(12) United States Patent
`Kuribayashi et al.
`
`I 1111111111111111 11111 lllll 111111111111111 111111111111111 1111111111 11111111
`US006175345Bl
`US 6,175,345 Bl
`Jan.16,2001
`
`(10) Patent No.:
`(45) Date of Patent:
`
`(54) ELECTROLUMINESCENCE DEVICE,
`ELECTROLUMINESCENCE APPARATUS,
`AND PRODUCTION METHODS THEREOF
`
`(75)
`
`Inventors: Masaki Kuribayashi, Inagi; Yuichi
`Hashimoto; Akihiro Senoo, both of
`Tokyo; Kazunori Ueno, Ebina;
`Hidetoshi Tsuzuki, Yokohama, all of
`(JP)
`
`(73) Assignee: Canon Kabushiki Kaisha, Tokyo (JP)
`
`( *) Notice:
`
`Under 35 U.S.C. 154(b), the term of this
`patent shall be extended for O days.
`
`(21) Appl. No.: 09/084,994
`
`(22) Filed:
`
`May 28, 1998
`
`(30)
`
`Foreign Application Priority Data
`
`Jun. 2, 1997
`Jun. 10, 1997
`
`(JP) ................................................... 9-143836
`(JP) ................................................... 9-152309
`
`(51)
`
`Int. Cl.7 .............................. G09G 3/30; G09G 3/10;
`HOlL 31/00; H0lJ 1/62
`(52) U.S. Cl. ......................... 345/76; 315/169.3; 257/448;
`313/506
`(58) Field of Search ............................ 345/33-36, 44-45,
`345/55, 92, 76-81; 315/169.3; 313/500-520;
`257/59, 448; 349/42
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`4,006,383 *
`4,042,854 *
`4,356,429
`4,445,132 *
`4,539,507
`4,618,802
`4,720,432
`4,769,292
`4,776,676
`4,885,211
`4,904,989 *
`4,950,950
`4,954,747 *
`
`...................... 315/169 TV
`Luo et al.
`............................ 313/505
`Luo et al.
`Tang ..................................... 313/503
`Ichikawa et al. ...................... 357 /32
`Vanslyke et al.
`................... 313/504
`Schrank ............................... 313/512
`Van Slyke et al. .................. 428/457
`Tang et al. ........................... 428/690
`Inoue et al. . ... ... ... ... .... ... ... ... 350/350
`Tang et al. ........................... 428/457
`Matsui et al. .......................... 345/76
`Perry et al. .......................... 313/504
`Tuenge et al. ....................... 313/506
`
`2/1977
`8/1977
`10/1982
`4/1984
`9/1985
`* 10/1986
`1/1988
`9/1988
`10/1988
`12/1989
`2/1990
`8/1990
`9/1990
`
`9/1991 Vanslyke ............................. 313/503
`5,047,687
`10/1991 Littman et al. ...................... 313/503
`5,059,861
`10/1991 Vanslyke et al.
`................... 313/503
`5,059,862
`10/1991 Maskasky ............................ 430/569
`5,061,617
`12/1991 Scozzafava et al. ................. 428/323
`5,073,446
`5,079,483 * 1/1992 Sato .................................. 315/169.3
`5,151,629
`9/1992 Vanslyke ............................. 313/504
`5,294,869
`3/1994 Tang et al. ........................... 313/504
`5,294,870
`3/1994 Tang et al. ........................... 313/504
`5,302,966 * 4/1994 Stewart .................................. 345/76
`5,539,424 * 7/1996 Hattori et al.
`......................... 345/76
`5,670,792 * 9/1997 Utsugi et al. .......................... 257/59
`5,684,365 * 11/1997 Tang et al. ........................ 315/169.3
`5,714,968 * 2/1998 Ikeda ...................................... 345/77
`5,844,362 * 12/1998 Tanabe et al.
`....................... 313/506
`
`FOREIGN PATENT DOCUMENTS
`
`0 349 265
`1/1990 (EP) .
`6-136360
`5 /1994 (JP) .
`6-188074
`7 /1994 (JP) .
`6-192654
`7 /1994 (JP) .
`6-256759
`9 /1994 (JP) .
`8-41452
`2/1996 (JP) .
`8-241048
`9 /1996 (JP) .
`* cited by examiner
`
`Primary Examiner-Vijay Shankar
`Assistant Examiner-Jeff_ Piziali
`(74) Attorney, Agent, or Firm-Fitzpatrick, Cella, Harper &
`Scinto
`
`(57)
`
`ABSTRACT
`
`An electroluminescence device having a transistor substrate
`comprising drain electrode pads, each being connected to a
`drain of a thin film transistor, and capacitors connected to the
`respective drain electrode pads, and an electroluminescence
`substrate comprising pairs of electrodes and electrolumines(cid:173)
`cence members each provided between a pair of electrodes,
`arranged along a plurality of rows and columns, wherein the
`thin film transistor substrate and the electroluminescence
`substrate are placed opposite to each other so that the drain
`electrode pads and the electroluminescence members are
`opposed to each other, and wherein each drain electrode pad
`and one electrode of a pair of electrodes are connected
`through an adhesive electric connection member.
`
`30 Claims, 7 Drawing Sheets
`
`23
`'v
`
`24
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`U.S. Patent
`
`Jan.16,2001
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`Sheet 1 of 7
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`US 6,175,345 Bl
`
`FIG. 1
`
`Xi SOURCE
`LINE
`
`Xi+1
`
`Xi+2
`
`,-- ---------------- --------
`
`GROUND BUS
`
`24
`
`FIG. 2
`
`Yj
`
`Yj+1
`
`23
`
`21
`
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`22
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`
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`U.S. Patent
`
`Jan.16,2001
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`Sheet 2 of 7
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`US 6,175,345 Bl
`
`FIG. 3
`34
`
`24
`
`22
`33
`32
`31
`
`FIG. 4
`
`22
`33
`
`31
`
`42
`
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`U.S. Patent
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`Jan.16,2001
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`Sheet 3 of 7
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`US 6,175,345 Bl
`
`FIG. 5
`
`-- 6
`
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`I
`6
`
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`U.S. Patent
`
`Jan.16,2001
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`Sheet 4 of 7
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`US 6,175,345 Bl
`
`FIG. 7
`72
`
`71
`
`24
`
`FIG. 8
`
`83
`
`61
`51
`
`22
`33
`32
`31
`
`82'
`
`81
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`U.S. Patent
`
`Jan.16,2001
`
`Sheet 5 of 7
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`US 6,175,345 Bl
`
`FIG. 9
`
`. SOURCE
`X
`1 LINE
`
`Xi+1
`
`Xi+2
`
`Yj+1
`
`GEL
`
`REL
`
`GEL
`
`BEL
`
`BEL
`
`FIG. 12
`
`121
`
`511
`
`---------------------------------------- □ RB1
`□ □ □ ---------------------------------------- □ RB2
`
`512
`
`GATE
`ARRAY
`
`□ □ □ ---------------------------------------· □ RBn
`
`51n
`
`VR
`REVERSE BIAS
`POTENTIAL
`
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`U.S. Patent
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`Jan.16,2001
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`Sheet 6 of 7
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`US 6,175,345 Bl
`
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`U.S. Patent
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`Jan.16,2001
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`Sheet 7 of 7
`
`US 6,175,345 Bl
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`US 6,175,345 Bl
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`1
`ELECTROLUMINESCENCE DEVICE,
`ELECTROLUMINESCENCE APPARATUS,
`AND PRODUCTION METHODS THEREOF
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`The present invention relates to an electroluminescence
`device and an electroluminescence apparatus applicable to
`display devices, light-emitting sources, or printer heads of
`electrophotographic printers, and methods for producing
`them. More particularly, the invention relates to a device and
`an apparatus using organic electroluminescence members
`suitable for full-color display of large screen, and methods
`for producing them.
`2. Related Background Art
`The known organic electroluminescence members are, for
`example, those disclosed in Japanese Laid-Open Patent
`Applications No. 6-256759, No. 6-136360, No. 6-188074,
`No. 6-192654, and No. 8-41452.
`It is also known that these organic electroluminescence
`members are driven by thin film transistors, for example, as
`described in Japanese Laid-Open Patent Application No.
`8-241048.
`For driving the organic electroluminescence members by
`the thin film transistors, an organic electroluminescence
`member had to be mounted per drain electrode pad of thin
`film transistor, however. Particularly, in the case of the
`full-color display, the electroluminescence members of three
`kinds for electroluminescence emission of the three primary 30
`colors, blue, green, and red, had to be patterned on a thin film
`transistor substrate. Since the thin film transistor surface had
`greater unevenness than thin films of the electrolumines(cid:173)
`cence members, it was difficult to pattern the thin films of
`electroluminescence members in high definition and high
`density. A further problem was that productivity was low,
`because the two types of functional devices, the transistors
`and electroluminescence members, were concentrated on the
`thin film transistor substrate.
`The organic electroluminescence members had a further
`problem that long-term application of de voltage thereto
`shortened continuous emission time. Particularly, when they
`were driven by the thin film transistors disclosed in Japanese
`Laid-Open Patent Application No. 8-241048 etc., there arose
`a problem that the de voltage was continuously applied to
`the organic electroluminescence members, so as to promote
`deterioration of the organic electroluminescence members.
`
`2
`tors connected to the respective drain electrode pads; and an
`electroluminescence substrate comprising pairs of elec(cid:173)
`trodes and electroluminescence members interposed
`between the pairs of electrodes, which are arranged along a
`5 plurality of rows and columns, wherein said thin film
`transistor substrate and electroluminescence substrate are
`placed opposite to each other so that the drain electrode pads
`and the electroluminescence members are opposed to each
`other, and wherein each drain electrode pad is connected
`10 through an adhesive electric connection member to one of a
`pair of electrodes.
`Second, the present invention has the second feature of an
`electroluminescence device having a transistor substrate
`comprising first thin film transistors arranged along a plu-
`15 rality of rows and columns, gate lines provided for the
`respective rows, each gate line being a common line for
`connecting gates of first thin film transistors on one of the
`rows, source lines provided for the respective columns, each
`source line being a common line for connecting sources of
`20 first thin film transistors on one of the columns, second thin
`film transistors each connected to a drain of the respective
`first thin film transistors, and capacitors connected to the
`respective second thin film transistors, wherein a gate of
`each second thin film transistor is connected to the drain of
`25 the first thin film transistor, a drain electrode pad is con(cid:173)
`nected to a drain of each second thin film transistor, and a
`source of each second thin film transistor is connected to one
`electrode of the capacitor; and an electroluminescence sub(cid:173)
`strate comprising pairs of electrodes and electrolumines-
`cence members interposed between the pairs of electrodes,
`which are arranged along a plurality of rows and columns,
`wherein said thin film transistor substrate and electrolumi(cid:173)
`nescence substrate are placed opposite to each other so that
`the drain electrode pads and the electroluminescence mem-
`35 bers are opposed to each other, and wherein each drain
`electrode pad is connected through an adhesive electric
`connection member to one of a pair of electrodes.
`Third, the present invention has the third feature of a
`production method of electroluminescence device compris-
`40 ing steps of: preparing a transistor substrate comprising thin
`film transistors arranged along a plurality of rows and
`columns, gate lines provided for the respective rows, each
`gate line being a common line for connecting gates of thin
`film transistors on one of the rows, source lines provided for
`45 the respective columns, each source line being a common
`line for connecting sources of thin film transistors on one of
`the columns, drain electrode pads each connected to a drain
`of the respective thin film transistors, and capacitors con(cid:173)
`nected to the respective drain electrode pads; preparing an
`50 electroluminescence substrate comprising pairs of elec(cid:173)
`trodes and electroluminescence members interposed
`between the pairs of electrodes, which are arranged along a
`plurality of rows and columns; placing an adhesive electric
`connection member on at least one of the drain electrode
`55 pads of the transistor substrate and the electroluminescence
`members; and overlaying the thin film transistor substrate on
`the electroluminescence substrate opposite to each other so
`that the drain electrode pads and the electroluminescence
`members are opposed to each other.
`Fourth, the present invention has the fourth feature of a
`production method of electroluminescence device compris(cid:173)
`ing steps of: preparing a transistor substrate comprising thin
`film transistors arranged along a plurality of rows and
`columns, gate lines provided for the respective rows, each
`65 gate line being a common line for connecting gates of thin
`film transistors on one of the rows, source lines provided for
`the respective columns, each source line being a common
`
`SUMMARY OF THE INVENTION
`
`An object of the present invention is to provide a device
`using organic electroluminescence members suitable for
`full-color display of large screen, solving the above
`problems, and a production method thereof.
`Another object of the present invention is to provide an
`electroluminescence apparatus capable of continuous emis(cid:173)
`sion over the long term.
`First, the present invention has the first feature of an
`electroluminescence device having a transistor substrate
`comprising thin film transistors arranged along a plurality of 60
`rows and columns, gate lines provided for the respective
`rows, each gate line being a common line for connecting
`gates of thin film transistors on one of the rows, source lines
`provided for the respective columns, each source line being
`a common line for connecting sources of thin film transistors
`on one of the columns, drain electrode pads each connected
`to a drain of the respective thin film transistors, and capaci-
`
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`US 6,175,345 Bl
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`3
`line for connecting sources of thin film transistors on one of
`the columns, drain electrode pads each connected to a drain
`of the respective thin film transistors, and capacitors con(cid:173)
`nected to the respective drain electrode pads; preparing an
`electroluminescence substrate comprising pairs of elec(cid:173)
`trodes and electroluminescence members interposed
`between the pairs of electrodes, which are arranged along a
`plurality of rows and columns; placing an adhesive electric
`connection member on at least one of the drain electrode
`pads of the transistor substrate and the electroluminescence
`members; placing an adhesive electric insulator around the
`periphery of the adhesive electric connection member on at
`least one of the drain electrode pads of the transistor
`substrate and the electroluminescence members; and over(cid:173)
`laying the thin film transistor substrate on the electrolumi(cid:173)
`nescence substrate opposite to each other so that the drain
`electrode pads and the electroluminescence members are
`opposed to each other.
`Fifth, the present invention has the fifth feature of a
`production method of electroluminescence device compris(cid:173)
`ing steps of: preparing a transistor substrate comprising thin
`film transistors arranged along a plurality of rows and
`columns, gate lines provided for the respective rows, each
`gate line being a common line for connecting gates of thin
`film transistors on one of the rows, source lines provided for 25
`the respective columns, each source line being a common
`line for connecting sources of thin film transistors on one of
`the columns, drain electrode pads each connected to a drain
`of the respective thin film transistors, and capacitors con(cid:173)
`nected to the respective drain electrode pads; preparing an 30
`electroluminescence substrate comprising pairs of elec(cid:173)
`trodes and electroluminescence members interposed
`between the pairs of electrodes, which are arranged along a
`plurality of rows and columns; placing an adhesive electric
`connection member on at least one of the drain electrode 35
`pads of the transistor substrate and the electroluminescence
`members; placing an adhesive electric insulator around the
`periphery of the adhesive electric connection member on at
`least one of the drain electrode pads of the transistor
`substrate and the electroluminescence members; overlaying 40
`the thin film transistor substrate on the electroluminescence
`substrate opposite to each other so that the drain electrode
`pads and the electroluminescence members are opposed to
`each other; and evacuating a space between the thin film
`transistor substrate and the electroluminescence substrate
`and heating the adhesive electric connection member and
`adhesive electric insulator to cure said member and insula-
`tor.
`Sixth, the present invention has the sixth feature of an
`electroluminescence apparatus having first switching
`devices arranged along a plurality of rows and columns, first
`wires provided for the respective rows, each first wire being
`a common wire for connecting first terminals of first switch(cid:173)
`ing devices on a row, second wires provided for the respec(cid:173)
`tive columns, each second wire being a common wire
`connecting second terminals of first switching devices on a
`column, electroluminescence elements, each having one
`electrode connected to a third terminal of a first switching
`device, other electrode, and an electroluminescence member
`interposed between the one and other electrodes, capacitors
`connected to the respective third terminals, second switch(cid:173)
`ing devices, each being provided between one electrode of
`an electroluminescence element and a third terminal of a
`first switching device, third wires connected to the one
`electrodes of the electroluminescence elements, third 65
`switching devices disposed in the third wires, and driving
`means, said driving means applying a first on signal pulse
`
`4
`for turning the first switching devices on, to a first wire of
`a predetermined row, applying a first off signal pulse for
`turning the first switching devices off, to the first wires of the
`other rows, applying an information signal pulse of a for-
`5 ward bias voltage according to information, to the second
`wires in synchronism with the first on signal pulse, and
`applying a second on signal pulse for turning the second
`switching devices on, to a control line for the second
`switching devices over a predetermined period in, before, or
`10 after application of the first on signal pulse for said prede(cid:173)
`termined row, thereby activating writing into each electrolu(cid:173)
`minescence member on said row; then said driving means
`applying a second off signal pulse for turning the second
`switching devices off, to said control line after the prede-
`15 termined period, applying a third on signal pulse for turning
`the third switching devices on, to a control line for the third
`switching devices in, before, or after application of the
`second off signal pulse, thereby actuating reverse bias apply(cid:173)
`ing means set so that a reverse bias voltage is placed
`20 between said third wire and the other electrodes of the
`electroluminescence elements.
`Seventh, the present invention has the seventh feature of
`an electroluminescence apparatus having first thin film tran(cid:173)
`sistors arranged along a plurality of rows and columns, first
`wires provided for the respective rows, each first wire being
`a common wire for connecting gates of first thin film
`transistors on a row, second wires provided for the respec(cid:173)
`tive columns, each second wire being a common wire for
`connecting sources of first thin film transistors on a column,
`electroluminescence elements, each having one electrode
`connected to a drain of a first thin film transistor, other
`electrode, and an electroluminescence member interposed
`between the one and other electrodes, second thin film
`transistors connected at gates thereof, each being provided
`between said drain and one electrode of the electrolumines(cid:173)
`cence element, capacitors connected to the respective drains,
`first switching devices, each being provided between one
`electrode of an electroluminescence element and a drain
`electrode of a second thin film transistor, third wires, each
`being connected to one electrode of an electroluminescence
`element, second switching devices provided in said third
`wires, and driving means, said driving means applying a first
`on signal pulse for turning the first thin film transistors on,
`to a first wire of a predetermined row, applying a first off
`45 signal pulse for turning the first thin film transistors off, to
`the first wires of the other rows, applying an information
`signal pulse of a forward bias voltage according to
`information, to the second wires in synchronism with the
`first on signal pulse, and applying a second on signal pulse
`50 for turning the first switching devices on, to a control line for
`the first switching devices over a predetermined period in,
`before, or after application of the first on signal pulse for said
`predetermined row, thereby activating writing into each
`electroluminescence member on said row; then said driving
`55 means applying a second off signal pulse for turning the first
`switching devices off, to said control line after the prede(cid:173)
`termined period, and applying a third on signal pulse for
`turning the second switching devices on, to a control line for
`the third switching devices in, before, or after application of
`60 the second off signal pulse, thereby actuating reverse bias
`applying means set so that a reverse bias voltage is placed
`between said third wire and the other electrodes of the
`electroluminescence elements.
`Eighth, the present invention has the eighth feature of an
`electroluminescence apparatus having: switching devices
`arranged along a plurality of columns and rows, first wires
`provided for the respective rows, each first wire being a
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`5
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`5
`common wire for connecting first terminals of switching
`devices on a row, second wires provided for the respective
`columns, each second wire being a common wire for con(cid:173)
`necting second terminals of switching devices on a column,
`and electroluminescence elements, each having one elec(cid:173)
`trode connected to a third terminal of a switching device,
`other electrode, and an electroluminescence member inter(cid:173)
`posed between the one and other electrodes; and driving
`means, said driving means applying a scanning selection
`pulse for selecting at least one row out of said plurality of
`rows, to a first wire corresponding to the selected row,
`applying an information signal pulse for bringing the elec(cid:173)
`troluminescence members into a forward bias state accord-
`ing to information, to each of the second wires in synchro(cid:173)
`nism with the scanning selection signal, and applying a bias 15
`voltage for bringing the electroluminescence members into
`a reverse bias state, through a third wire to the electrolumi(cid:173)
`nescence members before start of application of a next
`scanning selection signal or a scanning selection signal
`thereafter to the first wire corresponding to said selected
`row.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is an equivalent circuit diagram of an EL device of
`the present invention;
`FIG. 2 is a plan view of an EL pixel on the TFT substrate
`side, used in the EL device of the present invention;
`FIG. 3 is a sectional view along line 3-3 in FIG. 2;
`FIG. 4 is a sectional view along line 4--4 in FIG. 2:
`FIG. 5 is a plan view of an EL pixel on the EL substrate
`side, used in the EL device of the present invention;
`FIG. 6 is a sectional view along line 6-6 in FIG. 5;
`FIG. 7 is a sectional view of an EL device of the present
`invention;
`FIG. 8 is a sectional view of an evacuation system used
`in the method of the present invention;
`FIG. 9 is an equivalent circuit diagram of another EL
`device of the present invention;
`FIG. 10 is an equivalent circuit diagram of an EL appa(cid:173)
`ratus used in another embodiment of the present invention;
`FIG. 11 is a timing chart of driving used in the present
`invention; and
`FIG. 12 is a plan view of an EL substrate used in the
`present invention.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`The electroluminescence members are preferably media
`that emit the three primary colors of blue, green, and red;
`particularly, organic electroluminescence members.
`The adhesive electric connection member is preferably a
`material in which electrically conductive particles are dis(cid:173)
`persed in an adhesive, and particularly preferably, a material
`containing a silane coupling agent.
`It is preferable to employ a bond structure in which an
`adhesive electric insulator is disposed around the periphery
`of the adhesive electric connection member.
`The thin film transistors are preferably of a polysilicon
`semiconductor, a crystal silicon semiconductor, a microc(cid:173)
`rystal silicon semiconductor, or an amorphous silicon semi(cid:173)
`conductor.
`At least one electrode out of a pair of electrodes on either
`side of the electroluminescence member is preferably a
`transparent electrode of ZnO having the texture structure.
`
`6
`The sixth, seventh, and eighth features of the present
`invention permit the alternating voltage to be applied to the
`electroluminescence elements in active matrix driving,
`thereby greatly extending the continuous emission time of
`the organic electroluminescence members over the long
`term in particular.
`The predetermined period used in the present invention is
`a period equal to ¼ to ¾ of one vertical scanning period ( one
`frame period or one field period), preferably a period equal
`10 to 1/3 to 2/3 thereof, and particularly optimally, a period equal
`to approximately ½ thereof.
`A time average voltage of the forward bias voltage and
`reverse bias voltage used in the present invention is prefer(cid:173)
`ably set to approximately zero.
`The present invention will be described by reference to
`the drawings. In the following description, the thin film
`transistor described above will be denoted by "TFT" and the
`electroluminescence member by "EL."
`FIG. 1 is a schematic diagram of an active matrix four-
`20 terminal TFT-EL device. A device of each pixel includes two
`TFTs, a storage capacitor, and an EL device. A principal
`feature of the four-terminal type is the capability of sepa(cid:173)
`rating an addressing signal from an EL excitation signal. The
`EL device is selected through the logic TFT (Tl) and
`25 excitation power to the EL device is controlled by the power
`TFT (T2). The storage capacitor makes it possible to keep
`the excitation power staying in the addressed EL device once
`selected. Thus the circuit permits the EL device to operate at
`the duty cycle close to 100%, ignoring the time assigned to
`30 addressing.
`Gate lines Yp Yj+l are preferably a lot of wires, for
`example 640 wires or 1120 wires, to which gate pulses are
`applied in order. The gate pulses may be of either interlace
`scanning or non-interlace scanning.
`Source lines X;, X;+i, X;+2 are preferably a lot of wires,
`for example 840 wires or 1280 wires, to which information
`signal pulses of a voltage set according to image data are
`applied in synchronism with the gate pulses.
`In the drawing REL designates red-emitting EL, GEL
`40 green-emitting EL, and BEL blue-emitting EL; information
`signal pulses of red are applied to the source line X;, green
`information pulses to X;+i, and blue information pulses to
`X;+2 · This achieves the full-color display.
`FIG. 2 is a plan view to show a typical example of TFT
`substrate 3 according to the present invention. TFT 1 cor(cid:173)
`responds to Tl of FIG. 1, TFT 2 to T2 of FIG. 1, capacitor
`21 to Cs of FIG. 1, and drain electrode pad 22 to an electrode
`connected to the drain of T2 in each EL of FIG. 1.
`FIG. 3 is a sectional view along line 3-3 in FIG. 2. FIG.
`4 is a sectional view along line 4-4 in FIG. 2.
`TFT 1 and TFT 2 used in the present invention have such
`transistor structure that source bus 24 is connected to n+
`polysilicon, the drain to n+ polysilicon, PECVD (plasma-
`55 enhanced CVD)-SiO 2 film 32 is placed as a gate insulating
`film on either side of the i-type polysilicon film, and the gate
`bus is connected to n+ polysilicon. Reference numeral 31
`refers to a base substrate.
`The present invention is not limited to the aforementioned
`60 transistor structure, but may adopt either the stagger struc(cid:173)
`ture or the coplanar structure using amorphous silicon or
`microcrystalline silicon semiconductors.
`The present invention can be applied to MOS transistors
`of the SOI (silicon on insulator) structure using crystal
`65 silicon.
`The capacitor Cs is composed of a pair of capacitor
`electrodes 41 and 42, and SiO2 film 33 interposed between
`
`35
`
`45
`
`50
`
`SAMSUNG EX. 1003 - 11/16
`
`

`

`US 6,175,345 Bl
`
`7
`the pair of capacitor electrodes as shown in FIG. 4. The
`capacitor electrode 41 is a film formed of Al or the like and
`connected to the ground bus 25, while the capacitor elec(cid:173)
`trode 42 is a film formed of n+ polysilicon and connected to
`the drain of TFT 2.
`
`5
`
`The gate bus 23 and source bus 24 are preferably
`chromium/aluminum layered wires.
`
`A passivation film 34 is preferably a film of silicon nitride
`formed by plasma CVD.
`
`10
`
`8
`
`A metal film of aluminum, silver, or the like can be used
`as the drain electrode pad 22 in order to provide it with
`reflecting performance, but a transparent conductive film
`such as ITO or ZnO may also be applied.
`
`FIG. 5 is a plan view of EL substrate 6 used in the present
`invention and FIG. 6 is a sectional view along line 6-6 in
`FIG. 5.
`
`The EL substrate 6 is composed of glass substrate 61, a
`pair of electrodes disposed on the glass substrate 61, i.e., a
`transparent electrode 51 and an EL electrode pad 62 of
`aluminum or the like forming a reflecting surface, and the
`EL interposed between the pair of electrodes.
`
`The EL 52 is preferably an organic EL; particularly, either
`one of those forming REL, GEL, and BEL is placed.
`
`Specific examples of REL, GEL, and BEL are listed
`below, but it is noted that the present invention is not
`intended to be limited to these examples and that inorganic 30
`ELs can also be applied instead of the organic ELs.
`
`15
`
`In the above formula, Q represents Nor C-R (where R is
`hydrogen, alkyl, or halogen), Mis a metal, a metal oxide, or
`a metal halide, and Tl, T2 represent hydrogen or both make
`up an unsaturated six-membered ring containing a substitu(cid:173)
`ent such as alkyl or halogen. A preferred alkyl part contains
`20 approximately one to six carbon atoms, while phenyl com(cid:173)
`poses a preferred ary 1 part.
`In a preferred embodiment the hole migration layer is
`aromatic tertiary amine. A preferred subclass of the aromatic
`tertiary amine contains tetraaryldiamine having the follow-
`25 ing formula.
`
`Rs
`R7
`'
`I
`N-Are-N
`/
`\
`n
`AR
`
`R9
`
`Materials applicable as the organic ELs in the present
`invention are those disclosed, for example, in Scozzafava's
`EPA 349,265 (1990); Tang's U.S. Pat. No. 4,356,429;
`VanSlyke et al.'s U.S. Pat. No. 4,539,507; VanSlyke et al.'s
`U.S. Pat. No. 4,720,432; Tang et al.'s U.S. Pat. No. 4,769,
`292; Tang et al.'s U.S. Pat. No. 4,885,211; Perry et al.'s U.S.
`Pat. No. 4,950,950; Littman et al.'s U.S. Pat. No. 5,059,861;
`VanSlyke's U.S. Pat. No. 5,047,687; Scozzafava et al.'s U.S.
`Pat. No. 5,073,446; VanSlyke et al.'s U.S. Pat. No. 5,059,
`862; VanSlyke et al.'s U.S. Pat. No. 5,061,617; VanSlyke's
`U.S. Pat. No. 5,151,629; Tang et al.'s U.S. Pat. No. 5,294,
`869; Tang et al.'s U.S. Pat. No. 5,294,870. The EL layer is
`comprised of an organic hole injection and transporting zone
`in contact with the anode, and an electron injection and
`transporting zone which forms a junction with the organic
`hole injection and transporting zone. The hole injection and
`transporting zone is made of a single material or plural
`materials, and comprises a hole injection layer in contact
`with the anode and a contiguous hole transporting layer
`interposed between the hole injection layer and the electron
`injection and transporting zone. Similarly, the electron injec(cid:173)
`tion and transporting zone is made of a single material or
`plural materials, and comprises an electron injecting layer in
`contact with the cathode and a contiguous electron trans(cid:173)
`porting layer that is interposed between the electron injec(cid:173)
`tion layer and the hole injection and transporting zone.
`Recombination of hole and electron and luminescence
`occurs in the electron injection and transporting zone adja-
`cent to the junction b