| (11) | EP 3 561 799 A1 |
(12) | EUROPEAN PATENT APPLICATION |
published in accordance with Art. 153(4) EPC |
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(54) | METHOD FOR MANUFACTURING FLEXIBLE ARRAY SUBSTRATE |
(57) Disclosed is a method for manufacturing a flexible array substrate. The method comprises: first attaching a flexible substrate (3) to a rigid support plate (1) to manufacture a back drive circuit (4) and manufacturing, on the back drive circuit (4), a protective layer (5); then, after tearing off and turning over the flexible substrate (3), re-attaching same to the rigid support plate (1), so that the protective layer (5) comes into contact with an adhesive layer (2); and then forming a via hole (6) in the flexible substrate (3) to manufacture a front drive circuit (7) and a display circuit, wherein the front drive circuit (7) is electrically connected to the display circuit, and the back drive circuit (4) is electrically connected to the display circuit by means of the via hole (6), thus manufacturing a flexible array substrate with circuit structures on two sides. By means of distributing circuit structures in a non-display region to two sides of the flexible substrate (3), the width of the non-display region can be reduced, thereby realising ultra-narrow border or borderless display. |
BACKGROUND OF THE INVENTION
1. Field of the Invention
2. The Related Arts
SUMMARY OF THE INVENTION
Step 1: providing a rigid support plate and a flexible substrate, adhering the flexible substrate to the rigid support plate with an adhesive layer so that the back side of the flexible substrate facing away from the rigid support plate;
Step 2: forming a back side driver circuit on the back side of the flexible substrate and covering a protective layer on the back side driver circuit;
Step 3: separating the flexible substrate from the rigid support plate, turning the flexible substrate over and adhering the flexible substrate to the rigid support plate with the adhesive layer so that the front side of the flexible substrate facing away from the rigid support plate, with the protective layer contacting the adhesive layer;
Step 4: forming holes penetrating the flexible substrate in a predefined non-active area on the front side of the flexible substrate, exposing the back side driver circuit on the back side of the flexible substrate;
Step 5: forming a front side driver circuit and a display circuit respectively on the predefined non-active area and active area on the front side of the flexible substrate, the front side driver circuit being electrically connected to the display circuit, and the back side driver circuit being electrically connected to the display circuit through the holes;
Step 6: separating the flexible substrate from the rigid support plate to obtain the flexile array substrate.
Step 1: providing a rigid support plate and a flexible substrate, adhering the flexible substrate to the rigid support plate with an adhesive layer so that the back side of the flexible substrate facing away from the rigid support plate;
Step 2: forming a back side driver circuit on the back side of the flexible substrate and covering a protective layer on the back side driver circuit;
Step 3: separating the flexible substrate from the rigid support plate, turning the flexible substrate over and adhering the flexible substrate to the rigid support plate with the adhesive layer so that the front side of the flexible substrate facing away from the rigid support plate, with the protective layer contacting the adhesive layer;
Step 4: forming holes penetrating the flexible substrate in a predefined non-active area on the front side of the flexible substrate, exposing the back side driver circuit on the back side of the flexible substrate;
Step 5: forming a front side driver circuit and a display circuit respectively on the predefined non-active area and active area on the front side of the flexible substrate, the front side driver circuit being electrically connected to the display circuit, and the back side driver circuit being electrically connected to the display circuit through the holes;
Step 6: separating the flexible substrate from the rigid support plate to obtain the flexile array substrate;
wherein the rigid support plate being made of glass;BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic view showing a structure of known liquid crystal display (LCD) device;
Figure 2 is a schematic view showing Step 1 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 3 is a schematic view showing Step 2 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 4 and Figure 5 are schematic views showing Step 3 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 6 is a schematic view showing Step 4 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 7 is a schematic view showing Step 5 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 8 is a schematic view showing Step 6 of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention;
Figure 9 is a schematic view showing the flowchart of the manufacturing method of flexible array substrate provided by the first embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Step 1: referring to Figure 2, providing a rigid support plate 1 and a flexible substrate 3, adhering the flexible substrate 3 to the rigid support plate 1 with an adhesive layer 2 so that the back side of the flexible substrate 3 facing away from the rigid support plate 1.
Specifically, the rigid support plate 1 is made of glass; the material of the flexible substrate 3 is polyimide (PI), polyethylene terephthalate (PET), cycloolefin copolymer (COC), or polyether resin (PES); the thickness of the flexible substrate is 10-300µm, which facilitates the subsequent drilling of holes. The adhesive layer 2 can be made of pressure-sensitive glue or temperature-controlled glue.
Step 2: referring to Figure 3, forming a back side driver circuit 4 on the back side of the flexible substrate 3 and covering a protective layer 5 on the back side driver circuit 4.
Specifically, the protective layer 5 is made with an inorganic oxide deposition process or an organic material coating process.
Step 3: referring to Figure 4, separating the flexible substrate 3 from the rigid support plate 1, turning the flexible substrate 3 over and adhering the flexible substrate 3 to the rigid support plate 1 with the adhesive layer 2 so that the front side of the flexible substrate 3 facing away from the rigid support plate 1, with the protective layer 5 contacting the adhesive layer 2.
Specifically, in Step 3, the flexible substrate 3 is separated from the rigid support plate 1 by a laser peeling process. Alternatively, the adhesive layer 2 is made of a temperature-controlled glue, and separating the flexible substrate 3 from the rigid support plate 1 is by changing the temperature of the adhesive layer 2.
Step 4: referring to Figure 6, forming holes 6 penetrating the flexible substrate 3 in a predefined non-active area on the front side of the flexible substrate 3, exposing the back side driver circuit 4 on the back side of the flexible substrate 3.
Specifically, in Step 4, the holes 6 are formed by a laser drilling process or a chemistry etching process. The diameter of the holes must match the diameter of the wires to be passing through the holes 6; and preferably, the diameter of the hole is 5-100µm.
Step 5: referring to Figure 7, forming a front side driver circuit 7 and a display circuit respectively on the predefined non-active area and active area on the front side of the flexible substrate 3, the front side driver circuit 7 being electrically connected to the display circuit, and the back side driver circuit 4 being electrically connected to the display circuit through the holes 6.
Specifically, because the thickness of the flexible substrate 3 is much reduced than the thickness of the known glass substrate, the yield rate of Step 4 of forming holes 6 and Step 5 of forming wires to connect the back side driver circuit 4 to the display circuit in the holes 6 can be ensured so that the process can proceed.
Specifically, the active area is located at the center of the flexible substrate 3, and the non-active area surrounding the active area. The front side driver circuit 7 and the back side driver circuit 4 together form the wire on array (WOA) of the flexible array substrate. The display circuit comprises a plurality of data lines and a plurality of scan lines; the data lines and the scan lines intersect perpendicularly to form a plurality of pixel units. Each wire of the WOA corresponds to a data line or a scan line. Each wire receives a scan signal or data signal externally and transports to the corresponding scan line or data line to achieve displaying.
It should be noted that the present invention is also applicable to array substrate using GOA technology. At this point, the front side driver circuit 7 and the back side driver circuit 4 together form the wire on array (WOA) and the gate driver on array (GOA) circuit of the flexible array substrate. The GOA circuit comprises a plurality of GOA units, with each corresponding to a scan line. Each wire of WOA is electrically connected to a data line or a GOA unit. Each wire passes the received external signal to the GOA unit to generate a scan signal, which is passed to the scan line, or receives a data line and passes to a data line to achieve displaying. The GOA technology eliminates the need for external gate driver chip to further reduce the border width of the display.
It should be noted that by distributing the circuit structure in the non-active area (comprising WOA and GOA) to both sides of the flexible substrate can greatly reduce the area in the non-active area occupied by the circuit structure compared to placing only on one side of the flexible substrate. As such, the width of the non-active area is reduced to achieve ultra-narrow border or borderless display.
Step 6: separating the flexible substrate 3 from the rigid support plate 1 to obtain the flexile array substrate.
Step 1: providing a rigid support plate and a flexible substrate, adhering the flexible substrate to the rigid support plate with an adhesive layer so that the back side of the flexible substrate facing away from the rigid support plate;
Step 2: forming a back side driver circuit on the back side of the flexible substrate and covering a protective layer on the back side driver circuit;
Step 3: separating the flexible substrate from the rigid support plate, turning the flexible substrate over and adhering the flexible substrate to the rigid support plate with the adhesive layer so that the front side of the flexible substrate facing away from the rigid support plate, with the protective layer contacting the adhesive layer;
Step 4: forming holes penetrating the flexible substrate in a predefined non-active area on the front side of the flexible substrate, exposing the back side driver circuit on the back side of the flexible substrate;
Step 5: forming a front side driver circuit and a display circuit respectively on the predefined non-active area and active area on the front side of the flexible substrate, the front side driver circuit being electrically connected to the display circuit, and the back side driver circuit being electrically connected to the display circuit through the holes;
Step 6: separating the flexible substrate from the rigid support plate to obtain the flexile array substrate.
Step 1: providing a rigid support plate and a flexible substrate, adhering the flexible substrate to the rigid support plate with an adhesive layer so that the back side of the flexible substrate facing away from the rigid support plate;
Step 2: forming a back side driver circuit on the back side of the flexible substrate and covering a protective layer on the back side driver circuit;
Step 3: separating the flexible substrate from the rigid support plate, turning the flexible substrate over and adhering the flexible substrate to the rigid support plate with the adhesive layer so that the front side of the flexible substrate facing away from the rigid support plate, with the protective layer contacting the adhesive layer;
Step 4: forming holes penetrating the flexible substrate in a predefined non-active area on the front side of the flexible substrate, exposing the back side driver circuit on the back side of the flexible substrate;
Step 5: forming a front side driver circuit and a display circuit respectively on the predefined non-active area and active area on the front side of the flexible substrate, the front side driver circuit being electrically connected to the display circuit, and the back side driver circuit being electrically connected to the display circuit through the holes;
Step 6: separating the flexible substrate from the rigid support plate to obtain the flexile array substrate;
wherein the rigid support plat is made of glass;