Ex Parte Wu

Patent Trial and Appeal Board

May 26, 2016

12786260 (P.T.A.B. May. 26, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
121786,260 05/24/2010
11280 7590 05/31/2016
Lee & Hayes , pllc
601 West Riverside Ave., Suite 1400
Spokane, WA 99201
FIRST NAMED INVENTOR
Albert Wu
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.
MP3267 I MV1-0047US 2430
EXAMINER
BOYLE, ABBIGALE A
ART UNIT PAPER NUMBER
2816
NOTIFICATION DATE DELIVERY MODE
05/31/2016 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):
lhpto@leehayes.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ALBERT WU
Appeal2014-008767
Application 12/786,260
Technology Center 2800
Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
JAMES C. HOUSEL, Administrative Patent Judges.
PER CURIAM.
DECISION ON APPEAL 1
Appellant2 filed an appeal under 35 U.S.C. § 134(a) from the
Examiner's decision finally rejecting claims 1, 3, 5, 9, 10, 12, 13, and 17
under 35 U.S.C. § 103(a) as being unpatentable over the combination of
Slater,3 Akram,4 Kimura, 5 and Tsai6 and rejecting claims 18, 20, 22, and 23
1 Our decision refers to Appellant's Specification (Spec.) filed May 24,
2010, the Final Office Action (Final Act.) mailed September 30, 2013,
Appellant's Appeal Brief (Appeal Br.) filed March 19, 2014, the Examiner's
Answer (Ans.) mailed June 11, 2014, and Appellant's Reply Brief (Reply
Br.) filed August 8, 2014.
2 Appellant identifies the real party in interest as Marvell World Trade, Ltd.
Appeal Br. 2.
3 Slater, Jr., US 2006/0091565 Al, published May 4, 2006 ("Slater").
4 Akram et al., US 2001/0030371 Al, published Oct. 18, 2001 ("Akram").
5 Kimura, US 3,642,528, issued Feb. 15, 1972 ("Kimura").
6 Tsai et al., US 2008/0265385 Al, published Oct. 30, 2008 ("Tsai").
Appeal2014-008767
Application 12/786,260
under 35 U.S.C. § 103(a) as being unpatentable over the combination of
Tiziani7 in view of Slater. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
STATEMENT OF THE CASE
The subject matter on appeal relates to wirebond structures and
associated fabrication processes. Spec. i-f 2. Appellant discloses copper
wires as an emerging technology for wirebonding integrated circuits but that
copper wires do not form a reliable bond with some materials, such as
aluminum. Spec. i-f 3. Figure 1 is reproduced below.
11 : < ~~~ Mffl !~1~_,]] ; ' ! I
1:. .. •::. .. •:•:.· .•:•~::::::~::~]I25liff.u,0. u uu.:j
:,:.5G~j~!~
::
120 120 12Cr 120 ··126 12Ci 120
~11"':': 1·· r~ 1~1. · ·
Figure 1 schematically illustrates a cross sectional view of a semiconductor
package.
Appellant discloses a semiconductor package 100 including a
7 Tiziani et al., US 2004/0072396 Al, published Apr. 15, 2004 ("Tiziani").
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Appeal2014-008767
Application 12/786,260
semiconductor die 102 and a substrate 104. Spec. if 26. Wires 106 couple
the die 102 with the substrate 104. Spec. if 29. A mold compound 118
encapsulates the die 102 and structures, such as solder balls 120, couple the
substrate 104 with other electronic devices. Spec. iii! 31 and 32. Figure 2 is
reproduced below.
210 -··-'-
--.,,.,,,,,.,-,,,,.
2·10
Figure 2 illustrates an enlarged view of region 108 in Figure 1.
As depicted in Figure 2, a bond pad 214, which is located on a surface
of a die 202, is electrically coupled to an integrated circuit device 220 via
interconnect structures 216, 218. Spec. if 34. Appellant discloses an
embodiment in which the bond pad 214 comprises aluminum. Spec. if 3 5.
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Appeal2014-008767
Application 12/786,260
A passivation layer 210 is located on a surface of the die 202, with portions
removed to provide openings over bond pads 214. Spec i-f 37. Appellant
discloses a bonding material 212 on the bonding pad 214 to facilitate
bonding between the bond pad 214 and a wire 206. Spec. i-f 38. Appellant
discloses an embodiment in which the bonding material 212 comprises gold
and the wire 206 comprises copper. Id.
Independent claim 1, reproduced below from the Claims Appendix to
Appellant's Appeal Brief, is illustrative of the subject matter on appeal. The
limitations at issue are italicized.
1. An apparatus comprising:
a semiconductor die having a surface, wherein the
semiconductor die includes one or more integrated circuit
devices;
a bond pad formed on the surface of the semiconductor
die, wherein the bond pad comprises aluminum (Al), and wherein
the bond pad is electrically coupled to the one or more integrated
circuit devices of the semiconductor die;
a bonding material formed as a film on a first portion of
the bond pad, wherein the bonding material comprises gold (Au);
a passivation layer formed on the surface of the
semiconductor die, wherein a portion of the passivation layer is
removed to provide an opening in the passivation layer over the
bond pad, and wherein the portion of the passivation layer is
removed such that the passivation layer is positioned to cover a
second portion of the bond pad not including the first portion of
the bond pad; and
a wire coupled to the film of the bonding material through
the opening in the passivation layer, wherein the wire comprises
copper (Cu), and wherein the film of the bonding material
comprised of gold (Au) facilitates bonding of the wire comprised
of copper (Cu) to the bond pad comprised of aluminum (Al) that
is formed on the surface of the semiconductor die.
Appeal Br. 13.
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Application 12/786,260
ANALYSIS
Rejection under§ 103 over Slater, Akram, Kimura, and Tsai
We sustain this rejection based on the findings of fact, conclusions of
law, and rebuttals to arguments well expressed by the Examiner in the Final
Office Action and the Answer. The following comments are added for
emphasis.
Appellant traverses the§ 103(a) rejection of claim 1 by asserting none
of the applied references disclose an apparatus including a bond pad
comprising aluminum, a bonding material comprising gold and formed as a
film on a first portion of the bond pad, and a wire comprising copper
coupled to film of the bonding material, as recited in claim 1. Appeal Br. 6,
7, and 9; Reply Br. 4. Specifically, Appellant asserts Kimura does not
disclose, among other things, a bonding material comprising gold and a wire
comprising copper. Appeal Br. 7. However, the Examiner found Slater
discloses a semiconductor apparatus including a bonding material
comprising gold and found Tsai discloses a semiconductor apparatus
including a wire comprising copper. Final Act. 2 and 4. Appellant does not
dispute the Examiner's findings.
Moreover, Appellant contends Tsai does not disclose a bond pad
comprising aluminum. Appeal Br. 9. However, the Examiner found Kimura
discloses an ohmic contact comprising aluminum and concludes it would
have been obvious to use aluminum in the bond pad of Slater. Final Act. 4.
Appellant does not dispute the Examiner's finding or the Examiner's reason
to combine Slater and Kimura. Therefore, Appellant's arguments do not
address the Examiner's rejection and are not persuasive of reversible error.
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Application 12/786,260
Appellant traverses the Examiner's conclusion to use copper wires, as
disclosed by Tsai, in the semiconductor apparatus of Slater to provide good
adhesion with gold bonding material and to save cost. Appeal Br. 9.
Specifically, Appellant argues the gold bonding material disclosed by Tsai is
located on fingers of a substrate, not a bond pad. Appeal Br. 8-9; Reply Br.
2--4. The Examiner found Tsai discloses copper wires are less expensive
than gold wires and that gold has good adhesion to copper wires. Final Act.
4. The disclosure of Tsai supports the Examiner's findings, including a
finding of a reason to combine Slater and Tsai. Tsai i-fi-12 and 7. In addition,
the Examiner determined that although, the gold stud bumps of Tsai are
located on fingers of a substrate, one of ordinary skill in the art would have
recognized the advantage of the enhanced bondability between copper and
gold disclosed by Tsai and applied this advantage to a bond between a
copper wire and gold bonding material on a bond pad of a semiconductor
die. Ans. 5-7. Therefore, Appellant's arguments are not persuasive of
reversible error.
Appellant further contends Akram teaches away from the use of
wiring, citing Akram's disclosure in paragraphs 42 and 45. Appeal Br. 7.
This argument is unpersuasive of reversible error. When the prior art
teaches away from a combination, that combination is more likely to be
nonobvious, KSR Int'!. Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007), but to
teach away, a reference must discourage one of ordinary skill in the art from
following the path set out in the reference, or lead that person in a direction
divergent from the path that was taken by the applicant. In re Gurley, 27
F.3d 551, 553 (Fed. Cir. 1994). Various types of teachings may support a
finding of "teaching away." These include known disadvantages in old
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Application 12/786,260
devices that would naturally discourage the search for new inventions,
teachings leaving the impression that the product would not have the
property sought by the applicant, and reference combinations that would
produce a seemingly inoperative device. Id. (citations omitted). "Although
a reference that teaches away is a significant factor to be considered in
determining unobviousness, the nature of the teaching is highly relevant, and
must be weighed in substance." Id. For instance, when there is nothing
within the reference teaching that the claimed element should not, or cannot,
be used, and further cited prior art teaches the propriety of employing the
missing element, the teachings of both references must be weighed
together. Para-Ordnance Mfg., Inc. v. SGS Importers Int'!, Inc., 73 F.3d
1085, 1090 (Fed. Cir. 1995).
The Examiner relied upon Akram merely for suggesting the use of
integrated circuit devices in the apparatus of Slater. Ans. 3. Paragraph 42 of
Akram discloses ( 1) integrated circuits with peripheral bond pads and wiring
connected to the bond pads and (2) integrated circuits with bond pads
distributed in area arrays. Akram discloses the latter require a layer of traces
typically made via several steps of metal deposition, masking, and etching
but these steps are eliminated when fabricating the integrated circuit design
disclosed by Akram. Akram i-f 42. Thus, steps eliminated in the fabrication
process of Akram do not include bonding wires to bond pads. Additionally,
the steps eliminated in paragraph 45 of Akram are re-patterning steps (i.e.,
metal deposition, masking, and etching) normally used to apply a different
integrated circuit design, such as the design of Akram, to existing integrated
circuit designs, not the elimination of wiring. Thus, we are unpersuaded that
Akram teaches away from the use of bond wires as urged by Appellant.
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For the reasons discussed above and for the reasons expressed in the
Answer, the Examiner's§ 103(a) rejection of claim 1 over the combination
of Slater, Akram, Kimura, and Tsai is sustained. Appellant has not
advanced separate arguments for any of claims 3, 5, 9, 10, 12, 13, and 17.
Appeal Br. 9 and 10. Therefore, the§ 103(a) rejection of claims 1, 3, 5, 9,
10, 12, 13, and 17 is sustained.
Rejection under§ 103 over Tiziani and Slater
We sustain this rejection based on the findings of fact, conclusions of
law, and rebuttals to arguments well expressed by the Examiner in the Final
Office Action and the Answer. The following comments are added for
emphasis.
For the§ 103(a) rejection over the combination of Tiziani and Slater,
we select claim 18 as representative for resolving the issues on appeal.
Appellant contends Tiziani and Slater do not disclose or suggest:
... a wire coupled to the bonding material through the opening in
the passivation layer, wherein the wire comprises copper (Cu),
and wherein the bonding material comprised of gold (Au)
facilitates bonding of the wire comprised of copper (Cu) to the
bond pad comprised of aluminum (Al) that is formed on the
semiconductor die,
as recited in claim 18.
Appeal Br. 11.
The Examiner found Tiziani discloses a bond pad comprising
aluminum formed on a semiconductor die, a bonding material comprising
gold, and a wire comprising copper coupled to the bonding material. Final
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Application 12/786,260
Act. 9-10. The disclosure of Tiziani8 supports the Examiner's findings. The
Examiner found that although Tiziani does not disclose a passivation layer,
Slater discloses the use of a passivation layer on a semiconductor die,
including the removal of a portion of the passivation layer to provide an
opening through which a wire can be coupled to bonding material. Final
Act. 10-11. The disclosure of Slater9 also supports the Examiner's findings.
Appellant does not contest the Examiner's findings. Indeed,
Appellant's arguments do not address the Examiner's rejection because the
arguments do not address the Examiner's findings. Moreover, Appellant
argues Slater does not disclose the recitations of claim 18 by referencing the
Examiner's findings relating to Slater in the rejection of claim 1. Appeal Br.
11. As stated by the Examiner, these findings are directed to features not
recited in claim 18, such as a semiconductor die including one or more
integrated circuits, or are addressed by the Examiner's reliance upon Tiziani
for the disclosure of a wire comprising copper and a bond pad comprising
aluminum. Ans. 8-9. As a result, Appellant's arguments are not persuasive
of reversible error.
For the reasons discussed above and for the reasons expressed in the
Answer, the Examiner's§ 103(a) rejection of claim 18 over the combination
of Tiziani and Slater is sustained. Appellant has not advanced separate
arguments for any of claims 20, 22, and 23. Appeal Br. 12. Therefore, the
§ 103(a) rejection of claims 18, 20, 22, and 23 is sustained.
8 Tiziani i-fi-15, 15, 19, 20, 36, and 37.
9 Slater i-fi-1 4, 18, and 19.
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Appeal2014-008767
Application 12/786,260
DECISION
On the record before us and for the reasons in the Examiner's Answer
and above, the Examiner's rejections are affirmed.
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
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