Atty. Docket No. MIT-7581L-RX1
`
`IN THE UNITED STATES PATENT & TRADEMARK OFFICE
`
`IN RE PATENT OF:
`
`Joseph BERNSTEIN et al.
`
`PATENT NO.: 6,057,221
`
`SERIAL NO.: 08/825,808
`
`ISSUE DATE: May 2, 2000
`
`FILING DATE: April3, 1997
`
`CONTROL NO.: 90/011,607
`
`ASSIGNEES:
`
`MASSACHUSETTS INSTITUTE OF TECHNOLOGY;
`THE UNIVERSITY OF MARYLAND
`
`FOR: LASER-INDUCED CUTTING OF METAL INTERCONNECT
`
`I hereby certify that this document is being transmitted to the USPTO or deposited with the United States Postal
`Service as first class mail in an envelope addressed to Commissioner for Patents, P.O. Box 1450, Alexandria, VA
`22313-1450, on August 12,2011.
`
`By: ________ ~/~J~u~d~v~R~v~a=n~/ __________ ___
`Judy Ryan
`
`PATENT OWNERS' STATEMENT IN
`EX PARTE REEXAMINATION PURSUANT TO 37 C.P.R. 1.530
`
`Mail Stop EX PARTE REEXAM
`COMMISSIONER FOR PATENTS
`P.O. BOX 1450
`ALEXANDRIA, VA 22313-1450
`
`SIR:
`
`Patentees respectfully submit the following Patent Owners' Statement pursuant to 37
`
`C.P.R. §1.530 and M.P.E.P. §§ 2249 and 2250, detailing why the subject matter as claimed by
`
`U.S. Pat. No. 6,057,221 (hereinafter the "'221 patent") is not anticipated or rendered obvious by
`
`the references on which the substantial new questions of patentability (hereinafter "SNQ") are
`
`based.
`
`IPR2015-01087 - Ex. 1039
`Micron Technology, Inc., et al., Petitioners
`1
`
`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`Patent Owners' Statement Regarding the References on which the Substantial New Questions of
`
`Patentability are Based (37 C.P.R. § 1.530)
`
`Claims 1-2:
`
`Reexamination of Claims 1-2 is moot, as Claims 1-2 have been canceled (see the
`
`Corrected Pre-Amendment filed April14, 2011 [hereinafter the "Amendment"]).
`
`Claim 3:
`
`Claim 3 has been rewritten in independent form and includes the limitations of Claim 1.
`
`Claim 3 recites a method for cutting a link between interconnected circuits, comprising directing
`
`a laser upon an electrically-conductive cut-link pad conductively bonded between a first
`
`electrically-conductive line and a second electrically-conductive line on a substrate, the cut-link
`
`pad having substantially less thermal resistance per unit length than each of the first and
`
`second electrically-conductive lines, wherein the width of the cut-link pad is at least ten
`
`percent greater than the width ofeach ofthe first and second electrically-conductive lines, and
`
`maintaining the laser upon the cut-link pad until the laser infuses sufficient energy into the cut(cid:173)
`
`link pad to break the conductive link across the cut-link pad between the pair of electrically(cid:173)
`
`conductive lines, wherein the electrically-conductive cut-link pad has an inner surface facing the
`
`substrate and an opposing outer surface facing away from the substrate, the first and second
`
`electrically-conductive lines extending from the inner surface into the substrate (see the
`
`Amendment).
`
`Reexamination of Claim 3 has been requested in view of Koyou, Japan Pat. Appl. Pub.
`
`No. 8-213465, published Aug. 20, 1996 (hereinafter "Koyou"). Claim 3 is not anticipated or
`
`rendered obvious in view of Koyou because Koyou does not disclose or suggest a cut-link pad
`
`that has substantially less thermal resistance per unit length than each of the first and second
`
`electrically-conductive lines. Furthermore, Koyou does not affirmatively disclose that the width
`
`of the cut-link pad is at least ten percent greater than the width of each of the first and second
`
`electrically-conductive lines.
`
`Page 2 of26
`
`2
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`As shown in FIGS. 1(a)-(b) ofKoyou, the width of fuse pad 1 is greater than the width of
`
`contact holes 2a and 2b and of interconnect lines 3a and 3b. However, the material of the fuse
`
`pad 1 is continuous with and formed at the same time as the material in the contact holes 2a-2b,
`
`so material in the contact holes 2a-2b is within the laser spot (note the depressions in fuse
`
`member 1 in the regions of the contact holes 2a-2b ). Therefore, the material in each of the
`
`contact holes 2a and 2b is part ofthe fuse, and these portions of the fuse in the contact holes 2a
`
`and 2b are not "first and second electrically-conductive lines." Additionally, the width of the
`
`interconnect lines 3a and 3b is greater than the width of contact holes 2a and 2b. Thus, since the
`
`material in the narrow contact holes 2a and 2b is part of the fuse, and since at least part of the
`
`material in the holes 2a and 2b is irradiated by the laser, the portions of the fuse pad 1 that are in
`
`the contact holes 2a and 2b have a thermal resistance that is either equal to or greater than the
`
`thermal resistance of the interconnect lines 3a and 3b.
`
`The material in each of the relatively narrow contact holes 2a and 2b is not an
`
`"electrically conductive line" since it is part of the fuse structure 1, it is completely within the
`
`laser spot 5, and it is at least partially irradiated by the laser (see e.g., paragraph [0013] and
`
`FIGS. 1(a)-(b) of Koyou). Additionally, the portions of the fuse member 1 in the contact holes
`
`2a and 2b effectively increase the thermal resistance per unit length of the fuse 1 within the laser
`
`beam spot 5 (see e.g., FIGS. 1(a)-(b) of Koyou). This situation is demonstrated more clearly in
`
`FIG. 2 ofKoyou, discussed below.
`
`The interconnect lines 3a and 3b in FIGS. 1(a)-(b) of Koyou also are not "electrically
`
`conductive lines" as defined in Claim 3 since they are wider than the material in the relatively
`
`narrow contact holes 2a and 2b (which is at least partially part of the fuse pad). Based on
`
`dimensions alone (Koyou does not suggest that the interconnect lines 3a and 3b are made of a
`
`different material from the fuse 1 ), the wider interconnect lines 3a and 3b presumably have a
`
`lower thermal resistance per unit length than the material in the relatively narrow contact holes
`
`2a and 2b, which is part of the fuse structure. Thus, the cut-link pad does not have less thermal
`
`resistance per unit length than interconnect lines 3a and 3b.
`
`Page 3 of26
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`3
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`In the embodiment shown in FIG. 2 ofKoyou, the combined length L of fuse member 10
`
`and conductive portions 1 Oa and 1 Ob are completely within the illumination spot diameter D of
`
`the laser beam. Conductive portions 1 Oa and 1 Ob are selected to be smaller in cross-sectional
`
`area than fuse member 10, thereby increasing the thermal resistance of the contact portion
`
`relative to the fuse member 10. The electrically conductive portions lOa and lOb may also be
`
`formed from materials other than the material of fuse member 10, but the materials for portions
`
`1 Oa and 1 Ob should be selected to have thermal resistances as great as possible (see paras.
`
`[0016]-[0017] and FIG. 2 ofKoyou; emphasis added). Consequently, since portions lOa and lOb
`
`of fuse 10 are completely within the laser spot, portions 1 Oa and 1 Ob increase the thermal
`
`resistance per unit length of fuse 10, especially relative to the conductive lines connected thereto.
`
`Koyou discloses a third embodiment in FIG. 3, including a fuse member 20 and contact
`
`holes 21 a and 21 b. Koyou is also silent with regard to the relative widths of the fuse member 20
`
`and the material filling each of the contact holes 2la and 2lb. Thus, this embodiment ofKoyou
`
`is also deficient with regard to the most important dimension of the invention claimed in the '221
`
`patent (i.e., that the width of the cut-link pad is at least ten percent greater than the width of each
`
`of the first and second electrically-conductive lines).
`
`For example, at the time of Koyou's publication, line widths of 1.1-1.3 !lm in the
`
`uppermost layer of metal were not uncommon (see, e.g., p. 10 and p. 11, respectively, of the
`
`Construction Analyses of the Lattice ispLSI2032-180L CPLD [hereinafter the "Lattice
`
`Analysis"] and the Samsung KM44C4000J-7 16 Megabit DRAM [hereinafter the "Samsung
`
`Analysis"], published by Integrated Circuit Engineering, Scottsdale AZ, Report Nos. SCA 9712-
`
`573 and SCA 9311-3001, respectively; submitted herewith as Exhibits A and B). The vias
`
`between the uppermost layer of metal and the next layer of metal there below in these devices had
`
`a width of 1.0 !lm and 1.2 !lm, respectively. Thus, while the uppermost layer of metal in the
`
`Lattice ispLSI2032-180L CPLD was arguably 10% wider than the vias connected thereto (1.1
`
`!lm vs. 1.0 !lm), the uppermost layer of metal in the Samsung KM44C4000J-7 16 Megabit
`
`DRAM was not (i.e., [1.3 - 1.2] I 1.2 = 8.3%). Accordingly, it is not inherent that the width of
`
`Page 4 of26
`
`4
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`the fuse member 20 disclosed in FIG. 3 ofKoyou is at least ten percent greater than the width of
`
`the material filling each of the contact holes 21 a and 21 b.
`
`Furthermore, Koyou does not affirmatively disclose a cut-link pad having substantially
`
`less thermal resistance per unit length than each of the first and second electrically-conductive
`
`lines. It is clear from FIG. 3 of Koyou that the width of the contact holes (vias) 21a and 21 b
`
`(designated as WV below) is much greater than the thickness of the fuse member 20 (designated
`
`as TF below). Based on measurement of the relative dimensions of WV (e.g., about 6.3 mm in
`
`the diagram below) and TF (e.g., about 4.0 mm in the diagram below) in FIG. 3 of Koyou, the
`
`thickness TF of the fuse member 20 is approximately 60% of the width (WV) of the material in
`
`the contact holes 21a and 21b (i.e., TF/WV:::: 0.6).
`
`TF
`
`(Rrm>RTHtl
`r"···· . .-...~-,.·.=-~-.--.~=-- '""·'""'~·••m•~~.~----------~~"4
`... ·
`_
`L\~D}
`I
`20{RnH)
`
`f
`
`wv
`
`Although Koyou does not disclose the width of the fuse member 20 or the width of the
`
`contact holes 21 a and 21 b, based on (i) dimensions for these parameters that were arguably
`
`considered "state of the art" at the time of Koyou's publication (see, e.g., the Lattice Analysis
`
`and the Samsung Analysis), (ii) the approximate ratio of the thickness of the fuse member 20 to
`
`the width of the contact holes 21 a and 21 b as calculated from FIG. 3 of Koyou, and (iii) the
`
`thermal conductivity of the most likely or most commonly used metals for the fuse member 20
`
`Page 5 of26
`
`5
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`and the material in the contact holes 21a and 21b in FIG. 3 of Koyou, the fuse member 20 of
`
`Koyou does not necessarily have less thermal resistance per unit length than the material in the
`
`contact holes 21 a and 21 b, much less substantially less thermal resistance per unit length.
`
`For example, the Lattice Analysis discloses an uppermost metal layer having a width of
`
`1.1 )lm and vias having a width of 1.0 )lm (see the Lattice Analysis, p. 10). Using the via width
`
`from the Lattice Analysis and the ratio of fuse member thickness to via width calculated from
`
`FIG. 3 of Koyou, the thickness of the fuse member 20 is estimated to be 0.6 )lm (i.e., 1.0 )lm x
`
`0.6, or 60%). Koyou discloses that the fuse member 20 may be aluminum and the material
`
`filling the contact holes 21a and 21b may be tungsten (see paragraphs [0016] and [0021] of
`
`Koyou). Accordingly, based on the thermal conductivity of aluminum (i.e., 235 W/m-°K) and of
`
`tungsten (i.e., 170 W/m-°K), the relative thermal conductance per unit length of (1) the fuse
`
`member 20 to (2) the vias in contact holes 21a and 21b in FIG. 3 ofKoyou is 155: 170 (i.e., [1.1
`
`x 0.6 x 235] to [1.0 x 1.0 x 170]). Thus, based on the widths of the uppermost metal layer and
`
`the uppermost via disclosed in the Lattice Analysis and the ratio of the thickness of fuse member
`
`20 to the width of the vias in the contact holes 21a and 21b in FIG. 3 of Koyou, the thermal
`
`conductance per unit length of the fuse member 20 is less than the thermal conductance per unit
`
`length of the material filling the contact holes 21a and 21b (i.e., the thermal resistance per unit
`
`length of the fuse member 20 of FIG. 3 of Koyou is greater than the thermal resistance per
`
`unit length ofthe material filling the contact holes 21a and 21b).
`
`Likewise, using the dimensions of the uppermost metal layer and the uppermost vias in
`
`the Samsung Analysis (i.e., 1.3 )lm and 1.2 )lm respectively; seep. 11 of the Samsung Analysis),
`
`the relative thermal conductance per unit length of the fuse member 20 to the material filling the
`
`contact holes 21a and 21b in FIG. 3 ofKoyou is 220: 245 (i.e., [1.3 x (1.2 x 0.6) x 235] to [1.2 x
`
`1.2 x 170]). Thus, based on the dimensions disclosed in the Samsung Analysis, the thermal
`
`resistance per unit length of the fuse member 20 is greater than the thermal resistance per unit
`
`length of the material filling the contact holes 21 a and 21 b. Therefore, it cannot be said that the
`
`thermal resistance per unit length of the fuse member 20 in FIG. 3 of Koyou is necessarily less
`
`than the thermal resistance per unit length of the material in the contact holes 21 a and 21 b, much
`
`Page 6 of26
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`6
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`less substantially less than the thermal resistance per unit length of the material in the contact
`
`holes 21a and 21b. Thus, even though Koyou discloses that the material filling each of the
`
`contact holes 21 a and 21 b has a higher thermal resistance than the fuse member 20 (paragraph
`
`[0022]), it is not necessarily true that the material filling each of the contact holes 21 a and 21 b
`
`has a higher thermal resistance per unit length than the fuse member 20, because the ratio of (i)
`
`the cross-sectional area of the material filling each of the contact holes 21a and 21 b to (ii) the
`
`cross-sectional area of the fuse member 20 may be greater than the ratio of (i') the thermal
`
`conductance of the fuse member 20 to (ii') the thermal conductance of the material filling each of
`
`the contact holes 21a and 21b. Instead, based on structures and dimensions that were arguably
`
`considered "state of the art" at the time of Koyou's publication, the material filling the contact
`
`holes 21 a and 21 b may have had a lower thermal resistance per unit length then the fuse member
`
`20.
`
`To convert the fuse of FIG. 3 of Koyou into one that necessarily has a pad with
`
`substantially less thermal resistance per unit length than each of the first and second electrically(cid:173)
`
`conductive lines conductively bonded thereto (and thus arrive at the invention of Claim 3 of the
`
`'221 patent), one must increase the width and/or the thickness of the fuse member 20 until the
`
`ratio of the cross-sectional area of the vias 21 a and 21 b to the cross-sectional area of the fuse
`
`member 20 is substantially less than the ratio of the thermal conductances of the corresponding
`
`materials. Both of these modifications are contrary to the wisdom in the art. (Decreasing the
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`width of the vias 21 a and 21 b of Koyou is generally considered to be not viable or feasible, and
`
`perhaps not possible, because vias generally have the smallest feature size of any patterned
`
`
`structure in a particular layer of metallization in an integrated circuit1, and the common wisdom
`
`in the art is to keep via sizes in a particular layer of metallization constant across a wafer to
`
`ensure consistent etching of the via holes.)
`
`1 Patent Owners' undersigned representatives understand that decreasing the via size could necessitate the use of
`higher-resolution photolithography equipment, which is generally reserved for those structures that require higher
`resolution (e.g., transistor gates, transistor isolation structures, contacts to the silicon substrate, etc.). Use of higher(cid:173)
`resolution photolithography equipment for patterning additional layers in an integrated circuit causes manufacturing
`bottlenecks (e.g., if additional equipment is not purchased), lower throughput, lower yields, increased costs (e.g., if
`additional equipment is purchased or if the relatively expensive high-resolution photolithography equipment is
`used), etc.
`
`Page 7 of26
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`7
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`For example, one of ordinary skill in the art would have at least two compelling reasons
`
`not to increase the width of the fuse member 20. First, as recognized by Gordon Moore as far
`
`back as the mid-1960's, (see Moore, Electronics, Vol. 38, No. 8, April 19, 1965; submitted
`
`herewith as Exhibit C), the art has continuously made device dimensions smaller, not larger. For
`
`example, Dr. Moore stated in 1965 that complexity for minimum component costs has increased
`
`at a rate of roughly a factor of two per year, and that over the longer term, there is no reason to
`
`believe this rate will not remain nearly constant for at least 10 years (see Moore, second page,
`
`right-hand column, first full paragraph). The trend identified by Dr. Moore (generally known in
`
`the art as "Moore's Law") has continued for more than half a century and is expected to continue
`
`until 2015 or 2020 or later (see Myhrvold, "Moore's Law Corollary: Pixel Power," New York
`
`Times, June 7, 2006; submitted herewith as Exhibit D). Moore's Law describes a long-term trend
`
`in the history of computing hardware, in which the number of transistors that can be placed
`
`inexpensively on an
`
`integrated circuit doubles approximately every
`
`two years
`
`(see
`
`http://wvvvv:vvikipedia.org/, "Moore's_law," submitted herewith as Exhibit E). In order for such
`
`trends to exist, the accepted wisdom in the art over this period of time has been to decrease the
`
`dimensions of structures in integrated circuits.
`
`Increasing the width of the fuse member 20
`
`would therefore proceed contrary to accepted wisdom in the art.
`
`Second, for a given laser with a given spot size (e.g., as determined using the full-width
`
`half-max method; see, for example, col. 4, 1. 61-col. 5, 1. 3 of the '221 patent), increasing the
`
`width of the fuse member 20 will increase the probability that some part of the fuse member 20
`
`may not receive sufficient energy for complete fuse ablation (see also paragraph [0004] of
`
`Koyou, although Koyou demonstrates this phenomenon using the length of fuse member 20).
`
`Thus, there are at least two reasons why one of ordinary skill in the art would not increase the
`
`width of the fuse member 20 to arrive at the present invention.
`
`Also, one of ordinary skill in the art would not increase the thickness of the fuse member
`
`20 to form a pad with substantially less thermal resistance per unit length than each of the first
`
`and second electrically-conductive lines conductively bonded thereto, and thus arrive at the
`
`invention of Claim 3 of the '221 patent. Koyou teaches that where the volume of the fuse
`
`Page 8 of26
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`8
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`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
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`member is large, it has a large thermal capacity (see paragraph [0007], entitled "Problem Solved
`
`by the Invention," of Koyou). Because of this, the larger-volume fuse member has a problem in
`
`that its use is limited to a laser beam with a high illumination energy (Ibid.). The object of
`
`Koyou's disclosure is to be able to disconnect a fuse member thoroughly and easily, using a laser
`
`beam with a relatively small amount of energy and without adding any special manufacturing
`
`processes (such as fabricating a protruding portion in the insulating layer below the fuse
`
`member; see paragraphs [0007] and [0008] of Koyou).
`
`Increasing the thickness of the fuse
`
`member 20 would increase the volume and the thermal capacity of the fuse member, and thus
`
`require one to apply more energy to the fuse member 20 to completely disconnect it. This runs
`
`contrary to the teachings of Koyou and could defeat the purpose of Koyou's disclosure. Thus,
`
`one of ordinary skill in the art would not increase the thickness (or, as explained above, the
`
`width) of the fuse member 20 in FIG. 3 of Koyou in the manner necessary to arrive at the
`
`invention defined in Claim 3 of the '221 patent.
`
`Furthermore, as taught by the '221 patent, the difference between a fuse that, by design,
`
`includes a thermal bottleneck at the interface between the fuse pad and the conductive lines
`
`thereto (and thereby retains and builds up heat energy during laser irradiation at a maximum rate)
`
`and one that allows some part of the heat energy to be withdrawn at a maximum rate during laser
`
`irradiation is substantial, because a cut-link pad can be ablated more efficiently by maximizing
`
`the absorption of laser energy in the pad and minimizing the transfer of that energy away from
`
`the pad (see col. 4, 11. 51-60 of the '221 patent).
`
`Fuse structures as recited in Claim 3 of the '221 patent retain thermal energy at the site of
`
`the cut-link more effectively because the conductive lines have a substantially higher thermal
`
`resistance per unit length than the cut-link pad, thereby restricting the dissipative heat transfer
`
`into the conductive lines, and improving the probability of a fuse being successfully cut by laser
`
`irradiation. Even a small change in the probability of successful fuse cutting during the laser
`
`repair process can have a profound effect on the yield of certain devices containing such fuses,
`
`which in tum can rather significantly impact the revenue and profitability of manufacturers
`
`possessing technology that more successfully cuts the fuses.
`
`Page 9 of26
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`9
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`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`For example, a typical DRAM wafer contains 10 million fuses (see Andy E. Hooper, et
`
`al., "Advances
`
`in Laser Technologies for Semiconductor Memory Yield and Repair
`
`Applications," Electro-Scientific Industries, Portland, OR; p. 3, sixth paragraph; submitted
`
`herewith as Exhibit F). Of these 10 million fuses, in a typical laser repair process, more than 2
`
`million (> 20%) of the fuses may need cutting (see Paul Marsden, "Precision Beam Positioning
`
`in Electronics Manufacturing," The Laser User, Issue 57, Winter 2009 [hereinafter "Precision
`
`Beam Positioning"]; p. 7, the paragraph entitled "Laser Memory Repair"; submitted herewith as
`
`Exhibit G). Thus, in a DRAM wafer containing 2000 die (i.e., where each dies contains
`
`10,000,000 I 2000 = 5000 fuses/die), each die to be repaired may have about 1000 fuses (i.e.,
`
`5000 x 0.2, or 20%) that need to be cut in a typical memory repair process. (Although> 20% of
`
`the fuses are cut in a typical process, 20% was chosen for purposes of simplifying the
`
`calculation[s] and/or estimation[s] herein; the actual effect on revenue and profitability may be
`
`greater than that calculated and/or estimated herein.)
`
`If the process for cutting a fuse designed m accordance with FIG. 3 of Koyou is
`
`successful 99.97% of the time, the laser repair yield for the DRAM devices described in the
`preceding paragraph would be 74.08% (i.e., 0.9997 1000
`
`). Patentees' undersigned representatives
`
`believe that such yields were not uncommon in the DRAM industry after the filing date of the
`
`'221 patent, but prior to the publication of Exhibits F and G, and may be representative of yields
`
`obtained using the fuse design of FIG. 3 ofKoyou. It is believed that a yield of99.97% may be
`
`optimistic for repair of an individual fuse designed according to FIG. 3 of Koyou and having the
`
`dimensions described above, perhaps even when the fuse member 20 has a width more than 10%
`
`greater than the width of the vias 21 a and 21 b.
`
`However, if the percentage of fuses successfully cut is increased by just 0.02% (i.e., to
`
`99.99%) by the process of Claim 3 of the '221 patent, the yield for such devices increases
`significantly, to 90.48% (i.e., 0.9999 1000
`
`). This translates to an increase in the laser repair yield
`
`of (90.48% - 74.08%) = 16.4% for the DRAM die described in the preceding two paragraphs.
`
`Patentees' undersigned representatives also understand and believe that the method recited in the
`
`Page 10 of26
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`10
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`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`present Claim 3 is capable of producing such a success rate (i.e., 99.99%) for the laser cutting of
`
`a single fuse.
`
`In the DRAM industry, less than 10% of DRAMs do not need repair (see Precision Beam
`
`Positioning [Exhibit G], p. 7, the paragraph entitled "Laser Memory Repair"). Therefore, the
`
`gross number of die per wafer to be repaired in our example is (2000 x [1 - 0.1]) = 1800.
`
`(Although< 10% of the DRAMs do not need repair in a typical DRAM manufacturing process,
`
`10% was chosen for purposes of simplifying the calculation I estimation herein; the actual effect
`
`on revenue and profitability is expected to be greater than that calculated and/or estimated
`
`herein.) The 16.4% increase in the laser repair yield estimated in the preceding paragraph
`
`equates to an additional (1800 x 0.164) = 295 die per wafer on average repaired as a result of the
`
`repmr process.
`
`At a price of roughly $1.00 per die (see DRAM eXchange, DRAM Spot Price, Items
`
`DDR, DDR2 and DDR3, available at http://vvwvv.dramexchange.com [last visited Aug. 6, 2011];
`
`attached hereto as Exhibit H), a DRAM manufacturer having a production capacity of 80,000
`
`wafers per month can realize an increase in revenue due to the higher yield of the improved fuse
`
`cutting process of the '221 patent of approximately (295 die/wafer x $1.00/die x 80,000
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`wafers/month x 12 months/year)= $280,000,000 per year. Thus, a very small increase (0.02%)
`
`in the probability of successful fuse cutting, similar to that which may be provided by the process
`
`recited in Claim 3 of the '221 patent relative to an otherwise identical process using the fuse
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`design disclosed in FIG. 3 of Koyou, can dramatically increase the annual revenue of a DRAM
`
`manufacturer practicing such a process. Given that the overhead costs for manufacturing bad die
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`are essentially the same as for good die, the impact on profitability of the DRAM manufacturer
`
`practicing the process of Claim 3 of the '221 patent is expected to be even greater.
`
`As demonstrated above, Koyou fails to (1) inherently disclose that the width of the cut(cid:173)
`
`link pad is at least ten percent greater than the width of each of the first and second electrically(cid:173)
`
`conductive lines, and (2) teach or suggest a cut-link pad that has substantially less thermal
`
`resistance per unit length than each of the first and second electrically-conductive lines
`
`conductively bonded thereto. Thus, Claim 3 is patentable and/or enforceable over Koyou.
`
`Page 11 of26
`
`11
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`Claim 4:
`
`Claim 4 depends from Claim 3 and adds the limitation that the laser beam extends across
`
`the entirety of the cut-link pad when the laser is directed upon the cut-link pad (see the
`
`Amendment).
`
`Reexamination of Claim 4 has been requested in view of Koyou.
`
`The discussion of the patentability of Claim 3 in the Patent Owners' Statement above is
`
`incorporated herein by reference. For at least the same reasons as Claim 3, Claim 4 is not
`
`anticipated or rendered obvious in view ofKoyou.
`
`Claims 6-7:
`
`Claims 6-7 have been amended to depend from Claim 3 (see the Amendment). Claim 6
`
`adds the limitation that the width of the cut-link pad is at least twenty-five percent greater than
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`the width of each of the first and second electrically-conductive lines. Claim 7 adds the
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`limitation that the width of the cut-link pad is at least fifty percent greater than the width of each
`
`of the first and second electrically-conductive lines.
`
`Reexamination of Claims 6-7 has been requested in view of (1) Nishimura et al., U.S.
`
`Pat. No. 5,872,389 (hereinafter "Nishimura"), and (2) Wada et al., Japan Pat. Appl. Pub. No. 6-
`
`244285, published Sep. 2, 1994 (hereinafter "Wada"). Claims 6-7 are not anticipated or rendered
`
`obvious in view ofNishimura and Wada, either alone or in combination, because Nishimura and
`
`Wada do not disclose or suggest that the electrically-conductive cut-link pad has an inner surface
`
`facing the substrate and an opposing outer surface facing away from the substrate, or that the
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`first and second electrically-conductive lines extend from the inner surface into the substrate, as
`
`recited in Claim 3 of the '221 patent.
`
`Page 12 of26
`
`12
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`1.
`
`Discussion ofNishimura
`
`Nishimura discloses a two dimensional fuse structure, not the three-dimensional fuse
`
`structure recited in Claim 3 ofthe '221 patent (see the Amendment and FIGS. 10-11 of the '221
`
`patent). Nishimura discloses that "fuse layer 2 has a first portion 2a having [a] relatively large
`
`planar width WI and a second portion 2b having [a] relatively small planar width W2. A pair of
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`second portions 2b are [sic] provided on both sides of the first portion 2a ... the planar width WI
`
`of the first portion 2a is larger than the planar width of the second portion 2b" (see col. 6, 11. 28-
`
`32 and 39-40, and FIGS. 3 and 4 of Nishimura). Consequently, Nishimura fails to disclose or
`
`suggest that the electrically-conductive cut-link pad has an inner surface facing the substrate and
`
`an opposing outer surface facing away from the substrate, or that the first and second
`
`electrically-conductive lines extend from the inner surface into the substrate.
`
`2.
`
`Discussion ofWada
`
`Similar to Nishimura, Wada discloses a two-dimensional fuse structure, rather than the
`
`three-dimensional fuse structure as recited in Claim 3 of the '221 patent (see the Amendment and
`
`FIGS. 10-11 of the '221 patent). Wada discloses that "redundancy fuse 1 is formed of a fusing
`
`portion la and non-fusing portion[ ]s [sic] lb ... The fusing portion la is continuously provided
`
`between the non-fusing portions 1 b on both sides thereof so as to overlap an irradiation region 4
`
`of a laser beam ... A width of the fusing portion la is set to be larger than a width of the non(cid:173)
`
`fusing portions lb ... " (see paragraph [0010] and FIG. 1 of Wada). Wada also discloses "a
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`redundancy fuse formed of a fusing portion positioned in the center, within an irradiation region
`
`of the energy beam, and a non-fusing portion within an irradiation region of the energy beam
`
`provided on both ends ofthe fusing region ... " (see paragraph [0007] ofWada). Consequently,
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`Wada also fails to disclose or suggest that the electrically-conductive cut-link pad has an inner
`
`surface facing the substrate and an opposing outer surface facing away from the substrate, or that
`
`the first and second electrically-conductive lines extend from the inner surface into the substrate.
`
`Page 13 of26
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`13
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`

`

`Atty. Docket No. MIT-7581L-RX1
`U.S. Patent No.: 6,057,221
`
`Control No.: 90/011,607
`
`Thus, Claims 6-7 are patentable and/or enforceable in view of Nishimura and Wada,
`
`alone or in combination.
`
`The patentability of Claim 3 in view of Koyou as discussed in the Patent Owners'
`
`Statement above is also relevant here, and is incorporated herein by reference.
`
`Additionally, Koyou is silent with regard to the relative widths of the fuse member 1, 10
`
`or 20 and the interconnect lines 3a-3b, 11a-11 b, or 22a-22b, and thus, fails to disclose not only
`
`that the width of the cut-link pad is at least ten percent greater that the width of the first and
`
`second electrically-conductive lines, but also that the width of the cut-link pad is twenty-five
`
`percent greater or fifty percent greater than the width of the electrically-conductive lines. Thus,
`
`for these reasons and for the same reasons as Claim 3, Claims 6-7 are patentable and/or
`
`enforceable over Koyou.
`
`Claim 8:
`
`Claim 8 depends from Claim 7 (which, as amended, depends from Claim 3). Claim 8
`
`adds the limitation that the cut-link pad comprises a composition substantially identical to the
`
`composition of the first and second electrically-conductive lines (see the Amendment).
`
`Reexamination of Claim 8 has been requested in view of (1) Nishimura and (2) Wada.
`
`The discussion of the patentability of Claims 6-7 in the Patent Owners' Statement above is
`
`incorporated by reference. For at least the same reasons as Claims 6-7, Claim 8 is patentable
`
`and/or enforceable in view ofNishimura and Wada, alone or in combination.
`
`The patentability of