TWI539589B - Display device packaging method and device - Google Patents

Description

Display device packaging method and device

The present invention relates to the field of packaging technology for display devices, and in particular, to a packaging method and device for a display device.

At present, in the low-melting frit packaging process of the OLED, a sintering process is included, that is, after coating a circle of a frit paste on the substrate, the solvent in the glass paste layer is evaporated by a baking process. The glass paste is cured.

However, since the flatness of the upper surface of the glass paste layer cannot be ensured when the glass paste is applied, the morphology of the glass paste layer after the baking process is shaped, that is, when the glass paste layer formed by the coating has a rough upper surface On the surface, after the baking process, the upper surface of the cured glass paste layer is also rough, which will reduce the sealing of the packaging process and further affect the device during the laser sealing process and other subsequent packaging processes. Performance and product yield.

The first figure is a schematic structural view of a conventional packaging process. As shown in the first figure, the hard substrate 1 is provided with a device region 2, and the periphery of the device region 2 is coated with a glass paste 3, which is difficult to control due to the coating process. The flatness of the upper surface of the glass paste 3, which in turn causes the upper surface of the glass paste 3 formed by the coating to be rough; after the baking process, the shape is not changed by the baking process, that is, the prepared glass The upper surface of the paste layer has a rough structure as shown in the first figure. When the device region 2 is subsequently packaged by the cover 4, the upper surface of the glass paste layer 3 is uneven, so that the cover 4 and the glass paste layer 3 are If the contact surface is not tightly bonded (with a slight gap), the sealing performance of the subsequent packaging process will be reduced, and the external water, oxygen and other impurities will easily penetrate into the device region 2, which will reduce the performance of the product. rate.

Chinese Patent (Publication No.: CN 102436999 A) discloses a package structure and a packaging method of a display device, comprising a glass frame, a glass frit, and at least one coil combination And a glass substrate. The glass frame has a joint surface, the glass frit is correspondingly disposed on the joint surface, the coil combination is disposed between the joint surface and the glass frit; the glass substrate is coated on the glass frame, and the glass frit is located between the glass frame and the glass substrate . However, the display device package structure disclosed in the invention mainly provides a closed coil at a joint between the frame of the display device and the glass substrate, and utilizes a high-frequency electromagnetic induction principle to cause a closed coil sensing between the frame and the glass substrate. Warming up to carry out the encapsulation process. However, in the technical solution described in this patent document, when high-frequency electromagnetic induction is used to induce temperature rise of the closed coil between the frame and the glass substrate, the flatness of the surface of the glass frit cannot be ensured, and the sealing performance after sealing can be reduced.

Chinese Patent (Publication No.: CN 19537199 B), discloses an organic light emitting display device and a method of fabricating the same, comprising: a first substrate; an organic light emitting pixel array formed on the substrate; and a second substrate opposite to the first substrate . a frit seal disposed between the first substrate and the second substrate while surrounding the array, wherein the frit seal includes an inner surface facing the array; a film structure comprising one or a plurality of layered films, wherein the film structure includes a portion disposed between the second substrate and the array, the film structure substantially filling a space between the second substrate and the array and Also contacting the inner surface of the second substrate and the top surface, wherein the film structure also substantially contacts an entire portion of the inner surface of the frit seal, wherein contacting the frit seal The film structure of the inner surface comprises a resin material, wherein the frit seal further comprises an outer surface facing away from the array, wherein the same resin material is formed on an outer surface of the frit seal On the whole part. In the technical solution described in the patent document, the thickness and width of the sealing member in the direction parallel to the surface of the top substrate or the bottom substrate are designed to be in contact with the bottom substrate and the top substrate to connect the top plate and the bottom plate. A tight joint is formed between them, but the sealing property of the package is not well ensured in the packaging process, which causes external water and oxygen to enter the device, thereby affecting product performance.

An organic electroluminescent display device and a method of fabricating the same are disclosed in US Patent Publication No. US 2008/0001533, which comprises: preparing a first substrate; forming a display element on the first substrate; preparing a second substrate; Or applying a sealant to the periphery of the second substrate, and bonding the first substrate to the second substrate; and curing the sealant, the sealant comprising a glass powder and a light-to-heat conversion agent, the display element a first electrode and a second electrode disposed on the first substrate and having different work functions; and an organic layer disposed between the first electrode and the second electrode and having an organic light-emitting layer, further in the second substrate Includes moisture absorbent. The frit glass can reduce the moisture and oxygen transmission rate by preventing the organic electroluminescent diode from being thermally decomposed during the curing process to improve the sealing property. The patent document describes a technical solution for encapsulating two substrates by frit glass, which can increase the life and reliability of the organic electroluminescent display, but the technical solution does not ensure good device well after the packaging process. The sealing property causes external water and oxygen to enter the inside of the device and affect device performance.

The invention provides a method and a device for packaging a display device. After applying a glass paste on a substrate, a low-temperature baking process is performed to evaporate a part of the solvent in the glass paste to form a semi-cured glass paste, and continue to use one The flat surface plate flattens the surface of the semi-cured glass paste to improve the flatness of the upper surface of the glass paste, and finally evaporates the remaining solvent in the glass paste by high-temperature baking to form a flat surface. The fully cured glass paste ensures the sealing of the cover and the glass paste during subsequent packaging methods, thereby improving the performance and yield of the packaged device.

The technical solution adopted by the present invention is: a packaging method of a display device, which is applied to a rigid substrate having a device region, wherein the method comprises the steps of: coating a surface of the substrate with a glass paste layer, the glass paste layer Forming a closed glass paste layer around the device region; heating the glass paste layer for the first time, and planarizing the upper surface of the glass paste layer; performing the glass paste layer a second time The glass paste layer is heated and cured.

Preferably, the display device is packaged in a temperature range of 80 ° C to 120 ° C using the first heating step.

Preferably, the display device is packaged in which the temperature of the second heating step is higher than the temperature of the first heating step.

Preferably, the display device is packaged, wherein the second heating step has a temperature ranging from 100 ° C to 150 ° C.

Preferably, the display device is packaged in which the upper surface of the glass paste layer is planarized by a press plate.

Preferably, the display device of the display device, wherein the pressure plate is provided with a linkage device for controlling the pressure plate to enter the upper surface of the glass paste layer Line flattening.

Preferably, the display device of the display device, wherein the surface of the platen contacting the glass paste layer is provided with a gasket, and the height of the gasket is smaller than the thickness of the glass paste layer.

Preferably, the display device is packaged, wherein the spacer has a height of 5 um to 30 um.

Preferably, the display device is packaged, wherein an adhesion between the lower surface of the platen and the glass paste layer is less than an adhesion between the glass paste layer and the hard substrate.

A packaging device for a display device is applied to a hard substrate having a device region, and a closed glass paste layer is disposed on an upper surface of the hard substrate surrounding the periphery of the device region, wherein the packaging device includes a pressing plate, The pressure plate is disposed directly above the glass paste layer by a linkage device, the linkage device controls the pressure plate to planarize an upper surface of the glass paste layer; and the glass paste layer is flattened by using the pressure plate In the chemical process, the glass paste layer is in a semi-cured state.

Preferably, the packaging device of the display device, wherein the adhesion between the glass paste layer and the hard substrate is greater than the adhesion between the lower surface of the pressure plate and the glass paste layer.

Preferably, the display device of the display device, wherein a surface of the platen contacting the glass paste layer is provided with a liner having a height smaller than a thickness of the glass paste layer.

Preferably, the display device of the display device, wherein the pad height is 5 um to 30 um.

Since the present invention adopts the above technical solution, when the display device is packaged, the surface of the glass paste is planarized, thereby improving the quality of the product in the subsequent packaging method, thereby avoiding the infiltration of water and oxygen into the device. Product defects, improve product yield.

1‧‧‧hard substrate

2‧‧‧Device area

3‧‧‧ glass paste layer

3A‧‧‧Semi-cured glass paste layer

3B‧‧‧A layer of glass paste after flattening

3C‧‧‧cured glass paste layer

4‧‧‧ Cover

5‧‧‧Press

6‧‧‧ cushion

The first figure is a schematic structural diagram of a conventional OLED packaging process; 2 to 6 are flowcharts showing a planarization process of a glass paste layer according to Embodiment 1 of the present invention; and FIG. 7 is a structure for planarizing a glass paste layer by using another press plate in Embodiment 1 of the present invention; FIG. 8 is a schematic structural view of a packaging device of a display device according to Embodiment 2 of the present invention.

The following describes the specific embodiment of the present invention with reference to the accompanying drawings: Embodiment 1: Referring to FIG. 2 to FIG. 6 , the packaging method of the display device of the present application specifically includes the following steps: First, a substrate 1 is provided. (such as a glass substrate or other type of substrate, etc.), and the upper surface of the hard substrate 1 is provided with a device region 2, in which a device such as a TFT transistor (but not limited to a TFT transistor) may be disposed in the device region 2 A ring of glass paste is coated on the upper surface of the hard substrate 1 on the periphery of the region 2 to form a glass paste layer 3A, that is, a structure as shown in the second figure is formed; wherein the glass paste layer 3A forms a closed region around the device region 2 ( The device region 2 is located in the closed region to encapsulate the device region 2, and the height of the glass paste layer 3A is greater than a predetermined height. The set thickness can be set according to different process requirements, and can be 2 -40um, in this embodiment, the height of the glass paste layer 3 is preferably greater than 30um and less than 32um (such as 30.5um, 30.75um, 31um or 31.5um equivalent), and the width of the glass paste layer 3 is also In a predetermined width, the width of the set may be set according to process requirements, to reserve space for a respective glass paste layer 3 for the subsequent planarization process may be 200-1200um.

In addition, since the glass paste layer 3A is prepared by coating a glass paste on the hard substrate 1, the flatness of the upper surface of the coated glass paste cannot be ensured due to the limitation of the process technology, so that the upper surface of the formed glass paste layer 3A has an uneven structure ( Surface having a rough structure), if the glass paste layer 3A having a rough surface is not treated in the subsequent baking process, the surface of the glass paste layer cured by the baking process is also rough, that is, formed after the curing process The flatness of the upper surface of the glass paste layer is poor, which in turn affects the sealing effect of the device, so that external water, oxygen, and the like easily penetrate into the device region 2, thereby reducing device performance and product yield.

Next, the first heating process of the hard substrate 1 coated with the glass paste layer 3A is continued. In this embodiment, the temperature of the first heating process is controlled between 90 ° C and 120 ° C (eg, 90 ° C, The first heating process is performed at a temperature of 100 ° C, 110 ° C or 120 ° C, to evaporate the solvent (such as an organic solvent, etc.) in the glass paste layer 3A, since the temperature of the first heating process is not The temperature at which the glass paste layer 3A is completely cured (the curing temperature of the glass paste is greater than 120 ° C), so the rate of solvent evaporation in the glass paste layer 3A is slow; when a part of the solvent in the glass paste layer 3A is evaporated, the glass The fluidity of the paste layer is lowered, thereby forming a semi-cured glass paste layer 3A, that is, the semi-cured glass paste layer 3A at this time still has a certain plasticity; and since this step is only a heating process to evaporate the glass paste The solvent does not affect the morphology of the glass paste layer, so that the structural pattern formed after the first heating process is the same as the structural pattern shown in the second figure; therefore, the upper surface of the semi-cured glass paste layer 3A Still with Certain roughness.

Thereafter, as shown in the third and fourth figures, the upper surface of the semi-cured glass paste layer 3A is planarized by a pressing plate 5; specifically, the pressing plate 5 is provided with a linkage device (not shown). The linkage controls the platen 5 to planarize the upper surface of the semi-cured glass paste layer 3A. Preferably, the linkage device (such as a robot) is fixedly disposed on the upper surface of the pressure plate 5 to drive the pressure plate 5 to move up and down directly above the glass paste layer 3A, and the lower surface of the pressure plate 5 is provided with a gasket. 6. Since the height of the spacer 6 is the same as the preset height of the above-mentioned glass paste layer 3A, when the interlocking device drives the pressing plate 5 to planarize the upper surface of the semi-cured glass paste layer 3A, since it is semi-cured The thickness of the glass paste layer 3A is greater than the height of the liner 6, and when the upper surface of the semi-cured glass paste layer 3A is in contact with the lower surface of the pressure plate 5, the liner 6 can be combined with the hard substrate 1 when the pressure plate 5 is moved downward. Contact, when the platen 5 planarizes the semi-cured glass paste layer 3A, the liner 6 can prevent the platen 5 from over-extruding the semi-cured glass paste layer 3A, so that the planarized glass paste layer 3B is The thickness meets the process requirements.

Further, since the lower surface of the pressing plate 5 is relatively flat (the flatness of the surface of the pressing plate 5 contacting the glass paste layer 3A is less than a preset value, the preset value may be set according to specific process requirements); In the embodiment of the invention, it is preferable to use, for example, marble having a smooth surface or other hard material having less adhesion to the glass paste layer as the material of the press plate 5. When the planarization process is performed, since the semi-cured glass paste layer 3A has a certain plasticity, when the platen 5 presses the upper surface of the semi-cured glass paste layer 3A, the upper surface of the semi-cured glass paste layer 3A is formed. The uneven rough structure on the upper surface is flattened, thereby lowering the upper surface of the semi-cured glass paste layer 3A Roughness.

Further, as shown in the fourth figure, when the platen 5 presses the upper surface of the semi-cured glass paste layer 3A to perform a planarization process, the semi-cured portion is pressed while the thickness of the semi-cured glass paste layer 3A is lowered. The glass paste layer 3A is extended in the lateral direction, and the thickness and width of the semi-cured glass paste layer 3B after the planarization process are in accordance with the process requirements due to the reserved space for coating the glass paste in the early stage. .

Preferably, the pad 6 has a height of 5 um to 30 um (e.g., 5 um, 10 um, 20 um, 30 um, etc., in a range of values), and in the embodiment of the invention, the pad 6 may be a closed bulge (see The structure shown in the third figure), when the platen 5 is in contact with the glass paste layer 3, the gasket 6 surrounds the periphery of the glass paste layer 3A, and the gasket 6 can also be a groove structure composed of two closed protrusions (see the The structure shown in Figure 7 can be set according to the process requirements (that is, the depth of the groove structure is the same as the preset height, and the width is the same as the preset width), and the pad 6 can also be set to other shapes. The support structure (such as a plurality of columnar structures, etc.), as long as the liner 6 can ensure that the thickness of the glass paste layer after the planarization process is set to a thickness required by the process.

Further, after the planarization process is performed, the linkage device drives the pressure plate 5 away from the planarized glass paste layer 3B, between the lower surface of the pressure plate 5 and the upper surface of the planarized glass paste layer 3B. The adhesion is less than the adhesion between the upper surface of the hard substrate 1 and the lower surface of the planarized glass paste layer 3B, so that the flattened glass paste layer 3B does not adhere to the platen when the platen 5 is moved upward. The lower surface of 5 prevents the flattened glass paste layer 3B from being peeled off from the upper surface of the hard substrate 1.

In this embodiment, the height of the glass paste layer can be controlled by controlling the height of the liner 6 to meet different process production requirements.

Then, using a temperature higher than the temperature of the first heating process, the second heating process is performed (the temperature of the second heating process is preferably higher than the temperature of the first heating process by 40 ° C). The solvent in the planarized glass paste layer 3B is completely removed, so that the glass paste layer 3B is completely cured, thereby obtaining a cured glass paste layer 3C having a flat upper surface, and the thickness of the cured glass paste layer 3C is equal at each position. Its thickness and width also meet the process requirements. In this embodiment, the temperature in the reaction chamber is controlled at 110 ° C to 150 ° C (such as 110 ° C, 130 ° C, 140 ° C, 150 ° C, etc.), and a second heating process is performed to accelerate the flattened glass. The evaporation rate of the remaining solvent in the paste layer 3B is such that the planarized glass paste layer 3B is rapidly solidified to obtain a cured glass paste layer 3C having a flat upper surface and equal thickness at each position, and the step is completed. The structure as shown in the sixth figure is formed later. As shown in the sixth figure, after the second heating process is completed, the glass paste is completely cured, and the upper surface of the prepared cured glass paste layer 3C has been flattened relative to the upper surface of the glass paste layer 3A, thereby enabling The sealing between the glass paste layer and the cover plate in the subsequent packaging method is ensured to improve the performance of the packaged device.

In an embodiment of the invention, preferably, the first heating process and the second heating process are baking processes.

Finally, a subsequent laser encapsulation method is performed to complete the sealing process of the device, and the subsequent process steps are conventional technical means in the art, and are not described herein.

Embodiment 2: FIG. 8 is a schematic structural view of a packaging device of a display device in Embodiment 2; as shown in FIG. 8 , a packaging device for a display device, which is applicable to a rigid substrate 1 having a device region 2 The encapsulation method is performed, and the upper surface of the hard substrate 1 is disposed around the periphery of the device region 2 with a closed glass paste layer 3A; the packaging device includes a pressing plate 5, and the pressing plate 5 is disposed on the glass paste layer 3A through a linkage device. Directly above, the linkage controls the platen to planarize the upper surface of the glass paste layer; when the platen is planarized by the platen, the glass paste layer is semi-cured.

Wherein, the lower surface of the pressure plate 5 is provided with a gasket 6 . Preferably, the gasket 6 has a height of 5 um to 30 um (such as a height within a numerical range of 5 um, 10 um, 20 um, 30 um, etc.); the lower surface of the pressure plate 5 The flatness is set according to the process requirements. In the present embodiment, a flattening process is preferably employed by using a press plate having a smooth lower surface, preferably using a marble having a smooth surface or other hard adhered to the glass paste layer. The material is used as the material of the pressure plate 5; therefore, when the pressure plate 5 moves upward, the glass paste layer does not adhere to the lower surface of the pressure plate 5, and the flattened glass paste layer is prevented from being peeled off the upper surface of the hard substrate 1, thereby ensuring the packaging method. The normal progress.

In summary, since the present invention adopts the above technical solution, in the glass paste package, a part of the solvent in the glass paste is first removed by low-temperature baking evaporation, so that the glass paste is semi-cured to have a certain plasticity, and then a The platen with a smooth lower surface planarizes the glass paste, so that the upper surface of the glass paste tends to be flat. Finally, the remaining solvent in the glass paste is evaporated at a high temperature to completely cure the film and perform subsequent laser encapsulation and sealing processes. . The invention planarizes the glass paste by baking at a low temperature, and finally performs three high-temperature baking process steps to ensure the flatness of the upper surface of the glass paste, and at the same time makes the glass paste meet the production process requirements, so that the device is followed. The sealing method has good sealing and avoids external moisture and Oxygen enters the interior of the device, improving device performance and product yield.

Exemplary embodiments of the specific structure of the specific embodiments are given by way of illustration and the accompanying drawings, and other transitions are possible in accordance with the spirit of the invention. Although the above invention proposes a prior preferred embodiment, these are not intended to be limiting.

Various changes and modifications will no doubt become apparent to those skilled in the <RTIgt; Accordingly, the appended claims are to cover all such modifications and modifications The scope and content of any and all equivalents are intended to be within the scope and spirit of the invention.

1‧‧‧hard substrate

2‧‧‧Device area

5‧‧‧Press

6‧‧‧ cushion

3B‧‧‧flattened glass paste layer

Claims (10)

A method for packaging a display device, applied to a substrate having a device region, comprising the steps of: coating a surface of the substrate with a glass paste layer, the glass paste layer having a first height and a a width, and forming a closed glass paste layer around the device region; first heating the glass paste layer; planarizing the upper surface of the glass paste layer with a press plate, wherein the press plate a surface is disposed on the surface in contact with the glass paste layer, whereby the planarized glass paste layer has a second height and a second width, wherein the second height is less than the first height and Equal to the pad height, the second width being greater than the first width; and heating the glass paste layer a second time and curing the glass paste layer. The method of packaging a display device according to claim 1, wherein the temperature of the first heating step is in the range of 80 ° C to 120 ° C. The method of packaging a display device according to claim 2, wherein the temperature of the second heating step is higher than the temperature of the first heating step. The method of packaging a display device according to claim 3, wherein the temperature of the second heating step ranges from 100 ° C to 150 ° C. The method of packaging a display device according to claim 1, wherein the platen is provided with a linkage device, and the linkage device controls the platen to planarize an upper surface of the glass paste layer. The method of packaging a display device according to claim 1, wherein the spacer has a height of 5 um to 30 um. The method of packaging a display device according to claim 1, wherein the adhesion between the platen and the glass paste layer is less than the adhesion between the glass paste layer and the hard substrate. . A packaging device for a display device is applied to a hard substrate having a device region, and a closed glass paste layer is disposed on an upper surface of the hard substrate surrounding the periphery of the device region, the glass paste layer having a first height and a first width, wherein the packaging device comprises a pressing plate disposed directly above the glass paste layer by a linkage device, the linkage device controlling the pressing plate to an upper surface of the glass paste layer Performing a planarization process; wherein, when the glass paste layer is planarized by the press plate, the glass paste layer is in a semi-cured state, and the surface of the pressure plate that is in contact with the glass paste layer is provided with a liner Thereby flattening The subsequent glass paste layer has a second height and a second width, wherein the second height is less than the first height and equal to the pad height, and the second width is greater than the first width. The packaging device of the display device of claim 8, wherein the adhesion between the glass paste layer and the hard substrate is greater than the adhesion between the pressure plate and the glass paste layer. . The packaging device of the display device according to claim 8, wherein the pad height is 5 um to 30 um.