JP2010191283A - Method for manufacturing active element substrate, active element substrate, and active type display device - Google Patents

Abstract

An active element substrate manufacturing method capable of suppressing parasitic capacitance without increasing man-hours and exhibiting high aperture ratio and high transmittance is realized.
A transparent insulating layer having a contact hole is formed on a pixel TFT and a signal wiring. The process is photosensitive so as to cover the pixel TFT and the signal wiring. A step of forming the first insulating layer 9 which does not have, a step of forming the second insulating layer 10 having photosensitivity so as to cover the first insulating layer 9, and an exposure of the second insulating layer 10 And a step of patterning by development, and a step of etching the first insulating layer 9 using the second insulating layer 10 as a mask.
[Selection] Figure 1

Description

  The present invention relates to a method of manufacturing an active element substrate in which a pixel electrode is connected to an active element through a contact hole provided in a transparent insulating layer covering an active element such as a thin film transistor (hereinafter referred to as TFT) and a signal wiring. And an active element substrate formed by the manufacturing method and a display device including the same.

  In recent years, liquid crystal display devices, which have been rapidly spread in place of cathode ray tubes (CRT), and active display devices using TFTs typified by organic EL display devices are televisions that take advantage of their energy-saving, thin, and lightweight types. Widely used in monitors, mobile phones, etc.

  Conventionally, in an active display device using these TFTs, a photosensitive interlayer insulating film capable of forming a pattern such as a contact hole by an exposure process and a development process is used as a pixel electrode so that a higher quality display is possible. A configuration provided between the TFT wirings is known.

  FIG. 8 is a diagram showing a schematic configuration of an active matrix substrate 90 provided with the conventional photosensitive interlayer insulating film 92 described above.

  As shown in FIG. 8, the active matrix substrate 90 is provided with a TFT 91 for each pixel, and a photosensitive interlayer insulating film 92 is provided on the TFT 91.

  The photosensitive interlayer insulating film 92 is a positive type photosensitive resist in which an exposed portion is developed, and a contact hole is formed in a region exposed by UV light.

  Although not shown, a transparent pixel electrode made of ITO, IZO, or the like is formed on the photosensitive interlayer insulating film 92, and the pixel electrode is connected to the TFT 91 through the contact hole. Has been.

  According to the above configuration, a pattern such as a contact hole can be formed relatively easily, and the pixel electrode can be provided so as to overlap the wiring, so that the aperture ratio of the display panel can be improved.

  Patent Document 1 describes a method of forming a contact hole by dry etching on an insulating film layer having a multilayer structure composed of an organic film and an inorganic film using a photosensitive resist as a mask.

  Hereinafter, a method for forming the contact hole will be described in detail with reference to FIG.

  As shown in FIG. 9, the data line 119 and the TFT are formed on the transparent substrate 101. The TFT includes a gate electrode 121a, a gate insulating layer 123, and source and drain electrodes 119a and 119b. .

  Further, an organic protective film 129a having a Si bond structure such as benzocyclobutene (BCB) is formed on the TFT, and an inorganic insulating film 129b such as SiNx or SiOx is formed on the organic protective film 129a. Is formed.

  As shown in the drawing, the inorganic film 129b is formed thinner than the organic film 129a, and a photoresist 143 is further coated on the inorganic film 129b. The photoresist 143 is exposed using a mask (not shown) and then developed to form a predetermined pattern.

Thereafter, the substrate 101 is placed in the vacuum chamber 161, and the organic film 129a and the inorganic film 129b are etched by CF ₄ / O ₂ or SF ₆ / O ₂ gas, and at the same time, the photoresist is Ashing is performed by O ₂ gas contained in the gas. At this time, a method for forming a contact hole by adjusting the mixing ratio of CF ₄ or SF ₆ and O ₂ gas and adjusting the etching selectivity of the organic film 129a and the inorganic film 129b is described. ing.

Japanese Patent Laid-Open No. 10-96960 (published on April 14, 1998)

  However, as shown in FIG. 8, in the above-described configuration in which the photosensitive interlayer insulating film 92 is provided between the pixel electrode and the TFT wiring, in order to further reduce the parasitic capacitance that causes problems such as signal delay. In addition, when the photosensitive interlayer insulating film 92 is to be thickened, a contact hole is obtained at a normal film thickness and a normal exposure intensity and time as shown by the dotted line in FIG. There is a problem that it becomes impossible to perform patterning. That is, when the thickness of the photosensitive interlayer insulating film 92 is large, the exposure amount necessary for patterning increases drastically, and the exposure amount in the exposure region of the photosensitive interlayer insulating film 92 becomes insufficient. Sometimes contact holes cannot be formed.

  Further, when the exposure intensity is increased, it becomes difficult to form a fine contact hole. On the other hand, when the exposure is performed at a normal exposure intensity for a long time, there is a problem that the process time becomes long.

  Further, since the photosensitive interlayer insulating film 92 has photosensitivity, it is difficult to impart high transparency to the formed film itself. This reduces the transmittance of the display panel provided.

Further, the method for forming a contact hole described in Patent Document 1 includes a step of forming an organic film 129a and a step of forming an inorganic film 129b on the organic film 129a as shown in FIG. And a step of applying a photoresist 143 on the inorganic film 129b to form a predetermined pattern, and in order to form a contact hole, SF ₆ / O corresponding to the opened portion of the photoresist pattern. ₂ or CF ₄ / O ₂ gas is used to etch the organic film 129a and the inorganic film 129b and simultaneously ash the photoresist 143 using the O ₂ gas. There is a problem that it becomes a factor of cost increase.

  The present invention has been made in view of the above problems, and provides a method for manufacturing an active element substrate that can suppress parasitic capacitance without increasing man-hours and that exhibits high aperture ratio and high transmittance. For the purpose.

  It is another object of the present invention to provide an active element substrate that can suppress parasitic capacitance and exhibit high aperture ratio and high transmittance.

  It is another object of the present invention to provide an active display device having good display quality by including the active element substrate.

  In order to solve the above problems, an active element substrate manufacturing method of the present invention includes an active element, a pixel electrode and a signal wiring connected to the active element, and the pixel electrode includes the active element and the signal. A method of manufacturing an active element substrate connected to the active element through a contact hole provided in a transparent insulating layer covering the wiring, the transparent element having the contact hole on the active element and the signal wiring A step of forming an insulating layer, the step of forming a first insulating layer having an organic material as a main component and having no photosensitivity so as to cover the active element and the signal wiring; and Forming a photosensitive second insulating layer so as to cover the first insulating layer; and exposing and developing the second insulating layer by patterning A step of packaging is characterized by comprising the step of etching the first insulating layer above the second insulating layer as a mask.

  In order to solve the above problems, an active element substrate of the present invention includes an active element, a pixel electrode and a signal wiring connected to the active element, and the pixel electrode includes the active element and the signal wiring. An active element substrate connected to the active element through a contact hole provided in a transparent insulating layer that covers the insulating element, wherein the insulating layer is composed of an organic material as a main component and has no photosensitivity. And a photosensitive second insulating layer formed on the first insulating layer.

  When the insulating layer is made only of a photosensitive resin, there is a problem that the transparency is lowered, and a contact hole cannot be formed with a realistic exposure time at a certain film thickness or more, and the film cannot be thickened. There was a problem. However, according to each of the above structures, the first insulating layer does not have photosensitivity, and therefore does not include a substance that absorbs and reacts with light, and can be a film with high transmittance. .

  In addition, the first insulating layer can be thickened by using an organic material as a main component, and the first insulating layer has photosensitivity because the insulating layer has the above-described stacked structure. Even if not, the contact hole can be easily formed in a short time by etching using the second insulating layer as a mask. For this reason, the first insulating layer can be thickened relatively freely. Therefore, according to the above configuration, the parasitic capacitance can be significantly reduced, and even if the insulating layer is thickened, a decrease in transmittance can be suppressed.

Further, since the second insulating layer has photosensitivity, it is not necessary to form a photoresist separately from the first and second insulating layers in order to form the contact hole. The second insulating layer can be patterned and used as it is as a mask in the dry etching process. According to the present invention, since the first insulating layer contains the organic material as described above, the selectivity with respect to etching such as O ₂ gas ashing can be improved.

  Furthermore, since the first insulating layer to be thickened is mainly composed of an organic material, flexibility can be imparted to the first insulating layer that is a thick film, and generation of cracks and the like is suppressed. can do.

  Further, since the insulating layer has a laminated structure of the first insulating layer and the second insulating layer, it is easy to increase the thickness. Therefore, parasitic capacitance can be further suppressed.

  As described above, according to the above configuration, it is possible to obtain an active element substrate that can suppress parasitic capacitance and increase the aperture ratio and transmittance without increasing man-hours.

  In the method for manufacturing an active element substrate of the present invention, it is preferable to form a layer made of a photosensitive siloxane resin as the second insulating layer.

  In the active element substrate of the present invention, the second insulating layer is preferably a layer made of a photosensitive siloxane resin.

  According to the above configuration, since the photosensitive insulating siloxane resin showing high transmittance, high etching resistance, high flatness, and high hardness is used as the second insulating layer, the selectivity in etching can be increased. In addition, an active element substrate manufacturing method having high transmittance, high flatness, and process resistance to subsequent processes can be realized.

  The method for manufacturing an active element substrate according to the present invention is such that the second insulating layer is completely removed when a contact hole is formed in the first insulating layer using the second insulating layer as a mask. It is preferable that the film thickness of the second insulating layer and the etching selectivity between the second insulating layer and the first insulating layer are set.

  According to the above configuration, when it is necessary to remove the second insulating layer, it is not necessary to separately add a second insulating layer removing step in subsequent steps.

  The method of manufacturing an active element substrate of the present invention includes a step of forming an inorganic protective film between the active element and the first insulating layer, and using the first insulating layer and the second insulating layer as a mask. It is preferable to further include a step of etching the inorganic protective film.

  According to the said structure, the said active element can be protected from an ionic impurity, a water | moisture content, etc. by providing an inorganic protective film on the said active element further. Therefore, it is possible to realize a method for manufacturing an active element substrate with further improved reliability.

  The method for manufacturing an active element substrate according to the present invention is such that the second insulating layer is completely removed when contact holes are formed in the inorganic protective film using the first insulating layer as a mask. It is preferable that the thickness of the second insulating layer and the etching selectivity between the second insulating layer and the inorganic protective film are set.

  According to the above configuration, when it is necessary to remove the second insulating layer, it is not necessary to separately add a second insulating layer removing step in subsequent steps.

  In the method for manufacturing an active element substrate of the present invention, the first insulating layer is a color filter layer, and the color filter layer is preferably formed by a printing method or an inkjet method.

  Conventionally, color filters and holes are formed using a photosensitive colored resist. In such a case, it is necessary to apply, expose, and develop the photosensitive colored resist for each color. As a result, the cost was increased and the yield was reduced.

  On the other hand, according to the above configuration, the color filter layer that is the first insulating layer is formed by, for example, printing or ink-jetting a plurality of first insulating layer materials that contain pigments of each color and that do not have photosensitivity. Accordingly, the amount of the first insulating layer material used can be significantly reduced, the manufacturing process can be shortened, and the cost increase and the yield reduction can be suppressed.

  In addition, since the first insulating layer material does not need to have photosensitivity, a material having a wide selection range and capable of improving color purity can be used.

  In the active element substrate of the present invention, the first insulating layer is preferably a color filter layer as described above.

  According to the above configuration, there is no need to separately provide a color filter layer on the color filter substrate side as in the prior art. That is, the first insulating layer also serves as a conventional color filter layer.

  Therefore, according to the above configuration, when the color filter substrate and the active element substrate are bonded together as in the prior art, it is not necessary to perform highly accurate alignment adjustment.

  In addition, since the first insulating layer material does not need to have photosensitivity, a material having a wide selection range and capable of improving color purity can be used.

  In the active element substrate of the present invention, it is preferable that the first insulating layer has a thickness of 0.5 to 20 μm.

  According to the above configuration, since the first insulating layer is provided with a thickness of 0.5 to 20 μm, it is possible to suppress parasitic capacitance that causes problems such as signal delay.

  In order to solve the above-described problems, an active display device according to the present invention includes the active element substrate.

  According to the above configuration, an active display device with good display quality can be realized by providing the active element substrate.

  As described above, the manufacturing method of the active element substrate of the present invention includes the step of forming the transparent insulating layer having the contact hole on the active element and the signal wiring, which includes the active element and the signal. Forming a first non-photosensitive insulating layer mainly composed of an organic material so as to cover the wiring; and a photosensitive second insulating so as to cover the first insulating layer. The method includes a step of forming a layer, a step of patterning the second insulating layer by exposure and development, and a step of etching the first insulating layer using the second insulating layer as a mask.

  Therefore, it is possible to suppress the parasitic capacitance without increasing the number of man-hours, and to realize an active element substrate manufacturing method that exhibits a high aperture ratio and a high transmittance.

  In the active element substrate of the present invention, the insulating layer includes a first insulating layer containing an organic material as a main component and having no photosensitivity, and a photosensitivity formed on the first insulating layer. The first insulating layer is formed of an organic insulating layer.

  As a result, the parasitic capacitance can be suppressed, and an active element substrate having a high aperture ratio and a high transmittance can be realized.

  The active display device of the present invention includes the active element substrate.

  Therefore, there is an effect that an active display device having a good display quality can be realized.

It is a figure which shows the cross-section of the active element substrate of one embodiment of this invention. It is a top view which shows schematic structure of one pixel area | region of the active element substrate of one embodiment of this invention. It is a process figure for demonstrating the manufacturing process of the active element substrate of one embodiment of this invention. It is sectional drawing which shows schematic structure of the liquid crystal display device provided with the active element substrate of one embodiment of this invention. It is a figure which shows the structure of a part of active element substrate of other embodiment of this invention. It is a figure which shows the structure of the active element substrate of other embodiment of this invention. It is sectional drawing which shows schematic structure of the liquid crystal display device provided with the active element substrate of other embodiment of this invention. It is a figure which shows schematic structure of the active matrix substrate provided with the conventional photosensitive interlayer insulation film. In the prior art, it is a figure for demonstrating the method of forming a contact hole in the insulating film layer of a multilayered structure.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are merely one embodiment, and the scope of the present invention should not be construed as being limited thereto.

  An active element substrate according to an embodiment of the present invention is an active element substrate that can suppress parasitic capacitance and exhibits high aperture ratio and high transmittance.

  In addition, an active display device according to an embodiment of the present invention is an active display device in which the display quality is further improved by including the active element substrate.

  In addition, the method for manufacturing an active element substrate according to an embodiment of the present invention is a method for manufacturing an active element substrate that can suppress parasitic capacitance without increasing man-hours and that exhibits high aperture ratio and high transmittance. .

[Embodiment 1]
Hereinafter, based on FIGS. 1-2, the structure of the active element board | substrate 1 of one embodiment of this invention is demonstrated.

  In the present embodiment, the active element substrate 1 will be described by taking a TFT substrate (active matrix substrate) including a TFT as an active element as an example. In the present embodiment, a liquid crystal display device will be described as an example of a display device including the active element substrate 1.

  However, the present invention is not limited to this, and various conventionally known active elements can be used. The display device is not limited to a liquid crystal display device, and various known display media can be used in place of the liquid crystal.

  FIG. 1 is a cross-sectional view taken along the line A-A ′ of FIG. 2 and shows a cross-sectional structure of the active element substrate 1 according to the embodiment of the present invention. FIG. 2 is a plan view showing a schematic configuration of one pixel region of the active element substrate 1 according to the embodiment of the present invention. 1 corresponds to a cross-sectional view taken along the line A-A ′ of FIG. 2.

  The active element substrate 1 has a display area composed of a large number of pixel areas arranged in a matrix. In each of the pixel regions, as shown in FIG. 2, a pixel TFT 7 is formed as an active element for controlling the pixel electrode 11, and a data line 6 for supplying an image signal is a source of the pixel TFT 7. It is electrically connected to the electrode 6a.

  The pixel electrode 11 and the pixel TFT 7 are provided in a matrix so as to correspond to the intersection of the gate bus line 3 and the data line 6.

  Further, the gate bus line 3 is electrically connected to the gate electrode 3a of the pixel TFT 7 shown in FIG. 1, and pulse scanning signals are sequentially applied to the gate bus line 3 at a predetermined timing. It is configured as follows.

  Further, as shown in FIGS. 1 and 2, the pixel electrode 11 is electrically connected to the drain electrode 6b of the pixel TFT 7, and the pixel TFT 7 which is an active element is switched on. During the period, the image signal voltage supplied from the data line 6 is applied to the pixel electrode 11.

  The voltage applied as described above is applied to the liquid crystal layer sandwiched between the pixel electrode 11 and a counter electrode (not shown), and is held for a certain period when the pixel TFT 7 is switched off. .

  Here, in order to prevent the image signal to be held from leaking and causing a display defect such as flicker, a capacitance formed between the pixel electrode 11 (between the pixel electrode 11 and the counter electrode). It is necessary to provide an auxiliary capacitor in parallel with the liquid crystal capacitor formed.

  In other words, by providing the auxiliary capacitor as described above, the auxiliary capacitor can stably hold the image signal for a longer period of time, and a liquid crystal display device with improved display quality can be obtained. Can do.

  In the present embodiment, in order to secure the auxiliary capacitance, as shown in FIG. 2, the auxiliary capacitance wiring 12 extends across the central portion of the pixel electrode 11 in parallel with the gate bus line 3. Is provided.

  In the active element substrate 1 of the present embodiment, a gate insulating layer 4 that is provided thinner than a first insulating layer 9 to be described later in detail is provided on the auxiliary capacitance wiring 12. It is preferable that the auxiliary capacitance electrode 13 is provided on the layer 4 so as to face the auxiliary capacitance wiring 12.

  According to the above configuration, since the first insulating layer 9 described later in detail is a thick film, a sufficient auxiliary capacitance is ensured by the configuration of the auxiliary capacitor wiring 12 / first insulating layer 9 / pixel electrode 11. Even if this is difficult, the auxiliary capacitance is formed by the configuration of the auxiliary capacitance wiring 12 / the gate insulating layer 4 provided thinner than the first insulating layer 9 / the auxiliary capacitance electrode 13 connected to the drain electrode 6b of the pixel TFT 7. Can be secured.

  Therefore, according to the above configuration, it is possible to realize the active element substrate 1 that can secure a sufficient auxiliary capacitance even when the first insulating layer 9 is a thick film.

  Hereinafter, the configuration of the active element substrate 1 according to the embodiment of the present invention will be described in more detail based on FIG. 1 and FIG.

  As already described above, the active element substrate 1 has a plurality of pixels, and each pixel is provided with a pixel TFT 7 and a pixel electrode 11.

  As shown in FIGS. 1 and 2, transparent insulating layers 9 and 10 are provided between the pixel electrode 11 and the pixel TFT 7 and the wirings 3 and 6 connected to the pixel TFT 7. Is provided.

  The transparent insulating layers 9 and 10 cover the first insulating layer 9 having no photosensitivity provided so as to cover the pixel TFT 7 and the wirings 3 and 6, and the first insulating layer 9. And a second insulating layer 10 having photosensitivity provided.

  Further, the first insulating layer 9 is provided with a thickness of 0.5 to 20 μm, and the second insulating layer 10 has higher etching resistance than the first insulating layer 9. In the first insulating layer 9 and the second insulating layer 10, contact holes 9a and 10a for connecting the pixel electrode 11 and the pixel TFT 7 are formed.

  According to the above configuration, since the first insulating layer 9 does not have photosensitivity, the first insulating layer 9 does not include a substance that absorbs and reacts with light, and can be a film with high transmittance.

  Further, since the first insulating layer 9 has no photosensitivity, the first insulating layer 9 is not configured to be patterned by exposure. Therefore, the first insulating layer 9 can be thickened relatively freely, and causes parasitic capacitance that causes problems such as signal delay. Can be significantly reduced, and even if the film thickness is increased, a decrease in transmittance can be suppressed.

  Further, the second insulating layer 10 formed on the first insulating layer 9 has photosensitivity and has higher etching resistance than the first insulating layer 9, so that the first insulating layer 9 In order to form the contact hole 9a, it is not necessary to use a separate photoresist, and the second insulating layer 10 can be patterned and used as it is as a mask in the etching process.

  In the active element substrate 1, the insulating layer has a two-layer structure of the first insulating layer 9 and the second insulating layer 10, and the insulating layers 9 and 10 are stacked. The parasitic capacitance can be further suppressed.

  As described above, according to the above-described configuration, it is possible to realize the active element substrate 1 that can suppress the parasitic capacitance and exhibit high aperture ratio and high transmittance.

  Note that the first insulating layer 9 and / or the second insulating layer 10 provided in the active element substrate 1 may be porous.

  Since the porous insulating layer contains a large amount of air having a dielectric constant of 1, the dielectric constant of the porous insulating layer itself can be lowered, and the parasitic capacitance can be further reduced.

  Therefore, the active element substrate 1 that can further suppress the parasitic capacitance can be realized.

  In the present embodiment, the first insulating layer 9 includes an epoxy group-containing polymerizable unsaturated compound, a polymerizable unsaturated carboxylic acid and / or a polymerizable unsaturated polyvalent carboxylic acid, which is a conventional thermosetting resin. Although what consists of copolymers, such as an anhydride, was used, if it has an organic material (organic substance) as a main component, it will not be limited to this.

  The first insulating layer 9 is preferably thicker and contains 20% by weight or more, more preferably 60% by weight or more, from the viewpoint of selectivity in the dry etching process. More preferably, it is formed only of organic substances.

  Since the first insulating layer 9 contains an organic substance as described above, it is possible to increase the thickness as described above, and to give flexibility to the first insulating layer 9. Generation of cracks and the like can be suppressed.

Further, since the first insulating layer 9 contains an organic substance, the selection ratio with respect to O ₂ gas ashing can be improved.

  In order to adjust the dielectric constant, for example, a thermosetting resin composition containing a cage silsesquioxane derivative may be used.

In this embodiment, as an etching method, but using the dry etching method according to O ₂ gas, considering the etching selection ratio, it is possible to use wet etching. Moreover, since a conventionally well-known method can be used about the dry etching method, the description is abbreviate | omitted.

  Therefore, when the dry etching selectivity in the step of forming the first insulating layer 9 is taken into consideration, the inorganic content contained for adjusting the dielectric constant is small in the thermosetting resin composition. It is preferable.

  In the present embodiment, the second insulating layer 10 is made of a transparent insulating material having photosensitivity and is used as a mask when the contact hole 9a is formed in the first insulating layer 9. There is no particular limitation as long as it can be used.

  As the second insulating layer 10, for example, forming a layer made of a photosensitive siloxane resin (siloxane-based polymer) has a high transmittance, a high dry etching resistance, and a viewpoint of an etching selectivity. Desirable from.

  In the present embodiment, the second insulating layer 10 is a negative photocuring containing a siloxane derivative obtained by hydrolysis / condensation of alkoxysilane and a photoacid generator for imparting photosensitivity. Although the siloxane resin layer made of the conductive resin composition is formed, the present invention is not limited to this.

  As described above, in the active element substrate 1, the first insulating layer 9 is preferably an organic insulating layer.

Since the first insulating layer 9 is an organic insulating layer, the selectivity with respect to O ₂ gas ashing can be improved, and the first insulating layer 9 which is a thick film is given flexibility. And the occurrence of cracks and the like can be suppressed.

  In the active element substrate 1, the second insulating layer 10 is preferably a siloxane resin.

  According to the above configuration, since the second insulating layer 10 is a siloxane resin exhibiting high transmittance, high dry etching resistance, high flatness, and high hardness, the selectivity in dry etching is high and the high transmittance is high. Thus, the active element substrate 1 having high flatness and process resistance to subsequent processes can be realized.

  In the present embodiment, a negative photocurable resin composition is used as the second insulating layer 10, but a positive photocurable resin composition may be used.

  Further, as shown in FIG. 1, in the active element substrate 1, between the pixel TFT 7 and the first insulating layer 9 provided so as to cover the pixel TFT 7, An inorganic protective film 8 is preferably provided.

  According to the above configuration, the pixel TFT 7 can be protected from ionic impurities, moisture, and the like by further providing the inorganic protective film 8 on the pixel TFT 7. Therefore, the active element substrate 1 with further improved reliability can be realized.

  In the present embodiment, a silicon nitride film having a dense structure formed by a sputtering method, a plasma CVD method, or the like is used as the inorganic protective film 8, but a silicon oxide film, a silicon oxynitride film, or the like is used. Alternatively, a film formed by stacking the above films may be used.

  In the case where a porous film is used as the first insulating layer 9 and / or the second insulating layer 10 in consideration of a dielectric constant, the inorganic protective film 8 is preferably provided. .

  Hereinafter, a schematic manufacturing process of the active element substrate 1 will be described with reference to FIG.

<Manufacturing process of active element substrate 1>
FIG. 3 is a process diagram for explaining a manufacturing process of the active element substrate 1 according to the embodiment of the present invention.

  As a method of forming the pixel TFT 7 on the substrate 2, which is a process before applying the first insulating layer 9, a conventionally known method can be used, and the description thereof is omitted.

  In the present embodiment, glass is used as the substrate 2, but the present invention is not limited to this, and as the substrate 2, quartz, plastic, silicon wafer, metal, ceramic, etc. are used in addition to the glass. be able to.

  The semiconductor channel layer 5 in the pixel TFT 7 is not limited to amorphous silicon, but is polycrystalline silicon, amorphous germanium, polycrystalline germanium, amorphous silicon / germanium, polycrystalline silicon / germanium, amorphous. Silicon carbide, polycrystalline silicon carbide, or the like can be used. These oxides and organic semiconductor layers can also be used.

  As shown in FIG. 3A, the first insulating layer 9 is formed on the substrate 2 on which the pixel TFT 7 is formed.

  The first insulating layer 9 is formed by applying the thermosetting resin composition already described above and performing a predetermined heat treatment.

  Subsequently, as shown in FIG. 3B, a photosensitive second insulating layer 10 is formed on the first insulating layer 9.

  The second insulating layer 10 is a mask on which a predetermined pattern (not shown) is formed after applying the above-described negative-type photocurable resin composition, prebaking (drying under reduced pressure) at a predetermined temperature. The contact hole 10a was formed by exposing the film using an alkali developer and developing using an alkali developer, and then post-baking at a predetermined temperature.

Subsequently, as shown in FIG. 3C, by using the pattern formed in the second insulating layer 10 as a mask, the lower first insulating layer 9 is O ₂ gas ashed. Then, a contact hole 9 a is formed in the first insulating layer 9.

  Next, as shown in FIG. 3D, the inorganic protective film 8 is dry-etched using the patterned first insulating layer 9 and second insulating layer 10 as a mask, Contact holes 8 a are also formed in the inorganic protective film 8.

  In addition, when forming a hole in the location where the gate insulating layer 4 and the inorganic protective film 8 are stacked without sandwiching the drain electrode 6b, the gate insulating layer 4 and the inorganic protective film 8 are formed. By etching in one step, a contact hole can be formed. In addition, the second insulating layer 10 can be provided sufficiently thicker than the total thickness of the gate insulating layer 4 and the inorganic protective film 8. In such a case, the gate insulating layer 4 and the inorganic insulating layer 10 can be provided. Even after the contact hole is formed in the protective film 8, the second insulating layer 10 can be left.

  Thereafter, although not shown, a transparent conductive film such as ITO or IZO is formed on the entire surface by sputtering or the like, a desired pattern is formed using a photoresist, and the transparent conductive film is formed using the resist pattern as a mask. The pixel electrode 11 is formed by patterning by etching. The pixel electrode 11 is connected to the drain electrode 6b of the pixel TFT 7 through contact holes 8a, 9a, and 10a.

  As described above, the manufacturing method of the active element substrate 1 includes the step of forming the first insulating layer 9 having no photosensitivity so as to cover the pixel TFT 7 and the wirings 3 and 6, and the first A step of forming a photosensitive second insulating layer 10 so as to cover the insulating layer 9, a step of patterning the second insulating layer 10 by exposure and development, and a step of forming the second insulating layer 10 Etching the first insulating layer 9 as a mask.

  Therefore, since the contact hole 9a is formed by dry etching using the second insulating layer 10 as a mask, the first insulating layer 9 does not include a substance that absorbs and reacts with light, and is a film having high transmittance. be able to.

  Furthermore, since the first insulating layer 9 is not configured to be patterned by exposure as described above, the first insulating layer 9 can be thickened relatively freely, and the parasitic capacitance can be greatly reduced. Even if the film is thickened, a decrease in transmittance can be suppressed.

  On the other hand, the second insulating layer 10 formed on the first insulating layer 9 can form a contact hole 10a by exposure and development, and is more resistant to dry etching than the first insulating layer 9. Since the contact hole 9a can be formed in the first insulating layer 9, it is not necessary to use a separate photoresist, and the second insulating layer 10 is patterned and left in a dry etching process. Can be used as a mask.

  Furthermore, in the manufacturing method of the active element substrate 1, the insulating layer has a two-layer structure of the first insulating layer 9 and the second insulating layer 10, and the insulating layers 9 and 10 are laminated. Therefore, the parasitic capacitance can be further suppressed.

  As described above, according to the above configuration, it is possible to realize a method of manufacturing the active element substrate 1 that can suppress parasitic capacitance and increase the aperture ratio and the transmittance without increasing the number of steps.

  Then, the active element substrate 1a of the present embodiment can have a configuration as shown in FIG.

  By adjusting the film thickness and the dry etching selection ratio between the second insulating layer 10 and the inorganic protective film 8, the contact hole 8a is formed in the inorganic protective film 8 as shown in FIG. When the formation is completed, the second insulating layer 10 can be prevented from remaining.

  Further, the second insulating layer 10 is not left when the formation of a hole is completed at a position where the gate insulating layer 4 and the inorganic protective film 8 are stacked without sandwiching the drain electrode 6b. You can also.

  Hereinafter, a specific example for realizing the above configuration will be described. For example, when the dry etching rate is 1: 1, the thickness of the second insulating layer 10 is that of the inorganic protective film 8 and the gate insulating layer 4. It is desirable that it is equal to or less than the total film thickness.

  When the dry etching rate of the inorganic protective film 8 and the gate insulating layer 4 and the second insulating layer 10 is 1: X, the film thickness of the second insulating layer 10 is the same as that of the inorganic protective film 8. It may be equal to or less than that obtained by multiplying the total thickness of the gate insulating layer 4 by X.

  Therefore, according to the above configuration, when it is necessary to remove the second insulating layer 10, it is not necessary to separately add a step of removing the second insulating layer 10 in the subsequent steps.

  In addition, about the dry etching methods, such as the said inorganic protective film 8 and the said 2nd insulating layer 10, since a conventionally well-known method can be used, the description is abbreviate | omitted.

  Finally, as shown in FIG. 3F, a transparent conductive material such as ITO or IZO is formed on the first insulating layer 9 remaining after the second insulating layer 10 is completely dry etched. A film was formed on the entire surface by sputtering or the like, a desired pattern was formed using a photoresist, and the transparent conductive film was etched using the resist pattern as a mask to perform patterning to form a pixel electrode 11. . The pixel electrode 11 is connected to the drain electrode 6b of the pixel TFT 7 through contact holes 8a and 9a.

  FIG. 3F shows a schematic configuration of the active element substrate 1a.

  Next, a liquid crystal display device 40 including the active element substrate 1 will be described with reference to FIG. For convenience of explanation, explanation of members already described in the description of the active element substrate 1 is omitted.

  FIG. 4 is a cross-sectional view showing a schematic configuration of the liquid crystal display device 40 of the present embodiment.

  As shown in FIG. 4, the liquid crystal display device 40 includes the active element substrate 1 and a color filter substrate 30 having a common electrode 16 facing the active element substrate 1, and the liquid crystal 17 is sealed between the substrates by a sealing material. A liquid crystal display panel having the above structure is provided.

  Further, the active element substrate 1 and the color filter substrate 30 are provided with deflection plates 18a and 18b.

  Further, as shown in FIG. 4, on the substrate 14 of the color filter substrate 30, colored portions having respective colors of red (R), green (G), and blue (B), and a black matrix The color filter layer 15 comprised from these is provided.

  In addition, a backlight 20 is disposed on the back surface of the liquid crystal display panel (on the active element substrate 1 side), and the backlight 20 emits light toward the liquid crystal display panel.

  Furthermore, an optical sheet 19 can be provided on the light exit surface side of the backlight 20. The optical sheet 19 includes, for example, a diffusion plate and a composite function optical sheet, and the composite function optical sheet includes a plurality of optical elements selected from various optical functions including diffusion, refraction, condensing, and polarization. Functional.

  The optical sheet 19 is preferably used in combination as appropriate depending on the price and performance of the liquid crystal display device.

  As described above, the liquid crystal display device 40 of this embodiment includes the active element substrate 1.

  Therefore, the liquid crystal display device 40 with good display quality can be realized.

[Embodiment 2]
Next, a second embodiment of the present invention will be described based on FIGS. This embodiment shows a modification in the case where the first insulating layer 9 in Embodiment 1 is a color filter layer. In the step of forming the color filter layer, a printing method or an inkjet method is used. It is used.

  Other configurations and manufacturing processes are as described in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and descriptions thereof are omitted.

  FIG. 5 is a diagram showing a configuration of a part of an active element substrate 1b according to another embodiment of the present invention.

  As shown in the drawing, a color filter layer is formed as a first insulating layer 9b on the substrate 2 on which the pixel TFT 7 is formed.

  The first insulating layer 9b is, for example, a red (R), green (G), or blue (B) colored resist used when forming a conventional color filter layer on the thermosetting resin composition already described above. The pigment dispersion liquid of each color contained in is contained.

  In the present embodiment, as shown in the drawing, the first insulating layer 9b is exposed and developed using a photosensitive black colored resist to form a black matrix 21 having a predetermined pattern. Thereafter, a portion surrounded by the black matrix 21 (a portion where the black matrix 21 does not exist) is subjected to a thermosetting resin composition containing the pigment dispersion liquid of each color using an inkjet method. And formed by performing a predetermined heat treatment.

  In this embodiment, the ink jet method is used as described above, but the present invention is not limited to this, and it is needless to say that a printing method or the like can be used.

  According to the above configuration, there is no need to separately provide a color filter layer on the color filter substrate side as in the prior art. That is, the first insulating layer 9b also serves as a conventional color filter layer.

  Conventionally, a color filter and a contact hole are formed using a photosensitive colored resist. In such a case, it is necessary to apply, expose, and develop the photosensitive colored resist for each color. It was long, leading to an increase in cost and a decrease in yield.

  On the other hand, according to the said structure, the usage-amount of the said thermosetting composition by forming the several thermosetting composition which has the pigment of each color which does not have photosensitivity using a printing method or an inkjet method. Can be significantly suppressed, the manufacturing process can be shortened, and the increase in cost and the decrease in yield can be suppressed.

  Further, unlike the prior art, when the color filter substrate and the active element substrate are bonded together, it is not necessary to perform highly accurate alignment adjustment.

  In addition, since the thermosetting composition for forming the first insulating layer 9b does not need to have photosensitivity, a material having a wide selection range of materials and capable of further improving color purity is used. it can.

  FIG. 6 is a diagram showing a configuration of an active element substrate 1b according to another embodiment of the present invention.

  As shown in the drawing, a second insulating layer 10 is formed on the first insulating layer 9b formed by the ink jet method.

  The second insulating layer 10 planarizes a step generated between the black matrix 21 and the first insulating layer 9b and functions as an overcoat, so that the active element has good process resistance to a subsequent process. The substrate 1b can be realized.

  FIG. 7 is a cross-sectional view showing a schematic configuration of a liquid crystal display device 40a including an active element substrate 1b according to another embodiment of the present invention.

  As shown in the drawing, the active element substrate 1b was formed by subjecting a thermosetting resin composition containing the pigment dispersion liquid of each color to a target and performing a predetermined heat treatment by an inkjet method. Since the first insulating layer 9b is provided, there is no color filter layer on the color filter substrate 30a side.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and the present invention can be obtained by appropriately combining technical means disclosed in different embodiments. Embodiments are also included in the technical scope of the present invention.

  The present invention can be applied to a liquid crystal display device and an active display device using an active element typified by an organic EL display device.

1, 1a, 1b Active element substrate 2, 14 Substrate 3 Gate bus line (signal wiring)
3a Gate electrode 4 Gate insulating layer 6 Data line (signal wiring)
6a Source electrode 6b Drain electrode 7 Pixel TFT (active element)
DESCRIPTION OF SYMBOLS 8 Inorganic protective film 9, 9b 1st insulating layer 10 2nd insulating layer 8a, 9a, 10a Contact hole 11 Pixel electrode 12 Auxiliary capacity wiring 13 Auxiliary capacity electrode 30 Color filter substrate 40, 40a Liquid crystal display device (active type display) apparatus)

Claims (11)

An active element, and a pixel electrode and a signal wiring connected to the active element. The pixel electrode is connected to the active element through a contact hole provided in a transparent insulating layer covering the active element and the signal wiring. A method for manufacturing a connected active element substrate, comprising:
Forming a transparent insulating layer having the contact hole on the active element and the signal wiring, the process comprising:
Forming a first insulating layer mainly composed of an organic material and not photosensitive so as to cover the active element and the signal wiring;
Forming a photosensitive second insulating layer so as to cover the first insulating layer;
Patterning the second insulating layer by exposure and development;
And a step of etching the first insulating layer using the second insulating layer as a mask.   2. The method of manufacturing an active element substrate according to claim 1, wherein a layer made of a siloxane resin is formed as the second insulating layer.   The thickness of the second insulating layer and the thickness of the second insulating layer are such that the second insulating layer is completely removed at the time when the contact hole using the second insulating layer as a mask is formed in the first insulating layer. 3. The method of manufacturing an active element substrate according to claim 1, wherein an etching selection ratio between the second insulating layer and the first insulating layer is set. 4. Forming an inorganic protective film between the active element and the first insulating layer;
3. The method of manufacturing an active element substrate according to claim 1, further comprising: etching the inorganic protective film using the first insulating layer and the second insulating layer as a mask.   The thickness of the second insulating layer and the second thickness are such that all of the second insulating layer is removed when contact holes using the first insulating layer as a mask are formed in the inorganic protective film. The method of manufacturing an active element substrate according to claim 4, wherein an etching selection ratio between the insulating layer and the inorganic protective film is set. The first insulating layer is a color filter layer,
The method for manufacturing an active element substrate according to claim 1, wherein the color filter layer is formed by a printing method or an inkjet method. An active element, a pixel electrode connected to the active element, and a signal wiring;
The pixel electrode is an active element substrate connected to the active element through a contact hole provided in a transparent insulating layer covering the active element and the signal wiring,
The insulating layer includes a first insulating layer having an organic material as a main component and having no photosensitivity, and a photosensitive second insulating layer formed on the first insulating layer. An active element substrate characterized by comprising:   8. The active element substrate according to claim 7, wherein the second insulating layer is a layer made of a photosensitive siloxane resin.   9. The active element substrate according to claim 7, wherein the first insulating layer is a color filter layer.   The active element substrate according to claim 7, wherein the first insulating layer has a thickness of 0.5 to 20 μm.   An active display device comprising the active element substrate according to claim 7.

Images