KR20010111846A - Method for the low temperature vacuum in-line frit sealing of flat panel display device using an auxiliary heat line - Google Patents

Abstract

The present invention discloses a method of manufacturing a flat panel display device composed of a front plate and a back plate.

The method comprises the steps of forming an electrode group of a predetermined pattern on one surface of each of the front plate and the back plate, the main component of PbO, ZnO, B2O3 at the edge of the surface on which at least one electrode group of the front plate and the back plate is formed The first crystalline frit for sealing in a paste state further comprising SiO 2, BaO, SnO 2 is formed by screen printing or dispensing, but the corners are rounded. Forming, heating and calcining the first frit, 'electrically conductive (or radiant heat-absorbing) powder or RuO2 and a metal element (Ag, etc.) based on' Ag, Cu, Pt, Ni, W and the like as a main component A resist powder is formed on the first frit by printing or dispensing a paste made by mixing a frit and a vehicle (hereinafter referred to as "auxiliary heating wire") with the width of the first frit. Have a narrower or the same width, Forming rounded corners in a shape or zigzag shape, heating and calcining the auxiliary heating wire, and ZnO having PbO, B2O3, and SiO2 having a lower plastic temperature than the first frit on the auxiliary heating wire. Forming a second sealing glass frit in a paste state further comprising BaO, SnO2, and Fe2O3 by printing or dispensing, and covering or subtracting all the auxiliary heating wires by making them larger than or equal to the width of the auxiliary heating wires. In the same manner, forming a rounded corner portion, heating and calcining the second frit, and mounting the front plate and the back plate in the vacuum chamber, wherein the surfaces on which the electrode group is formed face each other and are spaced apart from each other by a predetermined distance. After mounting, pumping to maintain a predetermined degree of vacuum, a heat generating field mounted around the front plate and the back plate in the vacuum chamber Heating the first and second frits and auxiliary heating wires formed on the front plate and the rear plate through a heating temperature of 3 to 5 ° C. per minute and heating the final achieved temperature to 200 to 300 ° C. Simultaneously heating the first and second frits and the auxiliary heating wire by applying Joule heat by applying electricity to the auxiliary heating wire at the same time as the firing step by the generator, lowered by impurity gas generated during the firing step and the additional heating step. Pumping to improve the degree of vacuum to the predetermined degree of vacuum, and after the predetermined degree of vacuum is achieved, the front plate and the rear plate are aligned and bonded in a state in which heat by the heat generating device and the additional heating is supplied. Step of lowering the temperature at a rate of 3 to 5 ℃ per minute by adjusting the heating degree and the additional heating degree by the heat generating device after the front plate and the back plate is bonded It is made, including.

Description

Method for the low temperature vacuum in-line frit sealing of flat panel display device using an auxiliary heat line}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a flat panel display for displaying an image signal using an electron beam or plasma, and more particularly, to a low temperature vacuum in-line frit mounting method of a flat panel display device using an auxiliary heating line.

One of the key element technologies in manufacturing flat panel type microelectronic displays such as plasma display panel (PDP), field emission display (FED) and vacuum fluorescent display (VFD) is inside the panel. It is to ensure the initial high vacuum state of the (form). In particular, it is also very important for the FED or VFD to maintain a permanently high vacuum. However, while using displays, impurities such as H ₂ , O ₂ , CO, CO ₂ and N ₂ are out- of the various components such as phosphor screens, glass barrier ribs or spacers and frits inside the panel. Due to gassing, the amount of impurities gradually increases. Such impurities increase the starting voltage of the PDP and lower the luminous efficiency. In the case of FED, the operating voltage for emitting electrons from the emitter is increased and the life time is shortened due to the arc phenomenon. In particular, impurities such as O ₂ and H ₂ O may oxidize cathode metal materials.

In this way, the most reliable way to ensure the initial vacuum in the panel of a flat panel display having a micro space area and a complicated geometry in a high vacuum state is to mount two glass plates inside the vacuum chamber. Vacuum in-line packaging technology. In addition, completing the mounting process in a short time in a low temperature process is absolutely necessary to eliminate the problems caused by thermal deformation or to lower the manufacturing cost.

One example of the prior art is to dispense Frit Paste along the perimeter edge on two glass plates (or one of two glass plates) corresponding to the front plate (top plate) and the back plate (bottom plate) and then 420 ^o. After pre-baking at a temperature of about C, the pixels formed on the front plate and the pixels formed on the back plate are aligned, and then back-baked at a temperature range of 420-450 ^o C. The two glass plates are melt sealed. Next, the glass cupboard to be used as an exhaust tube around the previously made hole in one corner of the back plate is melt-bonded in the same manner as before. The open part of the glass tube is then connected to the pumping port of the pumping system and then heated and evacuated inside the display apparatus panel using a vacuum pump. Once the final vacuum is obtained, the middle part of the glass tube is melted using a torch or a thermal heater to package the tip off panel.

Problems that may occur in the technical case are as follows. Exhaust through the glass tube limits the exhaust conductivity, so that the vacuum inside the panel is more than 100 times lower than the vacuum inside the chamber. In addition, there is a problem that heat deformation and viscosity change occurs in the case of large glass while firing soda glass generally used at 400 ^° C or more.

The present invention is an encapsulation method for improving the degree of vacuum inside the panel, frit paste-type mounting material in the air and 'electrically conductive (or radiant heat absorbing) powders such as Ag, Cu, Ni, W, Mo, Pt, or RuO2 and metal elements. Resistant powder mixed with Ag, etc. and the auxiliary auxiliary wire in the form of frit are applied to the periphery of the front glass plate or the back glass plate with screen printing or dispensing method to the thickness of less than 100㎛, respectively. After the baking process, the two glass plates are mounted in a vacuum chamber, and the sheet is finally heated by radiant heat installed around the panel, and the final melting of the mounting material is performed by using additional heat generated by an auxiliary heating wire coated with frit around the glass plate. By providing a vacuum in-line frit mounting method to perform the sealing process.

Another object of the present invention is to form a paste by mixing a frit of a vitreous type and a crystalline type in an appropriate ratio (50:50 or 60:40) to form a paste, followed by vacuum in-line mounting material. It is possible to keep bubbles and cracks in the range of 200-300 ^o C by heat generated from auxiliary heating wire, and to reduce frit melting temperature by post-baking process in vacuum chamber. It provides a process technology that can be enabled at low temperatures in the 300-350 ^o C range.

1 is a configuration diagram of a PDP and FED panel which is one of flat panel display elements.

2 is a plan view and a cross-sectional view of a panel sealed and encapsulated by forming a frit paste and an auxiliary heating wire according to the present invention.

Figure 3 is a plan view showing a state in which the frit paste and the auxiliary heating wire is applied in a straight line and curved form as an embodiment according to the present invention.

Figure 4 is a plan view showing a state in which the frit paste and the auxiliary heating wire is applied in a zigzag form as an embodiment according to the present invention.

5 is a process flowchart of forming the frit paste and the auxiliary heating wire according to the present invention.

FIG. 6 is a plan view and a cross-sectional view showing a state in which a frit paste and an auxiliary heating line are formed around a hole for encapsulation through a process as illustrated in FIG.

7 is a process flow diagram of vacuum in-line sealing two glass plates according to the present invention.

8 is a process flow diagram of vacuum in-line encapsulation by the present invention.

The present invention relates to a method of manufacturing a flat panel display device consisting of a front plate and a back plate,

Forming an electrode group having a predetermined pattern on one surface of each of the front plate and the back plate;

Forming a sealing first frit in a paste state on the edge of a surface on which at least one electrode group of the front plate and the back plate is formed by a printing method or a dispensing method,

Heating and calcining the first frit,

An electrically conductive (or radiant heat absorbing) paste or resistive paste (hereinafter referred to as "auxiliary heating wire") is formed on the first frit by printing or dispensing, but is formed to have a width that is narrower than or equal to the width of the first frit. Steps,

Heating and calcining the auxiliary heating wire,

On the auxiliary heating wire, a sealing second frit having a plasticity temperature lower than that of the first frit is formed by a printing method or a dispensing method, which covers all the auxiliary heating wires by making them larger than or equal to the width of the auxiliary heating wires. Forming the same as the auxiliary heating wire,

Heating and calcining the second frit,

Mounting the front plate and the back plate in the vacuum chamber, but the surface formed with the electrode group facing each other and mounted so as to be spaced apart by a predetermined distance and pumped to maintain a predetermined degree of vacuum,

Heating and firing the first and second frits and auxiliary heating wires formed in the front plate and the back plate through a heat generating device mounted around the front plate and the back plate in the vacuum chamber;

Simultaneously heating the first and second frits and the auxiliary heating wire by Joule heat by applying electricity to the auxiliary heating wire at the same time as the firing step by the heat generator;

Pumping the vacuum degree lowered by the impurity gas generated during the firing step and the additional heating step to improve the predetermined vacuum degree,

After the predetermined degree of vacuum is achieved, aligning and bonding the front plate and the back plate in a state where heat is supplied by the heat generator and additional heating,

After the front plate and the back plate is bonded to include a step of gradually lowering the temperature by adjusting the heating degree and the additional heating degree by the heat generating device.

In this case, the first frit is crystalline frit, and the second frit is preferably glassy frit. The crystalline frit contains PbO, ZnO, B2O3 as a main component, and further includes SiO2, BaO, SnO2, and the glassy frit contains PbO, B2O3, SiO2 as a main component, and further includes ZnO, BaO, SnO2, Fe2O3. .

In addition, the first frit and the second frit, the auxiliary heating wire is preferably formed to round the corner portion for uniform temperature formation.

More preferably, the auxiliary heating wire is formed in a zigzag shape on the first frit to enhance efficient heat generation and adhesion strength.

The first frit has a thickness of 10 to 100 micrometers and a width of 3 to 10 millimeters, the auxiliary heating wire has a thickness of 10 to 100 micrometers and a width of 2 to 8 millimeters, and the second frit is 100 to 100 micrometers. It is desirable to have a thickness of 500 micrometers and a width of 2 to 10 millimeters.

In addition, the electrically conductive (or radiant heat absorbing) or resistive paste of the auxiliary heating wire contains components such as Ag, Cu, Pt, Ni, Mo, W, RuO2 as main components.

In addition, the heating rate during the heating by the heat generating device is 3 to 5 ℃ per minute and the final achieved temperature is 200 to 300 ℃, the rate of lowering the temperature after joining the front plate and the back plate in the vacuum chamber 3 per minute It is preferable to lower it to -5 degreeC.

In addition, the first and second frits and the first frit and the second frit are formed on the front plate or the back plate for encapsulation. After forming the auxiliary heating wire in the same method and shape, and heat-treated in the same manner for the first and second frit and the auxiliary heating wire formed in the periphery of the sealing hole during the heat treatment for the calcining step and the firing step, It is also possible to further include the step of sealing the sealing material supported by the support portion provided in the lower end of the hole vacuum chamber to the first and second frits and the auxiliary heating wire formed around the sealing hole.

Hereinafter, a step of manufacturing a flat panel display device according to the present invention will be described.

1. Preparation of frit paste

1-1) Powder: Solid powder mainly containing PbO, ZnO, SiO2, B2O3, BaO, SnO2

1-2) Paste Preparation: Viscous liquid made by mixing frit powder and vehicle (solvent mixed with NC and BCA) in a weight ratio of about 6: 1 to 12: 1 and milling more than several hours with a ball miller. Sex paste material

2. Definition of Auxiliary Heat Line paste

2-1) Types of Powder

Powders of electrically conductive (or radiant heat absorbing) metal elements such as Ag, Cu, Pt, Ni, Mo, and W, or resistive powders containing RuO 2 and metal elements (Ag, etc.) and solid powders based on frits

2-2) Preparation of Paste

A viscous liquid paste material made by mixing the powder in an organic vehicle and a solvent containing binders or additives.

3. Primary frit paste line formation

The mixed frit paste is uniformly applied to a thickness of 3-10 mm wide and 100 μm or less by screen printing or dispensing method along the edge on the front or back glass substrate.

4. Formation of metal paste or paste of radiation heat absorbing material

Along the line of the applied frit paste is uniformly applied to a thickness of 2-8mm width, 100㎛ or less by screen printing or dispensing method.

5. Second Frit Paste Line Formation

In order to sufficiently maintain the gap between the front plate and the back plate, uniformly to a thickness of 2-10 mm width and 100 μm or more by dispensing along the applied 'frit paste line / auxiliary film (paste of electrically conductive or radiation absorbing material). To apply.

6. Pre-baking Process

The coated glass substrate is heat-treated in an electric furnace to burn off the solvents contained in the paste. At this time, the temperature is carried out for several minutes at 400 ^° C or more.

7. Place the front and back glass plates into the vacuum chamber.

It may also be transported and mounted in-line from the previous chamber.

8. Carry out the evacuation process to secure the vacuum level of 10 ^-6 torr or more.

9. Post-baking process

The temperature of the heat source (infrared, halogen lamp, arc lamp, etc.) around the panel for heating the glass plate is raised. At this time, the temperature increase rate is about 3-5 ^o C / min, the final achieved temperature is about 200 ^o C to 300 ^o C. At this time, the temperature of the frit is further increased by applying a current to the auxiliary heating wire or by local auxiliary heat by radiation absorption. Wait for the vacuum to return to the 10 ^-6 torr range at the firing temperature. Move the front plate or the back plate to mount two glass plates. Apply a little press for sufficient mounting. Then raise the temperature. The ascent speed is in the range -3 ^o C to -5 ^o C per minute.

10. Transfer of Panel

Transfer to sealed chamber for sealing of sealed panel.

11. Encapsulation Process

Method-1)

In the case of the PDP, the gas is filled through a gas inlet (hole formed in the lower part of the panel), and then a frit applied on a small sealing material (kovar-type metal plate or glass plate) installed under the hole by a local heating heater. Firing is carried out at a temperature of 450 ^° C., and the sealing material placed on the heater is brought into close contact with the hole and the filling is performed in a short time within 1 minute.

Method-2)

The hole of the panel sealed by the same method as the case of sealing the two glass plates is sealed with a local sealing material provided separately in the lower part. That is, frit is melted by the frit and auxiliary heating wire applied around the hole in the lower part of the panel, and sealing is performed by bringing the sealing material beneath it into close contact.

12. Unload the mounted panel.

It can also be transferred in-line into the next chamber.

By using a frit mixed with crystalline frit and vitreous frit, bubbles and cracks generated when using a general sealing frit in a vacuum chamber are not generated. The temperature of the glass substrate can be maintained in the range of 200-300 ^° C., and the frit melting temperature can be made at a low temperature in the range of 300-350 ^° C. by post-baking process in the vacuum chamber.

Claims (12)

In the method for manufacturing a flat panel display device consisting of a front plate and a back plate, Forming an electrode group having a predetermined pattern on one surface of each of the front plate and the back plate; Forming a sealing first frit in a paste state on the edge of a surface on which at least one electrode group of the front plate and the back plate is formed by a printing method or a dispensing method, Heating and calcining the first frit, An electrically conductive (or resistive) paste or radiation absorbing paste (hereinafter referred to as "auxiliary heating wire") is formed on the first frit by printing or dispensing, but is formed to have a width that is narrower than or equal to the width of the first frit. Steps, Heating and calcining the auxiliary heating wire, On the auxiliary heating wire, a sealing second frit having a plasticity temperature lower than that of the first frit is formed by a printing method or a dispensing method, which covers all the auxiliary heating wires by making them larger than or equal to the width of the auxiliary heating wires. Forming the same as the auxiliary heating wire, Heating and calcining the second frit, Mounting the front plate and the back plate in the vacuum chamber, but the surface formed with the electrode group facing each other and mounted so as to be spaced apart by a predetermined distance and pumped to maintain a predetermined degree of vacuum, Heating and firing the first and second frits and auxiliary heating wires formed in the front plate and the back plate through a heat generating device mounted around the front plate and the back plate in the vacuum chamber; Simultaneously heating the first and second frits and the auxiliary heating wire by Joule heat by applying electricity to the auxiliary heating wire at the same time as the firing step by the heat generator; Pumping the vacuum degree lowered by the impurity gas generated during the firing step and the additional heating step to improve the predetermined vacuum degree, After the predetermined degree of vacuum is achieved, aligning and bonding the front plate and the back plate in a state where heat is supplied by the heat generator and additional heating, And a step of gradually lowering the temperature by controlling the heating degree and the additional heating degree by the heat generating device after the front plate and the back plate are bonded. The method of claim 1, wherein the first frit is a crystalline frit and the second frit is a glass frit. The method of claim 2, wherein the crystalline frit is PbO, ZnO, B2O3 as a main component and further comprises SiO2, BaO, SnO2, the glassy frit is PbO, B2O3, SiO2 as a main component ZnO, BaO, SnO2 And Fe2O3, further comprising a flat panel display device manufacturing method. The method of claim 1, wherein the first frit, the second frit, and the auxiliary heating wire are formed to round the corners to form a uniform temperature. The method of claim 1, wherein the auxiliary heating wire is formed in a zigzag shape on the first frit to efficiently generate heat and enhance adhesive strength. The method of claim 1, wherein the first frit has a thickness of 10 to 100 micrometers and a width of 2 to 10 millimeters, and the auxiliary heating wire has a thickness of 10 to 100 micrometers and a width of 2 to 8 millimeters. The second frit has a thickness of 100 to 500 micrometers and a width of 2 to 10 millimeters. According to claim 1, wherein the auxiliary heating wire is a metal powder such as Ag, Pt, Ni, W, Cu, Mo, or a resistive powder in which RuO2 is mixed with a metal element (Ag, etc.) as a 'frit as a main component A method of manufacturing a flat panel display device, characterized in that it is in the form of a viscous paste made by mixing with a solvent containing a binder or additives. The method of claim 1, wherein the heating rate during heating through the heat generating device is 3 to 5 ℃ per minute, the final temperature reached 200 to 300 ℃, the temperature after the front plate and the back plate bonded in a vacuum chamber A method of manufacturing a flat panel display device, characterized in that the speed of lowering is lowered to 3 to 5 캜 per minute. In the method for manufacturing a flat panel display device consisting of a front plate and a back plate, Forming an electrode group having a predetermined pattern on one surface of each of the front plate and the back plate; At least one crystalline first frit for sealing in a paste state including PbO, ZnO, and B2O3 as main components and SiO2, BaO, SnO2 as main components at the edges on the surface where at least one of the electrode groups is formed. ) To form a printing method or a dispensing method to form a rounded corner portion, Heating and calcining the first frit, Created by mixing electrically conductive (or radiant heat-absorbing) metal powders such as Ag, Pt, Ni, Cu, Mo, and W or resistive powders made by mixing RuO2 and metal elements (Ag, etc.) with 'frit, vehicle and additives' Paste (hereinafter referred to as "auxiliary heating wire") is formed on the first frit by a printing method or a dispensing method, the width of which is narrower than or equal to the width of the first frit, and rounded corners in a zigzag form. step, Heating and calcining the auxiliary heating wire, Printing method of sealing second frit for sealing in paste state containing PbO, B2O3, SiO2, which has lower plastic temperature than the first frit, and further comprising ZnO, BaO, SnO2, Fe2O3 on the auxiliary heating wire Or forming by dispensing method to cover the auxiliary heating wires to be larger than or equal to the width of the auxiliary heating wires, or to make them the same as the auxiliary heating wires, and to form corners rounded. Heating and calcining the second frit, Mounting the front plate and the back plate in the vacuum chamber, but the surface formed with the electrode group facing each other and mounted so as to be spaced apart by a predetermined distance and pumped to maintain a predetermined degree of vacuum, The first and second frits and auxiliary heating wires formed on the front plate and the back plate are heated by a heat generator mounted around the front plate and the back plate in the vacuum chamber, and the temperature increase rate is 3 to 5 ° C. per minute. Firing by heating the final achieved temperature to 200 to 300 ℃, Simultaneously heating the first and second frits and the auxiliary heating wire by Joule heat by applying electricity to the auxiliary heating wire at the same time as the firing step by the heat generator; Pumping the vacuum degree lowered by the impurity gas generated during the firing step and the additional heating step to improve the predetermined vacuum degree, After the predetermined degree of vacuum is achieved, aligning and bonding the front plate and the back plate in a state where heat is supplied by the heat generator and additional heating, After the front plate and the back plate is bonded, the step of adjusting the heating degree and the additional heating degree by the heat generating device comprising the step of lowering the temperature at a rate of 3 to 5 ℃ per minute, flat panel display device manufacturing method. 10. The perimeter of the sealing hole according to any one of claims 1 to 9, wherein the first and second frits and the auxiliary heating wire are formed through the at least part of the front plate or the back plate when the first and second frits are formed on the front plate or the back plate. The method further comprises the step of forming the first and second frit and the auxiliary heating wire in the same method and shape. The method of manufacturing a flat panel display device according to claim 10, wherein the first and second frits and auxiliary heating wires formed around the hole for encapsulation during the heat treatment for the calcining step and the firing step are heat-treated in the same manner. . The sealing material supported by the support part installed in the lower end vacuum chamber of the said sealing hole is sealed by adhering to the 1st and 2nd frit and the auxiliary heating wire which were formed around the said sealing hole, Manufacturing method of flat panel display device.