JP4122875B2 - Method for manufacturing plasma display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a matrix type display device having an image display function, and more particularly to a method for manufacturing a plasma display panel .
[0002]
[Prior art]
FIG. 6 shows an outline of an AC type plasma display panel structure which is one of the well-known flat type display devices.
[0003]
The AC type plasma display panel includes a front plate 100 and a back plate 110. The front plate 100 includes a row electrode 104, a dielectric layer 105, and a protective layer 106 that are sequentially formed on a glass substrate 101. The row electrode 104 includes a scan electrode 102 and a sustain electrode 103. The scan electrode 102 and the sustain electrode 103 are transparent electrodes 102a and 103a, and bus electrodes 102b and 103b formed in contact with the transparent electrodes 102a and 103a, respectively. Is provided. Note that a plurality of row electrodes 104 are formed in parallel to one side of the glass substrate 101 with black stripes 107 interposed therebetween.
[0004]
On the other hand, the back plate 110 includes column electrodes 112, an insulator layer 113, barrier ribs 114, and phosphors 115 that are sequentially formed on a glass substrate 111. The phosphors 115 are separated by the barrier ribs 114, and the red phosphor 115a, the green phosphor 115b, and the blue phosphor 115c constitute one pixel.
[0005]
As shown in FIG. 7, the front plate 100 and the back plate 110 are arranged with the row electrodes 104 and the column electrodes 112 facing each other, and are bonded together using a sealing material such as frit glass. Then, a degassing process is performed while heating, and an inert gas containing xenon as a main component is sealed in a gap 120 provided between them to complete a plasma display panel .
[0006]
In a plasma display panel, it is common to add two types of metal wiring patterns of bus electrodes 102b and 103b and column electrode 112 in order to lower the resistance values of scan electrode 102 and sustain electrode 103 constituting row electrode 104. is there.
[0007]
That is, since a relatively large current flows through the bus electrodes 102b and 103b, in order to reduce the resistance value, the electrodes and wirings are formed in a multilayer structure to increase the electrode thickness of the bus electrodes 102b and 103b. In addition, although not shown in the drawings as another method for reducing the electrode and wiring resistance values, the electrode width and the wiring width are also increased, but this method affects the degree of integration. Since the bus electrodes 102b and 103b affect the external light reflection characteristics of the panel surface, it is necessary to take measures such as blackening. However, it is said that the column electrode 112 is less likely to be reduced in resistance or blackened than the row electrode 104.
[0008]
Under these circumstances, as these metal wiring pattern materials, it is common to use a silver-based alloy for low resistance or to adopt a three-layer structure of Cr / Cu / Cr using inexpensive copper. .
[0009]
The dielectric layer 105 formed on the front plate 100 is formed by applying a glassy resin containing silicon oxide (SiO ₂ ) as a main component in a film thickness of 30 μm to 40 μm and heating and curing. Further, as the protective layer 106, magnesium oxide (MgO) is formed to a film thickness of 0.4 μm to 1 μm by a film forming method such as electron beam evaporation. The insulator layer 113 formed on the back plate 110 is formed by applying a glassy resin mainly composed of SiO ₂ to a thickness of about 10 μm.
[0010]
In order to manufacture the plasma display panel, for example, the dielectric layer 105 is formed on the front plate 100, and the insulator layer 113 is formed on the back plate 110, for example. The film thickness of these layers is 10 μm to 40 μm, and the film is formed in the image display portion. Therefore, the glass powder mainly composed of SiO ₂ , the binder resin and the diluent solvent are used. A thick glass resin made of a mixed solution is selectively applied to the image display portion, and is formed through a vitrification step by heating and baking.
[0011]
For selective application of such a thick film resin, a coating machine 30 called a slit coater (or die coat) shown in FIG. 8 is used. Although not shown when using the coating machine 30, the front substrate 100 is fixed on a stage with high flatness by means such as vacuum suction. Then, the applicator 30 is separated from the front substrate 100 by about 10 μm on the image display portion of the front substrate 100, and the glass resin 32 is dropped from the slits 31 while being scanned in parallel with one side of the front substrate 100. At this time, since the film thickness is shrunk due to evaporation of the solvent in the glass resin at the time of firing, the initial coating film thickness is preferably about 20 μm to 100 μm.
[0012]
Subsequently, the dielectric layer 105 is formed by heating and baking. The insulator layer 113 is also formed by a similar method. If the dropping amount of the glass resin 32 is not uniform in the width direction (W direction) of the coating machine 30 in the formation process of the dielectric layer 105 or the insulating layer 113, the scanning direction of the coating machine 30 is shown in FIG. A streaky film thickness spot 33 is generated. Even if the mechanical accuracy of the width t of the slit 31 is increased, the glass resin 32 having a high viscosity is accumulated at the tip portion of the slit 31, so that a streaky film thickness unevenness 33 is generated due to long-term use. It must be approved to some extent. Therefore, until now, it has been necessary to replace or clean the slit 31 as appropriate.
[0013]
Moreover, since the coating film thickness of the glass resin 32 has a relatively large film thickness of 20 μm to 100 μm, if the heating is performed rapidly in the heating and baking process, the solvent contained in the glass resin 32 bumps and causes pinholes. Therefore, in order to suppress the occurrence of these pinholes, the glass resin 32 is generally applied in a plurality of times.
[0014]
In addition, when the streaky film thickness unevenness 33 is generated in the dielectric layer 105 or the insulating layer 113, the brightness of the plasma display panel is streaked and the image quality is lowered. FIG. 9 is a cross-sectional view taken along line AA of the front substrate 101 to which the glass resin 32 is applied in FIG. When the glass resin is applied once, generally a film thickness unevenness 34 is generated. In the method of applying twice, as shown in FIG. 9, the film thickness unevenness 34 generated by the first application interferes with the film thickness unevenness 35 generated by the second application, and the maximum value and the maximum value of the film thickness coincide with each other. When the minimum value and the minimum value coincide with each other, a larger film thickness unevenness is caused, which is a major cause of deterioration in image quality.
[0015]
[Problems to be solved by the invention]
It is an object of the present invention to provide a method for manufacturing a plasma display panel with little film thickness unevenness when forming such a dielectric layer or insulator layer.
[0016]
[Means for Solving the Problems]
In order to achieve this object, in the plasma display panel manufacturing method of the present invention, when forming the dielectric layer or the insulating layer, the first coating layer and the second coating layer applied by a coating machine are formed. Apply at a predetermined angle to each other. As a result, it is possible to suppress the occurrence of streaky film thickness spots occurring in the dielectric layer or the insulator layer.
[0017]
That is, the present invention includes a first substrate having a transparent conductive layer and a plurality of row electrodes composed of bus electrodes formed in contact with the transparent conductive layer, and a dielectric layer formed so as to cover the row electrodes. A plurality of column electrodes and an insulator layer is formed so as to cover the column electrodes, a partition is formed between the column electrodes on the insulator layer, and a phosphor layer is formed between the partition walls A method of manufacturing a plasma display panel in which a formed second substrate is disposed oppositely and a discharge gas is filled between the first and second substrates, the dielectric layer and the insulating layer At least one of the first coating layer and the second coating layer formed on the first coating layer and coated in a coating direction having a predetermined angle with the coating direction of the first coating layer. A plasma display characterized by comprising It is a Reipaneru method of manufacturing.
[0018]
As a result, the dielectric layer or insulator layer has a two-layer structure in which the coating directions are formed at a predetermined angle with respect to each other, and the occurrence of streaky film thickness unevenness caused by uneven thickness of the dielectric layer or insulator layer is suppressed. The plasma display panel can be provided.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
[0020]
(Embodiment 1)
One embodiment of the plasma display panel of the present invention is shown in FIG. Basically, the configuration is almost the same as that of the conventional example shown in FIG. Although not clearly shown in FIG. 1, in the present invention, the dielectric layer 105 is composed of a first dielectric layer 105a and a second dielectric layer 105b, and these dielectric layers are formed at a predetermined angle. . The insulator layer 113 is also composed of at least a first insulator layer and a second insulator layer, and these insulating layers are formed not at the same direction but at a predetermined angle. Both the dielectric layer 105 and the insulator layer 113 may have a two-layer structure with a predetermined angle, but at least one of them may have a two-layer structure and be configured with a predetermined angle. Also good.
[0021]
Since the other components are almost the same as those in FIG. 6 showing the conventional example, detailed description thereof is omitted. The features of the present invention are illustrated by FIGS. An outline of the production process of the front plate 100 will be described with reference to FIG.
[0022]
FIG. 2A shows a manufacturing process of the front plate 100. In manufacturing the front plate 100, first, an indium-tin-oxide (ITO) film having a thickness of 0.2 μm is formed on a soda-lime glass substrate 101 having a thickness of about 3 mm using a vacuum film-forming apparatus such as sputtering. A film is deposited, and a plurality of pairs of transparent electrodes 102a and 103a are formed using a fine processing technique such as ion beam etching.
[0023]
Next, as shown in FIG. 2B, a black stripe 107 is formed between a pair of adjacent transparent electrodes 102a and 103a. The black stripe 107 has a paste-like photosensitive glass material containing a metal oxide black pigment as a main component, is printed and applied onto a glass substrate 101, and is exposed and developed using a photolithography technique after drying, thereby forming a predetermined pattern.
[0024]
Next, as shown in FIG. 2C, film thicknesses of 0.1 μm and 3 μm are respectively formed on the glass substrate 101 on which the transparent electrodes 102a and 103a and the black stripes 107 are formed using a vacuum film forming apparatus such as sputtering. , 0.1 μm Cr13, Cu14, and Cr15 are sequentially laminated to form respective films.
[0025]
Subsequently, as shown in FIG. 2D, a resist film made of a photosensitive resin is applied to the surface of Cr15, and the resist film is selectively irradiated with ultraviolet rays through a photomask, and developed to correspond to the bus electrodes 102b and 103b. A resist pattern 16 is formed at the position.
[0026]
Further, as shown in FIG. 2E, using the resist pattern 16 as a mask, a Cr etching solution made of a material such as cerium nitrate or ammonium nitrate and a Cu etching solution made of an aqueous solution of ferric chloride or cupric chloride. Are used to sequentially remove the exposed layers of Cr15, Cu14 and Cr13. Then, bus electrodes 102b and 103b having a three-layer structure of Cr13, Cu14 and Cr15 are formed in contact with the transparent electrodes 102a and 103a.
[0027]
Here, as a method of forming the bus electrodes 102b and 103b, it is also possible to use photosensitive silver and to form the bus electrodes 102b and 103b using a photolithography technique. Further printing using a silver paste thus may be formed selectively patterned.
[0028]
Next, after removing the resist pattern 16, as shown in FIG. 2 (f), one row electrode 104 is constituted by a pair of scan electrodes 102 and sustain electrodes 103, and between adjacent row electrodes 104. A glass substrate 101 having a black stripe 107 is obtained.
[0029]
Next, as shown in FIG. 3A, a glass substrate 101 is fixed on a stage (not shown) having high flatness by means such as vacuum suction, and a coating machine 30 similar to a slit coater is attached to the glass substrate. A glass resin 41 to be a first dielectric layer 105a is dropped and applied by scanning in the X direction parallel to one side of 101. The glass resin 41 used here is a glass resin made of a mixture of a glass powder mainly composed of highly transparent SiO ₂ , a binder resin and a diluent, and the coating thickness is approximately 80 μm. Further, the glass resin 41 is selectively formed only on the image display portion of the glass substrate 101.
[0030]
Next, as shown in FIG. 3B, the coating machine 30 is scanned in parallel with the other side Y of the glass substrate 101, and the glass resin 42 to be the second dielectric layer 105b is applied dropwise. The same material as the glass resin 41 is used as the glass resin 42, and the coating thickness is approximately 80 μm.
[0031]
In the two-layer glass resins 41 and 42 applied by such a method, the streaky film thickness spots 43 and 44 generated in the respective application processes have a structure orthogonal to each other, and uneven thickness due to interference between the two is dispersed. Will be alleviated.
[0032]
Subsequently, the glass substrate 101 is heat-treated in an inert gas having a temperature of 300 to 600 ° C. By the heat treatment step, the first dielectric layer 105a and the second dielectric layer 105b are formed by drying the solvent in the glass resins 41 and 42, thermal decomposition and gasification of the binder resin, and vitrification of the glass powder. Form. Furthermore, this process can enhance the insulation and transparency of the dielectric layers 105a and 105b.
[0033]
The combined thickness of the dielectric layers 105a and 105b after the heat treatment is about 40 μm.
[0034]
Subsequently, a protective layer 106 made of magnesium oxide (MgO) is formed on the surface of the dielectric layer 105 to obtain the front plate 100. Thereafter, the front plate 100 constructed through the above steps and the separately created back plate 110 are arranged to face each other, and are bonded together using a sealing agent such as frit glass to form a panel. Further, after degassing while heating the panel, a discharge gas composed of an inert gas containing xenon as a main component is sealed to manufacture the plasma display panel of the present invention.
[0035]
The first dielectric layer 105a and the second dielectric layer 105b are both formed of the same glass material 41, but it is not always necessary to use the same material. For example, materials having different electrical characteristics such as dielectric constant May be used, or materials having different chemical characteristics such as melting point may be used.
[0036]
As described above, according to the first embodiment of the present invention, the dielectric layer 105 is configured by the first dielectric layer 105a and the second dielectric layer 105b formed to be orthogonal to each other. As a result, it is possible to suppress the occurrence of streaky film thickness spots caused by uneven thickness of the dielectric layer 105.
[0037]
In forming the first dielectric layer 105a and the second dielectric layer 105b, a two-layer structure in which the coating directions are orthogonal to each other is used. However, these coating directions are not necessarily orthogonal to each other. There is no necessity. According to experiments, it has been clarified that the occurrence of streaky film thickness spots can be suppressed at an angle of 60 degrees or more.
[0038]
(Embodiment 2)
The second embodiment is the same as the first embodiment in that when the dielectric layer 105 is formed, the glass resin is applied at least twice. The difference from the first embodiment is that heat treatment is performed in an inert gas at a temperature of 200 to 400 ° C. after application of the glass resin for forming the first dielectric layer 105a.
[0039]
By this heat treatment, at least the solvent evaporates and the thermosetting proceeds and the fluidity is weakened or lost in the first layer glass resin. The inconvenience that the thickness fluctuates can be eliminated. In particular, the effect is remarkable in screen printing in which pressure is applied during application.
[0040]
In addition, the dielectric breakdown voltage of the dielectric layer 105 can be increased by applying a glass resin for forming the second dielectric layer 105b and then performing heat treatment in an inert gas at a temperature of 300 to 600 ° C.
[0041]
In the first embodiment and the second embodiment, the scan electrode 102 and the sustain electrode 103 are constituted by the transparent electrode 102a and the bus electrode 102b made of one metal layer. However, as shown in FIG. The present invention can also be applied to the case where the scan electrode 146 or the sustain electrode 147 having a structure in which the divided electrodes 141 to 144 are connected by the connection portion 145 is used. In addition, the present invention has an effect that generation of pinholes is suppressed even in the divided electrode structure.
[0042]
(Embodiment 3)
The third embodiment relates to the configuration and manufacturing method of the back plate 110. The configuration of the back plate 110 according to the third embodiment is basically the same as the conventional example shown in FIG. 4, but the configuration of the insulating layer 113 is different.
[0043]
That is, in the third embodiment, when the insulating layer 113 is formed, the glass resin is applied at least twice, and the application directions are orthogonal to each other.
[0044]
Hereinafter, the configuration of the back plate 110 according to the third exemplary embodiment will be described with reference to FIG. A column electrode 112 having a three-layer structure of Cr / Cu / Cr is formed on the surface of the glass substrate 111 serving as the back plate 110 by a method substantially similar to the method described in the first embodiment. As a method of forming the column electrode 112, a method using photosensitive silver and a photolithography technique, or a method of forming a pattern by printing a silver paste can be used.
[0045]
Next, in order to form the insulating layer 113 at a position corresponding to the image display portion of the glass substrate 111, glass resin is applied in two portions. The application method may be the same as the application method of the dielectric layer 105 described in the first embodiment. That is, the first insulating layer 113a scans the coating machine 30 parallel to one side X of the glass substrate 111, and the second insulating layer 113b scans the coating machine 30 parallel to the other side Y of the glass substrate 111. Apply resin.
[0046]
As a glass resin for forming the insulating layer 113, silica (SiO ₂ ) is a main component, and metal oxides such as alumina (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), zirconium oxide (ZrO) are added. This glass resin has the effect of increasing the reflectance. The coating thickness is 15 μm for both the first and second layers.
[0047]
Subsequently, the glass substrate 111 coated with the glass resin is heat-treated in an inert gas at a temperature of 300 to 600 ° C., drying of the solvent in the glass resin, thermal decomposition and gasification of the binder resin, and glass powder are made of glass. The insulating layer 113 having a thickness of about 10 μm is formed.
[0048]
Although both the first insulating layer 113a and the second insulating layer 113b are made of the same glass material, the same material is not necessarily used. For example, materials having different electrical characteristics such as dielectric constant may be used. Alternatively, materials having different chemical characteristics such as a melting point may be used.
[0049]
Thereafter, the back plate 110 is obtained by forming the phosphors 115 on the partition walls 114 and the inner walls of the partition walls 114. The back plate 110 created through the above steps and the separately created front plate 100 are arranged to face each other, and are bonded together using a sealing material such as frit glass to form a panel. And after performing a degassing process while heating, the discharge gas which consists of an inert gas which has xenon as a main component is enclosed, and the plasma display panel concerning Embodiment 3 of this invention is obtained.
[0050]
As described above, according to the third embodiment of the present invention, the insulating layer 113 is formed by forming the first insulating layer 113a and the second insulating layer 113b in directions orthogonal to each other. It is possible to suppress the occurrence of streaky film thickness spots caused by uneven thickness of 113.
[0051]
(Embodiment 4)
The fourth embodiment is the same as the third embodiment in that the glass resin is applied in two steps when the insulating layer 113 is formed. The difference from Embodiment 3 is that heat treatment is performed in an inert gas at a temperature of 200 to 400 ° C. after application of the glass resin for forming the first insulating layer 113a.
[0052]
As a result of the heat treatment, at least the solvent evaporates and the thermosetting proceeds and the fluidity is weakened or lost in the first glass resin, so the coating film thickness fluctuates when the second glass resin is applied. The inconvenience of doing can be eliminated. In particular, the effect is remarkable in screen printing in which pressure is applied during application.
[0053]
In addition, after the glass resin is applied to form the second insulating layer 113b, the withstand voltage of the insulating layer 113 can be increased by heat treatment in an inert gas at a temperature of 300 to 600 ° C.
[0054]
【The invention's effect】
As described above, in the plasma display panel manufacturing method of the present invention, the dielectric layer or the insulating layer includes a two-layer structure, and these layers are formed at a predetermined angle with each other. Generation of streaky film thickness unevenness caused by uneven thickness of the dielectric layer or the insulating layer can be suppressed, and the display image quality can be made uniform.
[0055]
Furthermore, if the electrical characteristics of the first layer and the second layer of the dielectric layer or insulator layer having a two-layer structure, for example, the dielectric constants are made different, the film thicknesses thereof can be further reduced.
[0056]
Furthermore, by changing the chemical characteristics of the first and second dielectric layers or dielectric layers having a two-layer structure, for example, by changing the softening point of the glass resin, improvement of the withstand voltage and suppression of pinhole generation are suppressed. be able to. Specifically, use of a glass resin with little reaction with the electrode material for the first glass resin improves the withstand voltage, or uses a glass resin with high paintability with the electrode material for the first glass resin. Therefore, it is possible to improve the withstand voltage by suppressing the generation of pinholes.
[0057]
In addition, according to the method for manufacturing a plasma display panel of the present invention, the design freedom is increased, the high quality design of the plasma display panel is facilitated, and the production yield is improved.
[Brief description of the drawings]
Process diagram showing the process of manufacturing the plasma display panel according to a perspective view and FIG. 2] the invention showing a main portion of a plasma display panel according to the invention, FIG 3 (a) is a plasma display according to the present invention FIG. 4B is a perspective view showing a process for producing a panel when an insulating layer is formed on the substrate of the plasma display panel according to the present invention. FIG. 4 shows scan electrodes suitable for the plasma display panel according to the present invention. FIG. 5 is a perspective view showing a state in which a glass resin (insulating layer) is formed on the substrate of the plasma display panel according to the present invention. FIG. 6 is a perspective view showing a conventional plasma display panel . Figure 7 is a cross-sectional view showing a main part of a conventional plasma display panel 8 dielectric coating according to the conventional plasma display panel manufacturing method Perspective view showing a method FIG. 9 is a cross-sectional view showing a film Atsumadara produced on a glass substrate at the time of dielectric coating of a conventional plasma display panel manufacturing method EXPLANATION OF REFERENCE NUMERALS
13,15 Cr
14 Cu
16 resist pattern 30 coating machine 31 slit 32, 41, 42 glass resin 33, 34, 35, 43, 44 film thickness unevenness 100 front plate 101, 111 glass substrate 102, 146 scan electrode 102a, 103a transparent electrode 102b, 103b bus electrode 103, 147 Sustain electrode 104 Row electrode 105 Dielectric layer 105a First dielectric layer 105b Second dielectric layer 106 Protective layer 107 Black stripe 110 Back plate 112 Column electrode 113 Insulator 114 Partition 115 Phosphor 120 Gap 141 142, 143, 144 Dividing electrode 145 connection part

Claims (2)

A first substrate having a plurality of row electrodes comprising a transparent conductive layer and bus electrodes formed in contact with the transparent conductive layer, and a dielectric layer formed so as to cover the row electrodes, and a plurality of columns An insulating layer is formed so as to cover the column electrode, and a partition is formed on the insulating layer between the column electrodes, and a phosphor layer is formed between the partitions. A method of manufacturing a plasma display panel, wherein a substrate is disposed opposite to each other, and a discharge gas is filled between the first and second substrates, wherein at least one of the dielectric layer and the insulator layer includes: A first coating layer and a second coating layer formed on the first coating layer and coated in a coating direction having a predetermined angle with the coating direction of the first coating layer. Of plasma display panels characterized by Law.   2. The method of manufacturing a plasma display panel according to claim 1, wherein the second coating layer is applied in a coating direction orthogonal to a coating direction of the first coating layer.

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