KR100444517B1 - METHOD OF FABRICATING ElECTRODE IN PLASMA DISPLAY PANEL - Google Patents

Abstract

The present invention relates to a method for manufacturing an electrode of a plasma display panel, in which the thickness of the electrode is uniform and the adhesion between the substrate and the electrode is increased.

According to an embodiment of the present invention, a method of manufacturing an electrode of a plasma display panel includes forming a seed layer in a display area of a substrate, forming a dummy electrode detachably on a non-display area of the substrate, and plating the substrate. And forming an electrode pattern on the seed layer, and removing the dummy electrode.

Description

Electrode manufacturing method of plasma display panel {METHOD OF FABRICATING ElECTRODE IN PLASMA DISPLAY PANEL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a plasma display panel, and more particularly, to a method for manufacturing an electrode of a plasma display panel in which the thickness of the electrode is uniform and the adhesion between the substrate and the electrode is increased.

Recently, researches on plasma display panels (hereinafter, referred to as "PDPs"), which are advantageous for large size, have been actively conducted. PDPs usually display images by using a gas discharge phenomenon, and are largely classified into a direct current (DC) driving type and an alternating current (AC) driving type. AC-driven PDPs have the advantages of low power consumption and long life compared to direct current.

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP is formed on a scan / sustain electrode 30Y and a common sustain electrode 30Z formed on an upper substrate 10, and a lower substrate 18. An address electrode 20X is provided. Each of the scan / sustain electrode 30Y and the common sustain electrode 30Z has a line width smaller than the line widths of the transparent electrodes 12Y and 12Z and the transparent electrodes 12Y and 12Z, and is formed on one edge of the transparent electrode. (13Y, 13Z). The transparent electrodes 12Y and 12Z are usually formed on the upper substrate 10 by indium tin oxide (ITO). The metal bus electrodes 13Y and 13Z are usually formed of metals such as chromium (Cr) and formed on the transparent electrodes 12Y and 12Z to reduce voltage drop caused by the transparent electrodes 12Y and 12Z having high resistance. The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan / sustain electrode 30Y and the common sustain electrode 30Z side by side. In the upper dielectric layer 14, wall charges generated during plasma discharge are accumulated. The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used. The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode 20X is formed, and the phosphor layer 26 is coated on the surfaces of the lower dielectric layer 22 and the partition wall 24. The address electrode 20X is formed in the direction crossing the scan / sustain electrode 30Y and the common sustain electrode 30Z. The partition wall 24 is formed in parallel with the address electrode 20X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. An inert mixed gas such as He + Xe, Ne + Xe, He + Xe + Ne is injected into the discharge space provided between the upper and lower substrates 10 and 18 and the partition wall 24.

The metal bus electrodes 13Y and 13Z and the address electrodes 20X of the sustain electrode pairs 30Y and 30Z are also referred to as the FODEL method, a sputtering method or a dry screen method, which is a sputtering method or a screen print method. Is formed on the substrate (10, 18).

In the photo method, a photosensitive silver paste is printed on the entire surface of a substrate, an exposure / development process is performed on the silver paste, and then a predetermined process is performed to form an electrode pattern. This photo method has the advantage of easy process and high electrode pattern formation, but has a problem of shrinking the electrode pattern by a certain process involving high heat treatment due to high loss of silver paste. .

In the sputtering method, a desired metal film is deposited by sputtering on a substrate, and then subjected to photoresist coating, exposure, and developing processes, and finally an etching process is performed to form an electrode pattern. This sputtering method has a disadvantage in that it takes a long process time and a high manufacturing cost to form an electrode pattern with a thickness of several μm.

Screen printing method repeats the process of aligning the screen on the substrate, applying and drying the metal paste until the height of the metal paste reaches the desired height. In the screen printing method, when the metal paste reaches a desired height, the metal paste is predetermined to form an electrode on the substrate. This screen printing method has the advantages of simple process and low manufacturing cost. However, since the screen alignment, the application and drying of metal paste must be repeated when printing every metal paste, the process time is long and the electrode pattern is misaligned. There is a disadvantage that the shape precision of the falling.

Recently, the plating method has been used to form the metal electrode of the PDP.

In the plating method, after forming a conductive seed layer on a substrate, a photoresist is formed thereon, and then a photoresist pattern is formed through an exposure / development process to expose the seed layer along an electrode pattern having a desired shape. Subsequently, in the plating method, electroplating is performed on the substrate on which the seed layer and the photoresist pattern are formed to grow metal on the seed layer by a desired height to form an electrode pattern. This plating method is relatively easy to process and has the advantage of high definition of the electrode pattern and small waste of materials. However, the thickness of the electrode pattern becomes uneven and the adhesion between the electrode material and the substrate is poor in the electroplating process. There is this. This will be described in detail with reference to FIG. 2.

Referring to FIG. 2, in the plating method, electroplating is performed by depositing a substrate 32 of a PDP on which a seed layer and a photoresist pattern are formed, in a plating bath 40 in which a source electrode 38 is installed and a plating solution 36 is placed. Is carried out in a state. When the electroplating starts as the voltage is applied, an electric field 34 is applied between the source electrode 38 and the seed layer of the substrate 32 and the metal ions emitted from the source electrode 38 accumulate on the seed layer and seed. The metal grows on the layer. At this time, the side region 32a of the substrate 32 has a higher concentration of the electric field 34 and an overcurrent than the other substrate portions, resulting in a higher height of the metal layer grown on the seed layer, which is generated by field concentration and overcurrent. Due to the stress of the metal layer, the adhesion between the metal layer and the substrate is inferior. Further, the concentration of the electric field in the side region 32a of the substrate 32 is because the fresh plating solution 36 is supplied to the side region 32a of the substrate 32 faster than the other substrate portions. This is also caused by the relatively small concentration polarization phenomenon of the side edge region 32a of ().

Accordingly, it is an object of the present invention to provide a method for manufacturing an electrode of a PDP which makes the thickness of the electrode uniform and increases the adhesion between the substrate and the electrode.

1 is a perspective view showing a conventional three-electrode AC surface discharge type plasma display panel.

2A to 2C are cross-sectional views showing a conventional electrode manufacturing method step by step.

3A through 3E are cross-sectional views illustrating a method of manufacturing an electrode of a plasma display panel according to a first embodiment of the present invention.

4A through 4D are cross-sectional views illustrating a method of manufacturing an electrode of a plasma display panel according to a second exemplary embodiment of the present invention.

5 is a plan view illustrating a dummy electrode or a dummy pad formed on a substrate in the method of manufacturing a plasma display panel according to an exemplary embodiment of the present invention.

6 is a cross-sectional view showing that the dummy tape is attached in the process of Figure 3b.

7 is a cross-sectional view showing that the dummy tape is attached in the process of Figure 4b.

8 is a cross-sectional view illustrating a plating process performed in a plating bath in the method of manufacturing a plasma display panel according to an embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

10,18,32,51,61: substrate 12Y, 12Z: transparent electrode

13Y, 13Z: metal bus electrode 14, 22: dielectric layer

16: protective film 20X: address electrode

24: partition 26: phosphor

30Y: scan / sustain electrode 30Z: common sustain electrode

32a, 82a: side area 34,84: electric field

36,86 plating solution 38,88 source electrode

40,80 plating bath 52,62 seed layer

53,63 photoresist 54 metal electrode pattern

71: effective electrode pattern 72: dummy electrode pattern

73: dummy pad 74: conductive tape, conductive plate material

In order to achieve the above object, the electrode manufacturing method of the PDP according to the present invention comprises the steps of forming a seed layer in the display area of the substrate, the step of forming a dummy electrode detachably on the non-display area of the substrate, Forming an electrode pattern on the seed layer by plating the substrate; and removing the dummy electrode.

The dummy electrode may be formed at upper and lower sides or left and right edges of the substrate.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 3A to 8.

Referring to FIG. 3A, a method of manufacturing an electrode of a PDP according to a first embodiment of the present invention may include a substrate (eg, sputtering, E-Beam plating, or the like) using a dry deposition method or an electroless plating method. 51, the seed layer 52 is formed of a multilayer metal of any one or at least one of Cr, Ti, Zn, Ni, and Cu. In addition, the seed layer 52 may be formed of a conductive oxide or nitride. The substrate 51 is an upper substrate of a PDP on which a metal bus electrode is formed or a lower substrate of a PDP on which an address electrode is formed.

On the substrate 51 on which the seed layer 52 is formed, after the photoresist, for example, the photoresist 53 is applied, the mask is aligned and the photoresist 53 is patterned through an exposure / development process. Then, the seed layer 52 is exposed as shown in FIG. 3B through the photoresist pattern in a desired electrode pattern shape.

Subsequently, in the method of manufacturing the electrode of the PDP according to the first embodiment of the present invention, electroplating or electroless plating is performed as shown in FIG. 3C to grow metal on the seed layer by a desired thickness. As described below in the plating process, a conductive dummy electrode or a dummy pad is formed in the side region of the substrate where the electric field is concentrated, in addition to the effective electrode, thereby making the thickness of the effective electrode uniform and preventing a decrease in adhesion between the substrate and the metal.

As a result of the plating process, a metal electrode pattern 54 having a predetermined thickness is formed on the seed layer 52 as shown in FIG. 3D. Finally, the seed layer 52 of the remaining portion except for the seed layer 52 under the metal electrode pattern 54 is removed through an etching process so as not to cause a short circuit between the electrodes.

4A to 4D illustrate a method of manufacturing an electrode of a PDP according to a second embodiment of the present invention.

Referring to FIG. 4A, a method of manufacturing an electrode of a PDP according to a second embodiment of the present invention is Cr, Ti, Zn on a substrate 61 using a dry deposition method such as sputtering, two-beam plating, or an electroless plating method. The seed layer 62 is formed of a multilayer metal of any one, or at least one of Ni, Cu, and the like. In addition, the seed layer 62 may be formed of a conductive oxide or nitride. The substrate 61 is an upper substrate of a PDP on which a metal bus electrode is formed or a lower substrate of a PDP on which an address electrode is formed.

On the substrate 61 on which the seed layer 62 is formed, after the photoresist, for example, the photoresist 63 is applied, the mask is aligned thereon, and the photoresist 63 is patterned as shown in FIG. 4B through an exposure / development process. do.

Subsequently, in the method of manufacturing the electrode of the PDP according to the second embodiment of the present invention, the seed layer 62 exposed on the substrate 61 is removed by performing an etching process as shown in FIG. 4C. Then, only the seed layer 62 under the photoresist pattern 63 remains in the seed layer 62 formed on the substrate 61. After the seed layer pattern 62 is formed, electroplating or electroless plating is performed. Then, metal is grown on the seed layer 62, and when metal is grown by a desired electrode thickness as shown in FIG. 4D, plating is stopped. As described below in the plating process, a conductive dummy electrode or a dummy pad is formed in the side region of the substrate where the electric field is concentrated, in addition to the effective electrode, thereby making the thickness of the effective electrode uniform and preventing a decrease in adhesion between the substrate and the metal.

In order to uniformize the thickness of the effective electrode in the plating process and to prevent a decrease in adhesion between the substrate and the metal, the electrode manufacturing method of the PDP according to the embodiment of the present invention includes a substrate 51 in which an electric field is concentrated in the plating process as shown in FIG. The dummy electrode pattern 72 and / or the dummy pad 73 are formed in the upper / lower side or the left / right side edge region 61. The dummy electrode pattern 72 and the dummy pad 73 are disposed above and below the screen display area in which the effective electrode pattern 71 is formed, and unlike the effective electrode pattern 71 for generating a discharge when the PDP is driven, plating is performed. In the process, the electric field is induced to concentrate itself so that the electric field is not concentrated on the effective electrode pattern 71 positioned at the edge. Accordingly, an electric field is uniformly applied to the effective electrode patterns 71 during the plating process by the dummy electrode pattern 72 and the dummy pad 73. The number of dummy electrode patterns 72 and the area of the dummy pad 73 may be adjusted according to the size of the substrates 51 and 61 or the state of the plating bath.

In order to form the dummy electrode pattern 72 and the dummy pad 73, a mask for exposing the seed layer corresponding to the dummy electrode pattern and the dummy pad in addition to the effective electrode pattern is manufactured. This mask is aligned on the substrates 51 and 61 to which the photoresists 53 and 63 are applied, as shown in Figs. 3B and 4B. Next, through the exposure / development process, the dummy electrode pattern 72 and the dummy pad 73 are formed on the substrates 51 and 61 at the same time as the effective electrode 71. In this case, the dummy electrode pattern 72 and the dummy pad 73 remain on the substrates 51 and 61 even after the previous process is completed.

The method for removing the dummy electrode pattern 72 and the dummy pad 73 on the substrates 51 and 61 is as follows. A mask for exposing only the seed layer corresponding to the effective electrode pattern 71 is manufactured. This mask is aligned on the substrates 51 and 61 to which the photoresists 53 and 63 are applied, as shown in Figs. 3B and 4B. In this state, only the seed layer corresponding to the effective electrode pattern 71 is exposed through the exposure / development process. Subsequently, a conductive tape or a conductive plate material serving as the dummy electrode pattern 72 and the dummy pad 73 is attached to the seed layer of the effective electrode pattern 71 or on the photoresist, and is electrically connected to the seed layer. After electroplating with the conductive tape or plate attached, the conductive tape or plate is removed together with the photoresist pattern and unnecessary seed layer removed in a later process. No conductive plate remains. In other words, in the photoresist pattern forming process of FIG. 3B, the conductive tape or the conductive plate material 74 is attached onto the photoresist pattern 53 removed in a later process as shown in FIG. 6, and the conductive tape or conductive plate material 74 is attached. ) Is electrically connected to the seed layer 52, and plating is performed. When the photoresist pattern 74 is removed in a later step, the conductive tape or the conductive plate material 74 is simultaneously removed. Similarly, in the process of FIG. 4B, as shown in FIG. 7, the conductive tape or the conductive plate material 74 is attached onto the seed layer 62 to be removed in a later process, and plating is performed. When the seed layer is removed in a later step, the conductive tape or the conductive plate 74 is removed at the same time.

8 shows the electric field distribution applied to the substrate in the plating process in the electrode manufacturing method of the PDP according to the embodiment of the present invention.

Referring to FIG. 8, a seed layer corresponding to the effective electrode pattern 71 is formed in the display area of the substrate 82 in the plating bath 80 in which the plating solution 86 is contained. A seed layer corresponding to the dummy electrode pattern 72 and / or the dummy pad 73 is formed in the side region 82a. When plating starts in this state, an electric field is applied between the source electrode 88 and the seed layer of the substrate 82 and the metal ions emitted from the source electrode 88 accumulate on the seed layer and the metal grows on the seed layer. Done. At this time, in the side region area 82a of the substrate 82 on which the dummy electrode pattern 72 and / or the dummy pad 73 are formed, the electric field 84 concentrates and the overcurrent flows compared to other substrate portions, but the effective electrode The electric field 84 is uniformly applied to the display area where the patterns 71 are formed, and the same current flows. As a result, after completion of the plating process, the effective electrode patterns 71 of the entire display area are uniform in thickness and uniformly maintained at a high level of adhesion with the substrate.

As described above, the electrode manufacturing method of the PDP according to the present invention by forming a dummy electrode pattern or a dummy pad in the area where the electric field is concentrated in the plating process to uniform the thickness of the electrode patterns existing in the entire display area during the plating process. The adhesion between the substrate and the electrode can be evenly increased.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (4)

Forming a seed layer in the display area of the substrate; Forming a dummy electrode detachably on a non-display area of the substrate; Forming an electrode pattern on the seed layer by plating the substrate; And removing the dummy electrode. The method of claim 1, The dummy electrode is formed on the upper, lower, left and right edges of the substrate electrode manufacturing method of the plasma display panel. delete delete