Ex parte KEEL et al.

Board of Patent Appeals and Interferences

Oct 28, 1999

08188078 (B.P.A.I. Oct. 28, 1999)

Application for patent filed January 27, 1994,1
entitled "Mo-Au Gold Seedlayer In Thin Film Heads," which is a
continuation-in-part of PCT Application PCT/US93/11571, filed
November 23, 1993.
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THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the Board.
_______________
Paper No. 25
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte BEAT G. KEEL
and FRANK E. STAGEBERG

Appeal No. 1996-3811
Application 08/188,0781

ON BRIEF

Before BARRETT, KRASS, and FRAHM, Administrative Patent
Judges.
BARRETT, Administrative Patent Judge.
Appeal No. 1996-3811
Application 08/188,078
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DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from
the final rejection of claims 1-19.
We reverse.
BACKGROUND
The invention is directed to a thin film head and
method of making such a head, wherein seedlayers which
provide a bond to both the underlayer and the magnetic
material of the pole are formed of non-magnetic material.
When writing data to a disk, write current in a coil
orients magnetic domains in the pole magnetic material so
that the poles generate a desired magnetic field. When the
write current is removed, the magnetic domains should return
to a relaxed or stable state. However, in some cases the
write current causes an irreversible orientation of magnetic
domains in the magnetic material which causes distortion in
read signals generated by the head during a subsequent read
operation. Appellants state that they discovered that the
magnetic seedlayers increase external magnetic force on the
magnetic layers, thereby increasing the likelihood that the
head will not return to a stable state following a write
Appeal No. 1996-3811
Application 08/188,078
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excitation. The claimed invention requires two non-magnetic
seedlayers abutting respective top and bottom pole pieces.
Claim 1 is reproduced below.
1. A thin film head/slider assembly comprising:
a substrate;
a first non-magnetic seedlayer supported by the
substrate;
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Application 08/188,078
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a bottom magnetic core piece positioned over and
contacting the first non-magnetic seedlayer;
a second non-magnetic seedlayer;
a top magnetic core piece positioned over and
contacting the second non-magnetic seedlayer;
and
a gap comprising a non-magnetic material
sandwiched
between at least a portion of the bottom core
piece and at least a portion of the second
non-magnetic seedlayer.
The Examiner relies on the following prior art:
Kaminaka et al. (Kaminaka) 4,716,484 December 29,
1987
Cohen et al. (Cohen) 5,059,278 October 22,
1991
Frey et al. (Frey) 5,333,086 July 26,
1994
(filed March 29,
1993)
Claims 1-3, 5-7, 9, 12-15, and 17-19 stand rejected
under 35 U.S.C. § 103 as being unpatentable over Kaminaka
and Frey. The Examiner finds that figure 5 of Kaminaka
discloses a thin film head having a substrate (X1, X2), a
first seedlayer supported by the substrate (electrode 26), a
bottom magnetic core piece positioned over and contacting
the first magnetic seedlayer (lower magnetic core 16), a
second magnetic seedlayer (electrode 44), a top magnetic
Appeal No. 1996-3811
Application 08/188,078
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core piece (upper magnetic core 41), and a gap comprising a
non-magnetic material sandwiched between a portion of the
core bottom piece and the second non-magnetic seedlayer
(non-magnetic insulating layer 37). The Examiner finds the
following differences between Kaminaka and the claimed
subject matter (Final Rejection, page 3): "Kaminaka et al
does not (i) explicitly show that the seedlayers are
non-magnetic, or (ii) teach that the non-magnetic gap is of
the same composition as the seedlayer." The Examiner finds
that figure 7 of Frey discloses a thin film head having a
non-magnetic seedlayer 212 on which pole 222 is deposited.
The Examiner concludes that it would have been obvious to
make the seedlayers of Kaminaka from a non-magnetic material
as shown in Frey "to prevent the seedlayer from acting like
an additional (third) magnetic pole, thus ensuring that the
readback waveform is not perturbed (see Frey et al:
column 5, line 63 - column 6, line 2)" (Final Rejection,
pages 4-5). The Examiner also concludes that it would have
been obvious to make the non-magnetic gap of the head in
Kaminaka to have the same composition as the seedlayer "to
reduce the number of materials required to produce the head
Appeal No. 1996-3811
Application 08/188,078
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by making the layers (both non-magnetic by necessity) from
the same substance" (Final Rejection, page 4).
Claims 4, 8, 10, 11, and 16 stand rejected under
35 U.S.C. § 103 as being unpatentable over Kaminaka, Frey,
and Cohen.
We refer to the Final Rejection (Paper No. 12), the
Examiner's Answer (Paper No. 17) (pages referred to as
"EA__"), and the Supplemental Examiner's Answer (Paper
No. 20) (pages referred to as "SEA__") for a statement of
the Examiner's position and to the Appeal Brief (Paper
No. 16) (pages referred to as "Br__") and the Reply Brief
(Paper No. 19) (pages referred to as "RBr__") for a
statement of Appellants' arguments thereagainst.
OPINION
Grouping of claims
Appellants group claims 1-16 to stand or fall together
and claims 17-19 to separately stand or fall together (Br4).
Thus, it is only necessary to address the broadest
independent claim and the corresponding one of dependent
claims 17-19. Claim 1 is considered representative of
claims 1-16.
Appeal No. 1996-3811
Application 08/188,078
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Appellants argue that the Examiner erroneously
indicates a grouping in accordance with the issues, and not
the grouping of claims as set forth by Appellants (RBr1).
We agree. The Examiner's statement that claims 1-3, 5-7, 9,
12-15, and 17-19 do not stand or fall together is in error
because Appellants have only argued limitations found in the
independent claims 1, 5, and 9 and a limitation found in
claims 17-19. It is not necessary to address each claim
separately. The Examiner's statement that claims 4, 8, 10,
11, and 16 stand or fall together is in error because
Appellants have not argued any of the claims separately.
The source of the problem is evident in the Examiner's
statement that (SEA3): "Declaring claims 1-16 to be a
particular grouping as proposed by Appellant is not
appropriate because these claims span two separate grounds
of rejection." However, claims 4, 8, 10, 11, and 16 in the
second rejection are not argued separately and are dependent
on claims rejected in the first rejection; i.e., Appellants
have elected to have all the dependent claims in the second
rejection stand or fall with the broadest of the independent
claims in the first rejection. There is nothing wrong with
Appeal No. 1996-3811
Application 08/188,078
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this grouping and, in fact, it simplifies the analysis.
Appellants are not trying to gain an advantage by grouping
unlike claims together. Thus, we stay with Appellants'
grouping.
Obviousness
Appellants argue (Br5, Sec. A) that while Kaminaka is
silent as to the material forming the seedlayer, one of
ordinary skill in the art would presume from Frey's
disclosure that "use of a magnetic seed layer is
conventional in formation of a two-pole thin film inductive
head" (Frey, col. 5, lines 63-65) and from Appellants'
statement that the prior art as of 1993 used magnetic
seedlayers, that Kaminaka's seedlayers are magnetic. Frey's
disclosure that magnetic seedlayers were conventional does
not prove that all seedlayers were magnetic. In fact, the
existence of "conventional" magnetic seedlayers might
suggest that "non-conventional" non-magnetic seedlayers were
known, especially since Frey does not disclose any
non-magnetic seedlayer materials, which suggests that such
materials were known to those of ordinary skill in the art.
However, we have no evidence on this record that
Appeal No. 1996-3811
Application 08/188,078
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non-magnetic seedlayers were used in heads other than the
type shown in Frey. Appellants' statement that the prior
art known to Appellants used magnetic seedlayers does not
prove that all seedlayers were magnetic since an applicant
is not necessarily aware of all relevant prior art.
However, Kaminaka is silent about the material of the
seedlayer; thus, it does not disclose or suggest
non-magnetic seedlayers.
Appellants argue (Br8, Sec. C) that even if one were to
add Frey's wedge and bottom non-magnetic seedlayer, the
combination would still not disclose a non-magnetic
seedlayer for the upper pole piece. The Examiner states
that the rejection is not based on the incorporation of the
wedge of Frey into Kaminaka, but that "Frey et al is relied
upon only for teaching that magnetic seedlayers can perturb
the readback waveform and that non-magnetic seedlayers can
alleviate such a problem" (EA8). We disagree with the
Examiner's findings about the teachings of Frey as discussed
infra. In our opinion, Frey suggests modifying the bottom
pole of Kaminaka to have an angle for the purpose of
reducing the secondary pulse, which would require the
Appeal No. 1996-3811
Application 08/188,078
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non-magnetic seedlayer and wedge. However, we agree with
Appellants that Frey does not suggest modifying the
non-magnetic seedlayer for the upper pole piece.
Appellants argue (Br5-7, Sec B) that Frey's only
purpose for providing a non-magnetic seedlayer is to prevent
the portion 213 of the seedlayer, which is separated from
pole 222 by a wedge of non-magnetic material 215A, from
forming a third pole and, thus, Frey provides no reason to
make Kaminaka's seedlayers non-magnetic because there is no
danger of creating a third pole. "More particularly, since
both of Kaminaka's magnetic seedlayers are contiguous [to]
their respective poles, there is no danger that either might
act as a third pole separated from the bottom pole by
insulating material." (Br6.)
The Examiner responds (EA7-8):
The Examiner disagrees - by adding a third magnetic
body at the air bearing surface, a third pole would be
formed regardless of the separation between the
magnetic bodies. The "perturbing" effect may be
decidedly less pronounced if a wedge is not included
(i.e. if the magnetic bodies are close together or even
touching), but this does not mean that adding a
magnetic body will not perturb the waveform as taught
in Frey et al.
Appeal No. 1996-3811
Application 08/188,078
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The Examiner stated in the Final Rejection "that creating
the seedlayer from a non-magnetic material would prevent the
seedlayer from acting like an additional magnetic pole, thus
ensuring that the readback waveform is not perturbed" (FR6),
which would be apparent whether or not a "wedge" exist.
The Examiner's reasoning presents a factual question of
what Frey disclosed to one of ordinary skill in the art.
Motivation is a question of fact. Frey discloses (col. 5,
line 66, to col. 6, line 2): "[P]ortion 213 of the seed
layer (under wedge 215A) will extend out to the air bearing
surface of the finished head and will act as a third pole if
the layer is magnetic. This would perturb the readback
waveform." We agree with Appellants that this teaches
making the seedlayer from non-magnetic material only because
there is a wedge (gap) between the seedlayer and the pole.
If the wedge were not present, even a magnetic seedlayer
could not form a third pole as stated by the Examiner
because the seedlayer would form part of the pole as in a
conventional head. There is no analogous separation between
the seedlayers and the magnetic core pieces in Kaminaka that
would require the use of a non-magnetic seedlayer.
Appeal No. 1996-3811
Application 08/188,078
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Frey teaches that shaping the magnetic poles at an
acute angle helps preserve the waveform by lengthening the
secondary pulses in the readback signal and, hence, reducing
the significance of the secondary pulses within a readback
window waveform (col. 2, line 65, to col. 3, line 5; figure
4). We find no factual evidence in Frey to support the
Examiner's finding that a magnetic seedlayer formed in
contact with a magnetic pole may perturb the waveform more
than the magnetic pole itself. Frey does not teach or
suggest that the thickness of the pole perturbs the
waveform. Therefore, it appears that the Examiner's
reasoning is based on hindsight.
The motivation in the prior art to combine the
references does not have to be identical to that of the
applicant to establish obviousness. In re Dillon, 919 F.2d
688, 693, 16 USPQ2d 1897, 1901 (Fed. Cir. 1990) (in banc),
overruling in part In re Wright, 848 F.2d 1216,
6 USPQ2d 1959 (Fed. Cir. 1988). Thus, the fact that Frey
does not disclose the problem discovered by Appellants (that
the magnetic seedlayer increases the external magnetic force
on the magnetic layers, thereby increasing the likelihood
Appeal No. 1996-3811
Application 08/188,078
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that the head will not return to a stable state following a
write excitation) does not necessarily bar a conclusion of
obviousness. Nevertheless, here we find no teaching or
suggestion in Frey that would have led one having ordinary
skill in the art to make the seedlayers in Kaminaka from
non-magnetic material.
Appeal No. 1996-3811
Application 08/188,078
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For the reasons stated above, we conclude that the
Examiner has failed to establish a prima facie case of
obviousness. Cohen does not cure the deficiency of the
combination of Kaminaka and Frey. The rejections of
claims 1-19 are reversed.
REVERSED
ERROL A. KRASS )
Administrative Patent Judge )
)
)
)
) BOARD OF
PATENT
LEE E. BARRETT ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
ERIC S. FRAHM )
Administrative Patent Judge )
Appeal No. 1996-3811
Application 08/188,078
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