Method for manufacturing flexible array substrate

Abstract

The present invention provides a method for manufacturing a flexible array substrate. The method includes, first, successively forming an adhesive layer, a passivation layer, a back-side drive circuit, a planarization layer, a flexible backing plate, and a front-side drive circuit and a display circuit, in a stacked arrangement, on a rigid support plate and then peeling off the rigid support plate and the adhesive layer to form a flexible array substrate having a double-sided circuit structure. The entire process requires no steps of peeling, reversing, and then re-attaching of the flexible backing plate so that it is possible to avoid the issues of poor flatness and low yield resulting from improper or wrongful re-attachment of the flexible backing plate and thus, fabrication difficulty of a flexible array substrate having a double-sided circuit structure may be lowered down to thereby improve fabrication yield of the flexible array substrate.

Claims

1. A method for manufacturing a flexible array substrate, comprising the following steps: Step S1: providing a rigid support plate, forming an adhesive layer on the rigid support plate, and forming a passivation layer on the adhesive layer; Step S2: forming a back-side drive circuit on the passivation layer and covering the back-side drive circuit with a planarization layer; Step S3: forming a flexible backing plate on the planarization layer; Step S4: forming a conductive via in the flexible backing plate to extend through the flexible backing plate and the planarization layer; Step S5: forming a front-side drive circuit and a display circuit on the flexible backing plate, the display circuit being in electrical connection with the front-side drive circuit, such that the front-side drive circuit is electrically connected, through the via, to the back-side drive circuit; and Step S6: peeling off the rigid support plate and the adhesive layer to obtain the flexible array substrate.

2. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the rigid support plate is made of glass.

3. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the flexible backing plate is made of a material comprising polyimide, polyethylene terephthalate, cyclic olefin copolymer, or polyethersulfone resin.

4. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the flexible backing plate has a thickness of 5-500 micrometers.

5. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein Step S4 uses an operation of laser drilling or chemical corrosion to form the via.

6. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the via has a diameter of 5-100 micrometers.

7. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein Step S6 uses an operation of laser peeling to peel off the rigid support plate and the adhesive layer.

8. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein Step S3 uses an operation of coating or attachment to form the flexible backing plate on the planarization layer.

9. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the front-side drive circuit and the back-side drive circuit collectively form wire-on-array (WOA) lines on the flexible array substrate.

10. The method for manufacturing a flexible array substrate as claimed in claim 1, wherein the front-side drive circuit and the back-side drive circuit collectively form wire-on-array (WOA) lines and a gate-driver-on-array (GOA) circuit of the flexible array substrate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For better understanding of the features and technical contents of the present invention, reference will be made to the following detailed description of the present invention and the attached drawings. However, the drawings are provided only for reference and illustration and are not intended to limit the present invention.

(2) In the drawings:

(3) FIG. 1 is a schematic view illustrating a structure of a known liquid crystal display;

(4) FIG. 2 is a schematic view illustrating Step S1 of a method for manufacturing a flexible array substrate according to the present invention;

(5) FIG. 3 is a schematic view illustrating Step S2 of the method for manufacturing a flexible array substrate according to the present invention;

(6) FIG. 4 is a schematic view illustrating Step S3 of the method for manufacturing a flexible array substrate according to the present invention;

(7) FIG. 5 is a schematic view illustrating Step S4 of the method for manufacturing a flexible array substrate according to the present invention;

(8) FIG. 6 is a schematic view illustrating Step S5 of the method for manufacturing a flexible array substrate according to the present invention;

(9) FIG. 7 is a schematic view illustrating Step S6 of the method for manufacturing a flexible array substrate according to the present invention; and

(10) FIG. 8 is a flow chart illustrating the method for manufacturing a flexible array substrate according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(11) To further expound the technical solution adopted in the present invention and the advantages thereof, a detailed description will be given with reference to the preferred embodiments of the present invention and the drawings thereof.

(12) Referring to FIG. 8, the present invention provides a method for manufacturing a flexible array substrate, which comprises the following steps:

(13) Step S1: referring to FIG. 2, providing a rigid support plate 1, forming an adhesive layer 2 on the rigid support plate 1, and forming a passivation layer 3 on the adhesive layer 2.

(14) Specifically, the rigid support plate 1 is made of a material of glass. The adhesive layer 2 is made of an adhesive material that is selected as pressure-sensitive adhesive or temperature controllable adhesive. The passivation layer 3 is made of a material comprising an inorganic material, such as silicon oxide (SiOx) and silicon nitride (SiNx) formed through physical vapor deposition (PVD), or alternatively comprising an organic material, such as polyfluoroalkoxy (PFA) formed through chemical vapor deposition (CVD). The passivation layer 3 is provided for protection of a back-side drive circuit 4 that is formed subsequently.

(15) Step S2: referring to FIG. 3, forming a back-side drive circuit 4 on the passivation layer 3 and covering the back-side drive circuit 4 with a planarization layer 5.

(16) Step S3: referring to FIG. 4, forming a flexible backing plate 6 on the planarization layer 5.

(17) Specifically, the flexible backing plate 6 is made of a material comprising polyimide (PI), polyethylene terephthalate (PET), cyclic olefin copolymer (COC), or polyethersulfone resin (PES) and the flexible backing plate 6 is formed through coating or attachment in order to facilitate subsequent performance of a perforation operation. The flexible backing plate 6 has a thickness that should not be excessively large and preferably, the thickness of the flexible backing plate 6 is in the range of 5-500 micrometers.

(18) Step S4: referring to FIG. 5, forming a via 7 in the flexible backing plate 6 to extend through the flexible backing plate 6 and the planarization layer 5.

(19) Specifically, Step S4 may involve an operation of laser drilling or chemical corrosion to form the via 7. The via 7 has a diameter that is selected to match a diameter of a conductor to be received through the via 7, and preferably, the diameter of the via 7 is 5-100 micrometers.

(20) Step S5: referring to FIG. 6, forming a front-side drive circuit 8 and a display circuit 9 that is in electrical connection with the front-side drive circuit 8 on the flexible backing plate 6, such that the front-side drive circuit 8 is electrically connected, through the via 7, to the back-side drive circuit 4.

(21) Specifically, the front-side drive circuit 8 is formed on the flexible backing plate 6 in a predetermined area of a non-display zone, and the display circuit 9 is formed on the flexible backing plate 6 in a predetermined area of a display zone, wherein the display zone is located at a central area of the flexible backing plate 6 and the non-display zone surrounds the display zone.

(22) Optionally, the flexible array substrate may adopt a configuration of externally connecting drive chips. The front-side drive circuit 8 and the back-side drive circuit 4 collectively form wire-on-array (WOA) lines of the flexible array substrate and the display circuit 9 comprises a plurality of data lines and a plurality of scan lines, wherein the plurality of data lines and the plurality of scan lines perpendicularly intersect to form a plurality of pixel units. Each of the WOA lines is corresponding to and electrically connected to one of the data lines or one of the scan lines, and each of the WOA lines receives a scan signal or a data signal from an external source for subsequent transmission to the corresponding one of the scan lines or the data lines for achieving image displaying.

(23) Optionally, the flexible array substrate may adopt a gate-driver-on-array (GOA) configuration. The front-side drive circuit 8 and the back-side drive circuit 4 collectively form the WOA lines and a GOA circuit of the flexible array substrate, wherein the GOA circuit comprises a plurality of GOA units respectively corresponding to the scan lines. Each of the WOA lines is corresponding to and electrically connected to one of the data lines or one of the GOA units. Each of the WOA lines receives a signal from an external source and subsequently transmits the signal to the GOA units to generate a scan signal that is subsequently transmitted to the scan lines or receives a data signal that is transmitted to the data lines, so as to achieve image displaying. Adoption of the GOA technique make it possible to omit connection with external driver chips so as to further reduce a width of a bezel of a display device.

(24) Step S6: referring to FIG. 7, peeling off the rigid support plate 1 and the adhesive layer 2 to obtain a flexible array substrate.

(25) Specifically, Step S6 involves an operation of laser peeling to peel off the rigid support plate 1 and the adhesive layer 2.

(26) Further, with the above technique, the circuit structure (which may comprise a WOA circuit and a GOA circuit) of a non-display zone is distributed to two surfaces of the flexible backing plate, so that compared to an arrangement where the circuit structure of the non-display zone is completely set on the same surface of the flexible backing plate, a laying area occupied by the circuit structure of the non-display zone can be greatly reduced and thus, the width occupied by the non-display zone can be reduced to help achieve ultra-slim bezel or bezel-free displaying.

(27) Importantly, in the above-described method, a flexible array substrate having a double-sized circuit structure is formed by first forming a back-side drive circuit 4, then forming a flexible backing plate 6 on the back-side drive circuit 4, and finally forming a front-side drive circuit 8 and a display circuit 9 on the flexible backing plate 6 and, as compared to the prior art, the entire process requires no steps of peeling, reversing, and then re-attaching of the flexible backing plate 6 so that it is possible to avoid the issues of poor flatness and low yield resulting from improper or wrongful re-attachment of the flexible backing plate 6 and thus, fabrication difficulty of a flexible array substrate having a double-sided circuit structure may be lowered down to thereby improve fabrication yield of the flexible array substrate.

(28) In summary, the present invention provides a method for manufacturing a flexible array substrate. The method comprises, first, successively forming an adhesive layer, a passivation layer, a back-side drive circuit, a planarization layer, a flexible backing plate, and a front-side drive circuit and a display circuit, in a stacked arrangement, on a rigid support plate and then peeling off the rigid support plate and the adhesive layer to form a flexible array substrate having a double-sided circuit structure. The entire process requires no steps of peeling, reversing, and then re-attaching of the flexible backing plate so that it is possible to avoid the issues of poor flatness and low yield resulting from improper or wrongful re-attachment of the flexible backing plate and thus, fabrication difficulty of a flexible array substrate having a double-sided circuit structure may be lowered down to thereby improve fabrication yield of the flexible array substrate.

(29) Based on the description given above, those having ordinary skills in the art may easily contemplate various changes and modifications of he technical solution and the technical ideas of the present invention. All these changes and modifications are considered belonging to the protection scope of the present invention as defined in the appended claims.