Preparation method and stripping device of flexible display device

Abstract

The present invention relates to a preparation method and stripping equipment for a flexible display device, the preparation method comprising the following steps: preparing a flexible display device to be stripped on a carrier substrate, the flexible display device to be stripped having a functional area and a non-functional area; destroying the bonding force between the flexible display device to be stripped and the carrier substrate in the functional area to form a non-bonded or partially non-bonded stripping area in the functional area and a contacted and bonded non-stripping area in the non-functional area; cutting the carrier substrate to separate the carrier substrate in the stripping area from the carrier substrate in the non-stripping area, and removing the carrier substrate in the stripping area; cutting the flexible display device to be stripped to separate the functional area from the non-functional area, and removing the non-functional area. In the preparation method of the present invention, due to the presence of the non-stripping area, the flexible display device to be stripped and the carrier substrate will not be relatively displaced, the flexible display device to be stripped will not fall off during transportation, the carrier substrate will not slip, and the transportation reliability is good.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a preparation method and a manufacturing device for a flexible display device. Background Art

[0002] In recent years, the development of flexible display (Flexible Display) and foldable display (Foldable Display) technologies has been rapid. They are the focus of domestic and foreign universities and research institutes, and are also key technologies that display companies and terminal manufacturers are competing to deploy. With the continuous development of production processes and technologies, the forms of flexible displays are becoming more and more diverse. While the screen size is increasing, the display quality is also continuously improving. Terminal manufacturers have also launched flexible and foldable terminal products. Flexible displays use flexible substrate materials as device carrier substrates, and require that the electrode layer, TFT matrix, display device and packaging layer have a certain bending radius to achieve flexibility, including electronic paper, flexible liquid crystal display and flexible organic electroluminescent display devices. Compared with ordinary displays, flexible displays have many advantages: light weight, small size, thinness, and easy to carry; high and low temperature resistance, impact resistance, and earthquake resistance are stronger, and can adapt to a wider working environment; can be rolled, and the appearance is more aesthetically pleasing; the roll-to-roll production process using printing technology is more cost-effective; low power consumption and more energy-saving; organic materials are more green and environmentally friendly.

[0003] At present, flexible display products are mainly produced by S2S (sheet to sheet) production process, with glass substrate as carrier, combined with flexible substrate attachment and removal and other methods. Attachment and removal is to attach the flexible substrate to the hard carrier substrate to prepare the display device, and then peel off the hard substrate after the display device is prepared to take out the flexible display device. This method does not affect the production accuracy of the display device, and the production equipment and process are similar to those of traditional TFT-LCD, and no major adjustments are required, so it is closer to mass production application in the short term. The attachment and removal process can be roughly divided into two categories: one is laser lift-off technology (LLO: Laser Lift-Off), which uses laser to directly act on the interface between the plastic substrate and the carrier, and uses high-energy laser to destroy the bonding force between the plastic substrate and the carrier to separate them; the other is mechanical lift-off technology (MLO: Mechanical Lift-Off), which uses the different bonding forces between the special release layer and the plastic substrate and the carrier, and separates them by cutting and removing the part with strong edge bonding. The laser lift-off process is used in the production of flexible displays and has been mass-produced on flexible OLED mobile phones. However, there are still problems such as low lift-off efficiency, easy falling off of flexible display devices during transportation, and easy slipping of carrier substrates. Summary of the invention

[0004] Based on this, it is necessary to provide a method for preparing a flexible display device with high peeling efficiency and good handling reliability.

[0005] A method for preparing a flexible display device comprises the following steps:

[0006] Preparing a to-be-peeled flexible display device on a carrier substrate, wherein the to-be-peeled flexible display device has a functional area and a non-functional area;

[0007] Destroying the adhesive force between the to-be-peeled flexible display device in the functional area and the carrier substrate to form a peeling area in contact but not bonded or partially not bonded in the functional area and a non-peeling area in contact and bonded in the non-functional area;

[0008] Cutting the carrier substrate to separate the carrier substrate in the peeling area from the carrier substrate in the non-peeling area, and removing the carrier substrate in the peeling area; and

[0009] The flexible display device to be peeled off is cut to separate the functional area from the non-functional area, and the non-functional area is removed.

[0010] The method for preparing a flexible display device of the present invention destroys only the bonding force between the functional area of ​​the flexible display device to be peeled and the carrier substrate when destroying the bonding force between the flexible display device to be peeled and the carrier substrate, thereby forming a peeling area that is in contact but not bonded or partially not bonded in the functional area and a non-peeling area that is in contact and bonded in the non-functional area. Then, by cutting the carrier substrate, removing the carrier substrate in the peeling area, and then cutting the flexible display device to be peeled, the functional area is separated from the non-functional area, and finally removing the non-functional area of ​​the flexible display device to be peeled, a flexible display device with a retained functional area can be obtained. Due to the existence of the non-peeling area, the flexible display device to be peeled and the carrier substrate will not be relatively displaced, the flexible display device to be peeled will not fall off during transportation, and the carrier substrate will not slip, the transportation reliability is good, and the process yield of large-size flexible display devices is effectively improved. It can be understood that when preparing the flexible display device to be peeled on the carrier substrate, the range of each functional layer can be adjusted to adjust the functional area and non-functional area of ​​the flexible display device to be peeled, and then the peeling area and non-peeling area are determined.

[0011] In one of the embodiments, the bonding force is destroyed by shielding the flexible display device to be peeled off in the non-functional area and performing laser scanning on the functional area.

[0012] In one of the embodiments, a matte metal mask is used to shield the flexible display device to be peeled off in the non-functional area.

[0013] In one embodiment, after the step of cutting the carrier substrate and before the step of removing the carrier substrate in the peeling area, the method further includes the following steps:

[0014] The carrier substrate in the non-peeling area is pressed down and bent.

[0015] In one embodiment, when the carrier substrate in the non-peeling area is pressed down and bent, the angle between the plane where the carrier substrate in the bent non-peeling area is located and the plane where the carrier substrate in the peeling area is located is 3° to 5°.

[0016] In one embodiment, the step of cutting the carrier substrate is performed by placing the flexible display device to be peeled off and the carrier substrate on a separation platform, and the flexible display device to be peeled off is located between the carrier substrate and the separation platform;

[0017] Wherein, during the process of cutting the carrier substrate, the separation platform vacuum absorbs the flexible display device to be peeled off from the functional area;

[0018] After the carrier substrate is cut, a pressure roller is used to press down and bend the carrier substrate in the non-peeling area, and the separation platform vacuum absorbs the flexible display device to be peeled off in the non-functional area.

[0019] The present invention also provides a peeling device for peeling a flexible display device to be peeled off on a carrier substrate, wherein the flexible display device to be peeled off has a functional area and a non-functional area, and the peeling device comprises:

[0020] A laser peeling mechanism, wherein the laser peeling mechanism is used to perform laser scanning to destroy the adhesion between the flexible display device to be peeled off in the functional area and the carrier substrate, so as to form a peeling area that is in contact but not bonded or partially not bonded in the functional area and a non-peeling area that is in contact and bonded in the non-functional area;

[0021] A cutting mechanism, wherein the cutting mechanism is used to cut the carrier substrate and the flexible display device to be peeled off;

[0022] A separation platform, the separation platform comprises a main body and an inclined portion connected to the main body, the main body is used to carry the flexible display device to be peeled off and the carrier substrate corresponding to the peeling area, the inclined portion is used to carry the flexible display device to be peeled off and the carrier substrate corresponding to the non-peeling area, and the carrying surface of the inclined portion is an inclined surface inclined toward a side away from the carrying surface of the main body.

[0023] In one embodiment, the stripping device further comprises:

[0024] A shielding mechanism is used to shield the flexible display device to be peeled off and a partial area of ​​the carrier substrate during laser scanning to form the peeling area and the non-peeling area.

[0025] In one embodiment, the main body and the inclined surface are both provided with a plurality of vacuum adsorption holes at intervals, and the distribution density of the vacuum adsorption holes in the inclined surface is greater than the distribution density of the vacuum adsorption holes in the main body.

[0026] In one of the embodiments, the vacuum adsorption holes of the main body are distributed at equal intervals, the diameter of the vacuum adsorption holes of the main body is 0.4-0.6 mm, and the distance between adjacent vacuum adsorption holes is 8 mm-12 mm.

[0027] In one embodiment, the vacuum adsorption holes of the inclined portion are distributed in rows at unequal intervals, and the intervals between adjacent vacuum adsorption holes gradually decrease in a direction away from the main body portion.

[0028] In one embodiment, the stripping device further comprises:

[0029] A manipulator mechanism, the manipulator mechanism comprising a frame and a plurality of adsorbents disposed on the frame, wherein the heights of the plurality of adsorbents are independently adjustable; and / or,

[0030] A pressure roller is used to press down and bend the carrier substrate in the non-peeling area. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the mismatch problem in the flexible binding process;

[0032] Figure 2 A schematic diagram of the problem of flexible display devices falling off during transportation;

[0033] Figure 3 is a schematic diagram of preparing a flexible display device according to an embodiment;

[0034] Figure 4 Schematic diagram of the structure of a manipulator mechanism of an embodiment, A is a top view, B is a side view;

[0035] Figure 5 Schematic diagram of a laser lift-off process according to an embodiment, A is a side view, and B is a top view;

[0036] Figure 6 This is a schematic structural diagram of a separation platform according to an embodiment;

[0037] Figure 7 is a schematic diagram of a carrier substrate cutting process according to an embodiment;

[0038] Figure 8FIG. 4 is a schematic diagram of a carrier substrate removal process according to an embodiment.

[0039] Explanation of the reference numerals: shielding mechanism 10, separation platform 20, main body 21, inclined portion 22, vacuum adsorption hole 23, manipulator mechanism 30, frame 31, adsorption part 32, PCB adsorption area 33, substrate adsorption area 34, pressing roller 40, peeling area 201, non-peeling area 202, carrier substrate 300, flexible substrate 211, water and oxygen barrier layer 212, TFT array 213, device functional layer 214, thin film encapsulation 215, polarizer 216. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below, and preferred embodiments of the present invention are provided. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items. In addition, any method and material similar or equivalent to the described content can be applied to the present invention.

[0042] A method for preparing a flexible display device according to an embodiment of the present invention comprises the following steps S1 to S4:

[0043] S1. Preparing a flexible display device to be peeled off on a carrier substrate, wherein the flexible display device to be peeled off has a functional area and a non-functional area;

[0044] S2, destroying the adhesive force between the to-be-peeled flexible display device and the carrier substrate in the functional area, so as to form a peeling area that is in contact but not bonded or partially non-bonded in the functional area and a non-peeling area that is in contact and bonded in the non-functional area;

[0045] S3, cutting the carrier substrate to separate the carrier substrate in the stripping area from the carrier substrate in the non-stripping area, and removing the carrier substrate in the stripping area;

[0046] S4, cutting the flexible display device to be peeled off to separate the functional area from the non-functional area, and removing the non-functional area.

[0047] The current laser lift-off process is used in the production of flexible OLED displays. There are two main solutions for process development based on the G6 generation production line: 1. First, laser lift-off the G6-sized flexible device as a whole, then divide it according to the panel size, and then perform IC bonding; 2. First, divide the G6-sized flexible device according to the panel size, then perform IC bonding on a single panel, and finally perform laser lift-off on a single panel. However, if Figure 1 As shown, the first process has the mismatch problem of flexible binding. Figure 2 As shown in the figure, in the process from laser scanning to flexible device separation, there is a high risk of falling off during transportation and carrier substrate slippage. Once the G6 size flexible device falls off, all panels are lost and the yield is zero. Although the second process does not have the problem of flexible binding, it is less efficient and there is a risk of flexible devices falling off when a single panel is transported, which seriously affects the process yield.

[0048] The method for preparing a flexible display device of the present invention destroys only the bonding force between the functional area of ​​the flexible display device to be peeled and the carrier substrate when destroying the bonding force between the flexible display device to be peeled and the carrier substrate, thereby forming a peeling area that is in contact but not bonded or partially not bonded in the functional area and a non-peeling area that is in contact and bonded in the non-functional area. Then, by cutting the carrier substrate, removing the carrier substrate in the peeling area, and then cutting the flexible display device to be peeled, the functional area is separated from the non-functional area, and finally removing the non-functional area of ​​the flexible display device to be peeled, a flexible display device with a retained functional area can be obtained. Due to the existence of the non-peeling area, the flexible display device to be peeled and the carrier substrate will not be relatively displaced, the flexible display device to be peeled will not fall off during transportation, and the carrier substrate will not slip, the transportation reliability is good, and the process yield of large-size flexible display devices is effectively improved. It can be understood that when preparing the flexible display device to be peeled on the carrier substrate, the range of each functional layer can be adjusted to adjust the functional area and non-functional area of ​​the flexible display device to be peeled, and then the peeling area and non-peeling area are determined.

[0049] In a specific example, the bonding force is destroyed by shielding the non-functional area of ​​the flexible display device to be peeled off and performing laser scanning on the functional area. It is understood that the laser scanning range can also be adjusted to scan only the functional area of ​​the flexible display device to be peeled off, thereby forming the above-mentioned peeling area and non-peeling area.

[0050] Optionally, the substrate of the flexible display device is polyimide (PI). In a specific example, the substrate of the flexible display device is colored polyimide, and the laser energy of the laser scanning is 120 mj / cm 2 ~160mj / cm 2, preferably 145mj / cm 2 In a specific example, the substrate of the flexible display device is transparent polyimide, and the laser energy of the laser scanning is 180mj / cm 2 ~220mj / cm 2 .

[0051] In a specific example, the non-functional area of ​​the flexible display device to be peeled is located at both ends, and the functional area is located between the non-functional areas. In the process of laser scanning, the opposite ends of the flexible display device to be peeled are shielded, so that the two ends form non-peeling areas, and the middle part forms a peeling area. It can be understood that the shielding range is determined according to the position of the non-functional area, and the distribution method is not limited thereto, and can be adjusted as needed. For example, when the non-functional area is located at one end of the flexible display device to be peeled, only one end can be shielded, or when the non-functional area is located at the edge of the flexible display device to be peeled and is in a ring shape, a ring shielding is performed.

[0052] In a specific example, a matte metal mask is used to shield the flexible display device to be peeled off in the non-functional area. It can be understood that the number and shape of the matte metal mask can be adjusted according to the shape of the non-functional area.

[0053] In a specific example, after the step of cutting the carrier substrate and before the step of removing the carrier substrate in the peeling area, the following step is further included: pressing down the carrier substrate in the bent non-peeling area. In this way, the carrier substrate in the peeling area can be removed more conveniently. Optionally, when pressing down the carrier substrate in the bent non-peeling area, the angle between the plane where the carrier substrate in the bent non-peeling area is located and the plane where the carrier substrate in the peeling area is located is 3° to 5°.

[0054] In a specific example, the step of cutting the carrier substrate is to place the flexible display device to be peeled and the carrier substrate on a separation platform, and the flexible display device to be peeled is located between the carrier substrate and the separation platform; wherein, during the process of cutting the carrier substrate, the separation platform vacuum absorbs the flexible display device to be peeled in the functional area; after the carrier substrate is cut, the carrier substrate in the non-peeling area is pressed down by a pressure roller, and the separation platform vacuum absorbs the flexible display device to be peeled in the non-functional area. In this way, the flexible display device to be peeled and the carrier substrate can be kept stable during the cutting process, and it is also easier to remove the carrier substrate in the peeling area after cutting.

[0055] In a specific example, removing the carrier substrate in the peeling area includes the following steps: sucking the carrier substrate and then vertically rising it while rotating it to move away from the flexible display device, i.e. slowly lifting one end edge by 2° to 3°, waiting for 1s to 2s, then lifting it by 3° to 5°, waiting for 1s to 2s, and then vertically rising it at a speed of 3mm / s to 5mm / s until the carrier substrate in the peeling area is completely separated from the flexible display device.

[0056] In a specific example, a carbon dioxide laser is used to cut the flexible display device to be peeled off, and then the flexible display device to be peeled off in the non-functional area is removed.

[0057] In a specific example, preparing a flexible display device to be peeled off on a carrier substrate includes the following steps: coating a flexible substrate solution on the carrier substrate, then performing high vacuum drying and high temperature heating to form a flexible substrate with uniform thickness, making a water and oxygen barrier layer and a TFT array (such as Oxide-TFT, LTPS TFT) on the flexible substrate, and then preparing a device functional layer and performing thin film packaging to complete the preparation of the flexible display device to be peeled off, and then performing film materials such as polarizers and color filters and bonding of driver ICs and PCBs.

[0058] like Figure 6 As shown, a stripping device according to an embodiment of the present invention is used to strip a flexible display device to be stripped on a carrier substrate. The flexible display device to be stripped has a functional area and a non-functional area. The stripping device includes a laser stripping mechanism (not shown), a separation platform 20, and a cutting mechanism (not shown). The laser stripping mechanism is used to perform laser scanning to destroy the bonding force between the flexible display device to be stripped in the functional area and the carrier substrate 300, so as to form a stripping area in contact but not bonded or partially non-bonded in the functional area and a non-stripping area in contact and bonded in the non-functional area. The cutting mechanism is used to cut the carrier substrate 300 and the flexible display device. The separation platform 20 includes a main body 21 and an inclined portion 22 connected to the main body 21. The main body 21 is used to carry the flexible display device to be stripped and the carrier substrate 300 corresponding to the stripping area. The inclined portion 22 is used to carry the flexible display device to be stripped and the carrier substrate 300 corresponding to the non-stripping area. The carrying surface of the inclined portion 22 is an inclined surface inclined to the side away from the carrying surface of the main body 21. After the carrier substrate 300 is cut, the carrier substrate 300 in the non-peeling area can be easily pressed down and bent by the bevel portion 22 , and then the carrier substrate 300 in the peeling area is separated from the flexible display device to be peeled off.

[0059] It is understood that the number of the inclined surface 22 can be one or more, and the specific shape can be adjusted according to the shape of the non-peeling area. Figure 6In the illustrated embodiment, there are two inclined surface portions 22, which are respectively connected to opposite ends of the main body portion 21. Preferably, the inclined surface angle of the inclined surface portion 22 is 3° to 5°.

[0060] In a specific example, the main body 21 and the bevel portion 22 are both provided with a plurality of vacuum adsorption holes 23 at intervals, and the distribution density of the vacuum adsorption holes 23 of the bevel portion 22 is greater than the distribution density of the vacuum adsorption holes 23 of the main body 21. In this way, during the process of cutting the carrier substrate 300, the separation platform 20 can vacuum adsorb the flexible display device corresponding to the peeling area 201 and the non-peeling area 202, so that the flexible display device and the carrier substrate 300 can be kept stable during the cutting process; after the carrier substrate 300 is cut, the separation platform 20 only vacuum adsorbs the flexible display device corresponding to the non-peeling area 202, so that the carrier substrate 300 corresponding to the peeling area 201 can be conveniently removed after cutting. At the same time, the vacuum adsorption holes 23 of the main body 21 are slightly sparsely distributed, and the vacuum degree is adjusted to a relatively strong state, which is suitable for adsorbing the carrier substrate 300, while the vacuum adsorption holes 23 of the bevel portion 22 are denser, and the vacuum degree is adjusted to a relatively weak state, which is suitable for adsorbing the flexible display device.

[0061] Optionally, the vacuum adsorption holes 23 of the main body 21 are distributed in an equidistant rectangular shape, with a hole diameter of 0.4 to 0.6 mm and a spacing of 8 mm to 12 mm; the vacuum adsorption holes 23 of the inclined portion 22 are distributed in rows with non-equidistant spacing, and the spacing between adjacent vacuum adsorption holes 23 gradually decreases in the direction away from the main body 21, and the distribution density gradually increases, for example, the spacing is 7 mm to 9 mm, 4 mm to 6 mm, and 1 mm to 3 mm, respectively.

[0062] Optionally, the laser lift-off mechanism includes one or more of a 308 nm excimer laser and a 405 nm semiconductor laser, preferably a 308 nm excimer laser.

[0063] In a specific example, if Figure 5 As shown, the stripping device further includes a shielding mechanism 10 , which is used to shield a portion of the flexible display device to be stripped and the carrier substrate 300 during laser scanning to form a stripping area 201 and a non-stripping area 202 .

[0064] In a specific example, if Figure 4As shown, the stripping device also includes a manipulator mechanism 30, which includes a frame 31 and a plurality of adsorbents 32 disposed on the frame 31, and the heights of the plurality of adsorbents 32 are independently adjustable, so that the flexible display device and / or the carrier substrate 300 can be driven to move more flexibly and conveniently, and the handling is more stable and efficient. Optionally, the areas at the opposite ends of the manipulator mechanism 30 are PCB adsorption areas 33, in which the adsorbents 32 are used to adsorb the PCB, and between the PCB adsorption areas 33 is a substrate adsorption area 34, in which the adsorbents 32 are used to adsorb the carrier substrate 300.

[0065] Alternatively, if Figure 7 As shown, the stripping device further includes a pressing roller 40 for pressing down the carrier substrate 300 in the bent non-stripping area 202 after cutting the carrier substrate 300 , thereby making it easier to remove the carrier substrate 300 in the stripping area 201 .

[0066] Example 1

[0067] This embodiment takes a flexible AMOLED display device as an example, and adopts a process scheme of first IC bonding and then laser peeling.

[0068] Step 1: Flexible AMOLED device preparation

[0069] like Figure 3 As shown, the PI solution is coated on the entire carrier substrate 300 by a slit coating process, dried under high vacuum, and heated at high temperature to form a flexible substrate 211 with uniform thickness. A water-oxygen barrier layer 212 and a TFT array 213 (such as Oxide-TFT, LTPS TFT) are fabricated on the flexible substrate 211, and flexible substrate materials with different temperature resistance can be selected according to different TFT process temperatures.

[0070] Next, the device functional layer 214 is prepared by a printing process or an evaporation process, and a thin film package 215 is formed to complete the preparation of the AMOLED display device, and then the polarizer 216, color filter and other film materials are attached, and the driver circuit board (PCB) is bound.

[0071] Step 2: Flexible AMOLED device handling

[0072] The flexible display device and the carrier substrate 300 are placed on the receiving platform with the carrier substrate 300 facing upwards. Figure 4The robot mechanism 30 shown transfers the flexible display device and the carrier substrate 300 to the laser stripping mechanism. The height of the suction piece 32 of the robot mechanism 30 is adjusted to be the same, and the flexible display device and the driver circuit board are sucked. The height of the flexible display device and the driver circuit board are consistent, and there is no relative displacement during the handling process, so as to prevent the flexible chip-on-film (COF) from falling off at the binding point with the carrier substrate 300 and the driver circuit board, resulting in poor binding.

[0073] The robot mechanism 30 slowly descends, and the flexible display device is placed face down on the working platform of the laser peeling mechanism. Then the platform vacuum is turned on to firmly suck the flexible display device. The robot mechanism 30 vacuum is turned off and the device is exited.

[0074] Step 3: Laser Lifting

[0075] like Figure 5 As shown, in the laser stripping mechanism, the black matte metal mask of the shielding mechanism 10 is aligned with the flexible display device to shield the non-functional area of ​​the flexible display device, and the required laser focal plane and laser energy density are set. The laser cutting head (cutter) is set to the required width, and the high-energy laser line beam penetrates the carrier substrate 300 and focuses on the interface between the flexible substrate 211 and the carrier substrate 300 to scan the flexible display device. The PI material in the functional area of ​​the flexible display device absorbs the laser energy, the bond energy between the PI material and the carrier substrate 300 is destroyed, and the PI material itself is decomposed and carbonized, accompanied by the release of a small amount of gas, so that the flexible substrate 211 is completely separated from the carrier substrate 300. The laser in the non-functional area is blocked by the black matte metal mask and cannot penetrate into the flexible substrate 211. The flexible substrate 211 that does not absorb the laser energy is still firmly bonded to the carrier substrate 300, thereby forming a stripping area 201 and a non-stripping area 202.

[0076] Different lasers are selected according to the absorption degree of PI materials to lasers of different wavelengths, such as 308nm excimer laser and 405nm semiconductor laser. In addition, the laser energy required for colored PI peeling is about 120mj / cm 2 ~160mj / cm 2 The laser energy required for colorless and transparent PI peeling is about 180mj / cm 2 ~220mj / cm 2 .

[0077] Step 4: Carrier Substrate Cutting

[0078] After the laser lift-off process is completed, the robot mechanism 30 descends, the suction member 32 turns on the vacuum, firmly sucks the carrier substrate 300 and the driving circuit board, and the robot mechanism 30 is lifted to transfer the flexible display device and the carrier substrate 300 to the separation platform 20. Figure 6 As shown, the main body 21 and the bevel portion 22 of the separation platform 20 correspond to the stripping area 201 and the non-stripping area 202 respectively. The bevel portion 22 is made of wedge-shaped stainless steel with a bevel angle of 3° to 5°. The bevel portion 22 is covered with vacuum adsorption holes 23. The main body 21 and the bevel portion 22 can independently control the vacuum degree. The vacuum adsorption holes of the main body 21 are slightly sparse, the vacuum degree is strong, and it is suitable for adsorbing the carrier substrate 300; the vacuum adsorption holes of the bevel portion 22 are denser, the vacuum degree is weak, and the gas flow rate is large, which is suitable for adsorbing flexible display devices.

[0079] like Figure 7 As shown, after CCD alignment, the carrier substrate 300 is cut along the edge of the non-peeling area by using a cutting mechanism such as a diamond cutter wheel, and then the carrier substrate 300 is split by pressing down with a pressure roller 40, so that the carrier substrate 300 and the flexible substrate 211 in the non-peeling area fall on the bevel portion 22 and are vacuum-absorbed by the bevel portion 22. The vacuum of the main body 21 is turned off, and air penetrates from the bevel portion 22 to the peeling area of ​​the flexible display device. After 5s to 10s, the flexible display device in the peeling area is completely separated from the carrier substrate 300 without any adhesive force.

[0080] Step 5: Separation of the flexible display device from the carrier substrate

[0081] like Figure 8 As shown, the robot mechanism 30 descends again, sucks the carrier substrate 300 in the stripping area 201, and adjusts the relative height of the suction piece 32, so that the suction pieces 32 at both ends of the robot mechanism 30 are tilted up in turn, slowly lifts the edge of the carrier substrate 300 in the stripping area by 2°~3°, waits for 1s~2s, then lifts it by 3°~5°, waits for 1s~2s, and then the robot mechanism 30 is vertically lifted at a speed of 3mm / s~5mm / s until the carrier substrate 300 in the stripping area is completely separated from the flexible display device. At this time, the flexible substrate 211 in the non-stripping area is still sucked by the vacuum, and the stripping area is irradiated with a high-energy laser. The flexible display device and the carrier substrate 300 have no adhesive force, and the carrier substrate 300 can be easily separated and lifted completely. Finally, after CCD alignment, the flexible substrate 211 in the non-stripping area is cut and removed using a cutting mechanism such as a carbon dioxide laser, and the back support film is attached to complete the entire process.

[0082] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a flexible display device, characterized in that: The following steps are involved: Preparing a to-be-peeled flexible display device on a carrier substrate, wherein the to-be-peeled flexible display device has a functional area and a non-functional area; Destroying the adhesive force between the to-be-peeled flexible display device in the functional area and the carrier substrate to form a peeling area in contact but not bonded or partially not bonded in the functional area and a non-peeling area in contact and bonded in the non-functional area; Cutting the carrier substrate to separate the carrier substrate in the stripping area from the carrier substrate in the non-stripping area, and removing the carrier substrate in the stripping area; and Cutting the to-be-peeled flexible display device to separate the functional area from the non-functional area, and removing the non-functional area; After the step of cutting the carrier substrate and before the step of removing the carrier substrate in the peeling area, the method further includes the following steps: Pressing down and bending the carrier substrate in the non-peeling area; The step of cutting the carrier substrate is performed by placing the flexible display device to be peeled off and the carrier substrate on a separation platform, and making the flexible display device to be peeled off be located between the carrier substrate and the separation platform; Wherein, during the process of cutting the carrier substrate, the separation platform vacuum absorbs the flexible display device to be peeled off from the functional area; After the carrier substrate is cut, a pressure roller is used to press down and bend the carrier substrate in the non-peeling area, and the separation platform vacuum absorbs the flexible display device to be peeled off in the non-functional area.

2. The preparation method according to claim 1, characterized in that: The method of destroying the adhesive force is to cover the flexible display device to be peeled off in the non-functional area and perform laser scanning on the functional area.

3. The preparation method according to claim 2, characterized in that: A matte metal mask is used to shield the flexible display device to be peeled off in the non-functional area.

4. The preparation method according to claim 1, characterized in that: When the carrier substrate in the non-peeling area is pressed down and bent, the angle between the plane where the carrier substrate in the bent non-peeling area is located and the plane where the carrier substrate in the peeling area is located is 3° to 5°.

5. A stripping device for implementing the preparation method according to claim 1, characterized in that: Used for peeling off a flexible display device to be peeled off on a carrier substrate, wherein the flexible display device to be peeled off has a functional area and a non-functional area, and the peeling device comprises: A laser peeling mechanism, wherein the laser peeling mechanism is used to perform laser scanning to destroy the adhesion between the flexible display device to be peeled off in the functional area and the carrier substrate, so as to form a peeling area that is in contact but not bonded or partially not bonded in the functional area and a non-peeling area that is in contact and bonded in the non-functional area; A cutting mechanism, wherein the cutting mechanism is used to cut the carrier substrate and the flexible display device to be peeled off; A separation platform, the separation platform comprising a main body and an inclined surface connected to the main body, the main body being used to carry the flexible display device to be peeled and the carrier substrate corresponding to the peeling area, the inclined surface being used to carry the flexible display device to be peeled and the carrier substrate corresponding to the non-peeling area, and the carrying surface of the inclined surface being an inclined surface inclined toward a side away from the carrying surface of the main body; A pressure roller is used to press down and bend the carrier substrate in the non-peeling area.

6. The stripping device according to claim 5, characterized in that Also includes: A shielding mechanism is used to shield the flexible display device to be peeled off and a partial area of ​​the carrier substrate during laser scanning to form the peeling area and the non-peeling area.

7. The stripping device according to claim 5, characterized in that The main body and the inclined surface are both provided with a plurality of vacuum adsorption holes at intervals, and the distribution density of the vacuum adsorption holes in the inclined surface is greater than the distribution density of the vacuum adsorption holes in the main body.

8. The stripping device according to claim 7, characterized in that The vacuum adsorption holes of the main body are distributed at equal intervals, the diameter of the vacuum adsorption holes of the main body is 0.4-0.6 mm, and the distance between adjacent vacuum adsorption holes is 8 mm-12 mm; and / or The vacuum adsorption holes of the inclined portion are distributed in rows with non-equidistant intervals, and the intervals between adjacent vacuum adsorption holes gradually decrease in a direction away from the main body portion.

9. The stripping device according to any one of claims 5 to 7, characterized in that: Also includes: A manipulator mechanism comprises a frame and a plurality of adsorption members arranged on the frame, and the heights of the plurality of adsorption members are independently adjustable.

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