JP3560417B2 - Method for manufacturing plasma display panel - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a PDP (Plasma Display Panel).
[0002]
PDPs are attracting attention as high-definition color display devices because they are capable of high-speed large-screen display. Technologies for increasing the productivity of PDPs are important in meeting the demand for lower prices in the market.
[0003]
[Prior art]
A PDP is a self-luminous display panel in which a pair of substrates (usually a glass plate) are opposed to each other with a minute gap therebetween, and a discharge space is formed inside by sealing the periphery. Generally, in a matrix display type PDP, a large number of electrodes extending in a row direction are provided on one substrate, and a large number of electrodes extending in a column direction are provided on the other substrate. In each board, each electrode is led out to the edge of the board, and each end is locally enlarged as an external connection terminal. External connection terminals are arranged along the electrode arrangement direction at the edge of each substrate, and these external connection terminals are electrically connected to an external drive circuit via a flexible wiring board. In order to enable a group of external connection terminals to be crimped to the flexible wiring board, the size of each substrate is selected so that the edge where the external connection terminals are arranged protrudes outside the other substrate.
[0004]
2. Description of the Related Art Conventionally, a panel structure having projections (partitions) made of an insulating material between each external connection terminal is known (JP-A-5-217509). According to this structure, the flexible wiring board is properly positioned, and a short circuit between the terminals is prevented. That is, when there is no protrusion between the external connection terminals adjacent to each other, if the position of the flexible wiring board is shifted in the direction in which the external connection terminals are arranged at the time of crimping of the flexible wiring board, the conductor on the wiring board side becomes adjacent to the two adjacent connection terminals. Contact with both of the external connection terminals causes a short circuit between the terminals.
[0005]
[Problems to be solved by the invention]
As the display becomes higher definition, the arrangement pitch of the external connection terminals becomes smaller and the distance between the terminals becomes shorter. Since the lower limit of the pattern width by the screen printing method is about 50 μm, a technique of patterning an insulating layer having a uniform thickness by photolithography must be used to form the above-described short-circuit prevention projection. However, if an insulating layer is specially provided to prevent a short circuit between terminals, the number of man-hours for manufacturing a PDP is increased by that amount, resulting in an increase in cost.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to reduce the number of special steps for providing a projection for preventing a short circuit between terminals as much as possible and to increase productivity.
[0009]
[Means for Solving the Problems]
The method according to claim 1 , wherein an electrode pattern including external connection terminals arranged in one direction, an insulator layer covering a portion of the electrode pattern in a display area, and a short circuit between adjacent external connection terminals are prevented. A method for manufacturing a plasma display panel having projections for forming, on a substrate on which the electrode pattern is formed, a layer including the insulator layer, the display region and a terminal forming region outside the display region. Forming an insulating material layer extending over the insulating material layer; forming a mask layer corresponding to the arrangement pattern of the protrusions on the insulating material layer by pattern exposure of a photosensitive material; Forming a projection by removing an exposed portion outside the display region.
[0010]
Since the protrusion is formed by patterning the insulator layer covering the electrode pattern, it is not necessary to provide a special insulating material layer to form the protrusion.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is an exploded perspective view showing the internal structure of the PDP 1 according to the first embodiment.
The PDP 1 is an AC-driven surface discharge type PDP. On the inner surface of the glass substrate 11 on the front side, a pair of sustain electrodes X and Y are arranged for each matrix display line. The sustain electrodes X and Y each include a transparent conductive film 41 and a metal film 42, and are covered with a dielectric layer 17 for AC driving. A protective film 18 made of magnesium oxide (MgO) is deposited on the surface of the dielectric layer 17.
[0012]
On the other hand, an address electrode A, partition walls 29, and a phosphor layer 28 for color display are provided on the inner surface of the glass substrate 21 on the back side. Each address electrode A corresponds to one column of the matrix display. The shape of each partition wall 29 in plan view is linear. These partition walls 29 divide the discharge space 30 into sub-pixels EU in the line direction of the matrix display, and the gap size of the discharge space 30 is defined to a constant value. One pixel (pixel) EG of the display includes three sub-pixels EU arranged in the line direction. In the PDP 1, since the arrangement pattern of the partition walls 29 is a so-called stripe pattern, a portion corresponding to each column in the discharge space 30 is continuous in the column direction across all the lines. The emission colors of the sub-pixels EU in each column are the same.
[0013]
The pixel EG is substantially square, and the sub-pixel EU is a rectangle long in the column direction. For this reason, the arrangement pitch of the address electrodes A is inevitably smaller than the arrangement pitch of the sustain electrodes X and Y, and a short circuit between the terminals of the address electrodes A is likely to occur. In other words, for the sustain electrodes X and Y, it is possible to secure a sufficiently large inter-terminal distance in order to prevent a short circuit. Therefore, in the PDP 1, it is necessary to particularly consider the short circuit between the terminals of the address electrode A.
[0014]
FIG. 2 is a perspective view showing a terminal structure of the address electrode A, and FIG. 3 is a sectional view showing a state where the address electrode A is connected to an external conductor.
In FIG. 2, each address electrode A is led out to the edge of the glass substrate 21 and is formed integrally with the external connection terminal Aa. The external connection terminals Aa are arranged at equal intervals, and wall-shaped projections 51 are provided between the external connection terminals Aa to prevent a short circuit.
[0015]
When the PDP 1 is used, a flexible wiring board 90 is crimped to the glass substrate 21 as shown in FIG. Terminals 92 are provided on the flexible wiring board 90 at the same pitch as the external connection terminals Aa. When the flexible wiring board 90 and the glass substrate 21 are overlapped, the terminal 92 is positioned by the protrusion 51 and comes into contact with the external connection terminal Aa. The height of the protrusion 51 is set to a value (for example, 30 μm) slightly smaller than the sum of the thickness of the external connection terminal Aa (for example, 2 μm) and the thickness of the terminal 92 (for example, 30 μm).
[0016]
In the PDP 1 having the above-described configuration, predetermined components are separately provided for each of the glass substrates 11 and 21 to produce a front panel and a rear panel. And a series of steps for filling the discharge gas. Hereinafter, a method of manufacturing a rear panel including a process unique to the present invention will be described.
[0017]
FIG. 4 is a schematic view of the manufacturing method according to the first embodiment.
First, an electrode pattern PA including a large number of address electrodes A having external connection terminals Aa is formed on a glass substrate 21 by patterning a metal thin film (FIG. 4A). In the illustrated example, each address electrode A is alternately distributed to one end and the other end in the column direction of the glass substrate 21 one by one, and the external connection terminals Aa are dispersedly arranged on both sides in the column direction. .
[0018]
Next, a glass paste is applied to almost the entire surface of the glass substrate 21 and dried to form a paste layer 290 extending over the display region E1 and the terminal formation region EAa outside the display region E1. At this time, the paste layer is expected to shrink in the subsequent baking, so that the thickness after baking corresponds to the height of the partition wall 29 in the display region E1 and corresponds to the height of the protrusion 51 in the terminal formation region EAa. The thickness of each part of the 290 is selected (FIG. 4B). The paste layers 290 having different thicknesses depending on such portions can be easily formed by overlapping printing using two screen masks having different opening sizes.
[0019]
On the paste layer 290 in a dry state, for example, a dry film-shaped resist is attached by using a laminator, and the mask layer 63 and the protrusion 51 in a plan view shape corresponding to the partition wall 29 are formed by photolithography for performing pattern exposure and development. (FIG. 4C and FIG. 4D).
[0020]
Subsequently, the exposed portions of the paste layer 290 are removed by sand blasting to form paste layers 29s and 51s having a predetermined shape (FIG. 4E). Then, the paste layers 29 s and 51 s are fired at a time to form the partition walls 29 and the projections 51 at the same time. Thereafter, phosphors of three colors are sequentially applied one by one to complete the rear panel.
[0021]
FIG. 5 is a diagram illustrating the structure of the PDP 2 according to the second embodiment. In the figure, components having the same functions as those of the components of the PDP 1 of FIGS. 1 and 2 are denoted by the same reference numerals.
[0022]
The basic configuration of PDP2 is the same as PDP1 described above. The structural differences between the PDP 2 and the PDP 1 are that the address electrodes A are covered with an insulator layer (dielectric) 24 as shown in FIG. 5A, and the external connection terminals Aa of each address electrode A are different. The point is that a projection 52 made of the same material as the insulator layer 24 is provided between them.
[0023]
The protrusion 52 is a structure for preventing a short circuit between the terminals, and its height is slightly larger than the sum of the thickness of the external connection terminal Aa (for example, 2 μm) and the thickness of the terminal of the flexible wiring board (not shown) (for example, 30 μm). A small value (for example, 30 μm) is selected.
[0024]
FIG. 6 is a schematic view of the manufacturing method according to the second embodiment.
First, an electrode pattern PA including a predetermined number of address electrodes A having external connection terminals Aa is formed on a glass substrate 21 by patterning a metal thin film (FIG. 6A). In the illustrated example, each address electrode A is alternately distributed to one end and the other end in the column direction of the glass substrate 21 one by one, and the external connection terminals Aa are dispersedly arranged on both sides in the column direction. .
[0025]
Next, a glass paste is applied to almost the entire surface of the glass substrate 21 and baked to form a glass layer 240 extending over the display region E1 and the terminal formation region EAa outside the display region E1. At this time, shrinkage due to baking is expected, and the thickness after baking corresponds to the thickness of the insulator layer 24 (for example, 10 μm) in the display region E1, and corresponds to the height of the protrusion 52 in the terminal formation region EAa. Then, the thickness of each part of the glass layer 240 is selected (FIG. 6B). That is, the glass layer 240 is a layer including the insulator layer 24. The glass layers 240 having different thicknesses depending on such portions can be easily formed by overlapping printing of a glass paste using two screen masks having different opening patterns.
[0026]
The partition wall 29 is formed on the glass layer 240 (FIGS. 6C and 6D). The procedure of formation is as follows. [1] A glass paste is uniformly applied and dried. [2] A mask layer having a predetermined pattern is provided by photolithography. [3] Pattern the paste layer by sandblasting. [4] The paste layer after patterning is fired.
[0027]
After the partition walls 29 are formed, an acid-resistant resist is applied on the glass layer 240, and pattern exposure is performed to provide a mask layer 65 having a plan view shape corresponding to the projections 52 (FIG. 6E). Then, one end and the other end of the glass substrate 21 in the column direction are sequentially immersed in an etching solution such as a nitric acid solution to remove unnecessary portions of the glass layer 240 to form the projections 52 (FIG. 6). (F)]. Thereafter, phosphors of three colors are sequentially applied one by one to complete the rear panel.
[0028]
When the glass layer 240 is used as a layer for preventing the oxidation of the address electrode A in the manufacturing stage, the phosphor layer 28 is provided following the formation of the mask layer 65 before the etching of the glass layer 240. The sealing of the pair of glass substrates 11 and 21 has been completed. By using a heat-resistant resist as a material of the mask layer 65, deterioration of the mask layer 65 due to heat treatment at the time of sealing can be avoided. After the sealing, the projections 52 are formed by partially etching the glass layer 240. When the address electrode A is made of a material such as aluminum which is hardly oxidized, there is no problem even if the substrate is sealed after the projections 52 are formed as described above.
[0029]
In the first and second embodiments described above, the example in which the protrusions 51 and 52 are provided between the external connection terminals Aa of the address electrode A has been described. It may be provided. In that case, the process can be shared for the dielectric layer 17 and the projection.
[0030]
【The invention's effect】
According to the first aspect of the present invention, a special process for providing a projection for preventing a short circuit between terminals can be reduced as much as possible, and PDP productivity can be increased.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an internal structure of a PDP according to a first embodiment.
FIG. 2 is a perspective view showing a terminal structure of an address electrode.
FIG. 3 is a cross-sectional view showing a state where an address electrode and an external conductor are connected.
FIG. 4 is a schematic view of the manufacturing method according to the first embodiment.
FIG. 5 is a diagram illustrating a structure of a PDP 2 according to a second embodiment.
FIG. 6 is a schematic view of a manufacturing method according to a second embodiment.
[Explanation of symbols]
1,2 PDP (plasma display panel)
29 Partition wall 24 Insulator layers 51, 52 Projections 63, 64 Mask layer 65 Mask layer 240 Glass layer (insulating material layer)
290 Paste layer (insulating material layer)
Aa External connection terminal E1 Display area EAa Terminal formation area PA Electrode pattern

Claims (1)

A plasma display having an electrode pattern including external connection terminals arranged in one direction, an insulator layer covering a portion of the electrode pattern in a display area, and a protrusion for preventing a short circuit between adjacent external connection terminals. A method of manufacturing a panel,
Forming an insulating material layer on the substrate on which the electrode pattern is formed, the insulating material layer including the insulator layer and extending over the display region and a terminal formation region outside the display region.
Forming a mask layer corresponding to the arrangement pattern of the protrusions by pattern exposure of a photosensitive material on the insulating material layer,
Removing the exposed portion of the insulating material layer outside the display region to form the protrusion.

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