METHOD FOR MANUFACTURING ELECTRODES OF GLASS

PANEL FOR INFORMATION DISPLAY AND GLASS PANEL

MANUFACTURED THEREBY

Technical Field

The present invention relates to a method for manufacturing electrodes of a glass panel for an information display and a glass panel manufactured thereby, and in particular to a method for manufacturing electrodes of a glass panel for an information display and a glass panel manufactured thereby in which an aluminum electrode is formed on a glass substrate which uses a glass as a material including an alkali metal element or an alkali earth metal element.

Background Art

As shown in Fig. 25, the PDP(Plasma Display Panel), which is a kind of a flat type information display instrument, might be formed of a back panel 180 and a front panel 110. Here, the back panel 180 is made of a glass or a metallic substrate, with an address electrode 150 being formed in its one surface. A dielectric layer 190 and a rectangular shaped or waffle shaped partition 160 are formed on the address electrode 150. A phosphorous material is coated in a space between the partitions 160 for thereby forming a sub-pixel. The front panel 110 is formed of a glass substrate, with an electrode

140 being formed in its one surface, and an electric member 120 and a MgO protection layer 130 are formed below the same. The electrode 140 of the front panel 110 will be described more in details. As shown in Fig. 26, it is formed of a sustain electrode 141 and a bus electrode 142. Since the sustain

electrode 141 is a transparent oxide and is electrically conductive, so it is used as an electrode of the front panel 110, and the bus electrode 142 is used for preventing a voltage down which generally occurs in a large size panel. Here, Ag is generally used as a representative material of a bus electrode of the front panel and an address electrode material of the back panel. A paste or sheet containing the powder of Ag is coated or laminated on a glass substrate, and it is patterned in a shape of an electrode by a light exposure and developing method. Since Ag is expensive; it costs a lot to manufacture. The US patent numbers 603037713 and 6517499 disclose a method for using less expensive aluminum as an electrode material.

According to the US patent number 6307713, an aluminum thin film is formed with 500 through 4,000nm thickness on a glass substrate by means of a chemical vacuum vapor and a sputtering method, and it is patterned in a shape of an electrode. A Cr oxide is coated on a surface of an aluminum electrode so as to inhibit an oxidation reaction with an aluminum electrode and a spreading during a plasticity process. In this method, since an aluminum film is made by means of a vacuum deposition method, a manufacturing equipment is expensive, and a productivity is low, so it costs a lot so as to manufacture an aluminum electrode, and an oxide film formation process is additionally needed so as to inhibit a reaction between the electrode and a glass dielectric substance. A long time is needed so as to obtain an electrode having more than 5μm, and a peeling phenomenon that an aluminum thin film is peeled occurs by means of a stress between an aluminum layer and a glass substrate, so it might not properly work.

According to the US patent number 6517400, an aluminum film is laminated and pasted on a surface of a ceramic paste and is patterned in a shape of an electrode. A photoresist might be patterned on a surface of a glass substrate, and Cu is coated for thereby forming an electrode. Ni or Cr is coated so as to inhibit an interfacial oxidation reaction during a plasticity process of an electrode material and a transparent dielectric.

In the above patent, a ceramic paste is additionally needed so as to adhere an aluminum film, and an oxidation reaction prevention layer is additionally needed, and a process for plastic-forming a ceramic paste is further needed so as to adhere aluminum and a glass substrate. The above two conventional arts provide a certain possibility for saving a material cost by substituting an expensive Ag bus and address electrode material with a less expensive aluminum material, but there are problems in the uses of an expensive process equipment and an expensive material or multiple processes, so they cannot be actually adapted because their performance are worse than expected in their performance improvements of a PDP and their cost saving functions.

As a method for forming an aluminum electrode on a glass substrate, an electrode manufacturing method based on an anodic bonding method, not by a deposition and sputtering method, is being intensively developed.

As shown in Fig. 27, according to the above method, an aluminum anodic panel 111 and an aluminum thin plate 105 are disposed on a heater 109 in order, and a glass substrate 103 is disposed on the same, and a cathode panel 101 is disposed on the same, and it is heated at 25O ⁰ C, and 100V DC is applied. Here, a uniform pressure P is applied onto a cathode panel 101 so that an anodic junction can be made in a junction surface between the glass substrate 103 and the aluminum thin plate 105.

Alkali metal or alkali earth metal anodic ion such as potassium contained in the glass substrate is moved toward the cathode metallic electrode member 101 , and the glass substrate 103 and the aluminum thin plate 105 are bonded, so an aluminum thin film is formed on the glass substrate 103. The thusly bonded aluminum film becomes an electrode through a photoresist and light exposure and patterning processes.

In the above electrode manufacture method, since a high temperature sintering process can be omitted when forming an electrode during a bonding of a glass substrate and an aluminum thin plate, additional

facilities are not needed, and work time can be decreased. However, since a contact surface between the glass substrate 103 and the aluminum thin plate 105 and a surface of an apparatus for supplying a pressure are not micro uniform, even when the pressure P is even applied to a front surface of the aluminum thin plate 105 through a cathode panel 101 , it is actually impossible to apply an uniform pressure between the glass substrate 103 and the aluminum thin plate 105. In particular, it is more actually impossible to apply an uniform pressure onto the whole surfaces of a large size surface in a glass substrate used for a flat type information display, and an anodic junction strength might be non-uniform, and an anodic junction might not occur. During the pressurizing process, air or moisture might be inputted into an interfacial portion between the glass substrate and the aluminum thin plate. It is impossible to basically inhibit the occurrence of such problems. Since a non-bonded portion occurs, the above conventional method cannot be actually used as a method for forming an aluminum electrode on a glass substrate.

Due to the above problems, Ag is currently used as an electrode material formed on a glass substrate. When an Ag electrode, which is used as a window glass other than a currently-used aluminoborosilicate glass, is formed on a cheap soda-lime glass, since the Ag electrode is processed through a sintering process for a long time at above 500 ⁰ C, a yellowing phenomenon, in which a glass substrate turns yellow, occurs during a sintering process, which leads to a defect in product. So, as a glass substrate of a PDP, a soda-lime glass is not used. So as to manufacture a PDP, since it is needed to use an expensive aluminoborosilicate glass substrate and an expensive Ag electrode are used, the basic materials cost a lot, and it is impossible to save a unit price of the product.

DISCLOSURE OF THE INVENTION Technical Problem

Accordingly, it is an object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display and a glass panel manufactured thereby, which overcomes the problems encountered in the conventional art.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, which is able to manufacture a glass panel at a lower cost in such a manner that a cheap electrode material such as an aluminum thin plate is bonded with a thin film on a glass substrate including a cheap alkali metal or alkali earth metal such as a soda-lime glass.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, in which an aluminum thin plate can be bonded to a large size glass substrate of above 80 inches without air foam or swelling irrespective of sizes in such a manner that a cleaning room is formed between an aluminum thin plate and a glass substrate, and the opposing bonding surfaces of a glass substrate and an aluminum thin plate, which form a cleaning room, are cleaned by means of an atmospheric process plasma or ultraviolet ray, and an aluminum thin plate is bonded to a glass substrate in a form of a film by means of an anodic bonding in a state that a glass substrate and an aluminum thin plate are made closer with each other.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, which is able to save an electrode manufacturing cost on a glass panel by making it possible not to use an expensive and long time sintering process and not to use expensive related facilities by using an aluminum thin plate like a paste having a conventional metallic(Ag, etc) is used.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, in which an exhaust can be performed between a lower surface of a spacing

member and an upper surface of a glass substrate by maintaining a certain space between an aluminum thin plate and an edge of a glass substrate using a spacing member.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, in which an aluminum thin film can be reliably bonded to a glass substrate by uniformly pressing an aluminum thin plate, bonded to a glass substrate, using a scrapping member, so as to overcome the defects of an electrode which occur by means of a surface roughness of an aluminum thin plate boded to a glass substrate in a form of a thin film.

It is another object of the present invention to provide a method for manufacturing electrodes of a glass panel for an information display, in which a bonding of an aluminum thin plate in a glass substrate might be reliable by properly adjusting a moving speed of an alkali metal or alkali earth metal anodic ion in a glass substrate in such a manner that a voltage supplied to a metallic electrode member, on which a glass substrate is disposed for an anodic bonding of a glass substrate and an aluminum thin plate, is increased step by step up to a certain lever.

It is another object of the present invention to provide a glass panel manufactured by a method for manufacturing electrodes of a glass panel for an information display.

Technical Solution

To achieve the above objects, there is provided a method for manufacturing electrodes of a glass panel for an information display which comprises a step in which a glass substrate 3 containing an alkali metal or alkali earth metal element is mounted on an electrode member 1 ; a step in which an aluminum thin plate 5 is arranged on the glass substrate 3 mounted on the electrode member 1 ; a close contact step in which in a state

that an atmosphere pressure is applied to one side of the aluminum thin plate 5, a space between one side of the glass substrate 3 and the other side of the aluminum thin plate 5 maintains vacuum, and the other side of the aluminum thin plate 5 and one side of the glass substrate 3 are closely contacted by means of a pressure applied to one side of the aluminum thin plate 5; a bonding step in which the glass substrate 3 maintains a certain temperature, and a voltage is supplied between the electrode member 1 and the aluminum thin plate 5 with the electrode member 1 being set as a cathode and the aluminum thin plate 5 being set as an anode, so one side of the glass substrate and the other side of the aluminum thin plate 5 are bonded; and a step in which an aluminum thin plate bonded to the glass substrate 3 is patterned for thereby forming an electrode on the glass substrate.

To achieve the above objects, there is provided a method for manufacturing electrodes of a glass panel for an information display, which comprises a preparation step S110 in which a glass substrate 3 containing alkali metal element or alkali earth metal element and an aluminum thin plate 5 are spaced and arranged between a pair of electrode members 1 and 7; a bonding surface cleaning step S120 in which the opposite bonding surfaces of the glass substrate 3 and the aluminum thin plate 5 are cleaned in such a manner that an atmospheric process plasma is generated between the glass substrate 3 and the aluminum thin plate 5 by applying an AC voltage between a pair of the electrode members 1 and 7, and the foreign substances cleaned from the bonded surfaces are discharged to the outside; a close contact step S130 of the glass substrate and the aluminum thin plate for closely contacting the aluminum thin plate 5 and the glass substrate 3 in a state that a space between the glass substrate 3 and the aluminum thin plate 5 is made vacuum; a bonding step S140 of the glass substrate and the aluminum thin plate in which in a state that the glass substrate 3 has a certain temperature, a DC voltage is applied between the electrode member

1 and the aluminum thin plate 5 with the electrode member 1 being set as a

cathode and the aluminum thin plate 5 being set as an anode, so that the glass substrate 3 and the aluminum thin plate 5 are bonded with each other; and an electrode formation step S150 for forming an electrode on the glass substrate 3 by patterning an aluminum film bonded to the glass substrate.

To achieve the above objects, there is provided a glass panel for an information display which is manufactured by the above methods.

Advantageous Effect

In the present invention, it is possible to manufacture a glass panel at a lower cost in such a manner that an electrode is manufactured by bonding a low cost electrode material such as an aluminum thin plate in a form of a thin film on a glass substrate which contains a low cost alkali metal or alkali earth metal element such as an aluminoborosilicate as well as a soda-lime glass.

In addition, according to an electrode manufacturing method of an information display glass panel, it is possible to manufacture an electrode by bonding aluminum with a thin panel while preventing air foams and a folding of a thin film even in a large size glass panel. Since it is possible to substantially remove foreign substances attached on the opposite bonding surfaces in which a glass substrate and an aluminum thin plate are opposite to each other, an aluminum thin plate is closely contacted on a glass substrate, so it is possible to prevent an aluminum film from being swollen. So, a bonding defect of an aluminum electrode occurring due to a swelling phenomenon can be previously prevented. Since a better aluminum electrode can be formed on a glass substrate, the reliability of product can be enhanced, and a product yield and a product uniformity can be enhanced.

Since the method for manufacturing an electrode of an information display glass panel is capable of removing a conventional sintering process

of an electrode, the process for manufacturing a panel is decreased, and a process productivity is enhanced.

In addition, according to a method for manufacturing an electrode of an information display glass panel of the present invention, when an aluminum thin plate is closely contacted with a glass substrate, oxygen might be small in a space between an aluminum thin plate and a glass substrate under vacuum, so an oxide formation such as AI ₂ O ₃ might be inhibited from a close contact surface of an aluminum thin plate, whereby it is possible to maximize a bonding force of an aluminum thin plate, and an aluminum electrode.

Brief Description of the Drawings

Fig. 1 is a flow chart of an electrode manufacturing method of a glass panel according to a first embodiment of the present invention.

Fig. 2 is a schematic front view illustrating a step for mounting a glass substrate on an electrode member according to a first embodiment of the present invention.

Fig. 3 is a schematic front view illustrating a step for mounting a spacing member on a glass substrate according to another embodiment of the present invention.

Fig. 4 is a schematic front view illustrating a step for mounting an aluminum thin plate on a glass substrate according to a first embodiment of the present invention. Fig. 5 is a schematic front view illustrating a step for making an aluminum thin plate be closer on a glass substrate according to a first embodiment of the present invention.

Fig. 6 is a detailed view of the portion A of Fig. 5. Fig. 7 is a schematic front view illustrating a step for bonding an aluminum thin plate on a glass substrate according to a first embodiment of the present invention.

Fig. 8 is a schematic front view illustrating a step for forming an electrode according to a first embodiment of the present invention.

Fig. 9 is a graph of a relationship between a voltage supply time and a voltage intensity when a certain voltage is supplied so as to bond an aluminum thin plate on a glass substrate according to a first embodiment of the present invention.

Fig. 10 is a graph illustrating a relationship between a voltage supply time and a voltage intensity when a voltage, which is increased step by step, is supplied so as to bond an aluminum thin plate on a glass substrate according to a first embodiment of the present invention.

Fig. 11 is a graph illustrating a relationship between a voltage supply time and a voltage intensity when supplying a pulse voltage so as to bond an aluminum thin plate on a glass substrate according to a first embodiment of the present invention. Fig. 12 is a graph illustrating a relationship between a voltage supply time and a voltage intensity when a pulse voltage, which is increased step by step, is supplied so as to bond an aluminum thin plate on a glass substrate ■ according to a first embodiment of the present invention.

Fig. 13 is a flow chat of an electrode manufacturing method of a glass panel according to a second embodiment of the present invention.

Fig. 14 and 15 are schematic views for describing a preparation step according to a second embodiment of the present invention.

Fig. 16 and 17 are horizontal cross sectional views illustrating an electrode member of Fig. 14. Fig. 18 is a schematic front view illustrating a state that a glass substrate is mounted on an electrode member according to a second embodiment of the present invention.

Fig. 19 is a schematic front view illustrating a state that an aluminum thin plate is mounted on a glass substrate according to a second embodiment of the present invention.

Fig. 20 is a schematic front view illustrating a bonded surface cleaning step for cleaning the opposite bonding surfaces of an aluminum thin plate and a glass substrate by means of an atmospheric process plasma occurring in an electrode member according to a second embodiment of the present invention.

Fig. 21 is a partially enlarged view illustrating the portion B of Fig. 20.

Fig. 22 is a schematic front view illustrating a closer contacting step between a glass substrate and an aluminum thin plate according to a second embodiment of the present invention. Fig. 23 is a schematic front view illustrating a bonding step between a glass substrate and an aluminum thin plate according to a second embodiment of the present invention.

Fig. 24 is a schematic front view illustrating an electrode formation step for forming an electrode according to a second embodiment of the present invention.

Fig. 25 is a cross sectional perspective view of a structure of a conventional PDP.

Fig. 26 is a view illustrating a conventional front glass panel.

Fig. 27 is a schematic front view illustrating an electrode manufacturing method by means of a conventional anodic bonding for bonding an aluminum thin plate on a glass substrate.

Best Mode for Carrying Out the Invention

The method for manufacturing a glass panel for an information display according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Fig. 1 through 12 are views for describing a method for manufacturing an electrode of a glass panel for an information display according to a first embodiment of the present invention.

As shown in Fig. 1 , the method for manufacturing an electrode of a glass panel for an information display according to a first embodiment of the present invention comprises a glass substrate arrangement S1 on an electrode member, an aluminum thin plate arrangement S20 on a glass substrate, a close contact S30 of an aluminum thin plate with a glass substrate, a bonding S40 of a glass substrate and an aluminum thin plate, and an electrode formation S50. Each step will be described in details.

In the step S10 for arranging a glass substrate on the electrode member, as shown in Fig. 2, an electrode member 1 is prepared on a table 13. A glass substrate 3 having a certain area is placed on the electrode member 1. Here, it is preferred that a sealing packing 14 is disposed in an outer side of the electrode member 1 for a close contact with the glass substrate 3.

A metal or electrolyte might be used for the electrode member 1 and an alkali metal element or an alkali earth metal element might be used for a glass substrate 3. An aluminoborosilicate glass or a soda-lime glass, which is widely used as a common window glass, is included.

In the step S20 for arranging an aluminum thin plate on the glass substrate, as shown in Fig. 4, an aluminum thin plate 5 having an area wider than the glass substrate 3 is disposed on the glass substrate 3. Here, the term of the aluminum thin plate means an aluminum foil and an aluminum film.

Between the step S10 and the step S20, as shown in Fig. 3, a step for arranging a spacing member might be inserted so as to space the aluminum thin plate 5 from an edge of the glass substrate 3.

As shown in Fig. 6, the spacing member is provided so as to achieve an efficient air exhaust between a lower surface of the spacing member 4 and an upper surface of the glass substrate 3 when making a space between the glass substrate 3 and the aluminum thin plate 5 a vacuum state. As shown in Fig. 5 and 6, in the close contact step S30 of the glass substrate and the aluminum thin plate, a vacuum pressure Pi is set to be

applied to a space between a lower surface of the aluminum thin plate 5 and an upper surface of the glass substrate 3 with an atmosphere pressure Po being applied to an upper surface of the aluminum thin plate 5. So, the aluminum thin plate 5 can be closely contacted with an upper surface of the glass substrate 3 with the help of a pressure difference between the atmosphere pressure Po of an upper surface of the aluminum thin plate 5 and a lower surface of the aluminum thin plate 5.

In the above step, various methods might be used so as to apply a vacuum pressure to a space between a lower surface of the aluminum thin plate 5 and an upper surface of the glass substrate 3. For example, an air exhaust port might be formed in an outer side where the glass substrate is installed in the table 13, and a vacuum line 8 and an opening and closing switch 9 and a vacuum pump VP are installed in the exhaust port.

When the vacuum pump VP is operated so as to apply a vacuum pressure to the space, air and moisture residing in a space between the glass substrate 3 and the aluminum thin plate 5 are discharged to the outside through an exhaust port as shown by the arrow of Fig. 6, so the space becomes a vacuum state. At this time, when a spacing member 4 is installed so as to space the aluminum thin plate 5 from an edge of the glass substrate 3, since the air is discharged through a space between a lower surface of the spacing member 4 and an upper surface of the glass substrate 3 as shown by the arrow, so an exhaust can be more efficiently performed.

When the vacuum pump VP is operated in a state that a spacing member 4 is not installed in an edge of the glass substrate 3, since the aluminum thin plate 5 first contacts with the glass substrate 3 near the exhaust port, so the aluminum thin plate 5 is uniformly close-contacted over the whole surface of the glass substrate 3. Here, the portions between the glass substrate 3 and the aluminum thin plate 5 might be partially folded and air foams might occur, but when the spacing member is installed, the portion between the edge of the glass substrate 3 and the aluminum thin plate 5 is

spaced by the height of the spacing member 4 by means of the spacing member 4, and the spacing member 4 has a very small space with respect to the upper surface of the glass substrate 3 by means of a surface roughness of the spacing member 4. So, when the vacuum pump VP is operated, since the exhaust can be continuously performed between the lower surface of the spacing member 4 and the upper surface of the glass substrate 3 as indicated by the arrow, the air foams are not formed in the aluminum thin plate 5 and the glass substrate 3 along with a perfect close contact. When a vacuum space is maintained between the glass substrate 3 and the aluminum thin plate 5, the aluminum thin plate 5 can be uniformly close-contacted over the whole surfaces of the glass substrate 3 without air foams in the interfacial portions between the aluminum thin plate 5 and the glass substrate 3 by means of the atmosphere pressure applied to the surface of the aluminum thin plate 5. With the above close-contacts, pressures are uniformly applied toward the whole surfaces of the glass substrate 3 having a large size, so the aluminum thin plate can be uniformly bonded in the following processes.

Here, when the whole surfaces are uniformly pressed by means of a scraping means such as a rubber spoon after the aluminum thin plate 5 is closely contacted the glass substrate 3, a bonding performance between the aluminum thin plate 5 and the glass substrate 3 can be enhanced.

The vacuum pump VP might be formed of a rotary pump, a rotary pump/diffusion pump for a higher vacuum performance or a rotary pump/turbo pump. It is preferred that the vacuum degree in the space by means of the vacuum pump is 10 through 10 ^~6 torr, and more preferable in 10 ² through 10 ^"6 torr.

As shown in Fig. 7, in the bonding step S40 of the glass substrate and the aluminum thin plate, the glass substrate 3 maintains a certain temperature, and voltage is applied between the electrode member 1 and the aluminum thin plate 5 with the electrode member 1 being set as a

cathode and the aluminum thin plate 5 being set as an anode. In this step, alkali metal or alkali earth metal element contained in the glass substrate 3 moves to the lower side of the glass substrate 3, so one side of the glass substrate 3 and the other side of the aluminum thin plate 5 are bonded. Precipitated alkali metal or alkali earth metal ions, namely, potassium positive ions (Na ⁺ ) discharged from the lower side of the glass substrate 3 are preferably wiped with water later.

It is preferred that an insulation plate 9 is installed on an upper surface of the table 13 where the aluminum thin plate 5 is placed, for thereby insulating the aluminum thin plate 5, which was conducted with positive electricity, from the table 13 which is to be conducted with negative electricity.

In the present invention, as a proper process variable of the anode reaction, the bonding temperature is 100 through 50 ⁰ C, and the bonding time is 1 minute to 2 hours, and the bonding voltage is 150V through 1500V, and the bonding temperature should not exceed 500 ⁰ C because heating and cooling time might be extended, and the glass substrate might be smoothened. The longer the bonding time, the higher the bonding performance of the aluminum thin plate, so it is preferred that the bonding time is extended if possible. The bonding voltage should not exceed 1500V in consideration with a breakdown voltage of the glass, and more preferably the bonding temperature is 250 through 300°C, and the bonding time is 10 minutes through 30 minutes, and the bolding voltage is 500V through 1000V.

At this time, when the voltage to be supplied to the electrode member is sharply increased, air foams might be formed between the aluminum thin plate 5 and the glass substrate 3, so it is preferred that the voltage is increased step by step up to a certain level. As shown in Fig. 9, the DC voltage of 500V might be constantly applied, but as shown in Fig. 10, the voltage is supplied intermittently or step by step between OV to 500V, and then the DC voltage of 500V is maintained for a certain time. As shown in

Fig. 11 , the voltage supply of OV to 500V might be intermittently repeated by

a certain number, and an intermittent DC voltage of OV to 500V is maintained for a certain time. As shown in Fig. 12, the voltage supply might be intermittently repeated in a range of OV to 100V, OV to 200V or OV to 500V, and then the voltage is maintained in a range of OV to 500V for a certain time, so it is possible to obtain the optimum anode bonding by properly adjusting the moving speed of the aluminum ions based on the increase of the voltage.

As shown in Fig. 8, in the electrode formation step S50, the aluminum thin film 5' bonded to the glass substrate 3 is patterned in various types of electrodes for forming the electrode on the glass substrate 3.

The process for forming the electrode is to use the known art, so the detailed description thereof will be omitted. As one example, a photoresist is coated on a surface of the aluminum thin film 5' bonded to the glass substrate 3, and it is developed by means of a light exposure method in a shape of a spacing electrode or an address electrode for thereby forming an etching protection pattern film. In the thusly prepared sample, a portion not protected by means of a photoresist is chemically etched using an aluminum etching solution for thereby forming an aluminum electrode 5" pattern, which is used for a front or back plate 10 of the PDP panel. In the same manner as the above, an aluminum electrode 5" might be formed on a glass substrate 3 which uses a glass containing alkali metal or alkali earth element, and the aluminum electrodes are patterned in various shapes and are used as a front or back plate of the glass panel for an information display for thereby manufacturing a PDP. Many methods are already known in the art, the detailed descriptions are omitted.

Fig. 13 through 24 are views illustrating an electrode manufacturing method of a glass panel for an information display according to a second embodiment of the present invention.

As shown in Fig. 13, the method for manufacturing an electrode of a glass panel for an information display according to a second embodiment of the present invention comprises a preparation step S110, a bonding surface

cleaning step S120, a close contacting step S130 of a glass substrate and an aluminum thin plate, a bonding step S140 of a glass substrate and an aluminum thin plate, and an electrode formation step S150. As compared to the method for manufacturing an electrode of a glass panel for an information display according to a first embodiment of the present invention, the preparation step S110 and the bonding surface cleaning step S120 are further provided. Each step will be described as follows.

As shown in Figures 14 and 15, in the preparation step S110, a glass substrate 3 and an aluminum thin plate 5 are arranged between a pair of electrode members 1 and 7.

The same glass substrate 3 and aluminum thin plate 5 as the first embodiment of the present invention are used. As shown in Fig. 14 and 15, the aluminum thin plate 5 having an area larger than the area of the glass substrate 3 is disposed on the glass substrate 3. An electrode member 1 is arranged in a lower side of the glass substrate 3, and an electrode member 7 is disposed on an upper side of the aluminum thin plate 5, and a cleaning space 31 is formed between the glass substrate 3 and the aluminum thin plate 5.

The electrode member 1 might be formed of a flat metallic plate or a liquid substance such as an electrolyte.

The electrode member 7 might be formed in various types. As shown in Fig. 14, a rod shaped electrode member includes a rod shaped metallic core 71 , and a ceramic outer layer 73 which surrounds the metallic core 71 as shown in Fig. 16. As shown in Fig. 17, it is preferred that a filter 75 is filled in a gap g of the ceramic outer layer 73 so as to enhance a plasma discharge efficiency. The filler 75 might be a certain material which can be attached between the metallic core 71 and the ceramic outer layer 73 as an insulator. For example, epoxy or ceramic cement might be used. As shown in Fig. 15, in case that the electrode member 7 is formed in a flat shape, the electrode member 7 includes an insulator 75 made of the same materials as a ceramic material installed on an upper side of the aluminum thin plate 5,

and a metallic flat plate 76 which is attached to an upper side of the insulator 75. The metallic flat plate 76 is made of a stainless steel or aluminum.

Various methods for spacing the glass substrate 3 and the aluminum thin plate 5 might be used. For example, the apparatuses of Fig. 18 through 20 might be used.

As shown in Fig. 18 through 20, a glass substrate 3 having a certain area shown in Fig. 18 is mounted on an upper side of the electrode member 1 which moves up and down in the interior of the table 13, and an aluminum thin plate 5 shown in Fig. 18 is mounted on an upper side of the table 13, and an electrode member 1 shown in Fig. 20 moves down along with the glass substrate 3, so a cleaning space 31 is formed between the glass substrate 3 and the aluminum thin plate 5.

The shorter the distance between the glass substrate 3 and the aluminum thin plate 5, the better the generation of the atmospheric process plasma. If the distance is too small, two electrode might collide with each other, two electrodes are neared by 2~3mm, and the distances are 7~8mm.

The electrode member 1 might be configured to move up and down in various methods. For example, as shown in Fig. 20, there are provided a transfer screw 17 engaged to a lower center portion of a base frame 15 which supports the electrode member 1 , a pair of bevel gears 19 which engaged to a lower side of the transfer screw 17, and a height adjusting handle 21 which is able to rotate the bevel gear 19. Except the above elements, various types might be adapted. Reference numeral 14 means a sealing packing. As shown in Fig. 21 , the table 13 includes spacing members 23 and

24 made of rubber materials and disposed on its upper side. A first vacuum passage 29 is formed in an inner side of the table 13 where the inner spacing member 23 is placed. A second vacuum passage 30 is formed in an outer side of the table 13 where the outer spacing member 24 is placed. The first vacuum adsorption port 26 connected with the first vacuum passage 29 is open toward a passage 25 between the table 13 and the electrode

member 1 , and the second vacuum adsorption port 28 connected with the second vacuum passage 30 is open toward a groove 27 between the inner and outer spacing members 23 and 24.

The air is sucked from the interior of the groove 27 through the second vacuum adsorption port 28 and is discharged to the outside, so the aluminum thin plate 5 placed on the table 13 is made flat, and the air is sucked from the interior of the passage 25 through the first vacuum adsorption port 26, so the interior of the passage 25 becomes vacuum. So, the foreign substances cleaned during the cleaning step are discharged to the outside.

Next, as shown in Fig. 14 and 20, in the bonding surface cleaning step S120, an atmospheric process plasma is generated between the glass substrate 3 and the aluminum thin plate 5 by applying an AC voltage between a pair of the electrode members 1 and 7, so the opposite bonding surfaces of the glass substrate 3 and the aluminum thin plate 5 are cleaned, so the foreign substances cleaned from the bonded surfaces are discharged to the outside.

Here, the terms of the foreign substances means micro dusts or air elements, namely, gas particles such as O ₂ , N ₂ , CO ₂ , moisture, etc or air element gases chemically adsorbed or impurities which might block an anodic bonding between the glass substrate and the aluminum thin plate, which are all adsorbed to the surfaces where the aluminum thin plate 5 and the glass substrate 3 are opposite to each other. Namely, by removing foreign substances it is possible to prevent a strength down of the anodic bonding and a blister phenomenon in an interfacial portion between the glass substrate and the aluminum thin plate, which problems might cause a defect in the electrode in the interfacial portion between the glass substrate 3 and the aluminum thin plate 5 when bonding the aluminum thin plate 5 on the glass substrate 3. So as to generate an atmospheric process plasma, an AC voltage of

5000 through 25000V having 50Hz through 5OkHz is applied between the

electrode members 1 and 7, and as shown in Fig. 20, an inactive gas such as Ar, Ne, He, etc. is inputted into the cleaning space 31 through a gas injection port 16 which passes through the base frame 15, so it is possible to enhance a discharge efficiency and a stability as compared to before the 5 injection of an inactive gas. At this time, an inactive gas which gathers from the base frame 15 is small and naturally discharged to the outside through the first vacuum adsorption port 26, so there is not any problem for making the cleaning space 31 an inactive gas environment. So as to make the aluminum thin plate 5 tightened and fixed, the first vacuum adsorption port i o 26 remains closes at a first stage, but as the Ar gas is injected, it is open and maintains opened in the following processes.

When an AC voltage is applied between a pair of electrode members 1 and 7, atmospheric process plasma occurs between the glass substrate 3 and the aluminum thin plate 5. At this time, when the electrode member 7 is

15 made in a rod shape, a scanning operation that the rod shaped electrode member 7 moves in parallel on the upper side of the aluminum thin plate 5 is repeatedly performed, so the foreign substances attached to the bonded surfaces where the aluminum thin plate 5 and the glass substrate 3 are effectively separated and floated in the cleaning space 31 .

20 So as to discharge the foreign substances floating in the cleaning space 31 to the outside, an AC voltage applied to generate atmospheric process plasma is first disconnected, and the atmospheric process plasma is removed, and the atmospheric process plasma is remained until the glass substrate 3 and the aluminum thin plate 5 get closer to each other by about

25 1 ~2mm, not contacting with each other, and in this state, the electrode member 1 and the glass substrate 3 are approached toward the aluminum thin plate 5, and a vacuum negative pressure applied to the passage 25 and the cleaning space is gradually increased through the first vacuum adsorption port 26, so the foreign substances floated in the cleaning space

30 31 are discharged to the outside through the first vacuum adsorption port 26,

whereby the opposite bonding surfaces of the glass substrate 3 and the aluminum thin plate 5 are cleaned.

Next, as shown in Fig. 22, in the close contact step S130 of the glass substrate and the aluminum thin plate, the aluminum thin plate 5 and the glass substrate 3, which remain spaced from each other, are closely contacted. In a state that the generation of atmospheric process plasma is stopped, the electrode member 1 is moved upward, so the glass substrate 3 is made closer to the aluminum thin plate 5, and the air remaining in the cleaning space 31 is removed by means of a vacuum negative pressure Pi applied through the first vacuum adsorption port 26. When the glass substrate 3 is contacted with the aluminum thin plate 5, the aluminum thin plate 5 is closely contacted onto an upper surface of the glass substrate 3 with the help of a pressure difference between the pressure Po applied to an upper surface of the aluminum thin plate 5 and a vacuum negative pressure Pi applied to a lower surface of the aluminum thin plate 5.

As the space between the glass substrate 3 and the aluminum thin plate 5 becomes vacuum, the opposite bonding surfaces of the aluminum thin plate 5 and the glass substrate 2 are uniformly bonded without air foams, blisters or non-folded states. With the above performance, it is possible to manufacture a good quality aluminum electrode by uniformly maintaining a pressing pressure with respect to the aluminum thin plate 5 throughout the whole surfaces of the glass substrate 3 having a large surface area.

At this time, the vacuum degree of the space between the glass substrate 3 and the aluminum thin plate 5 is the same as the first embodiment of the present invention while the glass substrate and the aluminum thin plate are closely contacted.

As shown in Fig. 23, in the bonding step S140 of the glass substrate and the aluminum thin plate, the aluminum thin plate 5 closely contacting with the upper surface of the glass substrate 3 is bonded with the glass substrate 3. In a state that the glass substrate 3 maintains a certain

temperature by heating the electrode member 1 using a heater 6, a DC voltage is applied between the electrode member 1 and the aluminum thin plate 5 so that the electrode member 1 becomes a cathode, and the aluminum thin plate 5 becomes an anode. In this state, alkali metal or alkali earth metal elements contained in the glass substrate 3 move to a lower surface of the glass substrate 3, so the upper surface of the glass substrate 3 is bonded with the lower surface of the aluminum thin plate 5. At this time, the alkali metal or alkali earth metal ions, for example, precipitation substance such as potassium positive ion(Na+), which are discharged on the lower surface of the glass substrate 3, are wiped and cleaned using water.

The performance of the bonding of the glass substrate 3 and the aluminum thin plate 5 and the voltage supplied to the electrode member 1 are the same as the first embodiment of the present invention.

As shown in Fig. 24, in the electrode formation step S150, the aluminum film 5' bonded on the glass substrate 3 is patterned for thereby forming an aluminum electrode 5" on the glass substrate 3. The detailed process might be implemented by means of the art known before the present invention is filed and might be the same as the first embodiment of the present invention, so its description will be omitted. The glass panel for an information display manufactured by a method for manufacturing an electrode of a glass panel of an information display according to the first and second embodiments of the present invention does not limit the kinds of the glass substrates to a conventional aluminoborosilicate glass. Namely, a soda-lime glass, which is currently and widely used, might be used, so it is possible to significantly decrease the manufacture cost as compared to the glass panel for an information display manufactured by means of the conventional methods.

In the above descriptions, the electrode manufacture method of the present invention is described while limiting to the PDP panel, but its application is not limited thereto. If necessary, the present invention might be applied to a LCD panel, a Xe flat lamp or something.

Industrial Applicability

As described above, according to the method for manufacturing an electrode of a glass panel for an information display, a cheap electrode material such as an aluminum thin plate can be bonded on a glass substrate containing cheap alkali metal or alkali earth elements such as aluminoborosilicate glass as well as soda-lime glass so as to manufacture an electrode for thereby manufacturing a glass panel at a low cost. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described examples are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.