WO2006109586A1

WO2006109586A1 - Substrate with conductive layer, display unit and process for producing substrate with conductive layer

Info

Publication number: WO2006109586A1
Application number: PCT/JP2006/306752
Authority: WO
Inventors: Toshihide Tsubata
Original assignee: Sharp Kabushiki Kaisha
Priority date: 2005-04-06
Filing date: 2006-03-30
Publication date: 2006-10-19

Abstract

A substrate furnished with a conductive layer in which even in the use of resource-rich zinc oxide, the zinc oxide is resistant to corrosion; a relevant display unit; and a process for producing such a substrate with conductive layer. There is provided a substrate with conductive layer (active matrix substrate (30), color filter substrate (33)), characterized in that it has a laminate structure (picture electrode (3), transparent electrode (37)) having, superimposed on a substrate, multiple conductive layers including at least a first conductive layer (ZnO layer (3b), ZnO layer (37b)) composed mainly of zinc oxide, and that the material of second conductive layer (ITO layer (3a), ITO layer (37a)) of the laminate structure positioned on the surface brought into contact with washing liquid at the washing step exhibits a corrosion resistance to washing liquid higher than that of zinc oxide.

Description

TECHNICAL FIELD The present invention relates to a substrate having a conductive layer, a display device, and a method for manufacturing a substrate having a conductive layer.

The present invention relates to a substrate provided with a conductive layer that can be used for a display substrate such as an active matrix substrate or a color filter substrate, a display device, and a method for manufacturing a substrate provided with a conductive layer.

Background art

[0002] Currently, liquid crystal display devices have features such as small size, thinness, low power consumption, and light weight, and are widely used in various electronic devices. In particular, an active matrix type liquid crystal display device having a switching element as an active element can provide display characteristics equivalent to those of a CRT (Cathode Ray Tube). Therefore, OA equipment such as a personal computer, AV equipment such as a television, and a portable device. Widely applied to telephones. In recent years, liquid crystal display devices have been rapidly improved in quality, such as upsizing, higher definition, and improved pixel effective area ratio (higher aperture ratio). A liquid crystal panel of a liquid crystal display device typically has a structure in which an active matrix substrate and a color filter substrate are bonded to face the active matrix substrate, and liquid crystal is injected between the substrate and the substrate. Manufactured. Then, a liquid crystal display device is manufactured by connecting a driver or the like to the external lead terminal of the liquid crystal panel.

[0003] An active matrix substrate, which is a component of a liquid crystal display device that achieves the above-described object, has signal lines and scanning lines provided on an insulating substrate, and the signal lines and scanning lines cross each other. A switching element and a pixel electrode provided at the intersection are provided.

[0004] Further, as described above, a color filter substrate is bonded so as to face the active matrix substrate, and liquid crystal is injected between the substrates to manufacture a liquid crystal display device. As the color filter substrate mentioned here, for example, the color regions of R (red), G (green), and B (blue) are created so as to coincide with the pixel region on the active matrix substrate side. Other than the above, a substrate in which a black matrix (light-shielding film) is filled and a transparent electrode is formed on the black matrix can be cited.

[0005] In addition, in recent years, the performance of liquid crystal display devices used particularly for large-sized TVs has been improved. Therefore, there is a strong demand for improvement in response speed and viewing angle characteristics (wide viewing angle technology). An MVA (Multi-Domain Vertical Alignment) type liquid crystal display device, which is a vertical alignment type liquid crystal display device that applies a technology that satisfies these requirements, has been proposed (for example, see Patent Document 1).

[0006] The active matrix substrate surface or color filter substrate of this MVA type liquid crystal display device has protrusions (protrusions for alignment control) for controlling the pretilt of liquid crystal molecules in order to bring out the above-mentioned performance. There is a slit! /

FIG. 7 is a plan view showing one pixel in the active matrix substrate 130 of the MVA type display device and a part of the pixels located adjacent to the one pixel. Note that the active matrix substrate 130 shown in FIG. 7 has a configuration including a thin film transistor array. As shown in FIG. 7, in one pixel of the active matrix substrate 130, a gate line (scanning line) 101 and a source line (signal line) 102 are arranged so as to cross each other. A switching element (thin film transistor, hereinafter referred to as TFT) 114 and a pixel electrode 103 are arranged at the intersecting portion. The switching element 114 is formed with a gate electrode 104 connected to the gate line 101, a source electrode 105 connected to the source line 102, a drain electrode 106a connected to the pixel electrode 103, and an island-shaped semiconductor layer 125. The

[0008] A drain lead electrode 106b is connected to the pixel electrode 103 via a contact hole 109. Further, the drain extraction electrode 106b forms an auxiliary capacitance by facing the auxiliary capacitance line 107 with the gate insulating film 111 interposed therebetween.

Next, a method for manufacturing a thin film transistor array will be briefly described with reference to FIGS. 7 and 8, taking the active matrix substrate 130 as an example. FIG. 8 is a cross-sectional view taken along line CI-C2 of the thin film transistor array shown in FIG.

[0010] First, a gate line (scanning line) 101, a gate electrode 104, and an auxiliary capacitance line 107 are formed on a substrate 110 having a transparent insulating substrate force such as glass by film formation, photolithography, and etching. Form at the same time.

[0011] Next, a gate insulating film 111, an active semiconductor layer 112, a low-resistance semiconductor layer (eg, n-type amorphous silicon) 113 are formed thereon, and an island-shaped semiconductor layer 125 is photolithographically formed. And formed by etching. [0012] Further, the source line 102, the source electrode 105, the drain electrode 106a, and the drain extraction electrode 106b are simultaneously formed by film formation, photolithography, and etching, and the n-type semiconductor layer 113 is continuously formed as the source Perform drain isolation etching.

[0013] Thereafter, a lower interlayer insulating film 120 having a force such as SiNx (silicon nitride film) is formed so as to cover the entire surface. Subsequently, an upper organic interlayer insulating film 115 such as a photosensitive acrylic resin is formed, and a contact hole pattern is formed by photolithography at a position where a contact hole 109 is to be formed later.

Next, in order to form the contact hole 109, the gate line external lead terminal, and the source line external lead terminal, the lower interlayer insulating film 120 and the gate insulating film 111 are continuously formed using the upper organic interlayer insulating film 115 as a mask. And etch.

Next, a transparent conductive film such as ITO (Indium Tin Oxide) is formed so as to cover the contact hole 109, the gate line external lead terminal, and the source line external lead terminal, and the pixel electrode 103, The gate line external lead terminal uppermost layer electrode and the source line external lead terminal uppermost layer electrode are formed by photolithography and etching.

Note that a slit pattern 150 is provided in the pixel electrode in order to control the alignment of the liquid crystal molecules. The contact hole 109 connects the TFT drain electrode 106a, the pixel electrode 103, and the force drain extraction electrode 106b.

With the above manufacturing method, in the active matrix substrate 130, the source line 102 and the pixel electrode 103 can be separated with the interlayer insulating films 115 and 120 interposed therebetween.

[0018] By the manufacturing method in which the source line 102 and the pixel electrode 103 are separated as described above, a decrease in yield due to a short circuit between the pixel electrode 103 and the source line 102 can be prevented. At the same time, as shown in FIG. 7, the pixel electrode 103 and the source line 102 can be overlapped with each other as viewed from above, so that the aperture ratio of the liquid crystal display device is improved.

Next, the color filter substrate 210 of the MVA type display device will be described with reference to FIGS. 9 and 10. FIG. 9 is a plan view showing one pixel in the color filter substrate 210 of the MVA type display device and a part of the pixels located adjacent to the one pixel. FIG. 10 is a cross-sectional view of the color filter substrate 210 corresponding to the cross section taken along the line D1-D2 of FIG.

[0020] The color filter substrate 210 typically has three primary colors (red, green, blue) on the transparent substrate 200. A coloring layer 220 and a black matrix layer (hereinafter referred to as BM) 221 such as a color filter layer 222 that has power, a counter electrode 223 such as ITO, an alignment film (not shown), and a protrusion 224 for alignment control .

[0021] On the transparent substrate 200, a negative type tantalum-based photosensitive resin solution in which carbon fine particles are dispersed is applied by spin coating, and then dried to form a black photosensitive resin layer. Subsequently, after the black photosensitive resin layer is exposed through a photomask, development is performed to form BM221. At this time, openings for the first colored layer are respectively formed in regions where the first colored layer (for example, red layer), the second colored layer (for example, green layer), and the third colored layer (for example, blue layer) are formed. The BM is formed so that the opening for the second colored layer and the opening for the third colored layer are formed. Each opening is formed to correspond to the pixel electrode of the active matrix substrate.

[0022] Next, after applying a negative acrylic photosensitive resin solution in which a pigment is dispersed by spin coating, drying is performed, and exposure and development are performed using a photomask, whereby the first colored layer is coated. A red layer is formed at the position of the opening.

Thereafter, the second color layer (for example, the green layer) and the third color layer (for example, the blue layer) are similarly formed, and the color filter layer 222 is completed. Further, a transparent electrode 223 having a power such as ITO is formed by sputtering. After that, a photosensitive positive type phenol novolak photosensitive resin solution is applied by spin coating, and then dried, exposed and developed using a photomask to form vertical alignment control protrusions 224. As a result, the color filter substrate is formed.

[0024] It should be noted that a slit pattern is used to control the alignment of liquid crystal molecules in the same manner as the pixel electrode 103 of the active matrix substrate 130, instead of the vertical alignment control protrusion 224 provided on the MVA color filter substrate 210. May be provided. On the other hand, instead of forming the slit pattern 150 on the pixel electrode 103 provided on the active matrix substrate 130, the same alignment control projection as that provided on the color filter substrate 210 may be provided.

By the way, in the above-described color filter substrate and active matrix substrate, a transparent conductive film is an essential component, and ITO (indium oxide containing tin), IZO (indium oxide containing zinc). ) And other electrode materials. However, such transparency Since the bright conductive film contains indium which is a rare metal, it is expensive and is likely to be insufficiently supplied. Therefore, there is a problem that the production of the color filter substrate and the active matrix substrate is hindered. In contrast, zinc oxide (hereinafter referred to as ZnO) has the advantage of being abundant in resources. For example, Patent Document 2 describes the use of ZnO as a transparent electrode.

Patent Document 1: Japanese Patent Laid-Open No. 11-242225 (published on September 7, 1999)

Patent Document 2: JP-A-62-124530 (published on June 5, 1987)

Disclosure of the invention

However, in the configuration and manufacturing method of the active matrix substrate and the color filter substrate, when ZnO is used for the transparent electrode film, there is a problem that the corrosion resistance (erosion resistance) is low. .

[0027] More specifically, it is as follows. A liquid crystal panel is formed by forming an alignment film on an active matrix substrate and a color filter substrate, and then injecting and sealing a liquid crystal material by bonding the substrates together. However, if the foreign matter adhering to both substrates is not sufficiently removed at this time, the panel yield and display quality will be reduced, such as liquid crystal alignment failure due to foreign matter and repelling of the alignment film due to substrate contamination. Cause it. Therefore, cleaning with an alkaline solution is performed before the two substrates are bonded together, but there is a problem that ZnO is eroded at this time.

[0028] Such problems are caused by various display devices such as non-MVA liquid crystal display devices, EL (Electro Luminescence) display devices, plasma display devices, etc. It can occur on a substrate provided with a conductive layer of a transparent electrode that is subjected to a cleaning step using an alkaline solution, such as a photoelectric conversion device such as a battery or a touch panel.

[0029] The present invention has been made to solve the above-described problems, and includes a substrate having a conductive layer in which zinc oxide is hardly eroded even when resource-rich zinc oxide is used. It is an object of the present invention to provide a manufacturing method of a substrate provided with a display device and a conductive layer.

[0030] In order to solve the above problems, the present invention includes a laminated structure in which a plurality of conductive layers including at least a first conductive layer mainly composed of zinc oxide are stacked on a substrate, and a cleaning liquid is used in a cleaning step. The second conductive layer having a surface in contact with the conductive layer, wherein the material of the second conductive layer constituting the laminated structure is higher in erosion resistance against the cleaning liquid than zinc oxide. It is a board | substrate provided with this.

[0031] According to the above invention, even when the first conductive layer mainly composed of zinc oxide, which is excellent in economic efficiency, is used, the first conductive layer is hardly eroded by the cleaning liquid by the laminated structure.

[0032] Further, the substrate provided with the conductive layer of the present invention is characterized in that the second conductive layer is made of ITO or IZO.

[0033] According to the above configuration, a conventional manufacturing process similar to that in the case where the conductive layer is only ITO or IZO can be used, and a portion where the conventional manufacturing process can be used is as follows. New manufacturing process development is not required. Further, as a result of forming the first conductive layer mainly composed of zinc oxide, the amount of ITO used to form the second conductive layer can be adjusted.

Furthermore, the substrate provided with the conductive layer of the present invention is characterized in that the first conductive layer is thicker than the second conductive layer.

[0035] According to the above configuration, the amount of indium, which is a rare metal, can be suppressed, and stable production and supply can be achieved without being affected by the supply amount of indium.

The substrate provided with the conductive layer of the present invention is characterized in that the plurality of conductive layers serve as pixel electrodes and constitute an active matrix substrate.

[0037] According to the above invention, even if a layer mainly composed of zinc oxide, which is economical, is used for the pixel electrode, the layer mainly composed of zinc oxide is hardly eroded in the cleaning process. Therefore, good display quality can be obtained and the yield can be improved.

[0038] The substrate provided with the conductive layer of the present invention is characterized in that the plurality of conductive layers serve as transparent electrodes to constitute a color filter substrate.

[0039] According to the above invention, even when a layer mainly composed of zinc oxide, which is excellent in economic efficiency, is used for the transparent electrode, the layer mainly composed of zinc oxide is hardly eroded in the cleaning process. Therefore, good display quality can be obtained and the yield can be improved.

[0040] A substrate provided with the conductive layer of the present invention is characterized in that it has an alignment control protrusion on the second conductive layer side of the laminated structure.

[0041] According to the above configuration, the wide viewing angle display device base used in the MVA liquid crystal display device is used. A board can be obtained.

[0042] A substrate having a conductive layer according to the present invention is characterized in that a plurality of conductive layers including at least a first conductive layer mainly composed of zinc oxide have slits.

[0043] According to the above configuration, a substrate for a wide viewing angle display device used in an MVA liquid crystal display device can be obtained.

[0044] A display device of the present invention is characterized by using a substrate including any one of the conductive layers described above.

[0045] According to the above configuration, a conventional manufacturing process can be used by using the substrate including the conductive layer of the present invention for a display device. As a result, stable production can be secured at low cost, and a display device with a high aperture ratio, a wide viewing angle, and a high yield can be supplied.

[0046] A method for producing a substrate provided with a conductive layer of the present invention includes a step of forming a conductive layer on the substrate, and a step of cleaning in a state where at least a part of the conductive layer of the substrate is exposed, The conductive layer forming step is a step of forming a conductive layer containing zinc oxide as a main component on a substrate and a conductive layer having a surface in contact with the cleaning liquid, and is resistant to erosion with respect to the cleaning liquid. And a step of forming a conductive layer made of a material higher than zinc.

[0047] According to the above invention, even when the first conductive layer mainly composed of zinc oxide, which is excellent in economic efficiency, is used, the first conductive layer is hardly eroded by the cleaning liquid during the cleaning process.

In the present specification, erosion means that at least a part is removed by a liquid such as a cleaning liquid, and erosion resistance means resistance against such erosion.

[0049] According to the present invention, since the second conductive layer having high erosion resistance to the cleaning liquid exists even when the first conductive layer mainly composed of zinc oxide, which is excellent in economic efficiency, is used, The conductive layer is not easily eroded by the cleaning solution. Therefore, it is possible to suppress the decrease in yield and quality, and to achieve substrate supply by stable production at low cost.

Brief Description of Drawings

FIG. 1 is a cross-sectional view showing a schematic structure of a first embodiment of a display device substrate (active matrix substrate) in a liquid crystal display device according to the present invention.

[FIG. 2] One pixel and its periphery in the active matrix substrate for display device of Embodiment 1. It is a top view which shows schematic structure of a side part.

3 is a cross-sectional view taken along line A1-A2 of the display device substrate shown in FIG.

FIG. 4 is a cross-sectional view showing a schematic structure of Embodiment 2 of a display device substrate (color filter substrate) in a liquid crystal display device according to the present invention.

FIG. 5 is a plan view showing a schematic structure of one pixel and its peripheral portion in the color filter substrate for display device of Embodiment 2.

6 is a cross-sectional view taken along line B1-B2 of the display device substrate shown in FIG.

FIG. 7 is a plan view showing a conventional active matrix substrate for a display device.

8 is a cross-sectional view taken along line C1 C2 of the display device substrate shown in FIG.

FIG. 9 is a plan view showing a conventional color filter substrate for a display device.

10 is a cross-sectional view taken along line D1-D2 of the display device substrate shown in FIG.

Explanation of symbols

1 Gate line (scanning line)

2 Source line (signal line)

3 Pixel electrode (laminated structure)

3a Upper pixel electrode (second conductive layer, ITO layer)

3b Lower layer pixel electrode (first conductive layer, ZnO layer)

4 Gate electrode

5 Source electrode

6a Drain electrode

6b Drain lead wiring

7 Auxiliary capacity line

8 Orientation control slit

9 Contact Honoré

10 Insulating substrate

11 Gate insulation film

12 Active semiconductor layer

13 Low resistance semiconductor layer 14 Switching elements

15 Upper interlayer insulation film

20 Lower interlayer insulation film

30 Active matrix substrate (Substrate with conductive layer, display device substrate) 31 Color filter layer

33 Color filter substrate (substrate with conductive layer, substrate for display device)

34 Colored layer

35 Shading layer (BM)

36 Protrusion for orientation control

37 Transparent electrode (laminated structure)

37a Upper transparent electrode (second conductive layer, ITO layer)

37b Lower transparent electrode (first conductive layer, ZnO layer)

40 Liquid crystal display

BEST MODE FOR CARRYING OUT THE INVENTION

[Embodiment 1]

An embodiment of the present invention will be described with reference to FIGS.

In this embodiment, an active matrix substrate for a liquid crystal display device will be described as a specific example of the substrate for a display device.

FIG. 1 is a cross-sectional view showing an example of a liquid crystal display device using the active matrix substrate of the present invention. The liquid crystal display device 40 includes an active matrix substrate 30 and a color filter substrate 33, and the substrates 30 and 33 sandwich a liquid crystal layer 32 made of liquid crystal such as vertical alignment type liquid crystal, for example. The active matrix substrate 30 includes a pixel electrode 3 (laminated structure) in which an oxide zinc (ZnO) layer 3b (first conductive layer) and an ITO layer 3a (second conductive layer) are stacked. The color filter substrate 33 includes a color filter layer including a colored layer 34 and a light-shielding film 35, protrusions for controlling the pretilt of liquid crystal molecules that control liquid crystal alignment (protrusions for alignment control) 36, and transparent electrodes 37 etc.

As shown in FIG. 4, the transparent electrode 37 is preferably a laminated structure in which a ZnO layer 37b (first conductive layer) and an ITO layer 37a (second conductive layer) are laminated. The liquid crystal layer 32 is It is sandwiched between an alignment film (not shown) of the direction substrate (color filter substrate) 33 and an alignment film (not shown) of the active matrix substrate 30.

FIG. 2 is a plan view showing one pixel in the active matrix substrate 30 (display device substrate) of the present invention and a part of the pixels located adjacent to the one pixel. As shown in FIGS. 2 and 3, a source line (signal line) 2, a gate line (scanning line) 1, and a pixel electrode 3 are stacked on an insulating substrate 10. The gate line 1 and the source line 2 are arranged so as to cross each other. A switching element (TFT) 14 and a pixel electrode 3 are provided at each intersection where they intersect. Note that the insulating substrate 10 is located on the rearmost surface in FIG. 2, and is disposed at the position described in the cross-sectional view shown in FIG. 3 is a cross-sectional view taken along the line Al—A2 in FIG.

The gate line 4 is connected to the gate line 1! A source electrode 5 is connected to the source line 2. Further, in FIG. 3, the pixel electrode 3 is formed by stacking a ZnO layer 3b as a lower layer and an ITO layer 3a as an upper layer. The pixel electrode 3 is connected to the drain electrode 6a via the contact hole 9 provided in the interlayer insulating film 15 and the drain extraction electrode 6b. The pixel electrode 3 is provided with a slit 8 for controlling the alignment of the liquid crystal. Further, the drain extraction electrode 6b is opposed to the auxiliary capacitance bus line 7 across the gate insulating film 11, thereby forming an auxiliary capacitance.

Next, current and voltage control will be briefly described. When the gate line 1 is selected, a voltage is applied to the gate electrode 4. The current flowing between the source electrode 5 and the drain electrode 6a is controlled by the voltage applied to the gate electrode 4. That is, based on the signal transmitted from the source line 2, current flows from the source electrode 5 to the drain electrode 6a, and further from the drain electrode 6a to the pixel electrode 3 via the drain extraction electrode 6b. Flows. Thereby, the pixel electrode 3 applies a voltage to the liquid crystal layer 32 to perform a predetermined display. The auxiliary capacity bus line 7 is provided as an auxiliary to maintain a predetermined display.

Next, a method for manufacturing the active matrix substrate 30 will be described with reference to FIGS.

[0060] First, TiZAlZTi is formed on an insulating substrate 10 having a transparent insulating force such as glass. The laminated film is formed by sputtering, photolithography is performed, dry etching and resist peeling are performed, and the gate line 1, the gate electrode 4, and the auxiliary capacitance line 7 are formed simultaneously.

[0061] Next, on those surfaces, a gate insulating film 11 made of 3000A to 5000A SiN (silicon nitride film), an active semiconductor layer 12 having an amorphous silicon force of about 1500A to 3000A, and An n-type low-resistance semiconductor layer 13 of about 500 A to 1000 A doped with phosphorus is formed, and photolithography, dry etching, and resist stripping are performed to form an island-shaped semiconductor layer 25.

[0062] Here, the gate insulating film 11 is formed by using a mixed gas of SiH gas, NH gas, and N gas.

4 3 2

The active semiconductor layer 12 uses a mixed gas of SiH gas and H gas, and further has an n-type low resistance.

4 2

The semiconductor layer 13 uses a mixed gas of SiH gas, PH gas, and H gas.

4 3 2

Films are continuously formed by chemical vapor deposition.

[0063] Further, a laminated film made of TiZAlZTi is formed by sputtering, photolithography is performed, and dry etching is performed to simultaneously form the source line 2, the source electrode 5, the drain electrode 6a, and the drain extraction electrode 6b. . Further, the n-type semiconductor layer 13 is continuously subjected to source / drain separation etching to remove the resist. At this time, a thin film transistor (TFT) is formed.

Next, 1000 A to 5000 A @ i (lower interlayer insulating film 20 made of SiN is formed by CVD using a mixed gas of SiH gas, NH gas, and N gas so as to cover the entire surface. .

4 3 2

[0065] After that, the upper organic layer insulating film 15 made of a positive photosensitive acrylic resin having a thickness of about 2 μm to 4 μm is formed on the contact hole 9 and the gate line external lead terminal contact pattern by photolithography. Also, it is formed so as to have a pattern for contact with the external lead terminal of the source line.

[0066] Next, in order to form the contact hole 9, the gate line external lead terminal, and the source line external lead terminal, the lower interlayer insulating film 20 and the gate insulating film 11 are formed using the upper organic layer insulating film 15 as a mask. Dry Ettin using mixed gas of CF gas and O gas

4 2

Etch continuously by etching.

[0067] Thereafter, a ZnO film and an ITO film are formed by sputtering so as to cover the contact hole 9 To do. First, a ZnO film is mixed with Ar and O using an RF power source sputtering system with a power of 15 kW, a substrate temperature of 210 ° C, and a pressure of 1.2 Pa (Ar flow rate: O flow rate = 2-3: 1) Using

twenty two

To 900A. Next, a mixed gas of Ar, O, and H 2 O (Ar flow rate: O flow rate: H) is applied to the ITO film at room temperature, power of 25 kW, and pressure of 1.2 Pa using a DC power source sputtering system.

2 2 2 2

The film is formed at 200 A using O flow rate = 20: 1: 1 to 2). Then, a photosensitive resist is applied, the photosensitive resist is exposed by photolithography, and then developed with a developer and patterned. Furthermore, using the pattern formed by patterning as a mask, the deposited ZnO film and ITO film are patterned by wet etching using an etching solution that also has phosphoric acid, nitric acid and acetic acid, and then the resist is removed using a stripping solution. The pixel electrode 3 is formed by peeling. In this embodiment, an aqueous solution having a TMAH (hydroxyl tetramethylammonium) concentration of 10% or less is used as the developer. As the stripping solution, a mixed solution of MEA (monoethanolamine) and DMSO (dimethyl sulfoxide) (mixing ratio MEA: DMSO = 2 to 3: 1) was used. In this etching process, the same etchant is used to etch the gap between the ZnO film and the ITO film.

As described above, the active matrix substrate 30 in the present embodiment is obtained. By bonding the active matrix substrate 30 and the color filter substrate 33 so as to face the active matrix substrate 30, a liquid crystal panel is formed. At this time, first, both substrates are prepared and each is washed with an alkaline solution. In this embodiment, alkaline hydrogen water (alkaline reduced water) having a pH power of about 12 to 12 was used as the cleaning liquid. Alkaline hydrogen water can be prepared by dissolving the hydrogen gas in pure water, it is obtained by the _P H to Anorekari with ammonia or the like. After cleaning, an alignment film is formed on each substrate, and liquid crystal is injected and sealed between the substrates to form a liquid crystal panel, and a driver or the like is connected to an external lead terminal of the liquid crystal panel. More liquid crystal display devices are manufactured.

In the present embodiment, TiZA lZTi is used as the material of the gate line 1 and the source line 2. However, the material for the gate line 1 and the source line 2 may be any metal that provides the desired line resistance. For example, a metal such as tantalum (Ta), titanium (Ti), chromium (Cr), aluminum (A1), or an alloy of these metals may be used as the material for the gate line 1 and the source line 2. In addition, products such as TaNZTaZTaN It is also possible to use a film having a layer structure force as a material for the gate line 1 and the source line 2. Furthermore, as a material for the source line 2, for example, a transparent conductive film such as ITO can be used, in addition to a general metal film.

In this embodiment, a slit is provided on the pixel electrode in order to control the pretilt of the liquid crystal molecules. However, instead of providing a slit, it is similar to the alignment control protrusion provided on the color filter substrate. Alternatively, alignment control protrusions using a photosensitive resist may be provided. The details of the color filter substrate on which the orientation control protrusion is provided will be described later. For the photosensitive resist, phenol novolac resin is used.

In this embodiment, an amorphous silicon thin film transistor is used as the switching element (TFT) 14. However, as the switching element 14, for example, a microphone opening crystal silicon thin film transistor, a polysilicon thin film transistor, a CG silicon (continuous grain boundary crystal silicon) thin film transistor, a MIM (Metal Insulator Metal), and the like can be used similarly.

Furthermore, the pixel electrode 3 uses a ZnO layer 3b as a lower layer and an ITO layer 3a as an upper layer as a laminated film. However, electrode materials such as IZO, InO, and TiO can be used for the upper layer of the laminated film instead of the ITO layer 3a as long as the lower ZnO layer 3b can be protected with the cleaning fluid force. Further, if the thickness of the ITO layer 3a is 200A, the lower ZnO layer 3b may be thinner than 200A if the erosion power by the cleaning liquid can be protected. Further, the pixel electrode 3 of the present embodiment may contain a different element such as A1 or Ga as a dopant in the force of using ZnO in the conductive layer mainly composed of zinc oxide. By doping these elements, etc., the effect of reducing the resistance is achieved.

[0073] In addition, the pixel electrode 3 may be a laminated film of two or more layers, not only a laminated film composed of two layers.

In addition, a positive acrylic photosensitive transparent resin was used for the upper interlayer insulating film 15. However, it is not limited to this. For example, negative photosensitive resin and SiO (acid key)

A material capable of obtaining a desired dielectric constant, transmittance, and etching selectivity between the lower interlayer insulating film 15 and the gate insulating film 11 can be used for the upper interlayer insulating film 15. In addition, for the lower interlayer insulating film 20, a force positive type or negative type using SiN film by CVD method is used. May be used. Furthermore, the protective film may also be a photosensitive transparent resin made of only SiNjI or a SiO film. In addition, as photosensitive transparent resin,

2

For example, there may be mentioned resin such as acrylic resin, epoxy resin, polyurethane resin, and polyimide resin.

[0075] Further, the cleaning liquid for the active matrix substrate is not limited to the alkaline hydrogen water of the present embodiment. For example, the aqueous solution of sodium hydroxide, aqueous solution of tetraammonium hydroxide, aqueous solution of potassium hydroxide, A sodium salt aqueous solution of a fatty acid may be used.

In the pixel electrode 3 and the interlayer insulating film, the “lower layer” is disposed on the insulating substrate 10 side, the layer is disposed on the liquid crystal layer 32 side, and the “upper layer” is disposed on the liquid crystal layer 32 side. Indicates the layer.

Further, the display device is not limited to the liquid crystal display device. For example, the active matrix substrate 30 in the present embodiment and the color filter substrate 33 are arranged so as to face the active matrix substrate, An organic EL display device can be configured by arranging an organic EL layer between the substrate and an organic EL panel, and connecting a driver to the external lead terminal of the panel.

[Embodiment 2]

The following will describe another embodiment of the present invention with reference to FIGS. In the present embodiment, a color filter substrate 33 for a liquid crystal display device will be described as a specific example of the display device substrate. In the second embodiment, an example will be described in which the present invention is applied to a power filter substrate provided with alignment control protrusions for dividing and controlling the alignment state (pretilt) of liquid crystal within a pixel. In the present embodiment, the present invention can also be applied to a configuration in which a force black matrix is not provided, which is described when a black matrix is provided on the color filter substrate 33. For convenience of explanation, members having the same functions as those shown in the drawing of FIG.

FIG. 4 is a cross-sectional view showing an example of the liquid crystal display device of the present invention. The liquid crystal display device 40 includes an active matrix substrate 30 and a color filter substrate 33, and the substrates 30 and 33 sandwich a liquid crystal layer 32 made of liquid crystal such as vertical alignment type liquid crystal, for example. The active matrix substrate 30 includes a pixel electrode 3 in which a ZnO layer 3b and an ITO layer 3a are stacked. The color filter substrate 33 includes a colored layer 34, a color filter layer of the light-shielding film 35, a protrusion (control for alignment control) 36 for controlling the pretilt of liquid crystal molecules for controlling the alignment of the liquid crystal, and a ZnO layer 37b. And a transparent electrode 37 in which an ITO layer 37a is laminated. The liquid crystal layer 32 is sandwiched between an alignment film (not shown) of the counter substrate (color filter substrate) 33 and an alignment film (not shown) of the active matrix substrate 30.

FIG. 5 is a plan view showing one pixel in the color filter substrate 33 of the present embodiment and a part of the pixels located adjacent to the one pixel. FIG. 6 is a cross-sectional view of the color filter substrate 33 corresponding to the cross section taken along line Bl-B2 of FIG.

[0081] The color filter substrate 33 is formed on the transparent substrate 10, typically, a color filter layer 31 composed of three primary colors (red, green, and blue) 34 and BM35, a ZnO layer 37b, and an ITO layer. A counter electrode (transparent electrode) 37 on which layers 37a are stacked, an alignment film (not shown), and a protrusion 36 for alignment control. Note that the transparent substrate 10 is located at the rearmost surface in FIG. 5, and is disposed at the position described in the cross-sectional view shown in FIG.

Hereinafter, a method for manufacturing the color filter substrate 33 in the present embodiment will be described.

On the transparent substrate 10, after applying a negative type tantalum-based photosensitive resin solution in which fine carbon particles are dispersed by spin coating, drying is performed to form a black photosensitive resin layer. Subsequently, the black photosensitive resin layer is exposed through a photomask and then developed to form 2. 35 μm of ΒΜ35. At this time, openings for the first colored layer are respectively formed in regions where the first colored layer (for example, red layer), the second colored layer (for example, green layer), and the third colored layer (for example, blue layer) are formed. B M35 is formed so that an opening for the second colored layer and an opening for the third colored layer are formed. Each opening is formed so as to correspond to the pixel electrode of the active matrix substrate.

[0084] Next, after applying a negative acrylic photosensitive resin solution in which a pigment is dispersed by spin coating, drying is performed, and exposure and development are performed using a photomask. Form.

[0085] Thereafter, the second color layer (for example, the green layer) and the third color layer (for example, the blue layer) are similarly formed, and the color filter layer 31 is completed.

[0086] Further, the laminated transparent electrode 37 having the lower layer force ηθ layer 37b and the upper layer made of the ITO layer 37a is scanned. A film is formed by a knotter. First, a ZnO film was sputtered using an RF power source system at a power of 15 kW, a substrate temperature of 210 ° C, a pressure of 1.2 Pa, and a mixed gas of Ar and O (Ar flow rate: O flow rate = 2

twenty two

~ 3: 1) is used to form a film at 900A. Next, the ITO film was mixed with Ar, O, and H 2 O (Ar flow rate) at room temperature, power of 25 kW, and pressure of 1.2 Pa using a DC power source sputtering system.

twenty two

: 0 flow rate: H 2 O flow rate = 20: 1: 1-2), 200

2 2 A film is formed.

[0087] Next, after applying a photosensitive positive type phenol novolak photosensitive resin solution by spin coating, drying, exposure using a photomask, development using a TMAH developer, 1. Form a 5 m vertical alignment control protrusion 36. As a result, the color filter substrate 33 is formed.

A liquid crystal panel is formed by bonding the color filter substrate 33 and the active matrix substrate 30 so as to face the color filter substrate 33. At this time, first, both substrates are prepared, and each is washed with an alkaline solution. In this embodiment, alkaline hydrogen water (alkaline reduced water) having a pH of about 8 to 12 was used as the cleaning liquid. After cleaning, an alignment film is formed on each substrate, and liquid crystal is injected and sealed between the substrates to form a liquid crystal panel, and a driver or the like is connected to an external lead terminal of the liquid crystal panel. More liquid crystal display devices are manufactured.

With the above configuration, as shown in FIG. 6, according to the second embodiment, the ITO layer 37a is separately formed on the ZnO layer 37b that forms the transparent electrode 37. The transparent electrode 37 that is not eroded is not eroded, and the display is not defective.

In the transparent electrode 37 of this embodiment, a ZnO layer is used as a conductive layer mainly composed of zinc oxide, but different elements such as A1 and Ga may be contained in ZnO as a dopant. A low-resistance transparent electrode can be obtained by doping these elements.

Further, the cleaning liquid for the active matrix substrate 30 is not limited to the alkaline hydrogen water of the present embodiment. For example, the aqueous solution of sodium hydroxide, aqueous solution of tetraammonium hydroxide, aqueous solution of potassium hydroxide and potassium hydroxide is used. It may be an aqueous sodium salt solution of fatty acid.

In the transparent electrode 37, “lower layer” refers to a layer disposed on the insulating substrate 10 side, and “upper layer” refers to a layer disposed on the liquid crystal layer 32 side.

Further, the vertical alignment control protrusion 3 provided on the MVA type color filter substrate 33. Instead of 6, a slit pattern may be provided to control the orientation of the liquid crystal molecules in the same way as the active matrix pixel electrode. In this case, the slit can be formed in the transparent electrode 37 by the same method as the method of forming the slit 8 provided in the pixel electrode 3 of the active matrix substrate 30 shown in the first embodiment. That is, first, a ZnO film and an ITO film are formed by sputtering, a photosensitive resist is applied, the photosensitive resist is exposed by photolithography, and then developed with a developer and patterned. Furthermore, using the pattern formed by patterning as a mask, the deposited ZnO film and ITO film were patterned by wet etching using an etching solution consisting of phosphoric acid 'nitric acid' acetic acid, and then using a stripping solution. The transparent electrode 37 is formed by removing the resist. In Embodiment 2 as well, an aqueous solution having a TMAH (hydroxyl tetramethylammonium) concentration of 10% or less is used as the developer, and MEA (monoethanolamine) is used as the stripper. A mixed solution with DMSO (dimethyl sulfoxide) (mixing ratio MEA: DMSO = 2 to 3: 1) was used. Moreover, in the above-described etching process, the same etchant is used to etch the gap between the ZnO film and the ITO film.

Further, the transparent electrode 37 uses a ZnO layer 37b as a lower layer and an ITO layer 37a as an upper layer as a laminated film. However, transparent pixel electrode materials such as IZO, InO, and TiO can also be used for the upper layer of the laminated film as long as the lower ZnO layer 37b can protect the erosion power by the cleaning liquid. Also, if the thickness of the ITO layer 37a is 200A, the lower ZnO layer 37b can be protected from the erosion by the cleaning solution, but it is thinner than 200A.

[0095] In addition, the transparent electrode 37 may be a laminated film of three or more layers, not only a laminated film consisting of two layers.

In the second embodiment, the active matrix substrate described in the first embodiment is used. However, for example, a substrate made of an ITO single layer cover may be used as the pixel electrode 3. However, since the effects of the present invention can be obtained on both substrates, it is preferable to apply the present invention to both substrates as in the second embodiment.

Note that the display device is not limited to the liquid crystal display device. For example, the color filter substrate 33 in the present embodiment and the active matrix substrate 30 are arranged so as to face the color filter substrate 33, and Yes, by placing an organic EL layer between the substrate It is also possible to configure an OLED display device by connecting it to the external lead terminal of the panel and connecting it with a driver.

[0098] In the first and second embodiments, the power described above for the MVA type liquid crystal display device is not limited to this. A liquid crystal display device other than the MVA system, an EL display device, The present invention can be applied to substrates including a transparent electrode conductive layer subjected to a cleaning process, such as various display devices such as plasma display devices, photoelectric conversion devices such as solar cells, and touch panels.

[0099] (Other configurations)

In addition, this invention is realizable as the following structures.

[0100] (First configuration)

A substrate provided with a conductive film formed by laminating a plurality of conductive layers,

The conductive film is

At least a first conductive layer mainly composed of zinc oxide and a second conductive layer stacked on the opposite side of the substrate with respect to the first conductive layer,

The second conductive layer is

The substrate characterized by having higher erosion resistance to the detergent used for cleaning the substrate than the first conductive layer.

[0101] (Second configuration)

The second conductive layer is

The substrate according to the first structure, which is made of ITO or IZO.

[0102] (Third configuration)

The first conductive layer is

2. The substrate according to the first configuration, wherein the substrate is thicker than the second conductive layer.

[0103] (Fourth configuration)

The conductive film is

The substrate according to the first structure, which is used as a pixel electrode in an active matrix substrate.

[0104] (Fifth configuration) The conductive film is

The substrate according to the first configuration, which is used as a transparent electrode in a color filter substrate.

[0105] (Sixth configuration)

The conductive film is

The substrate according to the first configuration, characterized in that an alignment control protrusion is provided on the surface. (Seventh configuration)

The conductive film is

The substrate according to the first configuration, wherein a slit is provided on the surface.

[0106] (Eighth configuration)

First configuration force A display device comprising the substrate according to one configuration of the seventh configuration, the displacement force.

[0107] (Ninth Configuration)

A method for manufacturing a substrate having a conductive film formed by laminating a plurality of conductive layers, the first conductive layer forming step forming a first conductive layer comprising zinc oxide as a main component and constituting the conductive film; ,

A second conductive layer having higher erosion resistance than the first conductive layer with respect to a substance used for a chemical treatment applied to process the conductive film, and the substrate with respect to the first conductive layer. A second conductive layer forming step for forming the second conductive layer, and a substrate on which the conductive film is formed by the first conductive layer forming step and the second conductive layer forming step. Cleaning process,

The method for manufacturing a substrate, wherein the second conductive layer has a high V erosion resistance to a detergent used in the cleaning step.

Industrial applicability

The present invention can be effectively applied to a substrate provided with a conductive layer and to be cleaned in a manufacturing process. In particular, it can be suitably applied to a substrate provided with a pixel electrode or a transparent electrode used in a liquid crystal panel.

Claims

The scope of the claims

[1] A laminated structure in which a plurality of conductive layers including at least a first conductive layer mainly composed of zinc oxide is laminated on a substrate,

A substrate provided with a conductive layer, wherein the material of the second conductive layer of the laminated structure located on the surface in contact with the cleaning liquid in the cleaning step has higher erosion resistance to the cleaning liquid than zinc oxide.

2. The substrate having a conductive layer according to claim 1, wherein the second conductive layer has an ITO or IZO force.

[3] The substrate having a conductive layer according to claim 1 or 2, wherein the first conductive layer is thicker than the second conductive layer.

4. The substrate provided with the conductive layer according to claim 1, wherein the plurality of conductive layers serve as pixel electrodes and constitute an active matrix substrate.

5. The substrate provided with the conductive layer according to any one of claims 1 to 3, wherein the plurality of conductive layers serve as transparent electrodes and constitute a color filter substrate.

6. The substrate provided with the conductive layer according to any one of claims 1 to 5, wherein an alignment control protrusion is provided on the second conductive layer side of the multilayer structure.

7. The substrate having a conductive layer according to claim 1, wherein the plurality of conductive layers have slits.

[8] A display device using a substrate comprising the conductive layer according to any one of [1] to [7].

[9] forming a conductive layer on the substrate;

Washing with at least a portion of the conductive layer of the substrate exposed, and the conductive layer forming step includes forming a conductive layer mainly composed of zinc oxide on the substrate;

And a step of forming a conductive layer of a material having a higher erosion resistance to the cleaning liquid than zinc oxide on a surface in contact with the cleaning liquid.