JP2010015819A - Method of manufacturing substrate structure for plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a substrate structure for PDP, which can suppress bubbles due to a reaction between an electrode and a glass material layer. <P>SOLUTION: The method of manufacturing the substrate structure for PDP comprises a step in which a glass material layer that contains the glass material is so formed as to cover an electrode on a substrate where the electrode is formed, and the glass material layer is baked to form a dielectric layer. In the course of baking, the electrode is grounded, or, if the electrode consists of a transparent electrode and a metal electrode formed thereon, a voltage is applied between the transparent electrode and the metal electrode. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a substrate structure for a plasma display panel (hereinafter referred to as “PDP”).

  FIG. 7 is an exploded perspective view showing an example of the structure of a conventional PDP. This PDP has a front side substrate structure 1 and a back side substrate structure 2.

  In the front side substrate structure 1, a plurality of display electrodes 3 are arranged on the glass substrate 1a. The display electrode 3 includes a transparent electrode 3a and a metal electrode 3b, respectively. The display electrode 3 is covered with a dielectric layer 4. The dielectric layer 4 is covered with a protective film 5.

  In the back side substrate structure 2, address electrodes 6 extending in a direction substantially perpendicular to the display electrodes 3 are disposed on the glass substrate 2a. The address electrode 6 is covered with a dielectric layer 9. Partitions 7 are arranged on both sides of the address electrode 6 to divide cells in the column direction. Further, a phosphor layer 8 is formed by applying phosphors that generate red (R), green (G), and blue (B) visible light on the dielectric layer 9 and on the side surfaces of the partition walls 7 by being excited by ultraviolet rays. Is formed. The address electrode 6 may be disposed in the dielectric layer 4 of the front substrate structure 1 so as to intersect the display electrode 3.

  With the front side substrate assembly 1 and the rear side substrate assembly 2 facing each other so that the protective film 5 and the partition wall 7 are in contact with each other, the peripheral portion is sealed with a sealing member to form a discharge space inside the discharge space. After evacuating, a discharge gas such as Ne—Xe is sealed in the discharge space to produce a PDP.

  In this PDP, display is performed by repeated discharge between the two display electrodes 3 forming a pair.

  In an example, the dielectric layers 4 and 6 covering the metal electrode 3b or the address electrode 6 are formed by forming a glass material layer so as to cover the metal electrode 3b or the address electrode 6 and firing the glass material layer. For the glass material layer, a glass paste containing glass frit, a binder and a solvent is applied on the substrate, and then the solvent is dried (paste method), or a glass sheet containing glass frit and a binder is pasted on the substrate (sheet method). ). The glass frit is made of lead glass, for example.

  When the dielectric layer is formed by the above method, bubbles may be generated during the firing due to a reaction at the interface between the electrode and the glass material layer. This bubble is usually removed by the glass flowing.

  By the way, glass frit made of lead-free glass may be used as a material for the dielectric layer. Since lead-free glass generally has a high softening point, it is difficult to remove bubbles due to glass flow, and bubbles may remain in the dielectric layer even after firing. The bubble residue in the dielectric causes a problem of insulation failure starting from the panel, and the yield rate is greatly reduced. If it is a front substrate structure, the bubble residue reduces the light transmittance. Reduce display brightness.

  This invention is made | formed in view of such a situation, and provides the manufacturing method of the board | substrate structure for PDP which can suppress generation | occurrence | production of the bubble by reaction with an electrode and a glass material layer.

Means for Solving the Problems and Effects of the Invention

  In the method for manufacturing a substrate structure for a PDP according to the present invention, a dielectric material layer is formed by forming a glass material layer containing a glass material on a substrate on which an electrode is formed so as to cover the electrode, and firing the glass material layer. A step of forming and grounding the electrode during the firing, or applying a voltage between the transparent electrode and the metal electrode when the electrode is composed of a transparent electrode and a metal electrode thereon. Features.

The present inventor came to the idea that the movement of electrons between the electrode and the glass material layer is related to the generation of bubbles while earnestly examining the cause of generation of bubbles. And when the electrode was grounded at the time of baking, it has confirmed that generation | occurrence | production of a bubble was suppressed. Moreover, when a voltage was applied between the transparent electrode and the metal electrode during firing, it was confirmed that the generation of bubbles was suppressed when the potential of either the transparent electrode or the metal electrode was increased. Furthermore, when a voltage was applied such that the potential of the metal electrode was higher than the potential of the transparent electrode, it was found that the generation of bubbles was particularly suppressed. The present inventor completed the present invention based on the above findings. Although the principle that the generation of bubbles is suppressed by the present invention is not necessarily clear, it is presumed that this is because the movement of electrons between the electrode and the glass material layer is suppressed.
According to the present invention, since the generation of bubbles is suppressed, the substrate structure for PDP can be manufactured at a high yield rate even when a glass material made of lead-free glass having no environmental load is used.
Hereinafter, various embodiments of the present invention will be exemplified.

The voltage may be applied so that the metal electrode side is positive.
The firing is performed by fixing the substrate to a surface plate with a clamp electrically connected to the electrode and moving the surface plate in a firing apparatus with the clamp grounded, or the transparent electrode The substrate is fixed to the surface plate with a pair of clamps electrically connected to each of the metal electrodes, and the surface plate is moved in the baking apparatus with a voltage applied between the pair of clamps. You may go by.
The various embodiments shown here can be combined with each other.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The contents shown in the drawings and the following description are examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

1. Method for Manufacturing PDP Substrate Structure A method for manufacturing a PDP substrate structure according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1A to FIG. 1D are cross-sectional views showing the manufacturing process of the PDP substrate structure of the present embodiment. Here, description will be given by taking as an example a case where the electrode is the display electrode 3 including the transparent electrode 3a and the metal electrode 3b. The following description is basically applicable to the case where the electrode is the display electrode 3 including only the metal electrode 3b and the case where the electrode is an address electrode.

  The manufacturing method of the substrate structure for PDP of this embodiment forms the display electrode 3 which consists of the transparent electrode 3a and the metal electrode 3b on it on the board | substrate 1a, and contains the glass material so that the display electrode 3 may be covered. Forming the dielectric layer 4 by firing the glass material layer 15 and forming the layer 15, and grounding the display electrode 3 during the firing or applying a voltage between the transparent electrode 3a and the metal electrode 3b. Is applied.

1-1. Display Electrode Process First, as shown in FIG. 1A, a display electrode 3 including a transparent electrode 3a and a metal electrode 3b thereon is formed on a substrate 1a.

The kind of board | substrate 1a is not specifically limited, The board | substrate 1a consists of transparent substrates, such as a glass substrate, for example. The transparent electrode 3a can be formed by patterning a transparent electrode material film made of ITO, SnO ₂ , ZnO or the like into a transparent electrode shape.

  The material and configuration of the metal electrode 3b are not particularly limited, and the metal electrode 3b is made of a single layer of Ag, Au, Al, Cu, Cr, or a stacked body thereof (for example, a stacked structure of Cr / Cu / Cr). . In one example, the metal electrode 3b has a stacked structure of an adhesion layer 11a, a Cu layer 11b, and a coating layer 11c. In this case, the metal electrode 3b is formed by forming a laminated film composed of the material film of the adhesion layer 11a, the material film of the Cu layer 11b, and the material film of the covering layer 11c on the transparent electrode 1a, and patterning the laminated film into a metal electrode shape. Can be formed. The composition of the adhesion layer 11a is not particularly limited as long as it can improve the adhesion between the Cu layer 11b and the substrate 1a. In one example, the adhesion layer 11a is made of Cr. The Cu layer 11b is a layer made of Cu, but may contain a small amount of another component. The composition of the coating layer 11c is not particularly limited as long as it can prevent oxidation of the Cu layer 11b, but is made of Cr in one example. The material film of the adhesion layer 11a, the material film of the Cu layer 11b, and the material film of the coating layer 11c can be formed by sputtering or vapor deposition, respectively. The adhesion layer 11a can be omitted if unnecessary.

The shapes of the transparent electrode 3a and the metal electrode 3b are not particularly limited, and may be a T shape or a ladder shape. The shapes of the transparent electrode 3a and the metal electrode 3b may be the same or different from each other. For example, the transparent electrode 3a may be T-shaped or ladder-shaped, and the metal electrode 3b may be straight. The display electrode 3 is comprised by the transparent electrode 3a and the metal electrode 3b. At least one end of the metal electrode 3b is led out to the periphery of the substrate and used as an electrode terminal.
Two display electrodes 3 are paired to form a display line. As an electrode arrangement form, an arrangement in which a non-discharge region (also referred to as a reverse slit) is provided between electrode pairs, and electrodes are arranged at equal intervals. The adjacent electrodes are arranged by any one of the ALIS type arrangements in which the discharge regions are all formed between the adjacent electrodes. This pair includes a scan electrode used for address discharge with the address electrode and a sustain electrode used for sustain discharge with the scan electrode.

1-2. Next, as shown in FIG. 1B, a glass material layer 15 containing a glass material is formed so as to cover the display electrode 3.

  The glass material layer 15 only needs to contain a glass material and become the dielectric layer 4 by firing. The “glass material” is a material made of glass, for example, a glass frit. For the glass material layer 15, for example, a glass paste containing a glass frit, a binder, and a solvent is applied on the substrate, and then the solvent is dried (paste method), or a glass sheet containing the glass frit and the binder is pasted on the substrate. (Sheet method).

The composition of the glass material is not particularly limited, and may be made of lead glass or lead-free glass. From the viewpoint of environmental load, lead-free glass is preferable. The glass material preferably contains 10 mol% or more of alkali glass. In this case, there is an advantage that crystallization of glass is likely to occur. Moreover, it is preferable that a glass material contains 30 mol% or less of alkali glasses. When the content of the alkali glass is too large, the moisture resistance is not sufficient, or the glass becomes unstable which is likely to cause phase separation inside. Alkali glass means glass made of an oxide of an alkali metal such as Na ₂ O, K ₂ O or Li ₂ O. The content of the alkali glass is, for example, 10 to 30 mol%, specifically, for example, 10, 15, 20, 25, 30 mol%. The content of alkali glass may be within a range between any two of the numerical values shown here. The glass material is preferably made of alkali zinc borosilicate glass. This is because this glass is a lead-free glass but has a relatively low crystallization temperature.

  Although the softening point of a glass material is not specifically limited, For example, it is 450-600 degreeC.

  Although the glass crystallization temperature of a glass material is not specifically limited, It is preferable that it is 650 degrees C or less. This is because crystallization of the glass material is likely to occur in this case. The glass crystallization temperature can be determined from the temperature of a peak showing an exothermic reaction when changing from glass to crystal in differential thermal analysis (DTA). The glass crystallization temperature of the glass material is, for example, 500 ° C. to 650 ° C., and specifically, for example, 500, 550, 600, or 650 ° C. The glass crystallization temperature of the glass material may be within a range between any two of the numerical values shown here, or may be any one or less. Note that the glass crystallization temperature of the glass material is usually higher than the softening point of the glass material.

1-3. Next, as shown in FIG. 1C, the dielectric material layer 4 is formed by firing the glass material layer 15. During the firing, the display electrode 3 is grounded or a voltage is applied between the transparent electrode 3a and the metal electrode 3b. Thereby, generation | occurrence | production of a bubble can be suppressed.

  The display electrode 3 may be grounded by either grounding the transparent electrode 3a, grounding the metal electrode 3b, or grounding both the transparent electrode 3a and the metal electrode 3b, but by grounding the metal electrode 3b. Preferably, it is more preferable to carry out by grounding both the transparent electrode 3a and the metal electrode 3b. This is because in such a case, generation of bubbles can be effectively suppressed.

  The method of firing while the display electrode 3 is grounded is not particularly limited. For example, as shown in FIGS. 2A and 2B, the display electrode 3 (at least one of the transparent electrode 3a and the metal electrode 3b). The substrate 1a is fixed to the surface plate 19 with a clamp 17 electrically connected to the surface plate 19 and the surface plate 19 is moved in the direction of arrow X in FIG. It can be carried out. The display electrode 3 is grounded, for example, by bringing the conductive belt 21 and the clamp 17 wound around a plurality of rollers 23 arranged in the traveling direction of the surface plate 19 into contact with each other and grounding the conductive belt 21. Can do. In this case, when the clamp 17 moves in the direction of the arrow X together with the surface plate 19, the conductive belt 21 in contact with the clamp 17 rotates. Accordingly, it is possible to smoothly move the clamp 17 in a state where the contact between the clamp 17 and the conductive belt 21 is maintained. The surface plate 19 can be moved on the transport roller 25.

  Regarding the voltage application, the voltage may be applied so that the metal electrode 3b side is positive (+) (so that the potential of the metal electrode 3b is higher than the potential of the transparent electrode 3a). Although voltage may be applied so that the electrode 3a side is positive, the former has a greater effect of suppressing bubble generation. Although the voltage to apply is not specifically limited, For example, it is about 0.5-5V. Specifically, this voltage is, for example, 0.5, 1, 1.5, 2, 3, 4, 5V. This voltage may be within a range between any two of the numerical values exemplified here. Further, the voltage to be applied may be set so that the magnitude of the flowing current becomes a predetermined value. The magnitude of the current per electrode is, for example, 0.005 to 5 μA, specifically, for example, 0.005, 0.01, 0.05, 0.1, 0.2, 0.3, 0. .4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 3, 4, 5 μA. The magnitude of this current may be within a range between any two of the numerical values exemplified here.

  The method of firing in a state where a voltage is applied is not particularly limited. For example, as shown in FIGS. 2 (a) and 2 (b), a pair electrically connected to each of the transparent electrode 3a and the metal electrode 3b. The substrate 1a is fixed to the surface plate 19 with the clamp 17 and the surface plate 19 is moved in the direction of arrow X in FIG. Do. The voltage is applied by, for example, bringing the conductive belt 21 wound around the plurality of rollers 23 arranged in the traveling direction of the surface plate 19 and the clamp 17 into contact with each other and contacting each of the pair of the clamps 17. Can be performed by applying a voltage between the two. In this case, when the clamp 17 moves in the direction of the arrow X together with the surface plate 19, the conductive belt 21 in contact with the clamp 17 rotates. Accordingly, it is possible to smoothly move the clamp 17 in a state where the contact between the clamp 17 and the conductive belt 21 is maintained. The surface plate 19 can be moved on the transport roller 25.

  The firing temperature of the glass material layer 15 is not particularly limited as long as the dielectric layer 4 can be formed. The firing profile of the glass material layer 15 is not particularly limited, but in one example, as shown in FIG. 3, a temperature rising period in which the firing temperature is raised, a temperature stable period in which the firing temperature is constant, and a cooling period in which the firing temperature is lowered. It is preferable to set so as to have. The cooling may be forced cooling or natural cooling. Moreover, the firing temperature in the temperature stabilization period is not particularly limited, but is, for example, about 600 to 640 ° C.

1-4. Next, as shown in FIG. 1D, a protective film 5 is formed on the dielectric layer 4 to complete the manufacture of the PDP substrate structure of this embodiment.

  The protective film 5 is made of a metal (more specifically, a divalent metal) oxide such as magnesium oxide, calcium oxide, strontium oxide, or barium oxide, and is preferably made of magnesium oxide. The protective film 5 is formed by vapor deposition, sputtering, coating, or the like.

2. Manufacturing method of PDP Rear side substrate assembly comprising front side substrate assembly 1 manufactured by the method of the above embodiment, address electrode 6, dielectric layer 9, partition wall 7 and phosphor layer 8 on substrate 2a. A panel having an airtight discharge space is obtained by bonding the peripheral edge with a sealing material with the two facing each other, and after discharging the discharge space of the panel, a discharge gas (for example, PDP can be manufactured by encapsulating neon mixed with about several percent xenon).

  Various features shown in the above embodiments can be combined with each other. In the case where a plurality of features are included in one embodiment, one or a plurality of features can be appropriately extracted and used alone or in combination in the present invention.

3. Effect demonstration experiment Hereinafter, the experiment which shows the relationship between the earthing | grounding of an electrode or the voltage application between electrodes, and bubble generation | occurrence | production is demonstrated.

3-1. Production of Experimental Substrate First, a transparent electrode 3a made of ITO and a metal electrode 3b having a three-layer structure of Cr / Cu / Cr were formed on a glass substrate 1a. Next, a glass material layer 15 was formed by applying a glass paste so as to cover these electrodes. Next, the glass material layer 15 is fired in a state where the transparent electrode 3a or the metal electrode 3b is grounded, a voltage is applied between the transparent electrode 3a and the metal electrode 3b, or a voltage is applied to both ends of the metal electrode 3b. Thus, the dielectric layer 4 was formed.

  The transparent electrode 3a and the metal electrode 3b were formed in the shapes shown in FIGS. 4 (a) and 4 (b). The width of the transparent electrode 3a is 365 μm, the width of the metal electrode 3b is 75 μm, and the distance between the transparent electrodes is 120 μm. As the glass paste, a borosilicate glass frit, an acrylic / cellulose resin binder, and terpineol (solvent) was used. The thickness of the glass material layer 15 was 10 μm.

  Grounding or voltage application during firing was performed by wiring as shown in FIGS. The applied voltage during firing was 1.5 V, and the current was 1 μA (0.05 μA per electrode).

  As shown in FIG. 6, the baking is performed by heating the hot plate 27 in a state where the surface plate 19 is placed on the hot plate 27 and the substrate 1 a after the glass material layer 15 is formed on the platen 19. (Wiring for grounding or voltage application is not shown in FIG. 6). The firing profile is as shown in FIG. The firing temperature was measured by placing a temperature sensor on the glass substrate 1a. The firing temperature in the temperature stabilization period was 620 ° C. During the cooling period, heating of the hot plate 27 was stopped and the plate was naturally cooled at room temperature.

3-2. Measurement of the number of bubbles A dark field photograph of the experimental substrate produced by the above method was taken, and the number of bubbles generated at the edge of the metal electrode 3b was counted. When counting the number of bubbles, only those having a size of 3 μm or more were counted. The shooting conditions of the dark field photograph are as shown in Table 1.

  The obtained results are shown in Table 2.

Referring to Table 2, the following can be understood.
(1) Generation of bubbles could be suppressed regardless of which of the transparent electrode 3a and the metal electrode 3b was grounded. Moreover, when the metal electrode 3b was grounded, generation | occurrence | production of a bubble was able to be suppressed more strongly.
(2) The generation of bubbles could be suppressed by applying a voltage between the transparent electrode 3a and the metal electrode 3b. Although the generation of bubbles could be suppressed when either the transparent electrode 3a or the metal electrode 3b was made positive (+), the generation of bubbles was more strongly suppressed when the metal electrode 3b side was made positive. I was able to.
(3) When voltage was applied to both ends of the metal electrode 3b, the number of bubbles generated slightly increased.
From the above, it can be demonstrated that the generation of bubbles can be suppressed by grounding at least one of the transparent electrode 3a and the metal electrode 3b during firing, or by applying a voltage between the transparent electrode 3a and the metal electrode 3b. It was.

1A to 1D are cross-sectional views showing a manufacturing process of a PDP substrate assembly according to an embodiment of the present invention. 2 (a) and 2 (b) illustrate a method of firing in a process of manufacturing a substrate structure for a PDP according to an embodiment of the present invention while electrodes are grounded or a voltage is applied between the electrodes. It is the perspective view and front view for this. The baking profile in the baking process in the manufacturing process of the board | substrate structure for PDP of one Embodiment of this invention is shown. FIG. 4A is a plan view showing the shapes of the transparent electrode and the metal electrode in the effect verification experiment of the present invention, and FIG. 4B is a cross-sectional view taken along the line II in FIG. is there. FIGS. 5A to 5D are plan views showing a wiring method when the electrodes are grounded or a voltage is applied between the electrodes during firing in the effect verification experiment of the present invention. It is sectional drawing corresponding to FIG.4 (b) for demonstrating the baking method in the effect verification experiment of this invention. It is a disassembled perspective view which shows an example of the conventional PDP structure.

Explanation of symbols

1: Front side substrate structure 1a: Front side substrate 2: Back side substrate structure 2a: Back side substrate 3: Display electrode 3a: Transparent electrode 3b: Metal electrode 4: Dielectric layer 4a: First dielectric layer 4b: Second Dielectric layer 5: Protective layer 6: Address electrode 7: Partition 8: Phosphor layer 9: Dielectric layer 11a: Adhesion layer 11b: Cu layer 11c: Cover layer 13: Exposed portion 15: Glass material layer 17: Clamp 19: Surface plate 21: Conductive belt 23: Roller 25: Transport roller 27: Hot plate

Claims (3)

Forming a glass material layer containing a glass material on the substrate on which the electrode is formed so as to cover the electrode, and baking the glass material layer to form a dielectric layer;
A plasma display panel, wherein the electrode is grounded during the firing, or a voltage is applied between the transparent electrode and the metal electrode when the electrode is composed of a transparent electrode and a metal electrode thereon. Of manufacturing a substrate structure for a vehicle. The method of manufacturing a substrate structure for a plasma display panel according to claim 1, wherein the voltage is applied so that the metal electrode side is positive. The firing is performed by fixing the substrate to a surface plate with a clamp electrically connected to the electrode and moving the surface plate in a firing apparatus with the clamp grounded, or the transparent electrode The substrate is fixed to the surface plate with a pair of clamps electrically connected to each of the metal electrodes, and the surface plate is moved in the baking apparatus with a voltage applied between the pair of clamps. The manufacturing method of the board | substrate structure for plasma display panels of Claim 1 or 2 performed by these.

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