JP2024010383A - Manufacturing method for display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve performance of a display device.

SOLUTION: A manufacturing method for a display device includes a step of aligning a substrate SS1 (first substrate) on which a plurality of LED elements 20 is arranged in a matrix state and a transfer substrate (second substrate). In the aligning step, the substrate SS1 and the second substrate are aligned on the basis of positional information of a plurality of alignment marks AM provided on the substrate SS1. The alignment marks AM are present in a region where the LED elements 20 are arranged. A separation distance D1 between the LED elements 20 that are adjacent to each other through each alignment mark AM is larger than a separation distance D2 of the LED elements 20 that are adjacent to each other not through one alignment mark AM.

SELECTED DRAWING: Figure 7

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a technology for manufacturing display devices.

As a display device, there is an LED (Light Emitting Diode) display device in which light emitting diode elements, which are self-luminous elements, are arranged in a matrix on a substrate. For example, US Patent Application Publication No. 2019/0096774 Patent Document 1 describes that alignment marks are formed on the template when transferring a plurality of microdevices (LEDs) from the template to the receiver substrate. ing. Japanese Patent Publication No. 2019-511838 (Patent Document 2) describes a method for transferring three types of LED elements from a growth substrate to a target substrate.

US Patent Application Publication No. 2019/0096774 Special table 2019-511838 publication

In the case of an LED display device, a large number of LED elements are mounted on an array substrate. In the process of mounting the LED elements from the sapphire substrate on which they are formed to the array substrate (sometimes called a backplane), the LED elements are transferred from the sapphire substrate to the transfer substrate, and then retransferred from the transfer substrate to the array substrate. There are ways to do this. In this way, when transferring a plurality of LED elements, it is necessary to align the transfer source substrate and the transfer destination substrate with high precision. As a technique for improving the accuracy of alignment, there is a method of using alignment marks.

Here, a suitable position for providing the alignment mark differs depending on the specifications of the display device or the specifications of the display device manufacturing apparatus. However, if alignment marks are formed at different positions depending on the specifications of the display device or the specifications of the display device manufacturing apparatus, the versatility of the sapphire substrate on which the LED elements are formed is reduced.

A method for manufacturing a display device, which is one aspect of the present invention, includes: (a) a first substrate having a first surface on which a plurality of first inorganic light emitting elements are arranged in a matrix; and an adhesive resin. a step of preparing a second substrate having a second surface on which a layer is formed; (b) a step of aligning the first substrate and the second substrate; and (c) the step of (b) After the step, a step of attaching each of the plurality of first inorganic light emitting elements to the adhesive resin layer on the second substrate; (d) After the step (c), attaching the first substrate and the second The method includes the step of separating each of the plurality of first inorganic light emitting elements from the first substrate by increasing the distance from the substrate. In the step (b), the first substrate and the second substrate are aligned based on position information of a plurality of alignment marks provided on the first surface of the first substrate. The plurality of alignment marks are within a region where the plurality of inorganic light emitting elements are arranged, and the distance between adjacent inorganic light emitting elements with each one alignment mark in between is equal to the distance between the one alignment mark. It is wider than the distance between adjacent inorganic light emitting elements without intervening.

FIG. 1 is a plan view showing an example of the configuration of a display device according to an embodiment. FIG. 2 is a circuit diagram showing an example of a configuration of a circuit around a pixel shown in FIG. 1. FIG. 2 is an enlarged cross-sectional view showing an example of a peripheral structure of an LED element arranged in each of a plurality of pixels of the display device shown in FIG. 1. FIG. 4 is an enlarged sectional view showing a modification of the LED element shown in FIG. 3. FIG. FIG. 2 is an explanatory diagram showing a flow of the manufacturing process of the display device shown in FIG. 1. FIG. FIG. 6 is a plan view schematically showing a substrate prepared in the LED holding substrate preparation step shown in FIG. 5; 7 is an enlarged plan view of the vicinity of the alignment mark shown in FIG. 6. FIG. 7 is an explanatory diagram showing an example of a method of providing the alignment mark shown in FIG. 6. FIG. 7 is an enlarged cross-sectional view of each of the plurality of substrates shown in FIG. 6. FIG. 6 is a plan view showing an example of a transfer substrate used in the first transfer step and the second transfer step shown in FIG. 5. FIG. 11 is a cross-sectional view taken along line AA in FIG. 10. FIG. 6 is a cross-sectional view schematically showing an array substrate prepared in the array substrate preparation step shown in FIG. 5. FIG. FIG. 6 is a cross-sectional view schematically showing the positioning step of the first transfer step shown in FIG. 5. FIG. FIG. 6 is a cross-sectional view schematically showing the pasting step of the first transfer step shown in FIG. 5. FIG. 6 is a cross-sectional view schematically showing a state in which a plurality of LED elements are selectively irradiated with a laser in the holding substrate peeling step of the first transfer step shown in FIG. 5. FIG. 6 is a cross-sectional view schematically showing a state where the holding substrate is peeled off from a plurality of LED elements in the holding substrate peeling step of the first transfer step shown in FIG. 5. FIG. 6 is an explanatory diagram showing an example of the second transfer step shown in FIG. 5. FIG. 6 is a cross-sectional view showing an example of the array substrate mounting process shown in FIG. 5. FIG.

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the disclosure is merely an example, and any modifications that can be easily made by those skilled in the art while maintaining the gist of the invention are naturally included within the scope of the present invention. In addition, in order to make the explanation clearer, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual aspect, but these are only examples, and the interpretation of the present invention is It is not limited. In addition, in this specification and each figure, elements similar to those described above with respect to the existing figures are denoted by the same or related numerals, and detailed explanations may be omitted as appropriate.

In the following embodiments, a micro LED display device including a plurality of micro LED elements will be described as an example of a display device using a plurality of inorganic light emitting elements. Micro LED elements have a smaller element size (outer diameter) than general LED elements, so they have the advantage of being able to display high-definition images.

Note that an organic light-emitting diode (OLED) is an example of a light-emitting diode element that is a self-luminous element. The inorganic light emitting diode element (micro LED element) described in the following embodiments is distinguished from the organic light emitting diode element.

<Display device>
First, a configuration example of a micro LED display device, which is a display device of this embodiment, will be described. FIG. 1 is a plan view showing a configuration example of a display device according to an embodiment. In FIG. 1, the boundary between the display area DA and the peripheral area PFA, the control circuit 5, the drive circuit 6, and each of the plurality of pixels PIX are indicated by two-dot chain lines. FIG. 2 is a circuit diagram showing an example of the configuration of a circuit around the pixel shown in FIG.

As shown in FIG. 1, the display device DSP1 of the present embodiment includes a display area DA, a peripheral area PFA surrounding the display area DA in a frame shape, and a plurality of display areas arranged in a matrix within the display area DA. It has a pixel PIX. Further, the display device DSP1 includes a substrate 10, a control circuit 5 formed on the substrate 10, and a drive circuit 6 formed on the substrate 10.

The control circuit 5 is a control circuit that controls driving of the display function of the display device DSP1. For example, the control circuit 5 is a driver IC (Integrated Circuit) mounted on the substrate 10. In the example shown in FIG. 1, the control circuit 5 is arranged along one short side of the four sides of the substrate 10. Further, in the example of the present embodiment, the control circuit 5 includes a signal line drive circuit that drives a video signal line VL (see FIG. 2) connected to a plurality of pixels PIX. However, the position and configuration example of the control circuit 5 is not limited to the example shown in FIG. 1, and there are various modifications. For example, in FIG. 1, a circuit board such as a flexible board is connected to a position shown as the control circuit 5, and the above-described driver IC may be mounted on the circuit board. Further, for example, a signal line drive circuit that drives the video signal line VL may be formed separately from the control circuit 5.

The drive circuit 6 is a circuit that drives the scanning signal line GL among the plurality of pixels PIX. The drive circuit 6 drives the plurality of scanning signal lines GL based on control signals from the control circuit 5. In the example shown in FIG. 1, the drive circuit 6 is arranged along each of two long sides of the four sides of the substrate 10. However, the position and configuration example of the drive circuit 6 is not limited to the example shown in FIG. 1, and there are various modifications. For example, in FIG. 1, a circuit board such as a flexible board may be connected to the position shown as the control circuit 5, and the above-mentioned drive circuit 6 may be mounted on the circuit board.

Next, an example of the circuit configuration of the pixel PIX will be described using FIG. 2. Note that although one pixel PIX is representatively illustrated in FIG. 2, each of the plurality of pixels PIX shown in FIG. 1 includes the same circuit as the pixel PIX shown in FIG. Hereinafter, a circuit including a switch, a capacitor, and an LED element 20 included in the pixel PIX may be referred to as a pixel circuit. The pixel circuit is a voltage signal type circuit that controls the light emitting state of the LED element 20 according to the video signal Vsg supplied from the control circuit 5 (see FIG. 1).

As shown in FIG. 2, the pixel PIX includes an LED element 20. The LED element 20 is the above-mentioned micro light emitting diode. The LED element 20 has an anode electrode 20EA (see FIG. 3 described later) and a cathode electrode 20EK (see FIG. 3 described later). Each of the anode electrode 20EA and cathode electrode 20EK of the LED element 20 is electrically connected to the terminal 30 of the pixel PIX. In the example shown in FIG. 2, the cathode electrode 20EK of the LED element 20 is connected to the terminal 30L, and the anode electrode 20EA of the LED element 20 is connected to the terminal 30H. The terminal 30L is supplied with a potential PVS which is a relatively low fixed potential (low potential), and the terminal 30H is supplied with a potential PVD which is a fixed potential (high potential) higher than the potential supplied to the terminal 30L. Ru.

Pixel PIX includes an output switch BCT, a drive transistor DRT, and a pixel switch SST. The output switch BCT is a transistor that controls the light emission time of the LED element 20 in response to a control signal Gsb supplied from the drive circuit 6. The drive transistor DRT is a transistor that controls the amount of drive current supplied to the anode electrode of the LED element 20 according to the video signal Vsg. The pixel switch SST is a transistor that controls the connection state (on or off state) between the pixel circuit and the video signal line VL in response to the control signal Gss. Further, the drive circuit 6 includes a reset switch RST that controls input of a reset potential. Each of the output switch BCT, drive transistor DRT, pixel switch SST, and reset switch RST is, for example, a thin film transistor. When the pixel switch SST is on, a video signal Vsg is input to the pixel circuit from the video signal line VL.

The drive circuit 6 includes a shift register circuit, an output buffer circuit, etc. (not shown). The drive circuit 6 outputs a pulse based on the horizontal scanning start pulse transmitted from the control circuit 5 (see FIG. 1), and outputs a control signal Gss, a control signal Gsb, and a control signal Gsr.

The plurality of scanning signal lines GL include scanning signal lines GLA, GLB, and a reset wiring GLR. Each of the plurality of scanning signal lines GL extends in the X direction. The scanning signal line GLA is connected to the gate electrode of the output switch BCT. When the control signal Gsb is supplied to the scanning signal line GLA, the output switch BCT is turned on. The scanning signal line GLB is connected to the gate electrode of the pixel switch SST. When the control signal Gss is supplied to the scanning signal line GLB, the pixel switch SST is turned on. The reset wiring GLR is connected between the output switch BCT and the drive transistor DRT and to the drain electrode of the reset switch RST. When a control signal Gsr, which is a reset signal, is supplied to the gate electrode of the reset switch RST, a reset potential is supplied to the reset wiring GLR.

Pixel PIX has a storage capacitor Cs and an auxiliary capacitor Cad. The holding capacitor Cs and the auxiliary capacitor Cad are each capacitors. The holding capacitor Cs is connected between the gate electrode of the drive transistor DRT and the terminal 30H. The auxiliary capacitor Cad is connected between the source electrode of the output switch BCT and the terminal 30H. The auxiliary capacitor Cad is a capacitive element for adjusting the amount of light emitted current, and as a modification, the auxiliary capacitor Cad may not be arranged.

<Peripheral structure of LED element>
Next, the peripheral structure of the LED element arranged in the pixel PIX shown in FIG. 1 will be described. FIG. 3 is an enlarged cross-sectional view showing an example of a peripheral structure of an LED element arranged in each of a plurality of pixels of the display device shown in FIG. FIG. 4 is an enlarged sectional view showing a modification of the LED element shown in FIG. 3.

The array substrate SUB1 shown in FIG. 3 is a substrate including a substrate 10 and a plurality of insulating layers stacked on the substrate 10. The plurality of insulating layers that the array substrate SUB1 has include an inorganic insulating layer 11, an organic insulating layer 12, and an inorganic insulating layer 13. Further, the array substrate SUB1 includes various circuits included in the pixel PIX described using FIG. 2. The substrate 10 has a surface 10f and a surface 10b opposite to the surface 10f. Each of the inorganic insulating layer 11, the organic insulating layer 12, and the inorganic insulating layer 13 is laminated on the surface 10f of the substrate 10.

Each of the inorganic insulating layer 11, the organic insulating layer 12, and the inorganic insulating layer 13 may be a laminated film consisting of a plurality of laminated insulating films. For example, semiconductor layers of thin film transistors forming the output switch BCT, drive transistor DRT, and pixel switch SST shown in FIG. 2 are formed within the inorganic insulating layer 11. Some of the plurality of inorganic insulating films forming the inorganic insulating layer 11 are used as a base layer for forming a thin film transistor, and the other part is used as a gate insulating film of the thin film transistor.

As shown in FIG. 3, the LED elements 20 are mounted on the array substrate SUB1. The LED element 20 includes a surface 20f and a surface 20b opposite to the surface 20f. Furthermore, the LED element 20 includes a plurality of (two in FIG. 3) electrodes 20E arranged on a surface 20f. The plurality of electrodes 20E include an anode electrode 20EA and a cathode electrode 20EK. Anode electrode 20EA is connected to terminal 30H via conductive bonding material 40. Cathode electrode 20EK is connected to terminal 30L via conductive bonding material 40. The conductive bonding material 40 is made of, for example, solder. Although one LED element is illustrated in FIG. 3, a plurality of LED elements are mounted in a matrix on the array substrate SUB1. The display device DSP1 displays images by driving a plurality of LED elements 20 mounted on the array substrate SUB1. The light emitted from the LED element 20 is emitted from, for example, the surface 20b side.

Note that FIG. 3 shows an example of the LED element 20 in which both the anode electrode 20EA and the cathode electrode 20EK are arranged on the surface 20f. However, there are various modifications to the structure of the LED element 20. For example, in the case of the LED element 20M1 shown in FIG. 4, a cathode electrode 20EK is provided on the surface 20b, and an anode electrode 20EA is provided on the surface 20f. When replacing the LED element 20 shown in FIG. 3 with the LED element 20M1 shown in FIG. 4, the terminal 30L (see FIG. 3) connected to the cathode electrode 20EK is provided on the surface 20b of the LED element 20M1.

<Display device manufacturing method>
Next, a method for manufacturing the display device DSP1 shown in FIG. 1 will be described. FIG. 5 is an explanatory diagram showing a flow of the manufacturing process of the display device shown in FIG. 1. In the flow illustrated in FIG. 5, for example, three types of LED elements for red, green, and blue are transferred to three first transfer substrates, and then transferred in order to a second transfer substrate. , a method of mounting on the array substrate via the second transfer substrate will be explained. As shown in FIG. 5, the method for manufacturing a display device according to the present embodiment includes an LED holding substrate preparation step, a first transfer substrate preparation step, a second transfer substrate preparation step, an array substrate preparation step, and a first transfer step. , a second transfer step, and an array substrate mounting step. The details of each step will be explained below.

First, an outline of a method for manufacturing a display device will be explained using FIG. 5. The LED element 20 shown in FIG. 3 is formed on an LED holding substrate (for example, a sapphire substrate) in the LED holding substrate preparation step shown in FIG. The LED elements 20 on the LED holding substrate are transferred from the transfer substrate to the array substrate in the array substrate mounting process through a first transfer process and a second transfer process. In this application, in the first transfer step of transferring from the sapphire substrate to the transfer substrate, the alignment step between the sapphire substrate and the transfer substrate will be explained in detail. Furthermore, a method for forming alignment marks used in the alignment process on the sapphire substrate will be explained in detail.

<LED holding substrate preparation process, first transfer substrate preparation process, second transfer substrate preparation process, and array substrate preparation process>
In the LED holding substrate preparation step shown in FIG. 5, the substrate SS1, the substrate SS2, and the substrate SS3 shown in FIG. 6 are prepared. FIG. 6 is a plan view schematically showing a substrate prepared in the LED holding substrate preparation step shown in FIG. 5. FIG. Each of the substrate SS1, the substrate SS2, and the substrate SS3 has an upper surface and a lower surface. Each of the LED holding substrates SS1, SS2, and SS3 has a plurality of LED elements arranged in a matrix on one of the top and bottom surfaces (in the example shown in FIG. 6, on the top surface). has been done.

Specifically, LED elements that emit light of different colors are arranged on the substrate SS1, the substrate SS2, and the substrate SS3, respectively. In other words, each of the substrate SS1, the substrate SS2, and the substrate SS3 is an LED holding substrate that holds a plurality of LED elements. For example, the first inorganic light emitting element 21, which is one of a red LED element, a green LED element, and a blue LED element, is arranged on the surface (element holding surface) SS1t of the substrate SS1. On the surface (element holding surface) SS2t of the substrate SS2, a second inorganic light emitting element 22 which is an LED element different from the first inorganic light emitting element 21 among a red LED element, a green LED element, and a blue LED element is disposed. are arranged. On the surface (element holding surface) SS3t of the substrate SS3, an LED element different from the first inorganic light emitting element 21 and the second inorganic light emitting element 22 among the red LED element, green LED element, and blue LED element is mounted. A certain third inorganic light emitting element 23 is arranged.

A plurality of first inorganic light emitting elements 21 are arranged in a matrix on the surface SS1t of the substrate SS1. The second inorganic light emitting element 22 and the third inorganic light emitting element 23 are not arranged on the surface SS1t of the substrate SS1. A plurality of second inorganic light emitting elements 22 are arranged in a matrix on the surface SS2t of the substrate SS2. The first inorganic light emitting element 21 and the third inorganic light emitting element 23 are not arranged on the surface SS2t of the substrate SS2. A plurality of third inorganic light emitting elements 23 are arranged in a matrix on the surface SS3t of the substrate SS3. The first inorganic light emitting element 21 and the second inorganic light emitting element 22 are not arranged on the surface SS3t of the substrate SS3. Each of the substrate SS1, the substrate SS2, and the substrate SS3 is, for example, a sapphire substrate. Each of the first inorganic light emitting element 21, the second inorganic light emitting element 22, and the third inorganic light emitting element 23 is formed by laminating, for example, a metal film, an insulating film, a semiconductor film, etc. on a sapphire substrate. . In other words, each of the substrate SS1, the substrate SS2, and the substrate SS3 is a substrate for manufacturing an LED.

Note that although the planar shapes of the substrate SS1, the substrate SS2, and the substrate SS3 are illustrated as circular in FIG. 6, the planar shapes of the substrate SS1, the substrate SS2, and the substrate SS3 are not limited to the circular shape, and may be square, for example, etc. There are various variations. For example, although FIG. 6 shows a wafer-shaped sapphire substrate, a portion of the wafer-shaped sapphire substrate may be cut out and used as a square substrate.

Further, a plurality of alignment marks AM are formed on the surface SS1t of the substrate SS1, the surface SS2t of the substrate SS2, and the surface SS3t of the substrate SS3, respectively. Below, alignment mark AM1 and alignment mark AM2 provided on surface SS1t of substrate SS1 will be explained. The substrate SS2 and the substrate SS3 are also provided with an alignment mark AM1 and an alignment mark AM2 similarly to the substrate SS1. In the alignment step of the first transfer step shown in FIG. 5, the sapphire substrate (substrate SS1) and the transfer substrate are aligned based on the position information of the plurality of alignment marks AM.

FIG. 7 is an enlarged plan view of the vicinity of the alignment mark shown in FIG. 6. As shown in FIG. 6, the plurality of alignment marks AM are located within a region where a plurality of LED elements (inorganic light emitting elements) 20 are arranged. In the case of this embodiment, alignment mark AM1 and alignment mark AM2 are blank areas formed by removing some of the plurality of LED elements 20. A method of forming a metal pattern of a different material or shape than that of the LED element 20 as the alignment mark AM may also be considered. In that case, in the process of forming the plurality of LED elements 20, it is necessary to perform a process of forming the alignment mark AM. In other words, the process of forming the alignment mark AM is added to the manufacturing process of forming the LED element 20. Furthermore, when adding a process for forming the alignment mark AM to the process for forming the LED element 20, the alignment mark AM is formed at the same position every time when producing a large number of substrates SS1. As a result, the versatility of the sapphire substrate on which the LED element 20 is formed is reduced.

On the other hand, in the case of the present embodiment, a blank area obtained by removing a portion of the plurality of LED elements 20 functions as the alignment mark AM. In this case, there is no need to add a process for forming the alignment mark AM to the process for forming the LED element 20, so it is possible to prevent a decrease in the versatility of the sapphire substrate. Note that, as a method for selectively removing a part of the plurality of LED elements 20, for example, a method of using a light shielding film when performing laser lift-off processing as described later can be exemplified. In the case of this method, the alignment mark AM can be provided at any position on the surface SSlt of the substrate SS1 shown in FIG. For example, in FIG. 6, an alignment mark AM1 is provided at the center of the surface SS1t of the substrate SS1, and an alignment mark AM2 is provided at the periphery of the surface SSt1. However, in the case of this embodiment, as a modification, for example, a plurality of alignment marks AM may be provided at the peripheral portion, or a plurality of alignment marks AM may be provided at the center portion. The position of the alignment mark AM can be easily changed according to product specifications and manufacturing equipment specifications.

As described above, the alignment mark AM is a blank area provided by removing a portion of the plurality of LED elements 20. Therefore, as shown in FIG. 7, the separation distance D1 between the LED elements 20 that are adjacent to each other via each of the plurality of alignment marks AM is wider than the separation distance D2 between the LED elements 20 that are adjacent to each other without the alignment mark AM interposed therebetween. . The region where the alignment mark AM is provided differs in the direction of light reflection and the reflectance of light from the region where the LED element 20 is formed. Therefore, even the alignment mark AM, which is a blank area, can be used as a mark for position identification in the alignment process described later.

FIG. 8 is an explanatory diagram showing an example of a method for providing the alignment mark shown in FIG. 6. FIG. 9 is an enlarged cross-sectional view of each of the plurality of substrates shown in FIG. 6. Note that since the cross-sectional structures of the substrate SS1, the substrate SS2, and the substrate SS3 are the same, one figure is shown as a representative, and the structure common to the substrate SS1, the substrate SS2, and the substrate SS3 is explained. Below, as a representative example, a substrate SS1 including a plurality of first inorganic light emitting elements 21 will be described. However, in the following description, the first inorganic light emitting element 21 is replaced with the second inorganic light emitting element 22 or the third inorganic light emitting element 23, the substrate SS1 is replaced with the substrate SS2 or the substrate SS3, and the surface SS1t is replaced with the surface SS2t or the surface SS3t. can be replaced with

As shown in FIG. 8, the LED holding substrate preparation process (see FIG. 5) includes an LED element forming process and an LED element removing process. In the LED element forming step, the LED element 20 is formed on the surface SS1t of the substrate SS1. In this step, for example, an LED element 20 shown in FIG. 9 is formed.

Each of the plurality of first inorganic light emitting elements 21 formed on the surface SS1t of the substrate SS1 shown in FIG. A P-type semiconductor layer 26 stacked on 25. The N-type semiconductor layer 24 is formed as a common base layer for the anode electrode 20EA and the cathode electrode 20EK, and the active layer 25 and the P-type semiconductor layer 26 are stacked on the anode electrode 20EA side. On the anode electrode 20EA side, a transparent electrode layer 27a is formed on the P-type semiconductor layer 26. The transparent electrode layer 27a on the anode electrode 20EA side and the N-type semiconductor layer 24 on the cathode electrode 20EK side are covered with a passivation film 28, which is an inorganic insulating film. Openings are formed in the passivation film 28 at locations where the anode electrode 20EA and the cathode electrode 20EK are to be formed. A metal electrode layer 27c is laminated in each opening with a seed layer 27b interposed therebetween. The anode electrode 20EA is a laminate of a transparent electrode layer 27a, a seed layer 27b, and a metal electrode layer 27c. On the other hand, the cathode electrode 20EK is a stack of a seed layer 27b and a metal electrode layer 27c stacked on the N-type semiconductor layer 24. A buffer layer 29 made of gallium nitride is formed between the N-type semiconductor layer 24 and the substrate SS1.

In the example shown in FIG. 9, the conductive bonding material 40 shown in FIG. 3 is not bonded to the electrode 20E of the first inorganic light emitting element 21, for example. However, as a modification, the conductive bonding material 40 shown in FIG. 3 may be bonded to the electrode 20E in advance.

Each of the substrate SS1, the substrate SS2, and the substrate SS3 is prepared, for example, before the first transfer step shown in FIG. 5. However, as a modified example, the case where the substrate SS1, the substrate SS2, and the substrate SS3 are not all prepared in advance before the first transfer step (specifically, the alignment step of the first transfer step of the first transfer step). There is also. For example, the substrate SS2 may be prepared at least before the second alignment step of the first transfer step shown in FIG. Further, it is sufficient that the substrate SS3 is prepared at least before the third alignment step of the first transfer step.

In the LED element removal step shown in FIG. 8, after selectively irradiating some of the plurality of LED elements from the substrate SS1 side with a laser, for example, ultraviolet laser light UVL, some of the LED elements 20 irradiated with the laser are selectively removed. remove it. In the example shown in FIG. 8, the ultraviolet laser light UVL is irradiated from the surface SS3b side of the substrate SS1. Further, a light shielding film LSF having an opening LSH is formed in advance on the surface SS1b of the substrate SS1.

When ultraviolet laser light UVL is irradiated from the surface SS1b side of the substrate SS1 through the light-shielding film LSF, the ultraviolet rays are blocked in the light-shielding film LSF, so the ultraviolet rays are selectively transmitted only to the portion irradiated to the opening LSH. do. The ultraviolet light that has passed through the opening LSH also passes through the substrate SS1 and is irradiated onto the LED element 20 formed on the surface SS1t.

As shown in FIG. 9, a buffer layer 29 made of gallium nitride is formed between the N-type semiconductor layer 24 of the LED element 20 and the surface SS1t of the substrate SS1. When the buffer layer 29 is irradiated with the laser light, the surface layer (a portion on the surface SS1t side) of the buffer layer 29 is modified, and it becomes possible to separate the substrate SS1 and the LED element 20. After the modification of the buffer layer 29 is completed, an adhesive sheet AS shown in FIG. 8 is attached to the LED element 20. Thereafter, when the adhesive sheet AS is pulled away from the substrate SS1 in a direction away from the substrate SS1, the LED element 20 irradiated with the ultraviolet laser beam UVL is peeled off from the substrate SS1 and removed by the adhesive sheet AS. Moreover, this LED element removal process can also be rephrased as an alignment mark forming process.

Further, although not shown, the light shielding film LSF formed on the surface SS1b of the substrate SS1 is removed after the LED element removal step. Through each of the above steps, a part of the plurality of LED elements 20 is selectively removed, and an alignment mark AM shown in FIG. 7 is formed.

In the example shown in FIG. 6, the plurality of alignment marks AM includes an alignment mark AM1 and an alignment mark AM2 having a planar shape different from that of the alignment mark AM1. When a plurality of alignment marks AM having mutually different planar shapes are provided in this way, the direction of the electrodes of the LED element 20 can be confirmed. For example, assume that the first direction is the direction from alignment mark AM1 to alignment mark AM2, and a rule is set in which the anode electrode is placed on the upper side in the first direction and the cathode electrode is placed on the lower side in the first direction. . In this case, the position of the electrode can be determined by analyzing the positional relationship between alignment mark AM1 and alignment mark AM2. As a result, it is possible to transfer the anode electrode and the cathode electrode without making a mistake in their positional relationship.

In the first transfer substrate preparation step and the second transfer substrate preparation step shown in FIG. 5, transfer substrates TR1 and TR2 shown in FIGS. 10 and 11 are prepared. FIG. 10 is a plan view showing an example of a transfer substrate used in the first transfer step and the second transfer step shown in FIG. 5. FIG. FIG. 11 is a cross-sectional view taken along line AA in FIG. 10. Since the transfer substrate TR1 and the transfer substrate TR2 can have the same structure, FIGS. 10 and 11 representatively show one diagram to explain the structure common to the transfer substrate TR1 and the transfer substrate TR2. ing. The transfer substrate TR1 used in the first transfer step shown in FIG. 5 will be described below as a representative example. However, in the following description, the portion described as transfer substrate TR1 can be replaced with transfer substrate TR2.

As shown in FIG. 10, the transfer substrate TR1 has a rectangular shape in plan view. The transfer substrate TR1 has a side TRs1 extending in the X direction, a side TRs2 on the opposite side of the side TRs1 in the Y direction intersecting the X direction, a side TRs3 extending in the Y direction, and a side TRs3 on the opposite side of the side TRs3 in the X direction. It has a certain side TRs4. The transfer substrate TR1 also includes an element placement area R1, which is a planned area for pasting any one of the first inorganic light emitting element 21, the second inorganic light emitting element 22, and the third inorganic light emitting element 23 shown in FIG. It has a peripheral region R2 around the arrangement region R1. Further, the transfer substrate TR1 has a plurality of (two in FIG. 10) metal patterns MP.

As shown in FIG. 11, the transfer substrate TR1 includes a surface TRt on which the adhesive resin layer 50 is formed, and a surface TRb located on the opposite side of the surface TRt. Each of the plurality of metal patterns MP is formed on the surface TRt and covered with the adhesive resin layer 50. The plurality of metal patterns MP are patterns made of a metal material, and are used as alignment marks in the alignment step of the first transfer step shown in FIG. The type of metal material constituting the metal pattern MP is not particularly limited, but examples include copper and aluminum. Further, it is preferable that the metal pattern MP is placed at a position where it does not get in the way during the process of transferring the plurality of LED elements 20. In the example shown in FIG. 10, each of the plurality of metal patterns MP is formed in a peripheral region R2 around an element arrangement region R1.

The adhesive resin layer 50 has a surface 50b facing the surface TRt of the transfer substrate TR1 and a surface 50t opposite to the surface 50b. The surface 50t has adhesiveness, and in the pasting process of the first transfer process shown in FIG. It is possible to hold three inorganic light emitting elements 23). Further, in the alignment step of the first transfer step, the second alignment step, and the third alignment step shown in FIG. 5, it is necessary to visually recognize the metal pattern MP through the adhesive resin layer 50. Therefore, the adhesive resin layer 50 has transparency (visible light transmittance).

Furthermore, in the array substrate preparation step, an array substrate SUB1 shown in FIG. 12 is prepared. FIG. 12 is a cross-sectional view schematically showing an array substrate prepared in the array substrate preparation step shown in FIG. A large number of terminals 30 are arranged in a matrix in the display area DA of the array substrate SUB1, and FIG. 12 representatively shows some of them.

As shown in FIG. 12, the transfer substrate TR1 includes a surface SUBt and a surface SUBb on the opposite side of the surface SUBt. The surface SUBt is a mounting surface on which a plurality of LED elements 20 shown in FIG. 6 are planned to be mounted. The array substrate SUB1 has a plurality of terminals 30. The plurality of terminals 30 include a terminal (first terminal) 31 that is scheduled to be electrically connected to the first inorganic light emitting element 21 (see FIG. 6). The plurality of terminals 30 include a terminal (second terminal) 32 that is to be electrically connected to the second inorganic light emitting element 22 (see FIG. 6). Further, the plurality of terminals 30 include a terminal (third terminal) 33 that is scheduled to be electrically connected to the third inorganic light emitting element 23 (see FIG. 6). Each of the terminals 31, 32, and 33 is arranged in a matrix corresponding to the position of the pixel PIX shown in FIG.

In the example shown in FIG. 12, a conductive bonding material 40 as a protruding electrode is formed on each of the plurality of terminals 30 in advance. However, as a modification, the conductive bonding material 40 may not be bonded to the terminal 30 in advance.

<First transfer step>
Next, the first transfer step shown in FIG. 5 will be explained. In the example shown in FIG. 5, the first transfer process includes an alignment process, a pasting process, and a holding substrate peeling process. In the first transfer process, a cycle of an alignment process, a pasting process, and a holding substrate peeling process is performed multiple times depending on the number of colors of the LED elements 20. In the example of this embodiment, the first transfer step includes a step of transferring each of the plurality of first inorganic light emitting elements 21 on the substrate SS1 shown in FIG. 6 onto the transfer substrate TR1 shown in FIG. Transferring each of the plurality of second inorganic light emitting elements 22 above onto another new transfer substrate TR1, and transferring each of the plurality of third inorganic light emitting elements 23 on the substrate SS3 to yet another new transfer substrate. and a step of transferring it to TR1. Below, a process of transferring a plurality of LED elements 20 formed on the substrate SS1 to the transfer substrate TR1 will be described as a representative example among the plurality of cycles included in the first transfer process.

<Positioning process>
FIG. 13 is a cross-sectional view schematically showing the alignment step of the first transfer step shown in FIG. 5. FIG. In the alignment step of the first transfer step shown in FIG. 5, as shown in FIG. 13, the surface SS1t of the substrate SS1 and the surface TRt of the transfer substrate TR1 are aligned. In the example shown in FIG. 13, the alignment mark AM (and metal pattern MP) is photographed by the image sensor 71 with the substrate SS1 held on the stage 61 and the transfer substrate TR1 held on the stage 62 facing each other. Then, based on the positional information of the alignment mark AM (and metal pattern MP), the substrate SS1 and the transfer substrate TR1 are aligned. Specifically, the position of each of the plurality of LED elements 20 formed on the surface SS1t of the substrate SS1 and the position of the element arrangement region R1 on the adhesive resin layer 50 formed on the surface TRt of the transfer substrate TR1. Adjust relationships.

The stage 61 is a member capable of holding the substrate SS1. The surface SS1b of the substrate SS1 is held by the holding surface 61h of the stage 61. The stage 62 is a member capable of holding the transfer substrate TR1. The surface TRb of the transfer substrate TR1 is held by the holding surface 62h of the stage 62. The method for the stage 61 to hold the substrate SS1 and the method for the stage 62 to hold the transfer substrate TR1 include, for example, a suction holding method, or a fixing jig (not shown) for fixing the peripheral edge of the substrate SS1 or the transfer substrate TR1. For example, a method of fixing with a chuck), etc. Further, each of the stage 61 and the stage 62 is connected to a control device 72, and can be moved independently of each other in a plane direction (XY plane direction) based on a command signal output from the control device. Equipped with a mechanism.

The image sensor 71 is arranged between the substrate SS1 and the transfer substrate TR1, and the control device 72 and the image sensor 71 are electrically connected. The image sensor 71 images the alignment mark AM on the substrate SS1 side and outputs image data to the control device 72. Further, the image sensor 71 images a plurality of metal patterns MP as alignment marks on the transfer substrate TR1 side, and outputs image data to the control device 72. Note that the scope of the image sensor 71 can be used to image two or more alignment marks AM (or metal patterns MP) at once, or to sequentially image two or more alignment marks AM (or metal patterns MP). There is.

The control device 72 that has acquired the image data from the image sensor 71 determines the position of the metal pattern MP based on the position information of the stage 62 when the image sensor 71 imaged the metal pattern MP and the analysis result of the image data of the metal pattern MP. calculate. Similarly, the control device 72 calculates the position of the LED element 20 from the position information of the stage 61 when the image sensor 71 images the alignment mark AM and the analysis result of the image data of the alignment mark AM. Then, based on the position information of the metal pattern MP and the position information of the LED element 20, at least one of the stage 61 and the stage 62 is operated along the XY plane, and a plurality of LEDs are placed on a preset transfer position. Adjust so that each of the elements 20 is positioned.

<Pasting process>
FIG. 14 is a cross-sectional view schematically showing the pasting step of the first transfer step shown in FIG. In the attaching step of the first transfer step, as shown in FIG. 14, each of the plurality of LED elements 20 is attached to the adhesive resin layer 50 on the transfer substrate TR1.

In the above alignment process, when the distance between the stage 61 and the stage 62 is brought closer after alignment in the direction along the XY plane, the plurality of Each of the LED elements 20 approaches the transfer substrate TR1. When the distance between the substrate SS1 and the transfer substrate TR1 is further reduced, a portion of each of the plurality of LED elements 20 is adhered to the adhesive resin layer 50. At this time, a portion of the electrode 20E shown in FIG. 9 (or a portion of the conductive bonding material 40 shown in FIG. 3) of the LED element 20 is adhered to the adhesive resin layer 50.

<Holding substrate peeling process>
Next, the holding substrate peeling step of the first transfer step shown in FIG. 5 will be explained. FIG. 15 is a cross-sectional view schematically showing a state in which a plurality of LED elements are irradiated with laser in the holding substrate peeling step of the first transfer step shown in FIG. FIG. 16 is a cross-sectional view schematically showing a state in which the holding substrate is peeled off from a plurality of LED elements in the holding substrate peeling step of the first transfer step shown in FIG. In the holding substrate peeling process of the first transfer process, as shown in FIG. 16, the substrate SS1 and the plurality of LED elements 20 are peeled off. In FIGS. 15 and 16, for ease of viewing, illustrations of the substrate SS2, the substrate SS3, the surface SS2t, the surface SS2b, the surface SS3t, and the surface SS3b are omitted. The illustrated substrate SS1 can be replaced with a substrate SS2 or a substrate SS3.

For example, a technique called laser lift-off can be used as a method for peeling off the close contact interface between the surface SS1t of the substrate SS1, which is the holding substrate, and the plurality of LED elements 20. When using a technique called laser lift-off, as schematically shown in FIG. 15, for example, ultraviolet laser light UVL is emitted from the surface SS1b side of the substrate SS1 toward the contact interface between the surface SS1t of the substrate SS1 and the plurality of LED elements 20. irradiate. As already explained using FIG. 9, when the buffer layer 29 is irradiated with the ultraviolet laser beam UVL, the surface layer (a part on the surface SS1t side) of the buffer layer 29 is modified, and the substrate SS1 and the LED element 20 are It becomes possible to peel it off.

In the case of this embodiment, a light shielding film LS2 is disposed between the light source UVS of the ultraviolet laser beam UVL and the substrate SS1 (in the example shown in FIG. 15, between the stage 61 and the light source UVS). The light shielding film LS2 has a plurality of openings and can be moved along the XY plane. In the example shown in FIG. 15, the light shielding film LS2 is attached to the light source UVS. By providing the light shielding film LS2 between the light source UVS and the substrate SS1, a portion of the plurality of LED elements 20 can be selectively irradiated with the ultraviolet laser light UVL. In the case of the present embodiment, in the first transfer step, some of the plurality of LED elements 20 on the substrate SS1 are selectively transferred to the transfer substrate TR1, thereby forming the array substrate SUB1 (see FIG. 12). The LED elements 20 can be transferred to positions corresponding to the terminal arrangement.

After the modification of the buffer layer 29 is completed, as shown in FIG. 16, the distance between the substrate SS1 and the transfer substrate TR1 is separated. At this time, each of the plurality of LED elements 20 is attached to the adhesive resin layer 50. Therefore, among the plurality of LED elements 20, the LED element 20 whose buffer layer 29 has been modified is peeled off from the substrate SS1, and a structure in which the plurality of LED elements 20 are pasted on the transfer substrate TR1 is obtained. . On the other hand, the LEDs that are not irradiated with the ultraviolet laser beam UVL are not peeled off from the substrate SS1 and are transferred to another transfer substrate.

Although the example shown in FIG. 15 shows an example in which some of the plurality of LED elements 20 are selectively irradiated with ultraviolet laser light UVL, as a modified example, all the LED elements 20 are irradiated at once. Ultraviolet laser light UVL may be irradiated. For example, in the process of forming the LED elements 20 on the substrate SS1, if the LED elements are formed in advance at a pitch that matches the terminal arrangement of the array substrate SUB1, all the LED elements 20 may be transferred in this process. Can be done. However, considering the versatility of the sapphire substrate, it is preferable to adjust the arrangement of the LED elements 20 in this step.

Through the above steps, a structure in which a plurality of first inorganic light emitting elements 21 are pasted on the transfer substrate TR1 is obtained. A structure in which a plurality of second inorganic light emitting elements 22 (see FIG. 6) are pasted on the transfer substrate TR1 by similarly performing the above-described alignment step, pasting step, and holding substrate peeling step; A structure is obtained in which a plurality of third inorganic light emitting elements 23 (see FIG. 6) are pasted on the transfer substrate TR1.

<Second transfer process>
Next, the second transfer process shown in FIG. 5 will be explained. FIG. 17 is an explanatory diagram showing an example of the second transfer step shown in FIG. 5. In addition, in the second transfer step, the three types of LED elements 20 are sequentially pasted on one transfer substrate TR2, and in the peeling step, the transfer substrate TR1 is attached using the difference in adhesive strength of the adhesive resin layer. The process is the same as the first transfer process described above except for peeling. Therefore, among the alignment process, pasting process, and holding substrate peeling process included in the second transfer process, explanations that overlap with those already given will be omitted, and the explanation will focus on the differences.

As shown in FIG. 17, in the second transfer step, a plurality of first inorganic light emitting elements 21, a plurality of second inorganic light emitting elements 22, and a plurality of third inorganic light emitting elements 23 are transferred to one transfer substrate TR2. transcribed in order. The transfer substrate TR2 has the same structure as the transfer substrate TR1, except that the adhesive force of the adhesive resin layer 51 is higher than the adhesive force of the adhesive resin layer 50 of the transfer substrate TR1. For example, metal pattern MP and metal pattern MP2 shown in FIG. 17 are made of the same metal material and have the same shape.

Similar to the alignment process of the first transfer process, the alignment process of the second transfer process uses the stage 61, stage 62, image sensor 71, and control device 72 described using FIG. It can be carried out. In this step, a metal pattern MP is used as an alignment mark for specifying the position of the transfer substrate TR1. Further, a metal pattern MP2 is used as an alignment mark for specifying the position of the transfer substrate TR2. In addition, in the step of transferring the second inorganic light emitting element 22, alignment is performed so that the second inorganic light emitting element 22 is arranged between adjacent first inorganic light emitting elements 21. Further, in the step of transferring the third inorganic light emitting element 23, alignment is performed so that the third inorganic light emitting element 23 is disposed between the adjacent first inorganic light emitting element 21 and second inorganic light emitting element 22.

The pasting process in the second transfer process is similar to the pasting process in the first transfer process, except that the plurality of LED elements 20 are pasted on the adhesive resin layer 51 formed on the transfer substrate TR2. Furthermore, in the holding substrate peeling step of the second transfer step, the transfer substrate TR1 is peeled off from the LED element 20 by utilizing the difference in adhesive strength between the adhesive resin layer 50 and the adhesive resin layer 51, as described above. Therefore, in this step, irradiation with ultraviolet laser light UVL as shown in FIG. 15 is not performed. The adhesive strength (in other words, adhesive strength) of the adhesive resin layer 51 is higher than the adhesive strength of the adhesive resin layer 50. Therefore, when the distance between the transfer substrate TR1 and the transfer substrate TR2 is increased, the LED element 20 is peeled off from the adhesive resin layer 50, which has relatively low adhesive strength. Through this step, a structure is obtained in which a plurality of first inorganic light emitting elements 21, a plurality of second inorganic light emitting elements 22, and a plurality of third inorganic light emitting elements 23 are pasted on the transfer substrate TR2. The plurality of first inorganic light emitting elements 21, the plurality of second inorganic light emitting elements 22, and the plurality of third inorganic light emitting elements 23 mounted on the transfer substrate TR2 are mounted on the transfer substrate TR1 before the start of the second transfer process. The plurality of first inorganic light emitting elements 21, the plurality of second inorganic light emitting elements 22, and the plurality of third inorganic light emitting elements 23 pasted on are upside down. In the case of this embodiment, the electrode 20E of the LED element 20 shown in FIG. 9 is arranged on the opposite side of the surface facing the adhesive resin layer 51 shown in FIG. 17.

<Array board mounting process>
Next, the array substrate mounting process shown in FIG. 5 will be described. FIG. 18 is a cross-sectional view showing an example of the array substrate mounting process shown in FIG. 5. In the array substrate mounting process, first, the array substrate SUB1 and the transfer substrate TR2 shown in FIG. 18 are aligned.

In the array substrate mounting step, each of the plurality of first inorganic light emitting elements 21, the plurality of second inorganic light emitting elements 22, and the plurality of third inorganic light emitting elements 23 are collectively mounted on the array substrate SUB1 shown in FIG. 12. At this time, it is necessary to ensure that the plurality of electrodes 20E shown in FIG. 9 and the plurality of terminals 30 shown in FIG. 12 face each other, so it is necessary to perform highly accurate positioning. Therefore, in this embodiment, a metal pattern MP3 is formed on the surface SUBt of the array substrate SUB1. The metal pattern MP3 is a pattern used as an alignment mark in the array substrate mounting process. The metal pattern MP3 is made of the same metal material and has the same shape as the metal pattern MP2 of the transfer substrate TR2, for example. Further, the metal pattern MP3 is arranged at a position facing the metal pattern MP2, for example, in the alignment process described below.

In the case of this embodiment, the array substrate mounting process includes an alignment process of aligning the transfer substrate TR2, the array substrate SUB1, and the array substrate SUB1. The alignment process can be performed in the same way as the alignment process of the first transfer process described using FIG. 13. This process is the same except that the metal pattern MP3 is used as an alignment mark for specifying the position of the array substrate SUB1.

In the array substrate mounting process, after the alignment process, the distance between the transfer substrate TR2 and the array substrate SUB1 is brought closer, and the LED elements 20 and the terminals 30 are electrically connected via the conductive bonding material 40. Includes a joining process. In the bonding step, the electrode 20E of the LED element 20 (see FIG. 9) and the terminal 30 of the array substrate SUB1 are electrically connected via the conductive bonding material 40. In this step, the conductive bonding material 40 is melted by applying heat, and the electrode 20E and the terminal 30 are bonded via the conductive bonding material 40. As a heat source for heating the conductive bonding material 40, for example, a method of irradiating laser light can be exemplified. As described above, when a heating process is included, there is a concern that the resin alignment mark may be deformed. On the other hand, in the case of this embodiment, since each of the metal pattern MP2 of the transfer substrate TR2 and the metal pattern MP3 of the array substrate SUB1 is made of metal, deformation can be prevented even if a heating process is included.

In the array substrate mounting process, after the bonding process, each of the plurality of first inorganic light emitting elements 21, the plurality of second inorganic light emitting elements 22, and the plurality of third inorganic light emitting elements 23 are attached to the adhesive resin of the transfer substrate TR2. It includes a peeling step of peeling off the layer 51. At the start of this process, each of the plurality of first inorganic light emitting elements 21, the plurality of second inorganic light emitting elements 22, and the plurality of third inorganic light emitting elements 23 have already been joined to the terminals 30 of the array substrate SUB1. Therefore, when the distance between the transfer substrate TR2 and the array substrate SUB1 is increased, the LED element 20 is peeled off from the adhesive resin layer 51. Through this step, a structure in which a plurality of first inorganic light emitting elements 21, a plurality of second inorganic light emitting elements 22, and a plurality of third inorganic light emitting elements 23 are mounted on the array substrate SUB1 is obtained.

Note that in the example shown in FIG. 5, an embodiment has been described in which three types of LED elements are sequentially mounted, but the types of LED elements to be mounted are not limited to three types. For example, if it is sufficient to mount one type of LED elements all at once, it is possible to omit the first transfer step and second transfer step shown in FIG. 5 and mount them directly from the LED holding substrate to the array substrate. can. For example, in the case of a method for manufacturing a display device in which two types of LED elements are mounted, the first transfer step cycle shown in FIG. 5 may be performed twice, and the second transfer step cycle may be repeated twice. Furthermore, in the case of a method of manufacturing a display device that mounts four or more types of LED elements, it is necessary to increase the number of times the first transfer step and the second transfer step shown in FIG. 5 are performed.

Although the embodiment and typical modified examples have been described above, the above-described technology is applicable to various modified examples other than the illustrated modified examples. For example, the above-described modifications may be combined.

It is understood that those skilled in the art will be able to come up with various changes and modifications within the scope of the idea of the present invention, and these changes and modifications will also fall within the scope of the present invention. For example, the gist of the present invention may be obtained by adding, deleting, or changing the design of components, or adding, omitting, or changing conditions to the above-mentioned embodiments as appropriate by a person skilled in the art. It is within the scope of the present invention as long as it has the following.

INDUSTRIAL APPLICATION This invention can be utilized for a display device and an electronic device in which a display device is incorporated.

5 Control circuit 6 Drive circuit 10 Substrate 10b, 10f Surface 11 Inorganic insulating layer 12, 13 Organic insulating layer 20, 20M1 LED element 20b, 20f Surface 20E Electrode 20EA Anode electrode 20EK Cathode electrode 21 First inorganic light emitting element 22 Second inorganic light emitting element Element 23 Third inorganic light emitting element 24 N-type semiconductor layer 25 Active layer 26 P-type semiconductor layer 27a Transparent electrode layer 27b Seed layer 27c Metal electrode layer 28 Passivation film 29 Buffer layer 30, 30H, 30L, 31, 32, 33 Terminal 40 Conductive bonding material 50, 51 Adhesive resin layer 50b, 50t Surface 61, 62 Stage 61h, 62h Holding surface 71 Image sensor 72 Control device AM, AM1, AM2 Alignment mark AS Adhesive sheet BCT Output switch Cad Auxiliary capacitor Cs Holding capacitor DA Display Area DRT Drive transistor DSP1 Display device GL, GLA, GLB Scanning signal line GLR Reset wiring Gsb, Gsr, Gss Control signal MP, MP2, MP3 Metal pattern PFA Peripheral area PIX Pixel PVD, PVS Potential R1 Element placement area R2 Peripheral area RST Reset Switches SS1, SS2, SS3 Substrate SS1b Surface SS1t, SS2t, SS3t Surface (element holding surface)
SST Pixel switch SUB1 Array substrate SUBb, SUBt Surfaces TR1, TR2 Transfer substrates TRb, TRt Surfaces TRs1, TRs2, TRs3, TRs4 Side UVL Ultraviolet laser light VL Video signal line Vsg Video signal

Claims (4)

(a) a first substrate having a first surface on which a plurality of inorganic light emitting elements are arranged in a matrix; and a second substrate having a second surface on which an adhesive resin layer is formed. the process of preparing,
(b) aligning the first substrate and the second substrate;
(c) after the step (b), attaching each of the plurality of inorganic light emitting elements to the adhesive resin layer on the second substrate;
(d) After the step (c), separating each of the plurality of inorganic light emitting elements from the first substrate by increasing the distance between the first substrate and the second substrate;
including;
In the step (b), the first substrate and the second substrate are aligned based on position information of a plurality of alignment marks provided on the first surface of the first substrate,
The plurality of alignment marks are within a region where the plurality of inorganic light emitting elements are arranged, and the distance between adjacent inorganic light emitting elements with one alignment mark in between is such that A method for manufacturing a display device in which the distance between adjacent inorganic light emitting elements is wider than the distance between adjacent inorganic light emitting elements. In claim 1,
The step (a) is
(a1) forming the plurality of inorganic light emitting elements on the first surface;
(a2) selectively irradiating a portion of the plurality of inorganic light emitting devices from the first substrate side with an ultraviolet laser, and then selectively removing the portion of the inorganic light emitting devices irradiated with the ultraviolet laser; ,
A method for manufacturing a display device, including: In claim 2,
The method for manufacturing a display device, wherein the plurality of alignment marks include a first alignment mark and a second alignment mark having a planar shape different from that of the first alignment mark. In claim 2 or claim 3,
In the step (d), a part of the plurality of inorganic light emitting elements formed on the first substrate is selectively irradiated with an ultraviolet laser to selectively irradiate the inorganic light emitting elements irradiated with the ultraviolet laser. A method for manufacturing a display device, the method comprising transferring onto the second substrate.

Images