KR20000001614A - Plasma display panel and fabricating method of the same - Google Patents

Abstract

PURPOSE: A plasma display panel is provided to prevent a MgO film from being exposed to the atmosphere. CONSTITUTION: The device comprise a upper electrode formed on a front substrate, a lower electrode formed on a back substrate, dielectric layers covering with the respective electrode, and protective film of MgO formed thereon. The MgO film is covered with a LaF3 film. It is possible to prevent humidity invasion of the MgO film, thereby improving the ejection of secondary electrons and the addressing quality of the display.

Description

Plasma Display Panel And Method Of Manufacturing The Same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel and a method of manufacturing the same, and more particularly, to a plasma display panel in which a thin film for inhibiting moisture absorption is deposited on an MgO protective film of a front substrate and a method of manufacturing the same.

Display, one of the tools of the information revolution of the 20th century, can be divided into CRT and FLAT PANEL DISPLAY, which is thinner, easier to carry, and consumes less power than conventional CRT. At the same time, it is forming a new area of market while compensating for the shortcomings of existing CRTs.

Such flat display devices include LCD (Liquid Crystal Display), PDP (Plasma Display Panel), and FED (FIELD EMISSION DISPLAY). .

1 is a schematic cross-sectional view of a conventional plasma display panel.

As shown in the drawing, a conventional PDP is a flat panel display element having discharge cells in which a space between the rear substrate 1 and the front substrate 8 facing each other is separated by a partition wall 4. The discharge cell is a plasma discharge space divided to correspond to each pixel by forming the partition wall 4 on the back substrate 1.

By discharging by the voltage applied through the lower electrode 2 and the upper electrode 7 formed in a stripe in the direction crossing each other on the opposite surface of the back substrate 1 and the front substrate 8 in such a discharge space. The image will be displayed. The upper and lower electrodes 2 and 7 are respectively covered by the dielectric layers 3.

Such a PDP forms a partition 4 on the back substrate 1 to create a plasma discharge space, thereby causing a discharge in the discharge space to display an image. The partition 4 is usually formed by a printing method, and a pattern must be formed constantly. By doing in this way, the image by the discharge between adjacent cells can be clearly distinguished and viewed by the partition 4.

As described above, since the plasma display panel is a device using discharge, cells must be formed so that discharge can occur well. Barrier barriers (BRRIER RIB) 4 for forming such discharge cells and enabling discharge are formed on the back substrate 1, and the MgO protective film 6 is formed on the upper electrode 7 disposed on the front substrate 8. Is formed.

The role of the MgO passivation layer 6 among the PDP components lowers the discharge voltage when the discharge occurs in the PDP, and serves to protect the electrodes 2 and 7 inside the panel.

In addition, the MgO passivation layer 6 is formed by forming a thin film mainly by sputtering, e-beam evaporation, or the like, and then patterning the MgO passivation layer 6. There is a limit to acting as a sufficient protect-layer and producing a secondary electron emission effect.

As described above, the Mg0 protective film 6 is very vulnerable to moisture as it comes into contact with the atmosphere despite the high secondary electron emission effect, so that the sputtering resistance is weak and the voltage (plasma discharge voltage) characteristics are poor. Unstable In addition, the absorption of moisture requires a heating and exhausting process, which makes the process complicated and has been pointed out as a significant problem in actual PDP display.

In order to solve the above problems, the present invention utilizes the advantages of MgO as it is and deposits a LaF ₃ thin film on the MgO thin film so that the uniform discharge and voltage characteristics are stabilized, and the brightness and luminance efficiency are improved. And the manufacturing method thereof.

1 is a schematic cross-sectional view of a general plasma display panel,

2 is a schematic cross-sectional view of a plasma display panel according to the present invention;

3 is a graph showing FT-IR (fouier transform infrared spectroscopy) measurements of a LaF ₃ thin film deposited on an MgO thin film on a Si wafer surface by a manufacturing method according to the present invention;

4 to 6 are diagrams illustrating discharge characteristics of respective voltages of a plasma display panel including a single layer MgO thin film and a LaF ₃ thin film deposited on the MgO thin film.

<Description of the symbols for the main parts of the drawings>

1. Back glass (sodaline glass) 2. Lower electrode (Ag)

3. Dielectric layer 4. Barrier rib

5. Phosphor layer 6. MgO protective film

7. Upper electrode 8. Front substrate

11. Back glass (sodaline glass) 12. Lower electrode (Ag)

13. Dielectric layer 14. Barrier rib

15. Phosphor layer 16. MgO protective film

16a. LaF ₃ thin film 17. Upper electrode

18. Front Board

In order to achieve the above object, the plasma display panel according to the present invention includes an upper electrode on a stripe in a direction crossing each other on opposite surfaces of the front substrate and the rear substrate, which are spaced apart at regular intervals by a partition wall and oppose each other; A plasma display panel having a lower electrode formed thereon, a dielectric layer covering the upper and lower electrodes and an MgO passivation layer on the dielectric layer of the front substrate, wherein the LaF ₃ thin film is formed on the MgO passivation layer of the front substrate. do.

The MgO protective film is formed to a thickness of 500nm or more, the LaF ₃ thin film is preferably formed of a thickness of 5 to 20nm.

In addition, in order to achieve the above object, the manufacturing method of the plasma display panel according to the present invention, the stripe in the direction crossing each other on the opposing surface of the front substrate and the rear substrate which are spaced apart at regular intervals by a partition wall and facing each other A method of manufacturing a plasma display panel having a top electrode and a bottom electrode formed thereon, a dielectric layer covering the top and bottom electrodes and a MgO passivation layer on the dielectric layer of the front substrate, wherein the LaF ₃ thin film is formed on the MgO passivation layer. It characterized by comprising; forming by an electron beam deposition method.

The deposition temperature of the LaF ₃ thin film is preferably the same as the deposition temperature of the MgO protective film.

Hereinafter, a method of manufacturing a plasma display panel according to the present invention will be described in detail with reference to the drawings.

2 is a schematic cross-sectional view of a plasma display panel according to the present invention.

A plasma display panel and a method of manufacturing the same according to the present invention are characterized by depositing a LaF ₃ thin film that suppresses a water absorption effect on an MgO protective film formed on a front substrate. That is, LaF ₃ thin films are deposited to reduce the influence of water, a fatal weakness of MgO thin films.

2, the plasma display panel according to the present invention includes discharge cells in which a space between the rear substrate 11 and the front substrate 18 facing each other is separated by a partition wall 14. do. The discharge cell is a plasma discharge space divided to correspond to each pixel by forming the partition 14 on the back substrate 11.

By discharging by the voltage applied through the lower electrode 12 and the upper electrode 17 formed in a stripe in the direction crossing each other on the opposite surface of the back substrate 11 and the front substrate 18 in such a discharge space The image will be displayed. The upper and lower electrodes 12 and 17 are respectively covered by the dielectric layers 13.

Such a PDP forms a partition 14 on the rear substrate 11 to create a plasma discharge space, thereby causing a discharge in the discharge space to display an image. The partition 14 is usually formed by screen printing, and should be formed to have a constant pattern. By doing in this way, the image by the discharge between adjacent cells can be clearly distinguished and viewed by the partition 14.

As described above, since the plasma display panel is a device using discharge, cells must be formed so that discharge can occur well. Barrier ribs 14 are formed on the rear substrate 11 and the MgO passivation layer 16 is formed on the upper electrode 17 disposed on the front substrate 18. At a thickness of 500 nm or more. On the MgO passivation film 16, a LaF ₃ thin film 16a, which characterizes the present invention, is formed by depositing a thin thickness of 5 to 20 nm.

That is, in the plasma display panel described above, MgO is deposited on the front substrate 18 because the discharging is a sustain discharge consisting of surface discharge.

As shown in FIG. 2, when the MgO thin film 16 is deposited on the dielectric layer 13 on the front substrate 18, impurities (moisture) on the surface, that is, Mg (OH) ₂ may affect the PDP panel. have. Moisture in these impurities causes fatal results for the MgO thin film 16. In addition, impurities (moisture) and the like in the atmosphere that will be present during and after deposition continue to degrade the performance of the PDP.

This degradation is presumably due to the formation of Mg (OH) _{2 in} which MgO and OH groups are bonded to the inside of the thin film. It is necessary to minimize the formation of such impurities (moisture) and improve the performance of the device. Of course, in the case of packaging the front and rear substrates 11 and 18 of the PDP, the heat treatment process is also performed by vacuum evacuation, but the sufficient heat treatment effect is not large in actual display elements.

Accordingly, the plasma display panel according to the present invention can be said to improve the performance of the device by performing the deposition process of the LaF ₃ thin film 16a on the MgO protective layer 16 on the front substrate 18.

The LaF ₃ thin film 16a makes it possible to minimize contact with air to the MgO protective film 16 when the front substrate 18 is manufactured and taken out of the evaporator on the surface of the MgO protective film 16. That is, the LaF ₃ thin film 16a serves to block the formation of impurities (moisture), thereby preventing the OH group from being formed on the MgO protective film 16.

This is because the LaF ₃ thin film 16a is insoluble in water. Usually, when the MgO protective film 16 is taken out of the evaporator and exposed to air, an OH group is formed on the surface of the MgO protective film 16 by about 5 to 20 nm thinly, so that the composition of the MgO does not match the original composition. Such a surface has disadvantages such as nonuniformity of discharge voltage and voltage rise in the manufacture of PDP.

Complementing this disadvantage is that the LaF ₃ thin film 16a is deposited on the MgO passivation film 16 at the same deposition temperature as the deposition temperature of the MgO passivation film 16 by the electron beam evaporation method. By blocking the bond between moisture and MgO, suppressing the formation of Mg (OH) ₂ inside the thin film, and fabricating a panel, during gas discharge, the LaF ₃ thin film 16a is sputtered to form an MgO protective film 16 on the dielectric layer 13. ) Will remain.

That is, the actual secondary electron emission is performed by the MgO protective film 16, so that secondary electron emission can be easily performed without the OH group bonded to the MgO surface. Therefore, uniform discharge and stable discharge effect can be expected.

3 is a graph showing the FT-IR measurement value of the LaF ₃ thin film deposited on the MgO thin film on the Si wafer surface by the manufacturing method according to the present invention.

In order to accurately see the OH group, MgO is deposited to a thickness of 500 nm or more using a Si substrate, and a thin film about 5 to 20 nm is deposited thereon. The FT-IR (fouier transform infrared spectroscopy) of FIG. As shown in Fig. 1, it can be seen that (Mg (OH) ₂ ) is not formed by the LaF ₃ thin film on the MgO protective film deposited on the Si substrate.

That is, the FT-IR is a device for detecting the presence or absence of a substance by detecting a unique frequency mode formed for every substance, and is mainly used for impurity detection. In the FT-IR of FIG. 3, a portion suddenly falling near the wavenumber of 3600 to 3700 cm ⁻¹ represents a vibration mode caused by the OH group, which indicates that water absorption is suppressed by the LaF ₃ thin film. Therefore, the effect of removing the impurities (Mg (OH) ₂ ) can be expected by the LaF ₃ thin film.

4 to 6 are diagrams illustrating discharge characteristics for respective voltages of the plasma display panel including the MgO passivation layer of the single layer and the LaF ₃ thin film deposited on the MgO passivation layer.

4 to 6, a plasma display panel includes a single layer of MgO protective film deposited on a dielectric layer of a front substrate and a LaF ₃ thin film deposited on a MgO protective film on a dielectric layer of a front substrate. Perform the discharge for each voltage of. Referring to FIG. 4, when a discharge voltage of 170 V is applied, the discharge having the LaF ₃ thin film deposited on the MgO protective film shows a more stable discharge characteristic than the site where the single layer MgO protective film is deposited. 5 to 6, even when a discharge voltage of 190V and 200V is applied, the discharge having the LaF ₃ thin film deposited on the MgO protective layer shows more stable discharge characteristics than the portion on which a single layer of the MgO protective layer is deposited. By depositing a thin LaF ₃ thin film on the MgO protective film to suppress moisture absorption, secondary electron emission is easily performed without OH group bonding on the MgO surface, resulting in uniform discharge and stable discharge effect. It can be seen that.

Or less, but to example will be described in detail an embodiment of the present invention, it was not limited to only the embodiment of the PDP according to the present invention, improving the electron-emitting characteristics by using the LaF ₃ thin film on a thin film to be the electron emitting structure that is Applicable to all flat panel display devices such as, FED, Plat CRT, etc.

<Example>

According to an embodiment of the present invention, an AC-type PDP in which a LaF ₃ thin film is sequentially deposited on an upper electrode, a dielectric layer, and an MgO passivation layer is formed on a front substrate, in a stripe shape in a direction crossing each other on each opposite surface of a rear substrate. to be.

The lower electrode Ag, the dielectric layer, and the partition wall on the stripe are formed on the rear substrate, and the phosphor layer is formed on the dielectric layer between the partition walls.

The lower electrode Ag, the dielectric layer, and the partition wall were formed by screen printing. The upper electrode was patterned after the ITO transparent electrode layer was deposited on the front substrate. The MgO protective film and LaF ₃ thin film are deposited by electron beam evaporation. In such a panel, only a gas discharge was formed without a phosphor layer with a gas of Ne-Xe. In addition, all conditions, such as a pressure of ^10-6 torr and an aging time (about 12 hours), were made the same. In addition, the discharge voltage was measured by sustain discharge, and the thin film was grown by adjusting the thickness of the MgO protective film to 5 nm at a pressure of 10 ⁻⁶ torr. The LaF ₃ thin film on the MgO protective film was deposited at a temperature equal to or higher than the deposition temperature of the MgO protective film with a thickness of 15 nm or more.

The front substrate and the back substrate manufactured as described above were sealed and bonded together, and exhausted by a vacuum heating and exhausting apparatus, and then the discharge characteristics of the panel were examined.

Comparative Example

Under the same conditions as in the above embodiment, the upper electrode, the dielectric layer, and the MgO protective film formed on the front substrate on the opposite surface of the rear substrate in the shape of stripes crossing each other were adjusted to 5 nm. Thereafter, the front substrate and the back substrate manufactured as described above were sealed and bonded together, and exhausted by a vacuum heating and exhausting apparatus, and then the discharge characteristics of the panel were examined.

As can be seen from Table 1, by depositing a LaF ₃ thin film for inhibiting moisture absorption on the MgO protective film of the front substrate, during the plasma discharge in the panel, on the MgO protective film than when a single layer of MgO protective film is formed It can be seen that the overall discharge voltage and the sustain discharge voltage are lower when the LaF ₃ thin film is deposited for moisture absorption inhibition. This requires a high discharge voltage when a single layer of MgO protective film is formed, whereas by forming a LaF ₃ film on the MgO protective film, moisture absorption of the MgO protective film is suppressed and impurities (Mg (OH) ₂ ) are removed to thereby remove the secondary. It can be seen that electron emission can be easily performed, and uniform discharge and stable discharge effects can be expected.

As described above, the plasma display panel and the method of manufacturing the same according to the present invention by depositing a LaF ₃ thin film on the MgO protective film formed thereon, Mg (OH) ₂ impurities in the MgO thin film is minimized to secondary The electron emission is improved, the plasma discharge inside the PDP cell is stabilized, and the voltage fluctuation is not severe. Therefore, the driving characteristics as the display element are improved, and the vacuum device for storage is not required. Therefore, image display characteristics and luminance efficiency are improved, and at the same time, the lifetime of the PDP is extended.

Claims (5)

A dielectric layer covering the upper and lower electrodes, the upper electrode and the lower electrode being formed on a stripe in a direction crossing each other on the opposing surfaces of the front substrate and the rear substrate, which are spaced apart at regular intervals by a partition wall, respectively; A plasma display panel having an MgO passivation layer on a dielectric layer of a front substrate. And a LaF ₃ thin film is formed on the MgO protective layer of the front substrate. The method of claim 1, And the MgO passivation layer is formed to a thickness of 500 nm or more. The method of claim 1, The LaF ₃ thin film is a plasma display panel, characterized in that formed in a thickness of 5 to 20nm. A dielectric layer covering the upper and lower electrodes, the upper electrode and the lower electrode being formed on a stripe in a direction crossing each other on the opposing surfaces of the front substrate and the rear substrate, which are spaced apart at regular intervals by a partition wall, respectively; In the method of manufacturing a plasma display panel provided with an MgO protective film on the dielectric layer of the front substrate, Forming a LaF ₃ thin film on the MgO protective film by electron beam deposition; and manufacturing a plasma display panel. The method of claim 4, wherein The deposition temperature of the LaF ₃ thin film is the same as the deposition temperature of the MgO protective film manufacturing method of the plasma display panel.