KR100786858B1 - Flat panel display device having reflective layer and manufacturing method of the reflective layer - Google Patents

Abstract

A flat panel display device having a reflective film, the flat panel display device comprising: a transparent first substrate; a second substrate connected to the first substrate to form a vacuum sealed container; an electron emission source emitting electrons on the second substrate; And a fluorescent surface that receives the electrons from one surface of the first substrate facing the second substrate and emits light, and a reflective film of metal positioned on the entire surface of the first substrate while covering the fluorescent surface, wherein the reflective film has electrons directed to the fluorescent surface. A number of fine holes are provided to facilitate passage. Therefore, the reflective film has an advantage of improving the brightness of the screen under the same driving voltage conditions by passing the electrons to the fluorescent surface more easily, or lowering the driving voltage of the flat panel display device under the conditions of the same brightness.

Flat panel display, field emission display device, reflective film, fluorescent film, fluorescent surface, brightness, driving voltage, aluminum film

Description

Flat panel display device having a reflective film and a manufacturing method of the reflective film {Flat panel display device having reflective layer and manufacturing method of the reflective layer}

1 is a partial cross-sectional view of a flat panel display device according to the present invention.

2 is a partially enlarged view of a reflective film according to the first embodiment of the present invention;

3 is a partially enlarged view of a reflective film according to a second embodiment of the present invention;

4 and 5 are schematic views for explaining the manufacturing process of the reflective film according to the first and second embodiments of the present invention.

6 is a partial cross-sectional view of an anode substrate among flat panel display apparatuses according to the prior art.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display device, and more particularly, to a flat panel display device having a metal reflective film on a surface of a fluorescent surface, and a manufacturing method of the reflective film.

In general, a flat panel display (FPD) is a substantially flat display device that is thin and relatively low voltage, unlike a cathode ray tube (CRT) that requires a large volume and a high voltage. The field emission display (FED) and the fluorescent fluorescence display (VFD) are examples of this.

Such a flat panel display device mainly includes an electron emission source on a cathode substrate to form a structure capable of emitting electrons, and an anode substrate disposed opposite to the cathode substrate to receive electrons and emit light, and a metal reflective film-representatively An aluminum film is formed to improve the brightness of the screen.

6 is a cross-sectional view of an anode substrate among flat panel display apparatuses according to the prior art, wherein the anode substrate 1 includes a transparent front substrate 3 and a plurality of red (R), green (G), and blue (B) fluorescent films ( 5) and a metal reflective film 9 covering the fluorescent surface 7, and optionally between each of the R, G, and B fluorescent films 5, a black matrix film (a light absorber); 11) This is located to improve the contrast of the screen.

Here, the reflective film 9 is applied with a voltage higher than the cathode substrate (not shown) to induce electrons toward the anode substrate 1, and when the electrons collide with the fluorescent surface 7, the electrons reflected toward the cathode substrate are used. It has a mirror function that reflects back to the direction, and the electrons are flown so as not to accumulate on the fluorescent surface 7 to increase the life of the fluorescent surface 7 and to prevent arcing between the two substrates.

In the manufacture of the reflective film 9, a known filming solution is generally applied to the entire front substrate 3 on the fluorescent surface 7 and dried to form a filming film (not shown), and a known vacuum deposition equipment. After depositing an aluminum film on the surface of the film film, and then firing the anode substrate 1 at a high temperature, the film forming material is evaporated through the fine pores of the aluminum film, the aluminum film on the fluorescent surface 7 as shown It is a process that remains.

A prior art related to such a flat panel display device having a metal reflective film is a method of manufacturing an aluminum film disclosed in US Pat. No. 6,126,988. This technique makes the aluminum film more flattened so that back scattering due to the surface roughness of the aluminum film is performed. It provides a technique to prevent scattering.

By the way, in order to fully exhibit the mirror effect, it is important that the reflecting film 9 is formed to an appropriate thickness (about 600 to 800 kPa). That is, if the reflective film 9 is formed too thin, it is difficult to re-reflect electrons reflected from the fluorescent surface 7, and if the reflective film 9 is formed too thick, electrons provided from the cathode substrate penetrate the reflective film 9. This is because it is difficult to reach the fluorescent screen 7 and the fluorescent screen 7 does not emit light with sufficient intensity.

However, even when the reflective film 9 is formed to an appropriate thickness, when the driving voltage of the display device is not sufficiently high, the problem that the electrons do not sufficiently pass through the reflective film 9, makes it difficult to reach the fluorescent surface.

In other words, in the case of a display device operating at a high voltage such as a cathode ray tube, a high voltage of approximately 25 to 30 kV is applied to the reflecting film 9, so that the electrons are sufficiently passed through the reflecting film 9 by the high voltage, and most of the fluorescent surface ( 7), but in the case of a conventional field emission display device, since a medium voltage of about 1 to 5 kV is applied to the reflective film 9, electrons do not sufficiently pass through the reflective film 9, and the fluorescent surface is blocked. The amount of electrons reaching (7) is significantly reduced.

As described above, in the flat panel display apparatus according to the prior art, since the reflective film 9 does not sufficiently provide electrons to the fluorescent screen 7, the luminance of the screen is lowered, and the flow of electrons in the reflective film 9 is not smooth and thus the fluorescent screen ( The life of 7) is shortened, and an arc occurs between two substrates, such that the function of the reflective film 9 itself is generally reduced.

Therefore, the present invention is to solve the above problems, the object of the present invention is to pass the electrons to the fluorescent surface smoothly to improve the brightness of the screen, the function of the reflection film itself, such as electron induction function and reflection function and fluorescent surface protection The present invention provides a flat panel display device and a method for manufacturing the reflective film, which can effectively exert the above effect.

In order to achieve the above object, the present invention,

A transparent first substrate, a second substrate connected to the first substrate to form a vacuum sealed container, an electron emission source emitting electrons on the second substrate, and a first substrate facing the second substrate. A fluorescent surface that receives the electrons from one surface and emits light, and a metal reflective film disposed on the front surface of the first substrate while covering the fluorescent surface, wherein the reflective film includes a plurality of fine holes for smoothly passing electrons to the fluorescent surface. Provided is a provided flat panel display device.

In addition, the present invention to achieve the above object,

Applying and drying a filming solution on the substrate on which the fluorescent surface is formed to form a filming film, and depositing aluminum on the filming film, patterning the deposited aluminum film to form a reflective film having a plurality of fine holes, and the substrate The present invention provides a method for manufacturing a reflective film of a flat panel display device, comprising evaporating a vaporized film forming material through micropores of the reflective film.

Preferably, the reflective film is formed by depositing aluminum on the film to form an aluminum film, forming a photoresist film on the aluminum film, and partially exposing and developing the photoresist film to form a plurality of fine holes in the photoresist film. Patterning and selectively removing a portion of the aluminum film exposed through the fine holes of the photoresist film with an etchant, and peeling and removing the remaining photoresist film.

Optionally, the forming of the reflective film includes forming a photoresist film on the film, and partially exposing and developing the photoresist film to form a plurality of lift-off layers, and depositing aluminum on the film and the lift-off layer. Forming an aluminum film, and selectively removing the lift-off layer and the aluminum film on the surface of the lift-off layer with an etchant.

As described above, the flat panel display apparatus according to the present invention, in which a plurality of fine holes are provided in the reflective film, facilitates the passage of the electrons through the reflective film, thereby increasing the amount of electrons provided to the fluorescent surface through the reflective film at the same driving voltage. It has the advantage of improving the brightness of the screen.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partial cross-sectional view of a flat panel display device according to an embodiment of the present invention, and more specifically, a field emission display device having a triode structure will be described as an example.

As shown, the field emission display device has a side where a first substrate (hereinafter referred to as "front substrate" 2) and a second substrate (hereinafter referred to as "back substrate" 4 for convenience) are not shown. It is integrally connected by glass to form a sealed container of vacuum, and the rear substrate 4 is configured to emit electrons by forming an electric field, and the front substrate 2 receives electrons to emit light to implement a predetermined image. A configuration is provided.

That is, for example, a plurality of cathode electrodes 6 are arranged in a stripe pattern on the rear substrate 4, and an insulating layer 8 having a plurality of holes 8a is disposed on the cathode electrodes 6 to a predetermined height. A plurality of gate electrodes 10 are formed in a predetermined pattern, for example, a stripe pattern vertically intersecting with the cathode electrode 6, on the insulating layer 8 except for the hole 8a. An emitter 12, which is an electron emission source, is provided on the cathode electrode 6 and into the holes 8a and 10a of the gate electrode 10 at a lower height than the insulating layer 8.

As a result, when a pulse voltage according to a driving signal is applied to the cathode electrode 6 and the gate electrode 10, a specific emitter 12 is formed by forming an electric field by a voltage difference between the cathode electrode 6 and the gate electrode 10. Electron emission takes place.

On the other hand, on one surface of the front substrate 2 facing the rear substrate 4, a fluorescent surface 16 composed of a plurality of R, G, B fluorescent films 14 is formed, and optionally R, G, A black matrix film 18 that is a light absorber is provided between the B fluorescent films 14. A reflective film 20 made of metal, typically aluminum, is formed on the entire front substrate 2 while covering the fluorescent surface 16, and a voltage for attracting electrons to the reflective film 20 (approximately, 1 to 5). kV) is applied.

Thus, electrons emitted from the emitter 12 impinge on the reflective film 20 across the vacuum sealed container by the voltage provided to the reflective film 20, and pass through the reflective film 20 to reach the fluorescent surface 16. As a result, the fluorescent screen 16 is excited to implement a predetermined image. In this case, the front substrate 2 is generally made of a transparent glass substrate for visible light transmission. In FIG. 1, reference numeral 22 denotes a spacer for keeping the cell gap of the field emission display device constant.

Here, the flat panel display device provided in this embodiment forms the reflective film 20 to an appropriate thickness (approximately 600 to 800 kPa) so that the reflective film 20 can sufficiently exhibit a mirror effect, and at the same time, , 1-5 kV) to provide a plurality of fine holes 20a in the reflective film 20 so that electrons can smoothly escape the reflective film 20 and reach a fluorescent surface.

2 is a partially enlarged view of a reflective film according to the first embodiment of the present invention, in which the plurality of fine holes 20a having a circular shape are formed. Preferably, the diameter D of each of the micro holes 20a may be set to 3 to 50 μm, and the horizontal and vertical gaps G1 and G2 between the respective micro holes may be set to 3 to 1,000 μm.

3 is a partially enlarged view of a reflective film according to the second embodiment of the present invention, wherein the reflective film 20 is formed with a plurality of fine holes 20a formed in a quadrangle. The vertical widths W and H may be set to 3 to 50 µm, respectively, and the horizontal and vertical gaps G1 and G2 of the micro holes 20a may be set to 3 to 1,000 µm, respectively.

The micro holes 20a provided in the reflective film 20 may be manufactured in various shapes such as polygons in addition to the above-mentioned circles and quadrangles, and the size and spacing of each micro hole 20a are not limited to the above-described embodiment. However, the fine holes 20a may be uniformly distributed at the same intervals so that electrons pass through the entire reflective film 20 more easily.

In addition, it is preferable that the reflecting film 20 sets the total area ratio of the plurality of micro holes 20a per unit area to 10 to 70% or less so that the mirror function deterioration due to the micro holes 20a does not occur.

As described above, the reflective film 20 having the fine holes 20a increases the luminance of the screen at the same driving voltage as compared with the conventional reflective film structure by allowing a larger amount of electrons to reach the fluorescent surface 16, or It is possible to effectively lower the driving voltage while realizing the luminance.

Next, the manufacturing method of the reflective film by this invention is demonstrated.                     

4 is a schematic diagram illustrating a manufacturing process of a reflective film according to a first embodiment of the present invention. First, a front substrate 2 having a fluorescent surface 16 is prepared, and a known filming solution is formed on the fluorescent surface 16. Is applied and dried to form a filming film 24. (See FIG. 4A) The filming film 24 serves to alleviate the unevenness of the aluminum film to be manufactured thereafter, thereby increasing the reflection efficiency of the aluminum film.

Then, aluminum is deposited on the peeling film 24 by using a vacuum deposition apparatus, which is known, to form an aluminum film 26 as a reflective film, and a known photoresist film (see FIG. 4B) is formed on the aluminum film 26. 28). (See FIG. 4C) Next, the photoresist film 28 is partially exposed and developed using an exposure mask (not shown), and a plurality of fine holes 28a are formed in the photoresist film 28 as shown in FIG. 4D. Pattern.

When the etching solution is sprayed onto the patterned photoresist film 28, a portion of the aluminum film 26 exposed through the fine holes 28a of the photoresist film 28 is selectively removed to remove the aluminum film 26. ), A plurality of fine holes 26a are patterned. (See Figure 4e)

Finally, the remaining photoresist film 28 is removed by a peeling process (see FIG. 4F), and the front substrate 2 is baked for about 10 to 30 minutes in a 400 to 500 ° C. atmosphere to form the filming film 24. The material is evaporated through the micropores of the aluminum film 26 to complete the aluminum film 26 having a plurality of holes 26a as shown in FIG. 4G.

FIG. 5 is a schematic diagram illustrating a manufacturing process of a reflective film according to a second embodiment of the present invention. First, a front substrate 2 having a fluorescent surface 16 is formed in the same manner as in the previous embodiment, and the fluorescent surface 16 The filming film 24 is formed on it. (See Figure 5A)

A well-known photoresist film 30 is formed on the filming film 24, and the photoresist film 30 is partially exposed and developed using an exposure mask (not shown) (see FIG. 5B), and the photoresist film 30 shown in FIG. Patterned into multiple lift-off layers 32 as shown. At this time, the lift-off layer 32 is formed in the same shape as the fine holes of the aluminum film to be formed later.

Next, an aluminum film 26 is formed by depositing aluminum so that the lift-off layer 32 is sufficiently covered on the peeling film 24 and the lift-off layer 32 using a known vacuum deposition equipment. (See FIG. 5D) an etching solution is sprayed onto the front substrate 2 to selectively remove the lift-off layer 32 and the aluminum film 26 on the surface of the lift-off layer 32 to thereby remove the aluminum film 26. ), A plurality of fine holes 26a are patterned. (See Figure 5E)

Finally, the process of removing the filming film 24 by firing the front substrate 2 is performed in the same manner as in the previous embodiment, and as shown in FIG. 5F, the aluminum film having a plurality of fine holes 26a patterned therein. (26) That is, the reflective film is completed.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

 As described above, the present invention can more easily pass electrons emitted from the emitter to the fluorescent surface by patterning a plurality of fine holes in the reflective film applied to the flat panel display device. Accordingly, the present invention effectively improves the brightness of the screen at the same driving voltage as before, or lowers the driving voltage of the flat panel display device under the condition of implementing the same brightness.

Claims (5)

A transparent first substrate; A second substrate connected to the first substrate to form a vacuum sealed container; An electron emission source emitting electrons on the second substrate; A fluorescent surface provided on one surface of the first substrate facing the second substrate and provided with a plurality of fluorescent films to emit electrons; And A metal reflective film disposed on the front surface of the first substrate while covering the entire fluorescent surface and maintaining a single potential; The reflective film is provided with a plurality of fine holes to facilitate the passage of electrons to the fluorescent surface. Forming a filming film by applying and drying a filming solution on a substrate on which a fluorescent surface having a plurality of fluorescent films is formed; In addition to depositing aluminum on the film, the patterned aluminum film is formed to form a reflective film having a plurality of fine holes; Firing the substrate to evaporate the peeling film forming material through the micropores of the reflective film, And the reflective film is formed to cover the entire fluorescent surface and maintains a single electric potential. The method of claim 2, Formation of the reflective film, Depositing aluminum on the film to form an aluminum film; Forming a photoresist film on the aluminum film; Partially exposing and developing the photoresist film to pattern a plurality of fine holes in the photoresist film; Selectively removing a portion of the aluminum film exposed through the fine holes of the photoresist film with an etchant; A method for manufacturing a reflective film of a flat panel display device comprising peeling and removing the remaining photoresist film. The method of claim 2, Formation of the reflective film, Forming a photoresist film on the film; Partially exposing and developing the photoresist film to form a plurality of lift-off layers; Depositing aluminum on the film and the lift-off layer to form an aluminum film; And selectively removing the lift-off layer and the aluminum film on the surface of the lift-off layer with an etching solution. The method of claim 4, wherein And the lift-off layer has the same shape as that of the fine holes of the reflective film.

Images