Ex Parte HUAI

Board of Patent Appeals and Interferences

Jul 25, 2003

09349745 (B.P.A.I. Jul. 25, 2003)

1 In rendering our decision, we have considered Appellant’s arguments presented in the Brief,
filed August 6, 2001 and the Reply Brief, filed January 24, 2002.
2 The Appellant has indicated that claims 11 and 18 have been cancelled. (Brief, p. 2).
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is not binding precedent of the Board.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. 18
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte YIMING HUAI
____________
Appeal No. 2002-1212
Application No. 09/349,745
____________
ON BRIEF
____________
Before KIMLIN, JEFFREY T. SMITH and MOORE, Administrative Patent Judges.
JEFFREY T. SMITH, Administrative Patent Judge.
DECISION ON APPEAL
Applicant appeals the decision of the Primary Examiner finally rejecting claims 1
to 10, 12 to 17 and 19 to 23, all of the pending claims.1, 2 We have jurisdiction under 35
U.S.C. § 134.
Appeal No. 2002-1212
Application No. 09/349,745
2
CITED PRIOR ART
As evidence of unpatentability, the Examiner relies on the following references:
Coffey et al. (Coffey) 5,583,725 Dec. 10, 1996
Kim et al. (Kim) 5,637,235 Jun. 10, 1997
Kanai 5,850,323 Dec. 15, 1998
The Examiner has rejected claims 1 to 10, 12 to 17 and 19 to 23 as unpatentable
under 35 U.S.C. § 103(a) as obvious over the combination of Coffey and Kanai; and
claims 1 to 10, 12 to 17 and 19 to 23 as unpatentable under 35 U.S.C. § 103(a) as obvious
over the combination of Coffey and Kim. (Answer, pp. 3 to 9).
DISCUSSION
We have carefully reviewed the claims, specification and applied prior art,
including all of the arguments advanced by both the Examiner and Appellant in support
of their respective positions. This review leads us to conclude that the Examiner’s § 103
rejections are not well founded. See In re Oetiker, 977 F.2d 1443, 1445, 24 USPQ2d
1443, 1444 (Fed. Cir. 1992); In re Piasecki, 745 F.2d 1468, 1471-72, 223 USPQ 785,
787-88 (Fed. Cir. 1984). Rather than reiterate the conflicting viewpoints advanced by the
Examiner and Appellant concerning the above-noted rejection, we refer to the Answer
and the Brief and Reply Brief.
Appeal No. 2002-1212
Application No. 09/349,745
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Appellant’s invention is directed to a magnetoresistive (MR) spin valve sensor for
reading magnetically stored data. The magnetized bits on the recording media change the
magnetization between the pinned layer and the free layer. The spin valve sensor detects
changes in current electrical resistance which occurs as a result of the orientation of the
magnetization of ferromagnetic layers within the sensor. (Specification, p. 1). Claim 1,
which is representative of the claimed invention, appears below:
1. A top spin valve comprising
(i) a seed layer comprising Ni and Cr;
(ii) a free layer on the seed layer;
(iii) a pinned layer overlying the free layer; and
(iv) a spacer layer between the pinned and free layers.
Since we reverse the Examiner’s rejections, we need to address only the
independent claims, i.e., claims 1, 13 and 20.
The Examiner rejected claims 1 to 10, 12 to 17 and 19 to 23 as unpatentable under
35 U.S.C. § 103(a) as obvious over the combination of Coffey and Kanai.
The top spin valve of Appellant’s independent claims requires at least (i) a seed
layer comprising Ni and Cr, (ii) a free layer on the seed layer, (iii) a pinned layer
overlying the free layer, and (iv) a spacer layer between the pinned and free layers or a
method of forming the same.
Appeal No. 2002-1212
Application No. 09/349,745
4
The Examiner asserts the invention of Coffey differs from the claimed invention in
that there is no express disclosure of a seed layer containing NiFeCr. (Answer, p. 4). To
remedy this deficiency, the Examiner relies on Kanai. According to the Examiner, Kanai
discloses “a MR sensor having a pre-seed Ta layer (12a) is part of a seed layer also
having a NiFeCr (12c) seed layer under a MR sensor layer structure.” (Answer, p. 4).
The Examiner concludes “one of ordinary skill in the art would have been motivated to
furnish the MR sensor assembly having a seed layer under the MR sensor layers as shown
in Coffey et al ‘725 with the seed layer being made of NiFeCr as shown by Kanai ‘323
because it would have allowed further abatement of noise in the head by allowing a
marked decrease in the anisotropic magnetoresistive effect.” (Answer, Paragraph
bridging pages 4 and 5).
Appellant argues that the free layer 33 of Coffey serves a different function and
has different magnetic properties than the antiferromagnetic NiMn layer 13 of Kanai.
Appellant argues that there is no reason to believe that the seed layer(s) of Kanai would
provide Coffey with a noise reduction. Appellant specifically states “the two-layer
structure 12 of Kanai et al. is specifically tailored to seeding layers of NiMn (col. 1 lines
18-19) and NiMn alloys (col. 5 lines 47-50), but nowhere does Kanai et al. teach or
suggest that it could be applied to seeding any other alloy class. As described above, both
Appeal No. 2002-1212
Application No. 09/349,745
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of the layers of the two-layer structure 12 are required to impart the desired FCT crystal
structure to the NiMn layer 13 (col. 2 lines 21-31). However, the free layer 35 of Coffey
et al. is neither NiMn nor a NiMn alloy, but is instead a soft magnetic material such as Co
or a Co alloy (col. 4 line 61 and col 7 lines 13-17).” (Brief, pp. 5-6).
The Examiner has not adequately responded to Appellant’s argument that there is
no reason to believe that the seed layer(s) of Kanai would provide Coffey with a noise
reduction. The Examiner’s response, Answer pages 9-10, does not indicate that the Co or
Co alloy free layer of Coffey would experience the same or similar crystal structure as
Kanai’s NiMn or NiMn alloy. Thus, there is no reasonable basis to believe that Coffey
would experience the same reduction in noise as Kanai.
The Examiner also rejected claims 1 to 10, 12 to 17 and 19 to 23 as unpatentable
under 35 U.S.C. § 103(a) as obvious over the combination of Coffey and Kim.
As stated above, the Examiner recognized that Coffey did not disclose a seed layer
containing Ni and Cr as required by claims 1, 13 and 20. To remedy this difference the
Examiner asserts that Kim discloses a MR sensor having a NiCr buffer seed layer under a
MR sensor layer structure. (Answer, p. 7). The Examiner concludes that “one of
ordinary skill in the art would have been motivated to furnish the MR sensor assembly
having a seed layer under the MR sensor layers as shown in Coffey et al ‘725 with the
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seed layer being made of NiCr as shown by Kim et al ‘235 because the MR cofficient and
thermal stability of the MR sensor would have been significantly improved; see column 4,
lines 53-59 or Kim et al ‘235.” (Answer, p. 7).
We, like the Appellant (Brief, p. 7), have reviewed the cited portion of the Kim
reference and do not find support for the rationale advance by the Examiner. The
Examiner has failed to address the Appellant’s concerns raised in the Brief. Thus, we
conclude that the Examiner’s rejection is based on speculation. Speculation is not a
sufficient basis for a prima facie case of obviousness. See In re Warner, 379 F.2d 1011,
1017, 154 USPQ 173, 178 (CCPA 1967); In re Sporck, 301 F.2d 686, 690, 133 USPQ
360, 364 (CCPA 1962). The rejection is reversed.
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Application No. 09/349,745
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CONCLUSION
For the above reasons, and those stated in the Briefs, we conclude that the
Examiner has not carried the burden of establishing a prima facie case of obviousness of
the invention recited in any of the Appellant’s claims. Consequently, we reverse the
Examiner’s 35 U.S.C. § 103 rejections.
REVERSED
)
)
EDWARD C. KIMLIN )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
JEFFREY T. SMITH ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
JAMES T. MOORE )
Administrative Patent Judge )
JTS/kis
Appeal No. 2002-1212
Application No. 09/349,745
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