( 19) Japan Patent Office (JP)
`
`(II) Japanese Unexamined Patent
`
`(12) Japanese Unexamined Patent
`
`Application Publication (A)
`
`H2-.!HI25
`
`(51) In1. C1.s
`
`GOZ F
`
`1/136
`HOI L 29/784
`
`Identificatio
`
`JPO file
`
`(43) Publication date: September 17.
`
`n symbols
`
`500
`
`number
`7370-:!H
`
`8624-5F
`
`1990
`
`H 01
`
`L
`
`29/78
`
`311 A
`
`Request for examination: Not yet requested No of claims: 2 (Total of 25 pages)
`
`(54) Title of the Invention
`Liquid crystal display device
`(:!1) Application number
`(22) Date of application
`(n) Inventor
`Hideaki Taniguchi
`
`HI-53819
`March 8. 1989
`clo Mobara Factory of Hitachi, Ltd.
`
`3300 Hayano, Mobara-shi, Chiba
`
`(72) Inventor
`
`RyoJi Oritsuki
`
`c/o Mobara Factory of Hitachi. Ltd.
`
`(n) [nventor
`
`Akira Sasano
`
`3300 Hayano, Mobara-shi. Chiba
`
`cia Mobara Factory of Hitachi, Ltd.
`3300 Hayano. Mobara-shi, Chiba
`
`(71) Applicant
`
`Hitachi, Ltd.
`
`4-6 Kandasurugadai. Chlyoda-ku, Tokyo
`
`(74) Representative
`
`[Patent Attorney]
`
`and one other
`
`Katsuo Ogawa
`
`CMO 0183104
`
`Exhibit 1006, page 1
`
`

`

`Specifications
`I. Title of the Invention
`LIquid crystal display device
`
`2. Claims
`(I). An active matrix liquid crystal display
`device comprising thin-film transistors and
`picture element electrodes as a component
`for a picture element, with II picture signal
`wire being placed on om: uf the transparent
`substrates. and a drain electrode of said
`thin-film transistor being plilced on the area
`corresponding to said signal wire on the
`other
`transparent
`substrate,
`wherein
`electrodes constituting the voltage retention
`elements along with said picture elements
`are provided.
`
`l~). An active matm. liquid crystal display
`device comprising thin-film transistors and
`picture element electrodes as II component
`for a picture element, with a pictUre signal
`wire bemg placed on one of the transparent
`substrates, and a drain electrode of said
`thm-fiIm transistors being placed on the
`area corresponding to said signal wire on
`the other transparent substrate. wherein at
`least either of a scanning signal wire or said
`picture signal wIre cOQSists of a plurality of
`conductive layers
`
`3. Detailed Descnption on the InventlOn
`[lndustnal Field of the Invention]
`Thc invention relates to a liqUid crystal
`display device such as active matrix color
`liqUid display devices
`comprising,
`for
`
`thin-film transistors and picture
`example,
`element electrodes
`(Prior Art]
`The existing active mJtrix liquid crystal
`display devices, as shown in Japan Display
`'86), page 8...
`- 87,
`include thin-film
`transistors, Picture element electrodes, and
`II scanning signal wire placed on II lower
`transparent substrate. picture signal wire
`placed on an upper transparent substrate,
`the
`thin-film
`\vith drain electrodes of
`tranSIStOrs placed on the area corresponding
`to the picture signal wire on the lower
`transparent substrate.
`the
`In a liquid crystal display deVice.
`scanning Signal wire is placed on the lower
`transparent substrate and the picture signal
`wire is placed on the upper transparent·
`substrate, preventmg short-out between the
`scanning signal wire and picture signal wire
`circuits, providmg a good yield.
`[Problem to be Solved by the Invention]
`In such liquid crystal displays. however. a
`superposition
`capacitance
`is
`formed
`between a gate electrode and a source
`electrode. which imposes direct current
`components sometimes causing black stains
`and black surface defect. Furthermore, the
`scanning signal WIre and picture signal wire
`being formed on the single conductive layer
`m the display increase the resistance of the
`scanning signal wire and picture signal wire.
`which sometimes' causes a writmg error in
`the picture element electrode. A possible
`solution tOr this problem IS to mcrease the
`width of the scanning signal win: and
`
`CMO 0183105
`
`Exhibit 1006, page 2
`
`

`

`this lowers the
`
`picture signal wire. but
`aperture ratio
`This JDvention is intended to solve said
`problem. and the purpose is to provide a
`liquid crystal display deY1ce having II good
`yield \vithout incurring black stains or black
`surface defects, and a liquid crystal display
`deVice having a good yicld. no writing
`failure incurred by the picture element
`electrode, and a high aperture ratio.
`[Means for Solving the Problem]
`To achieve said purpose, in the invention,
`the thin-film tmnsistors and picture element
`electrodes are used as components of the
`picture element, with the picture signal wire
`being placed on one of the transparent
`substrates, and the drain electrode of said
`thin·film being
`placed
`in
`the
`area
`corresponding to said signal wire on the
`other
`transparent substrate. wherein the
`electrodes constituting the voltage retention
`elements are provided in the active-matrix
`liqUid crystal display.
`in order to achieve said
`Furthermore.
`in the invention.
`the tIun·fi 1m
`purpose.
`transistors and picture element electrodes
`are used as a compunent for the picture
`element, with the picture Signal wire being
`placed on one of the transparent substrates.
`and the drain ekctrode of said tIun-film
`belOg
`placed
`in
`the
`area
`transistors
`corresponding to said signal wire on the
`other transparent substrate, wherein at least
`either a scanning signal wIre or said picture
`signal wire consists of a plurahty of
`conducti\'e layers in the active-matri.,,< liquid
`
`crystal display.
`[Operation of the Invention1
`Because said liquid crystal display device
`electrodes
`constitute
`the
`retention
`has
`elements along with the picturc element
`electrodes. no direct current components
`are imposed on the liquid crystals even if
`superposition
`capacitance
`is
`fonnt:d
`between the gate electrode and the source
`electrode.
`Furthermore, because said liquid crystal
`display device has at least either a scanning
`signal wire or said picture signal wire
`consisting of a plurality of conductive
`resistance of the scanning signal
`layers.
`wire and picturc Signal wire are lowered
`even if the width ofsaid wires IS reduced.
`[Embodiments]
`FIG 2 {plain view of the main part) shows a
`picture element of the active-matrix color
`liquid crystal display device. to which the
`mvention is applied. and FIG 3 shows a
`cross-sectional view based on the II-II
`section lim:. Furthermore. FrG 4 (plain
`view of the main part) shows the main part
`of the liquid crystal display where there IS a
`plurality of picture elements shown in FIG.
`2.
`
`As shown in FIG 2 to FIG 4. the liqUid
`crystal display device has
`a thin-film
`transistor TFT and picture elements that
`a
`transpllrent
`pIcture
`element
`hllve
`ekctrode ITO on the inner surface of-the
`upper
`transparent glass substrate SVB I.
`The lower transparent glass substrate SUB I.
`for example.
`is approximately II mm
`
`CM00183106
`
`Exhibit 1006, page 3
`
`

`

`1"".
`
`thick.
`Each picture element IS placed within an
`area where two neighboring scannmg signal
`wires (gate signal wires or horizontal signal
`wires) GL and two neighboring PiCture
`signal wires (drain signal wires or vertical
`signal wires) DL cross (an area surrounded
`by the four signal wires). A plurality of
`scanning Signal wires GL, lIS shown In FIG.
`2 and FIG 4, extends honzontally. A
`plurality of PiCture signal wires DL ex.tends
`vertically and is arranged horizontally.
`The thm-film transistor TFf in each picture
`diVided
`into
`three
`element
`is
`(plumlityrTFTI.
`TFT.:!,
`and
`TFT3-within the picture element. All of
`the thin-film transistors TFTI to TFT3 have
`s~bstantially the same size (same channel
`length and width). The dh'ided thin-film
`transistors TFTI
`to TFT3 are mainly
`constituted of a gate electrode GT. an
`insulating film GI, an. i-type semiconductor
`layer AS comprising i-type (intrinsic, not
`doped with conductive type determinant
`impurity) silicon (Si I, and a pair of a source
`electrode SDI and a drain electrode SD:! It
`should be understood that the source and
`drain electrodes
`change
`their position
`during operation, as they are principally
`determined by a bias electrode m between
`and are re\'ersed during operation in the
`CirCUit of the liquid crystal display device.
`For
`convenience,
`the
`electrodes
`are,
`however, referred to as the source electrode
`in the
`following
`and drain electrode
`description.
`
`Said gate electrode GT, as shown in FIG
`5 (a plain view of the malO part
`in the
`IS placed
`speCific manufacturing process),
`vertically (downward 10 FIG 2 and FIG 51
`protruding from the scanning signal wue
`GL to form a T-shape (branched into
`T-shape). That is, the gate electrode GT is
`placed so as to extend substantively parallc1
`to the picture signal wIre DL. The gate
`electrode GT is placed so as to reach the
`thin-film transistors TFf I to TFf3 in the
`respective
`formation
`areas. The
`thin
`transistors TFTI
`to TIT3 share one gate
`electrode GT (as a common electrode).
`which is formed to connect with the same
`scanning signal \vire GL. The gate electrode
`GT is constituted of a smgle 1st conductive
`to minimize disalignment
`in the
`film gl
`formation area of the thm-fiIm trallsistor
`TFT. The 1st conductive film gl is formed
`with a thickness of approxImately 1100 A
`using a chromium (erl film formed by
`sputtering, for example.
`The gate electrode GT is--as shown In
`FIG 2, FIG 3, and FIG 6-formed slightly
`larger than the i-type semiconductor layer
`AS (as Viewed from below) to cover the
`entire layer Thus, when a backhght such as
`a fluorescent lamp is placed under the lower
`transparent glass substrate SUB I, the gate
`electrode GT constltuted of nontransp.u-ent
`chrome blocks light protcctmg thc i-type
`semiconductor layer AS from the backlight.
`which reduces the conductive phenomenon.
`which IS deterioration of off characteristics
`of the thin-film transistor TFf caused by
`
`CMO 0183107
`
`Exhibit 1006, page 4
`
`

`

`said lightmg. The minimum size of the gate
`electrode OT that has a sufficient width to
`cover the source and drain electrodes SDI
`and SD::! (including extra space to adjust the
`gate electrode and the source and drain
`in principle. and the
`electrode positions).
`depth detenmning the channel width W is
`determined in
`comparison with space
`between the source and drain electrodes
`(channel length) L, which is a factor WfL
`determining the interactive conductance
`gm.
`The size of the gate electrode in the
`liquid crystal display device, of course,
`should be larger than the aforementioned
`minimum size.
`the
`and
`gate
`the
`When
`only
`light-blocking feature of the gate electrode
`OT are considered, the gate electrode OT
`and its wiring OL may be Integrated into a
`slOgle layer, and in such a case,
`the
`nontransparent conductive material can be
`selected from aluminum (Al) containing
`slhcon,
`pure
`aluminum,
`aluminum
`containing
`palladium (Pd),
`aluminum
`
`titanium (Til,
`and
`silicon
`containing
`aluminum contaimng silicon and copper
`(CuI for examples.
`sl~al wire OL is
`Said
`scanning
`compounded
`film
`a
`constituted
`of
`comprising the 1st conductive layer gl and
`the 2nd conductive layer g:! placed on the
`gl The 1st conductive layer gl is formed in
`the same procedure as the Ist conductive
`In said gate electrode OT and has
`layer gl
`the same structure. The 2nd conductive
`
`layer g1 forms a thickness of approximately
`900 to 4,000 Athick using an alummum
`ftlm formed by sputtering, for example. The
`2nd conducth'e layer g2 is designed to
`lower the resistance value of the scanning
`signal wue OL and to enhance the signaling
`speed Iinformation write characteristic of
`the picture element).
`Furthermore, in the scanning signal wire
`OL, the 2nd conductive layer g:! is smaller
`than the 1st conductive layer g1. That IS,
`the scanning signal wire GL can reduce step
`levels on the sidewall, which smoothes the
`surface of the insulating film GI in the
`upper layer.
`The insulating film GI is used as the gate
`insulating film in thin-film transistors TIT 1
`to TFf3 The insulating film GI is formed
`in the upper layer of the gate electrode OT
`and
`scanning
`signal wIre OL. The
`insulating film GI
`forms a thickness of
`approximately 3500 Ausing a slhcon nitride
`tilm formed by a plasma CVD, for example.
`As mentioned above.
`the surface of the
`insulating film OJ
`is smoothed in the
`
`thin-film transistors
`formation areas of
`TFf[ to TFf3 and in the formation area of
`the scanning SIgnal wire OL.
`The i-type semIconductor layer AS IS-as
`shown in detail tn fIG 6 (a plain view of
`the main part in the speCIfic manufacturing
`process)-usN as the respective channel
`formation
`areas
`for dl\'ided
`thin-film
`transistors TFflto TFT3. Divided thin-film
`transistors TFTI to TFf3 share one i-type
`semiconductor layer AS within the picture
`
`CMO 0183108
`
`Exhibit 1006, page 5
`
`

`

`r
`
`'1
`
`thin·film
`diVIded
`is,
`That
`element.
`transistors TITI to TIT3 are fonned on
`one (common) i-type semiconductor layer
`AS island area The i-lype semIconductor
`layer AS is constituted of an amorphous
`silicon layer or a multi-crystal silicon layer
`2,ooo.A
`and
`foons
`an
`approximate
`thickness.
`
`The. i-type semiconductor layer AS is
`fonned,
`following the fonnation of the
`insulating film GI compnsing Si l N4• with
`the supply gas constituents changed and by
`the same plasma CDV deVice Without being
`exposed to the outside of the deVIce.
`Afterwards.
`the N+-type semiconductor
`layer dO doped with P for olunic contact
`(FIG 3) is fonned to have a thickness of
`approximately 300 Aby following the same
`process. After tIlls.
`the lower transparent
`glass substrate SUBI is removed from the
`deVIce,
`and
`the
`N+-type
`CVD
`semiconductor
`layer dO and the i-type
`semiconductor layer AS are patterned into
`an isolated island shape as shown in FIG 2.
`FIG 3, and FIG 6 usmg a photo processmg
`technique.
`Thus, one i-type semiconductor layer AS
`fonned
`for
`all
`diVIded
`thin-film
`is
`transistors TITI
`to TIT3 in the picture
`element, meaning
`a
`common
`dram
`by
`electrode
`SOl
`shared
`thin-film
`trnnslstors TITI to TIT 3 crosses only one
`i-type semiconductor layer AS from the
`drain electrode SO Side to the I-type
`semiconductor layer AS side. TIlls reduces
`possible
`discoWlectlons 10, the
`drain
`
`electrode S02 while reducing possible dot
`defects. That
`IS, the liquid crystal device
`reduces the dot defects to one-third, which
`is caused by the drain electrode S02 when
`i-type
`crossmg
`the
`steps
`in
`the
`semiconductor layer AS.
`Furthermore. unlike the layout of the
`liquid crystal display deyIce, when the
`picture signal wire DL directly crosses over
`the i-type senuconductor layer AS and the
`picture signal constitutes the drain electrode
`SOl where it crosses the layer, possible line
`to
`the
`defects, which
`are
`attributed
`disconnection caused by the picture signal
`wire DL (drain electrode SD.:!) crossing
`over the i-type semicon~uctor layer AS, are
`reduced That
`is, by sharing one i-type
`semiconductor layer AS, divided thm-film
`to TIT3 in the picture
`transistors TIT I
`elements keep the picture signal wire DL
`(drain electrode SD:!) from crossing over
`i-type semiconductor layer AS more than
`once (It actually crosses over twice at the
`beginnmg and the end of the crossover).
`Said i-type semiconductor layer AS is, as
`in FIG :! and FIG 6.
`shown 10 detail
`extended to the space between the scanning
`signal wire GL and the picture signal wire
`DL where the wires cross each other (01
`crossover
`part). The
`extended
`i-type
`layer AS is designed to
`semiconductor
`reduce short109 belwet:n the scarming signal
`wire GL and the pIcture signal wire DL
`to
`Divided thm-film transistors TITI
`TIT3 in the picture elements, and the
`respectl\'e source electrode SD I and train
`
`CMO 0183109
`
`Exhibit 1006, page 6
`
`

`

`electrode S02 are--as shown in detail in
`FIG 2, FIG 3 and FIG 4 (a plato view of
`the main part in the specific manufacturing
`process)---placed separately on said i-type
`st:miconductor
`layer AS
`The
`source
`electrode SOl and drain electrode SO are
`designed to switch between each other
`operationally as the circuit bias polarity
`changes. Tbat
`the thin-film' transistor
`is.
`TFT is bidirectional as is FET.
`
`and drain'
`The source electrode SOl
`electrode SO:! are constituted of a 1st
`conductive layer dl, a 2nd conductive layer
`d2, and a 3rd conductive layer d3 being
`lay~d in order beginning with the lower
`layer contacting the N+-type semiconductor
`layer dO. The 1st conductive layer dl, 2nd
`conductive layer dl. and 3rd conductive
`layer d3 on the source electrode SDI are
`fonned
`by
`following
`the
`same
`manufacturing process as those on the drain
`electrode S02.
`
`fonns ,a
`The 1st conductIVe layer dl
`tluckness of approximately 500 to 1,000 A
`(approx 600 A thick in the hquid crystal
`display device) using a chrome film fonned
`by sputtenng. The tilm should be fonned
`than 2,000 A. because the
`no thicker
`chrome film increases stress as it becomes
`thicker. The chrome film has good contact
`with the N+-type semIconductor layer dO.
`The chrome film fonns what
`IS called a
`barrier layer, which prevents alummum on
`the 2nd conductive layer, as mentioned later,
`from
`spreading
`to
`the
`N+-type
`semiconductor
`layer
`dO. For
`the
`1st
`
`conductive layer, refractory (Mo, Ti, Ta. W)
`
`film and refractory metal silicide (MoSi~.
`TiSI~. TaSi~. WSJ2) can be used mstead of
`the chrome.
`IS
`the 1st conductive layer dl
`After
`patterned by photo processing, N+-type
`semiconductor layer dO is removed using a
`mask for photo processing or
`the
`1st
`
`conductive layer dl as a mask; That is. the
`N+-type semiconductor layer dO remaining
`
`on the i-type semiconductor layer AS is
`
`removed from Iht: iayer except for the 1st.
`conductive layer d 1 USlDg self-alignment.
`
`this point. the N+-type semiconductor
`At
`layer dO is ctchoJ to be completely remo\'l:l1
`by the thickness, which causes the i-type
`semiconductor
`layer AS to be slightly
`etched on the surface: the etching level can
`be controllt:d by etching time
`Aftenvards, the 2nd conductive layer d2
`is fonned to be approximately 3.000 to
`5.500 A thick (appTOx. 3,500 Atluck in the
`device) by sputtering using aluminum.
`Aluminum film has
`less
`StTt:SS than
`chrome film, allowing thicker film to be
`
`formed. and is designed to reduce resistance
`the
`values of the source electrode SOl,
`drain electrode SO~, and the picture signal
`wire OL. The :!nd conductive Idyer d2 is
`designed to enhance the speed of thin·film
`transistor TFf performance and to er1hance
`signaling speed of the picture signal DL
`the 2nd conductive layer d2
`That
`is.
`Improves tht: writing characteristic of the
`picture elements For the 2nd conductive
`layer d2, aluminum Infused With such
`
`CMO 0183110
`
`Exhibit 1006, page 7
`
`

`

`r
`
`titaniwn,
`
`additives as sihcon, palladIUm.
`and cuprum (eu) can be used
`the 2nd conductive layer d2 is
`After
`pattemed by photo processing,
`the 3rd
`conductive layer d3 is fonned to be
`approxImately 300 to 1,400 Athick (approx.
`1,200 thick in the liquid crystal deVIce)
`using a transparent conducting film (ITO:
`
`necessary film) formed by sputtering. The
`3rd conductive film dJ constitutes
`the
`source electrode SOl. the drain electrode
`SO:!, and the picfure signal wire OL as well
`as the transparent picture electrode ITO.
`
`The 1st conductive layer dl on the source
`e1ectrodc SOl
`and that 00 the drain
`electrode SO:! are larger in the channel
`formation areas compared to the 2nd
`conductive layer d2 and the 3rd conductive
`layer 113 in the upper layers. That is, the 1st
`conductive layer dl is designed to be larger
`than the .:!nd conductive layer d2 and the
`3rd conductive layer d3 (the 1st conductive
`layer dl to the 3rd conductive layer d3 may
`be aligned on the line in their channel
`
`forming areas) when the masks do not
`match in the manufacturing processes of the
`1st conductive layer dl, 2nd conductive
`
`layer d2. and Jrd conductive layer dJ. Both
`the 1st conducti\'e layer on the source
`electrode SO I
`and that on the drain
`electrode SD2 arc designed to determine
`the gate length L of the thm-film transistor
`TFT.
`Thus, divided thin-film transistors TFTI
`to TFT 3 in the picture elements each have
`the Ist conductive layer d I larger than the.
`
`2nd conductive layer dl and the
`Jrd
`conductive
`layer
`d3
`in
`the
`channel
`formation areas on source electrode SDI
`and
`the dram electrode
`SO.:!. which
`length L of
`the
`determines
`the gate
`thm-film transIstor based on the size of the
`space between the 1st conductive layer dl
`on the source electrode SO I and that on the
`drain electrode S02. The space between the
`1st conductive layers (gate length) can be
`determined by the processing accuracy
`
`allows
`which
`accuracy).
`(patternIng
`thin-film transistors TFTI to TFT3 to have
`the same gate length
`as
`IS,
`electrout: SDI
`The
`source
`the
`to
`mentioned
`above,
`connected
`transparent pIcture element electrode lID.
`The source electrode SO I is placed along
`the steps on the i-type semiconductor layer
`AS (steps equivalent to the total of adding
`the thicknesses of the Ist conductive layer
`gl, N+-type semiconductor layer dO, and
`i-type semiconductor
`layer AS) More
`specifically,
`the source electrode SOl
`is
`constItuted of the Ist conductive layer d I
`
`being formed along the steps on the i-type
`semIconductor
`layer
`AS,
`the
`::!nd
`conductive layer d2 being formed smaller
`than and on the above la yer where it
`is
`cOlmected to the transparerIt picture element
`electrode ITO, and the .3rd conductive layer
`d3 being connected to the 1st conductive
`layer dl exposed from the 2nd conductive
`layer d2. The 1~t eondue ri ve layer on the
`to the
`source electrode SOl adheres well
`N+-type semiconductor layer dO, and it is
`
`CMO 0183111
`
`Exhibit 1006, page 8
`
`

`

`from
`layer
`barrier
`tht:
`as
`desIgned
`substances spread mainly from the 2nd
`conductive
`layer d2 Because the
`1st
`conductive layer d I cannot l.TOSS over the
`steps on the i-type semiconductor layer AS,
`because the chrome film stress-which
`increases
`as
`the
`layer
`becomes
`thicker-does not allow a thick layer. the
`2nd conductive layer d2 on the source
`e1cctrode SDI is designed to cross over the:
`steps on i-type semiconductor layer AS
`That is, the thick 2nd conductive layer d2
`increases the step coverage Being formed
`layer d2
`thIckly.
`the 2nd conductive
`significantly contributes to reducing the:
`resistance value of the source electrode d2
`(same for the drain electrode SD2 and the
`picture signal wue DL). The 3rd conductive
`layer d3 is connected to the 1st conductive
`layer dl exposed when the size of the 2nd
`conductive layer d2 is made smaller.
`because the 3rd conductive layer d3 cannot
`cross over the steps that are attributed to the
`i-type semiconductor layer AS on the 2nd
`conductive layer. The 1st conductive layer
`d I and the 3rd conductive layer d3 do not
`only adhere well
`to each other but also
`securely connect with each other, as the
`steps in the connection area in between are
`small.
`the source electrode SOlon the
`Thus,
`thm-film transistor TFT is constituted of at
`least a 1st conductive layer formed as the
`barrier layer along the i-type semiconductor
`layer AS. and a 2nd conductive layer d2
`formed on the Ist conductive layer, and has
`
`a lower resIstance value and smaller sue
`than the 1st conductive layer, and the 1st
`conductive layer being e~posed from the
`2nd conductive layer is connected to the 3rd
`conductive layer, which IS the transparent
`picture element electrode ITO, to secure the
`connection between the thin-film transistor
`TFT and the transparent picture element
`electrode ITO, which reduces dot defects
`attributed to disconnection. Furthermore,
`the source electrode SOl reduces resIstance
`value using the 2nd conductive layer d2 (an
`aluminum film), which
`has
`a
`lower
`
`resistance value for barrier effect brought
`by the 1st conductive layel dl.
`The drain electrode SD2 sharing a
`structure with the picture signal wire D1
`uses the same manufactunng process when
`formed. The dram electrodt: SD2 is placed
`vertically to form an L-shape crossing with
`IS,
`the
`the picture SIgnal wire DL That
`drain electrodes of all the divided thin-film
`to TIT3 in the picture
`transistors TIT I
`elements are connected to onc picture
`signal wIre DL.
`Said transparent pIcture ekctrode ITO is
`placed
`on each
`picture
`element
`and
`constitutes one of
`the picture element
`electrodes of the liquid crystal display
`device. The transparent picture dement
`electrode ITO is divided into three-ITO I,
`IT02,
`and
`IT03
`(divided transparent
`picture element electrode)--respectively. to
`to
`the divided thin-tilm transistors TITI
`picture
`element. The
`TFT3 m the
`transparent picturc element electrode ITOI
`
`CMO 0183112
`
`Exhibit 1006, page 9
`
`

`

`is connected to the source electrode SOlon
`thin-film transistor TFfl. The transparent
`ITO.!
`is
`picture
`element
`electrode
`connected to the source electrode SOl
`in
`thin-fihn transistor TFf:!. The transparent
`ITO 3
`is
`picture
`element
`electrode
`connected to the source electrode SOl
`in
`thin-film transistur TFf).
`element
`pIcture
`All
`the
`transparent
`electrodes ITOI to IT03 have substantively
`the same size as the thin-film transistors
`TFT) to TFT 3. All the transparent picture
`element electrodes ITOI to [T03 share one
`i.type semiconductor
`layer AS (all
`the
`diVlded
`thin-film transistors TFT are
`gathered to one location), which forms the
`L-shape.
`Thus, the thin-film transistor TFT in the
`piclUre element, which is located within a
`crossover area~where the neighboring two
`scanning
`signal wires GL and
`Ihe
`neighbonng two picture signal wires OL
`cross each other-IS diVIded into a plurality
`of thin-film transistors TITI to TFT3. and
`transparent picture element electrodes ITOI
`to IT03 being divided respectively to
`Ihm-film transistors TIT I
`to TFT3 are
`connected to the thin-film tranStstors, which
`allows dot defects only where the pictule
`element
`is divided (thin-film transistor
`TFTl,
`for example) and allows no dot
`defect in the picture element overall (nu dut
`defect in the thin-film transistors TFTI to
`TFT3), reducing dot defects in the picture
`elemcrtt overall.
`Also. smce said divided picture element
`
`with dot defects is smaller than the overall
`area of the picture e1ementl.one third of the
`picture element area), said dot defects are
`hardly visible overall.
`In addition. the transparent picture element
`electrodes ITOI
`to [TOJ,
`substantively
`having the same result 10 the dot defect
`areas. are the same size in the pIcture
`elements.
`Also. by maktng the size of transparent
`picture element electrodes ITO I to lT03
`
`is possible to
`It
`the substantially same,
`make the Cpix and Cgs uniform, where
`Cpi'{ is capacitance for the liquid crystal
`consisting of each of transparent picture
`element electrodes ITOI to IT03 and the
`common
`transparent
`picture
`element
`electrode ITO. and Cgs is superposition
`c.:tpacitance derived by superposmg the
`transparcrtt picture element electrodes ITO I
`10 IT03 and the gate electrode GT. which is
`imposed onto each of
`the transparent
`pIcture element electrodes ITOI
`to lT03.
`That is. all the transparent picture element
`electrodes ITO I to ITO 3 have the same
`liquid crystal capacitance and the same
`superposition capacitance, whIch evens the
`duect current components to be imposed on
`liquid
`crystals
`allnbuled
`to
`the
`SUperposItion· capacitance
`and
`reduces
`variance 10 the direct current components
`unposed on the hquid crystals in the piclUre
`elements when adopting a method of
`canceling the direct current components.
`A protectIOn film PSV)
`is placed on the
`thin film transistor TFT and the transparent
`
`CMO 0183113
`
`Exhibit 1006, page 10
`
`

`

`upper
`
`transparent glass
`
`Also, a backlight can be Installed on the
`substrate SUB!
`while the lower transparent glass substrate
`SUBI is used for observation (exposed to
`
`the
`
`outside).
`
`In
`
`such
`
`case.
`
`the
`
`light-shielding film LS serves as a shield
`
`against the backlight and the gate electrode
`OT serves as a shield agamst natural light.
`
`When a positive bias is imposed on the gate
`electrode aT in the thin film transistor TFT,
`
`the channel resistance between the source
`
`and drain is reduced. When the bias is set to
`
`zero, the channel resistance becomes larger
`
`That is, the thin film transistor is designed
`
`picture
`
`element
`
`electrode
`
`ITO.
`
`The
`
`protection film PVS is formed mainly to
`the thin film transistor TFT from
`protect
`moisture,
`and
`a
`tughly
`transparent,
`moisture--resistant material is used for the
`
`film. The protectIOn' film PSV forms to be
`an approximately 5000 to 11000 [A] thick
`(appro~l1nately 8000 [A]tltick in the Iil{uid
`crystal display device) siltcon oxide film or
`a silicon nitride layer formed by plasma
`CVD, for example. On the upper part of the
`protection' film' PSVI on the thin film
`transistor TFT, a light-shielding film LS is
`placed
`to
`prevent outside
`light
`from
`
`rt
`
`entering the i-type semiconductor layer AS
`
`to control
`
`the voltage Imposed on the
`
`used as the channel
`
`formation area. A.s
`
`shown in FIG. 2. the light-shielding film LS
`
`is placed over the area encircled by the dot
`line The Itght-shielding film LS IS formed
`to be an approximately 1000 [A]
`aluminum film or chrome film, for example.
`using a sputtering technique.
`
`thick
`
`the
`between
`located
`being
`Thus,
`light-shielding film LS and the slightly
`large gate electrode OT located both on and
`
`under the layer. the common semiconductor
`layer AS shared among the thin film
`transistors TFTI to TFT3 is blocked from
`
`outside natural
`
`light. The light-shielding
`
`transparent picture element electrode ITO.
`The Itquid crystals LC are positioned and
`sealed on a lower orientation film ORI I and
`an upper orientation film ORIl, which
`
`determine where the liqUId crystals are
`oriented within the space formed between
`the lower transparent glass substrate SUB I
`
`and the upper transparent glass substrate
`SUB2.
`The lower orientation film ORII is formed'
`
`on the upper part of the protection film
`
`lower
`
`the
`on
`PSV I
`substrate SUB I
`On the inner surface (liquid crystals) of the
`
`transparent glass
`
`film LS and the gate electrode aT are
`
`upper transparent glass substrate SUB1. a
`
`formed to be slightly larger
`
`than the
`
`semiconductor layer AS and In a similar
`
`color filter FIL, a protection film PSV2. the
`common
`transparent
`picture
`element
`
`shape. The two have the same' size (in the
`
`electrode CCOM)
`
`ITO,
`
`and the upper
`
`the gate electrode OT is depicted
`figure,
`slightly smaller than the light shielding film
`lS to make the boundary recogniz;ablel.
`
`orientation film ORl:! are layered in that
`order.
`Said common transparent picture element
`
`CMO 0183114
`
`Exhibit 1006, page 11
`
`

`

`electnxle: ITO is oriented to the transparent
`
`performed to form a red filter R. Next,
`
`picture element electrode ITO placed on
`
`followmg the sante process, a green filter G
`
`each
`
`picture
`
`element
`
`on
`
`the
`
`lower
`
`and
`
`a
`
`blue
`
`filter
`
`B are
`
`formed
`
`transparent glass substrate and shares the
`
`consecuti vely
`
`structure: with
`
`the:
`
`other
`
`neighboring
`
`Thus. each of the color filters flL is formed
`
`common
`
`transparent
`
`picture
`
`element
`
`in the Junction opposing each picture
`
`electrodes The common transparent picture
`element electrode ITO is designed 10 havl: a
`
`element such that the scannmg signal wire
`
`GL and the picture signal wire DL cross
`
`common
`
`voltage Vcom imposed. The
`
`between each of the color
`
`filters FIL,
`
`common voltage Vcom is in the midrange
`
`potential betwttO a low-level drive voltage
`
`secunng extra space
`positions
`(increases
`
`adjustmg the
`for
`the margin
`for
`
`Vdmin and a high-level drive voltage
`
`adjusting the POSItIOns) of the different
`
`VdIruix. which are apphed to. the picture
`
`colored filters in the area where the wires
`
`signal wire DL.
`
`eXIst. Furthermore.
`
`it also secures extra
`
`The color
`
`filter FIL is constituted of a
`
`space for adjusting the positions when
`
`coloring base material. which is made of a
`
`forming each of the color filters FIL
`
`resin material such as acrylic resin, which is
`
`That IS, in the liquid crystal dIsplay device,
`
`colored The color filter FlL IS placed on
`each picture element
`in the area opposite
`
`the picture element is placed in the junction
`between the netghboring two scanning
`
`from the picture element. which are colored
`
`signal wires GL and the neighboring two
`
`the
`is.
`differently from one another. That
`color filter FIL is placed witlun the jlDlctlon
`
`picture signal wires DL. and the picture
`element
`is divided into the plurality of
`
`where the netghboring two scanning signal
`
`e1emet1ts. where each of the color filters
`
`wires GL and the neighboring two picturl:
`signal wires DL lTOSS wuh each other. as in
`
`FIL is fonned in the location opposIte from
`
`the pIcture element. thereby reducing said
`
`the picture element. The picture element is
`
`dot defects while securing extra space for
`
`divided in to a plurality in which each of
`
`adjusting the positions between the picture
`
`the filters has a specIfic color.
`
`elemet1ts and the colored filters.
`
`The color
`
`filter FIL can be fanned as
`
`The protection film PSVl
`
`IS placed to
`
`follows. First, a coloring base material
`
`IS
`
`prevent
`
`the coloring used for dying said
`
`formed on the
`
`surface of
`
`the
`
`upper
`
`color
`
`filters FlL different
`
`colors
`
`from
`
`transparent glass
`
`substrate SOO2.
`
`then
`
`leakll1g iuto dIe liquid crystals LC. The
`
`removed except for an area torming a red
`
`protectlOn film PSVl
`
`is,
`
`for example,
`
`filter, using a photolithography technique.
`
`constituted of
`
`such
`
`transparent
`
`resin
`
`The coloring base material is then