JP2019158963A - Display device - Google Patents

Abstract

An object of the present invention is to suppress defects in terminals and improve the yield of display devices. SOLUTION: A display device according to one embodiment includes a substrate having a display area in which pixels are arranged and a peripheral area around the display area, a plurality of pads arranged in the peripheral area, and the peripheral area. and a plurality of wirings arranged in the substrate and electrically connected to each of the plurality of pads. The wiring extends to the edge of the substrate. At the edge, the thickness of the substrate at the location of the wiring is a first thickness, and the thickness of the substrate between the adjacent wirings is a second thickness less than the first thickness. be. [Selection drawing] Fig. 7

Description

  Embodiments described herein relate generally to a display device.

  For example, in a display device such as an organic electroluminescence (EL) display device or a liquid crystal display device, a terminal for connecting to an external circuit is arranged on a substrate provided with elements such as electrodes and switching elements constituting a pixel. Yes.

  Conventionally, it has been common to use glass for the substrate of a display device. In recent years, a technique for realizing a flexible display device by forming a substrate from a resin material has been proposed.

  For example, in the manufacturing process of a display device, when a substrate formed of a resin material is cut with a laser beam, a part of the substrate may be carbonized in the vicinity of the cutting line. When such carbonization occurs in the vicinity of the terminal, a plurality of terminals and a plurality of wirings can be conducted through the carbonized portion.

  In addition, the terminal is connected to an external circuit through, for example, a conductive adhesive layer. If the adhesive force between the adhesive layer and the terminal is insufficient, conduction failure between the external circuit and the terminal may occur.

JP, 2014-41187, A JP-A-11-327465

Due to the above-described problems of various terminals, there is a concern that the yield of the display device may be reduced. Therefore, a technique capable of suppressing the failure of the terminal has been desired.
One of the objects of the present disclosure is to suppress terminal defects and improve the yield of display devices.

  A display device according to an embodiment is arranged in a substrate having a display area in which pixels are arranged, a peripheral area around the display area, a plurality of pads arranged in the peripheral area, and the peripheral area. And a plurality of wirings electrically connected to each of the plurality of pads. The wiring extends to the end of the substrate. At the end, the thickness of the substrate at the position of the wiring is a first thickness, and the thickness of the substrate between the adjacent wirings is a second thickness smaller than the first thickness. is there.

FIG. 1 is a plan view illustrating a schematic configuration of the display device according to the first embodiment. FIG. 2 is a diagram illustrating an example of a circuit configuration of the sub-pixel. FIG. 3 is a schematic cross-sectional view of the display device taken along line III-III in FIG. FIG. 4 is a plan view illustrating a schematic structure in the vicinity of the terminal. FIG. 5 is a schematic cross-sectional view of the display device taken along line VV in FIG. FIG. 6 is a schematic cross-sectional view of the display device taken along line VI-VI in FIG. FIG. 7 is a schematic cross-sectional view of the display device taken along line VII-VII in FIG. FIG. 8 is a schematic cross-sectional view of the display device taken along line VIII-VIII in FIG. FIG. 9A is a cross-sectional view including wiring, illustrating an example of a manufacturing process of the display device. FIG. 9B is a cross-sectional view between adjacent wirings, illustrating an example of a manufacturing process of the display device. FIG. 10A is a cross-sectional view showing a manufacturing step that follows FIG. 9A. FIG. 10B is a cross-sectional view showing a manufacturing step that follows FIG. 9B. FIG. 11A is a cross-sectional view showing a manufacturing step that follows FIG. 10A. FIG. 11B is a cross-sectional view showing a manufacturing step that follows FIG. 10B. FIG. 12A is a cross-sectional view showing a manufacturing step that follows FIG. 11A. FIG. 12B is a cross-sectional view showing a manufacturing step that follows FIG. 11B. FIG. 13 is a schematic cross-sectional view taken along lines and pads of a display device according to a comparative example. FIG. 14 is a cross-sectional view between adjacent wirings of a display device according to a comparative example. FIG. 15 is a cross-sectional view including a plurality of wirings of a display device according to a comparative example. FIG. 16 is a schematic cross-sectional view taken along lines and pads of the display device according to the second embodiment. FIG. 17 is a cross-sectional view including a plurality of wirings of the display device according to the second embodiment. FIG. 18 is a cross-sectional view including a plurality of wirings and a plurality of pads of the display device according to the second embodiment.

Several embodiments will be described with reference to the drawings.
It should be noted that the disclosure is merely an example, and those skilled in the art can easily conceive of appropriate changes while maintaining the gist of the invention are naturally included in the scope of the present invention. In addition, the drawings may be schematically represented in comparison with actual modes in order to clarify the description, but are merely examples, and do not limit the interpretation of the present invention. In each drawing, the reference numerals may be omitted for the same or similar elements arranged in succession. In addition, in the present specification and each drawing, components that perform the same or similar functions as those described above with reference to the previous drawings are denoted by the same reference numerals, and redundant detailed description may be omitted.

  In each embodiment, a display device having an organic electroluminescence (EL) display element is illustrated. However, each embodiment does not preclude the application of the individual technical ideas disclosed in each embodiment to other types of display devices. For example, as other types of display devices, there are liquid crystal display devices, electronic paper type display devices having electrophoretic elements, display devices applying Micro Electro Mechanical Systems (MEMS), display devices applying electrochromism, and the like. Can be mentioned.

[First Embodiment]
FIG. 1 is a plan view showing a schematic configuration of a display device 1 according to the first embodiment. The display device 1 includes a substrate 2, an optical film 3, and a connection member 4. In the present embodiment, a first direction X, a second direction Y, and a third direction Z are defined as illustrated. The first direction X, the second direction Y, and the third direction Z intersect each other vertically, for example, but may intersect at an angle other than perpendicular. The first direction X and the second direction Y correspond to directions parallel to the main surface of the substrate 2. The third direction Z corresponds to the thickness direction of the substrate 2. In the present disclosure, viewing the display device 1 in parallel with the third direction Z is referred to as planar view.

  The substrate 2 includes a display area DA for displaying an image and a peripheral area PA around the display area DA. The display area DA has a large number of pixels PX arranged in the first direction X and the second direction Y. The pixel PX includes a plurality of subpixels SP corresponding to different colors. In the example of FIG. 1, the pixel PX includes a subpixel SPR corresponding to red, a subpixel SPG corresponding to green, and a subpixel SPB corresponding to blue. The subpixels SPR, SPG, and SPB are arranged in the first direction X, for example. The form of the pixel PX is not limited to this example, and may include sub-pixels of other colors such as white.

  The substrate 2 has a rectangular shape having a first end E1, a second end E2, a third end E3, and a fourth end E4. The first end E1 and the second end E2 are parallel to the first direction X. The third end E3 and the fourth end E4 are parallel to the second direction Y. The substrate 2 may have a shape other than a rectangle, such as a regular circle, an ellipse, or a polygon other than a rectangle. In the example of FIG. 1, the display area DA is also rectangular, but may be another shape similar to the substrate 2.

  The substrate 2 has a terminal TM in the peripheral area PA. In the example of FIG. 1, the terminal TM is arranged along the first end E1. The terminal TM includes a plurality of pads P arranged in the first direction X. A wiring L is connected to each pad P. For example, the wiring L includes a wiring for supplying a video signal applied to the subpixel SP. The connection member 4 is electrically connected to the terminal TM. The connection member 4 is, for example, a flexible circuit board, but may be another type of member as long as it connects the display device 1 to an external circuit.

  The optical film 3 is affixed to the display area DA. The optical film 3 has specific optical functions, such as a polarizing layer that passes a specific polarization component of light and absorbs other polarization components, a retardation layer that gives a phase difference to light, and a diffusion layer that diffuses light. Contains one or more layers. The optical film 3 may be a protective film that protects the display area DA.

  FIG. 2 is a diagram illustrating an example of a circuit configuration of the sub-pixel SP. The sub-pixel SP includes an organic EL element OLED, a first switching element SW1, and a second switching element SW2.

  The anode electrode AE of the organic EL element OLED is connected to the power supply line PL via the first switching element SW1. The cathode electrode CE of the organic EL element OLED is grounded. A storage capacitor CS is formed between the gate electrode and the source electrode (or drain electrode) of the first switching element SW1. The gate electrode of the first switching element SW1 is connected to the video line DL to which the video signal is supplied via the second switching element SW2. The gate electrode of the second switching element SW2 is connected to the scanning line G. For example, each of the switching elements SW1 and SW2 can be composed of a polysilicon thin film transistor.

  FIG. 3 is a schematic cross-sectional view of the display device 1 taken along line III-III in FIG. Here, cross sections of the sub-pixels SPR, SPG, and SPB are shown. Since the subpixels SPR, SPG, and SPB have the same configuration, the constituent elements of the subpixel SPG are mainly denoted by reference numerals, and the constituent elements of the subpixels SPR and SPB are omitted.

  The display device 1 includes a substrate 2, an insulating layer 5, a planarizing layer 6, a rib 7, a sealing layer SL, first to third passivation layers PV1 to PV3, an optical film 3, and an adhesive layer AD. And. Furthermore, the display device 1 includes a first switching element SW1, an organic EL element OLED, and a reflective layer RF as elements disposed in each subpixel SP. Note that the second switching element SW2 is not shown. Organic EL elements OLED of adjacent subpixels SP are partitioned by ribs 7.

  The substrate 2 is formed of a resin material such as polyimide, polyester, or polycarbonate and has flexibility. The substrate 2 has a first surface F1 and a second surface F2 opposite to the first surface F1.

  The insulating layer 5 includes a first insulating layer 51 (undercoat layer), a second insulating layer 52 (gate insulating film), and a third insulating layer 53 (interlayer insulating film). The first insulating layer 51 covers the first surface F1 of the substrate 2. A semiconductor layer SC of the first switching element SW1 is formed on the first insulating layer 51. The second insulating layer 52 covers the first insulating layer 51 and the semiconductor layer SC. The gate electrode GE of the first switching element SW1 is formed on the second insulating layer 52. The third insulating layer 53 covers the second insulating layer 52 and the gate electrode GE. The source electrode SE and the drain electrode DE of the first switching element SW1 are formed on the third insulating layer 53 and are in contact with the semiconductor layer SC through contact holes formed in the insulating layers 52 and 53.

  The planarization layer 6 covers the third insulating layer 53, the source electrode SE, and the drain electrode DE. The planarization layer 6 planarizes unevenness caused by the first switching element SW1 and the second switching element SW2. The first passivation layer PV <b> 1 is formed on the planarization layer 6. The reflective layer RF is formed on the first passivation layer PV1. For example, the reflective layer RF can be formed of a material having a high light reflectance such as aluminum or silver.

  The anode electrode AE (pixel electrode) of the organic EL element OLED is formed on the reflective layer RF. The anode electrode AE is in contact with the drain electrode DE through a contact hole that penetrates the first passivation layer PV1 and the planarization layer 6. The rib 7 is formed on the first passivation layer PV1 and the anode electrode AE. The organic light emitting layer ORG is formed on the anode electrode AE between the adjacent ribs 7. The cathode electrode CE (common electrode) covers the rib 7 and the organic light emitting layer ORG. The cathode electrode CE is continuously formed across the plurality of subpixels SP. The second passivation layer PV2 covers the cathode electrode CE.

  The sealing layer SL is formed on the second passivation layer PV2. The sealing layer SL covers the organic light emitting layer ORG together with the second passivation layer PV2 and the cathode electrode CE. The third passivation layer PV3 is formed on the sealing layer SL. The optical film 3 is bonded to the third passivation layer PV3 through a transparent adhesive layer AD.

  The planarization layer 6, the rib 7 and the sealing layer SL can be formed of, for example, an insulating organic resin material. Each of the passivation layers PV1 to PV3 can be formed of an insulating inorganic resin material such as SiN. The anode electrode AE and the cathode electrode CE can be formed of a transparent conductive material such as ITO (indium tin oxide). The material of each element is not limited to the examples given above.

  When a video signal is supplied to the anode electrode AE via the first switching element SW1, a potential difference is generated between the anode electrode AE and the cathode electrode CE. Due to this potential difference, the organic light emitting layer ORG emits light. For example, the color emitted from the organic light emitting layer ORG of the subpixel SPR is red, the color emitted from the organic light emitting layer ORG of the subpixel SPG is green, and the color emitted from the organic light emitting layer ORG of the subpixel SPB is blue. The light emitted from the organic light emitting layer ORG of each of the subpixels SPR, SPG, and SPB may be the same color (for example, white), and a color filter may be disposed above the sealing layer SL.

  Subsequently, the structure in the vicinity of the terminal TM will be described. FIG. 4 is a plan view illustrating a schematic structure in the vicinity of the terminal TM. Here, the pad P and the wiring L included in the substrate 2 are shown, and the connection member 4 is shown by a chain line. Furthermore, an anisotropic conductive film ACF that electrically connects the connection member 4 and the pad P is shown with a dot pattern. The anisotropic conductive film ACF also serves as an adhesive layer that bonds the connection member 4 and the pad P together.

  The pad P has an elongated shape in the second direction Y. The width of the pad P in the first direction X is larger than the width of the wiring L in the first direction X. The pads P are arranged in the first direction X at regular intervals. A predetermined interval is provided between the pad P and the first end E1. The wiring L overlaps with the pad P. The wiring L extends to the first end E1. In addition, the shape and arrangement | positioning aspect of the pad P and the wiring L are not restricted to what was illustrated here.

  The connection member 4 overlaps with each pad P. The anisotropic conductive film ACF is disposed between the pad P and the connection member 4. In the example of FIG. 4, the edge of the anisotropic conductive film ACF on the display area DA side (upper side in the figure) and the edge on the first end E1 side (lower side in the figure) both overlap the pad P. However, the anisotropic conductive film ACF may be provided in a wider range.

  In the example of FIG. 4, the end of the connection member 4 overlaps both the anisotropic conductive film ACF and the pad P. The end portion of the connection member 4 may be located closer to the display area DA (upper side in the drawing) than the pad P or the anisotropic conductive film ACF.

  FIG. 5 is a schematic cross-sectional view of the display device 1 taken along the line VV in FIG. FIG. 6 is a schematic cross-sectional view of the display device 1 taken along the line VI-VI in FIG. 5 includes the wiring L and the pad P, and the cross-sectional view of FIG. 6 does not include the wiring L and the pad P.

  As shown in FIG. 5, the wiring L is disposed on the upper surface of the substrate 2, and the pad P is disposed on the wiring L. The wiring L and the pad P can be formed of a metal material, for example. The wiring L and the pad P may have a single layer structure or a multilayer structure. Further, the wiring L and the pad P may include a transparent conductive material such as ITO. In the example of FIG. 5, the thickness of the pad P is larger than the thickness of the wiring L, but is not limited to this example.

  As shown in FIGS. 5 and 6, the wiring L, the pad P, and the upper surface of the substrate 2 are covered with an insulating layer 10. The insulating layer 10 has an opening 12 that overlaps the pad P in plan view. A part of the pad P is exposed from the insulating layer 10 through the opening 12. The opening 12 may have a size such that the entire pad P is exposed from the insulating layer 10.

  For example, the insulating layer 10 can be formed of the same material and the same process as the rib 7 shown in FIG. As another example, the insulating layer 10 may be formed by the same process using the same material as the planarizing layer 6 or the sealing layer SL shown in FIG. Further, the insulating layer 10 may be formed in the peripheral region PA by an organic or inorganic resin material by a process different from any of the layers shown in FIG.

  The connection member 4 includes a substrate 40, a wiring 41, and a protective layer 42. The substrate 40 can be formed of a resin material such as polyimide, for example. The wiring 41 can be formed of a metal material such as copper, for example, but may include a transparent conductive material such as ITO. The protective layer 42 is made of, for example, an inorganic or organic resin material. At a position facing the pad P, the wiring 41 is exposed from the protective layer 42.

  The anisotropic conductive film ACF is disposed between the pad P and the wiring 41 and contacts the pad P through the opening 12 and also contacts the wiring 41. Thereby, the pad P and the wiring 41 are conducted. As the anisotropic conductive film ACF, for example, a thermosetting resin containing conductive particles can be used.

  5 and 6, the insulating layer 10 around the opening 12 is located between the anisotropic conductive film ACF and the pad P. Further, a part of the anisotropic conductive film ACF is located between the insulating layer 10 and the protective layer 42.

  As shown in FIGS. 4 to 6, the peripheral area PA includes a first area A1, a second area A2, a third area A3, and a fourth area A4 between the first end E1 and the display area DA. And a fifth region A5. These areas A1 to A5 are arranged in order from the first end E1 toward the display area DA.

  Specifically, the first area A1 is a part of the area between the first end E1 and each pad P. The second region A2 is a region between the first region A1 and the opening 12. The third region A3 is a region corresponding to the opening 12. The fourth area A4 is an area between the opening 12 and a position at a fixed distance from the end of the pad P on the display area DA side. The fifth area A5 is an area between the fourth area A4 and the display area DA.

  In the cross section shown in FIG. 5, that is, at the position where the pad P and the wiring L exist, the thickness of the substrate 2 is constant at the first thickness T1 in each of the regions A1 to A5. On the other hand, in the cross section shown in FIG. 6, that is, between adjacent wirings L, the thickness of the substrate 2 is the first thickness T1 in each of the regions A2, A4, A5, and the first region A1 and the third region A3. The second thickness T2 is smaller than the first thickness T1 (T2 <T1). The second surface F2 of the substrate 2 is generally flat. Accordingly, the thickness of the substrate 2 varies between the first thickness T1 and the second thickness T2, thereby causing unevenness on the first surface F1.

  In both FIG. 5 and FIG. 6, the thickness of the insulating layer 10 is the third thickness T3 in the fifth region A5. The insulating layer 10 has a fourth thickness T4 (T4 <T3) that is smaller than the third thickness T3 in the second region A2 and the fourth region A4, except in the vicinity of the step formed by the pad P. ). The insulating layer 10 does not exist in the first region A1 and the third region A3. In the first region A1, the wiring L is exposed from the insulating layer 10, but the exposed wiring L is not connected to an external circuit such as the connection member 4.

  Since the thickness of the insulating layer 10 is different between the fourth region A4 and the fifth region A5, a step 11 is formed at the boundary between these regions A4 and A5. The step 11 is located between the pad P and the display area DA and functions as a wall for blocking the anisotropic conductive film ACF. That is, even if the anisotropic conductive film ACF shown in FIGS. 5 and 6 flows to the display area DA side (left side in the figure) before curing, it is blocked by the step 11.

  As an example, the distance in the second direction Y from the first end E1 to the pad P is 1.0 mm, the length of the pad P in the second direction Y is 2.0 mm, and the second direction Y of the opening 12 The length in the second direction Y of the part where the insulating layer 10 covers the end of the pad P is 0.5 mm, respectively, and the length in the second direction Y from the pad P to the step 11 is 1.0 mm. The distance is 0.2 mm. However, it is not restricted to the numerical value quoted here, The dimension of each part can be defined suitably.

  As shown in FIG. 5, the substrate 2 includes a carbonized portion C at the first end E1. The carbonized portion C is in contact with the wiring L. The carbonized portion C is formed when the substrate 2 is cut by laser light as will be described later.

  FIG. 7 is a schematic cross-sectional view of the display device 1 taken along line VII-VII in FIG. FIG. 8 is a schematic cross-sectional view of the display device 1 taken along line VIII-VIII in FIG. In these drawings, the connection member 4 and the anisotropic conductive film ACF are not shown.

  As shown in FIG. 7, the carbonized portion C is located below the wiring L in the vicinity of the first end E1. On the other hand, the carbonized portion C does not exist between the adjacent wirings L. The thickness of the substrate 2 including the carbonized portion C is the above-described first thickness T1, and the thickness of the substrate 2 between the adjacent wirings L is the above-described second thickness T2. The substrate 2 has a shape in which a portion having a first thickness T1 and a portion having a second thickness T2 are alternately repeated in the second direction Y. If it says from another viewpoint, the board | substrate 2 has a groove | channel between the adjacent wiring L. FIG.

  The height (T1-T2) at which the substrate 2 protrudes at the position of the wiring L is equal to or greater than the thickness Tc of the carbonized portion C (Tc ≦ (T1-T2)). As an example, the first thickness T1 is 10 μm or more, and the thickness Tc is 5 μm. In this case, the second thickness T2 is preferably smaller than the first thickness T1 by 5 μm or more (T2 ≦ T1-5 μm). Further, from the viewpoint of maintaining the strength of the substrate 2, the second thickness T2 is preferably 5 μm or more (5 μm ≦ T2).

  Note that the carbonized portion C below each wiring L may not have a uniform thickness. In this case, the height (T1-T2) at which the substrate 2 protrudes at the position of the wiring L may be equal to or greater than the average thickness Tave of each carbonized portion C (Tave ≦ (T1-T2)).

  As shown in FIG. 8, the carbonized portion C does not exist at the position of the pad P. Also here, the substrate 2 has a shape in which a portion having a first thickness T1 and a portion having a second thickness T2 are alternately repeated in the second direction Y. 4 and 8, the width of the pad P in the first direction X is larger than the width of the wiring L in the same direction, but the present invention is not limited to this example. For example, the width of the pad P and the wiring L in the first direction X may be the same.

Then, the manufacturing method of the display apparatus 1 is demonstrated below.
9A and 9B are cross-sectional views showing an example of the manufacturing process. 9A is a cross section including the wiring L as in FIG. 5, and FIG. 9B is a cross section between adjacent wirings L as in FIG. In the stages shown in these drawings, the substrate 2, the wiring L, the pad P, and the insulating layer 10 are formed on the glass substrate GL. In the display area DA, the insulating layer 5, the planarizing layer 6, the rib 7, the sealing layer SL, the first to third passivation layers PV1 to PV3, the first switching element SW1, and the organic EL element shown in FIG. An OLED and a reflective layer RF are formed.

  The glass substrate GL is cut from, for example, a mother glass having a larger size, and has an end E0 that protrudes in the second direction Y from the first end E1. The substrate 2, the wiring L, and the insulating layer 10 are formed up to the end E0. An inspection pad may be provided on the wiring L in the vicinity of the end E0. In addition, along the end E0 and the other end of the glass substrate GL, there is an annular guard ring that protects each element of the display area DA and each element of the circuit arranged around it from static electricity generated in the manufacturing process. It may be provided.

  The substrate 2, the wiring L, and the insulating layer 10 in the vicinity of the end E0 are cut along the cutting line CL. For example, the cutting can be performed by irradiating UV laser light from the first surface F1 side of the substrate 2, but other methods may be used.

  Before or after the cutting along the cutting line CL, the portion 10a existing in the first region A1 and the portion 10b existing in the third region A3 of the insulating layer 10 are removed. This removal can be performed by dry etching, for example, but an appropriate method according to the material of the insulating layer 10 may be applied. Note that the portions 10a and 10b may be thinned without completely removing the portions 10a and 10b.

  10A and 10B are cross-sectional views showing manufacturing steps subsequent to FIGS. 9A and 9B, respectively. By removing the above-described portions 10a and 10b, the wiring L and the substrate 2 are exposed from the insulating layer 10 in the first region A1. Furthermore, an opening 12 is formed in the third region A3, and the pad P and the substrate 2 are exposed from the insulating layer 10.

  A first end E1 is formed by cutting along the cutting line CL. For example, a part of the substrate 2 is carbonized by the action of laser light at the time of cutting, and the carbonized portion C described above is formed. At this time, the carbonized portion C exists not only below the wiring L as shown in FIG. 10A but also in a region between adjacent wirings L as shown in FIG. 10B.

  11A and 11B are cross-sectional views showing manufacturing steps subsequent to FIGS. 10A and 10B, respectively. Here, the insulating layer 10 and the substrate 2 in each of the regions A1 to A4 are thinned by, for example, etching.

  Specifically, as shown in FIGS. 11A and 11B, by removing the portion 10c existing in the second region A2 of the insulating layer 10 and the portion 10d existing in the fourth region A4, these regions A2, The A4 insulating layer 10 is thinned. At the same time, as shown in FIG. 11B, the portion 2a existing in the first region A1 of the substrate 2 and the portion 2b existing in the third region A3 are removed, so that the substrate 2 in these regions A1 and A3 is thinned. To do.

  In the cross section of FIG. 11A, since the pad P and the wiring L exist, the substrate 2 is not thinned. Accordingly, the carbonized portion C below the wiring L remains as it is. On the other hand, in the cross section of FIG. 11B, the carbonized portion C is removed by thinning the substrate 2 in the first region A1.

  12A and 12B are cross-sectional views showing manufacturing steps subsequent to FIGS. 11A and 11B, respectively. Here, an uncured anisotropic conductive film ACF is applied so as to close the opening 12. Further, by pressing the heated tool HT heated from above the connection member 4, the pad P and the wiring 41 of the connection member 4 are electrically connected via the anisotropic conductive film ACF and the anisotropic conductive film ACF. Is cured. The anisotropic conductive film ACF may be formed in a tape shape.

  As shown in FIG. 12A, around the opening 12, the insulating layer 10 is thinned to the above-described fourth thickness T4. Therefore, the difference in height between the upper surface of the pad P and the upper surface of the insulating layer 10 around the opening 12 is reduced, and the adhesion of the anisotropic conductive film ACF is improved. The portion covering the pad P of the anisotropic conductive film ACF mainly contributes to the pressure bonding with the connection member 4.

  On the other hand, as shown in FIG. 12B, in the position where the pad P does not exist, the substrate 2 below the opening 12 is thinned, so that the upper surface of the substrate 2 and the upper surface of the insulating layer 10 around the opening 12 The height difference becomes large. Thereby, the fluidity | liquidity of the anisotropic conductive film ACF which does not contribute to the crimping | compression-bonding with the connection member 4 improves.

  By removing the aforementioned portion 10d from the insulating layer 10, a step 11 is formed. Therefore, even when the anisotropic conductive film ACF flows to the display area DA side (left side in the figure) when the hot tool HT is pressed, it is blocked by the step 11.

  When the laser beam LZ is irradiated from below the glass substrate GL, the glass substrate GL and the substrate 2 are peeled off. Thus, the display apparatus 1 having the structure shown in FIGS. 5 and 6 is obtained by removing the glass substrate GL by laser lift-off (LLO).

  In addition, the manufacturing method of the display apparatus 1 is not restricted to what was illustrated above. For example, the glass substrate GL may be peeled off before cutting along the cutting line CL. In this case, the laser beam for cutting may be irradiated from the second surface F2 side of the substrate 2. However, steps such as pressure bonding of the connecting member 4 can be easily performed before the glass substrate GL is peeled off.

  13 to 15 are schematic cross-sectional views of a display device 100 according to a comparative example with the present embodiment. Similar to the display device 1 according to this embodiment, the display device 100 includes a substrate 2, an insulating layer 10, a wiring L, a pad P, a connection member 4, and an anisotropic conductive film ACF. . The cross-sectional view of FIG. 13 represents a cross section along the wiring L and the pad P as in FIG. The cross-sectional view of FIG. 14 represents a cross-section between adjacent wirings L as in FIG. The cross-sectional view of FIG. 15 represents a cross section including a plurality of wirings L in the vicinity of the first end E1 as in FIG.

  As shown in FIGS. 13 and 14, in the display device 100, the substrate 2 is constant at the first thickness T1, and the insulating layer 10 is constant at the third thickness T3. The insulating layer 10 is formed up to the first end E1. A carbonized portion C is formed both below the wiring L and between the adjacent wirings L.

  As shown in FIG. 15, the carbonized portions C are continuously distributed in the first direction X and are in contact with the plurality of wirings L. Therefore, in the example of this figure, a plurality of wirings L are conducted through the carbonized portion C. The carbonized portion C may be locally formed. Even in this case, if the carbonized portion C contacts both of the adjacent wirings L, these wirings L become conductive. For example, when the wiring L becomes conductive, the video signal from the connection member 4 to be supplied to the certain wiring L is also supplied to the other wiring L, and a display defect occurs.

  On the other hand, in this embodiment, the substrate 2 is thinned between the adjacent wirings L as shown in FIG. Thereby, since the carbonized portion C is also removed, the conduction of the wiring L through the carbonized portion C can be suppressed.

  The carbonized portion C may be formed to a depth of 5 μm at the maximum from the surface irradiated with the laser light when the substrate 2 is cut. Therefore, it is preferable that the depth at which the substrate 2 is removed between the adjacent wirings L, in other words, the height (T1-T2) at which the substrate 2 protrudes at the position of the wiring L is 5 μm or more as described above.

  In the comparative example of FIG. 13, the difference in height between the upper surface of the pad P and the upper surface of the insulating layer 10 around the opening 12 is large, so that the adhesion of the anisotropic conductive film ACF in the vicinity of the opening 12 is reduced. Can do. On the other hand, in this embodiment, the insulating layer 10 is thinned around the opening 12. Therefore, as described above, the adhesion of the anisotropic conductive film ACF is improved, and peeling of the connection member 4 and the pad P and poor conduction can be suppressed.

  Thus, according to the present embodiment, various problems in the vicinity of the terminal TM can be suppressed. Thereby, the yield of the display apparatus 1 can be improved. In addition, various suitable effects can be obtained from this embodiment.

[Second Embodiment]
A second embodiment will be described. The configurations not particularly mentioned are the same as those in the first embodiment.
16 to 18 are schematic cross-sectional views of the display device 1 according to the present embodiment. The cross-sectional view of FIG. 16 represents a cross section along the wiring L and the pad P as in FIG. The cross-sectional view of FIG. 17 represents a cross-section (cross-section of the first region A1) including a plurality of wirings L in the vicinity of the first end E1 as in FIG. The cross-sectional view of FIG. 18 represents a cross section (cross section of the third region A3) including a plurality of wirings L and a plurality of pads P, as in FIG.

  As shown in FIG. 16, the substrate 2 in this embodiment includes a first layer 21, a second layer 22, and a third layer 23. The structure other than the substrate 2 is the same as the example of FIG. The first layer 21 has the above-described second surface F2. The second layer 22 is disposed between the first layer 21 and the wiring L, and has the first surface F1 described above. The third layer 23 is disposed between the first layer 21 and the second layer 22. The carbonized portion C is formed in the second layer 22. The first layer 21 and the second layer 22 can be formed of a resin material such as polyimide, polyester, or polycarbonate. The third layer 23 can be formed of an inorganic material, for example.

  As shown in FIG. 17, in the first region A1, the second layer 22 does not exist between the adjacent wirings L. Below the wiring L, the second layer 22 (carbonized portion C at the illustrated position) is disposed. Since the second layer 22 does not exist between the adjacent wirings L, the carbonized portions C below the wirings L are electrically independent from each other. As shown in FIG. 18, the second layer 22 does not exist between the adjacent pads P in the third region A3. A second layer 22 is disposed below the pad P.

Thus, in the present embodiment, the second layer 22 is removed in the same region as the region in which the thickness of the substrate 2 is reduced to the second thickness T2 in the first embodiment. As another example, the second layer 22 may be thinned in the same region as the region where the thickness of the substrate 2 is reduced to the second thickness T2 in the first embodiment. In this case, in the vicinity of the first end E1, the thickness of the second layer 22 between the adjacent wirings L is smaller than the thickness of the second layer 22 at the position of the wiring L.
Even with the configuration of the present embodiment, the same effects as those of the first embodiment can be obtained.

  The configurations related to the substrate 2, the resin layer 10, the wiring L, the pad P, the anisotropic conductive film ACF, and the connection member 4 disclosed in the first and second embodiments can be applied to other types of display devices as described above. . For example, for a liquid crystal display device that includes an array substrate, a counter substrate, and a liquid crystal layer disposed between the substrates, the configuration of each embodiment may be applied to the array substrate. The configuration of each embodiment may be applied.

As described above, all display devices that can be implemented by a person skilled in the art based on the display device described as the embodiment of the present invention are included in the scope of the present invention as long as they include the gist of the present invention.
In the scope of the idea of the present invention, those skilled in the art can conceive various modifications, and these modifications are also considered to be within the scope of the present invention. For example, those in which the person skilled in the art has appropriately added, deleted, or changed the design of the above-described embodiments, or those in which processes have been added, omitted, or changed conditions are also included in the present invention. As long as the gist is provided, it is included in the scope of the present invention.
Further, regarding other operational effects brought about by the aspects described in the respective embodiments, those that are apparent from the description of the present specification or that can be appropriately conceived by those skilled in the art are naturally understood to be brought about by the present invention. Is done.

  DESCRIPTION OF SYMBOLS 1 ... Display apparatus, 2 ... Board | substrate, 3 ... Optical film, 4 ... Connection member, 10 ... Insulating layer, E1 ... 1st edge part of board | substrate, DA ... Display area, PA ... Peripheral area, PX ... Pixel, TM ... Terminal , L ... wiring, P ... pad, ACF ... anisotropic conductive film, C ... carbonized portion, A1-A5 ... first to fifth regions.

Claims (10)

A substrate having a display area in which pixels are arranged, and a peripheral area around the display area;
A plurality of pads arranged in the peripheral region;
A plurality of wirings arranged in the peripheral region and electrically connected to each of the plurality of pads;
The wiring extends to an end of the substrate;
At the end, the thickness of the substrate at the position of the wiring is a first thickness, and the thickness of the substrate between the adjacent wirings is a second thickness smaller than the first thickness. is there,
Display device. The thickness of the substrate at the position of the pad is the first thickness, and the thickness of the substrate between adjacent pads is the second thickness,
The display device according to claim 1. The second thickness is 5 μm or less smaller than the first thickness,
The display device according to claim 1. An insulating layer covering the plurality of wirings;
In the end portion, the wiring is exposed from the insulating layer,
The display device according to claim 1. A connecting member facing the pad;
A conductive layer disposed between the connection member and the pad;
The insulating layer has an opening that exposes at least a part of the pad from the insulating layer;
The conductive layer electrically connects the pad and the connection member through the opening.
The display device according to claim 4. The insulating layer includes a portion having a third thickness between the pad and the display region,
A thickness of the insulating layer around the opening is a fourth thickness smaller than the third thickness;
The display device according to claim 5. In the periphery of the opening, the insulating layer is located between the conductive layer and the pad.
The display device according to claim 6. The insulating layer has a step between the pad and the display area,
The thickness of the insulating layer between the step and the display area is the third thickness, and the thickness of the insulating layer between the step and the pad is the fourth thickness.
The display device according to claim 6 or 7. The substrate is
The first layer;
A second layer disposed between the first layer and the plurality of wirings;
A third layer disposed between the first layer and the second layer,
The display device according to claim 1. At the end, the substrate includes a carbonized portion in contact with the wiring,
The display device according to claim 1.

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