GB2410611A - Plasma display panel - Google Patents

Abstract

A plate for a plasma display panel comprising front and back plate members 50, 70. First electrodes are positioned on the back plate 50 and second and third electrodes positioned on the transparent front plate 70. A barrier wall 53 positioned between the front and back plates providing a discharge space for the plasma. Dielectric layers 52, 74 cover both sets of electrodes on respective plates, and a black matrix is formed between each pair of second and third electrodes. The matrix and the first or second and third electrodes are formed of a dielectric component and a conductive component. In one embodiment, the amounts of the dielectric and conductive components change in the thickness direction of the electrodes and matrix.

Description

PLATE FOR PLASMA DISPLAY PANEL (PDP), METHOD FOR FABRICATING THE PLATE,

AND PDP HAVING THE PANEL The present invention relates to a plasma display panel (PDP), and more particularly, to a plate for a PDP on which discharging electrodes are formed, a method for fabricating the plate, and a PDP adopting the plate.

Plasma displays generate a desired visual image by exciting a predetermined phosphor pattern with ultraviolet (UV) light generated by plasma discharge between two substrates in which plasma gas is sealed.

Such plasma displays are generally classified into DC type and the AC types according to the corresponding driving voltage, i.e., discharging mechanism. AC type PDPs are further classified into two types: one is a double substrate two electrode type and the other is a surface discharge type.

For the DC type PDP, the electrodes are exposed to a discharge space and charges directly migrate between facing electrodes. For the AC type PDP, electrodes are covered with a dielectric layer. Plasma discharge is caused by the electric field of wall charges instead of direct charge migration.

As an example, a surface discharging type PDP is shown in FIG. 1.

Referring to FIG. 1, the PDP comprises a structure including a pair of substrates, a back plate 10 and a front plate 16. The back plate 10 comprises a series of first electrodes 11 arranged in a predetermined pattern, a dielectric layer 12 covering the first electrodes 11, and barrier balls 13 formed on the dielectric layer 12 to keep a discharge gap and prevent electrical and optical crosstalk between cells. A 2s fluorescent layer 19 is formed on at least one side of the discharge gap partitioned by the barrier walls. The front plate 16 comprises transparent second third electrodes 14 and 15, and bus electrodes 14a and 15a, which are narrow and arranged on the transparent second and third electrodes 14 and 15, respectively, to reduce line resistance of the transparent second and third electrodes 14 and 15.

The front plate 16 further comprises a black matrix 20 formed between each pair of the transparent and third electrodes 14 and 15 to enhance the contrast of the image, a dielectric layer 17, and a protective layer covering all electrodes 14,15,14a, and 15a and the black matrix 20.

In a conventional PDP disclosed in Japanese Laid-open Patent Publication No. hei 8-315735, as shown in FIG. 2, surface discharging electrodes 30a and 30b arranged on at least one side of a surface discharging electrode region 30 are partially and linearly divided in the longitudinal direction, and the divided surface discharging electrodes 30a and 30b are electrically connected by a plurality of electrode portions 31. A black matrix 34 is formed between each pair of electrodes 30a and 30b.

Another conventional PDP disclosed in Japanese Laid-open Patent Publication No. hei 9-129137, as shown in FIG. 3, includes a plurality of row electrodes 40, which extend parallel to each other in the horizontal direction and are arranged with a discharge gap 41 therebetween, and a plurality of column electrodes 1 42 extending from adjacent row electrodes 40, with a separation gap therebetween and facing each other to form a light-emitting pixel region 44. There is also a light-emitting pixel region 43 with a narrower discharge gap than the light-emitting pixel region 44. A black matrix 46 is formed between each pair of the row electrodes 40 facing each other.

As described above, in the conventional surface discharge AC type PDP, the electrodes arranged on the front plate 16 include the bus electrodes 14a and 15a formed of silver (Ag) paste and transparent second and third electrodes 14 and 15 formed of indium tin oxide (ITO), or has a structure divided in the longitudinal direction using Ag paste. Also, the black matrixes 20, 34, and 46 arranged between s each pair of electrodes, which are paired to cause a discharge of plasma therebetween, are formed of a mixture of a black pigment and an insulating material.

To manufacture an optimal front plate capable of maximizing the function of a PDP, as described above, the electrodes and black matrix should be formed of appropriate materials, i.e., materials having different physical properties. For this reason, there is a need for separate patterning processes for the electrodes and the black matrix. However, separate patterning processes would complicate the overall manufacturing process.

For example, to manufacture the front plate 16, which includes the bus electrodes 14a and 15a, as shown in FIG. 1, and the second and third electrodes 14 and 15 formed as ITO electrodes, a bare front plate is cleaned, and an ITO layer is deposited on the front plate 16 by sputtering and then patterned into the second and third electrodes 14 and 15 for discharging, as shown in FIG. 4. For this patterning process, a positive photoresist is deposited on the ITO layer, and exposed and etched using a predetermined mask pattern. After the ITO electrodes are formed, a to bus electrode is printed on each of the ITO electrodes using Ag paste, dried, and sintered so that bus electrodes 14 and 15 are completely formed. After the formation of the bus electrodes 14a and 15a is completed, a black matrix 20 is printed using a mixture of a black pigment and an insulating material.

In the front plate manufacturing method described above, since the electrodes s and black matrix are formed through separate processes, the number of working steps increases and failure is more likely to occur, thereby lowering productivity. In particular, in the case where the electrodes of the front plate are exclusively formed of metal, there are problems in that external light is reflected due to low external-light absorbency, and the black matrix cannot be formed as fine patterns.

In a first aspect of the present invention, there is provided a plate for a plasma display panel (PDP), the plate comprising: a plate member formed of a transparent material; a series of electrodes formed in a predetermined pattern on the plate member; and a dielectric layer formed on the plate member to cover the electrodes, :s wherein the electrodes are formed of a dielectric first component and a second component of at least one selected from the group consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt). It is preferable that the plate of a POP further comprises a black matrix pattern formed between each of the electrodes.

Accordingly, the invention provides a plate for a plasma display panel (PDP), in which electrodes and a black matrix have good adhesiveness with respect to a plate member and improved mechanical characteristics due to the absence of internal stress.

In a second aspect of the present invention, there is provided a method for fabricating a plate for a plasma display panel (PDP), comprising: preparing a transparent plate member; depositing into a single deposition boat a mixture of 3-50% SiO by weight as a dielectric material and 50-97% by weight of at least one metal selected from the group consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt), wherein the dielectric material and metal have different melting points; loading the plate member into a vacuum chamber, and depositing the SiO and metal on the plate member while gradually raising the temperature of the deposition boat; patterning the resultant structure into electrodes and a black matrix pattern by photolithography; and forming a dielectric layer on the plate member on which the electrodes and the black matrix pattern are formed.

The present invention thus provides a method for fabricating a plate for a PDP, in which electrodes and a black matrix can be formed through simple processes so that productivity is improved.

In a third aspect of the present invention, there is provided a plasma display panel (PDP) comprising: a back plate; first electrodes formed in a predetermined pattern on the back plate; a transparent front plate bonded with the back plate having the first electrodes to form a discharge space therebetween; second and third s electrodes formed on one side of the front plate facing the first electrodes at a predetermined angle with respect to the first electrodes; a barrier wall for partitioning the discharge space between the back plate and front plate; a first dielectric layer formed on the back plate to cover the first electrodes; a second dielectric layer formed on the front plate to cover the second and third electrodes; and a black matrix pattern formed between each pair of the second and third electrodes on the one side of the front plate, wherein the black matrix pattern and either the first electrodes or the second and third electrodes are formed of a dielectric material and a conductive metal, and the amounts of the dielectric material and conductive metal change in the thickness direction of the electrodes and black matrix pattern.

The present invention thus provides a PDP with enhanced brightness and contrast characteristics by employing a plate on which electrodes and a black matrix are formed.

In one embodiment, there is provided a PDP comprising: a back plate; a transparent front plate bonded with the back plate with a predetermined separation to gap to form a discharge space therebetween; first and second electrodes arranged on a side of at least one of the back plate and front plate for causing a discharge of plasma; and a discharge gas with which the discharge space is filled, wherein the first and second electrodes are formed of a dielectric first component and a metallic second component of at least one selected from the group consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt).

In another embodiment, there is provided a PDP comprising: a back plate; first electrodes formed in a predetermined pattern on the back plate; a transparent front plate bonded with the back plate having the first electrodes to form a discharge space therebetween; second and third electrodes formed on one side of the front plate facing the first electrodes at a predetermined angle with respect to the first electrodes; a barrier wall for partitioning the discharge space between the back plate and front plate; a first dielectric layer formed on the back plate to cover the first electrodes; a second dielectric layer formed on the front plate to cover the second and third electrodes; and a black matrix pattern formed between each pair of the second and third electrodes on the one side of the front plate, wherein the black matrix pattern and either the first electrodes or the second and third electrodes are formed of a dielectric first component and a metallic second component of at least one selected from the group consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt).

In the present invention, the first component described above may comprise at least one dielectric material selected from the group consisting of SiOx, MgF2, CaF2, A12 03, SnO2, In2O3, and ITO, where x>1.

The above objects and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the to attached drawings in which: FIG. 1 is an exploded perspective view of an example of a conventional plasma display panel (PDP); FIGS. 2 and 3 are plan views of conventional PDPs showing the arrangement of second and third electrodes and bus electrodes; s FIG. 4 is a flowchart illustrating a conventional method of forming electrodes and a black matrix for a front panel; FIG. 5 is an exploded perspective view of a PDP according to the present invention; FIGS. 6 and 7 are plan views of the arrangement of second and third so electrodes for a plate of the PDP according to the present invention; and FIGS. 8 through 11 show changes in the concentrations of first and second components in the thickness direction of electrodes and a black matrix.

A plasma display panel according to the present invention, which is formed by Q binding a back plate and a front plate with a discharge space filled with a discharge gas therebetween, creates images by exciting phosphor with ultraviolet (UV) rays generated through the discharge of plasma by electrode pairs located in the discharge space. Such PDPs are classified into various types according to the number of electrodes, the arrangement of electrodes, the discharge site, or the type of applied voltage. A preferred embodiment of a POP according to the present invention is shown in FIG. 5.

Referring to FIG. 5, a plurality of first electrodes 51 are formed in a stripe pattern on a back plate 50 with a predetermined separation gap therebetween. A first dielectric layer 52 is formed on the back plate 50 to fill the first electrodes 51.

Barrier walls 53 having a predetermined height are formed in lines and parallel to the first electrodes 51 with a predetermined separation gap therebetween. The shape of the barrier walls 53 is not limited to lines, and may be formed as a lattice. Red (R), green (G), and blue (B) phosphors are alternately deposited between the barrier to walls 53 to form a fluorescent layer 60. Here, the arrangement of R. G. and B phosphors in the fluorescent layer 60 is not limited to this arrangement, and any arrangement which allows the formation of a color image can be applied.

The back plate 50 having the barrier walls 53 is combined with a front plate 70 to seal each discharge space partitioned by the barrier walls 53. Second and third s electrodes 71 and 72 are arranged on the inner surface of the front plate 70, which faces the barrier walls 53 of the back plate 50, in a predetermined pattern and perpendicular to the first electrodes 51. The second and third electrodes 71 and 72 are alternately arranged and each pair of second and third electrodes 71 and 72 is located in one pixel region. As shown in FIG. 6, the second and third electrodes 71 and 72 include parallel main electrode parts 71 b and 72b, and connect electrode parts 71 c and 72c perpendicular to the corresponding main electrode parts 71 b and 72b. Accordingly, the second and third electrodes 71 and 72 have apertures 71a and 72a, which are rectangular, respectively. It is preferable that the apertures 71a and 72a of each pair of the second and third electrodes 71 and 72 are arranged in 2 each light-emitting discharge space. However, the arrangement of the apertures 71a and 71a in a discharge space is not limited to this arrangement and can be appropriately modified within the scope of the present invention. It is also appreciated that the second and third electrodes 71 and 72 may be modified into various forms. For example, the second and third electrodes 71 and 72 may be So formed as indium thin oxide (ITO) electrodes, which need bus electrodes along the same. Alternatively, the second and third electrodes 71 and 72 may be formed of parallel metal electrodes and auxiliary electrodes formed of ITO extending from each of the parallel metal electrodes and facing each other. As shown in FIG. 7, second and third electrodes 71' and 72' may include parallel main electrodes parts 71'b and 72'b having a narrow width and connect electrode parts 71'c and 72,c, which connect the parallel main electrode parts 71'b and 72'b, respectively.

A black matrix pattern 80 for enhancing brightness and contrast of a display image is formed between each pair of the second and third electrodes 71 and 72. A second dielectric layer 74 and a protective layer 75 of magnesium oxide (MgO) are to formed to cover the second and third electrodes 71 and 72 and the black matrix pattern 80 of the front plate 70.

The second and third electrodes 71 (71) and 72 (72') and the black matrix pattern 80 are formed of a dielectric (first) component, and a metallic (second) component. The second component is at least one selected from the group 1s consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr) , tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt). The first component includes at least one dielectric material selected from the group consisting of SiOx (where x>1), MgF2, CaF2, A12 03, SnO2, In2O3, and ITO.

The concentrations of the first and second components vary for the second and third electrodes 71 and 72 and the black matrix pattern 80. The concentration of the dielectric component gradually decreases from an external light entering side toward the inner side of the front plate 70 adjacent to the back plate 50 or has a step gradient distribution, and the metallic component gradually increases toward the 2s inner side of the front plate 70. The amounts of the dielectric and metallic components are almost the same in the middle of each of the second and third electrodes 71 and 72 and the black matrix pattern 80.

According to the present invention, either the second and third electrodes 71 and 72 and the black matrix pattern 80 or the second and third electrodes 71 and 72 serving also as the black matrix pattern 80 are formed by slowly depositing dielectric material and metal to have reciprocal concentration profiles, as shown in FIGS. 8 and 9. Thus, a layered structure is not formed, and external light is absorbed, rather than reflected, at the interface between the black matrix pattern 80 and a plate member through which the external light enters the front plate 79, due to changes in the refractivity of the black matrix pattern 80 caused by variations in the concentrations of the dielectric and metallic components.

For the second and third electrodes 71 and 72 and the black matrix pattern 80 described above, a plate member 70N of the front plate 70, which is formed of siO2, has an index of refraction of about 1.5, which is almost the same as that of the to dielectric material forming a portion of the black matrix pattern adjacent to the plate member. Accordingly, external light is transmitted, rather than reflected, at the interface between the plate member 70N and the black matrix pattern, the index of refraction of the black matrix pattern is gradually increased and transmittance is decreased toward the inner side of the front plate 70 due to the gradient of the concentration profile of the black matrix pattern. Thus, almost all external light is absorbed, rather than reflected, by the black matrix pattern.

Meanwhile, the second and third electrodes 71 and 72 having the concentration profile of the first and second components described above absorb some of the visible light generated by excitation of the fluorescent layer so that the so opening ratio of the discharge space drops. However, since the second and third electrodes 71 and 72 for a front plate 70 according to the present invention are formed to have a mesh-type structure or are formed as transparent electrodes having bus electrodes thereon which are narrow, a decrease in brightness caused by a sudden drop of the opening ratio is prevented. In particular, for the second and third electrodes 71 and 72 having the concentration profile described above, the concentration of the dielectric (first) component gradually decreases and that of the metallic (second) component gradually increases with increased distance from the external light entering side of the front plate. As a result, the surfaces of the second and third electrodes 71 and 72 facing the discharge space exclusively contain the metal component to a predetermined depth so that conductivity is improved with a sheet resistance of o.1Qln or less. Thus, the second and third electrodes 71 and 72 for a plate according to the present invention satisfy requirements for the discharging electrodes of PDPs.

The front plate 70 for a POP which has either second and third electrodes 71 and 71 and a black matrix pattern 80 or second and third electrodes 71 and 72 serving also as the black matrix pattern 80 having the non-uniform composition described above can be manufactured through the following processes.

A plate member for the front plate 70 is cleaned and is loaded into and fixed in a vacuum chamber, facing a deposition boat. Next, a mixture of a dielectric material and metal having different melting points, i.e., the first and second components, is put into the deposition boat. Here, the mixture of the dielectric material and metal includes 50-97% the second component by weight, which is at least one metal selected from the group consisting of Fe, Co, V, Ti, Al, Ag, Si, Ge, Y. Zn, Zr, W. Ta, Cu. and Pt. and 3-50% the first component by weight, which is at least one dielectric material selected from the group consisting of SiOx (where x>1) , MgF2, CaF2, Al2 03, SnO2, in2O3, and ITO.

Next, vacuum thermal deposition is performed by varying the temperature of the deposition boat in which the mixture of the metal and dielectric material are contained. Here, the temperature of the deposition boat is varied by gradually increasing the level of voltage applied to the same.

As the temperature of deposition is gradually increased and time passes, deposition of the dielectric component starts. Next, both the dielectric component and metallic component are then deposited at a higher temperature. In the final stage of depositing at a highest temperature, no more of dielectric component z remains, and so the metallic component is exclusively deposited. As a result, as shown in FIGS. 8 and 9, the dielectric component and metallic component have the same concentration to a predetermined depth from the external light entering side of the front plate 70, and then the amount of the dielectric component becomes less and the amount of the metallic component becomes greater.

For this dielectric-metal deposition process, deposition of the metallic component is achieved by melting, rather than by vaporization. In particular, at least one metallic component selected from the group consisting of Fe, Co, V, Ti, Al, Ag, Si, Ge, Y. Zn, Zr, W. Ta, Cu. and Pt has a different phase diagram from that of chromium (Cr). Cr is immediately sublimated by heat, but the above-listed metallic components are melted and changed into the liquid state by the application of heat.

The dielectric component mixed with a liquid metallic component sublimates to be deposited on a plate member of a POP. As the dielectric component sublimates while being mixed with the liquid metallic component, a problem associated with limitation of mass production caused by dielectric particles going out of the deposition boat can be prevented.

The concentration profile of the electrodes and the black matrix pattern varies depending on the initial particle size of the dielectric component. More specifically, if a dielectric material has a particle size as small as about 0.5 mm, the total surface area of the dielectric material increases and its contact surface area with the deposition boat also increases during thermal deposition. The smaller the particle size of the dielectric material, the lighter the weight of the dielectric particles. As a result, a jet flow occurs due to instantaneously increased vapor pressure by thermal conduction, so the dielectric particles go out of the deposition boat, which facilitates the vaporization of the dielectric particles.

In contrast, if a dielectric material has a particle size as large as about 2 mm, the dielectric particles are not affected by jet flow, but the amount of the dielectric material to be deposited is small compared to the total volume of the dielectric material loaded into the deposition boat. As a result, when the particle size of the dielectric component in the mixture of the metallic and dielectric components is adjusted to be within the range of 1-1.5 mm, the second and third electrodes 71 and 72 and the black matrix pattern having optimal optical and electric characteristics can be formed.

When the deposition of the dielectric material and metal is completed, as described above, the resultant thin film deposited on the plate member 70N is patterned by photolithography to complete the formation of either the second and third electrodes 71 and 72 and a black matrix pattern 80 or the second and third electrodes 71 and 72 serving also as the black matrix pattern 80 for the front plate according to the present invention. The deposition of the thin film having the concentration profile of the first and second components is not limited to using the vacuum chamber, and other methods such as sputtering or electron beam deposition may be used to deposit the thin film.

For photolithography, a direct photolithography method or blast photolithography method may be used. According to the direct photolithography to method, a positive photoresist is applied to the deposited thin film, exposed through a shadow mask, and is developed into a photoresist pattern. Next, a predetermined region of the deposited thin film is etched using the photoresist pattern, and the remaining photoresist pattern is removed, thereby forming either the second and third electrodes 71 and 72 and a black matrix pattern 80 or the second and third s electrodes 71 and 72 serving also as the black matrix pattern 80.

For the blast photolithography method, a photoresist is applied to the deposited thin film, and exposed and developed into a photoresist pattern. A black coated layer is formed on the photoresist pattern and unnecessary black coated layer and photoresist pattern are removed by etching, thereby forming either the second and third electrodes 71 and 72 and a black matrix pattern 80 or the second and third electrodes 71 and 72 serving also as the black matrix pattern 80.

The present invention will be described in greater detail by means of the following examples. The following examples are for illustrative purposes and are not intended to limit the scope of the invention. For Embodiments 1 through 9, electrodes and a black matrix pattern are formed on a plate by deposition. For Embodiments 10 through 13, electrodes and a black matrix pattern are formed on a plate by sputtering.

Example 1

mg of a mixture of 25% SiO by weight having a particle size of 1.5 mm and 75% Fe by weight was put into a deposition boat, and the distance between the deposition boat and a plate member was adjusted to 18.5 cm.

The plate member was loaded into a vacuum chamber, and the degree of vacuum was kept at 2x10-3 Pa. A black coated layer having a thickness of 400 nm was deposited on the plate member while varying the temperature of the deposition boat.

After forming the black coated layer on the plate member, an organic positive photoresist was deposited thereon using a centrifuge and exposed through a Jo shadow mask with ultraviolet (UV) rays. The resultant structure was developed and non-exposure region of the photoresist layer was cured to form a photoresist pattern.

The black coated layer was patterned using the photoresist pattern. After cleaning with deionized water, the photoresist pattern was stripped off, resulting either second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern.

Example 2

A black matrix pattern was formed in the same manner as in Example 1, except that the particle size of SiO was 1 mm and 200 mg of the mixture of SiO and iron (Fe) was put into the deposition boat.

Example 3

A black matrix pattern was formed in the same manner as in Example 1, except that 220 mg of a mixture of 40% SiO by weight having a particle size of 1 mm and 60% titanium (Ti) by weight was put into the deposition boat.

Example 4 A black matrix pattern was formed in the same manner as in Example 1,

except that 210 mg of a mixture of 40% SiO by weight having a particle size of 1 mm, 10% Ti by weight, and 50% Fe by weight was put into the deposition boat.

Example 5

A black matrix pattern was formed in the same manner as in Example 1, except that 210 mg of a mixture of 40% SiO by weight having a particle size of 1 mm, 50% Ti by weight, and 10% Fe by weight was put into the deposition boat.

Example 6

A black matrix pattern was formed in the same manner as in Example 1, except that 210 mg of a mixture of 20% SiO by weight having a particle size of 1 mm, to 70% Ti by weight, and 10% Fe by weight was put into the deposition boat.

Example 7

Second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern were formed in the same manner as in Example 1, except that a first deposition boat containing 210 mg of a mixture of 20% SiO by weight having a particle size of 1 mm, 70% Ti by weight, and 10% Fe by weight, and a second deposition boat containing 240 mg of Al were used. After deposition of the mixture, an Al film was in-situ deposited to lower sheet resistance.

Example 8

A black matrix pattern was formed in the same manner as in Example 1, except that 210 mg of a mixture of 20% SiO by weight having a particle size of 1 mm, and 80% vanadium (V) by weight was put into the deposition boat.

Example 9

A black matrix pattern was formed in the same manner as in Example 1, except that a first deposition boat containing 210 mg of a mixture of 20% SiO by weight having a particle size of 1 mm and 80% V by weight and a second deposition boat containing 240 mg of Al were used. After deposition of the mixture, an Al film was in-situ deposited to lower sheet resistance.

The black matrix patterns formed in Examples 1 through 9 were observed using an optical microscope. As a result, second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern formed in Examples 1 through 5 correspond in size and shape to the shadow mask used for exposure and have sharp edges.

Meanwhile, electric and optical characteristics were evaluated for the second and third electrodes serving also as a black matrix pattern, or second and third electrodes and the black matrix pattern formed in Examples 1 through 9. The results are shown in Table 1. In Table 1, R represents sheet resistance, Rm to represents mirror reflectivity, and Rid represents diffused reflectivity.

Table 1

Example Composition (% by weight) R Rm (%)Ret (%) optical Black Matrix (Q/[) Density quality Exurnpe 1 SiO.Fe=25.75 300 1 3 0.08 3.5 ablahckmatiC l Example 2 SiO:Fe = 25:75 745 1.2 0 09 3.5 balahcrkmatiC Exams e SO Ti = 40:60 620 1.1 0.09 4 balahck matic Example 4 SiO Fe T' = 40:10.50 achromatic 500 0.9 0.08 3.8 black Example 5 S'O Fe Ti = 40:50.10 2000 1 0.09 3 3 blahcrkmat'C Example 6 SiO:Fe:Ti = 20:10 70 30 0.8 0 05 4.0 blahckmatic Example 7 S'O:Fe Ti = 20:10:70 & Al 0 1 0.8 0.06 4 5 achromatic layer black Example 8 SiO:V = 20 80 10 0 9 0 05 4 3 achromatic Example 9 SIO V = 20 80 & Al layer 0 08 0 9 0 04 4 7 balahck matic As shown in Table 1, second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern formed in Examples 1 through 9 are in achromatic black and have a mirror reflectivity of about 1% and a diffused reflectivity of 0.08-0.09%. The second and third electrodes and the black matrix pattern can have a sheet resistance of 1 Q/D or less by adjusting the amount of the metal. The optical density of the second and third electrodes and the black matrix pattern is about 4.0. It is evident that reflectivity, resistance, and optical density characteristics of the black matrix pattern and the second and third to electrodes are appropriate for a POP.

For front plates having the black matrix pattern and the second and third electrodes formed in Examples 1 through 9, the striped patterns of the black matrix and second and third electrodes were observed using an optical microscope. As a result, it is apparent that the black matrix pattern and the second and third electrodes s have a good surface flatness and may be formed of fine patterns of 1 Am or less. In other words, the second and third electrodes can be formed as a meshed pattern or as a plurality of parallel line electrodes which are electrically connected and have a separation gap therebetween to the extent that transmittance is not reduced.

Example 10

A black coated layer was deposited to have a thickness of 3,000A on the surface of a plate member by sputtering in a vacuum chamber such that the resultant black coated layer had gradient concentrations of SiOx and Co, as shown in FIG. 10.

After the black coated layer was formed on the plate member, an organic positive z photoresist was deposited on the surface of the black coated layer using a cetrifuger and then exposed to UV light through a shadow mask. The resultant structure was developed and unexposed regions were cured to form a photoresist pattern. The black coated layer was patterned using the photoresist pattern. After cleaning with deionized water, the photoresist pattern was stripped off to form second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern.

Example 1 1

Second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern were formed in the same manner as in Example 10, except that a black coated layer deposited by sputtering had a thickness of 3,300A formed in 10 step gradients of SiOx and Co, as shown in FIG. 11.

Example 12

Second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern were formed in the same manner as in Example 10, except that a black coated layer deposited by sputtering had a thickness of 3,200A formed in 5 step gradients of SiOx and Co.

Example 13

Second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern were formed in the same manner so as in Example 10, except that a black coated layer deposited by sputtering had a thickness of 3,200A formed in 3 step gradients of SiOY and Co. Electric and optical characteristics were evaluated for the second and third electrodes and a black matrix pattern or the second and third electrodes serving also as as the black matrix pattern. The results are shown in Table 2. In Table 2, R represents sheet resistance, Rm represents mirror reflectivity, and Rid represents diffused reflectivity.

Table 2

Example R (Q/n) Rm (%) Rd (%) Thickness Optical Black Matrix (I\) Density quality Example 10 300 1 3 0 05 3000 achromatic 3.5 black Example 11 745 1 S 0.5 3300 achromatic 3.5 black Example 12 620 1 4 0 6 3200 4 aChbrl ckatiC Example 13 500 1 6 0.65 3250 achromatic 3.6 black As shown in Table 2, the second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern formed in Examples 10-13 are in achromatic black and have a mirror reflectivity of 1.3% or greater and a diffused reflectivity of 0.5% or greater. The sheet resistance of the second and third electrodes and the black matrix pattern can be varied by adjusting the amount of metal. The optical density of the second and third electrodes and the black matrix pattern is in the range of 4.1-4.5. It is evident that to reflectivity, resistance, and optical density characteristics of the black matrix pattern and the second and third electrodes are appropriate for a POP.

For front plates having the black matrix pattern and the second and third electrodes formed in Examples 10 through 13, the striped patterns of the black matrix pattern and the second and third electrodes were observed using an optical microscope. As a result, it is apparent that the black matrix pattern and the second and third electrodes have good surface flatness and may be formed as fine patterns.

The front plate, the method for fabricating the front plate, and the POP employing the front plate according to the present invention described above have the following features.

First, second and third electrodes and a black matrix pattern or second and third electrodes serving also as the black matrix pattern are deposited to give the gradient of the concentration profile of metal and dielectric material, which gives good thermal and chemical stability.

Second, although an annealing process is not carried out in forming the electrodes and the black matrix on a plate member of the front plate, the second and third electrodes and the black matrix have good adhesiveness with respect to the plate member and good mechanical characteristics due to the absence of internal stress.

Third, the black matrix and the second and third electrodes may be formed as fine patterns.

Fourth, due to external light absorption effects of the second and third electrodes and the black matrix, the POP has improved contrast characteristics.

The second and third electrodes and the black matrix can easily be made in various patterns.

Fifth, since the black matrix and the second and third electrodes can be s formed to have the same thickness, surface flatness is improved and the level of discharging voltage can be appropriately varied.

While this invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the so spirit and scope of the invention as defined by the appended claims.

Claims (8)

1. A plasma display panel (PDP) comprising: a back plate; first electrodes formed in a predetermined pattern on the back plate; a transparent front plate bonded with the back plate having the first electrodes to form a discharge space therebetween; second and third electrodes formed on one side of the front plate facing the first electrodes at a predetermined angle with respect to the first electrodes; to a barrier wall for partitioning the discharge space between the back plate and front plate; a first dielectric layer formed on the back plate to cover the first electrodes; a second dielectric layer formed on the front plate to cover the second and third electrodes; and a black matrix pattern formed between each pair of the second and third electrodes on the one side of the front plate, wherein the black matrix pattern and either the first electrodes or the second and third electrodes are formed of a dielectric first component and a metallic second component of at least one selected from the group consisting of iron (Fe), cobalt (Co), vanadium (V), titanium (Ti), aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W), tantalum (Ta), copper (Cu), and platinum (Pt).

2. The PDP of claim 1, wherein the first component comprises at least one dielectric material selected from the group consisting of SiOx, MgF2, CaF2, Al2 03, SnO2, In2O3, and ITO, where x>1.

3. The PDP of claim 1 or 2, wherein the amounts of the first and second components gradually change in the thickness direction of the first and second So electrodes and the black matrix pattern.

4. The PDP of claim 1 or 2, wherein the amounts of the first and second components change in step gradients in the thickness direction of the first and second electrodes and the black matrix pattern.

5. The PDP of claim 1, wherein each of the second and third electrodes is formed as a single electrode in a meshed pattern having a plurality of apertures.

6. The PDP of claim 1, wherein the plurality of apertures of each of the to second and third electrodes are formed by a plurality of parallel main electrode portions and a plurality of connect electrode portions connecting the parallel main electrode portions at a predetermined angle.

7. The PDP of claim 1, further comprising an auxiliary indium tin oxide s (ITO) electrode having a predetermined width and extending from each of the second and third electrodes.

8. A plasma display panel (PDP) comprising: a back plate; first electrodes formed in a predetermined pattern on the back plate; a transparent front plate bonded with the back plate having the first electrodes to form a discharge space therebetween; second and third electrodes formed on one side of the front plate facing the first electrodes at a predetermined angle with respect to the first electrodes; 2 a barrier wall for partitioning the discharge space between the back plate and front plate; a first dielectric layer formed on the back plate to cover the first electrodes; a second dielectric layer formed on the front plate to cover the second and third electrodes; and a black matrix pattern formed between each pair of the second and third electrodes on the one side of the front plate, wherein the black matrix pattern and either the first electrodes or the second and third electrodes are formed of a dielectric material and a conductive metal, and the amounts of the dielectric material and conductive metal change in the thickness direction of the electrodes and black matrix pattern.