Ex Parte HURWITT

Board of Patent Appeals and Interferences

Aug 21, 2003

08439490 (B.P.A.I. Aug. 21, 2003)

1
The opinion in support of the decision being entered today was
not written for publication and is not binding precedent of the
Board.
Paper No. 20
UNITED STATES PATENT AND TRADEMARK OFFICE
_______________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_______________
Ex parte STEVEN HURWITT
_______________
Appeal No. 2001-2455
Application No. 08/439,490
_______________
ON BRIEF
_______________
Before WARREN, WALTZ, and POTEATE, Administrative Patent Judges.
POTEATE, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the
examiner’s refusal to allow claims 1-41, which are all of the
claims pending in the application.
Appeal No. 2001-2455
Application 08/439,490
2
Claims 1, 14, 16, 26, 40 and 41 are representative of
the subject matter on appeal and are reproduced below:
1. A replaceable sputtering target comprising:
a circular target unit that is formed at least in
part of a volume of sputtering material, the unit having a
forward facing front sputtering face of the sputtering material
and a rearward facing rear face having a water impermeable
cooling surface lying in an annular area thereon around a center;
a recessed peripheral rim having:
a forward facing annular front edge having a
vacuum-sealing surface thereon surrounding the front
sputtering face, the front edge being spaced rearwardly
of the forward face of the target unit, and
a rearward facing annular rear edge having an
outer water-sealing surface thereon surrounding the
rear face of the target unit;
tension maintaining support structure fixed at the
center on the rear face, and
the rear face having an annular inner water-
sealing surface thereon surrounding the tension maintaining
support structure.

14. A removable sputtering target assembly comprising:
a replaceable target unit formed at least in part of a
volume of sputtering material, the unit having a forward facing
front sputtering face of the sputtering material and a rearward
facing rear face having a water impermeable cooling surface lying
in an area thereon;
the target unit having a forward facing front
peripheral edge having a vacuum-seal surface thereon surrounding
Appeal No. 2001-2455
Application 08/439,490
3
the front sputtering face and a rearward facing rear edge having
a water-seal surface thereon surrounding the rear face of the
unit; and
a cooling jacket connected to the back of the target
unit and having a forward facing peripheral edge having a water-
seal surface thereon in water sealing engagement with the water-
sealing surface on the rearward facing edge of the target unit so
as to enclose a cooling water cavity between the cooling jacket
and the cooling surface, the cooling jacket having cooling water
ports therein communicating with the cooling water cavity.
16. A sputtering cathode assembly comprising:
a housing;
a plasma shaping and confining magnet assembly carried
by the housing;
a target assembly removably connected to the housing,
the target assembly including:
a replaceable target unit having a back and formed
at least in part of a volume of sputtering material
having a front sputtering face thereon, and
a cooling jacket connected in water-sealing
relationship to the back of the target unit to enclose
a cooling water cavity between the cooling jacket and
the target unit, the cooling jacket having cooling
water ports therein communicating with the cooling
water cavity, the target unit having a rear face
positioned to be in direct cooling contact with flowing
cooling water within the cavity, the cooling jacket
configured to protectively isolate the magnet assembly
from cooling water in the cavity; and
a supply of flowing cooling water detachably
connectable to the cooling water ports upon the
removable connection of the target assembly to the
housing.
Appeal No. 2001-2455
Application 08/439,490
4
26. A sputtering apparatus comprising:
a vacuum chamber surrounded by a chamber wall and
having a substrate support mounted therein;
a sputtering cathode assembly mounted in an opening in
the chamber wall, the cathode assembly including a housing, a
plasma shaping and confining magnet assembly carried by the
housing, and a target assembly removably connected to the
housing;
the target assembly including:
a replaceable target unit having a back and formed
at least in part of a volume of sputtering material
having a front sputtering face thereon, and
a cooling jacket connected in water-sealing
relationship to the back of the target unit to enclose
a cooling water cavity between the cooling jacket and
the target unit, the target unit having a rear face
positioned to be in direct cooling contact with flowing
cooling water within the cavity, the cooling jacket
being removable with the target from the cathode
assembly;
an electrical insulator between the cathode assembly
and the chamber wall around the opening and surrounding the
sputtering face of the target; and
a power supply having a negative output connected to
the cathode assembly and a positive output connected at least
indirectly to the chamber wall.

40. A replaceable sputtering target for use in a
sputtering apparatus having a vacuum chamber surrounded by a
chamber wall and having a substrate support mounted therein, a
sputtering cathode assembly mounted in an opening in the chamber
wall, the cathode assembly including a housing, a plasma shaping
and confining magnet assembly carried by the housing, and a
Appeal No. 2001-2455
Application 08/439,490
1The version of claim 40 included in the Appendix to
appellant’s brief is incorrect. Claim 40 was originally added by
appellant’s amendment filed June 23, 1997, Paper No. 5.
Thereafter, an amendment after final rejection was filed December
5, 1997, Paper No. 7 in which appellant requested that the word
“back” in claim 40, line 26 be changed to “rear”. The examiner
indicated that this amendment would be entered upon the filing of
an appeal. See Advisory Action, Paper No. 8, mailed December 17,
1997. The amendment has not been made to claim 40 as the word
“back” could not be found. Thus, the current version of claim 40
is the claim as originally presented in Paper No. 5.
5
target assembly removably connected to the housing where the
target assembly includes a cooling jacket connected in water-
sealing relationship to the back of a target to enclose a cooling
water cavity between the cooling jacket and the target and
removable with the target from the cathode assembly, an
electrical insulator between the cathode assembly and the chamber
wall around the opening and surrounding the sputtering face of
the target; and a power supply having a negative output connected
to the cathode assembly and a positive output connected at least
indirectly to the chamber wall, the target comprising:
a circular target unit that is formed at least in part
of a volume of sputtering material, the unit having a forward
facing front sputtering face of the sputtering material and a
rearward facing rear face having a water impermeable cooling
surface lying in an annular area thereon around a center, the
rear face being configured to form a boundary of the cavity in
direct contact with cooling fluid in the cavity when the target
unit is connected to a cooling jacket;
a forward facing front edge having a vacuum-sealing
surface thereon bordering the front sputtering face to form a
vacuum seal when the target is connected in the apparatus; and
a rearward facing rear edge having a water-sealing
surface thereon bordering the rear face of the target unit to
seal the cavity when the target is connected to the cooling
jacket.1
Appeal No. 2001-2455
Application 08/439,490
6
41. A method of replacing a sputtering target in a
sputtering apparatus comprising the steps of:
disconnecting a used target from the cathode assembly
of the apparatus by removing the used target with a cooling
jacket containing a cooling fluid cavity attached to the back of
the target with the back face of the used target forming a
surface of the cavity;
then, separating the used target from the cooling
jacket, replacing the used target with a new target, connecting
the new target to the cooling jacket with the cooling fluid
cavity in contact with the back face of the new target;
then, connecting the new target to the cathode assembly
of the apparatus.
The references relied upon by the examiner are:
Urbanek et al. (Urbanek) 3,741,886 June 26, 1973
Landau 4,407,708 Oct. 4, 1983
Henderson et al. (Henderson) 5,240,580 Aug. 31, 1993
Demaray et al. (Demaray) 5,252,194 Oct. 12, 1993
Kerschbaumer 5,259,894 Dec. 14, 1993
Schuhmacher et al. (Schuhmacher) 5,421,978 June 6, 1995
(filed Dec. 28, 1993)
GROUNDS OF REJECTION
1. Claims 1-26 and 29-41 stand rejected under
35 U.S.C. § 103 as unpatentable over Landau in view of Urbanek
and Demaray.
2. Claims 1-26 and 29-41 stand rejected under
Appeal No. 2001-2455
Application 08/439,490
7
35 U.S.C. § 103 as unpatentable over Schuhmacher in view of
Urbanek or Demaray.
3. Claims 1-26 and 29-41 stand rejected under
35 U.S.C. § 103 as unpatentable over Kerschbaumer in view of
Urbanek and Demaray.
4. Claims 27 and 28 stand rejected under 35 U.S.C.
§ 103 as unpatentable over Landau in view of Urbanek, Demaray and
Henderson.
5. Claims 27 and 28 stand rejected under 35 U.S.C.
§ 103 as unpatentable over Schuhmacher in view of Urbanek,
Demaray and Henderson.
6. Claims 27 and 28 stand rejected under 35 U.S.C.
§ 103 as unpatentable over Kerschbaumer in view of Urbanek,
Demaray and Henderson.
We reverse as to all six grounds of rejection.
BACKGROUND
The invention relates to sputter coating for use in the
application of thin films to substrates in the manufacture of
semiconductor wafers. Appeal Brief, Paper No. 15, received
July 27, 1998, page 2. During a sputtering process, heat is
Appeal No. 2001-2455
Application 08/439,490
8
generated necessitating the cooling of the sputtering target.
Id., page 3. Cooling is usually accomplished by circulating
fluids to conduct heat from the target, the circulating fluids
usually being in thermal contact with the back of the target.
Id. “The present invention provides . . . [a] target assembly
that includes a replaceable target and a cooling jacket, with the
target assembly being removable from the cathode assembly of the
sputter coating machine with the target and cooling jacket still
assembled.” Id.

DISCUSSION
The initial burden of presenting a prima facie case of
obviousness rests on the examiner. In re Oetiker, 977 F.2d 1443,
1445, 24 USPQ2d 1443, 1444 (Fed. Cir. 1992). In order to
establish a prima facie case of obviousness, the examiner must
identify a suggestion or motivation to modify the teachings of
the cited references to achieve the claimed invention. In re
Kotzab, 217 F.3d 1365, 1370, 55 USPQ2d 1313, 1316-17 (Fed. Cir.
2000). “[A] rejection cannot be predicated on the mere
identification . . . of individual components of claimed
Appeal No. 2001-2455
Application 08/439,490
2Demaray teaches rotating magnetic means and is relied on
for a showing of moveable magnets recited in various dependent
claims. Examiner’s Answer, page 4.
9
limitations.” Ecolochem, Inc. v. Southern Cal. Edison Co.,
227 F.3d 1361, 1375, 56 USPQ2d 1065, 1076 (Fed. Cir. 2000)
(quoting Kotzab, 217 F.3d at 1371, 55 USPQ2d at 1317).
The examiner maintains that each of the primary
references, Landau, Schuhmacher and Kerschbaumer, disclose the
invention as claimed in claims 1-26 and 29-41 with the exception
that “direct cooling is not discussed and a tension supporting
structure in the center is not discussed.” Examiner’s Answer,
Paper No. 16, mailed October 8, 1998, page 4. The examiner
maintains that it would have been obvious to one of ordinary
skill in the art at the time of the invention to have modified
the primary references to include the tension support structure
of Urbanek. Id. (referencing figure 2 of Urbanek).2
Claims 27 and 28 include the additional limitation
of a shield. It is the examiner’s position that it would have
been obvious to one of ordinary skill in the art at the time of
the invention to have used Henderson’s shielding means to shield
the peripheral portion of the target of the primary references
Appeal No. 2001-2455
Application 08/439,490
10
“since shielding is well known in the art to protect other parts
of the apparatus from contamination.” Id., page 5.
For the reasons set forth below, we find that the
examiner has failed to establish a teaching or suggestion for
each of the recited claim elements and, therefore, has failed to
establish a prima facie case of obviousness. We focus our
discussion of the rejections on each of the independent claims.
Claim 1
Claim 1 is directed to a replaceable sputtering target
which includes a recessed peripheral rim. The rim includes a
tension maintaining support structure fixed at the center of the
rear face, the rear face having an annular inner water-sealing
surface thereon surrounding the tension maintaining support
structure. Claim 1. The examiner concedes that the primary
references do not discuss a center tension supporting structure.
Examiner’s Answer, page 4. However, the examiner maintains that
“Urbanek in figure 2 clearly shows a tension supporting structure
is an integral part of the target or detachably connected.” Id.
While this may be true, the examiner has failed to offer any
explanation as to why one of ordinary skill in the art would have
Appeal No. 2001-2455
Application 08/439,490
11
been motivated to have employed Urbanek’s tension maintaining
support structure in the apparatuses of the primary references.
See Kotzab, 217 F.3d at 1371, 55 USPQ2d at 1317 (“[P]articular
findings must be made as to the reason the skilled artisan, with
no knowledge of the claimed invention, would have selected the[]
components for combination in the manner claimed.”).
The Federal Circuit requires that the Board set forth
its findings and the grounds thereof as supported by the agency
record, and explain its application of the law to the found
facts. In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1433-34
(Fed. Cir. 2002). In the present case, the record is simply
devoid of any findings by the examiner as to why one of ordinary
skill in the art would have been motivated to have utilized
Urbanek’s tension supporting structure in the apparatuses of the
primary references.
Claim 14
Claim 14 is directed to a “removable” sputtering target
assembly which comprises both a replaceable target unit and a
cooling jacket connected to the back of the target unit. Landau
discloses a sputtering apparatus wherein the target is removable.
See, e.g., claim 1. However, there is no indication that a
Appeal No. 2001-2455
Application 08/439,490
12
cooling jacket, connected to the back thereof, is also removable.
Schuhmacher discloses an apparatus wherein the cooling channel is
positioned between a diaphragm and the base. The target is
connected to the base by means which are separate from the
means for connecting the diaphragm to the base. See column 3,
lines 34-39. Thus, while it is indicated that the target is
removable, there is no indication that an assembly comprising
both the target and cooling jacket are removable as required by
claim 14. Likewise, there is no disclosure or suggestion in
Kerschbaumer of a removable assembly comprising the target unit
and cooling jacket.
Claims 16 and 26
Claim 16 is directed to a sputtering cathode assembly
and claim 26 is directed to a sputtering apparatus which includes
a sputtering cathode assembly. The sputtering cathode assemblies
of claims 16 and 26 include target assemblies removably connected
to a housing, the assemblies including a replaceable target and a
cooling jacket. For the reasons set forth above with respect to
claim 14, the cited references fail to disclose or suggest
apparatuses wherein the target unit and cooling jacket are
removable.
Appeal No. 2001-2455
Application 08/439,490
13
Claim 40
Claim 40 recites a replaceable sputtering target which
comprises a circular target unit and recessed peripheral rim
including a tension maintaining support structure fixed at the
center of the rear face thereof, the rear face having an annular
inner water-sealing surface thereon surrounding the tension
maintaining support structure. For the reasons set forth above
in connection with Claim 1, the examiner has failed to establish
why one of ordinary skill in the art would have been motivated to
have modified the primary references in light of the teachings of
the secondary references to achieve these claimed features.
Claim 41
Claim 41 is directed to a method of replacing a
sputtering target in a sputtering apparatus which includes the
step of disconnecting a used target from the cathode assembly of
the apparatus by removing the used target with a cooling jacket.
As discussed above, none of the cited references disclose or
suggest an apparatus wherein the cooling jacket is removable
along with the target.
Appeal No. 2001-2455
Application 08/439,490
14
In view of the foregoing, we find that the examiner has
failed to establish a prima facie case of obviousness with
respect to claims 1-41. The rejections are reversed.
REVERSED

CHARLES F. WARREN )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
THOMAS A. WALTZ ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
LINDA R. POTEATE )
Administrative Patent Judge )
LRP:psb
Appeal No. 2001-2455
Application 08/439,490
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