SEL EXHIBIT NO. 2030
`
`INNOLUX CORP. v. PATENT OF SEMICONDUCTOR ENERGY
`LABORATORY CO., LTD.
`
`IPR2013-00028
`
`

`

`(12) United States Patent
`Tani
`
`I IIIII
`
`11111111 1111111111 IIIII IIIII IIIII IIIII 111111111111111 11111111
`US006392735Bl
`US 6,392, 735 Bl
`May 21,2002
`
`(10) Patent No.:
`(45) Date of Patent:
`
`(54) LIQUID CRYSTAL DISPLAY APPARATUS
`WlTH SEALING ELEMENT INCLUDING
`CONDUCTIVE SPACERS
`
`(75)
`
`Inventor: Masatoshi Tani, 1bkyo (JP)
`
`(73) Assignee: NEC Corporation, Tokyo (JP)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. No.: 09/671,160
`
`(22) Filed:
`
`Sep. 28, 2000
`
`(30)
`
`Foreign Application Priority Data
`
`Sep. 29, 1999
`(JP) ........................................... 11-276014
`Int. Cl.7 .............................................. G02F 1/1339
`(51)
`(52) U.S. Cl ..... ................... 349/156; 349/155; 349/157;
`349/153
`(58) Field of Search ................................. 349/155, 156,
`349/38, 39, 106, 149, 152, 153
`
`(56)
`
`References Cited
`
`U.S. PATENT OOCUMEN'J'S
`
`4,600,273 A • 7/1986 Obno ......... ................ 349/155
`5,748,266 A * 5/1998 Kodatc ........................ 349/39
`* 5/1998 Miyazaki et al. ........... 349/106
`5,757,451 A
`
`5,982,47! A • 11/!999 Hirakata el al ............. 349/155
`6,088,071 A • 7/2000 Yamamoto et al. ........... 349/38
`6,147,729 A * 11/2000 Kurauchi et aJ. ........... 349/106
`FOREIGN PATENT DOCUMENTS
`
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`
`2-220031
`4-153626
`4-350626
`8-262484
`9-152620
`10-68955
`11-183915
`ll-24892'1
`
`9/1990
`5/1992
`12/1992
`10/1996
`6/1997
`3/1998
`7/1999
`9/1999
`
`* cited by examiner
`
`Primary Examiner-Kenneth Parker
`Assistant Examiner-David Chung
`(74) Auomey, Agent, or Firm-McGinn & Gibb, PLLC
`
`(57)
`
`ABSTRACT
`
`In a liquid crystal display apparatus, a transfer electrode is
`formed on a first insulating substrate, and a columnar spacer
`and a counter electrode are formed on a second insulating
`substrate. A sealing element formed by seal material and
`conductive spacers adheres and seals the first and second
`insulating substrates, so that the counter electrode is in
`contact with the transfer electrode through the conductive
`spacers.
`
`20 Claims, 14 Drawing Sheets
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`US 6,392,735 Bl
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`2
`and remarkably decreasing the resistance between a counter
`electrode and a transfer electrode.
`According to the present invention, in an LCD appararus,
`a transfer electrode is formed on a first insulating substrate,
`5 and a columnar spacer and a counter insulating substrate,
`and a columnar spacer and a counter electrode are formed on
`a second insulating substrate. A sealing element formed by
`seal material and conductive spacers adheres and seals the
`first and second insulating substrates, so that the counter
`10 electrode is in contact with the transfer electrode through the
`conductive spacers.
`Also, in a method for manufacturing an LCD apparatus,
`a transfer electrode is formed on a first insulating substrate,
`a first columnar spacer and electrode a counter are formed on
`a second insulating substrate. lnen, seal material including
`conductive spacers is coated on a periphery of at least one
`of the first and second insulating substrates. Then, the first
`and second insulating substrates arc adhered, so that the
`counter electrode is in contact with the transfer electrode
`through the conductive spacers.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The present invention will be more clearly understood
`25 from the description set forth below, as compared with the
`prior art, with reference to the accompanying drawings,
`wherein:
`FIG. 1 is a plan view illustrating a first prior art LCD
`apparatus;
`FIG. 2 is a plan view illus trating the pixel portion of FIG.
`1;
`FIGS. 3 and 4 are cross-sectional views taken along with
`Ill and IV-IV, respectively, of FIG. 1;
`the lines Ill-
`FIG. 5 is a plan view illustrating a first prior art LCD
`apparatus;
`FIG. 6 is a plan view illustrating the pixel portion of FIG.
`5;
`Fl.G. 7 is a cross-sectional view taken along with the lines
`40 VTI-VII of FIG. 5;
`FIG. 8 is a plan view illustrating a first embodiment of the
`LCD apparat11s according to the present invention;
`FIG. 9 is a plan view illustrating the pixel portion of FIG.
`8;
`FIGS. 10 and 11 are cross-sectional views taken along the
`lines X-X and XI-XI, respectively, of FIG. 8;
`FIG. 12 is a plan view illustrating a pixel portion of a
`second embodiment of the LCD apparatus according to the
`present invention;
`FIG. l3 is a cross-sectional view of the apparatus of FIG.
`12; and
`FIG. 14 is a cross-sectional view illustrating a modiftca(cid:173)
`tion of FIG. 13.
`
`1
`LIQUID CRYSTAL DISPlAY APPARATUS
`WITH SEAUNG ELEMENT INCLUDING
`CONDUCTIVE SPACERS
`BACKGROUND OF THE INVENTION
`L Field of the Invention
`The present invention relates to a liquid crystal display
`(LCD) apparatus and its manufacturing method.
`2. Description of the Related Art
`Generally, an LCD apparatus is constructed by a trans(cid:173)
`parent insulating substrate on which: thin film transistors,
`pixel electrodes and the like are formed, and a counter
`transparent insulating substrate (counter substrate) on which
`a counter electrode is formed. In this case, the voltage at the
`counter electrode should be maintained at a predetermined 15
`value.
`In a first prior art LCD appararus (see JP-A-2-220031 &
`JP-A-4-153626), in order to apply a voltage to the counter
`electrode, transfer electrodes are provided on two or four
`edges of the transparent insulating substrate. The counter 20
`electrode is in contact with the transfer electrodes by paste
`including conductive spacers. This will be explained later in
`detail.
`In the above-described first prior art LCD apparatus,
`however, since the number of the transfer electrodes is
`limited, the resistance between the transfer electrodes and
`the counter electrode is so large that the voltage at the
`counter electrode cannot be maintained at a predetermined
`value. Also, since the diameter of sea ling peripheral spacers
`is about the same as that of the conductive spacers while the 30
`gap for the sealing peripheral spacers is difterent from the
`gap for the conductive spacers, stress may be generated so
`that irregular display occurs, thus degrad.ing the display
`quality. Further, since the seaHng peripheral spacers press
`data bus lines as well as scan bus lines, the data bus lines and 35
`the scan bus lines may be disconnected. Additionally, since
`a step for coating seal material is different from a step for
`coating the paste including conductive spacers, the manu(cid:173)
`facturing cost may be increased.
`In a second prior art LCD apparatus (se e JP-A-8 -
`262484), an auxiliary line also serves as means for applying
`a voltage to a counter electrode via a columnar spacer. That
`is, in order to electrically connect the auxiHary line to the
`counter electrode, the columnar spacer formed by color filter
`layers is provided at pixels. This also will be explained later 45
`in detail.
`In the above-described second prior art LCD apparatus,
`since a voltage is applied from a large number of location to
`the counter electrode, the resistance between the auxiliary
`line and the counter electrode is so small that the voltage at 50
`the counter electrode can be surely maintained at a prede(cid:173)
`termined value. Also, si nce no stress is generated, irregular
`display may not occur, thus improving the display quality.
`Further, the data bus Lines and the scan bus Lines may not be
`disconnected. Additionally, since a step for dispersing dis- 55
`play spacers is unnecessary, the manufacturing cost can be
`decreased.
`In the above-described second prior art LCD apparatus,
`however, if the counter electrode is a little oxidized or
`contaminated by insulating material, the counter electrode is
`no t always in contact with the auxiliary line, so that the
`electrical connection therebetween is unstable, particularly
`when vibration or impact is applied to the LCD apparatus.
`SUMMARY OF '11-IE INVENTION
`It is an object of the present invention to provide an LCD
`apparatus and its manufacturing method, capable of stably
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`Before the description of the preferred embodiments,
`60 prior art LCD apparatuses will be explained with reference
`to FIGS. 1, 2, 3, 4, 5, 6 and 7.
`In FIG. l , which illustrates a first prior art LCD apparatus
`(see JP-A-2-220031 & JP-A-4-153626), scan bus lines SL
`and data bus lines DL are provided on a transparent iosu-
`65 lating substrate 10, and pixels Pu formed by a TFT Q;i and
`a transparent pixel electrode E;i are provided at intersections
`between the scan bus lines SL and the data bus lines DL.
`
`

`

`US 6,392,735 Bl
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`Also, terminals 11 are provided on the transparent insulating
`substrate 10 and are connected to the scan bus lines SL and
`the data bus lines DL. Also, a sealing element 31 is provided
`on the periphery of the transparent insulating substrate 10,
`where a liquid crystal injecting opening IN is provided. s
`Further, a clogging element 32 is provided to clog liquid
`crystal within the sealing element 31.
`lo FIG. 1, a counter transparent insulating substrate
`(hereinafter, simply referred to as a counter substrate) 20 and
`a counter electrode 23, which are not shown in FIG. 1, but
`are shown in FIGS. 3 and 4, are provided.
`In order to apply a definite voltage to the counter electrode
`23, four transfer electrodes U are provided on the four edges
`of the transparent insulating substrate 10 within the sealing
`element 31.
`In FIG. 2, which illustrates the pixel !\ of FIG.1, the TFT
`Q1i is formed by a gate electrode G shunted f1om the scan
`bus lined SL1, a semiconductor active layer A made of
`amorphous silicon opposing the gate electrode G, a drain
`electrode D shunted from the data bus line DLi and a source
`electrodeS connected to the transparent pixel electrode E1r
`One end of the semiconductor active layer A is connected to
`the source electrodeS, while the other end of the semicon(cid:173)
`ductor active layer A is connected to the drain electrode D. 25
`In FIG. 2, note that OP designates an opening of an optical
`shield block matrix layer 21 (see FIGS. 3 and 4).
`Also, in FIG. 2, the adjacent scan bus Jjoe SLi+l is partly
`superposed onto the transparent pixel electrode E,i, to
`increase the capacitance thereof. This is called a gate storage
`type.
`lo FIGS. 3 and 4, which are cross-sectional views taken
`along the lines III-III and IV-IV, respectively, of FIG. 1,
`a conductive layer 121 and an insulating layer 13 are formed
`on the transparent insulating substrate 10. Note that the
`conductive layer U1 is also used for the scan bus lines SL1 ,
`SL1_J> ••• of FIG. 2. Also, a conductive layer U2 is formed
`on the conductive layer 122 (DL) serves as the data bus line
`DLi, Dlj+l• ... of FIG. 2. Further, a conductive layer 123
`is formed on the conductive layer 122 and the insulating
`layer 13. Note that the conductive layer U3 (E) serves as
`transparent pixel element Eu of FIG. 2. Additionally, an
`insulating layer 14 is formed on the entire surface except for
`the conductive layer 123. Also, an orientation layer 15 is
`formed on the conductive layer U3 (E).
`The conductive layers 121, 122 and123 form the transfer
`electrode U.
`On the other band, an optical shield black matrix layer 21
`and a red color filter layer 22 are formed on the counter
`substrate 20. Also, a counter electrode 23 is formed on the
`optical shield black matrix layer 21 and the red color filter
`layer 22. Further, an orientation layer 24 is formed on the red
`color filter 22.
`The transparent insulating substrate 10 and the counter
`substrate 20 are adhered by the sealing element 31 formed
`by peripheral spacers 3la enclosed by seal material 31b. Jn
`this case, conductive spacers 34a enclosed by paste 34b are
`provided in order to electrically connect the transfer elec(cid:173)
`trode 12 to the counter electrode 23. Simultaneously, display 60
`spacers 35 are dispersed into a cell gap CG between the
`transparent insulating substrate 10 and the counter substrate
`20 surrounded by the sealing element 31, thus maintaining
`the cell gap CG.
`Additionally, polarization plates 41 and 42 are adhered to 65
`the transparent insulating substrate 10 and the counter
`substrate 20, respectively.
`
`4
`In the LCD apparatus of FIGS. 1, 2 and 3, since the
`diameter of the peripheral spacers 31a is about the same as
`that of the conductive spacers 34a and the paste 34b bas the
`same material as the seal material 31b, the contact charac(cid:173)
`teristics and thermal expansion coefficient of the paste 34b
`are about the same as those of the sealing element 31, so that
`the cell gap CG between the transparent insulating substrate
`10 and the counter substrate 20 can be uniform. Also, since
`the ratio of the conductive spacers 34a to the paste 34b is
`10 small, i.e., about 0.5 wt %, the conductive spacers 34a are
`hardly in contact with liqujd crystal filled in the cell gap CG
`between the transparent insulating substrate 10 and the
`counter substrate 20, which increases the lifetime of the
`liquid crystal and improves the display quality.
`In the LCD apparatus of FIGS. 1, 2 and 3, however, since
`the number of the transfer electrodes 12 is limited, the
`resistance between the transfer electrodes 12 a.nd the counter
`electrode 2..l
`is so large that the vol tage at the counter
`electrode 23 cannot be maintained at a predetermined value.
`Also, since the diameter of the peripheral spacers 31a is
`about the same as that of the conductive spacers 34a while
`the gap for the peripheral spacers 31a is different from the
`gap for the conductive spacers 34a, stress may be generated
`so that irregular display occurs, thus degrading the display
`quality. Further, as illustrated in FIG. 4, since the peripheral
`spacers 31a press the data bus Jines DL as well as the scan
`bus lines SL, the data bus lines DL and the scan bus lines SL
`may be ilisconnected. Additionally, since a step for coating
`the seal material3lb is different [1om a step for coating the
`30 paste 34b, the manufacturing cost may be increased.
`In FIG. 5, which illustrates a second prior art LCD
`apparatus (see JP-A-8-262484), an auxiliary line AL1 is
`partly superposed onto the transparent pixel electrode P1i as
`illustrated in FIG. 6, to substantially increase the capacitance
`35 thereof. In this case, the auxiliary line AL1 also serves as
`means for applying a voltage to the counter electrode 23 via
`a columnar spacer CS.
`In FIG. 7, which is a cross-sectional view taken along the
`line VII-VII of FIG. 5, in order to electrically connect the
`auxiliary lineAL, to the counter electrode 23, the columnar
`spacer CS [ormed by a green color filter layer 22' and a blue
`color filter layer 22" is provided.
`to FIG. 7, note that N+designates an N-type impurity
`45 region and 16 designates an insulating layer.
`ln the LCD apparatus of FIGS. 5, 6 and 7, since a voltage
`is applied from a large number of locations, i.e., the loca(cid:173)
`tions of the pixels P1i
`to the counter electrode 23, the
`resistance between the auxiliary line AL1 and the counter
`50 electrode 23 is so small that the voltage at the counter
`electrode 23 can be surely maintained at a predetermined
`value. Also, since no stress is generated, irregular display
`may not occur, thus improving the display quality. Further,
`since the peripheral spacers 31a of FIG. 4 are unnecessary,
`55 the data bus lines DL and the scan bus lines SL may not be
`disconnected. Additionally, since a step for coating the paste
`34b of FIG. 3 and a step for dispersing the display spacers
`35 of FIG. 3 are unnecessary, the manufacturing cost can be
`decreased.
`In the LCD apparatus of FIGS. 5, 6 and 7, however, if the
`counter electrode 23 is a little oxidized or contaminated by
`insulating materi.al, the counter electrode 23 is not always in
`contact with the auxiliary line AL,, so that the electrical
`connection therebetween is unstable, particularly when
`vibration or impact is applied to the LCD apparatus.
`FIG. 8 is a plan view illustrating a first embodiment of the
`LCD apparatus according to the present invention, FIG. 9 is
`
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`a plan view of the pixel portion of FIG. 8, and FIGS. 10 and
`11 are cross-sectional views taken along the lines X-X and
`XI-XI, respectively, of FIG. 8. Note that FIG. 9 is the same
`as FIG. 2.
`In FIGS. 8, 10 and 11, the sealing element 31 formed by s
`the peripheral spacers 31a enclosed by the seal material 31b
`and the conductive spacers 34a enclosed by the paste 34b of
`the LCD apparatus of FIGS. 1, 3 and 4 are replaced by a
`sealing element 36 fom1ed by conductive peripheral spacers
`36a enclosed by seal materia136b. Also, a transfer electrode 10
`12' is provided at the periphery of the transparent insulating
`substrate LO corresponding to the sealing element 36.
`As illustrated in FIGS. 10 and 11, a columnar spacer CS'
`formed by the red color filter layer 22, the green color filter
`layer 22' and the blue color filter layer 22" is provided to
`correspond to the transfer electrode 12'.
`Thus, since the transfer electrode 12' is widely provided
`at the periphery of the transparent insulating substrate 10,
`the resistance between the transfer electrode 12' and the
`counter electrode 23 is decreased so that the voltage at the
`counter electrode 23 can be surely maintained at a prede-
`termined value. Also, since the gap between the transfer
`electrode .12' and the counter electrode 23 is adjusted by the
`columnar spacer CS', stress may not be generated so that
`irregular display may not occur, thus improving the display
`quality. Further, as illustrated in FIG. 11, the conductive 25
`peripheral spacers 36a do not press the data bus lines DL as
`well as the scan bus lines SL, the data bus lines DL and the
`scan bus lines SL may not be disconnected. Additionally,
`since a step for coating the paste 34b of the LCD apparatus
`of FIG. 3 is unnecessary, the manufacturing cost can be
`decreased. Further, since the counter electrode 23 is com(cid:173)
`pletely in contact with the transfer electrode 12' by the
`conductive peripheral spacer 36b, the electrical connection
`between the counter electrode 23 and the transfer electrode
`12' is stable even if vibrat-ion or impact is applied to the LCD
`apparatus.
`The method for manufacturing the LCD apparatus of
`FIGS. 8, 9, 10 and It will be explained below.
`First an about 0.5 to 1.5 mm thick transparent insulating 40
`substrate 10 made of inorganic glass such as silica glass,
`boric silicic acid galss, alumina silicic acid glas.s or soda
`lime glass, or organic plastic is prepared. The transparent
`insulating substrate 10 is cleaned and rinsed by cleaning
`liquid and pure water to remove contamination and particles 45
`o n the surface thereof.
`Next, an about 100 to 300 om thick conductive layer 121
`made of Cr, AI, Ta or Mo is deposited on the transparent
`insulating layer 10 by a vacuum sputtering process. Then,
`the conductive layer 121 is patterned to form the terminals 50
`11, the scan bus lines SL (the gate electrode G) and the
`conductive layer 121 of the transfer electrode 12'.
`Next, an about 200 to 300 om thick insulat"ing layer 13
`made of silicon oxide or silicon nitride, an about 50 to 300
`om thick non-doped amorphous silicon layer (not shown) 55
`and an about 30 to 100 om thick doped amorphous silicon
`layer (not shown) are sequentially deposited on the entire
`surface. Then, the insulating layer 13, the non-doped amor(cid:173)
`phous silicon layer and the doped amorphous silicon layer
`are patterned. In this case, the patterned insulating layer 13 60
`also serves as a gate insulating layer (not shown) of the TFT
`0;;, the patterned non-doped amorphous silicon layer (not
`shown) serves as a channel layer of the TFT O;p and the
`patterned doped amorphous silicon layer (not shown) serves
`as contact regions of the TFT 0;;-
`Next, an about 100 to 300 nm thick conductive layer 122
`made of Cr, Al, Ta or Mo is deposited on the entire surface
`
`6
`by a vacuum s puttering process. Then, the conductive layer
`122 is patterned to form the terminals 11, the data bus lines
`DL;, the drain electrode D, and the conductive layer 122 of
`the transfer electrode 12'.
`Next, an about 30 to 100 om thick conductive layer 123
`made of indium tin oxide (ITO) is deposited on the entire
`surface by a sputtering process. Then, the conductive layer
`123 is patterned to form the terminals 11, the pixel electrode
`E;; and the conductive layer 123 of the transfer electrode 12'.
`In this case, the pixel electrode E;; is connected to the source
`electrode S.
`Next, a part of the doped amorphous silicon layer (not
`shown) on tbe channel layer (not shown) is removed so that
`the source electrode S is electrically disconnected from the
`drain electrode D.
`Next, an insulating layer 14 made of silicon nitride is
`deposited on the entire surface by a chemical vapor depo(cid:173)
`sition (CVD) process, aod is patterned.
`Next, an about 50 to 100 om thick orientation layer 15
`made of polyimide is coated on the conductive layer 123
`except for the transfer electrode 12'. Then, the orientation
`layer 15 is baked at a temperatllfe of about 200° C. for about
`30 to 60 minutes. Then, a rubbing operation is performed
`upon the orientation layer 15 so that the molecules thereof
`are oriented at a predetermined angle.
`On the other band, another about 0.5 to 1.5 om thick
`transparent insulating substrate (counter substrate) 20 made
`of inorganic glass such as silica glass, boric silicic acid glass,
`alumina silicic acid glass or organic plastic is prepared. The
`counter substrate 20 is also cleaned and rinsed by cleaning
`liquid and pure water to remove contamination and particles
`on the surface thereof.
`Next, an about 100 to 200 om thick optical shield black
`matrix layer 21 made of Cr or CeO is deposited by a
`sputtering process. Then, the optical shield black matric
`layer 21 is patterned to form an opening OP of FIG. 9. Note
`that the optical shield black matric layer 21 can be made of
`a mixture of carbon black, titanium oxide powder, iron oxide
`powder or metal sulfide power with epoxy resin, acrylic
`resin, urethane resin, polyester resin, polyimide resin, poly-
`olefin resin or gelatin.
`Next, an about 0,5 to 2 ,urn thick red color filter layer
`22(R) made of a colorant such as an organic pigment, an
`inorganic pigment or a dye mixed with epoxy resin, acrylic
`resin, urethan resin, polyester resin, polyamide resin, poly-
`olefin resin or gelatin is coated and is patterned. In this case,
`the pallerned red color filter layer 22(R) remains at prede(cid:173)
`termined openings of the optical shield black matrix layer 21
`and also serves as a part of the columnar spacer CS'.
`Next, an about 0,5 to 2 ,urn thick red color filter layer
`22(R) made of a colorant such as an organic pigment, an
`inorganic pigment or a dye mixed with epoxy resin, acrylic
`resin, urethan resin, polyester resin, polyimide resin, poly(cid:173)
`olefin resin or gelatin is coated and is patterned. In this case,
`the patterned red color filler layer 22(R) remains at prede-
`termined openings of the optical shield black matrix layer 21
`and also serves as a part of the columnar spacer CS'.
`Next, an about 0.5 to 2 pm thick blue color filter layer
`22(B) is coated and is patterned. In tbis case, the patterned
`blue color filter layer 22(B) remains at predetermined open(cid:173)
`ings of the optical sbield black matrix layer 21 and also
`serves as a part of the columnar spacer CS'.
`Next, an about 50 to 100 om thick conductive layer made
`65 of ITO is deposited on the entire surface by a sputtering
`process. Then, the conductive layer 23 is patterned to form
`a counter electrode 23.
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`Next, an about 50 to 100 om thick orientation layer 24
`made of polyimide is coated on the conductive layer 23
`except for the columnar spacer CS'. Then, the orientation
`layer 24 is baked at an temperature of about 200° C. for
`about 30 to 60 minutes. Then, a rubbing operation is s
`performed upon the orientation layer 24 so that the mol(cid:173)
`ecules thereof are oriented at a predetermined angle.
`The coupling of the above-described transparent insulat(cid:173)
`ing substrate 10 and the counter electrode 20 is explained as
`follows.
`First, a seal materia.! 36a including conductive peripheral
`spacers 36b is coated at an about 0.1 to 0.5 wide periphery
`of the transparent insulating substrate 10 except for the
`liquid crysta.l injecting opening IN using a screen printing
`process or a dispenser. ln this case, the ratio of the conduc- 15
`live peripheral spacers 36b to the seal material 36a is about
`0.1 to 5 wt %. On the other hand, about 70 display spacers
`35 per mm2 having a diameter of about 4 to 6 pen arc
`dispersed onto a display area of the counter substrate 20 by
`using a wet-type or dry-type spacer dispersing apparatus. In 20
`this case, an area of the counter s ubstrate 20 except for the
`display area is masked.
`Next, the transparent insulating substrate 10 is aligned
`with the counter substrate 20, so that the transfer electrode
`U ' corresponds to the columnar spacer CS'.
`Next, the seal material 36a is hardened by applying beat
`or ultraviolet irradiation thereto. As a result, the transfer
`electrode 12' is electrically connected to the counter elec(cid:173)
`trode 23. In tbis case, since the diameter of the conductive 30
`periphera.l spacers 36b is smaller than the gap where the data
`bus lines DL as well as the scan bus lines SL are formed, no
`stress is applied thereto.
`Next, liquid crystal is injected by a vacuum process from
`the liq11id crystal injecting opening IN into the gap between
`the tra.nsparent insulating substrate 10 and the counter
`substrate 20 within the sealing element 36.
`Next, the liquid crystal injecting opening IN is sealed by
`clogging element 32 made of silicone resin, ultraviolet cured
`resin, epoxy resin or acrylic resin.
`Finally, the outer surfaces of the transparent insulating
`substrate 10 and the counter substrate 20 are rinsed, and
`then, polarization plates 41 and 42 are adhered thereto.
`Thus, the LCD apparatus is completed.
`In the above-described fi rst embodiment, although the
`seal material 36a is coated on the transparent insulating
`substrate 10, the seal material 36a can be coated on the
`counter substrate 20 or on both of the substrates 10 and 20.
`Also, although the display spacers 35 is dispersed onto the 50
`counter substrate 20, the display spacers 35 can be dispersed
`onto the transparent insulating substrate 10 or on both of the
`substrates 10 aod 20.
`According to the inventer's experiment, in a 10.2 em (0.4
`inches) LCD apparatus, when the conductive peripheral
`spacers 36b had a diameter of 3 ,um and the density of the
`conductive peripheral spacers 36b was more than 200/ mm2
`(0.1 wt % ),the resistance between the counter electrode 23
`and the transfer electrode U ' was less than 5 Q. Also, if the
`density of the conductive peripheral spacers 36b was 100/
`mm2 (0.05 wt % ), the increase of the above-mentioned
`resistance was not observed under a pressure-quicker test
`where the temperature w