阅读说明：本技术 阵列基板、显示装置以及显示装置的制造方法 (Array substrate, display device and manufacturing method of display device ) 是由 矶野大树 山田一幸 浅田圭介 武政健一 于 2021-03-24 设计创作，主要内容包括：本发明提供一种即使更换无机发光二极管也可抑制对电极的损伤的阵列基板、显示装置以及显示装置的制造方法。阵列基板具备：基板；层叠于基板的第一绝缘膜；以及设在第一绝缘膜之上、且用于与无机发光二极管的阳极电极电连接的多个第1电极。第1电极具有经由接合用导电体与阳极电极接合的第1区域、以及位于与第1区域不同的位置的第2区域。多个第2区域中包括存在加热痕的第2区域。(The invention provides an array substrate, a display device and a manufacturing method of the display device, wherein damage to an electrode can be inhibited even if an inorganic light emitting diode is replaced. The array substrate includes: a substrate; a first insulating film laminated on the substrate; and a plurality of No. 1 electrodes disposed on the first insulating film and electrically connected to the anode electrode of the inorganic light emitting diode. The 1 st electrode has a 1 st region bonded to the anode electrode via the bonding conductor, and a 2 nd region located at a position different from the 1 st region. The plurality of 2 nd regions include a 2 nd region where a heating mark exists.)

1. An array substrate, comprising:

a substrate;

a first insulating film laminated on the substrate; and

a plurality of No. 1 electrodes provided on the first insulating film and electrically connected to an anode electrode of the inorganic light emitting diode,

the 1 st electrode has a 1 st region bonded to the anode electrode via a bonding conductor, and a 2 nd region located at a position different from the 1 st region,

the plurality of 2 nd regions include a 2 nd region where a heating mark exists.

2. The array substrate of claim 1,

the 1 st region is located closer to the substrate than the 2 nd region.

3. The array substrate of claim 1,

further comprising a second insulating film provided on the first insulating film and having a convex portion protruding from the 1 st region,

the 2 nd region is disposed over the second insulating film.

4. The array substrate of claim 1,

further comprising a second insulating film provided on the first insulating film, surrounding the 1 st region, and having a convex portion protruding from the first insulating film,

the 2 nd region is disposed over the second insulating film.

5. The array substrate of claim 1,

the bonding conductor has a melting point lower than that of the material of the surface of the 1 st electrode.

6. The array substrate of claim 1,

further comprising a 3 rd electrode embedded in the first insulating film between the substrate and the 1 st electrode,

the 1 st region of the 1 st electrode is separated from the 2 nd region of the 1 st electrode,

the 1 st region of the 1 st electrode and the 2 nd region of the 1 st electrode are connected to the 3 rd electrode via contact holes, respectively.

7. The array substrate of claim 1,

and a 3 rd electrode which is located between the substrate and the 1 st electrode, is embedded in the first insulating film, and is electrically connected to a switching element for driving the inorganic light emitting diode,

the 1 st electrode is connected to the 3 rd electrode via a contact hole,

the 3 rd electrode includes an oxide conductor.

8. The array substrate of claim 1,

and a plurality of No. 2 electrodes provided on the first insulating film and electrically connected to the cathode electrodes of the inorganic light emitting diodes,

the 2 nd electrode has a 3 rd region to which the cathode electrode is bonded to the 2 nd electrode via a bonding conductor, and a 4 th region located at a position different from the 3 rd region,

the 4 th region includes a 4 th region where a heating mark exists.

9. A display device is characterized by comprising:

an array substrate; and

a plurality of inorganic light emitting diodes bonded to the array substrate,

the array substrate includes: a substrate; a first insulating film laminated on the substrate; and a plurality of 1 st electrodes provided on the first insulating film and electrically connected to an anode electrode of the inorganic light emitting diode, wherein the 1 st electrodes have a 1 st region bonded to the anode electrode via a bonding conductor and a 2 nd region located at a position different from the 1 st region, and the plurality of 2 nd regions include a 2 nd region where a heating mark exists.

10. The display device according to claim 9,

the 1 st region is located closer to the substrate than the 2 nd region.

11. The display device according to claim 9,

further comprising a second insulating film provided on the first insulating film and having a convex portion protruding from the 1 st region,

the 2 nd region is disposed over the second insulating film.

12. The display device according to claim 9,

further comprising a second insulating film provided on the first insulating film, surrounding the 1 st region, and having a convex portion protruding from the first insulating film,

the 2 nd region is disposed over the second insulating film.

13. The display device according to claim 9,

the bonding conductor has a melting point lower than that of the material of the surface of the 1 st electrode.

14. The display device according to claim 9,

a 3 rd electrode embedded in the first insulating film between the substrate and the 1 st electrode,

the 1 st region of the 1 st electrode is separated from the 2 nd region of the 1 st electrode,

the 1 st region of the 1 st electrode and the 2 nd region of the 1 st electrode are connected to the 3 rd electrode via contact holes, respectively.

15. The display device according to claim 9,

a 3 rd electrode which is located between the substrate and the 1 st electrode, is embedded in the first insulating film, and is electrically connected to a switching element for driving the inorganic light emitting diode,

the 1 st electrode is connected to the 3 rd electrode via a contact hole,

the 3 rd electrode includes an oxide conductor.

16. The display device according to claim 9,

and a plurality of No. 2 electrodes provided on the first insulating film and electrically connected to the cathode electrodes of the inorganic light emitting diodes,

the 2 nd electrode has a 3 rd region to which the cathode electrode is bonded to the 2 nd electrode via a bonding conductor, and a 4 th region located at a position different from the 3 rd region,

the 4 th region includes a 4 th region where a heating mark exists.

17. A method of manufacturing a display device, comprising:

a substrate preparation step of preparing an array substrate including a substrate, a first insulating film laminated on the substrate, and a plurality of 1 st electrodes provided on the first insulating film and electrically connected to an anode electrode of an inorganic light emitting diode, the 1 st electrodes having a 1 st region bonded to the anode electrode via a bonding conductor and a 2 nd region located at a position different from the 1 st region;

a bonding step of bonding the inorganic light emitting diode and the 1 st region via a bonding conductor;

a lighting inspection step of inspecting a lighting state of the inorganic light emitting diode; and

and a repairing step of irradiating a 2 nd region of the 1 st electrode to which the inorganic light emitting diode identified as requiring repair in the lighting inspection step is bonded with laser light to remove the inorganic light emitting diode.

18. The method for manufacturing a display device according to claim 17,

the array substrate further includes a plurality of No. 2 electrodes disposed on the first insulating film and electrically connected to cathode electrodes of the inorganic light emitting diodes,

the 2 nd electrode has a 3 rd region to which the cathode electrode is bonded to the 2 nd electrode via a bonding conductor, and a 4 th region located at a position different from the 3 rd region,

in the repairing step, the 4 th region of the 2 nd electrode to which the inorganic light emitting diode identified as requiring repair in the lighting inspection step is bonded is irradiated with laser light to remove the inorganic light emitting diode.

Technical Field

The present disclosure relates to an array substrate, a display device, and a method of manufacturing the display device.

Background

In a display device using light emitting diodes, it is difficult to mount the light emitting diodes on a substrate or to manufacture the light emitting diodes because of the small size of the light emitting diodes, which tends to cause defects in the light emitting diodes. When such a display device is not used by eliminating the display device in which a defect occurs, the yield is reduced. Therefore, in the display device using the light emitting diode, even when a failure of the light emitting diode occurs, the light emitting diode needs to be replaced. For example, patent document 1 describes a repair method for replacing a light emitting diode.

Documents of the prior art

Patent document

Patent document 1: specification of U.S. patent application publication No. 2017/0140961

Disclosure of Invention

In the technique of patent document 1, a pickup tool (holding member) is used. In a state where a light emitting diode that needs to be replaced is bonded to the array substrate, if the light emitting diode is peeled off from the array substrate by a pick-up tool (holding member), the electrode on the array substrate side may be damaged.

An object of the present disclosure is to provide an array substrate, a display device, and a method for manufacturing a display device, in which damage to an electrode can be suppressed even when an inorganic light emitting diode is replaced.

An array substrate according to one aspect includes: a substrate; a first insulating film laminated on the substrate; and a plurality of 1 st electrodes provided on the first insulating film and electrically connected to an anode electrode of the inorganic light emitting diode, wherein the 1 st electrode has a 1 st region bonded to the anode electrode via a bonding conductor and a 2 nd region located at a position different from the 1 st region, and the plurality of 2 nd regions include a 2 nd region where a heating mark exists.

A display device according to one aspect includes: an array substrate; and a plurality of inorganic light emitting diodes bonded to the array substrate, the array substrate including: a substrate; a first insulating film laminated on the substrate; and a plurality of 1 st electrodes provided on the first insulating film and electrically connected to an anode electrode of the inorganic light emitting diode, wherein the 1 st electrodes have a 1 st region bonded to the anode electrode via a bonding conductor and a 2 nd region located at a position different from the 1 st region, and the plurality of 2 nd regions include a 2 nd region where a heating mark exists.

A method of manufacturing a display device of one aspect includes: a substrate preparation step of preparing an array substrate including a substrate, a first insulating film laminated on the substrate, and a plurality of 1 st electrodes provided on the first insulating film and electrically connected to an anode electrode of an inorganic light emitting diode, the 1 st electrodes having a 1 st region bonded to the anode electrode via a bonding conductor and a 2 nd region located at a position different from the 1 st region; a bonding step of bonding the inorganic light emitting diode and the 1 st region via a bonding conductor; a lighting inspection step of inspecting a lighting state of the inorganic light emitting diode; and a repairing step of irradiating a 2 nd region of the 1 st electrode bonded to the inorganic light emitting diode which is confirmed to be required to be repaired in the lighting inspection step with laser light to remove the inorganic light emitting diode.

Drawings

Fig. 1 is a plan view schematically showing a display device of embodiment 1.

Fig. 2 is a circuit diagram showing a pixel circuit of the display device.

Fig. 3 is a sectional view in the direction of arrows along the line III-III' of fig. 1.

Fig. 4 is an explanatory view for schematically explaining the connection between the array substrate and the light emitting element.

Fig. 5 is a plan view schematically illustrating the 1 st electrode and the 2 nd electrode in embodiment 1.

Fig. 6 is an explanatory view for explaining a part of the steps of the manufacturing method in embodiment 1.

Fig. 7 is an explanatory diagram showing a configuration of a manufacturing apparatus of a display device according to embodiment 1.

Fig. 8 is an explanatory diagram for explaining an influence of irradiation with laser light.

Fig. 9 is a sectional view of the display device according to embodiment 2.

Fig. 10 is a plan view schematically illustrating a 1 st electrode in embodiment 2.

Fig. 11 is an explanatory view for explaining a part of the steps of the manufacturing method in embodiment 2.

Fig. 12 is an explanatory diagram showing a configuration of a manufacturing apparatus of a display device according to embodiment 2.

Fig. 13 is a sectional view of the display device according to embodiment 3.

Fig. 14 is a sectional view of the display device according to embodiment 4.

Fig. 15 is a plan view schematically illustrating a 1 st electrode in embodiment 4.

Fig. 16 is a sectional view of the display device according to embodiment 5.

Wherein the reference numerals are as follows:

1 display device

2 array substrate

3. 3N, 3A, 3AN light emitting element

5 cover part

8-lighting inspection device

21 substrate

22 nd electrode

22A region 3

22B region 4

23 st electrode

23A region 1

23B region 2

24 rd 3 electrode

36 anode electrode

38 cathode electrode

39A, 39B bonding conductor

81 inspection substrate

82 electrode for inspection

91 insulating film

92 insulating film

93 insulating film

94 insulating film

95 insulating film

96 insulating film

97a opening

97 insulating film

98 insulating film

100 manufacturing system

101 control circuit for inspection

102 photo detection device

103 image processing circuit

104 test drive circuit

105 laser device

200 pick-up tool

Detailed Description

Modes (embodiments) for carrying out the invention will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. The components described below include components that can be easily conceived by those skilled in the art or that are substantially the same. The following constituent elements can be appropriately combined. The disclosure is merely an example, and appropriate modifications that can be easily made by those skilled in the art while maintaining the spirit of the invention are naturally included in the scope of the disclosure. In addition, in order to make the description clearer, the width, thickness, shape, and the like of each part in the drawings are schematically shown as compared with the actual form in some cases, but the present disclosure is not limited to the example. In the present disclosure and the drawings, the same elements as those already described in the drawings are denoted by the same reference numerals, and detailed description thereof may be omitted as appropriate.

(embodiment mode 1)

Fig. 1 is a plan view schematically showing a display device of embodiment 1. Fig. 2 is a circuit diagram showing a pixel circuit of the display device. Fig. 3 is a sectional view in the direction of arrows along the line III-III' of fig. 1. As shown in fig. 1, the display device 1 includes an array substrate 2, a plurality of pixels Pix, a driving Circuit 12, a driving IC (Integrated Circuit) 200, and a cathode wiring 26. The array substrate 2 is a wiring substrate for driving the pixels Pix. The array substrate 2 is also referred to as a backplane or an active matrix substrate. The array substrate 2 includes a substrate 21 (see fig. 1 and 3), a 1 st transistor Tr1 (see fig. 2 and 3), a 2 nd transistor Tr2 (see fig. 2 and 3), and the like formed on the substrate 21, a transistor TrG (see fig. 3), various wirings, and the like. The 1 st transistor Tr1, the 2 nd transistor Tr2, and the like are switching elements provided for each pixel Pix. The transistor TrG is a switching element included in the drive circuit 12.

As shown in fig. 1, the display device 1 has a display area AA and a peripheral area GA. The display area AA is an area where an image is displayed, and is arranged to overlap with the plurality of pixels Pix. The peripheral area GA is an area not overlapping with the plurality of pixels Pix, and is disposed outside the display area AA.

The plurality of pixels Pix are arranged in the display area AA of the substrate 21 along the 1 st direction Dx and the 2 nd direction Dy. The 1 st direction Dx and the 2 nd direction Dy are parallel to the surface of the substrate 21. A direction parallel to a plane including the 1 st direction Dx and the 2 nd direction Dy may be referred to as a planar direction. The 1 st direction Dx is orthogonal to the 2 nd direction Dy. Therefore, Dy in the 2 nd direction may be referred to as an orthogonal direction. Here, the 1 st direction Dx includes a case where it does not intersect the 2 nd direction Dy at right angles. The 3 rd direction Dz is a direction orthogonal to the 1 st direction Dx and the 2 nd direction Dy, and may be referred to as a stacking direction.

The drive circuit 12 is a circuit that drives a plurality of gate lines based on various control signals from the drive IC 200. The plurality of gate lines include the 1 st gate line GCL1 and the 2 nd gate line GCL2 shown in fig. 2. The driving circuit 12 sequentially or simultaneously selects a plurality of gate lines and supplies a gate driving signal to the selected gate lines. Thereby, the driving circuit 12 selects the plurality of pixels Pix connected to the gate lines.

The driver IC200 is a circuit that controls display of the display device 1. The driver IC200 is mounted as a COG (Chip On Glass) in the peripheral area GA of the substrate 21. However, the driver IC200 may be mounted as a COF (Chip On Film) On a flexible printed circuit board or a rigid substrate connected to the peripheral area GA of the substrate 21.

The cathode wiring 26 is provided in the peripheral area GA of the substrate 21. The cathode line 26 is provided so as to surround the plurality of pixels Pix in the display area AA and the drive circuit 12 in the peripheral area GA. Cathodes of the plurality of light emitting elements 3 are connected to a common cathode wiring 26, and are supplied with a ground potential, for example. In embodiment 1, the cathode line 26 is connected to the 2 nd electrode 22 described later.

The pixel Pix has a light emitting element 3. The light emitting element 3 is provided corresponding to the pixel Pix, and includes a 1 st light emitting element 3R, a 2 nd light emitting element 3G, and a 3 rd light emitting element 3B that emit light of different colors. The 1 st light emitting element 3R emits red light. The 2 nd light emitting element 3G emits green light. The 3 rd light emitting element 3B emits blue light. In the following description, when it is not necessary to separately describe the 1 st light-emitting element 3R, the 2 nd light-emitting element 3G, and the 3 rd light-emitting element 3B, only the light-emitting element 3 is shown. The plurality of light emitting elements 3 may emit different light of 4 colors or more.

The arrangement of the pixels Pix repeats the arrangement of the pixels Pix having the 1 st light emitting element 3R, the pixels Pix having the 2 nd light emitting element 3G, and the pixels Pix having the 3 rd light emitting element 3B in the 1 st direction Dx. That is, the 1 st light emitting element 3R, the 2 nd light emitting element 3G, and the 3 rd light emitting element 3B are repeatedly arranged in this order along the 1 st direction Dx. In addition, a plurality of 1 st light emitting elements 3R, 2 nd light emitting elements 3G, and 3 rd light emitting elements 3B are arranged in series in the 2 nd direction Dy.

The Light Emitting element 3 is an inorganic Light Emitting Diode (LED) chip having a size of about 3 μm to 300 μm in a plan view, and is called a micro LED (micro LED). A display device having a micro LED in each pixel is also referred to as a micro LED display device. In addition, the micro size of the micro LED is not limited to the size of the inorganic light emitting diode. The light emitting element 3 may be a mini LED.

The pixel circuit 28 is a driving circuit for driving the light emitting element 3. As shown in fig. 2, the pixel circuit 28 has a plurality of switching elements (a 1 st transistor Tr1, a 2 nd transistor Tr2, a 3 rd transistor Tr3, and a 4 th transistor Tr4), and a 1 st gate line GCL1, a 2 nd gate line GCL2, a signal line SGL, and a power supply line LVdd. Each Transistor is a Thin Film Transistor (TFT).

The 1 st transistor Tr1 is a driving TFT. The 2 nd transistor Tr2 is a switching TFT for an emission period and a non-emission period. The 3 rd transistor Tr3 and the 4 th transistor Tr4 are current switching TFTs. The signal line SGL is connected to a constant current source. The power supply line LVdd is connected to a constant voltage source.

Further, a storage capacitor CS1 is formed between the drain of the 2 nd transistor Tr2 and the anode of the light emitting element 3. Further, a holding capacitor CS2 is formed between the anode of the light-emitting element 3 and the power supply line LVdd. The pixel 2 circuit 8 suppresses variation in the gate voltage due to the parasitic capacitance and the leakage current of the 2 nd transistor Tr2 by the storage capacitor CS1 and the storage capacitor CS 2.

In the non-emission period, the drive circuit 12 (see fig. 1) sets the potential of the 1 st gate line GCL1 to a high level and the potential of the 2 nd gate line GCL2 to a low level. Thereby, the 2 nd transistor Tr2 and the 3 rd transistor Tr3 are turned on, and the 4 th transistor Tr4 is turned off. A current Idata is supplied from the signal line SGL to the anode of the light-emitting element 3.

In the light emission period, the drive circuit 12 (see fig. 1) sets the potential of the 1 st gate line GCL1 to low level and the potential of the 2 nd gate line GCL2 to high level. Thereby, the 2 nd transistor Tr2 and the 3 rd transistor Tr3 are turned off, and the 4 th transistor Tr4 is turned on. The current Id is supplied from the power supply line LVdd to the anode of the light emitting element 3. Note that fig. 2 is merely an example, and the configuration of the pixel circuit 28 and the operation of the display device 1 can be changed as appropriate.

As shown in fig. 3, the light emitting element 3 is provided on the array substrate 2. The array substrate 2 includes a substrate 21, switching elements such as a 1 st transistor Tr1 and a 2 nd transistor Tr2, and various wirings and various insulating films. As the plurality of transistors, a transistor TrG included in the drive circuit 12 is provided in the peripheral area GA of the substrate 21. The substrate 21 is an insulating substrate, and for example, a glass substrate, a resin film, or the like is used.

In the present disclosure, a direction from the substrate 21 toward the upper surface 27a of the planarization film 27 in a direction perpendicular to the surface of the substrate 21 is set to be "upper side". The direction from the upper surface 27a of the planarization film 27 toward the substrate 21 is referred to as "lower side". In addition, the "plan view" shows a view from a direction perpendicular to the surface of the substrate 21.

The 1 st transistor Tr1, the 2 nd transistor Tr2, and the transistor TrG are provided on one surface side of the substrate 21. The 1 st transistor Tr1 includes a semiconductor 61, a source electrode 62, a drain electrode 63, a 1 st gate electrode 64A, and a 2 nd gate electrode 64B. The 1 st gate electrode 64A is provided on the substrate 21 via the 1 st insulating film 91. The 1 st insulating film 91 is formed of an inorganic insulating material such as a silicon oxide film (SiO), a silicon nitride film (SiN), or a silicon oxynitride film (SiON). Each inorganic insulating film is not limited to a single layer, and may be a laminated film.

The 2 nd insulating film 92 is provided on the 1 st insulating film 91 so as to cover the 1 st gate electrode 64A. The 2 nd insulating film 92 is made of an inorganic insulating material such as a silicon oxide film (SiO), a silicon nitride film (SiN), or a silicon oxynitride film (SiON). Each inorganic insulating film is not limited to a single layer, and may be a laminated film.

The semiconductor 61 is provided over the 2 nd insulating film 92. The 3 rd insulating film 93 is provided on the 2 nd insulating film 92 so as to cover the semiconductor 61. The 2 nd gate electrode 64B is provided over the 3 rd insulating film 93. The semiconductor 61 is provided between the 1 st gate electrode 64A and the 2 nd gate electrode 64B in the 3 rd direction Dz. In the semiconductor 61, a channel region is formed in a portion sandwiched between the 1 st gate electrode 64A and the 2 nd gate electrode 64B.

In the example shown in fig. 3, the 1 st transistor Tr1 is of a so-called double gate configuration. Here, the 1 st transistor Tr1 may have a bottom gate structure in which the 1 st gate electrode 64A is provided and the 2 nd gate electrode 64B is not provided, or may have a top gate structure in which the 1 st gate electrode 64A is not provided and only the 2 nd gate electrode 64B is provided.

The semiconductor 61 is made of, for example, amorphous silicon, microcrystalline oxide semiconductor, amorphous oxide semiconductor, Polycrystalline silicon, Low Temperature Polycrystalline Silicon (LTPS), or gallium nitride (GaN). As the oxide semiconductor, IGZO, zinc oxide (ZnO), and ITZO are exemplified. IGZO is indium gallium zinc oxide. ITZO is indium tin zinc oxide.

A 4 th insulating film 94 is provided on the 3 rd insulating film 93 so as to cover the 2 nd gate electrode 64B. The 4 th insulating film 94 is a light-transmitting organic insulating film, and is made of a resin material such as silicone resin, epoxy resin, acrylic resin, or polyimide resin. The source electrode 62 and the drain electrode 63 are provided on the 4 th insulating film 94. In this embodiment mode, the source electrode 62 is electrically connected to the semiconductor 61 through the contact hole H5. The drain electrode 63 is electrically connected to the semiconductor 61 through the contact hole H3.

A 5 th insulating film 95 is provided on the 4 th insulating film 94 so as to cover the source electrode 62 and the drain electrode 63. The 5 th insulating film 95 is a planarizing film which planarizes irregularities formed by the 1 st transistor Tr1 and various wirings. The 5 th insulating film 95 is a light-transmitting organic insulating film, and a resin material such as a silicone resin, an epoxy resin, an acrylic resin, or a polyimide resin is used.

The 2 nd transistor Tr2 includes a semiconductor 65, a source electrode 66, a drain electrode 67, a 1 st gate electrode 68A, and a 2 nd gate electrode 68B. The 2 nd transistor Tr2 has a similar layer configuration to that of the 1 st transistor Tr1, and detailed description is omitted. The drain electrode 67 of the 2 nd transistor Tr2 is connected to the connection wiring 69 via the contact hole H8. The connection wiring 69 is connected to the 1 st gate electrode 64A and the 2 nd gate electrode 64B of the 1 st transistor Tr 1.

The semiconductor 65, the source electrode 66, the drain electrode 67, the 1 st gate electrode 68A, and the 2 nd gate electrode 68B may be provided in the same layer as or in a different layer from the semiconductor 61, the source electrode 62, the drain electrode 63, the 1 st gate electrode 64A, and the 2 nd gate electrode 64B of the 1 st transistor Tr1, respectively.

The transistor TrG includes a semiconductor 71, a source electrode 72, a drain electrode 73, a 1 st gate electrode 74A, and a 2 nd gate electrode 74B. The transistor TrG is a switching element included in the drive circuit 12. The transistor TrG also has a similar layer configuration to the 1 st transistor Tr1, and detailed description is omitted. In addition, the 3 rd transistor Tr3 and the 4 th transistor Tr4 (refer to fig. 2) also have a similar layer configuration as the 1 st transistor Tr 1.

The 4 th electrode 25 extends on the 5 th insulating film 95, and faces the 2 nd electrode 22 in the 3 rd direction Dz via the 6 th insulating film 96. Thereby, a capacitance is formed between the 2 nd electrode 22 and the 4 th electrode 25. The capacitance formed between the 2 nd electrode 22 and the 4 th electrode 25 is used as the holding capacitance CS of the pixel circuit 28. The 6 th insulating film 96 is formed using an inorganic insulating material such as a silicon oxide film (SiO), a silicon nitride film (SiN), or a silicon oxynitride film (SiON). Each inorganic insulating film is not limited to a single layer, and may be a laminated film.

The 7 th insulating film 97 is provided on the 2 nd electrode 22, the 1 st electrode 23, and the 6 th insulating film 96. The 7 th insulating film 97 has an opening 97a for connecting the 1 st electrode 23 and the 2 nd electrode 22 to the light-emitting element 3. The 7 th insulating film 97 is formed using an inorganic insulating material such as a silicon oxide film (SiO), a silicon nitride film (SiN), or a silicon oxynitride film (SiON). Each inorganic insulating film is not limited to a single layer, and may be a laminated film.

The 3 rd electrode 24 is provided on the 5 th insulating film 95 and connected to the drain electrode 63 through the contact hole H2. In this manner, the 1 st electrode 23 and the 3 rd electrode 24 connect the anode of the light emitting element 3 and the drain electrode 63 of the 1 st transistor Tr 1. The 4 th electrode 25 and the 3 rd electrode 24 are provided on the same layer, and are connected to the source electrode 62 through a contact hole H4.

A planarization film 27 is provided on the 7 th insulating film 97. The planarization film 27 is provided from the display area AA to the peripheral area GA. The planarization film 27 is a light-transmitting organic insulating film, and is made of a resin material such as a silicone resin, an epoxy resin, an acrylic resin, or a polyimide resin. Further, a cover portion 5 made of a member that transmits light, such as glass, is provided on the planarization film 27.

Fig. 4 is an explanatory view for schematically explaining the connection of the array substrate and the light emitting element. As shown in fig. 4, the light-emitting element 3 is formed by stacking a buffer layer 32, an n-type cladding layer 33, an active layer 34, a p-type cladding layer 35, and an anode electrode 36 in this order on a transparent substrate 31. The light-emitting element 3 is mounted such that the translucent substrate 31 is on the upper side and the anode electrode 36 is on the lower side. In the n-type cladding layer 33, a region exposed from the active layer 34 is provided on the side opposite to the 2 nd electrode 22. A cathode electrode 38 is provided in this region.

The anode electrode 36 is formed of a material having metallic luster that reflects light from the light-emitting layer. The anode electrode 36 is connected to the 1 st electrode 23 via a bonding conductor 39A. The cathode electrode 38 is connected to the 2 nd electrode 22 via a bonding conductor 39B.

In the light-emitting element 3, the p-type cladding layer 35 and the n-type cladding layer 33 are not directly joined, and another layer (active layer 34) is introduced therebetween. This allows carriers such as electrons and holes to be concentrated in the active layer 34, and recombination (light emission) can be efficiently achieved. For high efficiency, a multiple quantum well structure (MQW structure) in which an energy well layer composed of a plurality of atomic layers and an energy barrier layer are periodically stacked may be used as the active layer 34. The light-emitting element 3 has a light-emitting layer in which an n-type clad layer, an active layer, and a p-type clad layer are stacked in this order, and for example, a compound semiconductor such as gallium nitride (GaN) or aluminum indium phosphide (AlInP) is used. As shown in fig. 4, the light-emitting element 3 has a so-called front-side-down structure in which a cathode electrode 38 connected to the n-type cladding layer and an anode electrode 36 connected to the p-type cladding layer are provided on the lower side. The light emitting element 3 may be an LED chip having another structure.

Fig. 5 is a plan view schematically illustrating the 1 st electrode and the 2 nd electrode in embodiment 1. As shown in fig. 5, the array substrate 2 has a 2 nd electrode 22 and a 1 st electrode 23. The 7 th insulating film 97 covers the 1 st electrode 23 and the 2 nd electrode 22, and a part of the 1 st electrode 23 and the 2 nd electrode 22 is exposed in the opening portion of the 7 th insulating film 97. As shown in fig. 5, the 2 nd electrode 22 has two opening portions of the 7 th insulating film 97. In the 1 st electrode 23, regions overlapping with the openings of the two 7 th insulating films 97 are the 1 st region 23A and the 2 nd region 23B. The 2 nd electrode 22 also has two opening portions of the 7 th insulating film 97. In the 2 nd electrode 22, the regions overlapping the opening portions of the two 7 th insulating films 97 are the 3 rd region 22A and the 4 th region 22B.

The 2 nd electrode 22 is provided on the upper surface of the array substrate 2 on which the light emitting element 3 is mounted. The 2 nd electrode 22 is provided on the 1 st surface of the 6 th insulating film 96, and is electrically connected to the cathode wiring 26 (see fig. 1) provided in the peripheral region GA via a wiring 26A shown in fig. 5. As shown in fig. 4, the 2 nd electrode 22 is connected to the cathode electrode 38 of the light-emitting element 3 via a bonding conductor 39B.

The 1 st electrode 23 is provided on the upper surface of the array substrate 2 on which the light emitting element 3 is mounted. The 2 nd electrode 22 is provided on the 1 st surface of the 6 th insulating film 96. As shown in fig. 3, the 1 st electrode 23 is connected to the 3 rd electrode 24 via a contact hole H7. The 1 st electrode 23 is connected to the anode electrode 36 of the light-emitting element 3 via a bonding conductor 39A.

The bonding conductor 39A is a metal containing Sn as a main component, for example. The 1 st electrode 23 is a metal laminate, for example, in which Al and Ti are laminated in this order. The bonding conductor 39A has a melting point lower than that of Al which is a material of the surface of the 1 st electrode 23. Similarly, the bonding conductor 39B is a metal containing Sn as a main component, for example. The 2 nd electrode 22 is a metal laminate, for example, in which Al and Ti are laminated in this order. The bonding conductor 39B has a melting point lower than that of Al which is a material of the surface of the 2 nd electrode 22.

As shown in fig. 5, the area of the 1 st region 23A is smaller than the area of the lower side of the light emitting element 3. Here, the area of the lower side of the light emitting element 3 is 3w × 3h obtained by multiplying the length 3w of the 1 st direction Dx by the length 3h of the 2 nd direction Dy. The area of the 2 nd region 23B is equal to or larger than the area of the 1 st region 23A. The area of the 1 st electrode 23 provided with the 1 st region 23A is 23w × 23h obtained by multiplying the length 23w of the 1 st direction Dx by the length 23h of the 2 nd direction Dy. Therefore, the area of the 1 st region 23A is smaller than 23w × 23 h.

The area of the 2 nd region 23B is more preferably equal to or larger than the area under the light emitting element 3. The area of the 1 st electrode 23 provided with the 2 nd region 23B is 23Bw × 23Bh obtained by multiplying the length 23Bw of Dx in the 1 st direction by the length 23Bh of Dy in the 2 nd direction. Therefore, the area of the 2 nd region 23B is smaller than 23Bw × 23 Bh.

Since the material of the surface of the 2 nd region 23B has metallic luster, the 2 nd region 23B also functions as a light reflecting layer. This improves the viewing angle characteristics of the display device 1.

As shown in fig. 5, the area of the 3 rd region 22A is smaller than the lower side area of the light emitting element 3. The area of the 4 th region 22B is equal to or larger than the area of the 3 rd region 22A. The area of the 2 nd electrode 22 provided with the 3 rd region 22A is 23w × 23h obtained by multiplying the length 23w of Dx in the 1 st direction by the length 23h of Dy in the 2 nd direction. Therefore, the area of the 3 rd region 22A is smaller than 23Bw × 23 Bh.

The area of the 4 th region 22B is more preferably equal to or larger than the area under the light-emitting element 3. The area of the 2 nd electrode 22 provided with the 4 th region 22B is larger than 22Bw x 22Bh obtained by multiplying the length 22Bw of the Dx in the 1 st direction by the length 22Bh of Dy in the 2 nd direction. Therefore, the area of the 4 th region 22B is smaller than 22Bw × 22 Bh.

Since the material of the surface of the 4 th region 22B has metallic luster, the 4 th region 22B also functions as a light reflecting layer. This improves the viewing angle characteristics of the display device 1.

Next, a method for manufacturing the display device 1 will be described. Fig. 6 is an explanatory view for explaining a part of the steps of the manufacturing method in embodiment 1. Fig. 7 is an explanatory diagram showing a configuration of a manufacturing apparatus of a display device according to embodiment 1. After the substrate preparation step of preparing the array substrate 2, as shown in fig. 6, a bonding step of bonding the light emitting elements 3 to the array substrate 2 prepared in advance is performed. In the bonding process, the pickup tool 200 as the holding member has an attracting force or an adhesive force, and holds the light emitting element 3. The pickup tool 200 conveys the light emitting element 3 above a predetermined pixel Pix (see fig. 1) of the array substrate 2. Thereby, the light emitting element 3 is mounted on the array substrate 2 (step ST 11).

The manufacturing system 100 shown in fig. 7 performs a bonding process, a lighting inspection process, and a repair process of the display device 1 including the array substrate 2 and the plurality of light emitting elements 3 arranged on the array substrate 2. As shown in fig. 7, the manufacturing system 100 includes a lighting inspection apparatus 8, an inspection control circuit 101, a light detection apparatus 102, an image processing circuit 103, an inspection drive circuit 104, and a laser apparatus 105.

As shown in fig. 6, the laser device 105 shown in fig. 7 irradiates the light-emitting element 3 with the laser light L1 (step ST 12). The bonding conductor 39A between the anode electrode 36 and the 1 st electrode 23 is melted by the laser light L1, and the anode electrode 36 and the 1 st electrode 23 are bonded via the bonding conductor 39A. The bonding conductor 39B between the cathode electrode 38 and the 2 nd electrode 22 is melted by the laser light L1, and the cathode electrode 38 and the 2 nd electrode 22 are bonded via the bonding conductor 39B.

Next, the manufacturing system 100 performs lighting inspection of the plurality of light emitting elements 3. As shown in fig. 7, the inspection control circuit 101 is a circuit for controlling the lighting inspection of the plurality of light emitting elements 3. The inspection control circuit 101 controls an inspection drive circuit 104 for lighting the plurality of light emitting elements 3.

The lighting inspection device 8 is an inspection board for performing lighting inspection of the plurality of light emitting elements 3. The inspection electrode 82 of the lighting inspection apparatus 8 is in contact with the 2 nd electrode 22, and thereby electrically connected to the cathode electrode 38 of the light emitting element 3.

Specifically, the manufacturing system 100 brings the inspection electrode 82 of the lighting inspection apparatus 8 into contact with the 2 nd electrode 22 of the light-emitting element 3 (step ST 12). As shown in fig. 7, the inspection substrate 81 is disposed to face the array substrate 2 with the plurality of light-emitting elements 3 interposed therebetween. The inspection electrode 82 is provided on the surface of the inspection substrate 81 facing the array substrate 2, and is electrically connected to the light-emitting element 3.

The inspection substrate 81 is a light-transmitting insulating substrate, and is, for example, a glass substrate, a quartz substrate, or a flexible substrate made of an acrylic resin, an epoxy resin, a polyimide resin, or a polyethylene terephthalate (PET) resin. Thus, even when the lighting inspection device 8 is disposed to overlap the plurality of light-emitting elements 3, the light 3L emitted from the plurality of light-emitting elements 3 passes through the lighting inspection device 8 and reaches the photodetection device 102. The inspection electrode 82 is made of a conductive material.

By moving the lighting inspection apparatus 8 toward the array substrate 2, the 2 nd electrode 22 of the light emitting element 3 is brought into contact with the inspection electrode 82.

The inspection drive circuit 104 supplies the anode power supply potential PVDD to the array substrate 2 and the cathode power supply potential PVSS to the lighting inspection apparatus 8 based on a control signal from the inspection control circuit 101. A current corresponding to the potential difference between the anode power supply potential PVDD and the cathode power supply potential PVSS flows through the light emitting element 3, and the light emitting element 3 emits light. The inspection drive circuit 104 may supply a potential for lighting the light emitting element 3 as an inspection drive signal, or may supply a potential different from the anode power supply potential PVDD and the cathode power supply potential PVSS at the time of display in the display device 1.

The light detection device 102 detects the light 3L emitted from each of the plurality of light-emitting elements 3. The light detection device 102 is an image sensor having an image pickup device such as a CCD. The image processing circuit 103 receives a detection signal (image data) from the photodetection device 102 and performs image processing, thereby analyzing the lighting state (for example, luminance) of each of the plurality of light-emitting elements 3. The image processing circuit 103 outputs information on the lighting states of the plurality of light emitting elements 3 to the inspection control circuit 101.

The inspection control circuit 101 determines the lighting state of each of the plurality of light emitting elements 3 based on information from the image processing circuit 103. For example, if the luminance of the light 3L emitted from the light emitting element 3 is within a predetermined range, the inspection control circuit 101 determines that the lighting state of the light emitting element 3 is good. The light emitting element 3 in a good lighting state is excluded from the object of repair. The inspection control circuit 101 determines that the light emitting element 3 is in the unlit state when the luminance of the light 3L emitted from the light emitting element 3 is smaller than a reference value. The inspection control circuit 101 calculates the ratio of the number of light-emitting elements 3 in the non-lit state to the number of all light-emitting elements 3 as the connection failure rate. The inspection control circuit 101 calculates the positions of the light emitting element 3 in the lit state and the light emitting element 3 in the unlit state.

The light emitting element 3 determined to be in the unlit state is subjected to predetermined repair by the manufacturing system 100. In the repairing step, since the position of the light emitting element 3 is prevented from being changed by melting of the bonding conductor 39A, the pickup tool 200 holds the light emitting element 3 by suction or suction. Then, the laser apparatus 105 irradiates the 2 nd region 23B and the 4 th region 22B with the laser light L (step ST 13).

When the 2 nd region 23B of the 1 st electrode 23 irradiated with the laser light L generates heat and the heat is transferred to the 1 st region 23A of the 1 st electrode 23, the bonding conductor 39A melts. Similarly, when the 4 th region 22B of the 2 nd electrode 22 irradiated with the laser light L generates heat and heat is transferred to the 3 rd region 22A of the 2 nd electrode 22, the bonding conductor 39B melts.

In a state where the bonding conductor 39A and the bonding conductor 39B are melted, the pickup tool 200 peels the light emitting element 3 from the array substrate 2. Then, the 1 ST electrode 23 is separated from the anode electrode 36, and the 2 nd electrode 22 is separated from the cathode electrode 38 (step ST 14). As a result, even when the light emitting element 3 is detached from the array substrate 2 by the pick-up tool 200, damage to the 1 st electrode 23 and the 2 nd electrode 22 is suppressed.

The pickup tool 200 conveys another light emitting element 3N above the pixel Pix (see fig. 1) from which the light emitting element 3 is detached. Thereby, the light emitting element 3N is mounted on the array substrate 2 (step ST 15). The volume of the conductor for bonding 39A and the conductor for bonding 39B is reduced by repair. Therefore, the bonding conductor 39C made of the same material as the bonding conductor 39A is bonded to the anode 36 in advance. Similarly, a bonding conductor 39D made of the same material as the bonding conductor 39B is bonded to the cathode 38 in advance.

Next, the laser apparatus 105 irradiates the 2 nd region 23B and the 4 th region 22B with the laser light L (step ST 16).

When the 2 nd region 23B of the 1 st electrode 23 irradiated with the laser light L generates heat and heat is transferred to the 1 st region 23A of the 1 st electrode 23, the bonding conductor 39A and the bonding conductor 39C are melted to become a bonding conductor 39E. Similarly, when the 4 th region 22B of the 2 nd electrode 22 irradiated with the laser light L generates heat and heat is transferred to the 3 rd region 22A of the 2 nd electrode 22, the bonding conductor 39B and the bonding conductor 39D are melted to become the bonding conductor 39F.

The anode electrode 36 and the 1 st electrode 23 are joined via a joining conductor 39E. The cathode 38 and the 2 nd electrode 22 are joined via a joining conductor 39F. As a result, the light emitting element 3N is bonded to the array substrate 2 (step ST 17). If the lighting state of the light emitting element 3N is good in the lighting inspection step, the light emitting element is excluded from the object of the repair step. When it is determined that the light emitting element 3N is in the non-lighting state in the lighting inspection step, the light emitting element 3N is repaired again.

Fig. 8 is an explanatory diagram for explaining an influence of irradiation with laser light. As shown in fig. 4 and 8, the heating mark LA remains in the 2 nd area 23B irradiated with the laser beam L1. The heat trace LA can form fine irregularities on the surface compared to the surface F of the 2 nd region 23B not receiving the laser beam, and the color of the reflected light is different from that of the surface F. The heating mark LA formed in the 4 th region 22B is also in the same state.

As described above, the display device 1 includes the array substrate 2 and the plurality of light emitting elements 3 as the inorganic light emitting diodes bonded to the array substrate 2. The array substrate 2 includes a substrate 21, a 5 th insulating film 95 and a 6 th insulating film 96 laminated on the substrate 21, and a plurality of 1 st electrodes 23 provided on the 6 th insulating film 96 and electrically connected to the anode electrodes 36 of the light-emitting elements 3.

The 1 st electrode 23 has a 1 st region 23A and a 2 nd region 23B located at a position different from the 1 st region 23A. The 1 st electrode 23 is joined to the anode electrode 36 via a joining conductor 39A. The 2 nd region 23B exists in the display region AA for each pixel Pix, and thus, a plurality of the 2 nd regions 23B exist in the array substrate 2. When the light emitting element 3 is bonded to the array substrate 2 without a repair process because the lighting state of the light emitting element 3 is good, the heating mark LA does not remain in the 2 nd region 23B. When the light emitting element 3N is bonded to the array substrate 2 after the repair process, at least one 2 nd region 23B having the heating mark LA is present among the plurality of 2 nd regions 23B included in the display region AA.

The 2 nd electrode 22 has a 3 rd region 22A and a 4 th region 22B located at a position different from the 3 rd region 22A. The 2 nd electrode 22 is joined to the cathode electrode 38 via a joining conductor 39B. Since the 4 th region 22B exists in the display region AA for each pixel Pix, a plurality of the 4 th regions 22B exist in the array substrate 2. When the light emitting element 3 is bonded to the array substrate 2 without a repair process because the lighting state of the light emitting element 3 is good, the heating mark LA does not remain in the 4 th region 22B. When the light emitting element 3N is bonded to the array substrate 2 after the repair process, at least one 4 th region 22B having the heating mark LA is present among the plurality of 4 th regions 22B included in the display region AA.

Accordingly, even if the pickup tool 200 peels the light-emitting element 3 off the array substrate 2 in a state where the light-emitting element 3 that needs to be replaced is bonded to the array substrate 2, the bonding conductors 39A and 39B are melted, and therefore the 1 st electrode 23 and the 2 nd electrode 22 of the array substrate 2 are less likely to be damaged. Therefore, the display device can be repaired, and the manufacturing yield can be improved.

As shown in fig. 3, the 3 rd electrode 24 is located between the substrate 21 and the 1 st electrode 23. The 3 rd electrode 24 is embedded in the 5 th insulating film 95 and the 6 th insulating film 96. The 3 rd electrode 24 is electrically connected to the drain electrode 63 of the 1 st transistor Tr1 that drives the light emitting element 3. The 1 st electrode 23 is connected to the 3 rd electrode 24 via a contact hole H7. If the 3 rd electrode 24 is made of an Oxide conductor such as ITO, IZO (Indium Zinc Oxide), SnO, or the like, the 1 st transistor Tr1 can be protected from heat from the laser beam. This is because the oxide conductor has a lower heat transfer efficiency than metals such as Al.

(embodiment mode 2)

Fig. 9 is a sectional view of the display device according to embodiment 2. The cross section of fig. 9 is a cross section taken in the direction of the arrow on the line III-III' of fig. 1, as in embodiment 1. Fig. 10 is a plan view schematically illustrating a 1 st electrode in embodiment 2. Fig. 11 is an explanatory view for explaining a part of the steps of the manufacturing method in embodiment 2. Fig. 12 is an explanatory diagram showing a configuration of a manufacturing apparatus of a display device according to embodiment 2. The same components as those described in embodiment 1 are denoted by the same reference numerals, and redundant description thereof is omitted. The light-emitting element 3A of embodiment 2 is different from the light-emitting element 3 of embodiment 1 in that the cathode electrode 38 of the light-emitting element 3A is located above the main body of the light-emitting element 3A.

As shown in fig. 9, the 2 nd electrode 22 of embodiment 2 is electrically connected to the cathode electrode 38 of the light-emitting element 3A so as to cover the light-emitting element 3A and the planarization film 27. The 2 nd electrode 22 is provided across the upper surface of the planarization film 27 and the upper surface of the cathode electrode 38. The 2 nd electrode 22 supplies a cathode power supply potential PVSS to the cathode electrode 38. For the 2 nd electrode 22, a light-transmitting conductive material such as ITO (Indium Tin Oxide) is used. This enables light emitted from the light emitting element 3A to be efficiently extracted to the outside.

The 2 nd electrode 22 is provided continuously from the display area AA to the peripheral area GA, and is connected to the cathode line 26 at the bottom of the contact hole H1. Specifically, the contact hole H1 is provided in the peripheral region GA so as to penetrate the planarization film 27 and the 5 th insulating film 95, and the cathode line 26 is provided on the bottom surface of the contact hole H1. The cathode wiring 26 is provided on the 4 th insulating film 94. That is, the cathode line 26 is formed of the same material as the source electrode 62 and the drain electrode 63 in the same layer.

As shown in fig. 9, the array substrate 2 has the 1 st electrode 23. The 7 th insulating film 97 covers the 1 st electrode 23, and a part of the 1 st electrode 23 is exposed at the opening of the 7 th insulating film 97. As shown in fig. 10, the 1 st electrode 23 has regions overlapping the openings of the two 7 th insulating films 97 as the 1 st region 23A and the 2 nd region 23B.

As shown in fig. 10, the area of the 1 st region 23A is smaller than the area of the lower side of the light emitting element 3A. Here, the area of the lower side of the light emitting element 3A is 3w × 3h obtained by multiplying the length 3w of the 1 st direction Dx by the length 3h of the 2 nd direction Dy. The area of the 2 nd region 23B is equal to or larger than the area of the 1 st region 23A. The area of the 1 st electrode 23 provided with the 1 st region 23A is 23w × 23h obtained by multiplying the length 23w of the 1 st direction Dx by the length 23h of the 2 nd direction Dy. Therefore, the area of the 1 st region 23A is smaller than 23w × 23 h.

The area of the 2 nd region 23B is more preferably equal to or larger than the area under the light-emitting element 3A. The area of the 1 st electrode 23 provided with the 2 nd region 23B is 23Bw × 23Bh obtained by multiplying the length 23Bw of Dx in the 1 st direction by the length 23Bh of Dy in the 2 nd direction. Therefore, the area of the 2 nd region 23B is smaller than 23Bw × 23 Bh.

Next, a method for manufacturing the display device 1 will be described. After the substrate preparation step of preparing the array substrate 2, as shown in fig. 11, a bonding step of bonding the light emitting elements 3 to the array substrate 2 prepared in advance is performed. In the bonding process, the pickup tool 200 as the holding member has an attracting force or an adhesive force, and holds the light emitting element 3A. The pickup tool 200 conveys the light emitting element 3A above a predetermined pixel Pix (see fig. 1) of the array substrate 2. Thereby, the light emitting element 3A is mounted on the array substrate 2 (step ST 21).

The manufacturing system 100 shown in fig. 12 performs a bonding process, a lighting inspection process, and a repair process of the display device 1 including the array substrate 2 and the plurality of light emitting elements 3A arranged on the array substrate 2. As shown in fig. 12, the manufacturing system 100 includes a lighting inspection apparatus 8, an inspection control circuit 101, a light detection apparatus 102, an image processing circuit 103, an inspection drive circuit 104, and a laser apparatus 105.

As shown in fig. 11, the laser device 105 shown in fig. 12 irradiates the light-emitting element 3A with the laser light L1 (step ST 22). According to the laser lift-off technique, the laser device 105 peels off the transparent substrate 31 from the light emitting element 3A. The bonding conductor 39A between the anode electrode 36 and the 1 st electrode 23 is melted by the laser light L1, and the anode electrode 36 and the 1 st electrode 23 are bonded via the bonding conductor 39A.

Next, the manufacturing system 100 performs lighting inspection of the plurality of light emitting elements 3A. As shown in fig. 12, the inspection control circuit 101 is a circuit for controlling lighting inspection of the plurality of light emitting elements 3A. The inspection control circuit 101 controls an inspection drive circuit 104 for lighting the plurality of light emitting elements 3A.

The lighting inspection device 8 is an inspection board for performing lighting inspection of the plurality of light emitting elements 3A. The inspection electrode 82 of the lighting inspection apparatus 8 is in contact with the 2 nd electrode 22, and thereby electrically connected to the cathode electrode 38 of the light emitting element 3A.

Specifically, the manufacturing system 100 brings the inspection electrode 82 of the lighting inspection apparatus 8 into contact with the 2 nd electrode 22 of the light-emitting element 3A (step ST 23). As shown in fig. 12, the inspection substrate 81 is disposed to face the array substrate 2 with the plurality of light emitting elements 3A interposed therebetween. The inspection electrode 82 is provided on the surface of the inspection substrate 81 facing the array substrate 2, and is electrically connected to the light emitting element 3A.

The inspection substrate 81 is an insulating substrate having light transmittance, and is, for example, a glass substrate, a quartz substrate, or a flexible substrate made of an acrylic resin, an epoxy resin, a polyimide resin, or a polyethylene terephthalate (PET) resin. Thus, even when the lighting inspection apparatus 8 is disposed to overlap the plurality of light-emitting elements 3A, the light 3L emitted from the plurality of light-emitting elements 3A passes through the lighting inspection apparatus 8 and reaches the photodetection apparatus 102. The inspection electrode 82 is made of a light-transmitting conductive material such as ITO.

By moving the lighting inspection apparatus 8 toward the array substrate 2, the 2 nd electrode 22 of the light emitting element 3A is brought into contact with the inspection electrode 82.

The inspection drive circuit 104 supplies the anode power supply potential PVDD to the array substrate 2 and the cathode power supply potential PVSS to the lighting inspection apparatus 8 based on a control signal from the inspection control circuit 101. A current corresponding to the potential difference between the anode power supply potential PVDD and the cathode power supply potential PVSS flows through the light emitting element 3A, and the light emitting element 3A emits light. The inspection drive circuit 104 may supply a potential for lighting the light emitting element 3A as an inspection drive signal, or may supply a potential different from the anode power supply potential PVDD and the cathode power supply potential PVSS at the time of display in the display device 1.

The light detection device 102 detects the light 3L emitted from each of the plurality of light-emitting elements 3A. The light detection device 102 is an image sensor having an image pickup device such as a CCD. The image processing circuit 103 receives a detection signal (image data) from the photodetection device 102 and performs image processing, thereby analyzing the lighting state (for example, luminance) of each of the plurality of light emitting elements 3A. The image processing circuit 103 outputs information on the lighting states of the plurality of light emitting elements 3A to the inspection control circuit 101.

The inspection control circuit 101 determines the lighting state of each of the plurality of light emitting elements 3A based on information from the image processing circuit 103. For example, if the luminance of the light 3L emitted from the light emitting element 3A is within a predetermined range, the inspection control circuit 101 determines that the lighting state of the light emitting element 3A is good. The light emitting element 3A in a good lighting state is excluded from the object of repair. When the luminance of the light 3L emitted from the light-emitting element 3A is smaller than the reference value, the inspection control circuit 101 determines that the light-emitting element 3A is in the non-lighting state. The inspection control circuit 101 calculates the ratio of the number of the light-emitting elements 3A in the unlit state to the number of all the light-emitting elements 3A as the connection failure rate. The inspection control circuit 101 calculates the positions of the light emitting element 3A in the lit state and the light emitting element 3A in the unlit state.

The light emitting element 3A determined to be in the unlit state is subjected to a predetermined repair by the manufacturing system 100. In the repairing step, since the position of the light emitting element 3A is prevented from being changed by melting of the bonding conductor 39A, the pickup tool 200 holds the light emitting element 3A by suction or suction. Then, the laser apparatus 105 irradiates the 2 nd area 23B with the laser light L (step ST 24).

When the 2 nd region 23B of the 1 st electrode 23 irradiated with the laser light L generates heat and the heat is transferred to the 1 st region 23A of the 1 st electrode 23, the bonding conductor 39A melts.

In a state where the bonding conductor 39A is being melted, the pickup tool 200 peels the light emitting element 3A from the array substrate 2. Then, the 1 ST electrode 23 is separated from the anode electrode 36 (step ST 25). As a result, even if the pickup tool 200 detaches the light emitting element 3A from the array substrate 2, damage to the 1 st electrode 23 is suppressed.

The pickup tool 200 conveys another light emitting element 3AN above the pixel Pix (see fig. 1) from which the light emitting element 3A is detached. Similarly to step ST22, the laser device 105 shown in fig. 12 irradiates the light-emitting element 3AN with the laser light L1. Thereby, the light emitting element 3AN is mounted on the array substrate 2 (step ST 26). Since the volume of the conductor for bonding 39A is reduced by the repair, the conductor for bonding 39C made of the same material as the conductor for bonding 39A is bonded to the anode 36 in advance. The laser light L1 is irradiated to melt the joining conductor 39A and the joining conductor 39C, thereby forming a joining conductor 39E. As a result, the anode electrode 36 and the 1 st electrode 23 are bonded via the bonding conductor 39E. The light emitting element 3AN is bonded to the array substrate 2. If the lighting state of the light emitting element 3AN is good in the lighting inspection step, the light emitting element 3AN is excluded from the repair step. When it is determined that the light emitting element 3AN is in the non-lighting state in the lighting inspection process, the light emitting element 3AN is repaired again.

In addition, as in embodiment 1, the heating mark LA remains in the 2 nd region 23B irradiated with the laser beam L1 shown in fig. 15. The heat trace LA forms fine irregularities on the surface compared to the surface F of the 2 nd region 23B not irradiated with the laser light, and the color of the reflected light is different from that of the surface F.

As described above, the display device 1 includes the array substrate 2 and the plurality of light emitting elements 3A as the inorganic light emitting diodes bonded to the array substrate 2. The array substrate 2 includes a substrate 21, a 5 th insulating film 95 and a 6 th insulating film 96 laminated on the substrate 21, and a plurality of 1 st electrodes 23 provided on the 6 th insulating film 96 and electrically connected to the anode electrodes 36 of the light-emitting elements 3A.

The 1 st electrode 23 has a 1 st region 23A and a 2 nd region 23B located at a position different from the 1 st region 23A. The 1 st electrode 23 is joined to the anode electrode 36 via a joining conductor 39A. The 2 nd region 23B exists in the display region AA for each pixel Pix, and thus, a plurality of the 2 nd regions 23B exist in the array substrate 2. When the light emitting element 3A is bonded to the array substrate 2 without a repair process because the lighting state of the light emitting element 3A is good, the heating mark LA does not remain in the 2 nd region 23B. When the light emitting element 3AN is bonded to the array substrate 2 after the repair process, at least one 2 nd region 23B having the heating mark LA is present among the plurality of 2 nd regions 23B included in the display region AA.

Thus, in a state where the light emitting element 3A to be replaced is bonded to the array substrate 2, even if the pickup tool 200 peels the light emitting element 3A from the array substrate 2, the bonding conductor 39A is melted, and therefore, the 1 st electrode 23 of the array substrate 2 is less likely to be damaged. Therefore, the display device 1 can be repaired, and the manufacturing yield can be improved.

(embodiment mode 3)

Fig. 13 is a sectional view of the display device according to embodiment 3. The cross section of fig. 13 is a cross section taken in the direction of the arrow on the line III-III' of fig. 1, as in embodiment 1. The same components as those described in the above embodiment are denoted by the same reference numerals, and redundant description thereof is omitted. The array substrate 2 according to embodiment 3 is different from the array substrate 2 according to embodiment 2 in that the 2 nd region 23B of the cathode electrode 38 is located above the 1 st region 23A.

An 8 th insulating film 98 is formed on the 6 th insulating film 96. The 8 th insulating film 98 is provided on the 6 th insulating film 96, and a convex portion is formed to protrude from the 1 st region 23A. The 8 th insulating film 98 is a light-transmitting organic insulating film, and a resin material such as a silicone resin, an epoxy resin, an acrylic resin, or a polyimide resin is used. Here, the 8 th insulating film 98 may be an inorganic insulating film formed to be thick as long as it has a certain height.

The 1 st electrode 23 of embodiment 3 is provided on the 6 th insulating film 96 and the 8 th insulating film 98. The 1 st region 23A is located on the 6 th insulating film 96, and the 2 nd region 23B is located on the 8 th insulating film 98. Therefore, the 1 st region 23A is located closer to the substrate 21 than the 2 nd region 23B.

The 2 nd area 23B is located above the 1 st area 23A, and therefore is less likely to be a shadow of the picking tool 200. Further, since the 2 nd region 23B is located above the 1 st region 23A, the laser device 105 can easily irradiate the 1 st region 23A with the laser light L1.

(embodiment mode 4)

Fig. 14 is a sectional view of the display device according to embodiment 4. The cross section of fig. 14 is a cross section taken in the direction of the arrow on the line III-III' of fig. 1, as in embodiment 1. Fig. 15 is a plan view schematically illustrating a 1 st electrode in embodiment 4. The same components as those described in the present embodiment are denoted by the same reference numerals, and redundant description thereof is omitted. The array substrate 2 according to embodiment 4 is different from the array substrate 2 according to embodiment 2 in that the 2 nd region 23B of the cathode electrode 38 is located above the 1 st region 23A. The array substrate 2 according to embodiment 4 is different from the array substrate 2 according to embodiment 3 in that the 8 th insulating film 98 is formed in a ring shape in a plan view.

An 8 th insulating film 98 is formed on the 6 th insulating film 96. The 8 th insulating film 98 is provided on the 6 th insulating film 96, and a convex portion protruding from the position of the 1 st region 23A is formed. The projection formed by the 8 th insulating film 98 surrounds the 1 st region 23A where the light emitting element 3A is arranged. Thus, even if the bonding conductor 39A melts and spreads during bonding, the projection formed by the 8 th insulating film 98 serves as a bank to suppress the diffusion of the bonding conductor 39A. As a result, accidental short circuits and the like can be suppressed.

(embodiment 5)

Fig. 16 is a sectional view of the display device according to embodiment 5. The cross section of fig. 16 is a cross section taken in the direction of the arrow on the line III-III' of fig. 1, as in embodiment 1. The same components as those described in the above embodiment are denoted by the same reference numerals

And duplicate descriptions are omitted. In the 1 st region 23A of the 1 st electrode 23 and the 1 st electrode 23

The 2 nd region 23B is separated, and the 1 st electrode 23 of embodiment 5 is different from the 1 st electrode 23 of embodiment 2.

As shown in fig. 16, the 1 st region 23A of the 1 st electrode 23 of embodiment 5 is separated from the 2 nd region 23B of the 1 st electrode 23. The slit SP between the 1 st region 23A of the 1 st electrode 23 and the 2 nd region 23B of the 1 st electrode 23 is covered with a 7 th insulating film 97.

The 2 nd region 23B of the 1 st electrode 23 is electrically connected to the 3 rd electrode 24 via the contact hole H9.

In the repairing step, the 2 nd region 23B of the 1 st electrode 23 is irradiated with the laser light L, as in embodiment 2. The 2 nd region 23B of the 1 st electrode 23 irradiated with the laser light L generates heat, and the heat is transferred to the 3 rd electrode 24 through the contact hole H9. When the heat transferred to the 3 rd electrode 24 is conducted to the 1 st region 23A of the 1 st electrode 23 through the contact hole H7, the bonding conductor 39A melts.

The 3 rd electrode 24 is embedded in the 5 th insulating film 95 and the 6 th insulating film 96. Since the 5 th insulating film 95 is an organic insulating film as described above, it has higher heat insulating property than an inorganic insulating film. Therefore, the melting time of the bonding conductor 39A in the repairing step becomes long. As a result, the possibility that the pickup tool 200 peels the light emitting element 3A from the array substrate 2 in a solidified state after the bonding conductor 39A is once melted is reduced. Further, even if the pickup tool 200 detaches the light emitting element 3A from the array substrate 2, damage of the 1 st electrode 23 is suppressed.

The preferred embodiments are described above, but the present disclosure is not limited to such embodiments. The disclosure of the embodiments is merely an example, and various modifications can be made without departing from the scope of the present disclosure. It is needless to say that appropriate modifications made within a range not departing from the gist of the present disclosure also belong to the technical scope of the present disclosure.