[Background Art] A PDP is a light-emitting device that projects images by exciting a fluorescent substance formed in a discharge cell. The PDP is lighter than a conventional cathode ray tube, and a process for manufacturing the plasma PDP is simple. Moreover, due to its simplicity in producing a slim and large screen, demands for the PDP are tending upward in use of a status bulletin board at the stock exchange, a display for videoconferences, and a wall mounted wide TV set.

Fig. 1 is a perspective view of a disassembled PDP, and Fig. 2 shows a structure where X and Y electrodes are-fetched to one direction in the PDP used for configuration of a multi-screen.

In the PDP, a front substrate 10 whereon X and Y electrodes are formed is sealed in parallel with a rear substrate 20 whereon an address electrode is formed.

On the front substrate 10, X and Y electrodes are formed for sustaining light emission of cells by inter-discharge in one pixel. The X and Y electrodes comprise transparent electrodes (or ITO electrodes) (Xa, Ya) formed of transparent ITO materials and bus electrodes (Xb, Yb) formed of metal materials.

The X and Y electrodes are covered by a dielectric layer 12 for restricting discharge current and insulating a space between electrode pairs. A protective layer 13 is formed on the dielectric layer.

On the rear substrate 20 are arranged in parallel barrier ribs 21 having a stripe type (or dot type) for forming a plurality of discharge spaces, that is cells C. The address electrode A is arranged in parallel with the barrier ribs 21, crossed with the electrodes X and Y. A dielectric layer 23 is formed on the address electrode A.

Furthermore, a R. G. B fluorescent layer 24 which radiates visible radiation in order to display images at address discharge is covered on the top of the rear substrate 20 except the top cross section of the barrier rib 21.

However, due to technical restraint or equipment limitation, the plasma display panel has been developed in the size 63 inches at largest to date.

The commercial display requires conditions to be wide, slim, and highly bright.

Therefore, the conventional 63 inch commercial display is too small in size matter, and needs for a larger size have been continuously desired.

In order to meet the requirements, a plurality of plasma display panels are arranged so that a multi screen device forms large screen. For this configuration, a PDP is used where X and Y electrodes are fetched to one direction. In case of arranging 4 PDPs for a large screen, as shown in Fig. 2, X and Y electrodes are fetched not to the edge of the PDPs contacting each other but to one direction, thereby closely connecting PDPs without any gap between the PDPs.

When X and Y electrodes are fetched to one direction for configuration of a multi-screen, the X and Y electrodes are fetched on the same electrode pad region/connection region, and an interval between the X and Y electrodes is reduced in half in comparison with the conventional case where X and Y electrodes are not fetched to one direction. For example, the number of lines increases from 480 lines to 960 lines in a conventional VGA class, thereby narrowing the space between the X and Y electrodes.

The interval reduction between the X and Y electrodes causes migration because metal ions in metal electrodes are diffused into adjacent electrodes by voltage application in a burning process or discharge, thereby degrading reliability of electrodes and affecting life span/quality of the panel.

[Brief Description of the Drawings] Fig. 1 is a perspective view of a disassembled plasma display panel.

Fig. 2 is a diagram showing an electrode structure of a PDP wherein X and Y electrodes are fetched to one direction for configuration of a multi-screen device.

Fig. 3 is a diagram showing an electrode structure of a front substrate of a PDP according to an embodiment of the present invention.

Figs. 4 to 7 are diagrams showing a process for fabricating a common pad according to an embodiment of the present invention.

[Detailed Description of the Invention] It is an object of the present invention to solve a migration problem by fetching X electrodes of X and Y electrodes, which are fetched to the same direction, as at least one or more common pads.

In order to achieve the above-described object, there is provided an AC-plasma display panel comprising a front substrate sealed with a rear substrate to form a superposition region including a display region, wherein each side of the front substrate and the rear substrate is extended in different directions to form an electrode pad region.

Here, the AC-plasma display panel comprises: a X electrode formed to be extended to a space between the electrode pad region and the display region; a Y electrode formed to be extended to the electrode pad; and at least one or more common pads connected in common to the X electrode and extended to the electrode pad. Here, the common pad is commonly connected to the X electrode through a contact hole of a dielectric layer located at a predetermined place on the X electrode.

Also, there is provided a method for fabricating an AC-plasma display panel comprising a X electrode and a Y electrode alternately arranged in parallel for sustaining discharge on a front substrate. The method comprises: the first process of forming a transparent electrode on a glass substrate; the second process of forming the X electrode and the Y electrode on the transparent electrode; the third process of coating the electrodes with a dielectric material to have a contact hole on a predetermined place of the X electrode; and the fourth process of forming at least one or more common pads to connect the X electrode in common by filling a metal material in the contact hole and fetching the common pad to an electrode pad region.

[Preferred Embodiments] Fig. 3 is a diagram showing an electrode structure of a front substrate of a PDP according to an embosimerstçof the present invention.

In an embodiment, the PDP comprising a plurality of PDPs interconnected is used for a large display device. For close adhesion of the PDPs, X and Y electrodes are fetched to one direction so that a pulse waveforms for sustaining discharge is applied.

However, the end portions of X electrodes for receiving a pulse are not fetched to electrode pads but connected in common to a common pad 34 at predetermined places 31-33 between an electrode pad region of a display region in the panel. The common pad 34 is fetched to the electrode pad region, thereby receiving a pulse to be applied to the X electrode.

Specifically, the extension of the X electrode is limited within a dielectric coating region 35 of a front substrate 30. On the dielectric layer of the predetermined places 31-33 outside of the display region of the panel among X electrodes is formed a via contact hole for electrically connecting the common pad 34 to the X electrode.

Figs. 4 to 7 are diagrams showing a process for fabricating the common pad 34 according to an embodiment of the present invention.

In an embodiment, the explanation on a rear substrate is omitted because it is the same as a conventional one. Instead, a process for fabricating the front substrate 30 whereon the common pad 34 is formed is only described.

As shown in Fig. 4, transparent electrodes 44 (ITO or NESA) are formed on a glass substrate 42.

Next, bus electrodes 46 for forming X and Y electrodes are formed on the paired transparent electrodes 44, as shown in Fig. 5.

A method for forming the bus electrodes 44 includes a print method, a photosensitive electrode method, and a Cr/Cu/Cr method in the second process. In the print method, electrode paste is printed by using a screen mask whereon a pattern is formed. In the photosensitive electrode method, after a photosensitive electrode material is printed on the whole surface of the substrate 42 whereon the transparent electrode 44 is formed, an exposure and development process is performed using a photo-mask. In the Cr/Cu/Cr method, after Cr, Cu and Cr are sequentially deposited on the substrate 42 where the transparent electrode 44 is formed, unnecessary portions are etched using a photo-mask to form electrodes.

Thereafter, as shown in Fig. 6, a dielectric layer 48 is formed by coating a dielectric material in order to secure insulation in discharge on the substrate whereon the transparent electrode 44 and the bus electrode 46 are formed. The dielectric layer 48 may be formed as a single layer or multiple layers. Also, the dielectric layer 48 may be formed using materials that can inhibit reaction with the bus electrodes 46 in a burning process and improve a working voltage and transmittivity and smoothness of the surface.

Via contact holes 482 and 484 are formed at predetermined places 31-33 of the X electrode of the bus electrode 46 in the dielectric layer 48. The predetermined places 31-33 are to be connected to the common pad 34 between the electrode pad region and the display region in the panel.

For the configuration of the via contact holes, in formation of the dielectric layer 48, the print process is performed using a screen mask or a dielectric layer sheet whereon holes are formed at the corresponding places 31-33.

As shown in Fig. 7, the common pad 34 for commonly connecting the X electrodes is formed by filling a metal material in the contact holes 482 and 484 using a print or dispensing method. The common pad 34 is formed by using metal materials having a broader width than that of the X electrode and having low resistance such as Ag.

One end of the common pad 34 is fetched to the same direction as that of the Y electrode, that is the electrode pad region. As a result, a pulse to be applied to the X electrode is applied to each X electrode through the common pad 34.

In the above-described embodiment, after all X electrodes are commonly connected to one common pad 34, one common pad 34 is fetched to the electrode pad region. However, the present invention is not limited to the particular forms disclosed.

For example, a predetermined number of X electrodes as a FPC unit is connected to one common pad 34, and then fetched to an electrode pad region, respectively.

[Industrial Applicability]

As discussed earlier, in an embodiment of the present invention, partial electrodes are not directly fetched to an electrode pad region but commonly connected to a common pad in a PDP. As a result, the migration between electrodes due to interval reduction between electrodes in the electrode pad region can be prevented, thereby improving life span and quality of products.