Display device and method of manufacturing the same

Abstract

The present application relates to a display device and a method for manufacturing the display device. The display device includes a display panel. A flexible printed circuit board is electrically connected to the display panel. A first pad is disposed on the display panel. A second pad is disposed on the flexible printed circuit board and overlaps with the first pad. A first anisotropic conductive film is disposed between the first pad and the second pad. The first anisotropic conductive film is configured to bond the first pad to the second pad. The first anisotropic conductive film includes a conductive polymer. The first anisotropic conductive film includes at least one first insulating region and at least one first conductive region electrically connecting the first pad and the second pad.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority benefit of Korean Patent Application No. 10-2018-0160209 filed on December 12, 2018 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to a display device and a method for manufacturing the same. Background Art

[0004] Display devices such as organic light emitting diode displays and liquid crystal displays are used in a wide variety of electronic devices. The display device includes a display panel, which includes pixels for displaying an image. In addition to the pixels, a pad portion and a driver for inputting and outputting signals for controlling the pixels may also be provided in the display panel. The display panel may also include an integrated circuit (IC) chip or a chip-like flexible printed circuit board (FPCB) coupled to the pad portion.

[0005] Anisotropic conductive film (ACF) including conductive balls can be used to physically connect the FPCB to the electrical connection portion of the pad portion. As display devices have increased resolution and circuits are integrated, the distance between pads gradually narrows. Therefore, the electrical connection portion of the pad needs to have improved reliability.

[0006] In the bonding process of anisotropic conductive film including conductive balls, the conductive balls may not be uniformly captured in all areas of the pad portion by resin flow. When the conductive balls are excessively concentrated in some areas, the adjacent pads in the surface direction may be short-circuited. In addition, when the conductive balls are insufficient in some areas, the facing pads may not be electrically connected. In addition, the pitch and area of ​​the pads can be restricted to electrically connect the facing pads to each other by using conductive balls with a specific size and volume and irregular arrangement, and at the same time prevent the adjacent pads from being electrically connected. For example, when the distance between the pads is closer than a specific level, the adjacent pads may be short-circuited. When the pad area is insufficient, the facing pads may not be electrically connected to each other. This can be particularly problematic in high-resolution display devices where a large number of pads need to be integrated into a specific area. Summary of the invention

[0007] In an exemplary embodiment of the present invention, a display device includes a display panel. A flexible printed circuit board is electrically connected to the display panel. A first pad is disposed on the display panel. A second pad is disposed on the flexible printed circuit board and overlaps the first pad. A first anisotropic conductive film is disposed between the first pad and the second pad. The first anisotropic conductive film is configured to bond the first pad to the second pad. The first anisotropic conductive film includes a conductive polymer. The first anisotropic conductive film includes at least one first insulating region and at least one first conductive region electrically connecting the first pad and the second pad.

[0008] The first conductive region may be disposed in a region where the first pad and the second pad overlap, and the first insulating region may be disposed in a region surrounding the first conductive region.

[0009] The conductive polymer may include at least one of polyacetylene, polypyrrole, polythiophene, polyphenylene vinylene, and polyphenylene.

[0010] The first conductive region may include trans-polyacetylene, and the first insulating region may include cis-polyacetylene.

[0011] The first pads may have a small pitch, and the pitch of the first pads may be 27 μm or less.

[0012] The display device may further include a printed circuit board, a third pad disposed on the flexible printed circuit board, and a fourth pad disposed on the printed circuit board.

[0013] The display device may further include a second anisotropic conductive film disposed between the third pad and the fourth pad, the second anisotropic conductive film configured to couple the third pad to the fourth pad.

[0014] The second anisotropic conductive film may include a conductive polymer.

[0015] The second anisotropic conductive film may include a second insulating region and a second conductive region configured to electrically connect the third pad and the fourth pad, and the second conductive region may be disposed in a region where the third pad and the fourth pad overlap.

[0016] The flexible printed circuit board may include a data driver integrated circuit.

[0017] The data driver integrated circuit may transmit a signal to the display panel through the second pad, the first anisotropic conductive film, and the first pad.

[0018] In an exemplary embodiment of the present invention, a display device includes a display panel. A flexible printed circuit board is electrically connected to the display panel. A first pad is disposed on the display panel. A second pad is disposed on the flexible printed circuit board and overlaps the first pad. A first anisotropic conductive film is disposed between the first pad and the second pad. The first anisotropic conductive film is configured to couple the first pad to the second pad. The first anisotropic conductive film includes at least one first insulating region and at least one first conductive region configured to electrically connect the first pad to the second pad. The at least one first conductive region includes polycrystalline silicon. The at least one insulating region includes amorphous silicon.

[0019] The first conductive region may be disposed in a region where the first pad and the second pad overlap, and the first insulating region may be disposed in a region surrounding the first conductive region.

[0020] The first anisotropic conductive film may further include a thermosetting resin or a photocurable resin.

[0021] The display device may further include a printed circuit board, a third pad disposed on the flexible printed circuit board, a fourth pad disposed on the printed circuit board, and a second anisotropic conductive film disposed between the third pad and the fourth pad.

[0022] The second anisotropic conductive film may include a second insulating region and a second conductive region configured to electrically connect the third pad to the fourth pad, the second conductive region includes polysilicon, and the second insulating region may include amorphous silicon.

[0023] The second anisotropic conductive film may further include a thermosetting resin or a photocurable resin.

[0024] In an exemplary embodiment of the present invention, a method for manufacturing a display device includes providing a display panel and a flexible printed circuit board. An anisotropic conductive film is attached to the display panel or the flexible printed circuit board. A mask is provided on the anisotropic conductive film. The mask includes an opening in a region corresponding to a pad of the display panel or a pad of the flexible printed circuit board. A laser is irradiated onto a region of the anisotropic conductive film that overlaps with a pad of the display panel or a pad of the flexible printed circuit board through the opening of the mask to form at least one conductive region located in the irradiated region and at least one insulating region located in the non-irradiated region.

[0025] The exemplary embodiment includes a structure capable of making electrical connections between pads without including conductive balls. Therefore, there is no restriction on the pitch or area of ​​the pads depending on the density, size, etc. of the conductive balls, and since there is no problem of short circuit or open circuit caused by the conductive balls, the connection reliability of the pads can be improved. In addition, since the pads allow the formation of a small pitch and area, the dead space set around the area where the image is displayed in the display device can be reduced, and a high-resolution display device can be realized, thereby increasing the design freedom of the display device.

[0026] The anisotropic conductive film may include a conductive polymer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a block diagram schematically illustrating a display device according to an exemplary embodiment of the inventive concept.

[0028] Figure 2 A cross-sectional view of a display device according to an exemplary embodiment of the inventive concept is shown.

[0029] Figure 3 An exemplary embodiment according to the present inventive concept is shown. Figure 1 An exploded perspective view of an enlarged portion A of FIG.

[0030] Figure 4 An exploded perspective view of a display apparatus according to an exemplary embodiment of the inventive concept is illustrated.

[0031] Figure 5 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the inventive concept.

[0032] Figure 6 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment of the inventive concept. DETAILED DESCRIPTION

[0033] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the inventive concept are shown. As will be appreciated by those skilled in the art, the described exemplary embodiments may be modified in many different ways without departing from the spirit or scope of the inventive concept.

[0034] In order to clearly describe the inventive concept, parts irrelevant to the description are omitted, and the same reference numerals refer to the same or similar constituent elements throughout the specification.

[0035] In addition, since the sizes and thicknesses of the components shown in the drawings are arbitrarily given for better understanding and ease of description, the inventive concept is not limited to the sizes and thicknesses shown. For example, in the drawings, the thicknesses of layers, films, panels, regions, etc. may be exaggerated for clarity. In the drawings, the thicknesses of some layers and regions may be exaggerated for better understanding and ease of description.

[0036] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it may be directly on the other element, or there may also be intervening elements. Conversely, when an element is referred to as being "directly on" another element, there are no intervening elements. In addition, the words "above" or "on..." refer to being positioned above or below an object portion, and do not necessarily mean being positioned on the upper side of the object portion based on the direction of gravity.

[0037] In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0038] Furthermore, in the specification, the phrase “in a plan view” means when an object portion is viewed from above, and the phrase “in a cross-sectional view” means when a cross section taken by vertically cutting the object portion is viewed from the side.

[0039] In the following, reference will be made to Figures 1 to 3 A display device according to an exemplary embodiment of the inventive concept is described. Figure 1 A display device 10 according to an exemplary embodiment of the inventive concept is schematically illustrated.

[0040] refer to Figure 1 According to an exemplary embodiment of the inventive concept, the display device 10 may include a display panel 100, a flexible printed circuit board 200 connected to the display panel 100, and a printed circuit board (PCB) 300 connected to the flexible printed circuit board 200. In an exemplary embodiment, the display panel 100 may be an organic light emitting diode display panel, a liquid crystal panel, or other display panels known in the art.

[0041] The display panel 100 may include a display area DA for displaying an image and a non-display area NA in which elements and wirings for generating and transmitting various signals applied to the display area DA may be disposed. The non-display area NA may be disposed at an outer periphery of the display area DA. Figure 1The side edge region (e.g., the lower edge region) of the display panel 100 is shown as the non-display region NA, but other side edge regions (e.g., the left edge region, the right edge region, and / or the upper edge region) may correspond to the non-display region NA, and the non-display region NA may be disposed in a region surrounding the display region DA. Although the display region DA is shown as a quadrilateral, the display region DA may have various shapes such as a circle, an ellipse, and a polygon other than the quadrilateral.

[0042] The pixels PX may be arranged in a display area DA of the display panel 100. The pixels PX may be arranged in a matrix form. Signal lines such as gate lines and data lines may also be arranged in the display area DA. The gate lines may extend in a substantially row direction (e.g., a horizontal direction), and the data lines may extend in a substantially column direction (e.g., a vertical direction). Each pixel PX may be connected to the gate lines and the data lines to receive gate signals and data signals from these signal lines.

[0043] The first pad portion PP1 including the pad PE for receiving a signal from the outside of the display panel 100 may be disposed in the non-display area NA of the display panel 100. The plurality of signal lines 11 disposed in the display area DA may extend to the non-display area NA to be connected to the pad PE of the first pad portion PP1. In an exemplary embodiment, the gate driver may be integrated into the non-display area NA of the display panel 100 and may be provided in the form of an integrated circuit chip.

[0044] The flexible printed circuit board 200 may be bent, and a first end of the flexible printed circuit board 200 may be electrically connected to the signal line 11 of the display panel 100. The first end of the flexible printed circuit board 200 may overlap with the first pad portion PP1 of the display panel 100, and the flexible printed circuit board 200 and the display panel 100 may be electrically connected to each other in the first pad portion PP1. As will be described later, the display panel 100 may be connected to the flexible printed circuit board 200 through an anisotropic conductive film to receive a signal from the flexible printed circuit board 200.

[0045] The flexible printed circuit board 200 may include a data driver integrated circuit 400 for generating a data voltage as a grayscale voltage corresponding to an input video signal. The data driver integrated circuit 400 may be mounted on the flexible printed circuit board 200 and may be connected to the first pad portion PP1 in the form of a tape carrier package. However, in an alternative embodiment, the data driver integrated circuit 400 may be mounted on a different portion of the display device 10, such as on a non-display area NA of the display panel 100 between the display area DA and the first pad portion PP1 in the form of an integrated circuit chip.

[0046] A second pad portion PP2 including a pad PE for receiving a signal may be disposed on a second end of the flexible printed circuit board 200. A first end of the printed circuit board 300 may be connected to the second pad portion PP2 of the flexible printed circuit board 200. In an exemplary embodiment, the flexible printed circuit board 200 and the printed circuit board 300 may be electrically connected through an anisotropic conductive film.

[0047] The printed circuit board 300 may include a signal controller for controlling a gate driver of the display panel 100. The signal controller may be disposed on the printed circuit board 300 to transmit a signal to the display panel 100 through the flexible printed circuit board 200.

[0048] Figure 2 A cross-sectional view of a display device according to an exemplary embodiment of the inventive concept is shown. Figure 2 Specifically shown is a cross-sectional view of the display device 10 in which the flexible printed circuit board 200 is bent.

[0049] As described above, the display device 10 includes the display panel 100 , the flexible printed circuit board 200 , and the printed circuit board 300 .

[0050] The display panel 100 may include a substrate 110. The substrate 110 may include a flexible material such as plastic that may be bent, curved, folded, or rolled.

[0051] The thin film transistor display panel 120 and the first pad PE1a may be disposed on the substrate 110. Figure 3 In the exemplary embodiment shown in FIG. 1 , the first pad PE1a includes three rectangular pads spaced apart from each other. However, the number of pads and the shape of the pads are not limited thereto. The thin film transistor display panel 120 may be disposed Figure 1 The thin film transistor display panel 120 may include at least one thin film transistor and a plurality of signal lines, wherein the plurality of signal lines include a plurality of gate lines, a plurality of data lines and a plurality of driving voltage lines.

[0052] In an exemplary embodiment, the first pad PE1a may be disposed at an edge of the substrate 110 and may be disposed in the non-display area NA. A plurality of signal lines disposed in the thin film transistor display panel 120 may extend to the non-display area NA to be connected to the first pad PE1a.

[0053] The flexible printed circuit board 200 may include a data driver integrated circuit 400, a second pad PE1b, and a third pad PE2a. The flexible printed circuit board 200 may be bent toward the bottom of the substrate 110. In other words, the flexible printed circuit board 200 may be bent in a direction toward a surface of the substrate 110 opposite to a surface thereof on which the thin film transistor display panel 120 is disposed.

[0054] The data driver integrated circuit 400 may be disposed on the lower surface of the flexible printed circuit board 200 before bending, and may be disposed under the substrate 110 of the display panel 100 after bending the flexible printed circuit board 200. The data driver integrated circuit 400 may be electrically connected to the first and second pads PE1a and PE1b.

[0055] The second pad PE1b may be disposed on the first end of the flexible printed circuit board 200 and may be electrically connected to the first pad PE1a of the display panel 100 through the first anisotropic conductive film 510. The first anisotropic conductive film 510 may have a first surface in contact with the first pad PE1a and a second surface in contact with the second pad PE1b. The first anisotropic conductive film 510 may combine the first pad PE1a of the display panel 100 and the second pad PE1b of the flexible printed circuit board 200 and may electrically connect them at the same time.

[0056] The third pad PE2a is disposed on the second end of the flexible printed circuit board 200 and may be electrically connected to the fourth pad PE2b of the printed circuit board 300 through the second anisotropic conductive film 520. The second anisotropic conductive film 520 may have a first surface in contact with the third pad PE2a and a second surface in contact with the fourth pad PE2b. The second anisotropic conductive film 520 may bond the third pad PE2a of the flexible printed circuit board 200 and the fourth pad PE2b of the printed circuit board (PCB) 300, and at the same time may electrically connect them.

[0057] In the following, reference will be made to Figure 3 An anisotropic conductive film included in a display device according to an exemplary embodiment of the present invention is described in detail. Figure 3 An exemplary embodiment according to the present inventive concept is shown. Figure 1 An exploded perspective view of an enlarged portion A of FIG.

[0058] like Figure 3 As shown in the exemplary embodiment of , the first pad PE1a may be disposed on the upper surface of the substrate 110, and the second pad PE1b may be disposed on the lower surface of the flexible printed circuit board 200. The second pad PE1b may be disposed in an area overlapping with the first pad PE1a. However, in the exemplary embodiment, the first pad PE1a and the second pad PE1b may be completely aligned or may not completely overlap, may deviate to a certain extent, and may differ in size or shape. In addition, the first pad PE1a and the second pad PE1b may have a variety of shapes such as a polygonal shape, a circular shape, and an elliptical shape. Figure 3In the exemplary embodiment shown in FIG. 1 , the first pad PE1a and the second pad PE1b each include three rectangular pads spaced apart from each other. However, in alternative embodiments, the first pad PE1a and the second pad PE1b may include different shapes and arrangements, and may each include only a single pad.

[0059] The first anisotropic conductive film 510 may be disposed between the first pad PE1a and the second pad PE1b. The first anisotropic conductive film 510 may have a first surface in contact with the first pad PE1a and a second surface in contact with the second pad PE1b.

[0060] The first anisotropic conductive film 510 may include a conductive polymer. For example, in an exemplary embodiment, the first anisotropic conductive film 510 may include at least one of polyacetylene, polypyrrole, polythiophene, polyphenylene vinylene, and polyphenylene.

[0061] The first anisotropic conductive film 510 may include at least one conductive region 511 and at least one insulating region 512. The conductive region 511 is a region where current flows, and the insulating region 512 is a region where current hardly flows. For example, the resistance of the conductive region 511 may exceed 0Ω and may be equal to or less than 10Ω. 5 Ω, and the resistance of the insulating region 512 may be 10 6 Ω to 10 7 Ω.

[0062] The conductive region 511 may be disposed in a region where the first pad PE1a and the second pad PE1b overlap each other. The conductive region 511 may electrically connect the first pad PE1a and the second pad PE1b that overlap each other. In addition, the plurality of conductive regions 511 in the first anisotropic conductive film 510 may be separated and disposed by the insulating region 512 and may be insulated from each other without being electrically connected to each other. For example, in Figure 3 In the exemplary embodiment shown in FIG. 5 , the conductive region 511 is three rectangular regions spaced apart from each other and substantially aligned with the first and second pads PE1a and PE1b. However, the conductive region 511 may have different shapes and arrangements, and may include only a single region in some embodiments.

[0063] For example, the conductive region 511 may have various shapes such as a polygonal shape, a circular shape, an elliptical shape, etc. Figure 3The conductive regions 511 are shown to be aligned with the first pad PE1a and the second pad PE1b, but they are not limited thereto, and the conductive regions 511 may not be completely aligned with the first pad PE1a and the second pad PE1b. For example, the conductive regions 511 may not completely overlap with the first pad PE1a and the second pad PE1b, and they may be slightly offset from each other. Each of the conductive regions 511 may overlap only one corresponding first pad PE1a and one corresponding second pad PE1b, and may not overlap with another first pad PE1a or second pad PE1b.

[0064] The insulating region 512 may be disposed in a region where the first pad PE1a and the second pad PE1b do not overlap, and may be disposed in a region other than the conductive region 511 to surround the conductive region 511. The insulating region 512 may have different shapes and sizes. The insulating region 512 may include a single region or a plurality of regions spaced apart from each other. In addition, the insulating region 512 may not overlap the first pad PE1a and the second pad PE1b. The first pad PE1a disposed on the substrate 110 of the display panel 100 may not be short-circuited to each other due to the insulating region 512 of the first anisotropic conductive film 510, and may not transmit an electrical signal.

[0065] For example, when the first anisotropic conductive film 510 includes polyacetylene, the conductive region 511 may include trans-polyacetylene, and the insulating region 512 may include cis-polyacetylene. In this embodiment, the conductivity of the conductive region 511 is 10 -4 S / cm to 10 -2 S / cm, and the conductivity of the insulating region 512 is 10 -8 S / cm to 10 -6 Therefore, the conductive region 511 may transmit an electrical signal between the first pad PE1 a and the second pad PE1 b , and the electrical signal is cut off by the insulating region 512 .

[0066] In the case of known existing devices having an anisotropic conductive film including conductive balls, the display panel and the flexible printed circuit board can be connected through physical point contacts through the conductive balls. In addition, the size of the conductive balls may not be infinitely small, and the conductive balls may have a certain size and volume and be irregularly arranged in the anisotropic conductive film. For example, the minimum size of the conductive balls may be about 3 μm.

[0067] Connection failure of the pads may occur due to the above-described conductive ball characteristics. For example, when the conductive balls are excessively concentrated in some areas, the pads located in the direction of the surface of the display panel may be short-circuited, and when the number of conductive balls is insufficient in some areas, the display panel and the flexible printed circuit board may not be electrically connected to each other.

[0068] In addition, the pitch of the pads and the area of ​​the pads may be limited to a specific size or larger to allow facing pads to be electrically connected to each other by using conductive balls while preventing adjacent pads from being electrically connected. Therefore, it is difficult to implement a high-resolution display device, and there is a limitation in reducing the dead space in the high-resolution display device. The dead space is an area other than the display area DA where an image is displayed in the display device 10, and may be the same area as the non-display area NA, or may be an area including the non-display area NA.

[0069] However, in the first anisotropic conductive film 510 according to the exemplary embodiment of the inventive concept, the first pad PE1a of the display panel 100 and the second pad PE1b of the flexible printed circuit board 200 can be electrically connected to each other by including the conductive region 511 having high conductivity and the insulating region 512 having low conductivity without including the conductive balls. Therefore, defects caused by including the conductive balls and restrictions on the pitch and area of ​​the pads are prevented. The pads can also include a small pitch and area.

[0070] For example, the pitch P1 of the first pad PE1a and the pitch P2 of the second pad PE1b may be less than 27 μm. The pitch indicates the distance between the centers of the pads. Therefore, the distance P3 between the centers of the conductive regions 511 of the first anisotropic conductive film 510 may be less than 27 μm.

[0071] Although Figure 3 It only describes Figure 2 The first anisotropic conductive film 510, but Figure 3 The content of can be similarly applied to Figure 2 The second anisotropic conductive film 520 connects the third pad PE2a and the fourth pad PE2b.

[0072] In the following, reference will be made to Figure 4 An anisotropic conductive film included in a display device according to an exemplary embodiment of the present invention is described. Figure 4 An exploded perspective view of a display apparatus according to an exemplary embodiment of the inventive concept is illustrated. Figure 4 Shown with Figure 1 The same area as area A.

[0073] In addition to including silicon, the first anisotropic conductive film 510 is Figure 3 The first anisotropic conductive film 510 is similar to the first anisotropic conductive film 510. Therefore, detailed description of the repeated contents will be omitted.

[0074] The first anisotropic conductive film 510 may include a conductive region 511 and an insulating region 512. The conductive region 511 is a region through which current flows, and the insulating region 512 is a region in which current hardly flows.

[0075] According to the present exemplary embodiment, the conductive region 511 of the first anisotropic conductive film 510 included in the display device 10 may include polycrystalline silicon 555. The insulating region 512 may include amorphous silicon 550. The polycrystalline silicon 555 is an aggregate of single crystal silicon regions. The electron mobility of the polycrystalline silicon 555 is about 100 times higher than that of the amorphous silicon 550. The conductive region 511 of the first anisotropic conductive film 510 including the amorphous silicon 550 may be formed by selectively crystallizing the amorphous silicon into the polycrystalline silicon 555 using an excimer laser. Compared with the electron mobility of the insulating region 512, the conductive region 511 may have excellent electron mobility.

[0076] In an exemplary embodiment, the first anisotropic conductive film 510 may further include a resin. The resin may be a thermosetting resin or a photocurable resin. For example, the resin may be an epoxy resin, an acrylic resin, a polyester resin, a bismaleimide resin, or a cyanate resin. The electron mobility may be lower when the first anisotropic conductive film 510 includes the resin than when the first anisotropic conductive film 510 does not include the resin. The electron mobility of the first anisotropic conductive film 510 may be controlled by adjusting the density of silicon particles included in the resin.

[0077] The first pads PE1a disposed on the upper surface of the substrate 110 and the second pads PE1b disposed on the lower surface of the flexible printed circuit board 200 may be bonded to the conductive region 511 of the first anisotropic conductive film 510 to be electrically connected to each other. The pitch P1 of the first pads PE1a and the pitch P2 of the second pads PE1b may be less than 27 μm. Therefore, the distance P3 between the centers of the conductive regions 511 of the first anisotropic conductive film 510 may be less than 27 μm.

[0078] Although Figure 4 It only describes Figure 2 The first anisotropic conductive film 510, but Figure 4 The features shown in the exemplary embodiment of FIG. 5 can be similarly applied to the second anisotropic conductive film 520 .

[0079] Now refer to Figure 5 A method for manufacturing a display device according to an exemplary embodiment is described. Specifically, a method for attaching a flexible printed circuit board to a display panel included in the display device using an anisotropic conductive film will be described. Figure 5 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment.

[0080] A display panel and a flexible printed circuit board having pads may be prepared (S101). The pads of the display panel and the pads of the flexible printed circuit board may be formed at positions overlapping each other.

[0081] An anisotropic conductive film may be attached to a pad portion of the display panel (S102). The anisotropic conductive film may be a film including a conductive polymer. For example, the anisotropic conductive film may include at least one of polyacetylene, polypyrrole, polythiophene, polyphenylene vinylene, and polyphenylene.

[0082] A mask may be prepared on the anisotropic conductive film (S103). The mask may be used to selectively and locally irradiate the laser to a predetermined area of ​​the anisotropic conductive film. The mask may be provided on the anisotropic conductive film, and may include an opening in an area corresponding to a pad of the display panel. Therefore, the laser may be irradiated only locally in an area where the anisotropic conductive film overlaps with the pad of the display panel. Specifically, alignment of the pad area is easily performed by using a mask, which allows the laser to be accurately irradiated to an area corresponding to a pad having a small pitch. Therefore, a pad having a small pitch and area may be formed, and a high-resolution and highly integrated display device may be manufactured.

[0083] The laser may be irradiated to the anisotropic conductive film (S104). The irradiation of the laser may be performed by irradiating the laser only to a region where the anisotropic conductive film overlaps with a pad of the display panel.

[0084] The bonds of the conductive polymer can be deformed to increase the conductivity in the area irradiated by the laser. For example, in step S102 of attaching the anisotropic conductive film to the pad portion of the display panel, the anisotropic conductive film attached to the display panel may be a film including cis-polyacetylene. When heat of about 180°C is applied to cis-polyacetylene, the bonds are deformed to form trans-polyacetylene having a geometric isomer relationship. Therefore, when the laser is irradiated to the film including cis-polyacetylene, trans-polyacetylene is formed in the area irradiated by the laser. In other words, the area irradiated by the laser includes trans-polyacetylene, and the area not irradiated by the laser includes cis-polyacetylene.

[0085] The conductivity of trans-polyacetylene is higher than that of cis-polyacetylene. For example, the conductivity of trans-polyacetylene is 10 - 4 S / cm to 10 -2 S / cm, and the conductivity of cis-polyacetylene is 10 -8 S / cm to 10 -6 S / cm. Therefore, the area irradiated with laser light can be used as a conductive area that transmits electrical signals, and the other areas can be used as insulating areas that do not transmit electrical signals.

[0086] Although the anisotropic conductive film is described as including a conductive polymer, the anisotropic conductive film may include silicon particles. In this embodiment, amorphous silicon can be crystallized into polycrystalline silicon by irradiating an anisotropic conductive film including amorphous silicon with an excimer laser. The electron mobility of polycrystalline silicon is about 100 times higher than that of amorphous silicon. Therefore, the region including polycrystalline silicon by irradiating the laser thereto can be used as a conductive region, and the region including amorphous silicon can be used as an insulating region.

[0087] The flexible printed circuit board may be attached to the anisotropic conductive film (S105). For example, the pads of the flexible printed circuit board may overlap with the laser-irradiated area of ​​the anisotropic conductive film. As previously described, the pads of the display panel, the pads of the flexible printed circuit board, and the conductive area of ​​the anisotropic conductive film irradiated with the laser may overlap to be electrically connected to each other. In addition, pads adjacent to each other in the planar direction may be insulated from each other by the insulating area of ​​the anisotropic conductive film.

[0088] Now refer to Figure 6 A method of manufacturing a display device according to another exemplary embodiment of the inventive concept is described. Figure 6 is a flowchart illustrating a method of manufacturing a display device according to an exemplary embodiment. Figure 6 The manufacturing method and Figure 5 The manufacturing method is similar and detailed description of redundant constituent elements will be omitted.

[0089] A display panel and a flexible printed circuit board having a pad may be prepared (S201). An anisotropic conductive film may be attached to a pad portion of the flexible printed circuit board. The anisotropic conductive film may be a film including a conductive polymer, or may include silicon particles.

[0090] An anisotropic conductive film may be attached to a pad portion of a flexible printed circuit board (S202). A mask may be set on the anisotropic conductive film (S203). Laser may be irradiated onto the anisotropic conductive film (S204). Irradiation of the laser may be performed by irradiating the laser only onto an area where the anisotropic conductive film overlaps with the pad of the flexible printed circuit board using a mask.

[0091] Next, the display panel may be attached to the anisotropic conductive film (S205). In this embodiment, the pad of the display panel overlaps with the region of the anisotropic conductive film to which the laser is irradiated.

[0092] The method described herein may also include a step of attaching a second anisotropic conductive film to a second pad portion of a flexible printed circuit board or a printed circuit board in a similar manner as previously described with respect to the first anisotropic conductive film. As previously described with respect to the first anisotropic conductive film, a mask may be prepared on the second anisotropic conductive film to form at least one conductive region and at least one insulating region. The second anisotropic conductive film bonds and electrically connects the second pad portion of the flexible printed circuit board to the printed circuit board.

[0093] While exemplary embodiments of the inventive concept have been described in conjunction with what are presently considered to be practical exemplary embodiments, it will be understood that the invention is not limited to the disclosed exemplary embodiments, but on the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. Display equipment, including: Display panel; a flexible printed circuit board electrically connected to the display panel; A first pad is arranged on the display panel; A second pad is disposed on the flexible printed circuit board and overlaps with the first pad; as well as a first anisotropic conductive film disposed between the first pad and the second pad, wherein the first anisotropic conductive film is configured to bond the first pad to the second pad, The first anisotropic conductive film includes a first insulating region and a first conductive region configured to electrically connect the first pad and the second pad. wherein the first conductive region comprises trans-polyacetylene, the first insulating region comprises cis-polyacetylene, and Wherein, the first insulating region is arranged adjacent to the first conductive region.

2. The display device according to claim 1, wherein: The first conductive region is disposed in a region where the first pad and the second pad overlap, and The first insulating region is disposed in a region surrounding the first conductive region.

3. The display device according to claim 2, wherein: The first pads have a pitch of 27 μm or less.

4. The display device according to claim 2, further comprising: Printed circuit boards; A third pad is provided on the flexible printed circuit board; as well as The fourth pad is arranged on the printed circuit board.

5. The display device according to claim 4, further comprising: A second anisotropic conductive film is disposed between the third pad and the fourth pad, and the second anisotropic conductive film is configured to couple the third pad to the fourth pad.

6. The display device according to claim 5, wherein: The second anisotropic conductive film includes a conductive polymer.

7. The display device according to claim 6, wherein: The second anisotropic conductive film includes a second insulating region and a second conductive region configured to electrically connect the third pad and the fourth pad, and The second conductive region is disposed in a region where the third pad and the fourth pad overlap.

8. The display device according to claim 7, wherein: The flexible printed circuit board includes a data driver integrated circuit.

9. The display device according to claim 8, wherein: The data driver integrated circuit is configured to transmit a signal to the display panel through the second pad, the first anisotropic conductive film, and the first pad.

10. Display equipment, including: Display panel; a flexible printed circuit board electrically connected to the display panel; A first pad is arranged on the display panel; A second pad is disposed on the flexible printed circuit board and overlaps with the first pad; as well as a first anisotropic conductive film disposed between the first pad and the second pad, wherein the first anisotropic conductive film is configured to bond the first pad to the second pad, The first anisotropic conductive film includes a first insulating region and a first conductive region configured to electrically connect the first pad to the second pad. The first conductive region includes polysilicon, and The first insulating region includes amorphous silicon.

11. The display device according to claim 10, wherein: The first conductive region is disposed in a region where the first pad and the second pad overlap, and The first insulating region is disposed in a region surrounding the first conductive region.

12. The display device according to claim 11, wherein: The first anisotropic conductive film further includes a thermosetting resin or a photocurable resin.

13. The display device according to claim 12, further comprising: Printed circuit boards; A third pad is provided on the flexible printed circuit board; A fourth pad is provided on the printed circuit board; as well as The second anisotropic conductive film is disposed between the third pad and the fourth pad.

14. The display device according to claim 13, wherein: The second anisotropic conductive film includes a second insulating region and a second conductive region configured to electrically connect the third pad to the fourth pad, The second conductive region includes polysilicon, and The second insulating region includes amorphous silicon.

15. The display device according to claim 14, wherein: The second anisotropic conductive film further includes a thermosetting resin or a photocurable resin.

16. A method for manufacturing a display device, the method comprising: Providing display panels and flexible printed circuit boards; attaching an anisotropic conductive film to the display panel or the flexible printed circuit board; disposing a mask on the anisotropic conductive film, wherein the mask includes an opening in a region corresponding to a pad of the display panel or a pad of the flexible printed circuit board; and irradiating the anisotropic conductive film with a laser through the opening of the mask to irradiate the laser onto a region of the anisotropic conductive film overlapping with the pad of the display panel or the pad of the flexible printed circuit board, the laser increasing the conductivity of the anisotropic conductive film to form a conductive region located in a region irradiated with the laser and an insulating region located in a region not irradiated with the laser, Wherein, the insulating area is arranged adjacent to the conductive area.

17. The manufacturing method according to claim 16, wherein: The anisotropic conductive film includes a conductive polymer.

18. The manufacturing method according to claim 16, wherein: The region of the anisotropic conductive film irradiated by the laser includes polysilicon; and The region of the anisotropic conductive film that is not irradiated by the laser includes amorphous silicon.

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