KR20080111959A - Manufacturing method and apparatus for display device - Google Patents

Abstract

A manufacturing method of display device capable of reducing crack of substrate by laser irradiation and apparatus thereof are provided to disperse a thermal stress of a substrate by a local laser irradiation by supplying a heat on a substrate and irradiating a laser on seal pattern. A manufacturing method of display device capable of reducing crack of substrate by laser irradiation comprises the following steps: a step for coating a seal pattern on a first substrate(S1); a step for drying the seal pattern(S3); a step for sintering the seal pattern(S5); a step for arranging a second substrate including a pixel array facing to the first substrate in between the seal patterns(S7); and a step for sealing a space between the second substrate and the first substrate by irradiating the laser on the seal pattern after heating the first substrate and the second substrate(S9).

Description

Manufacturing method and device for display device {Manufacturing method and Apparatus for display device}

1 is a view showing an upper substrate and a lower substrate bonded by a seal pattern.

2 is a diagram illustrating a process of sealing a pixel area with a seal pattern.

3 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention.

4A through 4D are diagrams for describing a method of manufacturing a display device according to an exemplary embodiment of the present invention illustrated in FIG. 3 step by step.

5A and 5B illustrate an apparatus for manufacturing a display element for simultaneously performing substrate heating and laser irradiation.

6 illustrates an example of a display device manufactured through a method and an apparatus for manufacturing a display device according to an exemplary embodiment of the present invention.

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

41, 45: substrate 43: seal pattern

40: pixel array 51: laser irradiation apparatus

55: laser 57: radiant heat

59: vacuum chamber 151, 153: heating means

The present invention relates to a method and apparatus for manufacturing a display element. In particular, the present invention relates to a method and an apparatus for manufacturing a display element which can improve a phenomenon in which a crack occurs in a substrate by local laser irradiation.

The display device market has been rapidly changing, focusing on lightweight flat panel displays (hereinafter referred to as "FPDs") instead of the conventional CRT (Cathode-Ray Tube). The FPD includes a liquid crystal display (LCD), a plasma display panel (PDP), an organic electroluminescence display (OLED), and the like.

The FPD includes forming a pixel array on at least one surface of the upper substrate and the lower substrate, and then sealing the space between the upper substrate and the lower substrate. Sealing the space between the upper substrate and the lower substrate is performed by bonding the upper substrate and the lower substrate in a seal pattern such that the pixel array forming surfaces of the upper substrate and the lower substrate face each other.

1 is a view showing the upper substrate 5 and the lower substrate 1 bonded by the seal pattern 3.

Referring to FIG. 1, the seal pattern 3 is bonded to the upper substrate 5 and the lower substrate 1 to seal a space between the upper substrate 5 and the lower substrate 1. Here, the pixel array constituting the display element is formed on the inner surface of at least one of the upper substrate 5 and the lower substrate 1.

The pixel array includes pixel cells for implementing an image and signal lines for driving the pixel cells. The region in which the pixel array is formed is divided into a pixel region P1 in which pixel cells are disposed and a pad region P3 in which the pad portion 6 is formed.

The pixel region P1 includes a plurality of pixel cells for implementing an image. The configuration of the pixel cell may be variously designed according to the type of display element to be implemented.

The pad region P3 is an area where the pad terminal 6 connected to the driving circuit portion is formed, and is exposed to the outside so as to be connected to the driving circuit portion later. The pad terminal 6 is connected to the signal line of the pixel region P1 to supply driving signals from the driving circuit section to the pixel cells.

The seal pattern 3 may include a space between the upper substrate 5 and the lower substrate 1, that is, a seal pattern forming region that is an edge of the upper substrate 5 and the lower substrate 1 to seal the pixel region P1. P2) is formed. The seal pattern 3 prevents oxygen and moisture from the outside from penetrating into the pixel region P1.

2 is a diagram illustrating a process of sealing the pixel region P1 through the seal pattern 3.

The seal pattern 3 is formed by aligning the upper substrate 5 and the lower substrate 1 with the seal pattern 3 therebetween to seal the pixel region P1, and then melting and curing the seal pattern 3. It is bonded to the lower substrate 1.

Melting and curing of the seal pattern 3 are performed by irradiating the laser 7 locally to the seal pattern formation region P2 as shown in FIG. 2 in order not to damage the pixel array. In particular, in the case where the pixel array includes an organic material susceptible to high temperature, such as an organic light emitting display device, it is not the laser 7 irradiated to the pixel region P1 but locally irradiated to the seal pattern formation region P2. Is associated with improved reliability.

Local irradiation of the laser 7 is possible by moving the stage supporting the laser head 9 or the substrates 1, 5 in the direction of the arrow. In this process, the laser 7 has the advantage of being irradiated to the seal pattern forming region P2 by bypassing the pixel region P1, but excessively heats only a portion of the substrates 1 and 5. As such, heat excessively concentrated in the seal pattern forming region P2 causes excessive expansion of the substrates 1 and 5 corresponding to the seal pattern forming region P2. On the other hand, the deformation of the substrates 1 and 5 corresponding to the regions P1 and P3 to which the laser 7 is not irradiated is significantly smaller than that in the seal pattern formation region P2. As a result, cracks occur in the substrates 1 and 5 as shown in region A due to stress caused by excessive heat concentration in the seal pattern forming region P2. The cracks of the substrates 1 and 5 cause problems of the pixel arrays formed on the substrates 1 and 5, thereby lowering the reliability of the display device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a display device capable of improving a phenomenon in which a crack occurs in a substrate by local laser irradiation, and a manufacturing apparatus therefor.

In order to achieve the above object, a method of manufacturing a display device according to an embodiment of the present invention comprises the steps of applying a seal pattern on the first substrate; Drying the seal pattern; Plasticizing the seal pattern; Aligning a second substrate including a pixel array to face the first substrate with the seal pattern therebetween; And heating the first substrate and the second substrate and simultaneously sealing a space between the first substrate and the second substrate by irradiating a laser to the seal pattern.

The pixel array includes an organic light emitting layer.

The applying of the seal pattern to the first substrate is performed in a state where a thin film pattern corresponding to the pixel array is formed on the first substrate.

The seal pattern includes frit glass.

In the sealing of the space between the first substrate and the second substrate, the temperature for heating the first substrate and the second substrate is 120 ° C. or less.

Sealing the space between the first substrate and the second substrate includes the step of introducing into a vacuum chamber having a laser device for irradiating the laser and heating means for heating the first and second substrates.

Plasticizing the seal pattern includes heating the first substrate and irradiating a laser to the seal pattern.

In addition, the apparatus for manufacturing a display device according to an embodiment of the present invention comprises a vacuum chamber into which a substrate including a seal pattern is injected; Heating means for applying heat to the substrate in the vacuum chamber; And a laser irradiation part for irradiating a laser to the seal pattern in the vacuum chamber.

The heating means includes a heating wire embedded in the outer wall of the vacuum chamber.

The heating means comprises a halogen heater mounted inside the vacuum chamber.

Other objects and advantages of the present invention other than the above object will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 3 to 6.

3 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the present invention. 4A through 4E are diagrams for describing a method of manufacturing the display device illustrated in FIG. 3 step by step.

Referring to FIG. 3, a method of manufacturing a display device according to an exemplary embodiment of the present invention may include applying a seal pattern to a first substrate (hereinafter referred to as “S1”), drying a seal pattern (hereinafter referred to as “S3”), and sealing Pattern plasticity (hereinafter referred to as "S5"), second substrate alignment (hereinafter referred to as "S7"), and substrate heating to seal the space between the first substrate and the second substrate by irradiating a laser with the seal pattern. A step (hereinafter referred to as "S9").

The method of manufacturing the display device according to the embodiment of the present invention described above may be applied to any known display device formed by bonding two substrates, but is preferably applied to an organic light emitting display device. For example, the method of manufacturing the display device according to the exemplary embodiment of the present invention may be applied to a liquid crystal display device, a plasma display panel, and the like. Since the liquid crystal display and the plasma display panel do not include an organic light emitting layer that is vulnerable to high temperatures, such as an organic light emitting display, using laser equipment in step S9 may be inefficient in terms of manufacturing cost and yield. Accordingly, the manufacturing method of the display device according to the embodiment of the present invention is preferably applied to the organic light emitting display device in consideration of the manufacturing cost and yield. Description of the organic light emitting display will be described later with reference to FIG. 6.

Hereinafter, a method of manufacturing a display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 4A to 4D.

As shown in FIG. 4A, the seal pattern 43 is applied to the edge of the first substrate 41 through S1. At this time, the seal pattern 43 is a paste and may be applied to a desired area by a dispensing or screen printing method. In addition, the seal pattern 43 includes frit glass having good adhesion with glass in consideration of the fact that a glass having high heat resistance is mainly used as a substrate of the display element. In addition, the seal pattern 43 includes a solvent in order to be in a paste state advantageous for the coating process. The solvent includes a binder to improve the adhesion of the frit glass in powder state.

In operation S1, a thin film pattern may be formed on the first substrate 41 according to the design structure of the display device to be formed. The thin film pattern formed on the first substrate 41 is a pattern corresponding to the pixel array formed on the second substrate to be bonded in a subsequent process, and preferably does not include an organic material in consideration of step S5, which is a subsequent process.

Subsequently, as illustrated in FIG. 4B, the water, the solvent, the binder, and the gas in the seal pattern 43 are removed through steps S3 and S5. Step S3 may be performed at a temperature of about 100 ° C. for about 10 minutes to remove moisture and solvents, and step S5 may be performed at a temperature of 300 ° C. or higher in a nitrogen atmosphere. When the specific steps S3 and S5 proceeds may be set in various ways depending on the material contained in the seal pattern 43.

Thereafter, as illustrated in FIG. 4C, the second substrate 45 is aligned with the seal pattern 43 interposed therebetween in step S7. At this time, the pixel array 40 is formed on the second substrate 45. The pixel array formed on the second substrate 45 includes a plurality of pixel cells including an organic emission layer and pad terminals for applying a driving signal to the pixel cells. In operation S7, the pixel area in which the pixel cells are formed may be disposed in an inner space provided by the first substrate 41, the seal pattern 43, and the second substrate 45, and the pad area in which the pad terminal is formed may be exposed to the outside. Are arranged to be. The exposed pad terminal is later connected to the driving circuit.

Thereafter, as shown in FIG. 4D, the seal pattern 43 is melted and cured through the step S9 to be bonded to the first substrate 41 and the second substrate 45, thereby forming the first substrate 41 and the second substrate. The space between 45, i.e., the pixel region, is sealed. According to the exemplary embodiment of the present invention, the laser 55 is locally irradiated to the region where the seal pattern 43 is formed when the pixel region is sealed, and radiant heat 57 is applied to the first substrate 41 and the second substrate 45. All. Accordingly, the thermal expansion of the first and second substrates 41 and 45 corresponding to the portion to which the laser 55 is irradiated, and the first and second substrates 41 and 45 corresponding to the portion to which the laser 55 is not irradiated. The difference in thermal expansion is reduced. That is, in the method of manufacturing the display device according to the exemplary embodiment of the present invention, the region of the seal pattern 43 is formed by irradiating the seal pattern 43 with the laser 55 and heating the first and second substrates 41 and 45. And the thermal stresses applied to the first and second substrates 41 and 45 corresponding thereto. Accordingly, the method of manufacturing the display device according to the exemplary embodiment of the present invention may improve the reliability of the display device manufacturing process by improving a phenomenon in which cracks occur in the first and second substrates 41 and 45.

The above-described step S9 is performed in the vacuum chamber 59. In the vacuum chamber 59, the stage 53 for mounting the substrates 41 and 45, the heating means for applying the radiant heat 57 to the substrates 41 and 45, and the laser pattern 55 are irradiated to the seal pattern 43. The laser device 51 is provided. The first and second substrates 41 and 45 are fixed to a jig or the like mounted on the stage 53. The temperature of the heat 57 applied by the heating means, that is, the temperature applied to the first and second substrates 41 and 45, is preferably 120 ° C. or lower so as not to damage the organic material included in the pixel array 40. . On the other hand, the temperature applied to the seal pattern 43 by the laser 55 may be variously set according to the type of material constituting the seal pattern 43.

Irradiation of the laser at the same time as the heating of the substrate may be applied in the step S5. The step S5 may be performed in a vacuum oven in a nitrogen atmosphere as described above, but may be performed by irradiating the seal pattern 43 with a laser. In the exemplary embodiment of the present invention, since the crack is generated on the substrate by the local laser irradiation, when the step S5 is to be performed through the laser irradiation, the first substrate 41 simultaneously with the laser irradiation as described above with reference to FIG. 4D. Is preferably heated.

5A and 5B are views showing an apparatus for manufacturing a display element for simultaneously performing substrate heating and laser irradiation.

5A and 5B, the apparatus 50 for manufacturing a display element includes a vacuum chamber 59, a heating means 151 or 153, and a laser irradiation device 51 as described above with reference to FIG. 4D.

The vacuum chamber 59 maintains a degree of vacuum so that gas from the outside does not penetrate into the pixel area while the seal pattern 43 is cured. The substrates 41 and 45 aligned with the seal pattern 43 are introduced into the vacuum chamber 59. The injected substrates 41 and 45 are seated on the stage 53 in the vacuum chamber 59. The stage 53 is equipped with fixing means such as a jig to fix the substrates 41 and 45.

Heating means are embedded in the vacuum chamber 59 to apply heat 57 to the substrates 41, 45. The heating means may include a hot wire 151 on the outer wall of the vacuum chamber 59 as shown in FIG. 5A to evenly transfer the heat 57 to the substrates 41 and 45. The heating means can also be formed by mounting a halogen heater 153 in the vacuum chamber 59 as shown in FIG. 5B to evenly transfer heat 57 to the substrates 41 and 45.

The laser irradiation device 51 is mounted inside the vacuum chamber 59 to irradiate the laser 55 to the seal pattern 43 forming region.

The present invention may be applied to any known display device including two substrates bonded with a seal pattern therebetween, but may be applied to an organic light emitting display device as shown in FIG. 6 in consideration of manufacturing cost and yield. It is preferable.

Referring to FIG. 6, the organic light emitting display device includes a first substrate 41 facing the second substrate 45 and the second substrate 45 on which the pixel array 40 is formed, a first substrate 41, and A seal pattern 43 for sealing the pixel region P1 between the second substrates 45 is provided.

The pixel array 40 of the organic light emitting display device includes thin film transistors T, a first electrode 61, an organic emission layer 63, and a second electrode 65.

The organic light emitting layer 63 includes an electron injection layer, an electron transport layer, a light emitting layer, a hole injection layer, and an electron transport layer. The emission layer includes an organic material emitting red (R), green (G), and blue (B) colors to implement the pixel.

When a voltage is applied to the first electrode 61 and the second electrode 65 of the organic light emitting display device, electrons generated from the second electrode 65 may form an electron injection layer and an electron transport layer of the organic light emitting layer 63. Move toward the emitting layer through. In addition, holes generated from the first electrode 61 move toward the light emitting layer through the hole injection layer and the hole transport layer of the organic light emitting layer 63. Accordingly, in the light emitting layer, light is generated by collision and recombination of electrons and holes supplied from the electron transporting layer and the hole transporting layer, and the light is emitted to the outside through the first electrode 61 to display an image. In addition, although not shown in the drawing, an absorbent for blocking moisture that may flow from the outside may be fixed to the inner surface of the second substrate 45 by a semi-permeable tape.

In FIG. 6, the pixel array 40 is formed only on the second substrate 45. However, the first electrode 61, the organic emission layer 63, and the second electrode 65 may be formed on the second substrate 45. The third electrode connected to the thin film transistor T and the thin film transistor T may be formed on the first substrate 41. In this case, the first substrate 41 may further include a thin film pattern including a third electrode and a connection pattern. The connection pattern is formed between the third electrode and the second electrode 65 to connect the third electrode and the second electrode 65.

As described above, the method and apparatus for manufacturing a display device according to an exemplary embodiment of the present invention can disperse thermal stress of a substrate by local laser irradiation by applying a laser to the seal pattern and applying heat to the substrate. Accordingly, the method and apparatus for manufacturing a display device according to an exemplary embodiment of the present invention can improve the phenomenon of cracking on a substrate due to thermal stress while bonding the seal pattern to the substrate without damaging the pixel array by local laser irradiation. Can be. As a result, the manufacturing method and apparatus of the display device according to the embodiment of the present invention can improve the reliability of the display device.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (10)

Applying a seal pattern to the first substrate; Drying the seal pattern; Plasticizing the seal pattern; Aligning a second substrate including a pixel array to face the first substrate with the seal pattern therebetween; And And heating the first substrate and the second substrate and sealing the space between the first substrate and the second substrate by irradiating a laser to the seal pattern. The method of claim 1, And the pixel array comprises an organic light emitting layer. The method of claim 1, Applying the seal pattern to the first substrate is And a thin film pattern corresponding to the pixel array is formed on the first substrate. The method of claim 1, And the seal pattern comprises frit glass. The method of claim 1, Sealing the space between the first substrate and the second substrate The temperature for heating the first substrate and the second substrate is 120 ℃ or less method for manufacturing a display element. The method of claim 1, Sealing the space between the first substrate and the second substrate And throwing into a vacuum chamber including a laser device for irradiating the laser and heating means for heating the first and second substrates. The method of claim 1, Plasticizing the seal pattern is And heating the first substrate and irradiating a laser to the seal pattern. A vacuum chamber into which a substrate including a seal pattern is inserted; Heating means for applying heat to the substrate in the vacuum chamber; And And a laser irradiator for irradiating a laser to the seal pattern in the vacuum chamber. The method of claim 8, The heating means And a heating wire embedded in the outer wall of the vacuum chamber. The method of claim 8, The heating means And a halogen heater mounted inside the vacuum chamber.

Images