Indicating device

Abstract

Provided is a display device with which it is possible to inhibit the leakage of scattered light to adjacent sub-pixels, the scattered light being formed when light leaked in the downward direction from a semiconductor light-emitting element in one sub-pixel is scattered at a joining part.　This display device comprises: a display panel that has a plurality of semiconductor light-emitting elements comprising light-emitting layers; a driver substrate that has a driver circuit and faces the display panel; and a plurality of joining parts that respectively electrically connect the plurality of semiconductor light-emitting elements to the driver substrate. If the direction in which the display panel and the driver substrate face each other is the line-of-sight direction, the center position of the light-emitting area of the semiconductor light-emitting element and the center position of the joining part joined to the semiconductor light-emitting element are offset from each other.

Description

Technical Field

[0001] The present disclosure relates to a display device, and more particularly to a display device having a plurality of semiconductor light-emitting elements.

Background Art

[0002] As a display device having a plurality of semiconductor light-emitting elements, there is proposed a device including a display panel having a plurality of semiconductor light-emitting elements forming sub-pixels, and a driving substrate having a driving circuit, and having a bump bonding portion as a bonding portion for electrically connecting each semiconductor light-emitting element and the driving substrate. Conventionally, as shown in Patent Document 1, the bump bonding portion is disposed directly below the semiconductor light-emitting element when the direction from the display panel to the driving substrate is defined as the downward direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technology of Patent Document 1, when light leaking downward from a semiconductor light-emitting element existing in one sub-pixel is scattered at the bump bonding portion, scattered light is formed. There is room for improvement in the technology of Patent Document 1 in terms of preventing the scattered light from leaking out toward an adjacent sub-pixel with respect to that sub-pixel.

[0005] The present disclosure has been made in view of the above points, and one of the objects is to provide a display device capable of suppressing scattered light formed when light leaking downward from a semiconductor light-emitting element of one sub-pixel is scattered at the bonding portion from leaking out to an adjacent sub-pixel.

Means for Solving the Problems

[0006] The present disclosure relates to, for example, a display panel having a plurality of semiconductor light-emitting elements each including a light-emitting layer, a driving substrate having a driving circuit and facing the display panel, and a plurality of bonding portions each electrically connecting one of the plurality of semiconductor light-emitting elements to the driving substrate. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the position of the center of the light-emitting region of the semiconductor light-emitting element and the position of the center of the bonding portion bonded to the semiconductor light-emitting element are displaced from each other. 、 A passage area is formed in a part of the light-emitting region through which light propagates toward the driving substrate. The joint portion has a side surface that is convexly curved, and an extended surface with a gentler slope than the side surface is formed between the end portion of the joint portion and the side surface. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the extended surface faces the passage area. The present disclosure relates to a display device.

Brief Description of the Drawings

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[0008] Hereinafter, an example and the like according to the present disclosure will be described with reference to the drawings. The description will be made in the following order. In this specification and the drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

[0009] Note that the description will be made in the following order. 1. First Embodiment 2. Second Embodiment 3. Third Embodiment

[0010] The following description is a preferred specific example of the present disclosure, and the content of the present disclosure is not limited to these embodiments and the like. In the following description, directions such as front and rear, left and right, and up and down are shown for convenience of explanation, but the content of the present disclosure is not limited to these directions. In examples such as FIGS. 1 and 2, the Z-axis direction is the up-down direction (the upper side is the +Z direction, and the lower side is the -Z direction), the X-axis direction is the front-rear direction (the front side is the +X direction, and the rear side is the -X direction), and the Y-axis direction is the left-right direction (the right side is the +Y direction, and the left side is the -Y direction), and the description will be made based on this. The same applies to FIGS. 3 to 27. The relative size ratios of the sizes and thicknesses of the respective layers shown in each of FIGS. 1 and the like are for convenience of description and do not limit the actual size ratios. The same applies to the definitions and size ratios regarding these directions for each of FIGS. 3 to 27.

[0011] [1 First Embodiment] [1-1 Configuration of Display Device] As shown in FIG. 1, the display device 1 according to the first embodiment includes a display panel 2 having a plurality of semiconductor light-emitting elements 3, a driving substrate 4 having a driving circuit, and a joint portion that electrically connects the semiconductor light-emitting element 3 and the driving substrate 4. FIG. 1 is a cross-sectional view showing an example of the configuration of the display device 1 according to the first embodiment. Note that, as will be described later, the joint portion of the display device 1 according to the first embodiment is a bump joint portion 5.

[0012] In addition, in FIG. 1 and the like, for convenience of explanation, the Z-axis is defined parallel to the direction in which the display panel 2 and the driving substrate 4 face each other (hereinafter sometimes simply referred to as the facing direction). The in-plane direction of the two-dimensional plane defined by the X-axis and the Y-axis coincides with the in-plane direction of the main surface of the display panel 2. In the examples of FIGS. 1 and 2, the semiconductor light-emitting elements 3 are arranged in a matrix, and the X-axis and the Y-axis are defined along the arrangement direction of the semiconductor light-emitting elements 3. FIG. 2 is a schematic plan view showing the arrangement of the semiconductor light-emitting elements 3 of the display device 1 in the example of FIG. 1. In FIG. 2, for convenience of explanation, the arrangement of the light-emitting layer 12, the light-emitting layer 12 in the -Z direction, the second compound semiconductor layer 11, the second electrode 9, and the joint portion (bump joint portion 5) is illustrated, and the description of other layers and the like is omitted. This also applies to the schematic plan views showing the arrangement of the semiconductor light-emitting elements 3 of the display device 1 described in FIGS. 5 to 11, FIG. 16, and FIGS. 18 to 23. In FIG. 2, the description of the seed layer 15 is also omitted. This also applies to FIGS. 3 to 27. Note that when the direction in which the display panel 2 and the driving substrate 4 face each other is defined as the line-of-sight direction, in the example of FIG. 1, it indicates the case where the direction along the Z-axis is defined as the line-of-sight direction. In the display device 1, the direction from the driving substrate 4 toward the display panel 2 (+Z direction) is defined as the upward direction along the normal direction (Z-axis) of the unit region R, which will be described later, and the upward direction from the display panel 2 toward the driving substrate 4 is defined as the downward direction (-Z direction).

[0013] (Display panel) The display panel 2 has a plurality of semiconductor light-emitting elements 3. In the display panel 2, an image display area is defined in a predetermined area thereof. In the image display area, a large number of pixels formed from sub-pixels are usually formed in a predetermined arrangement pattern. In the example of FIG. 2, a large number of pixels formed from three types of sub-pixels with different colors are formed in a matrix. For example, in the example of FIG. 2, combinations of three types of sub-pixels are arranged along the X-axis direction, and sub-pixels of the same color may be arranged in columns along the Y-axis direction. One semiconductor light-emitting element 3 corresponds to one sub-pixel. In examples such as FIGS. 1 and 2, a laminated structure 7 described later that constitutes the semiconductor light-emitting element 3 is formed for each sub-pixel, and a group of a plurality of laminated structures 7 is formed in the image display area.

[0014] (Semiconductor light-emitting element) In the example of FIG. 1, the semiconductor light-emitting element 3 includes an element substrate 6, a compound semiconductor laminated structure (hereinafter simply referred to as "laminated structure") 7, a first electrode 8, and a second electrode 9.

[0015] (Element substrate) The element substrate 6 supports the laminated structure 7. The element substrate 6 has a first main surface on the side of the laminated structure 7 and a second main surface on the opposite side thereof. The element substrate 6 is, for example, a GaAs substrate, a GaN substrate, a SiC substrate, an alumina substrate, a sapphire substrate, a ZnS substrate, a ZnO substrate, an AlN substrate, a LiMgO substrate, a LiGaO2 substrate, a MgAl2O4 substrate, an InP substrate, a Si substrate, a Ge substrate, a GaP substrate, an AlP substrate, an InN substrate, an AlGaInN substrate, an AlGaN substrate, an AlInN substrate, a GaInN substrate, an AlGaInP substrate, an AlGaP substrate, an AlInP substrate, or a GaInP substrate. An underlayer, a buffer layer, or the like may be provided on the first main surface of the element substrate 6.

[0016] (Laminated structure) The laminated structure 7 is provided on the first main surface of the element substrate 6. The laminated structure 7 has a first main surface 71 on the side opposite to the element substrate 6 and a second main surface 72 on the side of the element substrate 6.

[0017] The stacked structure 7 includes a plurality of stacked compound semiconductor layers. Specifically, the stacked structure 7 includes a first compound semiconductor layer 10, a second compound semiconductor layer 11, and a light-emitting layer 12. The light-emitting layer 12 is provided between the first compound semiconductor layer 10 and the second compound semiconductor layer 11. However, the configuration of the stacked structure 7 is not limited to this, and it may have a stacked structure other than the above.

[0018] The first compound semiconductor layer 10 has a first main surface on the light-emitting layer 12 side and a second main surface on the side opposite to the light-emitting layer 12 side.

[0019] The first compound semiconductor layer 10 has a first conductivity type, and the second compound semiconductor layer 11 has a second conductivity type that is opposite to the first conductivity type. Specifically, the first compound semiconductor layer 10 has an n-type, and the second compound semiconductor layer 11 has a p-type.

[0020] The first compound semiconductor layer 10 and the second compound semiconductor layer 11 contain a compound semiconductor. The compound semiconductor is, for example, a GaN-based compound semiconductor (including AlGaN mixed crystal, AlInGaN mixed crystal, or InGaN mixed crystal), an InN-based compound semiconductor, an InP-based compound semiconductor, an AlN-based compound semiconductor, a GaAs-based compound semiconductor, an AlGaAs-based compound semiconductor, an AlGaInP-based compound semiconductor, an AlGaInAs-based compound semiconductor, an AlAs-based compound semiconductor, a GaInAs-based compound semiconductor, a GaInAsP-based compound semiconductor, a GaP-based compound semiconductor, or a GaInP-based compound semiconductor.

[0021] The n-type impurity added to the first compound semiconductor layer 10 is, for example, silicon (Si), selenium (Se), germanium (Ge), tin (Sn), carbon (C), or titanium (Ti). The p-type impurity added to the second compound semiconductor layer 11 is zinc (Zn), magnesium (Mg), beryllium (Be), cadmium (Cd), calcium (Ca), barium (Ba), or oxygen (O).

[0022] The light-emitting layer 12 contains a compound semiconductor. Examples of the compound semiconductor include the same materials as those of the first compound semiconductor layer 10 and the second compound semiconductor layer 11. The light-emitting layer 12 may be composed of a single compound semiconductor layer, or may have a single quantum well structure (SQW structure) or a multiple quantum well structure (MQW structure).

[0023] (First electrode) The display panel 2 is provided with a first electrode 8. In the example of FIG. 1, the first electrode 8 is disposed on the surface region (the first main surface side) of the first compound semiconductor layer 10 so as to surround the group of the plurality of stacked structures 7, and is electrically connected to the first compound semiconductor layer 10. The first electrode 8 is connected to the first compound semiconductor layer 10 common to all of the plurality of stacked structures 7. The first electrode 8 functions as a common electrode in the plurality of semiconductor light-emitting elements 3.

[0024] Examples of the material of the first electrode 8 include indium oxide, indium-tin oxide (ITO: Indium Tin Oxide, including Sn-doped In2O3, crystalline ITO, and amorphous ITO), indium-zinc oxide (IZO: Indium Zinc Oxide), indium-gallium oxide (IGO), indium-doped gallium-zinc oxide (IGZO, In-GaZnO4), IFO (F-doped In2O3), tin oxide (SnO2), ATO (Sb-doped SnO2), FTO (F-doped SnO2), zinc oxide (ZnO, including Al-doped ZnO, B-doped ZnO, and Ga-doped ZnO), antimony oxide, spinel-type oxide, or oxide having a YbFe2O4 structure. The first electrode 8 may be a transparent conductive layer having a gallium oxide, titanium oxide, niobium oxide, nickel oxide, or the like as a mother layer.

[0025] The first electrode 8 may contain at least one metal selected from the group consisting of, for example, palladium (Pd), platinum (Pt), nickel (Ni), Al (aluminum), Ti (titanium), gold (Au), and silver (Ag).

[0026] The first electrode 8 may have a single-layer structure or a multilayer structure (for example, Ti / Pt / Au).

[0027] (The second electrode) The second electrodes 9 are individually and electrically connected to the second compound semiconductor layers 11 of the respective stacked structures 7. In the examples of FIGS. 1 and 2, the second electrodes 9 extend in the -X direction from directly below the second compound semiconductor layers 11 toward the insulating layer 14 described later. By forming the second electrodes 9 to extend to a position away from directly below the second compound semiconductor layers 11, even if a seed layer 15 described later is omitted, it becomes easy to form the bump bonding portions 5 at positions deviated from the center C of the unit region R. R

[0028] Also, in a part of the region on the lower side (-Z direction side) of the stacked structure 7, there is a non-formation portion of the second electrode 9. This non-formation portion forms a non-formation portion 13 of the laminate of the second electrode 9, the seed layer 15, and the inorganic film 16 as described later, and the second electrodes 9 are separated between adjacent semiconductor light-emitting elements 3 by the non-formation portion 13.

[0029] The second electrode 9 may be formed in the same shape as the seed layer 15 described later, or may be formed in a shape different from the seed layer 15. Forming the second electrode 9 and the seed layer 15 in the same shape is preferable from the viewpoint of reducing the number of manufacturing steps of the display device in that the formation steps of the second electrode 9 and the seed layer 15 can be combined.

[0030] Examples of the second electrode 9 include at least one metal (including alloys) selected from the group consisting of gold (Au), silver (Ag), palladium (Pd), platinum (Pt), nickel (Ni), Al (aluminum), Ti (titanium), tungsten (W), vanadium (V), chromium (Cr), Cu (copper), zinc (Zn), tin (Sn), and indium (In).

[0031] The second electrode 9 may have a single-layer structure or a multi-layer structure. Examples of the multi-layer structure include Ti / Au, Ti / Al, Ti / Pt / Au, Ti / Al / Au, Ni / Au, AuGe / Ni / Au, Ni / Au / Pt, Ni / Pt, Pd / Pt, or Ag / Pd. In the multi-layer structure, the layer before " / " is located closer to the light-emitting layer 12. The same applies to the following description.

[0032] (Insulating layer) An insulating layer 14 is formed between adjacent stacked structures 7 on the element substrate 6. The insulating layer 14 separates the adjacent stacked structures 7. The insulating layer 14 has a plurality of openings 14A, and the second compound semiconductor layer 11 of the separated stacked structure 7 is exposed from the openings 14A. As shown in the example of FIG. 1, the insulating layer 14 may cover a portion from the peripheral edge of the first surface of the second compound semiconductor layer 11 to the side surface (end face). In this specification, the peripheral edge of the first surface refers to a region having a predetermined width inward from the peripheral edge of the first surface.

[0033] Examples of the insulating layer 14 include a layer containing a SiO X -based material, a SiN Y -based material, a SiO X N Y -based material, Ta2O5, ZrO2, AlN, or Al2O3.

[0034] (Arrangement and Shape of Semiconductor Light-Emitting Element) As shown in the examples of FIGS. 1 and 2, in the display device 1, a plurality of stacked structures 7 are arranged on the element substrate 6, thereby forming a group of a plurality of semiconductor light-emitting elements 3 on the display panel 2. Further, when the direction in which the display panel 2 and the driving substrate 4 face each other is taken as the line-of-sight direction, the plurality of semiconductor light-emitting elements 3 are two-dimensionally arranged. The arrangement pattern of the plurality of semiconductor light-emitting elements 3 is determined according to the pattern of sub-pixels. In the example of FIG. 2, when the Z-axis direction is taken as the line-of-sight direction, the plurality of semiconductor light-emitting elements 3 are arranged in a matrix in the X-axis direction and the Y-axis direction. The shape of the semiconductor light-emitting element 3, similar to the arrangement of the semiconductor light-emitting element 3, is determined according to the pixels and sub-pixels of the display device 1. Examples of the shape of the semiconductor light-emitting element 3 can include a circular shape, a hexagonal shape, a rectangular shape (square, rectangle), etc. In the example of FIG. 2, when the Z-axis direction is taken as the line-of-sight direction, the shape of the semiconductor light-emitting element 3 is formed in a rectangular shape.

[0035] (Emission color) The emission colors of the plurality of semiconductor light-emitting elements 3 may be one type or two or more types. For example, the emission colors of the semiconductor light-emitting elements 3 may be three types: red, green, and blue. In the case of the example of FIG. 2, in the X-axis direction, semiconductor light-emitting elements with emission colors of red, green, and blue (red semiconductor light-emitting elements, green semiconductor light-emitting elements, blue semiconductor light-emitting elements) may be repeatedly arranged, and in the Y-axis direction, semiconductor light-emitting elements with the same emission color may be arranged. In the case of this example, the emission colors of the semiconductor light-emitting elements are three types, the emission colors of the semiconductor light-emitting elements adjacent to each other in the X-axis direction are different from each other, and the emission colors of the semiconductor light-emitting elements adjacent to each other in the Y-axis direction are the same. Since each semiconductor light-emitting element is arranged in an individual sub-pixel, in that example, one pixel may be formed by three sub-pixels formed by three types of semiconductor light-emitting elements arranged in the X-axis direction.

[0036] (Emission region (unit region) of each semiconductor light-emitting element) In the display device 1, when the Z-axis direction is taken as the line-of-sight direction, an emission region is specified individually for each semiconductor light-emitting element 3. In this specification, this specified emission region is referred to as a unit region R.

[0037] The light-emitting region defined for the semiconductor light-emitting element 3 described above indicates the light-emitting region of the light-emitting layer 12 (the region recognized on the XY plane) when the Z-axis direction is the line-of-sight direction.

[0038] In the examples of FIGS. 1 and 2, the entire formation region of the light-emitting layer 12 is the light-emitting region, that is, the existing region of the light-emitting layer 12 recognized when the Z-axis direction is the line-of-sight direction is the unit region R. Note that this also applies to FIGS. 3 to 27. That is, in this specification, the description using FIGS. 1 to 27 will be continued, where the unit region R is the light-emitting region of the light-emitting layer 12.

[0039] In the display device 1, as shown in FIG. 2 and the like, adjacent unit regions R are separated, and a plurality of unit regions R are two-dimensionally arranged. The arrangement pattern of the unit regions R and the shape of each individual unit region are determined according to the arrangement pattern and shape of the semiconductor light-emitting elements 3. In the examples of FIGS. 1 and 2, the arrangement of the unit regions R is formed in a matrix, and the shape of the unit region R is rectangular. The arrangement direction of the unit regions R is the X-axis direction and the Y-axis direction.

[0040] The center of the unit region R indicates the geometric center of the unit region R, and in the examples of FIGS. 1 and 2, it is denoted by the reference sign C R For example, when the shape of the unit region R is approximately rectangular, the center C R of the unit region R is located at or near the intersection of the two diagonals defined for the rectangle. When the shape of the unit region R is approximately a regular polygon, the center C R of the unit region R is located at approximately the center of the circumscribed circle of the regular polygon. When the shape of the unit region R is approximately circular, the center C R of the unit region R is located at approximately the center of the circle. When the shape of the unit region R is approximately elliptical, the center C R of the unit region R is located at or near the intersection of the major axis and the minor axis of the ellipse. These also apply to FIGS. 2 to 27.

[0041] (Seed layer) As shown in FIG. 1, it is preferable that the display panel 2 is provided with a seed layer 15 for each semiconductor light-emitting element 3 to enhance the bondability of the bump joint 5 described later to the display panel 2. The seed layer 15 is electrically connected to both the bump joint 5 and the second electrode 9. The seed layer 15 shown in FIG. 1 is formed in a region extending from directly below the laminated structure 7 onto the insulating layer 14. Thereby, it becomes easy to arrange the bump joint 5 at a position shifted from the center C of the unit region R. For convenience of explanation, the description of the seed layer 15 is omitted in FIGS. 2 to 27. R This makes it easy to arrange the bump joint 5 at a position shifted from the center C of the unit region R. For convenience of explanation, the description of the seed layer 15 is omitted in FIGS. 2 to 27.

[0042] The arrangement pattern of the seed layer 15 is preferably the same as that of the second electrode 9 as described above. When formed in the same arrangement pattern as the second electrode 9, the processes of forming the second electrode 9 and the seed layer 15 can be merged, and the manufacturing cost can be reduced as described above. Also, a non-formed portion is formed in the seed layer 15 according to the formation position of the non-formed portion of the second electrode 9.

[0043] From the viewpoint of improving the adhesion between the semiconductor light-emitting element 3 and the bump joint 5, the material of the seed layer 15 preferably has an affinity with the material forming the bump joint 5. Also, the material of the seed layer 15 is preferably a conductive metal that hardly forms an alloy with the material forming the bump joint 5. Examples of such a material include metals such as nickel (Ni). In this case, the seed layer 15 can also function as a barrier metal layer that suppresses the diffusion of the material forming the bump joint 5 from one connection end 5A of the bump joint 5 to the semiconductor light-emitting element 3 side.

[0044] (Inorganic film) In the display panel 2, an inorganic film 16 may be formed in a region excluding the facing region with the bump joint 5 on the connection surface with the bump joint 5 on the first main surface side. By forming the inorganic film 16, the second electrode 9 and the seed layer 15 can be protected. A non-formed portion is also formed in the inorganic film 16 according to the formation position of the non-formed portion of the second electrode 9.

[0045] (Non-formation portion 13) In the example shown in FIG. 1, a non-formation portion 13 of a laminate of a second electrode 9, a seed layer 15, and an inorganic film 16 is formed on the formation surface side of the laminate 7 of the element substrate 6. The non-formation portion 13 is formed according to the formation pattern of the second electrode. By the non-formation portion 13, the second electrode 9, the seed layer 15, and the inorganic film 16 are separated for each semiconductor light-emitting element 3. Further, a through-region Q is formed by the formation of the non-formation portion 13 as will be described later.

[0046] (Through-region) In the display device 1, a through-region Q is formed. The through-region Q is formed in a region overlapping with the non-formation portion 13 of the laminate of the second electrode 9, the seed layer 15, and the inorganic film 16 and the unit region R. The light generated from the light-emitting layer 12 of the laminate 7 may exit downward (-Z direction) from the driving substrate 4 side as leakage light L1 through the through-region Q formed in the non-formation portion 13 as shown in FIG. 1.

[0047] (Example of semiconductor light-emitting element) Examples of the semiconductor light-emitting element 3 include a micro LED (Light Emitting Diode). In the micro LED, the light-emitting layer 12 of the above-described laminate 7 is formed with very fine dimensions such as dimensions of micrometers or less. By the semiconductor light-emitting element 3 being a micro LED, a display device with high definition and excellent contrast can be obtained.

[0048] (Driving substrate) The driving substrate 4 includes a substrate 17 on which a driving circuit is formed. As the material of the substrate 17, the same material as that of the element substrate 6 can be used. Examples of the driving circuit include a logic circuit. The driving circuit forms, for example, a circuit for controlling the driving of each semiconductor light-emitting element 3.

[0049] On the surface of the driving substrate 4, a pad portion (not shown) is formed on the side facing the semiconductor light-emitting element 3. The pad portion serves as a connection terminal for electrically connecting the semiconductor light-emitting element 3 and the driving circuit, and is provided individually with respect to the bonding portion (bump bonding portion 5). Each pad portion is electrically connected to the corresponding semiconductor light-emitting element 3 via the bump bonding portion 5. It is preferable that a seed layer 18 for enhancing the adhesiveness of the bump bonding portion 5 to the driving substrate 4 is formed on the pad portion of the driving substrate 4, similarly to the semiconductor light-emitting element 3. The seed layer 18 formed on the driving substrate 4 may be made of the same material as the seed layer 15 formed on the display panel 2 side corresponding to each bonding portion.

[0050] (Bonding portion) Each semiconductor light-emitting element 3 is individually electrically connected to the driving substrate 4 via a bonding portion. In the example of the display device 1 in FIG. 1, the bonding portion for electrically connecting each of the semiconductor light-emitting elements 3 and the driving substrate 4 is formed by the bump bonding portion 5. The bump bonding portion 5 is a bonding portion between the bump 26 individually arranged on the semiconductor light-emitting element 3 of the display panel 2 and the bump 27 arranged on the driving substrate 4.

[0051] (Type and material of bumps) The bumps 26 and 27 forming the bump bonding portion 5 are not particularly limited, and examples thereof include pillar bumps, stud bumps, etc. Examples of the materials of the bumps 26 and 27 include solder, nickel, gold, silver, copper, tin, etc., and alloys thereof. From the viewpoint that the formation of the bump bonding portion can be easily performed, it is preferable to use a material having reflowability by heat for the materials of the bumps 26 and 27. Examples of the material having reflowability by heat include solder and materials constituting solder.

[0052] (Position of the bonding portion) When the direction in which the display panel 2 and the driving substrate 4 face each other (Z-axis direction) is taken as the line-of-sight direction, the center C of the unit region R which is the center of the light-emitting region of the semiconductor light-emitting element 3 RThe position of [the relevant part] and the position of the center of the bump joint portion 5 joined to the semiconductor light-emitting element 3 are shifted from each other. Here, the center of the bump joint portion 5 means the center of the element joint region J described later.

[0053] (Element joint region and substrate joint region) As shown in FIG. 1, in the bump joint portion 5 which is a joint portion, an element joint region J joined to the semiconductor light-emitting element 3 is formed at one end thereof (the end in the +Z direction) (one connection end 5A side), and a substrate joint region K joined to the drive substrate 4 is formed at the other end thereof (the end in the -Z direction) (the other connection end 5B side). In FIG. 1, the symbol C J indicates the center of the element joint region J, and the symbol C K indicates the center of the substrate joint region K. The element joint region J indicates a region recognized on the XY plane when the joint region between the bump joint portion 5 and the semiconductor light-emitting element 3 is viewed with the Z-axis direction as the line-of-sight direction. The substrate joint region K indicates a region recognized on the XY plane when the joint region between the bump joint portion 5 and the drive substrate 4 is viewed with the Z-axis direction as the line-of-sight direction.

[0054] (Formation position of element joint region) In the display device 1, as described above, the position of the center C R of the unit region R and the position of the center of the bump joint portion 5 are shifted from each other. That is, when the direction in which the display panel 2 and the drive substrate 4 face each other (the Z-axis direction) is taken as the line-of-sight direction, the position of the center C R of the unit region R and the position of the center C J of the element joint region J formed in the joint portion (bump joint portion 5) joined to the semiconductor light-emitting element 3 corresponding to that unit region R are shifted from each other. The center C J of the element joint region J indicates the geometric center of the element joint region J, similar to the center C R of the unit region R. In the example of FIG. 1, the element joint region J is substantially circular, and the center C J of the element joint region J is the center of the circle. Note that the center C K of the substrate joint region K indicates the geometric center of the substrate joint region K, similar to the center C R of the unit region R.

[0055] Therefore, as shown in FIG. 1 and the like, the center C of the unit region R R and the center C of the element bonding region J J being displaced from each other indicates that the position of the geometric center of the element bonding region J is displaced from the geometric center of the unit region R.

[0056] In the display device 1, as shown in FIG. 1, the center C of the element bonding region J J is arranged at a position displaced from the center C of the unit region R R so that scattered light L2 formed when leakage light L1 traveling downward from the through region Q formed in the non-formation portion 13 in the semiconductor light-emitting element 3 is scattered by the bump bonding portion 5 can be effectively suppressed from entering an adjacent sub-pixel.

[0057] (Amount of displacement) As shown in FIG. 1, the magnitude of the displacement (amount of displacement M) between the center C of the element bonding region J J and the center C of the unit region R R is preferably 1 / 4 or more and 3 / 4 or less of the center-to-center distance D of adjacent unit regions R along the direction of the displacement. The direction of the displacement is along the straight line connecting the center C of the element bonding region J J and the center C of the unit region R R In the example of FIG. 1, the direction of the displacement is along the arrangement direction of the semiconductor light-emitting elements 3 and is along the X-axis direction.

[0058] In the display device 1, when the misalignment amount M is 1 / 4 or more and 3 / 4 or less of the center - to - center distance D of adjacent unit regions R along the misalignment direction, the scattered light L2 can be more effectively suppressed from entering the regions of adjacent sub - pixels. In particular, when the emission colors of adjacent sub - pixels are different along the misalignment direction, color mixing between the colors of adjacent sub - pixels and the color of the scattered light L2 can be avoided. From the viewpoint of enhancing such an effect, the misalignment amount M is more preferably about 1 / 2 of the center - to - center distance D of adjacent unit regions R along the misalignment direction, and even more preferably is 1 / 2 of the center - to - center distance D of adjacent unit regions R along the misalignment direction.

[0059] (Size of the element bonding region) As shown in FIG. 1, when adjacent unit regions R are separated, from the viewpoint of suppressing the generation of scattered light L2, it is preferable that the element bonding region J is located within the region W between adjacent unit regions R when the direction in which the display panel and the driving substrate face each other is taken as the viewing direction.

[0060] (Side - face shape of the bump bonding portion) The bump bonding portion 5 has a shape having a portion extending outward (in the XY - plane direction) from the element bonding region J. In the example of FIG. 1, the side - face portion 19 of the bump bonding portion 5 forms a convexly - curved surface. Note that the entire side - face portion 19 of the bump bonding portion 5 may be convexly curved, or a part thereof may be convexly curved. In the example of FIG. 1, the curved surface formed on the side - face portion 19 is convexly curved so as to form a convex end 20 at a position between one end (connection end 5A) and the other end (connection end 5B) of the bump bonding portion 5.

[0061] Regarding the position of the side - face portion 19 of the bump bonding portion 5, when the direction in which the display panel 2 and the driving substrate 4 face each other is taken as the viewing direction, it is preferable that the position of the side - face portion 19 of the bump bonding portion 5 is determined such that the convex end 20 of the convexly - curved side - face portion 19 is arranged at a position avoiding the passing region Q as described above.

[0062] (Underfill layer) An underfill material is filled in a gap space 24 formed between a display panel 2 and a driving substrate 4 connected via bump joints 5. An underfill layer 21 is formed of the underfill material filled in the gap space 24. As the underfill material, a thermosetting resin or the like can be used.

[0063] (Effect) In the display device 1 according to the first embodiment, the center C of the element bonding region J J is deviated from the center C of the unit region R R so that the bump joints 5 are arranged. Therefore, when the leakage light L1 propagating downward from the light emitting layer 12 through the through-hole region Q formed in the non-formation portion 13 is scattered by the bump joints 5 to form scattered light L2, the scattered light L2 is returned to the light emitting layer 12 side of the semiconductor light emitting element 3 that is the propagation source of the leakage light L1, and it becomes difficult for the scattered light L2 to go in the direction of the semiconductor light emitting element 3 of an adjacent sub-pixel. For this reason, in the display device 1, it is possible to suppress the scattered light from entering the area of an adjacent sub-pixel.

[0064] Also, in the display device 1 according to the first embodiment, since the scattered light L2 is returned to the light emitting layer 12 side of the semiconductor light emitting element 3 that is the propagation source of the leakage light L1, it is possible to obtain a display device with improved light utilization efficiency and excellent luminance.

[0065] [1-2 Modification Example] [Modification Example 1] (Position of the Side Surface Portion of the Bump Joint) Regarding the position of the side surface portion 19 of the bump joint 5, as shown in FIGS. 3 and 4, when the direction in which the display panel 2 and the driving substrate 4 face each other is taken as the line-of-sight direction, not only the convex end 20 of the convexly curved side surface portion 19 but also the entire side surface portion 19 may be positioned so as not to overlap the through-hole region Q as described above. This can be realized by specifying the size and position of the bump joint 5.

[0066] For example, as shown in FIG. 3, the size V of the bump joint portion 5 may be set to a size such that when the direction in which the display panel 2 and the driving substrate 4 face each other is the line-of-sight direction, the bump joint portion 5 is accommodated within the region W between adjacent unit regions. At this time, in the bump joint portion 5, the element bonding region J is also formed so as to be located in the region W between adjacent unit regions. In this case, when the direction in which the display panel 2 and the driving substrate 4 face each other is the line-of-sight direction, the entire bump joint portion 5 can be positioned within the region W between adjacent unit regions, and the side surface portion 19 of the bump joint portion 5 is arranged at a position avoiding the passing-through region Q. For this reason, it is possible to suppress the leakage light L1 from the passing-through region Q from being scattered by the side surface portion 19 of the bump joint portion 5, and it is possible to suppress the scattered light L2 from entering the adjacent sub-pixels.

[0067] As shown in FIG. 4, the size of the bump joint portion 5 may be set such that the convexly curved side surface portion 19 is arranged at a position closer to the center of the unit region R than the passing-through region Q. For example, in the example of FIG. 4, between the end portion of the bump joint portion 5 and the side surface portion 19, that is, between the edge portion of the element bonding region J at the connection end 5A along the outer peripheral surface of the bump joint portion 5 and the side surface portion 19, an extended surface 22 extending in the plane direction (XY plane direction) with the Z-axis direction as the normal direction is formed, and the extended surface 22 is formed with a gentler inclination than the side surface portion 19. And when the direction in which the display panel 2 and the driving substrate 4 face each other is the line-of-sight direction, the extended surface 22 faces the passing-through region Q. In this case, the light propagating from the semiconductor light-emitting element 3 to the driving substrate 4 side through the passing-through region Q is easily reflected by the extended surface 22 of the bump joint portion 5 and returned to the original passing-through region Q as it is.

[0068] [Modification Example 2] (Modification Example of the Deviation Direction of the Center of the Element Bonding Region) In the display device 1 shown in the example of FIG. 1, the bump joint portion 5 is at the center C of the unit region R Ris provided at a position shifted in the X-axis direction, that is, the direction of the displacement of the element bonding region J is along the X-axis direction. In the display device 1, the direction of the displacement of the element bonding region J is not limited to the X-axis direction, and may be, for example, the Y-axis direction, or may be a direction obliquely intersecting the X-axis within the plane spanned by the X-axis and the X-axis as shown in FIG. 5 (the direction of arrow P in FIG. 5). Also, the center C of the element bonding region J J The amount of displacement M in the P direction is preferably in the range of 1 / 4 or more and 3 / 4 or less of the center-to-center distance D of the unit regions R adjacent in the P direction, and more preferably approximately 1 / 2 of the center-to-center distance D of the unit regions R adjacent in the P direction. This also applies to Modifications 3 to 6 described later.

[0069] [Modification 3] (Modification of the shape of the bump connection portion) Also, in the example of FIG. 1, when the Z-axis direction is the line-of-sight direction, the outer contour shape of the bump bonding portion 5 is a circle, but it is not limited to this. The outer contour shape of the bump bonding portion 5 may be formed, for example, in an elliptical shape as shown in FIG. 6, or may be formed in a rectangular shape as shown in FIG. 7.

[0070] Note that in the example of FIG. 6, the outer contour shape of the bump bonding portion 5 when the Z-axis direction is the line-of-sight direction is an ellipse, and an example where the element bonding region J is circular is illustrated. In the display device 1, the element bonding region J may be elliptical.

[0071] In the example of FIG. 7, the outer contour shape of the bump bonding portion 5 when the Z-axis direction is the line-of-sight direction is a rectangle, and an example where the element bonding region J is rectangular is illustrated. The center C of the element bonding region J in this case J is the intersection position of the two diagonals in the rectangle. Note that FIG. 7 also corresponds to Modification 1 described above. That is, in the example of FIG. 7, the element bonding region J is arranged in the region W between the adjacent unit regions R, and the side surface portion 19 of the bump bonding portion 5 is also located in the region W between the adjacent unit regions.

[0072] [Modification 4] In the description of the display device 1 according to the first embodiment and in Modification 3, the displacement direction of the element bonding region J of the bump bonding portion 5 was in one direction. However, the present invention is not limited to this example. For example, as shown in FIG. 8, a bump bonding portion 5 having the X-axis direction as the displacement direction of the element bonding region J and a bump bonding portion 5 having the Y-axis direction as the displacement direction of the element bonding region J may be connected to the second electrode 9 of one semiconductor light-emitting element 3. In the example of FIG. 9, for both the bump bonding portion 5 having the X-axis direction as the displacement direction and the bump bonding portion 5 having the Y-axis direction as the displacement direction, the outer contour shape of the bump bonding portion 5 when the Z-axis direction is the line-of-sight direction is rectangular, and the case where the element bonding region J is rectangular is illustrated.

[0073] [Modification 5] In the example of the display device 1 shown in the above Modification 4, the element bonding region J of the bump bonding portion 5 having the X-axis direction as the displacement direction and the element bonding region J of the bump bonding portion 5 having the Y-axis direction as the displacement direction were provided in a separated state. However, as shown in FIG. 9, the element bonding region J of the bump bonding portion 5 having the X-axis direction as the displacement direction and the element bonding region J of the bump bonding portion 5 having the Y-axis direction as the displacement direction may be connected to each other. This can be realized, for example, by forming a shape in which the longitudinal end (-Y direction end) of the bump bonding portion 5 in the X-axis displacement direction and the longitudinal end (-X direction end) of the bump bonding portion 5 in the Y-axis displacement direction in the example of FIG. 8 are connected to each other. In the display device 1 shown in FIG. 9, the bump bonding portion 5 is formed in an L-shaped as a whole and is disposed around the semiconductor light-emitting element 3. Note that the bump bonding portion 5 is not limited to an L-shape, and may be formed in a U-shape or an annular shape and disposed around the semiconductor light-emitting element.

[0074] As shown in the above Modifications 2 to 5, in the display device 1, when the Z-axis direction is the line-of-sight direction, the shape of the bump bonding portion 5 and the element bonding region J may be a shape selected from the group consisting of a circular shape, an elliptical shape, a rectangular shape, and an L-shaped.

[0075] [Modification 6] (Honeycomb arrangement) In the example of the display device 1 shown in FIG. 1, although the individual unit regions R were formed in a rectangular shape and the unit regions R were arranged in a matrix, the shape and arrangement of the unit regions R are not limited to this. As shown in FIGS. 10 and 11, the individual unit regions R may be formed in a hexagonal shape and these unit regions R may be arranged in a honeycomb pattern.

[0076] In the example of the display device 1 shown in FIG. 10, the S1 axis, S2 axis, and S3 axis are defined in the in-plane direction of the unit region R. The S1 axis, S2 axis, and S3 axis are arranged at positions rotated clockwise with reference to the center C R of the unit region R. The S2 axis is an axis rotated 60° with respect to the S1 axis. The S3 axis is an axis rotated 60° with respect to the S2 axis. Also, the S1 axis, S2 axis, and S3 axis are in a state of being defined in the direction in which the sides forming adjacent unit regions R face each other.

[0077] In the display device 1 of FIG. 10, the centers C of the element bonding regions J of the bump bonding portion 5 as an example of the bonding portion J are formed in plural, and the centers C of the respective element bonding regions J J are formed at positions shifted in the axial directions of the S1 axis, S2 axis, and S3 axis respectively from the center C R of the unit region R.

[0078] When the unit regions R are arranged in a honeycomb pattern, the center C of the element bonding region J of the bump bonding portion 5 J may be formed such that the direction of displacement is a direction that obliquely intersects any of the axial directions of the S1 axis, S2 axis, and S3 axis. For example, as shown in FIG. 11, the element bonding region J of the bump bonding portion 5 may be formed at a position between three unit regions R arranged in a delta shape. In the display device shown in FIG. 11, the center C of the element bonding region J R is formed at a position shifted in the S4 axis direction from the center C J of the unit region R. The S4 axis is in the in-plane direction of the unit region R and is defined in a direction passing through the vertex portion of the unit region R and perpendicular to the S2 axis.

[0079] Even when the unit regions R are arranged in a honeycomb pattern, when the Z-axis direction is the line-of-sight direction, the outer contour shapes of the element bonding region J and the bump bonding portion 5 are not particularly limited, but in the example of FIG. 10, they are formed in a rectangular shape, and in the example of FIG. 11, they are formed in a triangular shape.

[0080] [1-3 Manufacturing method of display device] Next, in the case where the display device is a display device according to the first embodiment, the manufacturing method of the display device is exemplified as shown in FIGS. 12 to 14.

[0081] Prepare an element substrate, and on the first main surface of the element substrate 6, a first compound semiconductor layer 10, a light-emitting layer 12, and a second compound semiconductor layer 11 are patterned in this order (FIG. 12A), and a first electrode is formed at a predetermined position on the first compound semiconductor layer. At this time, a stacked structure 7 is formed. The formation and stacking of the second compound semiconductor layer 11, the light-emitting layer 12, and the first compound semiconductor layer 10 can be carried out using a combination of a crystal growth method, a lithography method, a dry etching method, and a wet etching method. As the crystal growth method, the lithography method, the dry etching method, and the wet etching method, well-known techniques may be used respectively.

[0082] Next, as shown in FIG. 12B, an insulating film 140 is formed to cover the surface of the first compound semiconductor layer 10 and the stacked structure 7. A portion of the insulating film 140 formed in a predetermined region on the first main surface 71 of the stacked structure 7 is removed. At this time, an opening 14A is formed in the removed portion. In the opening 14A, the first main surface 71 of the stacked structure 7 is exposed (FIG. 12C). Also, the remaining portion of the insulating film 140 forms the insulating layer 14. Next, a second electrode 9 and a seed layer (not shown) are laminated in this order so as to cover the insulating layer 14 and the first main surface 71 of the stacked structure 7 (FIG. 12D), and further, an inorganic film 16 is laminated (FIG. 12E). A resist 25 is disposed on the surface of the inorganic film 16, and the inorganic film 16 is patterned using a lithography method or the like to expose the seed layer (in the drawing, it is a view in which the second electrode is exposed) (inorganic film forming step). After the inorganic film forming step, plating is further performed on the exposed portion of the seed layer (plating step), and a columnar body 23 is formed on the second electrode 9 or the seed layer (FIG. 13A). The plating is composed of a material for forming bumps such as solder. After the plating step, the resist 25 is removed (FIG. 13B). Then, by patterning each of the second electrode 9 and the seed layer using an etching method or the like, a non-formation portion 13 of the second electrode 9, the seed layer, and the inorganic film 16 is formed (FIG. 13C) (non-formation portion forming step). At this time, a state in which the second electrode 9 is separated for each semiconductor light-emitting element 3 is formed. That is, a state in which adjacent semiconductor light-emitting elements 3 are separated from each other in the non-formation portion forming step forms a state in which a plurality of semiconductor light-emitting elements 3 are formed on the element substrate 6. The element substrate 6 on which the plurality of semiconductor light-emitting elements 3 are formed is accommodated in a reflow furnace and subjected to a reflow process. As a result, a roundness is formed at the tip of the columnar body 23, and bumps 26 are formed on the plurality of semiconductor light-emitting elements 3 (FIG. 14C).

[0083] As a driving substrate 4 having a driving circuit, a substrate 17 on which a seed layer 18 and bumps 27 are formed at positions corresponding to the bumps 26 on the element substrate 6 described above is prepared (FIGS. 14A and 14B). The surface side of the substrate 17 on which the bumps 27 are formed is faced to the bumps 26 on the element substrate 6, and the substrate 17 is disposed on the element substrate 6.

[0084] The bump 27 formed on the substrate 17 constituting the driving substrate 4 is joined to the bump 26 formed on the element substrate 6. At this time, a bump joint portion 5 is formed (FIG. 14D). At this time, a state is formed in which the display panel 2 and the driving substrate 4 are connected at the bump joint portion. Examples of the joining method include a method of bringing the bump 27 on the driving substrate 4 side into contact with the bump 27 on the semiconductor light-emitting element 3 side in a state where the bumps 26 and 27 are melted, and a method of crimping the bump 27 on the driving substrate 4 side and the bump 26 on the semiconductor light-emitting element 3 side in a non-melted state of the bumps 26 and 27. After the bump joint portion 5 is formed, the gap space 24 between the display panel 2 and the driving substrate 4 is filled with an underfill material. Then, an underfill layer 21 is formed by curing the filled underfill material. In this way, the display device 1 is formed.

[0085] [2 Second Embodiment] [2-1 Configuration of Display Device] In the display device 1 according to the first embodiment, as shown in FIG. 15, the substrate joint region K formed at the other end (the other connection end 5B) may be larger than the element joint region J formed at one end (one connection end 5A) (second embodiment). That the substrate joint region K is larger than the element joint region J means that, as shown in FIGS. 15 and 16, when the Z-axis direction is the line-of-sight direction, the element joint region J is located inside the substrate joint region K. In the display device 1 according to the second embodiment as well, similar to the display device 1 according to the first embodiment, the case where the joint portion is the bump joint portion 5 will be taken as an example and the description will be continued.

[0086] From the viewpoint of ease of formation of the bump joint portion 5, as will be described later, it is preferable that the side surface portion 19 of the bump joint portion 5 forms a curved surface that is concave or convex from one connection end 5A along the Z-axis direction to the other connection end 5B.

[0087] When the bump joint portion 5 has a side surface portion that is concave-curved from one connection end 5A to the other connection end 5B, as shown in FIG. 15, the side surface portion 19 forms a curved surface such that the inclination gradually becomes gentle from the +Z direction toward the -Z direction. Note that the inclination indicates the gradient of the side surface portion 19 with respect to the horizontal plane (the XY plane spanned by the X-axis and the Y-axis). In the example of FIG. 15, for example, the gradient at the position T of the side surface portion 19 is indicated by the angle α formed between the tangent plane F at the position T of the side surface portion 19 and the horizontal plane E.

[0088] When the bump joint portion 5 has a side surface portion that is convex-curved from one connection end 5A to the other connection end 5B, as shown in the example of FIG. 17, the side surface portion 19 forms a curved surface such that the inclination gradually becomes steep from the +Z direction toward the -Z direction.

[0089] In the display device 1 according to the second embodiment, since the side surface portion is concave-curved or convex-curved from one connection end 5A to the other connection end 5B along the Z-axis direction of the bump joint portion 5, when the Z-axis direction is the line-of-sight direction, it becomes easy to form a state in which at least a part of the curved surface of the side surface portion 19 is positioned directly below the passing-through region Q. In particular, when the shape of the side surface portion 19 forms a concave curved surface in the display device 1 according to the second embodiment, the direction of the scattered light L2 is likely to be directed toward the light-emitting layer 12 side that is the source of the leakage light L1.

[0090] (Shape and position of substrate bonding region) In the example of FIG. 16, the shape of the substrate bonding region K is formed in a similar shape obtained by enlarging the shape of the element bonding region J. When the Z-axis direction is the line-of-sight direction, the center C K of the substrate bonding region K and the center C J of the element bonding region J are positioned such that they substantially coincide. Therefore, in the display device 1 shown in the examples of FIGS. 15 and 16, when the Z-axis direction is the line-of-sight direction, the center C R of the unit region R and the center C K of the substrate bonding region K formed in the bump joint portion 5 bonded to the semiconductor light-emitting element 3 corresponding to the unit region R are the center C of the element bonding region JJ Similarly, they are offset from each other in the X-axis direction. Here, the center C of the substrate bonding area K K As described in the first embodiment, the center C of the unit area R R 16, the substrate bonding area K is substantially circular, and the center C of the substrate bonding area K is K is the center of the circle. Also, the center C of the substrate bonding area K K Position deviation amount M K is the center C of the element junction region J described in the first embodiment. J 16, when the line of sight is the direction in which the display panel 2 and the drive substrate 4 face each other, the outer circumferential contour shape of the bump bonding portion 5 coincides with the substrate bonding area K. This also applies to the examples of FIGS. 18 to 23.

[0091] (effect) In the display device 1 according to the second embodiment, the center C J is the center C of unit area R R The substrate bonding area K is shifted from the light emitting layer 12, and the size of the substrate bonding area K is larger than the size of the element bonding area J. This makes it easier to form a state in which at least a part of the curved surface of the side surface portion 19 is disposed directly below the pass-through area Q. In this case, the scattered light L2 formed when the leakage light L1 propagating downward (-Z direction) from the light emitting layer 12 through the pass-through area Q is scattered by the curved surface of the side surface portion 19 of the bump bonding portion 5 is easily returned to the light emitting layer 12 side through the pass-through area Q through which the leakage light L1 passed, and is less likely to move toward the semiconductor light emitting element 3 side of the adjacent subpixel. This makes it possible to suppress the scattered light L2 from entering the area of ​​the adjacent subpixel in the display device 1.

[0092] [2-2 Modified Example] [Variation 1] (Modification of the shape of the substrate bonding area) In the example of the display device 1 in FIG. 16, the case where the shape of the substrate bonding region K is similar to the shape of the element bonding region J has been described. However, the display device 1 according to the second embodiment is not limited to this. As shown in FIG. 18, the shape of the substrate bonding region K and the shape of the element bonding region J may be dissimilar shapes and different from each other. For example, when the shape of the element bonding region J is circular, the shape of the substrate bonding region K may be a non-circular shape such as an elliptical shape or a rectangular shape. In the example of FIG. 18, the element bonding region J is formed in a circular shape, and the shape of the substrate bonding region K is formed in a substantially rectangular shape (a chamfered rectangular shape). Even in such a display device 1, it is possible to suppress the entry of scattered light into the regions of adjacent sub-pixels.

[0093] [Modification Example 2] (Modification Example in the Direction of Deviation of the Center of the Substrate Bonding Region) In the examples of the display device 1 in FIGS. 16 and 18, the element bonding region J of the bump bonding portion 5 is provided at a position deviated in the X-axis direction from the center of the unit region R, and the direction of the positional deviation of the element bonding region J is along the X-axis direction. In the display device according to the second embodiment, the direction of the positional deviation of the element bonding region J is not limited to the X-axis direction. The direction of the positional deviation of the element bonding region J may be, for example, a direction obliquely intersecting the X-axis within the plane spanned by the X-axis and the X-axis (the direction of arrow P in FIG. 19), similar to Modification Example 2 of the first embodiment, as shown in FIG. 19. Also, the amount of positional deviation M of the center C J of the element bonding region J in the P direction may be the same as the amount of positional deviation of the center C J of the element bonding region J described in the display device according to the first embodiment.

[0094] [Modification Example 3] In the description of the second embodiment and Modifications 1 and 2, the displacement direction of the element bonding region J of the bump bonding portion 5 was in one direction. However, the present invention is not limited to this example. Similar to Modification 4 of the first embodiment, for example, as shown in FIG. 20, a bump bonding portion 5 having the X-axis direction as the displacement direction of the element bonding region J and a bump bonding portion 5 having the Y-axis direction as the displacement direction of the element bonding region J may be connected to one semiconductor light-emitting element 3. In the example of FIG. 20, for both the bump bonding portion 5 having the X-axis direction as the displacement direction of the element bonding region J and the bump bonding portion 5 having the Y-axis direction as the displacement direction of the element bonding region J, the element bonding region J and the substrate bonding region K are rectangular, and a case where the substrate bonding region K is larger than the element bonding region J is illustrated.

[0095] [Modification 4] In the example of the display device 1 shown in Modification 3 of the second embodiment, the bump bonding portion 5 having the X-axis direction as the displacement direction and the bump bonding portion 5 having the Y-axis direction as the displacement direction were provided in a separated state. However, similar to Modification 5 of the first embodiment, the element bonding region J of the bump bonding portion 5 having the X-axis direction as the displacement direction and the element bonding region J of the bump bonding portion 5 having the Y-axis direction as the displacement direction may be connected to each other. This can be achieved, for example, by connecting the end portion in the longitudinal direction (Y direction) (-Y direction side end portion) of the bump bonding portion 5 having the X-axis direction as the displacement direction shown in FIG. 20 and the end portion in the longitudinal direction (X direction) (-X direction side end portion) of the bump bonding portion 5 having the Y-axis direction as the displacement direction. As a result, as shown in FIG. 21, a state in which the element bonding region J of the bump bonding portion 5 having the X-axis direction as the displacement direction and the element bonding region J of the bump bonding portion 5 having the Y-axis direction as the displacement direction are connected to each other can be easily formed. In the example of FIG. 21, the substrate bonding region K of the bump bonding portion 5 having the X-axis direction as the displacement direction shown in FIG. 20 and the substrate bonding region K of the bump bonding portion 5 having the Y-axis direction as the displacement direction are also connected to each other.

[0096] In the case of the example of FIG. 21, in the display device 1, the bump joint portion 5 is formed in an L-shaped configuration as a whole, and is disposed at a peripheral position (between adjacent unit regions R) of the semiconductor light-emitting element 3. In the bump joint portion 5 in this example, both the element joint region J and the substrate joint region K are formed in an L-shaped configuration as a whole, and the substrate joint region K is larger than the element joint region J. Note that the bump joint portion 5 is not limited to an L-shape, and may be formed in a U-shaped configuration or an annular configuration and may be disposed at a peripheral position of the semiconductor light-emitting element.

[0097] As shown in Modification Examples 1 to 4 above, in the display device 1, when the Z-axis direction is the line-of-sight direction, the shape of the substrate joint region K may be a shape selected from the group consisting of a circular shape, an elliptical shape, a rectangular shape, and an L-shaped configuration.

[0098] [Modification Example 5] (Honeycomb arrangement) Regarding the display device 1 according to the second embodiment as well, similar to Modification Example 6 of the first embodiment, as shown in FIGS. 22 and 23, each unit region R may be formed in a hexagonal shape, and these unit regions R may be arranged in a honeycomb pattern. In any of the examples of FIGS. 22 and 23, the substrate joint region K is larger than the element joint region J. In the example of FIG. 22, both the element joint region J and the substrate joint region K are formed in a rectangular shape. In the example of FIG. 23, the element joint region J is formed in a triangular shape, and the substrate joint region K is formed in a shape obtained by cutting out the corner portions of the triangle.

[0099] Note that, in the display device of FIG. 22, the center C of the element joint region J of the bump joint portion 5 as an example of the joint portion J is formed at a position shifted in the axial directions of the S1 axis, the S2 axis, and the S3 axis from the center of the unit region R. The S1 axis, the S2 axis, and the S3 axis are defined in the same manner as described in Modification Example 6 of the first embodiment, and are in a state of being defined in the direction in which the sides forming the adjacent unit regions R face each other.

[0100] In the display device shown in FIG. 23, the center C of the element bonding region J of the bump bonding portion 5 J is formed at a position shifted in the S4-axis direction from the center C of the unit region R R . The S4 axis is defined in the same manner as shown in Modification Example 6 of the first embodiment.

[0101] [3. Method for manufacturing a display device] Regarding the case where the display device is the display device 1 according to the second embodiment, the manufacturing method of the display device 1 is exemplified as shown in FIG. 24.

[0102] The same steps as those described in the manufacturing method of the display device according to the first embodiment are performed to form a state in which a plurality of semiconductor light-emitting elements 3 are formed on the element substrate 6. With the columnar body 23 formed on the element substrate 6 on which the plurality of semiconductor light-emitting elements 3 are formed, the element substrate 6 is placed in a reflow furnace. As a result, bumps 26 are formed on the element substrate 6 having the plurality of semiconductor light-emitting elements 3 (FIG. 24C).

[0103] As a driving substrate 4 having a driving circuit, a substrate 17 on which a seed layer 18 and bumps 27 are formed at positions corresponding to the bumps 26 on the element substrate 6 is prepared (driving substrate preparation step). This driving substrate preparation step is performed in the same manner as the manufacturing method of the display device according to the first embodiment, except that the size of the bumps 27 on the driving substrate 4 side (substrate 17 side) is formed larger than the size of the bumps 26 on the element substrate 6 side (FIG. 24A, FIG. 24B). Then, the bumps 26 and 27 are arranged such that the formation surface side of the bumps 27 on the substrate 17 side faces the formation surface side of the bumps 26 on the element substrate 6 side.

[0104] Next, the bump 27 on the substrate 17 side and the bump 26 on the element substrate 6 side are joined. At this time, the bump joint portion 5 is formed (Fig. 24D). As a method of joining the bumps 26 and 27, a method of bringing the bump 27 on the substrate 17 side into contact with the bump 26 on the element substrate 6 side in a state where the bumps 26 and 27 are melted is preferably employed. At this time, by determining various conditions such as the distance between the substrate 17 and the element substrate 6 and the reflow properties of the material for forming the bumps due to heat, a desired convex curved surface or a desired concave curved surface is formed on the side surface portion 19 of the bump joint portion 5. At this time, a state in which the driving substrate 4 and the display panel 2 are connected at the bump joint portion 5 is formed.

[0105] After the bump joint portion 5 is formed, the gap space 24 between the driving substrate 4 and the display panel 2 is filled with an underfill material. Then, an underfill layer 21 is formed by curing the filled underfill material. Thus, the display device 1 is formed.

[0106] [3 Third Embodiment] [3-1 Configuration of Display Device] In the display device 1 according to the first embodiment, the joint portion was the bump joint portion 5, but it is not limited thereto. As shown in Fig. 25, the joint portion may be formed by a Cu-Cu joint portion 30 (third embodiment).

[0107] In the display device according to the third embodiment, other configurations except for the Cu-Cu joint portion 30 may be the same as those of the display device according to the first embodiment.

[0108] (Cu-Cu Joint Portion 30) The Cu-Cu joint portion 30 can be formed, for example, by directly joining a Cu terminal 32 formed on the display panel 2 side and a Cu terminal 33 formed on the driving substrate 4 side (Cu-Cu joint). The Cu-Cu joint portion 30 shown in Fig. 25 has an inclined surface 34 on its side surface portion 19 that slopes upward in a direction (+Z direction) approaching the semiconductor light-emitting element 3 from a position far from the semiconductor light-emitting element 3.

[0109] In the display device 1 according to the third embodiment, the center C of the element bonding region J in the Cu-Cu joint 30 J is displaced from the center C of the unit region R R . The amount of displacement M of the center C of the element bonding region J J may be the same as the amount of displacement of the joint in the display device according to the first embodiment.

[0110] (Effect) Also in the display device 1 according to the third embodiment, as in the display device 1 according to the first embodiment, the center C of the element bonding region J J is displaced from the center C of the unit region R R , and the Cu-Cu joint 30 is arranged. Therefore, also in the display device 1 according to the third embodiment, as in the display device according to the first embodiment, it becomes easy to suppress scattered light from entering the regions of adjacent sub-pixels.

[0111] [3. Manufacturing method of the display device] Next, when the display device is the display device according to the third embodiment, the manufacturing method of the display device is exemplified as shown in FIGS. 26 and 27.

[0112] Similar to the manufacturing method of the display device 1 according to the first embodiment, the first compound semiconductor layer 10, the light-emitting layer 12, and the second compound semiconductor layer 11 are patterned in this order on the first main surface of the element substrate 6. Also, the first electrode 8 is formed at a predetermined position. Similar to the manufacturing method of the display device according to the first embodiment, each step up to the inorganic film forming step is performed. Then, a non-formation portion forming step is performed in the same manner as the manufacturing method of the display device 1 according to the first embodiment. That is, by patterning each of the second electrode 9, the seed layer 15, and the inorganic film 16 using an etching method or the like, non-formation portions 13 of the second electrode 9, the seed layer 15, and the inorganic film 16 are formed. At this time, the second electrode 9 is separated for each semiconductor light-emitting element 3, and a plurality of semiconductor light-emitting elements 3 are formed. Note that, unlike the display device 1 according to the first embodiment, the plating step is omitted.

[0113] An underfill material is applied to the formation surface side of the stacked structure 7 on the element substrate 6, and an underfill layer 35 is formed (FIG. 26A). A groove 36 is formed at a predetermined position of the underfill layer using a lithography method, an etching method, or the like (FIG. 26B). In FIG. 26B, reference numeral 37 denotes a resist. Next, except for the resist 37, copper is plated on the formation surface side of the groove 36 using a sputtering method or the like. At this time, the groove 36 is filled with copper, and a copper film 38 is further formed on the surface of the element substrate 6 on the formation surface side of the stacked structure 7 (FIG. 26C). The copper adhering to the outside of the groove in the copper film 38 is removed by a surface flattening process (FIG. 26D). Thereby, a first substrate structure 40 in which the Cu terminal 32 is electrically connected to the stacked structure 7 forming the semiconductor light-emitting element 3 is formed (FIG. 27E).

[0114] On the surface of the substrate 17 constituting the drive substrate 4 having a drive circuit, a Cu terminal 33 is formed at a position corresponding to the Cu terminal 32 of the first substrate structure 40, and a barrier layer 42 is formed on the Cu terminal 33 (FIG. 27A). Next, an underfill layer 39 is disposed so as to cover the barrier layer 42 (FIG. 27B). Then, a surface flattening process is performed to expose the Cu terminal 33 (FIG. 27C). Thus, a second substrate structure 41 is prepared (FIG. 27D). Then, the Cu terminal 33 of the second substrate structure 41 is disposed facing the Cu terminal 32 of the first substrate structure 40 (FIGS. 27D and 27E).

[0115] The Cu terminal 33 of the second substrate structure 41 and the Cu terminal 32 of the first substrate structure 40 are joined. At this time, the underfill layer 39 of the second substrate structure 41 and the underfill layer 35 of the first substrate structure 40 are also joined. Thus, the first substrate structure 40 and the second substrate structure 41 are joined. Thereby, a state in which the display panel 2 and the drive substrate 4 are joined via the Cu-Cu joint 30 is formed, and the display device 1 is formed. From the viewpoint of facilitating the joining of the underfill layers 35 and 39, the underfill layer 35 and the underfill layer 39 are preferably made of the same material.

[0116] As described above, the examples of the embodiments of the present disclosure have been specifically described. However, the present disclosure is not limited to the examples of the above-described embodiments, and various modifications based on the technical idea of the present disclosure are possible.

[0117] For example, the configurations, methods, steps, shapes, materials, numerical values, etc. cited in the examples of the above-described embodiments are merely examples, and different configurations, methods, steps, shapes, materials, numerical values, etc. may be used as necessary.

[0118] In addition, the configurations, methods, steps, shapes, materials, numerical values, etc. cited in the examples of the above-described embodiments can be combined with each other as long as the gist of the present disclosure is not deviated from.

[0119] The materials exemplified in the above-described embodiments can be used singly or in combination of two or more without particular notice.

[0120] Note that the content of the present disclosure is not limitedly interpreted by the effects exemplified in the present disclosure.

[0121] The present disclosure can also adopt the following configurations. (1) A display panel having a plurality of semiconductor light-emitting elements including a light-emitting layer, A driving substrate having a driving circuit facing the display panel, And a plurality of bonding portions for electrically connecting the plurality of semiconductor light-emitting elements to the driving substrate respectively, When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the position of the center of the light-emitting region of the semiconductor light-emitting element and the position of the center of the bonding portion bonded to the semiconductor light-emitting element are displaced from each other. A display device. (2) The magnitude of the displacement between the center of the bonding portion and the center of the light-emitting region is 1 / 4 or more and 3 / 4 or less of the center-to-center distance of the adjacent light-emitting regions along the direction of the displacement. The display device according to (1) above. (3) The magnitude of the displacement between the center of the joint portion and the center of the light-emitting region is approximately 1 / 2 of the center-to-center distance of the adjacent light-emitting regions along the direction of the displacement. The display device according to (1) above. (4) When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the plurality of semiconductor light-emitting elements are two-dimensionally arranged. The direction of the displacement between the center of the joint portion and the center of the light-emitting region is along the arrangement direction of the semiconductor light-emitting elements. The display device according to any one of (1) to (3) above. (5) The adjacent light-emitting regions are spaced apart. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the joint portion is located within the region between the adjacent light-emitting regions. The display device according to any one of (1) to (4) above. (6) A through-passage region through which light propagates toward the driving substrate is formed in a part of the light-emitting region. The joint portion has a convexly curved side surface portion, and an extended surface with a gentler inclination than the side surface portion is formed between the end portion of the joint portion and the side surface portion. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the extended surface faces the through-passage region. The display device according to any one of (1) to (5) above. (7) The joint portion is a bump joint portion. The display device according to any one of (1) to (6) above. (8) The bump joint portion has a convexly curved side surface portion. The display device according to (7) above. (9) An element bonding region is formed at one end of the joint portion along the direction in which the display panel and the driving substrate face each other, and a substrate bonding region to be bonded to the driving substrate is formed at the other end. The substrate bonding region formed at the other end is larger than the element bonding region formed at the one end. The display device according to any one of (1) to (8) above. (10) The joint portion has a side surface portion that is curved in a concave or convex shape from the one end to the other end. The display device according to (9), which is dependent on any one of (1) to (7) above. (11) When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the shape of the substrate joint region has a shape selected from the group consisting of a circular shape, an elliptical shape, a rectangular shape, and an L-shaped shape. The display device according to (9) or (10) above. (12) The joint portion is formed of a material having reflow properties. The display device according to any one of (1) to (11) above. (13) The joint portion is a Cu-Cu joint portion. The display device according to any one of (1) to (6) above. (14) When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the shape of the joint portion has a shape selected from the group consisting of a circular shape, an elliptical shape, a rectangular shape, and an L-shaped shape. The display device according to any one of (1) to (13) above. (15) A plurality of the light-emitting regions corresponding to the plurality of the semiconductor light-emitting elements are arranged in a matrix shape or a honeycomb shape. The display device according to any one of (1) to (14) above. (16) Each of the plurality of the semiconductor light-emitting elements is a micro LED. The display device according to any one of (1) to (15) above. (17) The emission colors of adjacent semiconductor light-emitting elements are different from each other. The display device according to any one of (1) to (16) above.

Description of reference numerals

[0122] 1 Display device 2 Display panel 3 Semiconductor light-emitting element 4 Driving substrate 5 Bump joint portion (joint portion) 7 Laminated structure 8 First electrode 9 Second electrode 10 First compound semiconductor layer 11 Second compound semiconductor layer 12 Light-emitting layer 13 Non-formation part 14 Insulating layer 17 Substrate 18 Seed layer 30 Cu-Cu joint (joint)

Claims

1. A display panel having a plurality of semiconductor light-emitting elements each including a light-emitting layer, a driving substrate having a driving circuit and facing the display panel, and a plurality of bonding portions each electrically connecting one of the plurality of semiconductor light-emitting elements to the driving substrate, wherein when the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the position of the center of the light-emitting region of the semiconductor light-emitting element and the position of the center of the bonding portion bonded to the semiconductor light-emitting element are shifted from each other, a passage region through which light propagates toward the driving substrate is formed in a part of the light-emitting region, the bonding portion has a side surface curved in a convex shape, and an extending surface having a gentler inclination than the side surface is formed between an end portion of the bonding portion and the side surface, and when the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the extending surface faces the passage region, a display device.

2. The magnitude of the positional shift between the center of the bonding portion and the center of the light-emitting region is 1 / 4 or more and 3 / 4 or less of the center-to-center distance between adjacent light-emitting regions along the direction of the positional shift, The display device according to Claim 1.

3. The magnitude of the positional shift between the center of the bonding portion and the center of the light-emitting region is about 1 / 2 of the center-to-center distance between adjacent light-emitting regions along the direction of the positional shift, The display device according to Claim 1.

4. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the plurality of semiconductor light-emitting elements are two-dimensionally arranged, and the direction of the positional shift between the center of the bonding portion and the center of the light-emitting region is along the arrangement direction of the semiconductor light-emitting elements, The display device according to Claim 1.

5. Adjacent light-emitting regions are spaced apart from each other, and when the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the bonding portion is located within a region between adjacent light-emitting regions, The display device according to Claim 1.

6. The bonding portion is a bump bonding portion, The display device according to Claim 1.

7. The bonding portion is formed of a material having reflow properties, The display device according to Claim 1.

8. The bonding portion is a Cu-Cu bonding portion, The display device according to Claim 1.

9. When the direction in which the display panel and the driving substrate face each other is defined as the line-of-sight direction, the shape of the bonding portion has a shape selected from the group consisting of a circular shape, an elliptical shape, a rectangular shape, and an L-shaped shape, The display device according to Claim 1.

10. The plurality of light-emitting regions corresponding to the plurality of semiconductor light-emitting elements are arranged in a matrix or honeycomb pattern. The display device according to claim 1.

11. Each of the plurality of semiconductor light-emitting elements is a micro LED. The display device according to claim 1.

12. The emission colors of adjacent semiconductor light-emitting elements are different from each other. The display device according to claim 1.

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