1. Field of the Invention
This invention relates to a display device which can be manufactured with a low cost, and a manufacturing method of a display device which can manufacture a display device with a low cost.
2. Description of the Related Art
Conventionally, when producing a display element for use in a display device, a semiconductor fabrication process is used to form a semiconductor circuit for driving the display element, on a substrate, such as a glass substrate, and form an insulating layer on the semiconductor circuit, and further form the display element on the insulating layer. Namely, the semiconductor circuit for driving the display element and the display element are formed one by one by laminating such films on the glass substrate.
For this reason, as disclosed in Japanese Laid-Open Patent Application No. 2004-104134, it is necessary to form a thick interlayer insulation film after the semiconductor circuit is formed, and it is necessary to form a through hole for electrically connecting the semiconductor circuit and the display element, in the thus formed interlayer insulation film.
When forming an interlayer insulation film using an inorganic material, such as SiO2 or Si3N4, sputtering or CVD (chemical vapor deposition) method is used as the film forming method. However, such vacuum processes require a number of processes. Also, when an organic semiconductor material is used as a semiconductor material, a plasma process must be used as the process of forming the interlayer insulation film. The use of the plasma process may damage the organic semiconductor material, and it is difficult to obtain sufficient characteristics.
Moreover, when forming a through hole, etching, such as RIE (reactive ion etching), must be performed. The use of the RIE may damage the organic semiconductor material, and it is difficult to obtain predetermined characteristics.
In order to eliminate the problem, Japanese Laid-Open Patent Application No. 2007-103484 discloses a method of forming an interlayer insulation film by a screen printing, in which a mixture of fine particles and an organic material is used as the interlayer insulation film.
However, when the wet-type film forming method is performed, the interlayer insulation film must be formed after a driver part including a semiconductor chip is formed, as disclosed in Japanese Laid-Open Patent Application No. 2007-103484. Specifically, when a wet-type spreading of an insulating material solved in an organic solvent is performed and a semiconductor material for forming the semiconductor chip is easily eroded by the organic solvent, the semiconductor material will be adversely influenced by the organic solvent. It is difficult to obtain sufficient characteristics of the semiconductor chip formed by the semiconductor material.
Furthermore, heating is usually needed to form an interlayer insulation film. When a semiconductor material for forming the semiconductor chip is vulnerable to heating, the semiconductor chip will be adversely influenced by heating. It is difficult to obtain sufficient characteristics of the semiconductor chip.
Furthermore, formation of the interlayer insulation film or the through hole is performed after the driver part including the semiconductor chip is formed. For this reason, it takes much time to perform a manufacturing process including a series of processes, and the productivity will be reduced.
Furthermore, a display part is usually formed after the driver part including the semiconductor chip is formed. When the process of forming the display part includes a step of heating or UV irradiation and the semiconductor material which is easily damaged by heating or UV irradiation must be used, it is difficult to obtain sufficient characteristics of the semiconductor chip formed by the semiconductor material.
Furthermore, a pattern of electrodes is formed on the interlayer insulation film after the interlayer insulation film is formed. The interlayer insulation film which is adversely influenced by the supporting semiconductor layer may have surface irregularities. If the electrodes are formed on the surface irregularities of the interlayer insulation film, occurrence of a disconnection or formation of a high resistance region may take place, which causes a defective semiconductor chip to be produced. A conceivable method for eliminating surface irregularities is a CMP (chemical mechanical polishing) method. However, even if the CMP method is performed to make the surface of the interlayer insulation film flat, there is a possibility that the semiconductor layer be damaged by the CMP method. In addition, the number of processes will be increased and the manufacturing time will be increased by the use of the CMP method.
In the case of the method disclosed in Japanese Laid-Open Patent Application No. 2007-103484, the semiconductor material may be adversely influenced by the organic solvent used to mix the organic material with the fine particles, which will affect the characteristics of the semiconductor chip.
In one aspect of the invention, the present disclosure provides an improved display device in which the above-described problems are eliminated.
In one aspect of the invention, the present disclosure provides a display device which is able to be manufactured with good quality and low cost, without adversely affecting the semiconductor material and the semiconductor chip, and raise the productivity.
In an embodiment of the invention which solves or reduces one or more of the above-mentioned problems, the present disclosure provides a display device comprising: a first substrate on which a semiconductor circuit is formed; a second substrate disposed over the first substrate to include a first electrode formed on a first surface of the second substrate to perform image displaying, and a second electrode exposed to a second surface of the second substrate and bonded to the first electrode via a contact hole; a third substrate disposed over the second substrate to include a third electrode formed to perform image displaying in association with the first electrode of the second substrate; and an image displaying layer formed between the second substrate and the third substrate to perform image displaying, wherein an electrode on a surface of the first substrate on which the semiconductor circuit is formed is electrically connected to the second electrode exposed to the second surface of the second substrate.
In an embodiment of the invention which solves or reduces one or more of the above-mentioned problems, the present disclosure provides a display device comprising: a first substrate on which a semiconductor circuit is formed; a second substrate disposed over the first substrate to include a first electrode formed on a first surface of the second substrate to perform image displaying, a second electrode exposed to a second surface of the second substrate and bonded to the first electrode via a contact hole, and a connection electrode being flush with the second electrode in a different position on the second surface and formed to be connected to an electrode on the first substrate; and an image displaying layer disposed on the first electrode of the second substrate to perform image displaying with the first electrode and an opposing electrode disposed on the image displaying layer, wherein electrodes on a surface of the first substrate on which the semiconductor circuit is formed are electrically connected to the second electrode and the connection electrode on the second surface of the second substrate respectively.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.
A description will be given of embodiments of the invention with reference to the accompanying drawings.
A first embodiment of the invention will be described. This embodiment relates to a method of manufacturing an electrophoretic display device.
Specifically, as shown in
In the FET 12, the gate (G) is connected to a gate line 15, the source (S) is connected to a signal line 14, and the drain (D) is connected to both one electrode of the image displaying element 11 and one electrode of the pixel capacitor 13. Both the other electrode of the image displaying element 11 and the other electrode of the pixel capacitor 13 are grounded.
In the drive circuit, the voltage supplied from the signal line 14 according to the gray scale of each pixel, and the gate voltage from the gate line 15 used as the scanning line for supplying the signal voltage to the gate (G) of each FET 12 are sequentially supplied to and scanned over the respective pixels, so that the displaying of the respective pixels is carried out.
The pixel capacitor 13 has the function to maintain the gray scale signal during a period of one scan, and the capacitance of the pixel capacitor 13 varies depending on the interval between two of the scans.
Next, the manufacturing process of the display device of this embodiment will be described.
The drive circuit of the display device of this embodiment includes three substrates 21, 31, and 41 in which respective electrodes are formed thereon. For the sake of convenience, a description of the region in which the pixel capacitor is formed will be omitted.
First, as shown in
A desired material which can be used for the gate electrode 22 is at least one chosen from the group including a metal, such as Cr (chromium), Ta (tantalum), Ti (titanium), Cu (copper), Al (aluminum), Mo (molybdenum), W (tungsten), Ni (nickel), Au (gold), Pd (palladium), Pt (platinum), Ag (silver), Sn (tin), any of their alloys, a transparent electrode material made of ITO, indium oxide or zinc oxide, a polyacethylene base conductive polymer material, a polyphenylene base conductive polymer material, such as polyparaphenylene or its dielectric, polyphenylene vinylene or its dielectric, a heterocyclic base conductive polymer material, such as polypyrole or its dielectric, polythiophene or its dielectric, polyfuran or its dielectric, and an ionic conductive polymer material, such as polyaniline or its dielectric.
One of the above-mentioned conductive polymers may be subjected to doping with a suitable dopant so as to obtain a higher conductivity. It is desirable to use a dopant having a low vapor pressure for the above-mentioned doping. A desired material of the dopant is any of polysulfone acid, polystyrene sulfonate, naphthalene sulfonic acid, alkyl naphthalene sulfonic acid, etc. A metal, an alloy, or a conductive polymer may be used together with the dopant in this embodiment. A desired material of the gate electrode that can be used for the second substrate 31 and the third substrate 41 (which will be described later) is the same as the above-mentioned material for the first substrate 21.
The method of forming the gate electrode in this embodiment is a vacuum film deposition process, such as vacuum evaporation, sputtering, or CVD. After the film of the metallic material of the electrode is deposited in the whole surface, the application of a photoresist, the prebaking, the exposure by an exposure device, and the developing are performed so that a resist is formed in the region used as an electrode pattern. Then, the etching of the formed resist pattern, such as RIE (reactive ion etching), is performed so that the gate electrode is formed. Alternatively, the electrode forming method may be any of the ink jet method using an ink-like conductive material, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, etc. In the case of forming the electrode by printing, the electrode can be formed quickly with a low cost. Furthermore, the electrode may be formed by metal plating. In the case of the metal plating, it is possible to form a thin electrode film with a low resistance using a simple processing unit. The metal plating is advantageous when it is intended to increase the electrode film thickness.
In this manner, the gate electrode 22 is formed on the first substrate 21 as shown in
Next, as shown in
The method of forming the gate insulating layer 23 in this embodiment is any of the vacuum deposition method, such as vacuum evaporation, sputtering, or CVD, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, the anode oxidation method, the spin coat method, the dipping method, the spray coat method, the ink jet method, etc.
In this manner, the gate insulating layer 23 is formed to cover the gate electrode 22 formed on the first substrate 21 as shown in
Next, as shown in
Next, as shown in
The method of forming the semiconductor layer 26 in this embodiment is the vacuum film deposition process, such as vacuum evaporation, sputtering, or CVD. After the film of the semiconductor material is deposited in the whole surface, the application of a photoresist, the prebaking, the exposure by an exposure device, and the developing are performed so that a resist is formed in the region used as a semiconductor layer. Then, the etching of the formed resist pattern, such as RIE (reactive ion etching), is performed so that the semiconductor layer is formed. Alternatively, the semiconductor layer forming method may be any of the ink jet method using an ink-like conductive material, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, etc. In the case of forming the semiconductor layer 26 by printing, the application of a photoresist and the exposure process using the exposure device may be omitted, and the semiconductor layer 26 can be formed with a low cost in a short time.
Next, through a manufacturing process that is separate from the above-mentioned manufacturing process, the portion of the display device of this embodiment which is used as an image displaying element is produced. A description will be given of this manufacturing process with reference to
As shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Alternatively, in another embodiment, the second substrate 31 and the third substrate 41 may be bonded together such that the electrode 35a on the second substrate 31 faces the electrode 42 on the third substrate 41, and thereafter the image displaying layer 36 may be formed.
Next, the electrode 24 formed in the first substrate 21 on which the semiconductor chip used as the drive circuit is formed as shown in
Next, as shown in
Thereby, the image display device which includes the three substrates 21, 31, and 41 is produced.
When the surface on which the third substrate 41 is formed is a visual recognition side of the display device, it is necessary to form the electrode 42 formed in the third substrate 41 and the third substrate 41 with a transparent material so as to make the substrate 41 and the electrode 42 transparent.
When the surface on which the first substrate 21 is formed is a visual recognition side of the display device, it is necessary to make the driver element formed in the first substrate 21 and the first substrate 21 transparent.
The drive circuit is formed in the first substrate 21, and the image displaying layer 36 which constitutes the image displaying element is formed in the third substrate 41. When the materials of the drive circuit and the image displaying layer 36 easily deteriorate due to the influence of the moisture or the atmosphere, it is necessary to improvement the passivation performance. It is preferred to form, in the inside or the outside of the first substrate 21 and the third substrate 41, a thin film of a material with low permeability to moisture or O2 (oxygen), such as Si3N4.
In this embodiment, the film of Si3N4 is formed on the surfaced of the first substrate 21 and the third substrate 41 and the adhesive layer is formed between the respective substrates, although it is not illustrated. The display device of this embodiment has the structure for preventing the inclusion of moisture or oxygen.
In the above embodiment, the anisotropic conduction film 28 is used. Alternatively, another bonding method may be used.
As shown in
Next, as shown in
Next, the electrode 24 formed in the first substrate 21 in which the semiconductor chip used as the drive circuit shown in
It is also possible to stick electrode 24 of the first substrate 21 and electrode 35b of the second substrate 31 directly, and to take electric junction, without forming the solder layer 37.
On the other hand, as for the surface of electrode 35b formed in the contact hole used as a junction area, being processed to a rough surface it is preferred that when taking the electric connection of the electrode of the first substrate 21, and electrode 35b formed of the contact hole of the second substrate 31, without using anisotropic conduction film 28.
Specifically, roughing of the surface is performed by dipping this portion in an etching solution short time. Because the image display device of this embodiment does not need to form an interlayer insulation film, it can be formed in a low-temperature process, and it can be manufactured for a short time, without having a bad influence on a semiconductor chip.
Because the electrode is formed in the surface of each substrate, it becomes possible to eliminate the defect which does not form an electrode pattern on an interlayer insulation film, and originates in high resistance of disconnection or wiring.
Next, a second embodiment of the invention will be described. This embodiment relates to a method of manufacturing an electrophoretic display device. The composition of a drive circuit for driving the electrophoretic display device of this embodiment is shown in
Specifically, as shown in
In the FET 112, the gate (G) is connected to the gate line 115, the source (S) is connected to the signal line 117, and the drain (D) is connected to both the gate (G) of the FET 113 and the electrode of the pixel capacitor 114. The electrode of another side of the pixel capacitor 114 is connected to the capacitor line 116.
In the FET 113, the source (S) is connected to the driver line 118, and the drain (D) is connected to one electrode of the display element 111. The electrode of another side of the display element 111 is grounded.
Next, the manufacturing process of the display device of this embodiment will be described.
The drive circuit of the display device of this embodiment includes three substrates in which respective electrodes are formed. For the sake of convenience, a description of the region in which the pixel capacitor is formed will be omitted.
As shown in
A desired material of the first substrate 121 in this embodiment is an inorganic insulating material, such as SiO2, or an organic insulating material, such as polyimide resin, styrene resin, polyethylene base resin, polypropylene, vinyl chloride base resin, polyester alkyd resin, polyamide, polyurethane, polycarbonate, polyarylate, polysulfone, diallyl phthalate resin, polyvinyl butyral resin, polyether resin, polyester resin, acrylic resin, silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, fluorine base resin (PFA, PTFE, PVDF, etc.), parylene resin, epoxy acrylate, a photo-curing resin (urethane-acrylate, etc.), polysaccharide or its dielectric, such as pullulan cellulose. The substrate 121 may be formed with a film of the above-mentioned material deposited on the surface of a film-like conductive material. It is preferred that the volume resistivity of the material of the substrate 121 of this embodiment is above 1×1013 Ω-cm. It is more preferred that the volume resistivity of the material of the substrate 121 of this embodiment is above 1×1014 Ω-cm. A desired material of the substrate that can be used as the second substrate 131 or the third substrate 141 (which will be described later) is the same as the above-mentioned material of the first substrate 121.
A desired material which can be used for the gate electrodes 122a and 122b is at least one chosen from the group including a metal, such as Cr (chromium), Ta (tantalum), Ti (titanium), Cu (copper), Al (aluminum), Mo (molybdenum), W (tungsten), Ni (nickel), Au (gold), Pd (palladium), Pt (platinum), Ag (silver), Sn (tin), any of their alloys, a transparent electrode material made of ITO, indium oxide or zinc oxide, a polyacethylene base conductive polymer material, a polyphenylene base conductive polymer material, such as polyparaphenylene or its dielectric, polyphenylene vinylene or its dielectric, a heterocyclic base conductive polymer material, such as polypyrole or its dielectric, polythiophene or its dielectric, polyfuran or its dielectric, and an ionic conductive polymer material, such as polyaniline or its dielectric.
One of the above-mentioned conductive polymers may be subjected to doping with a suitable dopant so as to obtain a higher conductivity. It is desirable to use a dopant having a low vapor pressure for the above-mentioned doping. A desired material of the dopant is any of polysulfone acid, polystyrene sulfonate, naphthalene sulfonic acid, alkyl naphthalene sulfonic acid, etc. A metal, an alloy, or a conductive polymer may be used together with the dopant in this embodiment. A desired material of the gate electrode that can be used for the second substrate 131 and the third substrate 141 (which will be described later) is the same as the above-mentioned material for the first substrate 121.
The method of forming the gate electrode in this embodiment is a vacuum film deposition process, such as vacuum evaporation, sputtering, or CVD. After the film of the metallic material of the electrode is deposited in the whole surface, the application of a photoresist, the prebaking, the exposure by an exposure device, and the developing are performed so that a resist is formed in the region used as an electrode pattern. Then, the etching of the formed resist pattern, such as RIE (reactive ion etching), is performed so that the gate electrode is formed. Alternatively, the electrode forming method may be any of the ink jet method using an ink-like conductive material, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, etc. In the case of forming the electrode by printing, the electrode can be formed quickly with a low cost. Furthermore, the electrode may be formed by metal plating. In the case of the metal plating, it is possible to form a thin electrode film with a low resistance using a simple processing unit. The metal plating is advantageous when it is intended to increase the electrode film thickness.
In this manner, as shown in
Next, as shown in
The method of forming the gate insulating layers 123a and 123b in this embodiment is any of the vacuum deposition method, such as vacuum evaporation, sputtering, or CVD, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, the anode oxidation method, the spin coat method, the dipping method, the spray coat method, the ink jet method, etc.
In this manner, the gate insulating layers 123a and 123b are formed to cover the surface of the gate electrodes 122a and 122b on the first substrate 121 as shown in
Next, as shown in
The electrodes 125a, 125b, 125c, and 125d are electrodes which are used as the drain (D) and the source (S) of each FET, by forming semiconductor layers thereon in the next step.
Specifically, after a metallic film of Cu etc. is formed on the whole surface of the substrate 121 on which the gate insulating layers 123a and 123b are formed, by sputtering, a photoresist is applied and the exposure by the exposure device, and the development are performed so that a resist pattern is formed on the electrodes where the drain and the source are formed. Next, the metallic film in the region in which the resist is not formed is removed by RIE, and the resist is finally removed with an organic solvent, so that the electrodes 124a, 124b, 125a, 125b, 125c, and 125d are formed.
Next, as shown in
The electrodes 125a and 125b are electrodes for forming the drain and the source of the FET, and a channel is formed by the semiconductor layer 126a via the electrode 125a. Similarly, the electrodes 125c and 125d are electrodes for forming the drain and the source of the FET, and a channel is formed by the semiconductor layer 126b via the electrode 125d.
A desired material of the semiconductor layers 126a and 126b in this embodiment is any of an organic semiconductor material chosen from the group including fluorene, polyfluorene derivative, polyfluorenone, fluorenone dielectric, poly-N-vinylcarbazole dielectric, poly-γ-carbazolylethylglutamate dielectric, polyvinyl phenanthrene dielectric, polysilane dielectric, oxazole dielectric, oxadiazole dielectric, allylamine dielectrics, imidazole derivative, allylamine derivative (mono-allylamine, tri-allylamine derivative), benzidine dielectric, diallylmethane dielectric, tri-allylmethane dielectric, styrylanthracene derivative, pyrazoline dielectric, divinylbenzene dielectric, hydrazone derivative, indene dielectric, indenone dielectric, butadiene dielectric, pyrene formaldehyde, pyrene dielectric (polyvinyl pyrene), stilbene derivative (alpha-phenyl stilbene derivative, bis-stilbene derivative), enamine dielectric, and thiophene dielectric (poly-alkyl-thiophene dielectric, benzothieno-benzothiophene dielectric), an organic semiconductor material chosen from the group including pentacene, tetracene, bis-azo or tris-azo base coloring matter, poly-azo base coloring matter, triallylmethane base coloring matter, thiadin base coloring matter, oxadin base coloring matter, xanthene base coloring matter, cyanine base coloring matter, styllyl base coloring matter, pyrylium base coloring matter, quinacridone base coloring matter, indigo base coloring matter, perylene base coloring matter, multi-ring quinone base coloring matter, bis-benz-imidazole base coloring matter, indanslone base coloring matter, squarylium base coloring matter, anthraquinone base coloring matter, porphyrin base coloring matter, and phthalocyanine base coloring matter (copper phthalocyanine, thitanile phthalocyanine), a compound semiconductor chosen from the group including CdS, ZnO, PbTe, PbSnTe, InGaZnO, GaP, GaAlAs, and GaN, and a silicon semiconductor material (polycrystalline silicon, amorphous silicone).
The method of forming the semiconductor layers 126a and 126b in this embodiment is the vacuum film deposition process, such as vacuum evaporation, sputtering, or CVD. After the film of the semiconductor material is deposited in the whole surface, the application of a photoresist, the prebaking, the exposure by an exposure device, and the developing are performed so that a resist is formed in the region used as a semiconductor layer. Then, the etching of the formed resist pattern, such as RIE (reactive ion etching), is performed so that the semiconductor layer is formed. Alternatively, the semiconductor layer forming method may be any of the ink jet method using an ink-like conductive material, the letterpress printing method, such as flexographic printing, the intaglio printing method, the screen printing method, the mimeographic printing method, the offset printing method, etc. In the case of forming the semiconductor layers 126a and 126b by printing, the application of a photoresist and the exposure process using the exposure device may be omitted, and the semiconductor layers 126a and 126b can be formed with a low cost in a short time.
Next, through a manufacturing process that is separate from the above-mentioned manufacturing process, the portion of the display device of this embodiment which is used as an image displaying element is produced. A description will be given of this manufacturing process with reference to
As shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
The electrodes 135 includes an electrode 135c used as an electrode 135b formed in that from which one surface serves as the electrode 135a of the display element, and a contact hole 132 formed on the other surface thereof, an electrode 135c used as driver line 118, and signal line 117. The electrodes 135b, 135c, and 135d surface is projected and formed rather than the surface of the second substrate 131, and serves as convex-like form.
Next, as shown in
The material which constitutes a liquid crystal display element besides the material from which image displaying layer 136 of this embodiment constitutes an electrophoretic display element, an electroluminescent (EL) display element, an electrochromic display element, an electrodeposition display element, etc. is mentioned.
Next, the electrodes 125b, 125a, and 125d formed in the first substrate 121 in which the semiconductor chip used as the drive circuit shown in
The electrode 135b formed in the contact hole of the second substrate 131, electrode 135c used as driver line 118, and 135d of electrodes used as signal line 117 are connected electrically. For this reason, an anisotropic conduction film 128 is formed on the surface on which the electrodes 125a, 125b, and 125d of the first substrate 121 are formed. The anisotropic conduction film 128 is formed by the method of covering the surface on which the electrodes 125a, 125b, and 125d of the first substrate 121 are formed by the anisotropic conduction sheet marketed, and the method of applying anisotropic conduction paste to this surface.
Next, by making the first substrate 121 and second substrate 131 stick by pressure, as shown in
The region 129b which electric conduction nature produced is formed, and electrode 125b of the first substrate 121 and electrode 135b formed in the contact hole of the second substrate 131 are connected electrically.
Similarly, the anisotropic conduction film 128 between electrode 125a of the first substrate 121 and electrode 135c of the second substrate 131 is stuck by pressure.
The region 129a which electric conduction nature produced is formed, and electrode 135c used as electrode 125a of the first substrate 121 and driver line 118 of the second substrate 131 is connected electrically.
Similarly, the anisotropic conduction film 128 between 125d of electrodes of the first substrate 121 and 135d of electrodes of the second substrate 131 is stuck by pressure.
The region 129c which electric conduction nature produced is formed, and 135d of electrodes used as 125d of electrodes of the first substrate 121 and signal line 117 of the second substrate 131 are connected electrically. Thereby, the display device which includes three substrates is produced.
When the surface on which the third substrate 141 is formed is a visual recognition side of a display, it is necessary to form electrode 142 formed in the third substrate 141 and third substrate 141 with a transparent base and a clear electrode.
When the surface on which the first substrate 121 is formed is a visual recognition side of a display, it is needed that the driver element formed in the first substrate 121 and first substrate 121 is transparent.
The drive circuit etc. is formed in the first substrate 121, and the third substrate 141, the image displaying layer 136 which constitutes a display element is formed, when the drive circuit and image displaying layer 136 use the material which deteriorates under the influence of moisture or the atmosphere. It is desirable to form the penetrable low thin film of the moisture of Si3N4 or O2 in the inside or the outside of the first substrate 121 and the third substrate 141 because of the improvement in passivation performance.
In this embodiment, although the graphic display has not been carried out, the film which consists of such Si3N4 grade is formed in the surface of the first substrate 121 and the third substrate 141, and between each substrates, it has pasted up with adhesives and has structure which prevented trespass of moisture or oxygen.
Next, in
The electrode 125a formed on the first substrate 121 and electrode 135c formed in the second substrate 131 are specifically set to the region 129a. The electrode 125d formed in the first substrate 121 and the electrode 135d formed in the second substrate 131 are set to the region 129c.
In the region 129b, by sticking anisotropic conduction film 128 by pressure respectively, conductivity arises and electrode 125b formed in the first substrate 121 and electrode 135b formed in the contact hole of the second substrate 131 are bonded.
Next, the junction composition of the first substrate 121 and the second substrate 131 will be described.
Connection of the first substrate 121 and the second substrate 131 is connected by shifting the second substrate 131 in the drawings, a sliding direction, and a horizontal direction, and connecting to the first substrate 121, as shown in
By connecting with such composition, the lead electrode 119 of the gate line 115, the capacitor line 116, the signal line 117, and the driver line 118 can be secured on the substrates of both the first substrate 121 and the second substrate 131.
By connecting with the first substrate 121 using the second somewhat small substrate 131 to the first substrate 121, as shown in
In the substrates of both the first substrate 121 and the second substrate 131, the lead electrode 119 of the gate line 115, the capacitor line 116, the signal line 117, and the driver line 118 can be secured. In this case, the signal line 117 formed in the second substrate 131 and the driver line 118 serve as the composition connected to the lead electrode 119 formed in the first substrate 121.
Because it is a uniform direction and lead electrode 119 can be formed on the same surface using the same composition, it becomes the composition of having been suitable for manufacture.
This lead electrode 119 is because it is formed in order to take the exterior and electric connection with the bonding method of a wire bond etc., and it is necessary to secure the work area in the case of connection enough.
Although this embodiment explained the case where anisotropic conduction film 128 is used, there is a method of using pewter as shown in
As shown in
The solder layer 137 is formed also in a part for the point of electrode 135c which similarly serves as driver line 118 formed in the second substrate 131, and 135d of electrodes used as signal line 117. This solder layer 137 may be formed by applying solder paste, even if it forms pewter.
Next, as shown in
The composition which does not have the third substrate 141 is also considered as other composition. In this case, the electrode is formed in two or more contact holes of the second substrate 131 and the first substrate 121 and second substrate 131 are fixed stably, and even if it is the composition of only an electrode, without having the third substrate 141, in a manufacturing process, it can manufacture satisfactorily, and as a manufacturing process, it becomes more advantageous than the first embodiment.
Next, the electrodes 125b, 125a, and 125d formed in the first substrate 121 in which the semiconductor chip used as the drive circuit shown in
The electrode 125b of the first substrate 121 and the electrode 135b formed at this time in the contact hole of the second substrate 131 are electrically connected by locally heating the surface on which the solder layer 137 is formed, and melting pewter of solder layer 137.
The electrode 135c which similarly serves as electrode 125a and the driver line 118 of the second substrate 131 which are formed in the first substrate 121 is connected electrically.
The electrode 135d used as the electrode 125d formed in the first substrate and the signal line 117 formed in the second substrate 131 are connected electrically.
Thereby, as shown in
On the other hand, when forming the electric connection of the electrodes of the first substrate 121 and the electrodes of the second substrate 131, without using the anisotropic conduction film 128, it is preferred to perform a surface roughing process to the surface of the electrodes 135b, 135c and 135d formed in the second substrate 121. Specifically, the surface roughing process is performed by dipping this portion in an etching solution for a short time.
Because the display device of this embodiment does not need to form an interlayer insulation film, it can be formed by a low-temperature process, and it can be manufactured in a short time without adversely influencing the semiconductor chip. Moreover, the electrodes are formed on the surface of each substrate, and it is possible to eliminate the defect caused by a disconnection of wiring or a high-resistance wiring, without forming any electrode pattern on the interlayer insulation film.
Next, the third embodiment of the invention will be described. The third embodiment is the TFT or the transistor which is applicable to the first substrate 21 or 121.
As for the TFT or the transistor of this embodiment, the first embodiment and the second embodiment are applicable. As for the TFT or the transistor in another composition, an embodiment of the invention is applicable.
Next, the fourth embodiment of the invention will be described.
The fourth embodiment is formation method with another electrode of the second substrate 31 and 131 about the first embodiment and second embodiment, and explains the case where an electrode is formed in what serves as the second substrate 131 of the second embodiment concretely.
First, as shown in
Next, as shown in
As for this resist pattern, it is desirable to form more thickly than the thickness of the electrode formed behind. It is possible to form the resist pattern of thickness which is different by both sides by making the spreading conditions and exposure conditions of resist into the conditions which differ by both sides.
Next, as shown in
Next, as shown in
The second substrate 331 in which this electrode 335 is formed is equivalent to what formed electrode 135 in the second substrate 131 of the second embodiment.
Because an electrode can be formed according to this embodiment, without performing etching, such as RIE, it is advantageous when forming an electrode thickly.
Next, the fifth embodiment of the invention will be described. The fifth embodiment is the case where an electrode is formed in the second substrate 131 using another formation method of the electrode of the second substrate 31 or 131, other than that used in the first embodiment and the second embodiment.
First, as shown in
Next, as shown in
Next, as shown in
By using the different conditions for printing at the time of performing the printing method for the two surfaces, it is possible to form the metal layer of different thickness.
There is the method of applying the nano metal ink by the ink jet method as a method of forming the electrodes 435 on both the surfaces of the second substrate 431 shown in
The second substrate 431 in which the electrodes 435 are formed is equivalent to the second substrate 131 of the second embodiment in which the electrode 135 is formed.
According to this embodiment, an electrode can be formed without performing the vacuum process, and a thicker electrode can be formed in a short time with a low cost.
Next, the sixth embodiment of the invention will be described. The sixth embodiment explains the case where an electrode is formed in what is another formation method of the electrode of the second substrate 31, and serves as the second substrate 31 of the first embodiment about the first embodiment.
First, as shown in
Next, as shown in
Next, as shown in
The second substrate 531 in which the electrode 535 is formed is equivalent to the second substrate 31 of the first embodiment in which the electrode 35 is formed.
According to this embodiment, an electrode can be formed without performed etching, such as RIE, and an electrode can be formed in a short time with a low cost.
Next, the seventh embodiment of the invention will be described. This embodiment relates to the composition in which the capacitor used as a pixel capacitor is produced simultaneously with the producing of a semiconductor chip in the second embodiment, and the transistor and the pixel capacitor are bonded together by bonding the first substrate and the second substrate.
A description will be given of the seventh embodiment of the invention with reference to
In this embodiment, the gate line 615 and the capacitor line 616 are formed in the first substrate 621, and the electrode 635a of the display element is formed in the second substrate 631.
By compressing the anisotropic conduction film 628 by pressure, conductivity is given to the region 629a in which the electrode 625a formed on the first substrate 621 and the electrode 635c formed on the second substrate 631 are bonded and electrically connected together, conductivity is given to the region 629c in which the electrode 625d formed on the first substrate 621 and the electrode 635d formed on the second substrate 631 are bonded and electrically connected together, and conductivity is given to the region 629b in which the electrode 625b formed on the first substrate 621 and the electrode 635b formed in the contact hole of the second substrate 631 are bonded and electrically connected together. Similarly, conductivity is given to the regions 629e and 629d in which the electrode 624c and the electrode 625c formed on the first substrate 621 are bonded and electrically connected to the electrode 635e, so that the capacitor used as the pixel capacitor 643 is formed. Thereby, the gate electrode 622a of the first transistor 641 is connected to both the second transistor 642 and the pixel capacitor 643 in the region 629f.
The capacitor used as the pixel capacitor 643 is constituted by: the electrode 622c simultaneously formed with the forming of the gate electrode 622a of the first transistor 641 and the gate electrode 622b of the second transistor 642; the insulating layer 623c simultaneously formed with the forming of the gate insulating layer 623a of the first transistor 641 and the gate insulating layer 623b of the second transistor 642; and the electrode 624c formed simultaneously with the forming of the electrodes 624a, 624b, and the electrodes 625a, 625b, 625c, 625d used as the source electrodes and the drain electrodes of the first transistor 641 and the second transistor 642.
For this reason, the special process for forming the pixel capacitor 643 is not needed, and the capacitor used as the pixel capacitor 643 is formed at the time of performing the process of forming the first transistor 641 and the second transistor 642. In this manner, the drive circuit per pixel which includes the first and second transistors 641 and 642 and the pixel capacitor 643 is formed. It is also possible to form the drive circuit per pixel which includes one transistor and one pixel capacitor according to this embodiment based on the composition that is the same as in the first embodiment. According to this embodiment, it is also possible to form the drive circuit per pixel which includes three or more transistors and one pixel capacitor.
According to this invention, the display device having the multilayer interconnection can be formed without forming any interlayer insulation film, and the productivity can be increased. The process of heating or UV irradiation is performed separately from the process of forming the semiconductor chip, and the display device can be manufactured without adversely affecting the semiconductor chip by the process of heating or UV irradiation. Thereby, it is possible to provide a display device which can be manufactured with good quality and low cost.
The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.
The present application is based on Japanese patent application No. 2008-105993, filed on Apr. 15, 2008, and Japanese patent application No. 2008-138334, filed on May 27, 2008, the contents of which are incorporated herein by reference in their entirety.
Number | Date | Country | Kind |
---|---|---|---|
2008-105993 | Apr 2008 | JP | national |
2008-138334 | May 2008 | JP | national |