JP2006120422A - Display and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display stabilizing the resistance value between the divided regions of a low-resistance layer to a desired value, and to provide a method for manufacturing the display. <P>SOLUTION: A plurality of rib layers 21 extended in the X direction and a plurality of irregular layers 22 extended in the Y direction are formed on the inner surface of a front substrate 2, and metal back and getter layers are film-formed via the dividing structures 21, 22, thus stably forming the electrically divided low-resistance layer while being overlapped to regions corresponding to respective phosphor pixels R, G, B. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to, for example, a display device that displays an image by emitting electrons from an electron-emitting device provided on a back substrate and exciting and emitting a phosphor layer provided on the front substrate, and a method for manufacturing the display device.

  In recent years, field emission displays (FEDs), display devices (SEDs) equipped with surface-conduction electron-emitting devices, and the like are known as display devices having a flat envelope having a flat panel structure.

  The FED and SED have a vacuum envelope in which the front and back substrates, which are opposed to each other with a predetermined interval through a spacer, are joined to each other by a rectangular frame-shaped side wall, and the inside is evacuated. ing.

  A phosphor layer of three colors and a metal back covering the phosphor layer are formed on the inner surface of the front substrate, and a large number of phosphor layers corresponding to each pixel of the phosphor layer as an electron emission source for exciting and emitting the phosphor layer on the inner surface of the rear substrate. An electron-emitting device is disposed. Further, in order to maintain a high vacuum inside the vacuum envelope, a getter layer is formed on the inner surface of the front substrate.

  A voltage several kV higher than the electron-emitting device is applied to the phosphor layer, and the electron beam emitted from each electron-emitting device is accelerated by this electric field. Then, the accelerated electron beam is applied to the corresponding phosphor layer, and the phosphor is excited to emit light to display a color image.

  Thus, when a high voltage for accelerating the electron beam is applied between the front substrate and the rear substrate that are close to each other, a discharge problem often occurs. When a discharge occurs, a large amount of current flows through the discharge location, causing damage to the electron-emitting device at that location.

  On the other hand, the metal back covering the phosphor layer of the front substrate is electrically divided into small regions, and the current flowing when the discharge occurs is limited by reducing the resistance between the divided regions by reducing the discharge damage. Techniques are known (see, for example, Patent Document 1 and Patent Document 2). As a method of dividing the metal back, a method of chemically modifying the metal back or a method of partially evaporating the metal back with a laser can be considered.

However, when the metal back is divided into a plurality of small regions by such a conventional method, the resistance value between adjacent regions becomes unstable, causing uneven brightness or inducing discharge between regions. There was a problem. Further, in the above dividing method, it is extremely difficult to control the resistance value between regions to a desired value, and the electrical characteristics of the metal back are unstable.
Japanese Patent Laid-Open No. 10-326583 JP 2000-31642 A

  An object of the present invention is to provide a display device capable of stabilizing a resistance value between divided regions of a low resistance layer to a desired value, and a method for manufacturing the display device.

  In order to achieve the above object, a display device according to the present invention includes a front substrate having a large number of phosphor layers and a low resistance layer on the inside and a back substrate having a large number of electron-emitting devices on the inside facing each other at a predetermined interval. In a display device in which the phosphor layer and the low resistance layer are set to a higher potential than the electron-emitting device, the low resistance layer includes an elongated rib layer protruding in the thickness direction of the front substrate and an uneven surface. It is characterized by being electrically divided into a plurality of island-shaped regions by the elongated uneven layers.

  In addition, according to the method of manufacturing a display device of the present invention, a front substrate having a large number of phosphor layers and low resistance layers on the inside and a back substrate having a large number of electron-emitting devices on the inside face each other at a predetermined interval, and the inside is vacuumed. In a manufacturing method of a display device in which the phosphor layer and the low resistance layer are set to a higher potential than the electron-emitting device in an atmosphere, an elongated rib layer projecting in the thickness direction inside the front substrate and the rib layer intersect A dividing layer forming step of forming a long and narrow uneven layer extending in a direction to be formed, and forming the low resistance layer on the inside of the front substrate through the rib layer and the uneven layer, and forming the low resistance layer into the rib layer and And a film forming step of electrically dividing the plurality of island-shaped regions by the uneven layer.

  According to the above invention, the rib layer and the uneven layer for electrically dividing the low resistance layer into a plurality of island-shaped regions are provided inside the front substrate, and the low resistance layer is formed through the rib layer and the uneven layer. The low resistance layer was divided into a plurality of island regions.

  Since the display device of the present invention has the above-described configuration and operation, the resistance value between the divided regions of the low resistance layer can be stabilized to a desired value.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an SED will be described as an example of a display device according to an embodiment of the present invention.

  As shown in FIGS. 1 to 3, the SED 1 includes a front substrate 2 and a rear substrate 4 each made of a glass plate having a rectangular shape of 1 to 2 mm, and these substrates are about 1.0 to 2 through spacers 8. They are placed facing each other with a gap of 0 mm. The front substrate 2 and the back substrate 4 are joined together via a rectangular frame-shaped side wall 6 to constitute a vacuum envelope 10 whose inside is a vacuum.

  A phosphor screen 12 for displaying an image is formed on the inner surface of the front substrate 2. The phosphor screen 12 is configured such that red, blue, and green phosphor layers R, G, and B and a light shielding layer 11 are arranged in a matrix and the phosphor layer is covered with a metal back 14 (low resistance layer). Each phosphor layer R, G, B is formed in a substantially rectangular dot shape, and the metal back 14 is formed from a metal thin film such as aluminum.

  On the inner surface of the back substrate 4, a number of surface conduction electron-emitting devices 16 that emit an electron beam for exciting and emitting the phosphor layers R, G, and B are provided. These electron-emitting devices 16 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel, and are configured by an electron-emitting unit (not shown) and a pair of device electrodes for applying a voltage to the electron-emitting unit. Further, on the inner surface of the back substrate 4, a large number of wirings 18 for applying a driving voltage to the respective electron-emitting devices 16 are provided in a matrix shape, and end portions thereof are drawn out of the vacuum envelope 10. Yes.

  The front substrate 2 and the rear substrate 4 are degassed and fired in a vacuum atmosphere, and the peripheral portions are sealed together to form a vacuum envelope 10. Prior to sealing, the front substrate 2 and the rear substrate 4 are sealed in the vacuum atmosphere. A getter layer 30 (low resistance layer), which will be described later, is formed over the entire inner surface so that a high vacuum after the paneling can be maintained.

  In the SED 1, when an image is displayed, a voltage is applied between the element electrodes of the electron-emitting device 16 through the wiring 18 to emit an electron beam from an electron-emitting portion of the arbitrary electron-emitting device 16 and the phosphor screen 12. The electron beam is accelerated by the anode voltage applied to the phosphor screen 12 to irradiate the phosphor screen 12. As a result, the desired phosphor layers R, G, and B are excited to emit light and display an image.

  Here, the soft flash structure of the metal back 14 described above will be described with reference to FIG. FIG. 4 shows a structure in which the metal back 14 is divided into a plurality of island-like regions 14a for each of the phosphor layers R, G, and B (pixels). Here, in order to clarify the illustration, the sizes of the regions 14a and the pixels R, G, and B with respect to the substrate 2 are different from the actual ratio. Further, although FIG. 4 shows an example in which the metal back 14 is divided into island-shaped regions 14a covering the respective pixels, the metal back 14 may be divided into a plurality of regions covering a plurality of pixels. In any case, in the present embodiment, the metal back 14 is divided into a plurality of small regions 14a, and the plurality of regions 14a are connected by a high resistance member 14b.

  The higher the resistance of the high resistance member 14b between the regions 14a, the more the discharge current can be suppressed. On the other hand, an anode voltage drop is caused by the electron beam current for image display. The optimum resistance value of the high-resistance member 14b cannot be uniformly mentioned because the discharge current suppressing effect depends on the structure of the division and the withstand voltage characteristics between the divisions, but is generally a value of 1 kΩ to 10 MΩ.

  By making the metal back 14 have such a soft flash structure, even if a discharge occurs, the metal back 14 is divided into small regions 14a. Therefore, it is possible to limit the discharge current and suppress damage caused by the discharge. In this case, the getter layer 30 deposited on the metal back 14 also needs to be divided into a plurality of small regions so as not to conduct between the divisions of the metal back 14.

  Next, a method of forming the metal back 14 and the getter layer 30 as the low resistance layer according to the first embodiment of the present invention will be described with reference to FIGS. In each figure, (a) shows a schematic plan view in which the inner surface of the front substrate 2 is partially enlarged, and (b) shows a partial perspective view of the front substrate 2. Further, here, the metal back 14 (and the plurality of elongated rib layers 21 (described later) extending in the X direction in the figure and the plurality of elongated uneven layers 22 (described later) extending in the Y direction in the figure. A method of dividing the getter layer 30) into a plurality of island-like regions 14a for each color pixel will be described. Hereinafter, a method for manufacturing the metal back 14 will be described as a representative.

  First, as shown in FIG. 5, the light shielding layer 11 is formed on the inner surface of the front substrate 2, and the high resistance layer 23 is formed on the light shielding layer 11. The high resistance layer 23 functions as the high resistance member 14b described above, and is provided to control the resistance between the regions 14a after the metal back 14 is divided into a plurality of island-like regions 14a as described later. .

  The light shielding layer 11 has a thickness of about 2 [μm], and has a plurality of rectangular openings 11 a that define the color pixel regions R, G, and B of the phosphor layer in a matrix. In the present embodiment, the arrangement intervals of the color pixel regions arranged in the Y direction in the drawing are set to be relatively narrow (about 50 [μm]), and the arrangement intervals of the color pixel regions arranged in the X direction in the drawing are relatively wide. (About 300 [μm]) is set. The plurality of openings 11a are formed using a predetermined mask pattern by, for example, a photolithography method. The light shielding layer 11 is made of a material whose resistivity is one digit higher than that of the high resistance layer 23.

  The high resistance layer 23 has a thickness of about 10 [μm], and uses a mask pattern substantially the same as the light shielding layer 11 having a resistivity of 10 [Ωm] (resistance between divided metal backs of 0.05 to 0.5 [MΩ]). Formed by the conventional photolithography method. That is, the high resistance layer 23 also has a plurality of openings 23 a that overlap the openings 11 a of the light shielding layer 22.

  Next, as shown in FIG. 6, phosphor layers R, G, and B are formed in the plurality of openings 11a and 23a, respectively. The phosphor layers R, G, and B are formed in the corresponding openings 11a and 23a with a thickness of about 10 [μm], respectively, by a printing method. That is, the phosphor layers R, G, and B are formed at substantially the same height as the high resistance layer 23.

  Then, as shown in FIG. 7, a plurality of elongated rib layers 21 are formed on the high resistance layer 23 at a relatively narrow arrangement interval between the phosphor layers R, G, and B adjacent in the Y direction in the drawing. To do. In the present embodiment, each rib layer 21 is formed by a photolithography method, but each rib layer 21 can also be formed by a sandblast method. By using the photolithography method, the rib layer 21 can be formed in a relatively narrow region.

  Each rib layer 21 extends in the X direction in the drawing, is divided between the relatively wide arrays, and has a thickness in a direction away from the front substrate 2. The rib layer 21 is formed of a material having a thickness of about 20 [μm] and a resistivity that is one digit higher than that of the high resistance layer 23. In the present embodiment, the width of the rib layer 21 is set to about 50 [μm], and the rising angle of the side surface with respect to the substrate 2 is an overhanging shape as shown in FIG. It can be divided at the side when filming.

  Further, as shown in FIG. 9, a plurality of elongated irregularities extending in a direction (Y direction in the figure) intersecting the above-described plurality of rib layers 21 on the high resistance layer 23 having a relatively wide arrangement interval. Layer 22 is formed. In the present embodiment, each uneven layer 22 is formed by a printing method so that the divided portions of the rib layer 21 are generally connected.

  Each uneven layer 22 is formed of a material having a thickness of about 10 [μm] and a resistivity that is one digit higher than the resistivity of the high resistance layer 23. In the present embodiment, the width of the uneven layer 22 is set to about 300 [μm]. More specifically, as shown in FIG. 10, the uneven layer 22 is formed by bonding particles 25 of about 0.1 to 10 [μm] with frit glass.

  Since the uneven layer 22 described above is formed at a relatively low cost by a printing method, its positional accuracy has a deviation of about 50 [μm]. On the other hand, since the rib layer 21 is formed by a photolithography method, the positional accuracy thereof has a deviation of about 5 [μm] and can be formed with a relatively high positional accuracy. For this reason, in the present embodiment, after the rib layer 21 is formed, the uneven layer 22 is formed, and the paste of the uneven layer 22 is dammed by the wall surface portion of the rib layer 21, and the pattern is formed with high accuracy without a gap. ing. In addition, the rib layer 21 is formed in a relatively narrow region and the uneven layer 22 is formed in a relatively wide region. However, when the printing accuracy is increased in the future, the rib layer 21 and the uneven layer 22 may be reversed.

  Further, in the above-described embodiment, the rib layer 21 is divided and the uneven layer 22 passing through the divided portion is formed. However, the uneven layer 22 is partially overlapped with the rib layer 21 without being divided. You may make it let it. Furthermore, in the above-described embodiment, the uneven layer 22 is formed after the rib layer 21 is formed. However, the rib layer 21 may be formed after the uneven layer 22 is formed. In this case, the uneven layer 22 may be divided so that the rib layer 21 passes through this divided portion.

  After forming the dividing lines 21 and 22 of the metal back 14 on the inner surface of the front substrate 2 as described above, the front substrate 2 is baked to remove excess components and be cured. At this time, in each structure, there is contraction of about 10 to 20%, but the above-mentioned numerical values describe the shape dimensions after firing.

  Then, the metal back 14 is formed on the inner surface of the front substrate 2 through the dividing lines 21 and 22 described above. The metal back 14 is formed by applying a smooth resin film (not shown) to the entire front substrate 2 and then depositing AL and baking it to remove excess components. Thereafter, the getter layer 30 is directly formed on the metal back 14 through the dividing lines 21 and 22 described above in the vacuum atmosphere of the panel forming process. The total thickness of both is approximately 100 [nm].

  When the metal back 14 and the getter layer 30 (low resistance layer) are formed in this manner, the metal back 14 and the getter layer 30 are divided at the side surfaces of the rib layer 21, and the metal back 14 and the getter layer 30 are formed by the uneven shape on the surface of the uneven layer 22. Since the getter layer 30 is divided, as a result, the metal back 14 and the getter layer 30 are divided into a plurality of island-shaped regions 14a and 30a. As a result, the metal back 14 and the getter layer 30 are divided in both the rib layer 21 and the uneven layer 22, and the discharge current can be suppressed and improved by about one digit with respect to the conventional linear division structure. It was.

  In addition, although the side surface of the rib layer 21 was made into an overhang shape for division, the metal back 14 and the getter layer 30 are divided if the uneven shape of the rib surface is also used if the inclination angle is large even if it is not overhang shape. be able to. In this case, the rising angle of the side surface with respect to the front substrate 2 is desirably 45 degrees or more.

  As described above, according to the present embodiment, the metal back 14 and the getter layer 30 can be reliably and easily divided into the plurality of island-shaped regions 14a and 30a, and the resistance value between the regions 14a and 30a is substantially designed. Can be on the street. For this reason, the electrical characteristics of the metal back 14 and the getter layer 30 can be stabilized, damage due to discharge can be suppressed, luminance unevenness can be prevented, and a highly reliable display device can be provided.

  In addition, according to the present embodiment, the rib layer 21 is formed by a photolithography method advantageous for high-definition patterning, and the uneven layer 22 is formed by a relatively inexpensive printing method, so that the metal back 14 and the getter layer 30 are soft. In realizing the flash structure, it is excellent in mass productivity and can reduce the manufacturing cost of the SED.

  Next, a dividing structure and a dividing method of the metal back 14 and the getter layer 30 according to the second embodiment of the present invention will be described with reference to FIG. 11 and FIG. The present embodiment is characterized in that an altered layer 40 for altering the metal back 14 is provided on the front substrate 2 side of the uneven layer 22 described above. Therefore, here, the same reference numerals are given to components that function in the same manner as in the first embodiment described above, and a detailed description thereof will be omitted.

  In this embodiment, after the rib layer 21 of the first embodiment described above is formed on the high resistance layer 23 having a relatively narrow arrangement interval as shown in FIG. 7, as shown in FIG. The altered layer 40 was formed in a relatively wide area on the high resistance layer 23 so as to pass through the divided portions of the rib layer 21. In the present embodiment, the altered layer 40 is formed with a width of about 300 [μm] by, for example, a printing method using ammonium phosphate.

  After that, the metal back 14 is formed over the entire area of the front substrate 2 through the rib layer 21 and the altered layer 40, and the metal back 14 is oxidized and altered at the site of the altered layer 40 by firing. The island-shaped region 14a was electrically divided. That is, at this time, the metal back 14 is physically divided by the side surfaces of the rib layer 21 and chemically and electrically divided at a portion overlapping the altered layer 40.

  Thereafter, as shown in FIG. 12, the above-described uneven layer 22 is formed so as to overlap with the portion of the metal back that has been altered in the portion that overlaps the altered layer 40. Then, similarly to the first embodiment, the getter layer 30 is formed through the rib layer 21 and the uneven layer 22. Thereby, the getter layer 30 is also divided into a plurality of island-shaped regions.

  As described above, also in the present embodiment, the metal back 14 and the getter layer 30 can be reliably divided into a plurality of island-like regions, and the discharge current is sufficiently suppressed, as in the first embodiment described above. it can. In addition, according to the present embodiment, when forming a relatively thick metal back 14 having a film thickness exceeding 50 [nm], the metal back 14 can be more reliably divided. In other words, the deteriorated layer 40 is formed before the uneven layer 22 is formed, and the metal back 14 is electrically separated in advance by the deteriorated layer 40, so that the relatively thick metal back 14 is formed. Even if it exists, it can divide reliably in the desired site | part.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, you may delete some components from all the components shown by embodiment mentioned above. Furthermore, you may combine the component covering different embodiment suitably.

  For example, in the above-described embodiment, the case where the metal back 14 and the getter layer 30 are divided into a plurality of island-shaped regions as the low resistance layer has been described. However, the metal back 14 and the getter layer 30 may be at least one, and are not necessarily limited. There is no need to have both. For example, when the degree of vacuum in the vacuum envelope 10 can be maintained at a desired value by other means such as a sputter ion pump, the getter layer 30 is not an essential configuration. Further, if the getter layer 30 has the function of the metal back 14 to function as an anode electrode and can function as a fluorescent reflecting member, the metal back 14 is not an essential configuration.

1 is an external perspective view showing a vacuum envelope of an SED according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the vacuum envelope of FIG. 1 cut along line II-II. The partial expanded sectional view which expands and shows the cross section of FIG. 2 partially. The schematic diagram for demonstrating the soft flash structure which divided | segmented the metal back of the phosphor screen of a front substrate inner surface into island shape. The partial enlarged plan view (a) and partial enlarged perspective view (b) for demonstrating the process which manufactures the parting structure of the low resistance layer based on 1st Embodiment of this invention. The partial enlarged plan view (a) and partial enlarged perspective view (b) for demonstrating the process which manufactures the parting structure of the low resistance layer based on 1st Embodiment of this invention. The partial enlarged plan view (a) and partial enlarged perspective view (b) for demonstrating the process which manufactures the parting structure of the low resistance layer based on 1st Embodiment of this invention. The partial expanded sectional view which expands and shows the rib layer of FIG. 7 partially. The partial enlarged plan view (a) and partial enlarged perspective view (b) for demonstrating the process which manufactures the parting structure of the low resistance layer based on 1st Embodiment of this invention. The partial expanded sectional view which expands and shows the uneven | corrugated layer of FIG. 9 partially. The partial enlarged plan view (a) for demonstrating the process which manufactures the division structure of the low resistance layer based on 2nd Embodiment of this invention, and a partial enlarged perspective view (b). The partial enlarged plan view (a) for demonstrating the process which manufactures the division structure of the low resistance layer based on 2nd Embodiment of this invention, and a partial enlarged perspective view (b).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... SED, 2 ... Front substrate, 4 ... Back substrate, 6 ... Side wall, 8 ... Spacer, 10 ... Vacuum envelope, 12 ... Phosphor screen, 14 ... Metal back, 14a ... Area | region, 14b ... High resistance member, DESCRIPTION OF SYMBOLS 16 ... Electron emission element, 18 ... Wiring, 21 ... Rib layer, 22 ... Uneven layer, 23 ... High-resistance layer, 25 ... Particle, 30 ... Getter layer, 40 ... Alteration layer, R, G, B ... Phosphor layer

Claims (14)

A front substrate having a large number of phosphor layers and a low resistance layer on the inside and a back substrate having a large number of electron-emitting devices on the inside face each other at a predetermined interval to form a vacuum atmosphere, and the phosphor layer and the low resistance layer are In the display device having a higher potential than the electron-emitting device,
The display device according to claim 1, wherein the low-resistance layer is electrically divided into a plurality of island-shaped regions by an elongated rib layer protruding in the thickness direction of the front substrate and an elongated uneven layer having a surface uneven.   The display device according to claim 1, wherein the low resistance layer includes at least one of a metal back and a getter layer.   3. The display device according to claim 2, wherein the plurality of phosphor layers are arranged in a matrix, the rib layer is provided in a narrower arrangement interval, and the uneven layer is provided in a wider one.   4. The display device according to claim 1, wherein the protruding height of the rib layer is 10 μm or more. 5.   4. The display device according to claim 1, wherein a side surface of the rib layer rises at an angle of 45 degrees or more with respect to the front substrate. 5.   The display device according to any one of claims 1 to 3, wherein the rib layer and the uneven layer have portions that overlap each other.   4. The display device according to claim 1, wherein the rib layer is divided at a portion intersecting with the uneven layer. 5.   The display device according to claim 1, wherein the uneven layer is divided at a portion intersecting with the rib layer.   The display device according to claim 2, wherein an alteration layer for chemically altering the metal back is provided on the front substrate side of the uneven layer.   The display device according to claim 9, wherein the uneven layer is formed so as to overlap with a portion of the metal back that has been altered by the altered layer. A front substrate having a large number of phosphor layers and a low resistance layer on the inside and a back substrate having a large number of electron-emitting devices on the inside face each other at a predetermined interval to form a vacuum atmosphere, and the phosphor layer and the low resistance layer are In the manufacturing method of the display device having a higher potential than the electron-emitting device,
A dividing layer forming step of forming an elongated rib layer protruding in the thickness direction inside the front substrate and an elongated uneven layer extending in a direction intersecting the rib layer;
Forming the low-resistance layer on the inside of the front substrate through the rib layer and the uneven layer, and electrically dividing the low-resistance layer into a plurality of island-shaped regions by the rib layer and the uneven layer Process,
A method for manufacturing a display device, comprising:   The method for manufacturing a display device according to claim 11, wherein, in the dividing layer forming step, the rib layer is formed by a photolithography method.   12. The method for manufacturing a display device according to claim 11, wherein in the dividing layer forming step, the rib layer is formed by a sandblast method. The low resistance layer includes a metal back and a getter layer,
Before forming the uneven layer in the dividing layer forming step, an altered layer for altering the metal back is formed at a position where the uneven layer is formed, and then the metal back is formed via the rib layer and the altered layer. And forming the uneven layer overlying the altered metal back portion, and then forming the uneven layer through the uneven layer and the rib layer. The method for manufacturing a display device according to claim 11, wherein a film is formed.

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