ 103(a) as obvious over AAPA3 in combination with Schiller,4 Tomonari,5
Schieferdecker '0766 and/or Schieferdecker '787 .7 Final 2.
3 Applicants' Admitted Prior Art, Fig. 11 and Spec. 1-2.
4 Schiller et al., WO 01/00523 Al, published Jan. 4, 2001.
5 Tomonari et al., EP 0 599 364 A2, published June 1, 1994.
6 Schieferdecker et al., US 2003/0118076 Al, published June 26, 2003.
7 Schieferdecker et al., US 6,294,787 Bl, issued Sept. 25, 2001.
5
Appeal2014-001215
Application 10/555,713
Appellants focus their arguments on the rejection of claim 36. Appeal
Br. 7-13. Appellants point out that claim 18 has some limitations similar to
those of claim 36, and relies upon the reasons presented against the rejection
of claim 36, rather than present any further argument against the rejection of
claim 18. Appeal Br. 13. None of the rejections of the dependent claims are
argued separately. Id. We select claims 18 and 36 as representative.
OPINION
We first consider the issues relevant to both claims 18 and 36.
The first issue raised by Appellants is whether the Examiner has
reversibly erred in finding reasons within the prior art for forming the cavity
of the prior art (AAP A) with a round contour and essentially orthogonal
sidewalls as required by both claims 18 and 36. Appeal Br. 7-8; Reply Br.
3-5.
Appellants have not convinced us of a reversible error in the
Examiner's finding of reasons for making the combination.
As pointed out by the Examiner, Tomonari teaches a radiation sensor
that has a round cavity as shown in Figure 59. Fig. 59 at B. According to
Tomonari, rounding the comers of the cavity prevents the distortion and
damage to the membrane (thermally infrared absorbing film 13 (13P in Fig.
59)) that had been likely to occur at the comer portions. Tomonari, col. 15,
11. 45-57.
Appellants acknowledge that Tomonari discloses a device with a
substrate having a round cavity. Appeal Br. 8. But Appellants contend that
Tomonari's cavity sidewall is not essentially orthogonal to a support surface
as required by the claims. Id. The problem with this argument is that the
Examiner does not rely upon Tomonari for a teaching of essentially
6
Appeal2014-001215
Application 10/555,713
orthogonal sidewalls. And, in fact, the Examiner relies upon other evidence
supporting a finding that forming orthogonal support cavity sidewalls was
known in the art. Ans. 4, citing Schieferdecker '076 i-f 8.
Schieferdecker '076 describes that using reactive ion etching to create
a cavity in the support "yields a recess that is laterally fully defined by side
walls," and "at least one side wall (and in one embodiment, all of the side
walls) are arranged at an angle between 80 and 100° relative to the
membrane." Schieferdecker '076 i-f 8. According to Schieferdecker, "[s]uch
a sensor has high sensitivity and has particularly small dimensions." Id.
This is in comparison to the prior art sensors formed by, for instance, KOH
etching (the method used by Tomonari), that created the angle shown in
Schieferdecker's Figure 1. Schieferdecker '076 i-fi-13--4. Schieferdecker's
range of 80-100° suggests forming a 90° orthogonal sidewall as 90° is at the
center of the range. Schieferdecker '07 6 further suggests forming the
entirety of the sidewall or "all of the side walls" at the suggested angle.
Appellants have not convinced us of a reversible error in the
Examiner's finding of reasons to form a round cavity with an essentially
orthogonal sidewall in the support.
The next issue relevant to both claims 18 and 3 6 concerns the
dimensions of the support and cavity. The issue is whether the Examiner
reversibly erred in finding a suggestion within the prior art for forming the
support edge length L and cavity diameter D so the requirements of claims
18 and 3 6 are met.
Appellants contend that because the cited references would not have
led to modifying the AAP A sensor to have a round cavity with an essentially
orthogonal cavity side wall, it would not have been obvious for the radiation
sensor to have "'a support edge length L ... less than 1.5 mm;"' where "'the
7
Appeal2014-001215
Application 10/555,713
cavity diameter D is more than 65% and less than 80% of the support edge
length L,"' as recited in claim 36. Appeal Br. 10. We note that claim 18 is
broader than claim 36, reciting Las less than 2 mm and Das more than 55%
and less than 90%.
According to Appellants, "without essentially orthogonal side walls, a
person of ordinary skill would have considered a support edge length of less
than 1.5 mm to be too short to simultaneously accommodate a large enough
hole to ensure good thermal isolation of the sensor element and a thick
enough cavity wall to provide adequate structural integrity to the radiation
sensor." Appeal Br. 10-11. Appellants do not point to any evidence
supporting this statement. Id.
T omonari, as pointed out by both the Examiner and Appellants,
describes an infrared detector 14G that is 2x2 mm in size. Ans. 6; Reply Br.
6. We agree with Appellants that in this embodiment, which is associated
with Tomonari's Figure 17, the support 12G would have an edge length
larger than 2 mm. Reply Br. 7. But Tomonari's Figure 17 embodiment has
a substantially square shaped cavity. Tomonari, col. 9, 11. 28-30. The
embodiment of Figure 59 has a round cavity. The round support eliminates
comers and is able to better prevent distortion and damage of the membrane.
Tomonari, col. 15, 11. 45-57. Moreover, as we pointed out above,
Schieferdecker '076 teaches forming a particularly small sensor with
orthogonal sidewalls. Schieferdecker '076 i-f 8. There is no convincing
evidence that the claimed dimensions would have been outside the workable
or optimal dimensions one of ordinary skill in the art would have arrived at
when constructing the sensor suggested by the combination of prior art,
particularly in view of the dimensions Appellants disclose for the support of
8
Appeal2014-001215
Application 10/555,713
AAP A. See Spec. 1 (edge length of a few millimeters and cavity diameter of
50 to 90% of the edge lengths).
This determination applies to claim 18 as well, which has broader
ranges. Claim 18 requires the support edge length L be less than 2 mm and
the cavity diameter D be more than 55% and less than 90% of the support
edge length.
There is an additional issue relevant only to claim 36: Whether the
Examiner reversibly erred in finding a suggestion within the prior art to form
the membrane at a thickness D of less than 3 µm. Appeal Br. 9-10. Claim
18 does not limit the thickness of the membrane.
Although the Specification states that the membranes of the Figure 11
prior art sensors have "membrane thicknesses of a few micrometers," Spec.
1-2, Appellants and the Examiner agree that "a person of ordinary skill
would have understood that a dielectric membrane of less than 3 µm thick in
the AAP A radiation sensor would be too susceptible to damage." Appeal
Br. 9; Ans. 5. However, the Examiner finds that eliminating the comers by
making the cavity round would allow the use of a thinner membrane given
that eliminating the comers reduces damage to the membrane. Ans. 5---6.
The Examiner further finds that Schieferdecker '787 suggests using
membranes thinner than 1 µm. Ans. 6, citing Schieferdecker '787, col. 6, 11.
35--49. The membrane may be formed and the material depression (see, e.g.,
cavity 33 in Schieferdecker '787, Fig. 3A) formed later. Id. In the
embodiment of Figure 3A, the cavity 33 can be formed by reactive ion
etching to give vertical (orthogonal walls) and has a diameter between 50
and 200 µm. Schieferdecker '787, col. 5, 11. 10-20.
We agree with the Examiner that the prior art suggests forming a
radiation sensor having dimensions within the claimed range.
9
Appeal2014-001215
Application 10/555,713
CONCLUSION
We sustain the Examiner's rejection.
DECISION
The Examiner's decision is affirmed.
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)(l).
AFFIRMED
10