JP4237469B2 - Display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a display device using electron emission into a vacuum formed between a front substrate and a back substrate, and in particular, a cathode wiring having an electron source and an electron extraction amount (emission amount) from the electron source. In addition, the present invention relates to a display device having a stable display characteristic in which a control electrode for controlling the display is installed and a vacuum is maintained between a front substrate and a rear substrate.
[0002]
[Prior art]
Conventionally, a color cathode ray tube has been widely used as a display device excellent in high luminance and high definition. However, with the recent increase in image quality of information processing apparatuses and television broadcasting, there is an increasing demand for a flat display (panel display) that has high luminance and high definition characteristics and is lightweight and space-saving.
[0003]
As typical examples, liquid crystal display devices, plasma display devices and the like have been put into practical use. In particular, a display device utilizing electron emission from an electron source to a vacuum as a display device capable of increasing brightness, a so-called electron emission display device or a field emission display device, and low power consumption Various types of panel type display devices such as an organic EL display have been put into practical use.
[0004]
Among such panel type display devices, the field emission display device includes C.I. A. One having an electron emission structure invented by Spindt et al., One having a metal-insulator-metal (MIM) type electron emission structure, and an electron emission structure utilizing an electron emission phenomenon by a quantum tunnel effect (surface conduction electron) (Also referred to as a source), and those utilizing an electron emission phenomenon such as a diamond film, a graphite film, and a carbon nanotube are known.
[0005]
Among such panel type display devices, the field emission display includes a front panel having an anode electrode and a phosphor layer on the inner surface, and a rear panel having a field emission cathode and a grid electrode as a control electrode. For example, they are bonded and sealed at intervals of 0.5 mm or more, and the sealed space between the two panels is set to a pressure lower than the atmospheric pressure or a vacuum.
[0006]
In recent years, the use of carbon nanotubes (CNT) as a field emission electron source constituting the cathode of this type of flat display has been studied. A carbon nanotube is an aggregate of carbon nanotubes in which a large number of extremely thin needle-like carbon compounds (strictly speaking, a so-called graphene sheet in which carbon atoms are bonded in a hexagonal shape are formed in a cylindrical shape) is used as a cathode electrode. It is fixed. By applying an electric field to the cathode electrode having the carbon nanotubes, high-efficiency and high-density electrons can be emitted from the carbon nanotubes. By exciting the phosphor with these electrons, various displays with high luminance can be obtained. A flat panel display capable of displaying devices and images can be configured.
[0007]
FIG. 13 is a schematic diagram illustrating the basic configuration of a field emission display. CNT is a carbon nanotube provided on a cathode (cathode electrode) K, A is an anode (anode electrode), and a phosphor PH is formed on the inner surface of the anode A. A lattice electrode G for controlling the emission of electrons is provided in the vicinity of the cathode K. When a voltage Vs is applied between the cathode K and the lattice electrode G, electrons are emitted from the carbon nanotube CNT. By applying a high voltage Eb between the cathode K and the anode A, the electrons e emitted from the carbon nanotubes CNT are accelerated to excite the phosphor PH, and the colored light L depending on the composition of the phosphor PH is emitted. .
[0008]
For example, the luminance of the color light L can be controlled by controlling the amount of electrons emitted by the modulation voltage Vs applied to the grid electrode G provided in the vicinity of the cathode K.
[0009]
FIG. 14 is a schematic cross-sectional view illustrating a configuration example of a field emission display. This field emission display (FED) includes a front substrate 2 made of a glass plate as well as a rear substrate 1 made of a glass plate, and has a height of, for example, about 1 mm and is inserted around the display area. The gaps are bonded together via a frame-like support 3 that holds a predetermined interval, and the internal sealed space is vacuum-sealed. A cathode wiring 13, an insulating layer 14, and a grid electrode 15 are provided on the inner surface of the rear substrate 1, and an anode electrode 11 and a phosphor 12 are formed on the inner surface of the front substrate 2. The cathode wiring 13 is provided with carbon nanotubes of an electron source (not shown).
[0010]
FIG. 15 is a schematic plan view of the field emission display shown in FIG. 14 as viewed from the rear substrate 1 side. In the effective display area AR on the inner surface of the front substrate 2, phosphors R, G, and B of three colors are provided. Each pixel is partitioned by a partition wall 16 in this example. In the case of monochrome display, all phosphors are configured in the same color.
[0011]
Such a panel display composed of two panels has the same structure in a plasma display (PDP) and a panel display (MIM-FED) having a metal-insulator-metal type field emission source. In the following, the description of the present invention will be described using the FED as an example, but the present invention can be similarly applied to a PDP or a MIM-FED. The same applies to a display using a surface conductive element.
[0012]
As a disclosure of the prior art of this type of panel display, Patent Document 1 discloses a configuration in which a getter storage chamber is separately provided in order to cover that the exhaust conductance is small. Further, Patent Document 2 discloses a configuration in which an inert gas is introduced into high-temperature exhaust gas to prevent gas adsorption to the getter. Furthermore, Patent Document 3 discloses a configuration in which sealing and exhausting are performed in a vacuum chamber.
[0013]
[Patent Document 1]
JP 2000-149788
[0014]
[Patent Document 2]
JP 2002-75202 A
[0015]
[Patent Document 3]
JP 2002-56777 A
[0016]
[Problems to be solved by the invention]
In the field emission type display device described above, electrons from the electron source pass through the aperture of the control electrode and strike the phosphor of the anode, which is excited and emitted to display, with high brightness, It has an excellent configuration that enables high-definition characteristics and a lightweight, space-saving flat panel display. However, there is a problem to be solved regardless of such an excellent configuration. That is, in a flat panel display in which the distance between the front substrate and the rear substrate, such as the FED described above, is relatively large, it is important to perform the fusion process of the seal mechanism for maintaining the bonding interval between the two substrates at a predetermined value.
[0017]
Further, in a flat panel display having a wide display area, an exhaust process in which a sealed space formed by the front substrate, the rear substrate, and the support is set to a low pressure or a vacuum is important. In other words, in a flat panel display having a wide display area, the sealed space formed by the front substrate, the back substrate, and the support body is evacuated to a low pressure or vacuum, and the sealed space is interposed between both substrates and a support body interposed therebetween. In the above-mentioned patent document 3, a manufacturing method is proposed in which when the sealing member is formed by melting the sealing member, the whole is heat-treated in a baking furnace. However, when the gap between the front substrate and the rear substrate is melted to a predetermined value from the beginning and fused and exhausted, the conductance of the sealed space is small, so that it becomes difficult to exhaust and a desired degree of vacuum is obtained. There is a problem that it is difficult to be done.
[0018]
This problem, for example, in an FED or plasma display using carbon nanotubes as an electron emission source, leads to shortened life characteristics and reduced product reliability unless the degree of vacuum is sufficient.
[0019]
Further, in the MIM-FED, when the inner surface of the panel is processed at a high temperature, so-called hillocks are easily generated, and the defect rate is increased. Further, even when carbon nanotubes are used as an electron emission source, there is a problem that a part or all of them disappear when the processing temperature is high. In addition, this method has a problem that a huge exhaust device is required.
[0020]
In the manufacturing method of the structure which separately provides the getter storage chamber disclosed in Patent Document 1, there is a difficulty in applying to a large size because the exhaust chamber uses a vacuum chamber. And in the manufacturing method which introduce | transduces an inert gas at the sealing process disclosed by patent document 2, there exists a possibility that the said structural member may reabsorb a residual gas conversely by the gas absorption and discharge | emission characteristic which a structural member has. In addition, there are problems such as difficulty in ensuring the reliability of air-sealing due to the remaining fine holes in the melted sealing member, and it has been a problem to solve these problems together with the various problems described above. .
[0021]
One object of the present invention is to provide a long-life display device capable of solving the above-described problems and ensuring the reliability of hermetic sealing. Another object of the present invention is to provide a method of manufacturing a display device that solves the various problems described above and can easily secure a desired degree of vacuum.
[0022]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has a configuration in which the protruding shape of the sealing member of the sealing portion between both substrates and the support is different between the inner side which is the display region side and the outer side which is the air side on the opposite side. It is characterized by that. Further, the present invention provides the sealing member in the step of hermetically sealing the end face of the support and the two substrates through the sealing member, and the step of exhausting the space surrounded by the support and the two substrates. It is characterized by processing along the properties of Hereinafter, representative configurations of the display device and the manufacturing method thereof according to the present invention will be described.
[0023]
A display device according to the present invention includes a front substrate having an anode and a phosphor on its inner surface, a plurality of cathode wirings extending in one direction and arranged in parallel in the other direction intersecting the one direction and having an electron source, A control electrode facing the cathode wiring in a display area in a non-contact manner and having an electron passage hole through which electrons from an electron source pass to the front substrate side, and the control substrate and the cathode wiring on the inner surface. And a rear substrate opposed to each other at a predetermined interval, a support member that is inserted around the display area between the front substrate and the rear substrate, and maintains a predetermined interval, an end surface of the support member, the front substrate, It has a sealing member that hermetically seals the back substrate, and the protruding shape from the support of the sealing member to the display region side is different from the protruding shape to the opposite side.
[0024]
Also, the protruding dimension from the support of the sealing member to the display area is different from the protruding dimension to the opposite side, and the protruding dimension from the support of the sealing member to the display area is larger than the protruding dimension to the opposite side. And The sealing member can be made of a glass material including amorphous frit glass. Then, a dispersion getter is provided close to the display region side of the support, and the control electrode can be constituted by arranging a plurality of strip electrode elements in parallel.
[0025]
The display device according to the present invention is sealed in a step of hermetically sealing the end face of the support and both substrates via a sealing member, and a step of exhausting a space surrounded by the support and both substrates. The process of exhausting the space once in synchronization with the start of softening of the member, the process of raising the temperature to a temperature at which the sealing member exhibits fluidity, and the temperature lowering to a temperature that is higher than the softening start temperature and does not exhibit fluidity. And further exhausting the main exhaust.
[0026]
Further, the display device according to the present invention includes a step of hermetically sealing the end face of the support and both substrates through a sealing member, and a step of exhausting a space surrounded by the support and both substrates, The process of exhausting the space once almost in synchronization with the start of softening of the sealing member, the process of raising the temperature to a temperature at which the sealing member exhibits fluidity, and the temperature above the softening start temperature and not exhibiting fluidity A step of exhausting the exhaust gas after the temperature has decreased and a flushing step with an inert gas that is performed at a temperature equal to or lower than the softening start temperature and that is performed in the exhaust gas can be provided.
[0027]
In each of the above manufacturing methods, an aging process can be performed immediately before the flushing process, and by these manufacturing methods, a long-life display device with a desired degree of vacuum and a highly reliable hermetic seal can be obtained. Can do.
[0028]
It should be noted that the present invention is not limited to the above-described configuration and the configuration of the embodiments described later, and it goes without saying that various modifications can be made without departing from the technical idea of the present invention.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings of the embodiments. 1 to 4 are explanatory views of an embodiment of a display device according to the present invention, FIG. 1 is an explanatory view of a schematic configuration of a field emission type display device, and FIG. 1 (a) is viewed from the front substrate side. The schematic plan view, (b) is a schematic side view of (a) seen from the direction of arrow A. 2 is an explanatory diagram of a configuration example of the back plate constituting the display device shown in FIG. 1, FIG. 2 (a) is a schematic plan view seen from the upper side in the z direction, and FIG. 2 (b) is an arrow with the same (a). The schematic side view seen from the B direction is shown. 3 is a schematic cross-sectional view taken along the line CC of FIG. 2, and FIG. 4 is a schematic enlarged view of a portion D of FIG.
[0030]
1 to 4, reference numeral 1 is a back substrate, 2 is a front substrate, 3 is a support member also serving as an outer frame, and 4 is an exhaust pipe. The back substrate 1 has a plurality of cathode wirings 5 having an electron source on the surface of an insulating substrate preferably made of glass such as glass having a thickness of several mm, for example, 3 mm, or alumina, and extending in one direction (x direction). They are arranged in parallel in the other direction (y direction) intersecting with one direction. The cathode wiring 5 is formed by patterning a conductive paste containing silver or the like by printing or the like. An end portion of the cathode wiring 5 is led out to the outside of the support 3 which also serves as an outer frame as a cathode wiring lead-out line 5a. On the cathode wiring 5, a metal-insulator-metal (MIM) type electron-emitting device, an electron-emitting structure (also referred to as a surface conduction electron source) device utilizing an electron emission phenomenon due to a quantum tunnel effect, a diamond film, An electron source 51 made of either a graphite film or a carbon nanotube is provided.
[0031]
Further, it is close to the upper side of the cathode wiring 5 (front substrate 2 side), that is, close to about 0.1 mm or less, and is disposed to face the cathode wiring 5 over at least the entire display area AR. And a plurality of plate-like control electrodes 6 extending in the y direction and arranged in parallel in the x direction. Reference numeral 7 denotes an electrode pressing member. The member 7 fixes and holds the control electrode 6 outside the effective display area AR and inside the support 3 that also serves as an outer frame on the rear substrate. Each control electrode 6 is configured to be connected to an external circuit via a control electrode lead line 40 (only one is shown in FIG. 2A). An exhaust hole 8 is formed in the back substrate 1 and communicates with the exhaust pipe 4.
[0032]
Then, a support 3 that also circulates around the display area AR and also serves as an outer frame is inserted in a gap between the rear substrate 1 and the front substrate 2, and the support 3 that also serves as the outer frame and both the substrates 2 and 3. The enclosed internal space 9 is hermetically sealed with a sealing member 10 and evacuated to a predetermined degree of vacuum. The height of the support 3 is set to about 0.5 to 3 mm, for example. The front substrate 2 has substantially the same thickness as the back substrate 1 and is stacked with respect to the back substrate 1 in the z direction. z indicates a direction orthogonal to the substrate surfaces of the back substrate 1 and the front substrate 2. In FIG. 2, the exhaust pipe is shown in a state before sealing.
[0033]
The plate-like control electrode 6 is constituted by arranging a number of strip-like electrode elements (metal ribbons) 61 having a plurality of electron passage holes 6a in parallel, and in the development process leading to the present invention. This has been proposed by the present inventors and is not a publicly known one. These strip-shaped electrode elements 61 are made of iron-based stainless steel or iron material, and have a thickness of, for example, about 0.025 mm to 0.150 mm. The strip electrode element 61 extends in the y direction and is juxtaposed in the x direction to constitute the control electrode 6.
[0034]
The plate-like control electrode 6 has a uniform gap with the cathode wiring 5 as compared with the control electrode formed by depositing a metal thin film on the insulating layer as shown in FIG. 13 by vapor deposition or the like. It is easy to achieve, and it is possible to obtain a high-quality video display by making the control characteristics of individual pixels uniform over the entire display area.
[0035]
Further, the plate-like control electrode 6 is manufactured as a separate part in a separate process, and is installed close to the upper side (front substrate side) of the cathode wiring 5 having the electron source, outside the effective display area AR, and The vicinity of both ends is fixed to the back substrate 1 with an electrode pressing member 7 made of an insulator such as a glass material provided inside the support 3 that also serves as an outer frame. A lead wire 40 is connected to the control electrode 6 in the vicinity of the electrode pressing member 7 or in the vicinity of the support 3 that also serves as an outer frame, and is drawn out to the outer edge of the display device. The electron source 51 and the electron passage hole 6a are arranged to face each other at the intersection between the cathode wiring 5 and the plate-like control electrode 6.
[0036]
One or a plurality of the electron passage holes 6 a are arranged at the intersection with the cathode wiring 5 at a position coaxial with the electron source 51, and allow electrons from the electron source 51 to pass to the anode 21 side. The distance between the anode 21 and the control electrode 6 is set to several mm, for example, about 3 mm. In this example, the anode 21 is also used as a metal back film.
[0037]
In such a configuration, electrons emitted from the electron source 51 are controlled by the electron passage hole 6a of the control electrode 6 to which a grit voltage of about 100V is applied and pass therethrough, and an anode voltage of several KV to several tens KV. Is applied to the phosphor 22 covered with the anode 21 of the front substrate 2 to emit light, and a desired display is performed. Reference numeral 23 denotes a black matrix (BM) film. In this embodiment, the phosphor screen composed of the BM film 23, the phosphor 22 and the anode 21 has substantially the same configuration as a conventional color cathode-ray tube phosphor screen.
[0038]
Reference numeral 24 is a getter, 25 is a plate-like spacer, and the getter 24 is a dispersion getter, that is, an evaporation type getter such as a Ba getter. The getter film is disposed in such a direction that most of the getter film is deposited. The number of getters 24 may be determined by the substrate size, the amount of getters, and the like, and it is more effective when used in combination with a non-evaporable getter. The spacers 25 are arranged in parallel with the extending direction (x direction) of the cathode wiring 5 and are inserted between the cathode wirings 5, and their upper and lower end surfaces are in contact with the back substrate 1 and the front substrate 2, respectively. It has become.
[0039]
The arrangement direction, the number and arrangement positions of the spacers 25 may be determined by the substrate dimensions and the like. Further, in this embodiment, for example, if the spacers 25 are arranged outside the outermost cathode wirings in parallel with the cathode wirings, evaporation is performed. The effect of being able to shield the anode and the control electrode from the obtained getter material can also be expected, and it may be determined in consideration of the dimensions and the like. Further, for example, a spacer having the same composition as the sealing member 10 can be used for fixing the spacer 25 to both substrates.
[0040]
The sealing member 10 is made of a glass material containing an amorphous type frit glass, and performs hermetic sealing between the support 3 and the two substrates 1 and 2 as described above. The protruding shapes from the inner side surface 3i and the outer side surface 3o of the support 3 of the subsequent sealing member 10 are different inside and outside. That is, the protruding portion 10i from the inner side surface 3i which is the display area side is formed thicker than the protruding portion 10o from the outer side surface 3o on the opposite side, and extends and protrudes in the direction of the counter substrate. It has a shape to do. Explaining this in detail, the protruding portion 10i from the inner surface 3i on the display region side has a substantially elliptical cross section in the z-axis direction, whereas the protruding portion 10o from the opposite outer surface 3o. The shape is substantially a wedge shape.
[0041]
Further, the protruding dimension Ti of the protruding portion 10i from the inner side surface 3i which is the display area side is in a relationship of Ti> To with respect to the protruding dimension To of the protruding portion 10o from the opposite outer surface 3o. Further, in this embodiment, the protrusion length Li from the end surface of the support 3 to the counter substrate direction of the protruding portion 10i from the inner surface 3i which is the display area side is the counter substrate direction of the protruding portion 10o from the outer surface 3o on the opposite side. With respect to the protrusion length Lo, the relationship is Li> Lo. Incidentally, it is sufficient that the Ti and To have a relationship of Ti> To, but if the difference is 15% or more, the reliability of the degree of vacuum can be ensured. On the other hand, if the difference exceeds 500%, the arrangement relationship with other members may be restricted, which is not practical. Desirably, it is 100% to 400%, and more preferably 200% to 300%.
[0042]
Further, if the cross-sectional shape in the z-axis direction of the protruding portion 10i from the inner side surface 3i that is the display area side is close to a substantially elliptical shape as in the embodiment, the inside of the front substrate 2 from the inner side surface 3i by the getter flash. The getter film deposited over the surface becomes discontinuous at the protruding portion 10i, thereby having an effect of ensuring the withstand voltage between the two substrates. The shape of the protruding portion exhibits various shapes depending on various factors such as the material of the sealing member, the heating temperature at the time of sealing, the pressure applied at the time of sealing, the presence / absence of the getter, the arrangement position, the desired degree of vacuum, Furthermore, an optimum one may be selected based on the substrate, electrode dimensions, and the like. With such a configuration, it is possible to ensure the reliability of hermetic holding of the sealing portion, and a long-life display device is possible.
[0043]
Next, a method for manufacturing the display device of the present invention will be described. 5 and 6 are schematic views of an example of a manufacturing apparatus for explaining a method for manufacturing a display device according to the present invention. FIG. 5 is a partially cutaway front view, and FIG. 6 is a plan view. The same parts are denoted by the same reference numerals. 5 and 6, a panel assembly 28 is placed on a base 26 via a heat-resistant cushion material 27 made of aramid fibers or the like so that the front substrate 2 faces downward and the exhaust pipe 4 faces upward. This panel assembly 28 has the structure shown in the panel assembly 28 in the process diagram for explaining the manufacturing method of the present invention shown in FIG. 7, and includes both the substrates 1 and 2 and the cathode wiring 5 of the panel assembly 28. The structure of each part is shown in FIGS. In this step, the sealing member 10 is still in a non-molten state including a binder and has a configuration before hermetic sealing.
[0044]
On the upper side of the panel assembly 28, that is, on the back substrate 1, an upper plate 29 made of a metal material having heat resistance such as stainless steel is placed via a cushion material 30 made of the same material as the cushion material 27. To do. By interposing the heat resistant cushion material 27 on the outer surface of the front substrate 2, damage to the outer surface of the front substrate 2 can be prevented and at the same time, damage to the outer surface of the rear substrate 1 can be prevented by inserting the cushion material 30. Is possible.
[0045]
The upper plate 29 and the cushion material 30 have dimensions that cover substantially the entire surface excluding the portion where the exhaust pipe 4 of the rear substrate 1 is implanted, and the base 26 and the cushion material 27 are larger than the area of the front substrate 2. It ’s fine. Further, as shown by a thick arrow 31, air pressure is used for pressurization when the substrates 1 and 2 and the support 3 are hermetically sealed by the sealing member 10. By using this air pressure, a substantially uniform applied pressure is applied to the entire surface of the substrate, and the occurrence of a local incomplete seal can be prevented. Next, as shown in FIGS. 5 and 6, the panel assembly 28 incorporated in the manufacturing apparatus is sealed and subjected to exhaust baking. In this embodiment, amorphous frit glass was used as the sealing member 10.
[0046]
FIG. 8 is an explanatory view of the exhaust baking process of the embodiment of the manufacturing method of the display device of the present invention. In FIG. 8, the horizontal axis is time t (h), the left vertical axis is temperature T (° C.), the right vertical axis is vacuum pressure P (Pa), 81 is a baking process temperature line, and 82 is shown. The curve shown shows the vacuum curve. First, the exhaust pipe 4 is connected to an exhaust device (not shown). Next, heating is started according to the schedule indicated by the baking process temperature line 81 in FIG. 8, and pre-stage exhaust is started at a point P11 that reaches about 350 to 370 ° C. just before the sealing member 10 is softened. To do. The pre-exhaust is temporarily stopped after the degree of vacuum at the point P21 indicated by the vacuum degree curve 82 reaches the point P22 at which the degree of vacuum is about 10 (Pa). With this pre-stage exhaust, most of the residual gas desorbed in the internal space 9 up to this point is discharged out of the panel assembly 28.
[0047]
Next, the temperature is raised to a point P12 of about 410 to 440 ° C. at which the sealing member 10 fully develops fluidity. With this temperature rise, fine bubbles and holes remaining in the sealing member 10 itself are closed by the surface tension of the sealing member 10 itself. At this time, since the temperature of the effective region does not become higher than the set baking temperature, the electron emission characteristics of the electron emission source are deteriorated, and the non-uniform spacing due to the distortion of the glass is avoided. After holding the sealing member 10 at a temperature at which the fluidity is fully developed for about 5 to 30 minutes, the temperature is lowered to a point P13 at about 400 ° C. at which the fluidity is not exhibited, and this temperature is maintained for a certain period of time.
[0048]
Next, after about 10 minutes have elapsed from the point P13 where the temperature of about 400 ° C. is maintained, the main exhaust is started, and the main exhaust is continued until the point P14 while the temperature of about 400 ° C. is maintained. The main exhaust time may be determined by the capacity of the internal space 9, the capacity of the exhaust device, and the like. Thereafter, the baking temperature is gradually lowered to room temperature while continuing the main exhaust, the sealing member 10 is cured, and the hermetic sealing between the two substrates and the support and the exhaust baking process are completed. During these steps, the pressure applied to the panel assembly 28 is continued until the processing is completed, and the interval between the substrates is fixed to a predetermined size when the sealing member 10 is cured.
[0049]
Through the above steps, exhaust can be performed with the gap between the front substrate and the back substrate being larger than the interval at the time of completion, so the exhaust conductance is good, sufficient exhaust is possible, and the sealed internal space The degree of vacuum of 9 is improved.
[0050]
After completion of the hermetic sealing and exhaust baking, the exhaust pipe 4 is chipped off, and the getter flash is performed by heating the getter 24 to obtain a high degree of vacuum of about 10E-5 (Pa) or less. Thereafter, aging of the characteristic stabilization process, heat transfer, etc. are performed to complete a desired display device.
[0051]
FIG. 9 is an explanatory view of the exhaust baking process of another embodiment of the display device manufacturing method of the present invention. The process shown in FIG. 9 is a processing method in which the hermetic sealing between the two substrates and the support, which are aligned via the sealing member similar to the above-described embodiment, and the exhaust baking process are integrated. In FIG. 9, the horizontal axis is time t (h), the left vertical axis is the temperature T (° C), the right vertical axis is the vacuum pressure P (Pa), 81 is the baking process temperature line, 82 The curve shown shows the vacuum curve.
[0052]
In this embodiment, the pre-exhaust and the main exhaust are performed in the same process as in the above-described embodiment, and the temperature lowering process of gradually lowering the baking temperature to room temperature from the point P14 where the temperature of about 400 ° C. is maintained during the main exhaust is continued. In the middle of the temperature of about 250 ° C., a flushing process using an inert gas such as a rare gas is inserted. This indicates that glass materials used for substrates and the like constituting the panel assembly 28 generally have a tendency to gradually increase gas adsorption at 220 to 230 ° C. or less due to the temperature characteristics of gas adsorption and gas release of the glass material. For this reason, the gas once released into the internal space 9 at a high baking temperature is not exhausted to the outside with the reduction of the baking temperature, but is adsorbed to the substrate or the like and remains in the apparatus as it is. There is a risk that it will be re-released during operation after completion, adversely affecting emissions, and causing a deterioration in service life.
[0053]
The point P23 of the vacuum curve 82 in FIG. ₂ O, CO, CO ₂ This indicates that the degree of vacuum temporarily decreased due to the re-release of harmful residual gases including gases that are likely to adversely affect emissions such as these. However, since the evacuation is continued during the flushing process, the residual gas is immediately evacuated and the degree of vacuum is improved in a short time.
[0054]
Through the above steps, exhaust can be performed with the gap between the front substrate and the back substrate being larger than the interval at the time of completion, so exhaust conductance is good, sufficient exhaust is possible, and the internal space 9 is vacuumed. The degree is improved. Further, even when carbon nanotubes are used as an electron emission source, it is possible to suppress the problem that part or all of them disappear due to high temperature treatment. Even when other electron sources are used, problems caused by high-temperature treatment can be suppressed by applying the present invention.
[0055]
Furthermore, by adding a flushing process, the gas re-adsorbed on the substrate and the like can be eliminated during the manufacturing process, so that not only the vacuum of the sealed internal space 9 is improved, but also harmful gas release during operation after completion is suppressed. It is possible to extend the service life. By passing through the above process, the degree of vacuum of the sealed internal space surrounded by both the substrates, the support and the sealing member is improved, and a display device in which the distance between both the substrates is a predetermined value is obtained.
[0056]
FIG. 10 is an explanatory view of the exhaust baking process of still another embodiment of the display device manufacturing method of the present invention. This embodiment is also a processing method in which the hermetic sealing and the exhaust baking process between the two substrates and the support, which are aligned via the sealing member similar to the above-described embodiment, are integrated. In FIG. 10, the horizontal axis is time t (h), the left vertical axis is the temperature T (° C.), the right vertical axis is the vacuum pressure P (Pa), 81 is the baking process temperature line, and 82. The curve shown shows the vacuum curve.
[0057]
In this embodiment, an aging process is further inserted before the flushing process of the process shown in FIG. This aging process is performed by taking out the emission from the electron source.
[0058]
In the present invention, various devices including carbon nanotubes (CNT) can be used as the electron source, and the phosphor screen and the structure having the BM film are also as described above. The CNT and BM films of this electron source are made of a carbon-based material, and many of these carbon-based materials have a gas release peak near 300 ° C. Utilizing this characteristic of having a gas discharge peak near 300 ° C., the gas adsorbed on the CNTs during the manufacturing process is re-released in this aging process. Since the re-released gas continues to be exhausted during this aging process, the re-released gas is immediately exhausted.
[0059]
In addition, by performing the flushing process subsequent to the aging process, the re-released gas is also eliminated without being re-adsorbed to another substrate, for example. Through these steps, it is possible to release the components and prevent re-adsorption, and the effect of both steps can be combined to further improve the degree of vacuum in the internal space. A device is obtained.
[0060]
FIG. 11 is a partially cutaway front view schematically showing another example of the manufacturing apparatus for explaining the manufacturing method of the display device of the present invention, corresponding to FIG. 5 described above, and the same parts as those shown in FIG. The code | symbol is attached | subjected. In FIG. 11, as in FIG. 5, the panel assembly 28 is placed on the base 26 via a heat-resistant cushioning material 27 made of aramid fibers or the like so that the front substrate 2 faces downward and the exhaust pipe 4 faces upward. To do. A cushion material 30 made of the same material as the cushion material 27 is placed on the upper side of the panel assembly 28, that is, on the rear substrate 1. A pressure member 32 is interposed between the cushion material 30 and an upper plate 29 made of a metal material having heat resistance such as stainless steel. Reference numeral 33 denotes a spring that presses the upper plate 29 toward the base 26.
[0061]
The pressurizing body 32 is formed in a bellows shape from a heat-resistant metal material such as stainless steel, and a gas, for example, air is filled into the inside through a tube 34 provided in the pressurizing body 32. It can be extended with The pressurizing body 32 is filled with gas through a pipe 34 to pressurize the panel assembly 28.
With such an apparatus member arrangement, the outer surface of the front substrate 2 is interposed on the outer surface of the front substrate 2 to prevent the outer surface of the front substrate 2 from being damaged, and the outer surface of the rear substrate 1 is also damaged. It is possible to prevent it simultaneously by insertion. The upper plate 29, the pressure member 32, and the cushion material 30 have dimensions that cover substantially the entire surface of the rear substrate 1 except for the portion where the exhaust pipe 4 is implanted, and the base 26 and the cushion material 27 are the front substrate 2. It is sufficient if it is larger than the area.
[0062]
Further, the pressurization when the substrates 1 and 2 and the support 3 are hermetically sealed by the sealing member 10 is achieved by filling the pressurization body 32 with a gas and applying a substantially uniform pressure to the entire surface of the substrate. Pressure can be applied to prevent the occurrence of local incomplete seals. As shown in FIG. 11, a display device can be obtained by sealing and exhaust baking the panel assembly 28 incorporated in the manufacturing apparatus in accordance with, for example, the programs shown in FIGS.
[0063]
Here, examples of the sealing member used in the display device of the present invention include the following composition examples.
(1) Frit glass composition
Pbo (main component) 75-80wt%
B ₂ O _Three About 10wt%
Others 10-15wt%
(2) Frit glass paste composition
The frit glass (1) is about 90 wt% and the vehicle having the composition 3 is about 10 wt%. Both of these are made into a slurry and applied by dispenser or printing.
(3) Vehicle composition
Resin binder Several wt%
Solvent 95wt% or more
Examples of the resin binder include polyisobutyl methacrylate and nitrocellulose, and examples of the solvent include α-terpineol and isoamyl acetate.
[0064]
Moreover, as a heating method at the time of baking, IR (infrared) direct heating, a hot air circulation method, etc. are generally used. Further, a method of raising and lowering the temperature by heating a metal plate such as the base 26 and the upper plate 29 in FIGS. 5 and 6 is also suitable in the present invention.
[0065]
FIG. 12 is an explanatory diagram of an equivalent circuit example of the display device of the present invention. A region indicated by a broken line in the figure is a display region AR, and the cathode wiring 5 and the control electrode 6 (band electrode element 61) are arranged so as to cross each other in this display region AR to form an n × m matrix. Yes. Each intersection of the matrix constitutes a unit pixel, and one group of “R”, “G”, and “B” in the figure constitutes one color pixel. The cathode wiring 5 is connected to the video drive circuit 200 by cathode wiring lead lines 5a (X1, X2,... Xn), and the control electrode 6 is scan-driven by control electrode lead lines 40 (Y1, Y2,... Ym). The circuit 400 is connected.
[0066]
A video signal 201 is input to the video drive circuit 200 from an external signal source, and a scan signal (synchronization signal) 401 is similarly input to the scan drive circuit 400. As a result, predetermined pixels sequentially selected by the strip electrode element 61 and the cathode wiring 5 emit light with the predetermined color light to display a two-dimensional image. With the display device of this configuration example, a flat panel display device with a relatively low voltage and high efficiency is realized.
[0067]
【The invention's effect】
As described above, according to the present invention, the protruding shape of the sealing member in the air-sealing portion between the front substrate and the rear substrate and the support is different between the display region side and the opposite side. It is possible to provide a highly reliable display device that can ensure the reliability of sealing and has a long lifetime.
[0068]
Furthermore, by processing along the properties of the sealing member in the exhaust and baking process, the electron source can be stabilized without exposing the member to high temperatures, and deformation and damage of the substrate can be prevented. Thus, it is possible to provide a display device with long life and high reliability that can avoid display instability and display deterioration.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a schematic configuration of an embodiment of a display device according to the present invention, in which FIG. 1 (a) is a schematic plan view, and FIG. 1 (b) is a schematic side view of FIG. It is.
2 is an explanatory diagram of a configuration example of a back plate constituting the display device of the present invention shown in FIG. 1. FIG. 2 (a) is a schematic plan view, and FIG. 2 (b) is the same (a) in the direction of arrow B. It is the model side view seen from.
FIG. 3 is a schematic cross-sectional view taken along the line CC of FIG.
4 is a schematic enlarged view of a portion D in FIG. 3;
FIG. 5 is a schematic front view of an example of a manufacturing apparatus for explaining a method for manufacturing a display device of the present invention.
6 is a schematic plan view of an example of a manufacturing apparatus for explaining a method of manufacturing the display device of the present invention shown in FIG.
FIG. 7 is a process diagram illustrating a method for manufacturing a display device of the present invention.
FIG. 8 is an explanatory diagram of an exhaust baking process of an embodiment of the display device manufacturing method according to the present invention.
FIG. 9 is an explanatory diagram of an exhaust baking process of another embodiment of the display device manufacturing method of the present invention.
FIG. 10 is an explanatory diagram of an exhaust baking process according to still another embodiment of the display device manufacturing method of the present invention.
FIG. 11 is a schematic plan view of another example of a manufacturing apparatus for explaining a method for manufacturing a display device of the present invention.
FIG. 12 is an explanatory diagram of an equivalent circuit example of a display device of the present invention.
FIG. 13 is a schematic diagram illustrating a basic configuration of a field emission display.
FIG. 14 is a schematic cross-sectional view illustrating a configuration example of a field emission display.
15 is a schematic plan view of the field emission display shown in FIG.
[Explanation of symbols]
1 Back substrate
2 Front substrate
3 Support
3i Inside surface of support
3o Outer surface of support
4 Exhaust pipe
5 Cathode wiring
5a Cathode wiring lead wire
6 Control electrode
6a Electron passage hole
9 Internal space
10 Sealing material
10i Inside protrusion
10o Outward protruding part
21 Metal back (anode)
23 phosphor
28 Panel assembly
40 Control electrode lead wire
51 electron source
61 Strip electrode element
AR display area.

Claims (2)

A front substrate having an anode and a phosphor on its inner surface, a rear substrate having an electron source,
Wherein between the front substrate and the rear substrate interposed orbiting the table display region, a support for holding a predetermined distance,
A display device having an end face of the support and a sealing member that hermetically seals the front substrate and the rear substrate,
A dispersion getter is provided close to the side surface of the support on the display area side,
The sealing member has a protruding shape from the support that is different between an inner side that is the display region side and an outer side that is the atmosphere side, and the shape of the protruding portion to the inner side is substantially elliptical in cross section. The protruding portion has a substantially wedge-shaped cross section,
The sealing member is characterized in that a protruding dimension from the support to the inside is larger than a protruding dimension to the outside, and a getter film by the dispersion getter is discontinuous at the protruding part to the inside. Display device.   The display device according to claim 1, wherein the sealing member includes amorphous frit glass.

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