USOO716446OB2
`
`(12) United States Patent
`Hagiwara
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 7,164,460 B2
`Jan. 16, 2007
`
`(54) MOUNTING STRUCTURE FOR
`SEMICONDUCTOR DEVICE,
`ELECTRO-OPTICAL DEVICE, AND
`ELECTRONIC APPARATUS
`
`6,356,333 B1*
`2002fOO60767 A1*
`
`3/2002 Uchiyama ................... 349,149
`5/2002 Muramatsu et al. ........ 349,139
`
`FOREIGN PATENT DOCUMENTS
`
`(75) Inventor: Takeshi Hagiwara, Matsumoto (JP)
`(73) Assignee: Seiko Epson Corporation (JP)
`
`(*) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 182 days.
`(21) Appl. No.: 09/790,985
`
`CN
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`
`1235375
`52-72567
`60-146225
`60-146225
`61-149348
`61-215528
`05-2101.07
`6-4606
`
`11, 1999
`6, 1977
`* 1 1985
`8, 1985
`9, 1986
`* 9/1986
`8, 1993
`2, 1994
`
`(22) Filed:
`
`Feb. 22, 2001
`
`(65)
`
`Prior Publication Data
`US 2001/OO33355 A1
`Oct. 25, 2001
`
`Foreign Application Priority Data
`(30)
`Feb. 24, 2000 (JP)
`............................. 2000-048041
`
`(51) Int. Cl.
`(2006.01)
`GO2F I/345
`(2006.01)
`HOIL 2L/00
`(52) U.S. Cl. ...................... 349/149; 34.9/152; 34.9/151:
`438/30
`(58) Field of Classification Search ........ 349/149-152,
`34.9/158, 139; 438/30, 25, 26
`See application file for complete search history.
`References Cited
`
`(56)
`
`U.S. PATENT DOCUMENTS
`
`1/1997 Kawaguchi et al. ........ 345,206
`5,592,199 A *
`5,768,105 A * 6/1998 Aota et al. .................. 361/777
`5,914,763. A
`6/1999 Fujii et al.
`5.959,713 A * 9/1999 Kobayashi .................. 349,192
`6,052,170 A * 4/2000 Kobayashi .................. 349,149
`6,151,091 A * 1 1/2000 Muramatsu ................. 349,149
`6,265,770 B1
`7/2001 Uchiyama
`6,297.868 B1 * 10/2001 Takenaka et al. ........... 349,151
`6,300,997 B1 * 10/2001 Saito et al. ................. 349,149
`
`
`
`(Continued)
`OTHER PUBLICATIONS
`Korean Notice of Preliminary Rejection.
`(Continued)
`Primary Examiner Andrew Schechter
`Assistant Examiner Mike Qi
`(74) Attorney, Agent, or Firm Harness, Dickey & Pierce,
`P.L.C.
`
`(57)
`
`ABSTRACT
`
`In an IC mounting region 70 of a substrate 20 constituting
`a liquid crystal device, first terminals 91A, 91B, and 91C are
`divided into a plurality of terminals 911A, 912A, 913A,
`914A, 921B, 922B, 921C, and 922C by slits 96 formed of
`portions where an ITO film forming wiring patterns 91 and
`the first terminals 91 is not formed. For this reason, when the
`first terminals 91 and first electrodes 71 are electrically and
`mechanically connected by an anisotropic conductive film,
`a resin component contained in the anisotropic conductive
`film fixedly bonds a driving IC 7 to the second transparent
`substrate 20 while it enters the slits 96. Since the area of the
`resin component 61 of the anisotropic conductive film in
`contact with the first terminals 91 is large, fixing strength of
`the IC 7 is increased.
`
`28 Claims, 10 Drawing Sheets
`
`Page 1 of 20
`
`Tianma Exhibit 1012
`
`

`

`US 7,164.460 B2
`Page 2
`
`FOREIGN PATENT DOCUMENTS
`
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`
`06-051349
`06-333.662
`O7-225392
`08-045381
`8-201833
`08-201833
`08-313925
`09-260579
`
`2, 1994
`12/1994
`8, 1995
`2, 1996
`* 8/1996
`8, 1996
`11, 1996
`10, 1997
`
`JP
`JP
`JP
`
`10-2092O2
`11-145373
`11-284.030
`
`8, 1998
`5, 1999
`10, 1999
`
`OTHER PUBLICATIONS
`Examination Report from corresponding Japanese Application.
`Communication from Chinese Patent Office regarding counterpart
`application
`pp
`* cited by examiner
`
`Page 2 of 20
`
`

`

`U.S. Patent
`U.S. Patent
`
`Jan. 16, 2007
`Jan.16,2007
`
`Sheet 1 of 10
`Sheetl,of10
`
`US 7,164,460 B2
`US 7,164,460 B2
`
`FIG. 1
`FIG. 1
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`
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`Page 3 of 20
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`Page 3 of 20
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`

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`U.S. Patent
`U.S. Patent
`
`Jan. 16, 2007
`Jan.16,2007
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`Sheet 2 of 10
`Sheet2 of10
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`US 7,164,460 B2
`US 7,164,460 B2
`
`FIG. 2
`FIG. 2
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`Page 4 of 20
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`Page 4 of 20
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`U.S. Patent
`U.S. Patent
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`Jan. 16, 2007
`Jan.16,2007
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`Sheet 3 of 10
`Sheet3 0f10
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`US 7,164,460 B2
`US 7,164,460 B2
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`
`
`’i’’””””"’f”¢fili””f’f””"d”’tflI1mm::i§§
`
`.uflmfwliii.fin
`No.i!!!!!!!…No.
`
`on
`
`
`
`
`
`m.0.“—
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`Page 5 of 20
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`Page 5 of 20
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`U.S. Patent
`U.S. Patent
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`Jan. 16, 2007
`Jan. 16, 2007
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`Sheet 4 of 10
`Sheet 4 0f 10
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`US 7,164,460 B2
`US 7,164,460 B2
`
`FIG. 4
`FIG. 4
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`Page 6 of 20
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`Page 6 of 20
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`U.S. Patent
`U.S. Patent
`
`Jan. 16, 2007
`Jan. 16, 2007
`
`Sheet S of 10
`Sheet 5 0f 10
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`US 7,164,460 B2
`US 7,164,460 B2
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`FIG. 5
`FIG. 5
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`Page 7 of 20
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`Page 7 of 20
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`

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`U.S. Patent
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`Jan. 16, 2007
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`Sheet 6 0f 10
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`US 7,164,460 B2
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`FIG. 6(A)
`
`
`
`
`
`\\\\\\\ \\‘“§§'\’\\\“‘{{\'§\\\\\ \\\\\\\‘ \\\\\\“\.\\\\\\\\\\ \\\\\\\\\\\
`
`Willll/JMWIIIWJ[WW/IIII/[III :— 6
`
`91,910
`
`9110’
`
`9120
`
`
`
`
`“3‘“\mm
`
`
`
`\\\\\\\l<\\\\\l\\\\l\\\\\\l\\\\\‘l\\\\\\‘l\\\.\\—\\\\\\I\\\\\
`- ”WWII/”WWI,
`
`
` 20
`9123/
`9113
`914A
`
`
`
`
`91,91A
`91,9113
`FIG. 6(B)
`
`
`\\\\\\\\VV\VW\\
`
`
`
`\\\\\\\})\>\i\\\\”i\\\\t\\\1\\\\\l\\\\\\\l\\\I\\rZ/\\\\\N\'\\
`
`\\\\\\\1\\\\\\m\\\\1\\\\\\m\\\\\\\\\\\\|\\\\\h-‘’.'m\\1\\\\<\<'
`
`
`”WWI/WWW;
`
`9120
`9110’
`914A
`912A1913A
`911A
`
`
`91,91A
`
`91,910
`
`
`FIG. 6(6)
`
`’ Jll/l
`‘ K/p
`\\\V\‘\\~‘\‘~‘m\\\\\\\\\\\\
`
`
`
`
`\\\\\‘§i\\\\\\\2“\\\"\“‘{\\'\\\\\.\_\\\\\\\\is\\\\\\\‘f\\\_\\\\//\\\\\’\\\\
`\\\\\\5\\\\\‘\\-§§§\\\§R{\\\\\\V\\\\\\p§\\\\\m\\\\\\
`/\\\\\\\\‘i\\\\\\\
`1///ll/fl/lllllflfl/W/l/Al.
`
`
`
`9128
`9118
`913A 914A
`911111912111
`
`
`91,91A
`
`91,9113
`
`9110
`
`Page 8 of 20
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`Page 8 of 20
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`

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`U.S. Patent
`
`Jan. 16, 2007
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`Sheet 7 of 10
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`US 7,164,460 B2
`
`FIG. 7
`
`921A-1922A-1923A
`
`
`
`
`
`97
`92,92A
`921 B-1922B-1923B
`92,92B
`92,92D/ 97
`921 C-1 922C
`N-N-1
`92,92C
`
`9,9D
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`Page 9 of 20
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`

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`U.S. Patent
`
`Jan. 16, 2007
`
`Sheet 8 of 10
`
`US 7,164.460 B2
`
`FIG. 8(A)
`
`
`
`FIG. 8(B)
`
`FIG. 8(C)
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`
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`1204
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`Page 10 of 20
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`U.S. Patent
`
`Jan. 16, 2007
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`Sheet 9 of 10
`
`US 7,164,460 B2
`
`FIG. 9
`PRIOR ART
`
`
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`Page 11 of 20
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`

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`U.S. Patent
`
`Jan. 16, 2007
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`Sheet 10 0f 10
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`US 7,164,460 B2
`
`FIG. 10(A)
`
`
`
`R\\\ R\\\Rx‘“R\\\“VRR R\\\ R\\R R\\\
`x\\\\\\\\“ R\\R‘
`
`
`\\\\\\\\\\\\\\\\'\\\\\\\\V\\
`I'I/IMJJIMImflA'IIIIWI”WWII-6
`R\\\R\\\\\\\\\\\\\\\\\\‘I\\\\\\\\\\\\\IR\R_x\\\\\RRV
`
`
`llmll/IIII/I/IYI/I/l/l’l-
`91, 91A
`91 ,91B
`91, 910
`91, 91C
`
` 20
`
`FIG. 10(B)
`
`
`
`\\\\V\\\\\\\\\\\\\\\\\\\\
`
`
`
`
`R\\\l\\\xx\\l\\\\“Rl\\\\\\RlR\\I\\\RIR\\\R\\\IR\
`RRRRR\RRRR \IRRxR\IRR‘éZRR‘RR
`Ill/IIIIIIII””\I\.III’I)IIAIII)”MIII
`”ll/I'Jl’."
`
`
`ll/IMI/J/I/I/I/I’Ill/Il
`
`
`91, 91A
`
`
`FIG. 10(0)
`
`
`
`
`\\\‘\\\\\.~.,\\\\\\\\\\\
`
`
`R\\\iRR“RRR'RRF\\\‘R\'\\\.fl/R\\\'R\\\\V
`R\\\\\\\\\\\\\\\\\\\\\\\\\\\\!R\\;\\\\\ /\\x‘\\\\\\
`
`
`///J/////I///I/////I////////l
`
`9191B /9191D 91,910
`9191A
`
`62
`
`61
`
`PRIOR ART
`
`Page 12 of 20
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`Page 12 of 20
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`

`

`US 7,164,460 B2
`
`1.
`MOUNTING STRUCTURE FOR
`SEMICONDUCTOR DEVICE,
`ELECTRO-OPTICAL DEVICE, AND
`ELECTRONIC APPARATUS
`
`BACKGROUND OF THE INVENTION
`
`2
`In FIG. 9, the IC mounting region 70 and the flexible
`wiring board connecting region 80 are connected by wiring
`patterns 9 formed simultaneously with formation of the
`driving electrode patterns 25. The ends of the wiring patterns
`9 placed in the IC mounting region 70 form multiple first
`terminals 91 (a first terminal group), and are connected to
`multiple first electrodes 71 (a first electrode group) formed
`on the active surface of the driving IC 7. The ends of the
`wiring patterns 9 placed in the flexible wiring board con
`necting region 80 form multiple second terminals 92 (a
`second terminal group), and are connected to a second
`electrode group (not shown) formed on the flexible wiring
`board 8 (see FIGS. 1, 2, and 3).
`Among the plural wiring patterns 9 (9A, 9B, 9C, and 9D),
`the wiring patterns 9A, 9B, and 9C for supplying voltages,
`Such as a ground potential VSS and a high-voltage potential
`Vdd, from the flexible wiring board 8 to the driving IC 7 are
`provided, in the IC mounting region 70, with first terminals
`91A, 91B, and 91C which are solid and even wider than a
`first terminal 91D formed at the end of the wiring pattern 9D.
`Some of the first electrodes 71 of the driving IC 7 are
`collectively and electrically connected to each of the termi
`nals 91A, 91B, and 91C. Similarly, the wiring patterns 9A,
`9B, and 9C are provided, in the flexible wiring board
`connecting region 80, with second terminals 92.A. 92B, and
`92C which are solid and much wider than a second terminal
`92.D formed at the end of the wiring pattern 9D, and some
`of the second electrodes of the flexible wiring board 8 are
`collectively and electrically connected to each of the termi
`nals 92A, 92B, and 92C.
`Since the distance between the adjoining electrodes is
`considerably short, such electrical connections are generally
`made by using an ACF (Anisotropic Conductive Film). In a
`mounting method using the anisotropic conductive film, as
`shown in FIG. 10(A), first, an anisotropic conductive film 6
`is applied to the IC mounting region 70, or a sheet-like
`anisotropic conductive film 6 is placed on the IC mounting
`region 70. Subsequently, the first electrodes 71 of the driving
`IC 7 are aligned with the first terminals 91 formed on the
`second transparent substrate 20. In this state, the driving IC
`7 is heated and press-bonded to the second transparent
`substrate 20 by a head 60, as shown in FIG. 10(B). As a
`result, a resin component 61 contained in the anisotropic
`conductive film 6 is melted, and conductive particles 62
`contained in the anisotropic conductive film 6 are crushed
`between the first terminals 91 and the first electrodes 71, as
`shown in FIG. 10(C). For this reason, the first terminals 91
`and the first electrodes 71 are electrically connected via the
`conductive particles 62, and the driving IC 7 is fixed on the
`second transparent substrate 20 in a state in which the resin
`component 61 contained in the anisotropic conductive film
`6 is hardened.
`As shown in FIG. 9, the second transparent substrate 20
`is provided with the electrode patterns 25 for supplying
`signals output from the driving IC 7 to pixels. The ends of
`the electrode patterns 25 placed in the IC mounting region
`70 form multiple third terminals 93 (a third terminal group).
`Multiple third electrodes 73 (a third electrode group) formed
`on the active surface of the driving IC 7 are electrically
`connected to the third terminals 93. Since the electrical
`connection in this portion is made simultaneously with the
`process described with reference to FIG. 9 and the manner
`thereof is similar to that described with reference to FIG. 9,
`description thereof is omitted. A method for electrically
`connecting the flexible wiring board 8 to the flexible wiring
`board connecting region 80 of the second transparent Sub
`
`1. Technical Field of the Invention
`The present invention relates to a mounting structure for
`a semiconductor device (hereinafter referred to as an “IC),
`an electro-optical device using the mounting structure, and
`an electronic apparatus using the electro-optical device as a
`display. More particularly, the present invention relates to a
`terminal structure in a mounting structure, using an aniso
`tropic conductive film.
`2. Description of the Related Art
`Liquid crystal devices are typical of electro-optical
`devices. For example, in a passive matrix liquid crystal
`device 1 shown in FIGS. 1, 2, and 3 among the liquid crystal
`devices, a first transparent Substrate 10 made of glass or the
`like and a second transparent substrate 20 similarly made of
`glass or the like are fixedly bonded with a predetermined
`clearance therebetween so as to hold a sealing material 30
`therebetween. Between the first transparent substrate 10 and
`the second transparent substrate 20, liquid crystal 5 is sealed
`in a liquid crystal sealing region 300 enclosed by the sealing
`material 30. The first transparent substrate 10 and the second
`transparent substrate 20 are provided, respectively, with
`electrode patterns 15 and 25 for driving which extend in
`orthogonal directions so as to apply Voltage to the liquid
`crystal.
`In the liquid crystal device, since the second transparent
`substrate 20 is larger than the first transparent substrate 10,
`a portion thereof protrudes from the edge of the first trans
`parent substrate 10. The protruding portion 200 of the
`second transparent Substrate 20 has an IC mounting region
`70, where a driving IC (semiconductor device) 7 for out
`putting driving signals to the electrode patterns 15 and 25 is
`mounted, and a flexible wiring board connecting region 80
`that connects a flexible wiring board 8 for Supplying various
`signals and voltages to the driving IC 70.
`The electrode patterns 25 formed on the second transpar
`ent substrate 20 extend from the IC mounting region 70, and
`signals are directly supplied thereto from the driving IC 7
`mounted in the IC mounting region 70. In contrast, the
`electrode patterns 15 formed on the first transparent sub
`strate 10 are electrically connected to the ends of wiring
`patterns 94 for conduction between the substrates, which
`extend from both ends of the IC mounting region 70 of the
`second transparent Substrate 20, via an intersubstrate con
`ducting material contained in the sealing material 30 when
`the first transparent substrate 10 and the second transparent
`substrate 20 are bonded by the sealing material 30.
`In this example, the IC mounting region 70 and the
`flexible wiring board connecting region 80 are generally
`structured as shown in FIG. 9 as a partly enlarged view. In
`the IC mounting region 70, an electrical connection is made
`between the driving IC 7 and the wiring patterns 25 and an
`electrical connection is made between the driving IC 7 and
`the intersubstrate conducting wiring patterns 94 for conduc
`tion between the substrates. Since the connections are basi
`cally the same in structure, FIG. 9 shows only the electrical
`connection between the driving IC 7 and the wiring patterns
`25 in the IC mounting region 70. Illustration and description
`of the electrical connection between the driving IC 7 and the
`intersubstrate conducting wiring patterns 94 are omitted.
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`US 7,164,460 B2
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`3
`strate 20 is nearly similar to that described with reference to
`FIG. 9. Therefore, description thereof is also omitted.
`In Such a mounting structure using the anisotropic con
`ductive film 6, mechanical strength of the mounting section
`is governed by the adhesive force of the resin component 61
`contained in the anisotropic conductive film 6. In the con
`ventional mounting structure, when the first terminals 91
`formed on the second transparent substrate 20 and the first
`electrodes 71 formed on the driving IC 7 are reduced in size,
`the mechanical strength therebetween is significantly
`decreased.
`With such problems in view, an object of the present
`invention is to provide an IC mounting structure in which
`mechanical strength of a mounting section using an aniso
`tropic conductive film can be increased by improving the
`structure of terminals for IC mounting, an electro-optical
`device, and an electronic apparatus.
`
`SUMMARY OF THE INVENTION
`
`In order to solve the above problems, the present inven
`tion provides a semiconductor device mounting structure for
`mounting a semiconductor device on a semiconductor
`device mounting region of a Substrate, wherein a group of
`first terminals is provided in the semiconductor device
`mounting region of the Substrate, the semiconductor device
`has a group of first electrodes to be electrically connected to
`the group of first terminals by an anisotropic conductive
`film, and the group of first terminals includes at least a group
`of divided terminals divided by a slit formed of a portion
`where a conductive film forming the group of first terminals
`is not provided.
`In the present invention, since the first terminals are
`divided into a plurality of terminals (divided terminals) in a
`comb-like form by the slits, they have pits and projections
`formed by the slits. For this reason, when the first terminals
`and the first electrodes are electrically and mechanically
`connected by an anisotropic conductive film, the resin
`component contained in the anisotropic conductive film
`fixedly bonds the IC to the substrate while it enters the pits
`(the slits). Consequently, the area of the resin component in
`contact with the first terminals is larger, by the areas of the
`side face portions of the first terminals, than that in the
`conventional mounting structure. Since this Substantially
`increases the contact area, bonding strength of the IC to the
`Substrate is increased.
`In the present invention, for example, predetermined
`electrodes of the group of first electrodes are placed on the
`terminals constituting the group of divided terminals in a
`one-to-one correspondence so as to be electrically connected
`thereto.
`In the present invention, it is preferable that the substrate
`be provided with a flexible wiring board connecting region
`having a group of second terminals, that a group of second
`electrodes on a flexible wiring board be electrically con
`nected to the group of second terminals via an anisotropic
`conductive film, and that the group of first terminals include
`at least a group of divided terminals divided by a slit formed
`of a portions where a conductive film forming the group of
`second terminals is not provided.
`In this way, since the second terminals are also divided in
`a comb-like form into a plurality of terminals (divided
`terminals) by slits in the connecting region between the
`substrate and the flexible wiring board in this aspect, they
`are provided with pits and projections formed by the slits.
`For this reason, when the second terminals and the second
`electrodes are electrically and mechanically connected by an
`
`4
`anisotropic conductive film, a resin component contained in
`the anisotropic conductive film fixedly bonds the flexible
`wiring board to the substrate while it enters the pits (slits).
`Consequently, the area of the resin component in contact
`with the second terminals is increased by the areas of side
`face portions of the second terminals. Since this substan
`tially increases the contact area, bonding strength of the
`flexible wiring board to the substrate is increased.
`In the present invention, for example, predetermined
`electrodes of the group of second electrodes are placed on
`the terminals constituting the group of divided terminals in
`a one-to-one correspondence so as to be electrically con
`nected thereto.
`An IC mounting structure to which the present invention
`is applied is applicable to, for example, an electro-optical
`device. In the electro-optical device, a plurality of electrode
`patterns extend on a Substrate so as to Supply a driving signal
`from an IC mounted on an IC mounting region to pixels.
`Such an electro-optical device may be used as, for example,
`displays of various electronic apparatuses.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view schematically showing the
`external appearance of a liquid crystal device.
`FIG. 2 is a perspective view schematically showing an
`exploded state of the liquid crystal device shown in FIG. 1.
`FIG. 3 is a cross-sectional view of the liquid crystal
`device, taken along line A A' in FIG. 1.
`FIG. 4 is a perspective view showing a state in which a
`driving IC is mounted on an IC mounting region in a liquid
`crystal device according to a first embodiment of the present
`invention.
`FIG. 5 is a perspective view showing a state in which a
`flexible wiring board is connected to a flexible wiring board
`connecting region of a second Substrate in the liquid crystal
`device according to the first embodiment of the present
`invention.
`FIG. 6 is a process sectional view schematically showing
`a state in which the driving IC is mounted on the IC
`mounting region of the second Substrate in the liquid crystal
`device according to the first embodiment of the present
`invention.
`FIG. 7 is a perspective view showing a state in which a
`flexible wiring board is connected to a flexible wiring board
`connecting region of a second Substrate in a liquid crystal
`device according to a second embodiment of the present
`invention.
`FIGS. 8(A), 8(B), and 8(C) are explanatory views of
`electronic apparatuses each having a liquid crystal device to
`which the present invention is applied.
`FIG. 9 is a perspective view showing a state in which a
`driving IC is mounted on an IC mounting region of a second
`Substrate in a conventional liquid crystal device.
`FIG. 10 is a process sectional view schematically showing
`a state in which the driving IC is mounted on the IC
`mounting region of the second Substrate in the conventional
`liquid crystal device.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`Embodiments of the present invention will be described
`with reference to the attached drawings. While the present
`invention has various applications, embodiments, which will
`be described below, respectively show cases in which the
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`US 7,164,460 B2
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`10
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`25
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`5
`present invention is applied to a liquid crystal device that is
`most typical of electro-optical devices.
`FIG. 1 is a perspective view schematically showing the
`external appearance of a liquid crystal according to this
`embodiment, FIG. 2 is a perspective view schematically 5
`showing an exploded State of the liquid crystal device, and
`FIG. 3 is a cross-sectional view of the liquid crystal device.
`The present invention is characterized in a mounting struc
`ture for a semiconductor device (IC) and a connecting
`structure for a flexible wiring board. Since the structure of
`a section for displaying images in the liquid crystal device
`is similar to that of a well-known type of liquid crystal
`device, electrode patterns formed on Substrates constituting
`the liquid crystal device, and the like are schematically
`shown in FIGS. 1 and 2, and a detailed description thereof
`is omitted.
`As shown in FIGS. 1, 2, and 3, in a passive matrix type
`liquid crystal device 1, a first transparent substrate 10 made
`of glass, quartz, plastic, or the like and a second transparent
`Substrate 20 similarly made of glass, quartz, plastic, or the
`like are fixedly bonded with a predetermined clearance
`therebetween so as to hold a sealing material 30 therebe
`tween. The sealing material 30 is provided with a break
`portion serving as a liquid crystal inlet 301 when injecting
`liquid crystal therethrough, and is sealed by a sealant 302
`made of an ultraviolet-curing resin. Liquid crystal 5 is sealed
`in a liquid crystal sealing region 300 enclosed by the sealing
`material 30 between the first transparent substrate 10 and the
`second transparent substrate 20. The first transparent sub
`strate 10 and the second transparent substrate 20 are pro
`vided, respectively, with electrode patterns 15 and 25 for
`driving which are made of transparent ITO (Indium Tin
`Oxide) films in Stripes so as to extend in orthogonal direc
`tions. Driving signals are applied to the electrode patterns so
`as to drive liquid crystal at pixels. In a case in which the
`liquid crystal device is of a reflective or transflective type,
`one of the electrode patterns may be made of a reflective
`metal film of aluminum or the like.
`Alignment layers 101 and 201 are formed, respectively,
`on the surfaces of the first transparent substrate 10 and the
`second transparent substrate 20. As the liquid crystal 5,
`various types of liquid crystals, such as STN (SuperTwisted
`Nematic) type, may be used.
`A pixel is formed by liquid crystal at the intersection of
`the two electrode patterns 15 and 25 to which voltage is 45
`applied from the electrode patterns. Since this embodiment
`adopts the passive matrix type liquid crystal device, one of
`the electrode patterns 15 and 25 functions as a scanning
`electrode to which a scanning signal is applied, and the other
`electrode pattern functions as a signal electrode to which 50
`on-voltage and off-voltage image signals are applied. Fur
`thermore, polarizers 19 and 29 are stuck on the outer
`surfaces of the first transparent substrate 10 and the second
`transparent substrate 20. Between the transparent substrates
`10 and 20 and the polarizers 19 and 29, a retardation film is 55
`interposed so as to cancel coloring caused in the liquid
`crystal layer, as necessary.
`In the liquid crystal device 1 of this embodiment, since the
`second transparent substrate 20 is larger than the first
`transparent substrate 10, a portion thereof protrudes from the 60
`edge of the first transparent substrate 10. In the protruding
`portion 200 of the second transparent substrate 20, a flexible
`wiring board connecting region 80 is formed along the edge
`of the second transparent Substrate 20, and an IC mounting
`region 70 is formed in parallel with and on the inner side of 65
`the flexible wiring board connecting region 80. The IC
`mounting region 70 is a region where a driving IC 7 for
`
`6
`outputting driving signals to the electrode patterns 15 and 25
`is mounted, and the flexible wiring board connecting region
`80 is a region where a flexible wiring board 8 for supplying
`various signals and power from the outside to the driving IC
`7 is connected to the second transparent substrate 20. The
`driving IC 7 serves to apply driving signals to the electrode
`patterns so as to drive pixels in the liquid crystal device, and
`is mounted in chip form on the transparent substrate by COG
`(Chip On Glass) method with its active surface opposing the
`substrate.
`When the first transparent substrate 10 and the second
`transparent substrate 20 are bonded by the sealing material
`30, the electrode patterns 15 formed on the first transparent
`substrate 10 are electrically connected to the ends of wiring
`patterns 94 extending from both ends of the IC mounting
`region 70 of the second transparent substrate 20 via an
`intersubstrate conducting material contained in the sealing
`material 30.
`In this embodiment, the IC mounting region 70 and the
`flexible wiring board connecting region 80 are generally
`structured, as shown in FIGS. 4 and 5 as partly enlarged
`views.
`FIG. 4 is a perspective view showing a state in which the
`driving IC 7 is mounted on the IC mounting region 70 of the
`liquid crystal device 1 according to the first embodiment of
`the present invention, and FIG. 5 is a perspective view
`showing a state in which the flexible wiring board 8 is
`connected to the flexible wiring board connecting region 80.
`In the IC mounting region 70, an electrical connection
`between the driving IC 7 and the wiring patterns 25 and an
`electrical connection between the driving IC 7 and the
`intersubstrate conducting wiring patterns 94 are made. Since
`the connections are basically the same in structure, FIGS. 4
`and 5 show only the electrical connection between the
`driving IC 7 and the wiring patterns 25. Illustration and
`description of the electrical connection between the driving
`IC 7 and the intersubstrate conducting wiring patterns 94 are
`omitted.
`Referring to FIG. 4, the IC mounting region 70 and the
`flexible wiring board connecting region 80 are connected by
`wiring patterns 9 formed of a conductive film, Such as an
`ITO film or an aluminum film, simultaneously with forma
`tion of the driving electrode patterns 25. The ends of the
`wiring patterns 9 placed inside the IC mounting region 70
`form multiple first terminals 91 (a first terminal group).
`Multiple first electrodes 71 (a first electrode group) formed
`on the active surface of the driving IC 7 are connected to the
`first terminals 91. The first electrodes 71 serve to input
`signals and voltages from the flexible wiring board 8. The
`first electrodes 71 are usually shaped like protuberances so
`as to serve as bump electrodes.
`In the second transparent substrate 20, the ends of the
`electrode patterns 25 placed inside the IC mounting region
`70 form multiple third terminals 93. Since the third terminals
`93 are formed in the same number and at the same pitch as
`those of third electrodes 73 formed on the active surface of
`the driving IC 7, the third electrodes 73 electrically contact
`the third terminals 93 in a one-to-one correspondence. The
`third electrodes 73 serve to output driving signals to the
`electrode patterns 25 so as to drive the liquid crystal. The
`third electrodes 73 are also usually shaped like protuber
`ances so as to serve as bump electrodes.
`As shown in FIG. 5, the ends of the wiring patterns 9
`placed in the flexible wiring board connecting region 80
`form multiple second terminals 92 (a second terminal
`group), and multiple second electrodes 82 (a second elec
`
`30
`
`35
`
`40
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`7
`trode group) formed on the flexible wiring board 8 are
`connected to the second terminals 92.
`Referring again to FIG. 4, wiring patterns 9A, 9B, 9C of
`the plural wiring patterns 9, which Supply Voltages. Such as
`a ground potential VSS and a high-voltage potential Vdd,
`from the flexible wiring board 8 to the driving IC 7, are
`formed so as to be wider than other wiring patterns 9 for
`transmitting signals, for example, a wiring pattern 9D, and
`are extended to the IC mounting region 70 and the flexible
`wiring board connecting region 80. Therefore, some of the
`first electrodes 71 of the driving IC 7 are collectively and
`electrically connected to each of the wiring patterns 9A, 9B,
`and 9C. Similarly, some of the second electrodes 82 of the
`flexible wiring board 8 are collectively and electrically
`connected to each of the wiring patterns 9A, 9B, and 9C.
`Terminals 91A, 91B, and 91C of the first terminals 91,
`which are connected to the wiring patterns 9A, 9B, and 9C,
`are not entirely provided with conductive films for forming
`the first terminals 91 and the wiring patterns 9, and the
`portions thereof having no conductive films form slits 96.
`For this reason, the terminal 91A is divided into four
`terminals (divided terminals) 911A, 912A,913A, and 914A
`in a comb-like form by slits 96, and the first electrodes 71
`of the driving IC 7 are placed on the four terminals 911A,
`912A,913A, and 914A in a one-to-one correspondence so as
`to be electrically connected thereto. Similarly, the first
`terminal 91B is divided into two terminals (divided termi
`nals) 911B and 912B in a comb-like form by a slit 96, and
`the first electrodes 71 of the driving IC 7 are placed on the
`two terminals 911B and 912B in a one-to-one correspon
`dence so as to be electrically connected thereto. The first
`terminal 91C is also divided into two terminals (divided
`terminals) 911C and 912C in a comb-like form by a slit 96,
`and the first electrodes 71 of the driving IC 7 are placed on
`the two terminals 911C and 912C in a one-to-one corre
`spondence so as to be electrically connected thereto.
`In contrast, in this embodiment, the ends of the wiring
`patterns 9A, 9B, and 9C on the side of the flexible wiring
`board connecting region 80 form second terminals 92A,
`92B, and 92O which are solid and even wider than a second
`terminal 92D formed at the end of the wiring pattern 9D, and
`some of the second electrodes 82 of the flexible wiring board
`80 are collectively and electrically connected to each of the
`terminals 92A, 92B, and 92C. The second terminal 92D of
`the wiring pattern 9D has a size corresponding to that of
`45
`each second electrode 82 of the flexible wiring board 80.
`FIGS. 6(A) to 6(C) are process sectional views schemati
`cally showing a state in which the driving IC is mounted on
`the IC mounting region of the second Substrate in the liquid
`crystal device according to the first embodiment of the
`50
`present invention. FIGS. 6(A) to 6(C) are sectional views of
`the IC mounting region, taken along line B-B' in FIG. 1.
`In the production procedure of the liquid crystal device 1
`of this embodiment, an anisotropic conductive film 6 is used
`to mount the driving IC 7 on the second transparent substrate
`20, as shown in FIG. 6(A). In this mounting method using
`the anisotropic conductive film 6, first, an anisotropic con
`ductive film 6 is applied on the IC mounting region 70, or
`a sheet-like anisotropic conductive film 6 is placed on the IC
`mounting region 70. Then, the first electrodes 71 of the
`driving IC 7 are respectively aligned with the first terminals
`91 formed on the second transparent substrate 20. In this
`state, as shown in FIG. 6(B), the driving IC 7 is heated and
`press-bonded to the second transparent substrate 20 by a
`head 60. As a result, as shown in FIG. 6(C), a resin
`component 61 contained in the anisotropic conductive film
`6 is melted, and conductive pa