JP2012073518A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device with resistance against the strain applied from the outside.SOLUTION: A display device comprises: a substrate with a flat plane including a side in a first direction and a side in a second direction that is longer than the side in the first direction; a display portion on the substrate; and a display driver circuit for driving the display portion on the substrate, which includes a gate driver circuit formed using a thin film transistor, and a data driver circuit configured using an integrated circuit provided for a semiconductor substrate. The data driver circuit is disposed along the side of the substrate in the first direction, and the gate driver circuit is disposed along the side of the substrate in the second direction.

Description

The present invention relates to a display device, and more particularly to a display device formed on a flexible substrate.

Various display devices are used for various purposes, and are essential components in mobile terminals typified by mobile phones. Furthermore, it is also used for portable digital music players, IC cards, etc., and further miniaturization is required. On the other hand, new display devices such as organic EL and electronic paper have been put into practical use, and development of flexible display devices has been promoted.

Accordingly, not only the display unit of the display device but also the display drive circuit is required to be further miniaturized and compatible with a flexible device. For example, Patent Document 1 describes a method of mounting a driver IC chip to drive a display in a display device. In addition, efforts are currently being made to build a display drive circuit on the same substrate with the same thin film transistor as the pixel circuit. In Patent Document 2, a driver IC chip is not directly fabricated and mounted on a silicon chip, but directly. A technique is described in which a thin film transistor that is the same as a pixel circuit is used and is directly formed on a substrate. Patent Document 3 describes that when an IC chip is mounted on an IC card, the aspect ratio of the outer shape of the IC chip is determined according to the vertical and horizontal bending stress ratio of the mounting position on the card. .

JP 2003-315760 A Japanese Patent No. 3944394 JP 2005-165814 A

However, in Patent Document 1, there is no problem as long as it is a rigid substrate such as glass as in the case of a normal liquid crystal display for a PC or a liquid crystal display for a portable terminal, but it may be bent like an IC card. In applications, there is a problem that the IC chip breaks due to distortion of the card. Further, Patent Document 2 has no problem in a simple circuit including only a shift register and a buffer driver like a gate driver, but includes a shift register and a buffer driver, a decoder, a LACH, a register, a controller, etc. like a data driver. In the case of such a complicated circuit, if even one transistor does not operate, there is a problem that the display device itself does not operate.

In view of the above circumstances, an object of the present invention is to provide a display device that is resistant to external distortion.

According to one embodiment of the present invention, a substrate having a plane composed of a side in the first direction, a side in the second direction longer than the side in the first direction, a display unit on the substrate, A display driver circuit for driving the display unit on the substrate, comprising: a gate driver circuit configured using thin film transistors; and a data driver circuit configured by an integrated circuit formed on a semiconductor substrate; The data driver circuit is disposed along a side of the base in the first direction, and the gate driver circuit is in the second direction of the base. A display device is provided that is arranged along a side.

The thin film transistor may be formed using an oxide semiconductor.

The base material may be a flexible substrate.

According to an embodiment of the present invention, there is provided an information recording medium including the display device, a memory for recording information, and a memory control circuit for controlling the memory.

According to the present invention, a display device having resistance to external distortion is provided.

It is a top view explaining the display apparatus 100 of the present invention according to one embodiment. 4 is a cross-sectional view of the display device 100. FIG. It is sectional drawing of the display apparatus 200 of this invention which concerns on one Embodiment. It is sectional drawing of the display apparatus 300 of this invention which concerns on one Embodiment.

Hereinafter, a display device and a manufacturing method thereof according to the present invention will be described with reference to the drawings. However, the display device of the present invention can be implemented in many different modes and should not be construed as being limited to the description of the embodiments and examples shown below. Note that in the drawings referred to in this embodiment mode and examples, the same portions or portions having similar functions are denoted by the same reference numerals, and repetitive description thereof is omitted.

As a result of intensive studies to solve the above-mentioned problems, it has been conceived that an integrated circuit (IC) is used for the data driver circuit and a display device is manufactured using a thin film transistor for the gate driver circuit. That is, when considering the base material that forms the display unit and the display drive circuit, it generally includes a side in the first direction (short direction) and a side in the second direction (longitudinal direction) that is longer than the first direction. These circuits are formed on a rectangular plane, and the side in the longitudinal direction is more easily bent than the side in the short direction. In addition, since the data driver circuit has a complicated circuit configuration, the data driver circuit is preferably formed using an IC chip rather than the same thin film transistor as the pixel circuit. Since the IC chip is formed on the semiconductor substrate, when the data driver circuit is formed using the IC chip, the display device is forced from the outside by being arranged along the short side of the substrate. In this case, since the distortion of the base material is smaller than the side in the longitudinal direction of the base material, the IC chip is difficult to break.

On the other hand, the gate driver circuit has a simpler circuit configuration than the data driver circuit, and thus can be formed using the same thin film transistor as the pixel circuit. Further, even if the data driver circuit is arranged with the thin film transistor along the side in the longitudinal direction of the base material, there is no fear of breaking like an IC chip. By forming the data driver circuit with a thin film transistor, a display device can be manufactured at a lower cost than using an IC chip, and there is no need to reinforce the side in the longitudinal direction of the display device. Therefore, in the display device according to the present invention, a data driver circuit formed of an IC chip is arranged on the same base material along a short side of the base material, and a gate driver circuit formed of a thin film transistor is provided on the base material. Arrange along the side in the longitudinal direction. The display device according to the present invention will be described in more detail with reference to examples.

(Embodiment 1)
The structure of the display apparatus 100 according to the first embodiment of the present invention will be described. FIG. 1 is a top view for explaining the structure of the display device 100 according to the present embodiment, and FIG. 2 is a cross-sectional view of the display device 100.

In the display device 100 according to the present embodiment, a display unit 110 and a display driver circuit that drives the display unit are arranged on an upper surface that is an element formation surface of a base material 101. The display driver circuit includes a data driver circuit 120 and a gate driver. A circuit 130 is included. The data driver circuit 120 is composed of an IC chip formed on the base material 101 and is arranged along the side of the base material 101 in the first direction (short direction). The gate driver circuit 130 is formed of a thin film transistor and is disposed along a side in the second direction (longitudinal direction). The data driver circuit 120 and the gate driver circuit 130 are connected to the display unit 110 through the wiring 140, respectively. When a power supply circuit, a memory for recording information, a control circuit (not shown), and the like are configured by an IC chip and arranged on the base material 101, the first direction (short direction) of the base material 101 Arranged along the side.

In the formation region of the display unit 110, the planarization layer 10, the gate electrode 51, the gate insulating film 20, the semiconductor layer 57, the source electrode 53 and the drain electrode 55, and the interlayer insulating film 30 are sequentially stacked on the upper surface of the base material 101. A thin film transistor is formed in a matrix shape, a transparent electrode 111 connected to the drain electrode 55 is disposed above the thin film transistor, and an alignment film 117, a liquid crystal layer, alignment films 117 and 113, and a transparent electrode 115 are sequentially stacked. A liquid crystal display unit is formed.

In the formation region of the data driver circuit 120, the pad 131, the bump 133, the electrode 135, and the IC chip 137 are sequentially stacked on the upper surface of the interlayer insulating film 30 to form the data driver circuit 120. Since the data driver circuit 120 has a more complicated circuit structure than the gate driver circuit 130, it is preferable to use the IC chip 137 rather than forming a thin film transistor. The data driver circuit 120 arranges the IC chip 137 along the side in the first direction (short direction) of the base material 101, so that even when a force is applied to the display device 100 from the outside, the data driver circuit 120 Since the distortion in the first direction is small, the IC chip 137 is not broken and can be used stably.

In the formation region of the gate driver circuit 130, a thin film transistor is formed in the same manner as the display unit 110, and the gate driver circuit 130 is configured. The gate driver circuit 130 has a simple structure, and even when a force is applied from the outside of the display device 100, the gate driver circuit 130 bends following the flexible base material 101, so that the circuit is not destroyed and is stable. It can be used.

A flexible substrate is used for the base material 101, and has flexibility such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and stainless steel (SUS) foil laminated with polyimide. Materials can be used. The thickness of the base material 101 can be appropriately selected within a range of 50 μm to 2 mm. By using a flexible substrate for the base material 101, the display device 100 can be bent in the second direction in which the gate driver circuit 130 is formed.

For the gate electrode 51, the source electrode 53, and the drain electrode 55, for example, indium tin oxide (ITO), zinc oxide (ZnO), indium zinc oxide (IZO), zinc oxide added with gallium (GZO), or the like is used. it can. Alternatively, a stack of titanium, aluminum, gold, copper, titanium, and aluminum can be used. As for the thickness of the gate electrode 51, the source electrode 53, and the drain electrode 55, 100 nm-300 nm are preferable.

For the gate insulating film 20 and the interlayer insulating film 30, for example, silicon oxide, silicon nitride, silicon oxynitride, or the like can be used. Further, a substrate made of a transparent organic resin such as a plastic substrate, a transparent film such as polypropylene, polyester, vinyl, polyvinyl fluoride, vinyl chloride, polyester, and polyamide may be used. The thicknesses of the gate insulating film 20 and the interlayer insulating film 30 can be appropriately selected within a range of 100 nm to 3 μm.

The semiconductor layer 57 can be formed using an oxide semiconductor containing zinc oxide (ZnO) as a main component. When ZnO is the main component, in addition to intrinsic oxide zinc, p-type dopants such as lithium (Li), sodium (Na), nitrogen (N) and carbon (C), and boron, if necessary (B), zinc oxide doped with n-type dopants such as aluminum (Al), gallium (Ga), indium (In), and zinc oxide doped with magnesium (Mg), beryllium (Be), etc. It may be. Further, the semiconductor layer 57 may be formed of an oxide semiconductor such as indium oxide added with tin (indium tin oxide: ITO), indium zinc oxide (IZO), or magnesium oxide (MgO). The thickness of the semiconductor layer 57 can be appropriately selected within the range of 20 nm to 100 μm. By forming a thin film transistor using an oxide semiconductor, the gate driver circuit 130 can be sufficiently driven.

The display unit 110 may have the same configuration as that of a known liquid crystal display device. For example, the transparent electrode 111 and the transparent electrode 115 may include tin oxide (Zinc oxide: ZnO) and indium tin oxide (ITO). ) Etc. can be used. In addition, a known configuration such as a polarizing film can be arranged as necessary. Note that an information recording medium may be configured by arranging a control circuit, a memory, and the like on the same substrate 101 in the display device 100 of the present invention.

As described above, the display device 100 according to the embodiment of the present invention uses a silicon IC chip for a data driver circuit having a complicated structure and a thin film transistor for a gate driver circuit having a simple structure. The outstanding effect which can improve the yield of the display apparatus 100 is show | played. Further, by disposing the data driver circuit using the IC chip in the short side direction of the flexible substrate where the display device 100 is difficult to bend, breakage of the IC chip can be suppressed. Furthermore, by disposing the gate driver circuit formed of the thin film transistor in the longitudinal direction of the flexible substrate, the gate driver circuit is not damaged even when the display device 100 is bent, and the yield is stabilized.

(Embodiment 2)
In the first embodiment, the liquid crystal display unit 110 has been described by taking the display device 100 as an example. In the present embodiment, the display device 200 in which an electroluminescence (EL) display unit 210 is disposed will be described. . In the second embodiment, an organic EL is described as an example, but the EL display unit 210 may be an inorganic EL.

In the display device 200, the data driver circuit 120 and the gate driver circuit 130 have the same configuration as that of the display device 100 of the first embodiment, and thus description thereof is omitted. In the formation region of the EL display unit 210, the planarization layer 10, the gate electrode 51, the gate insulating film 20, the semiconductor layer 57, the source electrode 53 and the drain electrode 55, and the interlayer insulating film 30 are sequentially stacked on the upper surface of the base material 101. Thus, a thin film transistor is formed in a matrix, an electrode 211 connected to the drain electrode 55 is disposed above the thin film transistor, and a light emitting layer 213 and a transparent electrode 215 are sequentially stacked to form an EL display unit 210.

The EL display unit 210 may have the same configuration as a known organic EL display device, and the electrode 211 is made of a conductive material that easily injects electrons, and is appropriately selected from a metal material, an organic material, and an inorganic compound. For example, Al, Cs, Er, etc. as a simple substance, MgAg, AlLi, AlLi, AlMg, CsTe, etc. as an alloy, Ca / Al, Mg / Al, Li / Al, Cs / Al, Cs ₂ O / Al, LiF as a laminate / Al, ErF ₃ / Al, and the like. The transparent electrode 115 is made of a conductive material that easily injects electrons, and is appropriately selected from metal materials, organic substances, and inorganic compounds. For example, tin oxide (Zinc oxide: ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), or the like can be used.

The material of the light emitting layer 213 is, for example, a cyclopentadiene derivative, a tetraphenylbutadiene derivative, a triphenylamine derivative, an oxadiazole derivative, a pyrazoloquinoline derivative, a distyrylbenzene derivative, a distyrylarylene derivative, or a silole. Derivatives, thiophene ring compounds, pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, coumarin derivatives, oxadiazole dimers, pyrazoline dimers, and the like. Examples of metal complex materials include aluminum quinolinol complexes, benzoquinolinol beryllium complexes, benzoxazole zinc complexes, benzothiazole zinc complexes, azomethyl zinc complexes, porphyrin zinc complexes, europium complexes, iridium metal complexes, platinum metal complexes, etc. The center metal has a rare earth metal such as Al, Zn, Be, Ir, Pt, etc., or Tb, Eu, Dy, etc., and the ligand is an oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structure, etc. And metal complexes having Specifically, tris (8-hydroxyquinolinolato) aluminum (Alq ₃ ) can be used. Examples of the polymer material include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyvinylcarbazole, polyfluorenone derivatives, polyfluorene derivatives, polyquinoxaline derivatives, polydialkylfluorene derivatives. , And copolymers thereof. Moreover, what polymerized said pigment-type material and metal complex-type material may be used.

Although not shown, a hole transport layer may be formed on the upper surface of the light emitting layer 213 and an electron transport layer may be formed on the lower surface. Furthermore, a hole injection layer may be formed on the upper surface of the hole transport layer, and an electron injection layer may be formed on the lower surface of the electron transport layer, or other configurations may be employed.

As described above, the display device 200 according to this embodiment of the present invention uses a silicon IC chip for a data driver circuit having a complicated structure as a display driver circuit for driving the EL display unit 210, and has a simple structure. By using a thin film transistor for the gate driver circuit, the yield of the display device 200 can be improved. Further, by disposing the data driver circuit using the IC chip in the short side direction of the flexible substrate where the display device 200 is difficult to bend, the breakage of the IC chip can be suppressed. Furthermore, by disposing the gate driver circuit formed of the thin film transistor in the longitudinal direction of the flexible substrate, the gate driver circuit is not damaged even when the display device 200 is bent, and the yield is stabilized. Such a configuration of the display driver circuit is suitable for an organic EL display that easily imparts flexibility to the entire display device. Note that an information recording medium may be configured by arranging a control circuit, a memory, and the like on the same substrate 101 in the display device 200 of the present invention.

(Embodiment 3)
In this embodiment, a display device 300 provided with a toner display type display unit 310 will be described as an example of application to electronic paper. In the third embodiment, a toner display method will be described as an example, but the display unit 310 may be a microcapsule electrophoresis twist ball method or an electronic powder fluid method.

In the display device 300, the data driver circuit 120 and the gate driver circuit 130 have the same configuration as that of the display device 100 of the first embodiment, and a description thereof will be omitted. In the formation region of the display portion 310, the planarization layer 10, the gate electrode 51, the gate insulating film 20, the semiconductor layer 57, the source electrode 53 and the drain electrode 55, and the interlayer insulating film 30 are sequentially stacked on the upper surface of the base material 101. A thin film transistor is formed in a matrix shape, an electrode 311 connected to the drain electrode 55 is disposed above the thin film transistor, and an insulating layer 317, a toner layer 313, an insulating layer 317, and a transparent electrode 315 are sequentially stacked, A display unit 310 is formed. Further, the display unit 310 may have a configuration other than these.

The display unit 310 may have the same configuration as a known electronic paper type, and the electrode 311 and the transparent electrode 315 are formed of a transparent conductive material, for example, a metal such as indium oxide, aluminum, gold, silver, or copper. , Conductive polymers such as polyaniline, polypyrrole and polythiophene.

The insulating layer 317 is preferably a flexible material, and examples thereof include polymer sheets such as polyethylene terephthalate, polyethersulfone, polyethylene, polycarbonate, polyimide, and acrylic.

As the particles used for the toner layer 313, a material having charging performance is used, and examples thereof include a resin, a charge control agent, a colorant, an inorganic additive, and the like, or a colorant alone. If it is resin, urethane resin, urea resin, acrylic resin, polyester resin, acrylic urethane resin, acrylic urethane silicone resin, acrylic urethane fluororesin, acrylic fluororesin, silicone resin, acrylic silicone resin, epoxy resin, polystyrene resin, styrene acrylic Resins, polyolefin resins, butyral resins, vinylidene chloride resins, melamine resins, phenol resins, fluororesins, polycarbonate resins, polysulfone resins, polyether resins, polyamide resins and the like can be mentioned, and two or more kinds can be mixed. In the case of a charge control agent, examples of the negative charge control agent include salicylic acid metal complexes, metal-containing azo dyes, metal-containing (including metal ions and metal atoms) oil-soluble dyes, quaternary ammonium salt compounds, calixes. Examples include allene compounds, boron-containing compounds (benzyl acid boron complexes), and nitroimidazole derivatives. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and the like. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide, ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives and salts thereof, various organic pigments, resins containing fluorine, chlorine, nitrogen, etc. are also charged. It can be used as a control agent. In the case of a colorant, examples of black pigments include carbon black, copper oxide, manganese dioxide, aniline black, and activated carbon. Yellow pigments include yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral first yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa yellow G, Hansa yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline There are yellow rake, permanent yellow NCG, tartrage rake and so on. Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK. Examples of red pigments include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risol red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin. Rake, Brilliant Carmine 3B, etc. Examples of purple pigments include manganese purple, first violet B, and methyl violet lake. Examples of blue pigments include bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, partially chlorinated phthalocyanine blue, first sky blue, and indanthrene blue BC. Examples of the green pigment include chrome green, chromium oxide, pigment green B, malachite green lake, final yellow green G, and the like. Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide. Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Examples of various dyes such as basic, acidic, disperse, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue. These colorants may be used alone or in combination.

As described above, the display device 300 according to the embodiment of the present invention uses a silicon IC chip for a data driver circuit having a complicated structure as a display driver circuit for driving the display unit 310, and is simple. By using a thin film transistor for the gate driver circuit having the structure, the yield of the display device 300 can be improved. Further, by disposing the data driver circuit using the IC chip in the short side direction of the flexible substrate where the display device 300 is difficult to bend, the breakage of the IC chip can be suppressed. Further, by disposing the gate driver circuit formed of the thin film transistor in the longitudinal direction of the flexible substrate, even if the display device 300 is bent, the gate driver circuit is not damaged and the yield is stabilized. Such a configuration of the display driver circuit is suitable for electronic paper that easily imparts flexibility to the entire display device. Note that an information recording medium may be configured by arranging a control circuit, a memory, and the like on the same base material 101 in the display device 300 of the present invention.

DESCRIPTION OF SYMBOLS 10 Planarization layer, 20 Gate insulating film, 30 Interlayer insulating film, 51 Gate electrode, 53 Source electrode, 55 Drain electrode, 57 Semiconductor layer, 100 Display apparatus, 101 Base material, 110 Display part, 111 Transparent electrode, 113 Liquid crystal layer 115 transparent electrode, 117 alignment film, 120 data driver circuit, 130 gate driver circuit, 131 pad, 133 bump, 135 electrode, 137 IC chip, 140 wiring, 200 display device, 211 electrode, 213 light emitting layer, 215 transparent electrode, 300 display device, 311 lower electrode, 313 particle layer, 315 transparent electrode, 317 insulating layer

Claims (4)

A substrate having a plane composed of a side in the first direction and a side in the second direction longer than the side in the first direction;
A display on the substrate;
A display driver circuit for driving the display unit on the substrate, comprising: a gate driver circuit configured using thin film transistors; and a data driver circuit configured by an integrated circuit formed on a semiconductor substrate; ,
A display device comprising:
The data driver circuit is disposed along a side of the base in the first direction, and the gate driver circuit is disposed along a side of the base in the second direction. A display device. The display device according to claim 1, wherein the thin film transistor is formed using an oxide semiconductor. The display device according to claim 1, wherein the base material is a flexible substrate. A display device according to any one of claims 1 to 3,
A memory for recording information;
A memory control circuit for controlling the memory;
An information recording medium having:

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