JP2003242893A - Plasma display device and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display device and a method for manufacturing the plasma display device which can flatten a dielectric layer irrespective of a step of sustaining electrodes and/or a bus electrode, provide a dielectric layer of small film thickness and excellent dielectric characteristic, suppress the electrostatic capacity between the sustaining electrodes, and realize excellent reliability, highly fine and large screen. <P>SOLUTION: This plasma display device comprises a first panel 10 with a plurality of pairs of discharge sustaining electrodes 12, and a dielectric layer 14 to cover the discharge sustaining electrodes 12 formed inside thereof, and a second panel 20 which is adhered to the inside of the first panel 10 so as to form a discharge space 4. The dielectric layer 14 a flattened dielectric film 14a to cover the discharge sustaining electrodes 12 and the bus electrode 13, and a high withstand voltage dielectric film 14b which covers the flattened dielectric film 14a and has more excellent withstand voltage characteristic than that of the flattened dielectric film 14a. The flattened dielectric film 14a is a glass film of low melting point formed by a paste method, and the high withstand voltage dielectric film 14b is a silicon oxide film formed by a sputtering method, a vapor deposition method, or a chemical vapor deposition method. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device suitable for a large screen and high miniaturization and a manufacturing method thereof.

[0002]

2. Description of the Related Art Various flat panel display devices have been studied as an image display device to replace a cathode ray tube (CRT) which is currently the mainstream. A liquid crystal display device (LCD), an electroluminescence display device (ELD), and a plasma display device (PDP: plasma display) can be exemplified as such a flat display device. Among them, the plasma display device has advantages such as relatively easy enlargement of a screen and widening of a viewing angle, excellent resistance to environmental factors such as temperature, magnetism, and vibration, and long life, It is expected to be applied to large-scale information terminal devices for public use as well as household wall-mounted televisions.

A plasma display device is disclosed in, for example, Japanese Patent Laid-Open No. 7-
As disclosed in JP-A-220641, a voltage is applied to a discharge cell in which a discharge gas composed of a rare gas is sealed in a discharge space, and ultraviolet rays generated by glow discharge in the discharge gas generate a phosphor in the discharge cell. A display device which emits light by exciting a layer. That is, the individual discharge cells are driven by a principle similar to that of a fluorescent lamp, and the discharge cells are usually assembled on the order of hundreds of thousands to form one display screen. The plasma display device is a direct current drive type (DC type) or an alternating current drive type (AC type) depending on a method of applying a voltage to a discharge cell.
They are roughly divided into two types, each with advantages and disadvantages.

The AC type plasma display device is suitable for high definition because the rib ribs for partitioning the individual discharge cells in the display screen may be formed in stripes, for example. Moreover, since the surface of the electrode for discharging is covered with the dielectric layer, the electrode has advantages that it is hard to wear and has a long life.

In the currently commercialized AC type plasma display device, on the sustain electrode formed on the inner surface of the first substrate,
A dielectric layer is formed, and the dielectric layer is usually composed of a paste-printed and fired low melting point glass film. In the AC type plasma display device, charges are accumulated on the surface of the dielectric layer, and a reverse voltage is applied to the sustain electrodes, whereby the accumulated charges are discharged and plasma is generated. Since the sustain electrode is generally formed of a transparent electrode, a bus electrode made of a metal electrode is laminated on the sustain electrode in the longitudinal direction in order to reduce the resistance of the sustain electrode.

By the way, in this main plasma display device, demands for higher density and higher definition of pixels and low voltage driving are increasing more and more. When the density of pixels is increased, the widths of the sustain electrodes and the bus electrodes have to be reduced due to space restrictions, and as a result, the resistance value increases.
Particularly in a large-area plasma display device, the increase in resistance value is remarkable. When the resistance value of the sustain electrode increases, the time constant τ = R × C (R is resistance and C is capacitance) increases at the end portion of the sustain electrode, and the applied voltage waveform collapses. Specifically, the rise time of the voltage pulse becomes long. As a result, an image becomes non-uniform at both ends of the screen of the plasma display device. In order to suppress this, it is effective to reduce the capacitance between the sustain electrodes.

A dielectric layer formed by a paste printing method in a conventional plasma display device has a dielectric constant higher than that of a silicon oxide film formed by a sputtering method, an evaporation method, a CVD (chemical vapor deposition) method or the like. The rate is large (ε = 8
.About.12), and is formed thicker than 20 .mu.m in order to improve withstand voltage characteristics. However, as mentioned above,
To increase the density and definition of pixels, it is effective to reduce the capacitance between the sustain electrodes. That is, it is effective to reduce the film thickness and relative permittivity of the dielectric layer. Since a silicon oxide film formed by a sputtering method or a CVD method has a low dielectric constant and a high withstand voltage, the film thickness can be made smaller than that of a conventional film. Therefore, there has been proposed a method of forming a dielectric layer in a plasma display device by a thin film forming method such as a sputtering method, a vapor deposition method or a CVD method.

[0008]

However, in a conventional plasma display device in which a dielectric layer made of a silicon oxide film is formed by a thin film forming method such as a sputtering method, an evaporation method, a CVD method, etc. Moreover, it is difficult to flatten the surface of the dielectric layer. That is, these methods
The shape of the base is directly reflected on the shape of the film surface. Therefore, the dielectric film formed on the surface of the bus electrode has a step that directly reflects the step shape of the bus electrode. In this step portion of the dielectric film, due to its shape, a portion where the insulating property is insufficient is likely to occur, which becomes a cause of impairing the reliability of the plasma display device. For example, abnormal discharge may occur between the step portion of the bus electrode and the address electrode.

As disclosed in Japanese Unexamined Patent Publication No. 11-54051, a dielectric layer composed of a multilayer film has been proposed, but the dielectric layer is not sufficiently flattened and the withstand voltage characteristic and There has been a demand for a plasma display device that is highly reliable and suitable for high resolution and large screens.

The present invention has been made in view of such circumstances, and an object of the present invention is to flatten the dielectric layer regardless of the step difference of the sustain electrode and / or the bus electrode, and to reduce the thickness of the dielectric layer. To provide a plasma display device that realizes a dielectric layer with excellent voltage characteristics, suppresses electrostatic capacitance between sustain electrodes, is highly reliable, and is suitable for high miniaturization and large screens, and a manufacturing method thereof. is there.

[0011]

In order to achieve the above object, in the plasma display device according to the present invention, a plurality of pairs of discharge sustaining electrodes and a dielectric layer covering the discharge sustaining electrodes are formed inside. A first panel and a second panel that is attached to form a discharge space inside the first panel.
A high dielectric strength film having a panel, wherein the dielectric layer covers the discharge sustaining electrode, and a flattening dielectric film that covers the flattening dielectric film and is superior in withstand voltage characteristics to the flattening dielectric film. And a dielectric film.

According to the present invention, even if there is a step in the sustain electrode and / or the bus electrode, it is flattened by the flattening dielectric film. A high withstand voltage dielectric film having excellent withstand voltage characteristics is formed on the flat film. for that reason,
The surface of the high voltage dielectric film is also flat. As a result, abnormal discharge that occurs due to the presence of steps in the dielectric layer is suppressed.

Further, since the high withstand voltage dielectric film has excellent withstand voltage characteristics, the dielectric film can be made thin, and as a result, the total thickness of the dielectric layer is smaller than that of the conventional one. It can be reduced (for example, to about 20 μm or less). As a result, the capacitance between the discharge sustaining electrodes can be reduced, and the current for charging / discharging the discharge sustaining electrodes is reduced. When the current for charging / discharging is reduced, it is possible to make the discharge uniform even on a large screen and reduce the load on the drive circuit. Therefore, it contributes to higher resolution and larger screen of the plasma display device.

Preferably, the dielectric constant of the high withstand voltage dielectric film is smaller than 5. More preferably, the dielectric constant of the high withstand voltage dielectric film is smaller than 4. The lower limit is 1
The above is preferable. If the relative dielectric constant of the dielectric film is too high, it tends to be difficult to reduce the capacitance between the discharge sustaining electrodes, and if it is too low, the withstand voltage characteristics tend to deteriorate.

Preferably, the high withstand voltage dielectric film is a silicon oxide film. A silicon oxide film is preferable because it has a lower relative dielectric constant than a low melting point glass film formed by a paste method and easily reduces the capacitance between the discharge sustaining electrodes.

Preferably, the high withstand voltage dielectric film is formed by sputtering, vapor deposition or chemical vapor deposition. A silicon oxide film formed by such a method has a lower relative dielectric constant than a low melting point glass film formed by a paste method and is easy to reduce the capacitance between the discharge sustaining electrodes, which is preferable.

Preferably, the flattening dielectric film is a low melting point glass film. This low melting point glass film can be formed by a paste method or a dry film method,
It is possible to flatten the step due to the discharge sustaining electrode and / or the bus electrode.

Preferably, the flattening dielectric film has a film thickness of 3 to 10 μm, and the high withstand voltage dielectric film has a film thickness of 3 μm.
10 to 10 μm. If the film thickness of the flattening dielectric film is too thin, it is difficult to flatten it, and if it is too thick, the total capacitance tends to increase. Further, if the high withstand voltage dielectric film is too thin, the withstand voltage characteristic tends to be insufficient, and if it is too thick, the total capacitance tends to increase.

In the present invention, when each discharge sustaining electrode is a transparent electrode and a bus electrode having a resistance lower than that of the discharge sustaining electrode is formed on each discharge sustaining electrode, a step due to the bus electrode is a problem. become. Therefore, the structure of the present invention is
The effect is great in the plasma display device of the type in which the bus electrode is formed.

Preferably, the discharge sustaining electrode is formed in a strip shape along the longitudinal direction of the bus electrode, and each pixel has an island-shaped transparent electrode. By making the transparent discharge sustain electrodes island-shaped, the electrode area can be reduced, and as a result, the electrostatic capacitance between the discharge sustain electrodes can be further reduced, and the image quality at both edges of the display screen can be reduced accordingly. Non-uniformity can be reduced. In addition, the load on the drive circuit can be reduced, and a display device having such a large area can be realized.

The plasma display device of the present invention is an AC drive type plasma display device, and inside the second panel, there are address electrodes, barrier ribs partitioning the discharge space, and fluorescent light disposed between the barrier ribs. The body layer is preferably formed.

In the method of manufacturing a plasma display device according to the present invention, a plurality of pairs of discharge sustaining electrodes are formed inside the first panel, and a flattening dielectric film is formed to cover the discharge sustaining electrodes. A step of forming inside of one panel, and forming a high withstand voltage dielectric film having a withstand voltage characteristic superior to that of the above flattening dielectric film inside the first panel so as to cover the flattening dielectric film. And a step of laminating the second panel so that a discharge space is formed inside the first panel.

Preferably, the flattened dielectric film is formed by a paste coating method, and the high withstand voltage dielectric film is formed by a sputtering method, a vapor deposition method, or a chemical vapor deposition method. According to the method of manufacturing the plasma display device of the present invention, the plasma display device of the present invention can be easily manufactured.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on the embodiments shown in the drawings. 1 is a schematic cross-sectional view of a main part of a plasma display device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the main part taken along line II-II shown in FIG. 1, and FIG. 4 and 5 are schematic plan views of relevant parts showing the relationship between the discharge sustaining electrodes and the partition walls according to another embodiment of the present invention.

Overall Configuration of Plasma Display Device First, the overall configuration of an AC drive type (AC) type plasma display device (hereinafter may be simply referred to as a plasma display device) will be described with reference to FIG.

The AC type plasma display device 2 shown in FIG.
It belongs to a so-called three-electrode type, and discharge is generated between the pair of discharge sustaining electrodes 12. This AC type plasma display device 2 is formed by laminating a first panel 10 corresponding to a front panel and a second panel 20 corresponding to a rear panel. The light emission of the phosphor layers 25R, 25G, 25B on the second panel 20 is observed through the first panel 10. That is,
The first panel 10 is the display surface side.

The first panel 10 comprises a transparent first substrate 11
And a plurality of pairs of discharge sustaining electrodes 12 made of a transparent conductive material, which are provided in a stripe shape on the first substrate 11 substantially parallel to each other in the first direction X, and to reduce the impedance of the discharge sustaining electrodes 12. Provided on the discharge sustaining electrode 12
A bus electrode 13 made of a material having a lower electrical resistivity than
The dielectric layer 14 is formed on the first substrate 11 including the bus electrodes 13 and the discharge sustaining electrodes 12, and the protective layer 15 is formed thereon. The protective layer 1
5 does not necessarily have to be formed, but is preferably formed.

On the other hand, the second panel 20 includes a second substrate 21.
And a plurality of address electrodes (also referred to as data electrodes) 22 provided in stripes on the second substrate 21 along the second direction Y (substantially perpendicular to the first direction X) and substantially parallel to each other.
An insulator film 23 formed on the second substrate 21 including the address electrodes 22, an insulating partition rib 24 formed on the insulator film 23, and a partition rib 24 from the insulator film 23.
And a phosphor layer provided over the side wall surface of the. The phosphor layer is composed of a red phosphor layer 25R, a green phosphor layer 25G, and a blue phosphor layer 25B.

FIG. 1 is a partially exploded perspective view of the display device. Actually, as shown in FIG. 2, the top of the partition rib 24 on the second panel 20 side is in the third direction Z (first direction X). And in a direction orthogonal to the second direction Y), and abuts on the protective layer 15 on the first panel 10 side. Discharge gap W1 (see FIG. 3)
The region where the pair of discharge sustaining electrodes 12 for forming the electrodes and the address electrode 22 overlap corresponds to a single discharge cell. Then, a discharge gas is enclosed in the discharge space 4 surrounded by the barrier ribs 24 on which the phosphor layers 25R, 25G, 25B are formed and the protective layer 15. The first panel 10 and the second panel 20 have their peripheral portions,
It is joined using frit glass. The discharge gas sealed in the discharge space 4 is not particularly limited,
An inert gas such as xenon (Xe) gas, neon (Ne) gas, helium (He) gas, argon (Ar) gas, nitrogen (N ₂ ) gas, or a mixed gas of these inert gases is used. The total pressure of the enclosed discharge gas is not particularly limited, but is 6 × 10 ³ Pa to 8 × 10 ⁴
It is about Pa.

The direction in which the projected image of the discharge sustaining electrode 12 extends and the direction in which the projected image of the address electrode 22 extends are substantially orthogonal (though not necessarily orthogonal). As shown in FIG. 3, a pair of discharge sustaining electrodes 12 forming a discharge gap W1 and phosphor layers 25R, 25G, 2 emitting three primary colors.
An area where one set of 5B overlaps is one pixel (1 pixel) P
Equivalent to 1. Since the glow discharge is generated between the pair of discharge sustaining electrodes 12 forming the discharge gap W1, this type of plasma display device is called a "surface discharge type".
The driving method of this plasma display device will be described later.

The plasma display device 2 of the present embodiment is a so-called reflection type plasma display device, and includes a phosphor layer 25R,
Since the light emission of 25G and 25B is observed through the first panel 10, the conductive material forming the address electrode 22 may be transparent or opaque.
The conductive material forming 2 must be transparent. The transparency / opacity described here is based on the light transmittance of the conductive material in the emission wavelength (visible light region) peculiar to the phosphor layer material. That is, if it is transparent to the light emitted from the phosphor layer, it can be said that the conductive material forming the discharge sustaining electrodes and the address electrodes is transparent.

As the opaque conductive material, Ni, Al,
Au, Ag, Pd / Ag, Cr, Ta, Cu, Ba, L
Materials such as aB ₆ , Ca _0.2 La _0.8 CrO _{3 and the} like can be used alone or in combination. As a transparent conductive material, ITO (indium tin oxide)
And SnO ₂ . The discharge sustaining electrode 12 or the address electrode 22 can be formed by a sputtering method, a vapor deposition method, a screen printing method, a plating method, or the like.
Pattern processing is performed by a photolithography method, a sandblast method, a lift-off method, or the like.

The dielectric layer 14 formed on the surface of the discharge sustaining electrode 12 is, as shown in FIG. 2, a flattened dielectric film 14a which covers the discharge sustaining electrode 12 and the bus electrode 13 from the inside.
And a high withstand voltage dielectric film 14b covering the flattening dielectric film 14a from the inside. A protective film 15 is formed inside the high withstand voltage dielectric film 14b.

In this embodiment, the flattening dielectric film 14a is made of, for example, a low melting point glass film. The dielectric film 14a can be formed by a paste method or a dry film method. The paste method is a method in which a dielectric paste in which dielectric particles are dispersed in an organic solvent or a dispersion is applied to the surface of an object and then baked to form a film. The dry film method is a method in which a dielectric paste agent having a predetermined thickness is applied onto an organic film and a sheet-shaped dry film is transferred onto the surface of an object and then baked to form a film.

The flattening dielectric film 14a is formed on the inner surface of the first substrate 11 on which the discharge sustaining electrodes 12 and the bus electrodes 13 are formed.
By forming the step, the step is covered by the bus electrode 13 without being reflected by the dielectric film 14a, and the surface of the dielectric film 14a becomes flat.

In this embodiment, the high withstand voltage dielectric film 14b is used.
Is composed of a silicon oxide film. This silicon oxide film is formed by, for example, a sputtering method, a vapor deposition method, a CVD method or the like. When a film is formed by a sputtering method, a vapor deposition method, a CVD method, or the like, a film having a surface shape that conforms to the level difference of the base is obtained. The surface of the withstand voltage dielectric film 14b is also flat.

The film thickness (thickness from the discharge sustaining electrode 12 or the bus electrode 13 to the surface of the dielectric film 14a) T1 of the flattening dielectric film 14a is 3 to 10 μm, which is equal to that of the high withstand voltage dielectric film 14b. The film thickness T2 is 3 to 10 μm, and the total thickness thereof, that is, the thickness T0 of the dielectric layer 14 is 6 to 20 μm.

By providing the dielectric layer 14, the ions and electrons generated in the discharge space 4 are prevented from being discharged.
Direct contact with can be prevented. As a result, wear of the discharge sustaining electrode 12 can be prevented. The dielectric layer 14 has a memory function of accumulating wall charges generated in the address period and maintaining a discharge state, and a function of a resistor that limits an excessive discharge current.

The protective layer 15 formed on the surface of the dielectric layer 14 on the discharge space side has a function of protecting the dielectric layer 14 and preventing direct contact between ions and electrons and the discharge sustaining electrode. As a result, abrasion of the sustaining electrode 12 and the dielectric layer 14 can be effectively prevented. In addition, the protective layer 15
Also has a function of emitting secondary electrons necessary for discharging. As a material forming the protective layer 15, magnesium oxide (M
Examples thereof include gO), magnesium fluoride (MgF ₂ ), and calcium fluoride (CaF ₂ ). Among them, magnesium oxide is a suitable material having features such as chemical stability, a low sputtering rate, a high light transmittance at the emission wavelength of the phosphor layer, and a low discharge starting voltage. The protective layer 15 may have a laminated film structure composed of at least two kinds of materials selected from the group consisting of these materials.

As a constituent material of the first substrate 11 and the second substrate 21, high strain point glass and soda glass (Na ₂ O.C) are used.
aO ・ SiO ₂ ), borosilicate glass (Na ₂ O ・ B ₂ O ₃
・ SiO ₂ ), forsterite (2MgO ・ Si
O _2), can be exemplified lead glass _{(Na 2 O · PbO · SiO} 2). The constituent materials of the first substrate 11 and the second substrate 21 may be the same or different, but it is desirable that they have the same coefficient of thermal expansion.

The phosphor layers 25R, 25G, 25B are, for example, phosphors selected from the group consisting of a phosphor layer material that emits red light, a phosphor layer material that emits green light, and a phosphor layer material that emits blue light. It is made of a layer material and is provided above the address electrode 22. When the plasma display device is a color display, specifically, for example, a phosphor layer (red phosphor layer 25R) made of a phosphor layer material that emits red light is provided above the address electrode 22 to display a green color. A phosphor layer (green phosphor layer 25G) composed of a phosphor layer material that emits light is provided above another address electrode 22, and a phosphor layer composed of a phosphor layer material that emits blue light (blue phosphor). Body layer 25B) is further address electrode 2
2 is provided above, and one set of phosphor layers that emit these three primary colors is provided in a predetermined order. Then, as described above, the pair of discharge sustaining electrodes 1
2 and a set of phosphor layers 25 that emit these three primary colors
An area where R, 25G, and 25B overlap corresponds to one pixel P1.

As the phosphor layer material forming the phosphor layers 25R, 25G and 25B, a phosphor layer material having a high quantum efficiency and a low saturation with respect to vacuum ultraviolet rays is appropriately selected from conventionally known phosphor layer materials. Can be used. In the case of color display, the color purity is close to the three primary colors specified by NTSC, the white balance is good when the three primary colors are mixed, the afterglow time is short, and the afterglow times of the three primary colors are almost equal. It is preferred to combine the layer materials.

Specific examples of the phosphor layer material are shown below.
For example, as a phosphor layer material that emits red light, (Y_TwoO
_Three: Eu), (YBO_ThreeEu), (YVO_Four: Eu),
(Y _0.96P_0.60V_0.40O_Four: E
u_0.04), [(Y, Gd) BO_Three: Eu], (Gd
BO_Three: Eu), (ScBO_Three: Eu), (3.5Mg
O ・ 0.5MgF_Two・ GeO_Two: Mn), emits green light
As a phosphor layer material for_Two: Mn), (B
aA1₁₂O₁₉: Mn), (BaMg_TwoA1₁₆O
₂₇: Mn), (MgGa_TwoO_Four: Mn), (YB
O_Three: Tb), (LuBO_Three: Tb), (Sr_FourSi_Three
O₈Cl_Four: Eu), as a phosphor layer material that emits blue light
, (Y_TwoSiO₅: Ce), (CaWO_Four: Pb),
CaWO_Four, YP_0.85V_0.15O_Four, (BaMg
A1₁₄O₂₃: Eu), (Sr_TwoP_TwoO₇: Eu),
(Sr_TwoP_TwoO₇: Sn) and the like.

As a method of forming the phosphor layers 25R, 25G, 25B, a thick film printing method, a method of spraying phosphor layer particles, an adhesive substance is attached in advance to the site where the phosphor layer is to be formed, and the phosphor layer is formed. A method of attaching particles, a method of using a photosensitive phosphor layer paste, patterning the phosphor layer by exposure and development, and a method of forming a phosphor layer on the entire surface and then removing unnecessary portions by sandblasting You can

The phosphor layers 25R, 25G and 25B may be directly formed on the address electrode 22, or
It may be formed over the address electrode 22 and the side wall surface of the partition rib 24. Alternatively, the phosphor layer 25
R, 25G, and 25B may be formed on the insulator film 23 provided on the address electrode 22, or the rib rib 2 may be formed on the insulator film 23 provided on the address electrode 22.
It may be formed over the side wall surface of No. 4. Furthermore,
The phosphor layers 25R, 25G, 25B may be formed only on the side wall surfaces of the partition ribs 24. Examples of the constituent material of the insulator film 23 include low melting point glass and SiO ₂ .

In this embodiment, each pair of discharge sustaining electrodes 12 is used.
The discharge gap W1 between them is not particularly limited, but is preferably 1 to 150 μm, and more preferably 5 to 50 μm.
m, and more preferably 5 to 40 μm. Further, the insulation distance W2 between the pair of discharge sustaining electrodes and the other pair of discharge sustaining electrodes is 1.5 times larger than the discharge gap W1.

The electrode width of the discharge sustaining electrode 12 is not particularly limited, but is about 200 to 400 μm. Also, FIG.
The width of the address electrode 22 shown in is, for example, 50 to 100.
It is about μm.

The bus electrode 13 is typically a metallic material,
For example, Ag, Au, Al, Ni, Cu, Mo, Cr
It can be composed of a single layer metal film such as or a laminated film of Cr / Cu / Cr or the like. In the reflection type plasma display device, the bus electrode 13 made of such a metal material reduces the amount of visible light that is emitted from the phosphor layer and passes through the first substrate 11 to reduce the brightness of the display screen. Therefore, it is preferable to form the discharge sustaining electrode as thinly as possible within the range in which the required electric resistance value can be obtained. Specifically, the electrode width of the bus electrode 13 is smaller than the electrode width of the discharge sustaining electrode 12, and is, for example, about 30 to 200 μm. The bus electrode 13 can be formed by the same method as the discharge sustaining electrode 12 and the like.

As the constituent material of the partition rib 24, a conventionally known insulating material can be used, for example, a widely used low melting point glass mixed with a metal oxide such as alumina can be used. The partition ribs 24 have a width of about 50 μm or less and a height of 50 to 200 μm.
It is a degree. The pitch interval between the partition ribs 24 is, for example, about 50 to 400 μm.

A discharge gas consisting of a mixed gas is enclosed in the discharge space surrounded by the ribs 24.
The phosphor layers 25R, 25G, 25B emit light by being irradiated with ultraviolet rays generated based on the AC glow discharge generated in the discharge gas in the discharge space 4.

Manufacturing Method of Plasma Display Device Next, a manufacturing method of the plasma display device according to the embodiment of the present invention will be described. The first panel 10 can be manufactured by the following method. First, an ITO layer is formed on the entire surface of the first substrate 11 made of high strain point glass or soda glass by, for example, a sputtering method, and the ITO layer is patterned into stripes by a photolithography technique and an etching technique to maintain a pair of discharges. A plurality of electrodes 12 are formed. The main electrode portion 12a of the discharge sustaining electrode 12 extends in the first direction X.

Next, an aluminum film is formed on the entire inner surface of the first substrate 11 by, for example, a vapor deposition method, and the aluminum film is patterned by a photolithography technique and an etching technique, whereby each discharge sustaining electrode 12 is formed.
The bus electrodes 13 are formed along the edges of the. After that, a flattening dielectric film 14a and a high withstand voltage dielectric film 14b are formed on the entire inner surface of the first substrate 11 on which the bus electrodes 13 are formed. These film forming methods are as described above.

Next, a protective layer 15 made of magnesium oxide (MgO) and having a thickness of 0.6 μm is formed on the dielectric layer 14 by an electron beam evaporation method or a sputtering method. The first panel 10 can be completed through the above steps.

The second panel 20 is manufactured by the following method. First, the second made of high strain point glass and soda glass
An address electrode 22 is formed by forming an aluminum film on the substrate 21 of, for example, by a vapor deposition method and patterning it by a photolithography technique and an etching technique. The address electrode 22 extends in a second direction Y that is orthogonal to the first direction X. Next, a low melting point glass paste layer is formed on the entire surface by screen printing, and the low melting point glass paste layer is baked to form the insulator film 23.

Thereafter, partition ribs 24 are formed on the insulating film 23 so as to form a stripe pattern. The forming method at this time is not particularly limited, and examples thereof include a screen printing method, a sandblast method, a dry film method, and a photosensitive method. The dry film method is to laminate a photosensitive film on a substrate, remove the photosensitive film at the partition rib formation planned site by exposure and development, embed the partition rib forming material in the opening created by the removal, and burn. Is the way to do it. The photosensitive film is burned and removed by firing, and the partition rib forming material embedded in the openings remains to form partition ribs 24. The photosensitive method is a method in which a material layer for forming partition ribs having photosensitivity is formed on a substrate, the material layer is patterned by exposure and development, and then firing is performed. The firing (partition rib firing step) is performed in air at a firing temperature of 560 ° C.
It is a degree. The firing time is about 2 hours.

Next, three primary color phosphor layer slurries are sequentially printed between the partition ribs 24 formed on the second substrate 21.
Then, the second substrate 21 is baked in a baking furnace to form the phosphor layers 25R, 25G, 25B on the insulating film between the partition ribs 24 and on the side wall surfaces of the partition ribs 24. The firing temperature at that time (fluorescent substance firing step) is 510 °.
It is about C. The firing time is about 10 minutes.

Next, the plasma display device is assembled. That is, first, for example, by screen printing, the second
A sealing layer is formed on the peripheral portion of the panel 20. Then the first
The panel 10 and the second panel 20 are bonded together and fired to cure the seal layer. After that, the first panel 10 and the second
After the space formed between the panel 20 and the panel 20 is exhausted, a discharge gas is filled in and the space is sealed to complete the plasma display device 2.

Action of Plasma Display Device An example of the AC glow discharge operation of the plasma display device having such a configuration will be described. First, for example, a panel voltage higher than the discharge start voltage Vbd is applied to each of the pair of discharge sustaining electrodes 12 for a short time. This causes glow discharge, wall charges are accumulated on the surface of the dielectric layer 14 in the vicinity of both the discharge sustaining electrodes 12, and the apparent discharge starting voltage is lowered. Thereafter, while applying a voltage to the address electrode 22, by applying a voltage to one of the sustain electrodes 12 of the pair of sustain electrodes included in the discharge cells that are not to be displayed, the address electrode 22 and one of the discharge sustain electrodes are discharged. Glow discharge is generated between the storage electrode 12 and the sustain electrode 12 to erase the accumulated wall charges. This erase discharge is sequentially executed at each address electrode 22. On the other hand, no voltage is applied to one of the sustain electrodes included in the discharge cell for displaying. This maintains the accumulation of wall charges. After that, by applying a predetermined pulse voltage between all the pair of discharge sustaining electrodes 12, glow discharge is started between the pair of discharge sustaining electrodes 12 in the cell in which the wall charges are accumulated, and in the discharge cells. The phosphor layer excited by the irradiation of vacuum ultraviolet rays generated based on glow discharge in the discharge gas in the discharge space exhibits a unique emission color according to the type of the phosphor layer material. Note that the phases of the discharge sustaining voltages applied to one of the pair of discharge sustaining electrodes and the other of the pair of discharge sustaining electrodes are shifted by a half cycle, and the polarities of the electrodes are inverted according to the AC frequency.

In the plasma display device 2 of the present embodiment, as described above, since the step shape of the covering portion of the bus electrode 13 is flattened on the surface of the dielectric layer 14, abnormal discharge due to the step shape is generated. It can be suppressed, and the reliability of the plasma display device 2 is improved.

Further, since the high withstand voltage dielectric film 14b such as a silicon oxide film is used as a part of the dielectric layer 14, the total thickness T0 of the dielectric layer 14 can be reduced and the total thickness T0 can be reduced. The dielectric constant of can also be reduced. As a result, the electrostatic capacity between the discharge sustaining electrodes 12 becomes small, the current for charging / discharging can be suppressed, and the load on the drive circuit is reduced. That is, the plasma display device 2
The manufacturing cost can be reduced, and the cost can be reduced.

Further, since the electrostatic capacitance between the discharge sustaining electrodes 12 becomes small, the collapse of the applied voltage waveform at the ends of the discharge sustaining electrodes 12 is suppressed to a small extent, and the image non-uniformity at both ends of the display screen is suppressed. It is possible to suppress the sex. That is,
It is possible to increase the area of the display screen and obtain a uniform image.

Further, since the total capacitance of the dielectric layer 14 is small, the efficiency of light emission is improved as compared with the plasma display device in which the dielectric layer is formed only by the paste dielectric film having the same thickness. Furthermore, since the total thickness of the dielectric layer 14 can be reduced, the electrode gap W1 can be reduced, and as a result, the pixel pitch can be reduced and a high-definition display device can be realized. You can

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention.

For example, the plan view shape of the discharge sustaining electrode is not limited to that shown in FIG. 3 and can be variously modified.
For example, in the embodiment shown in FIG. 4, the discharge sustaining electrode 12a
Are formed in a strip shape along the longitudinal direction of the bus electrode 13, and each pixel has a rectangular transparent electrode. Other configurations are the same as those in the above embodiment. In the present embodiment, the transparent discharge sustaining electrodes 12a are formed in a strip shape, so that the electrode area can be reduced, and as a result, the electrostatic capacitance between the discharge sustaining electrodes 12a can be further reduced, and the display screen is accordingly reduced. It is possible to reduce the non-uniformity of the image quality at both ends of the. In addition, the load on the drive circuit can be reduced, and a display device having such a large area can be realized.

Further, in the embodiment shown in FIG. 5, the shape of the strip-shaped transparent electrode in the discharge sustaining electrode 12b is substantially T-shaped for each pixel. Other configurations are the same as those of the embodiment shown in FIG. 4, and have the same operational effect. Further, in the present invention, the specific structure of the plasma display device is not limited to the embodiment shown in FIG. 1, and other structures may be used.

[0066]

As described above, according to the present invention, since the step shape of the covering portion of the bus electrode is flattened on the surface of the dielectric layer, abnormal discharge caused by the step shape is suppressed. Therefore, the reliability of the plasma display device is improved.

Further, since a high withstand voltage dielectric film such as a silicon oxide film is used as part of the dielectric layer, the total thickness of the dielectric layer can be reduced and the total dielectric constant can be reduced. It can be reduced. As a result, the electrostatic capacitance between the discharge sustaining electrodes is reduced, the current for charging / discharging can be suppressed, and the load on the drive circuit is reduced. That is, the manufacturing cost of the plasma display device can be reduced, and the cost reduction can be realized.

Furthermore, since the electrostatic capacity between the discharge sustaining electrodes becomes small, the collapse of the applied voltage waveform at the ends of the discharge sustaining electrodes is suppressed to a small extent, and the non-uniformity of the image at both ends of the display screen is suppressed. Can be suppressed. That is, it is possible to increase the area of the display screen and obtain a uniform image.

Further, since the total capacitance of the dielectric layer is small, the efficiency of light emission is improved as compared with the plasma display device in which the dielectric layer is formed only by the paste dielectric film having the same thickness. Further, since the total thickness of the dielectric layer can be reduced, the electrode gap can be reduced, and as a result, the pixel pitch can be reduced and a high-definition display device can be realized. .

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a main part of a plasma display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts taken along the line II-II shown in FIG.

FIG. 3 is a schematic plan view of a main part showing the relationship between the discharge sustaining electrodes and the barrier ribs shown in FIG.

FIG. 4 is a schematic plan view of a main part showing a relationship between a discharge sustaining electrode and a barrier rib according to another embodiment of the present invention.

FIG. 5 is a schematic plan view of a main part showing a relationship between a discharge sustaining electrode and a barrier rib according to another embodiment of the present invention.

[Explanation of symbols]

2 ... Plasma display device 4 ... Discharge space 10 ... First panel 11 ... First substrate 12 ... Discharge sustaining electrode 13 ... Bus electrode 14 ... Dielectric layer 14a ... Flattened dielectric film 14b ... High withstand voltage dielectric film 15 ... Protective layer 20 ... Second panel 21 ... Second substrate 22 ... Address electrode 24 ... Partition wall 25R, 25G, 25B ... Phosphor layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shuichi Saito             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F-term (reference) 5C027 AA06 AA07                 5C040 FA01 FA04 GB03 GB14 GC02                       GD02 GD09 MA12 MA23

Claims (11)

[Claims] 1. A first panel in which a plurality of pairs of discharge sustaining electrodes and a dielectric layer covering the discharge sustaining electrodes are formed inside, and the first panel and the first panel are bonded together so that a discharge space is formed inside the first panel. And a second panel, in which the dielectric layer covers the discharge sustaining electrode, and has a withstand voltage characteristic superior to that of the flattened dielectric film covering the flattened dielectric film. And a high withstand voltage dielectric film. 2. The plasma display device according to claim 1, wherein the dielectric constant of the high withstand voltage dielectric film is smaller than 5. 3. The plasma display device according to claim 2, wherein the high withstand voltage dielectric film is a silicon oxide film. 4. The plasma display device according to claim 1, wherein the high withstand voltage dielectric film is formed by a sputtering method, a vapor deposition method, or a chemical vapor deposition method. 5. The plasma display device according to claim 1, wherein the flattening dielectric film is a low melting point glass film. 6. The film thickness of the flattening dielectric film is 3 to 10 μm.
m, and the film thickness of the high withstand voltage dielectric film is 3 to 10 μm.
The plasma display device according to claim 1, wherein 7. The discharge sustaining electrode is a transparent electrode, and a bus electrode having a resistance lower than that of the discharge sustaining electrode is formed on each discharge sustaining electrode. The plasma display device according to 1. 8. The discharge sustaining electrode is formed in a strip shape along the longitudinal direction of the bus electrode, and has an island-shaped transparent electrode for each pixel. Plasma display device. 9. Inside the second panel, there are formed address electrodes that intersect with the longitudinal direction of the bus electrodes, partition walls that partition the discharge space, and phosphor layers disposed between the partition walls. 9. The AC drive type plasma display device according to claim 1. 10. A step of forming a plurality of pairs of discharge sustain electrodes inside the first panel, and a step of forming a planarizing dielectric film inside the first panel so as to cover the discharge sustain electrodes. The first high-voltage dielectric film having a higher withstand voltage characteristic than the flattening dielectric film is formed so as to cover the flattening dielectric film.
A method of manufacturing a plasma display device, comprising: a step of forming inside a panel; and a step of attaching a second panel so that a discharge space is formed inside the first panel. 11. The flattened dielectric film is formed by a paste coating method, and the high withstand voltage dielectric film is formed by a sputtering method, a vapor deposition method, or a chemical vapor deposition method. Item 11. A method for manufacturing a plasma display device according to item 10.