JP2022190832A - Pressing jig and transfer device - Google Patents

Abstract

A pressing jig or a transfer device capable of suppressing temperature rise due to laser light irradiation is provided.
A pressing jig presses an element substrate provided with an LED element against a circuit substrate provided with a pixel circuit for driving the LED element. It includes a plate-like member that transmits the irradiated laser light and a cooling part that cools the plate-like member. The transfer device includes a stage on which a circuit board provided with pixel circuits for driving LED elements is placed, a laser irradiation unit that irradiates the LED elements with laser light, a plate-like member that transmits the laser light, and a plate-like member. and a pressing jig for pressing the element substrate provided with the LED elements against the circuit board.
[Selection drawing] Fig. 1

Description

One embodiment of the present invention relates to a transfer device for transferring LED (Light Emitting Diode) elements. Further, one embodiment of the present invention relates to a pressing jig used in the transfer device.

2. Description of the Related Art In recent years, as a next-generation display device, development of a micro LED display in which a minute LED element is mounted in each pixel has been advanced. A micro LED display has a structure in which a plurality of LED elements are mounted on a circuit board on which pixel circuits are formed.

There are various methods for mounting a micro LED element on a circuit board. For example, a so-called laser lift-off method is known, in which an element substrate provided with micro LED elements and a circuit board are brought into close contact with each other, and a laser beam is irradiated to transfer the micro LED elements from the element substrate to the circuit board. (See, for example, Patent Document 1).

U.S. Patent No. 10096740

In Patent Document 1, a light-shielding mask is used to irradiate a laser beam during laser lift-off, but the laser light is absorbed by the light-shielding mask, which raises the temperature of the light-shielding mask. Moreover, not only the light-shielding mask but also the element substrate and the circuit board absorb the laser light, and there is a problem that the micro LED element is damaged by the heat.

An object of one embodiment of the present invention is to provide a transfer apparatus capable of suppressing a temperature rise due to laser light irradiation in laser lift-off of an LED element. Another object of an embodiment of the present invention is to provide a pressing jig capable of suppressing temperature rise due to irradiation of laser light.

A pressing jig according to an embodiment of the present invention is a pressing jig for pressing an element substrate provided with LED elements against a circuit substrate provided with pixel circuits for driving the LED elements, and the pressing jig is , a plate-like member that transmits laser light irradiated to the LED element, and a cooling part that cools the plate-like member.

Further, a transfer apparatus according to an embodiment of the present invention includes a stage on which a circuit board provided with pixel circuits for driving LED elements is placed, a laser irradiation section for irradiating the LED elements with laser light, a laser light and a cooling part for cooling the plate-like member and the plate-like member for transmitting the light, and a pressing jig for pressing the element substrate on which the LED elements are provided against the circuit board.

1 is a schematic diagram of a transfer device according to one embodiment of the present invention; FIG. 3 is a schematic perspective view of a pressing jig of the transfer device according to one embodiment of the present invention; FIG. 4 is a schematic plan view of a pressing jig of the transfer device according to one embodiment of the present invention; FIG. It is a flowchart figure which shows the transfer method of the LED element using the transfer device which concerns on one Embodiment of this invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. It is a typical sectional view showing the transfer method of the LED element using the transfer device concerning one embodiment of the present invention. 1 is a plan view showing a schematic configuration of a display device manufactured using a transfer device according to an embodiment of the present invention; FIG. It is a block diagram which shows the circuit structure of the display apparatus manufactured using the transfer apparatus which concerns on one Embodiment of this invention. 1 is a circuit diagram showing the configuration of a pixel circuit of a display device manufactured using a transfer device according to one embodiment of the present invention; FIG. 1 is a cross-sectional view showing the configuration of a pixel of a display device manufactured using a transfer device according to one embodiment of the present invention; FIG. 1 is a schematic perspective view of a pressing jig according to one embodiment of the present invention; FIG. 1 is a schematic cross-sectional view of a pressing jig according to one embodiment of the present invention; FIG. 1 is a schematic perspective view of a pressing jig according to one embodiment of the present invention; FIG. 1 is a schematic cross-sectional view of a pressing jig according to one embodiment of the present invention; FIG. 1 is a schematic perspective view of a pressing jig according to one embodiment of the present invention; FIG. 1 is a schematic cross-sectional view of a pressing jig according to one embodiment of the present invention; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention can be implemented in various modes without departing from the gist thereof. The present invention should not be construed as being limited to the description of the embodiments exemplified below. In order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual mode. However, the drawings are merely examples and are not intended to limit the interpretation of the invention.

When describing the embodiments of the present invention, the direction from the circuit board toward the LED elements is defined as "up", and the opposite direction is defined as "down". However, the expressions "above" or "below" merely describe the upper limit relationship of each element. For example, the expression that LED elements are arranged on a circuit board also includes the case where another member is interposed between the circuit board and the LED elements. Furthermore, the expressions “above” or “below” include not only cases where each element overlaps in plan view, but also cases where each element does not overlap.

When describing the embodiments of the present invention, elements having functions similar to those of elements already described may be denoted by the same reference numerals or the same reference numerals with symbols such as alphabets, and description thereof may be omitted. In addition, when it is necessary to distinguish a certain element for each color of RGB, it is distinguished by adding a symbol of R, G or B after the code indicating the element. However, when it is not necessary to describe the elements separately for each color of RGB, only the symbols indicating the elements will be used for description.

<First embodiment>
[1. Configuration of transfer device 10]
A transfer device 10 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 2B. FIG. 1 is a schematic diagram of a transfer device 10 according to one embodiment of the present invention. 2A and 2B are a schematic perspective view and a plan view, respectively, of the pressing jig 200 of the transfer device 10 according to one embodiment of the present invention.

As shown in FIG. 1 , the transfer device 10 includes a stage 100 , a pressing jig 200 , a laser irradiation section 300 and a light shielding mask 400 . The pressing jig 200 is arranged above the stage 100 . Also, the laser irradiation unit 300 is arranged above the pressing jig 200 . However, the arrangement of the laser irradiation unit 300 is not limited to this. The laser irradiator 300 may have any structure as long as it can irradiate laser light from above the pressing jig 200 . A light shielding mask 400 is arranged between the stage 100 and the pressing jig 200 .

The stage 100 supports a circuit board 900 provided with pixel circuits for driving LED elements. Therefore, the stage 100 has a flat surface on which the circuit board 900 is placed. For example, the circuit board 900 is a glass substrate or a flexible resin substrate. A pixel circuit is formed by a plurality of TFTs (Thin Film Transistors) on a glass substrate or a resin substrate, and the circuit substrate 900 may also be called a TFT substrate 900 . Although the details will be described later, when transferring the LED elements, the element substrate 800 provided with the LED elements is placed on the circuit board 900 .

The pressing jig 200 presses the element substrate 800 so that the LED elements of the element substrate 800 are in close contact with the circuit board 900 on the stage 100 . More specifically, the pressing jig 200 can press and hold the element substrate 800 through the light shielding mask 400 after the light shielding mask 400 is placed on the element substrate 800 . The pressing jig 200 may press the element substrate 800 by applying an external force. Moreover, the pressing jig 200 may include a pressure sensor so that the pressing force can be detected.

As shown in FIGS. 2A and 2B, pressing jig 200 includes plate-like member 210 and heat sink 220 . The plate-like member 210 transmits laser light of a predetermined wavelength emitted from the laser irradiation section 300 . Quartz glass, for example, can be used as the plate member 210 . The heat sink 220 is provided in contact with the plate-like member 210 in the peripheral portion of the plate-like member 210 . In other words, the heat sink 220 is provided around the transmissive region 230 irradiated with laser light. The heat sink 220 can absorb or dissipate heat from the plate member 210 . That is, the heat sink 220 can function as a cooling section that cools the plate-like member 210 . As the heat sink 220, for example, a metal material with high thermal conductivity, such as a metal material such as aluminum, iron, or copper, or an alloy material containing these metal materials can be used.

The heat sink 220 has a plurality of protrusions (fins). The shape of the fins of the heat sink 220 shown in FIG. 2A is flat, but the shape of the fins is not limited to this. The fins may have a shape that increases the surface area of the heat sink 220 . For example, the shape of the fins may be conical or bellows.

A fan may be installed in the heat sink 220 . By rotating the fan to convect the air around the heat sink 220, the heat dissipation efficiency of the heat sink 220 is improved.

The laser irradiation unit 300 irradiates the LED elements with laser light through the transmission region 230 of the pressing jig 200 . The laser irradiation unit 300 can irradiate two types of laser light with different wavelengths. Although details will be described later, the laser irradiation unit 300 can irradiate a first laser beam having a wavelength in the infrared region or the near-infrared region and a second laser beam having a wavelength in the ultraviolet region. A solid-state laser such as a YAG laser or a _YVO4 laser can be used as the light source of the first laser beam. As a light source for the second laser beam, a solid-state laser such as YAG laser or _YVO4 laser, or an excimer laser can be used.

The laser irradiation unit 300 may scan a laser beam to irradiate a plurality of LED elements, or may divide the laser beam into a plurality of beams and irradiate the plurality of LED elements at the same time. Also, the laser irradiation unit 300 may form a linear or rectangular laser beam and irradiate a plurality of LED elements at the same time.

The light-shielding mask 400 includes regions (for example, openings) that transmit laser light and regions that block laser light. Therefore, the light shielding mask 400 can be adjusted so that only predetermined LED elements on the element substrate 800 are irradiated with laser light.

Although not shown, the transfer apparatus 10 may include a transport section that transports the element substrate 800 or the circuit board 900 onto the stage 100 . Further, the transfer device 10 may include an alignment section that adjusts the positions of the element substrate 800 and the circuit substrate 900 .

[2. Transfer method of LED element by transfer device 10]
A method for transferring LED elements using the transfer device 10 according to one embodiment of the present invention will be described with reference to FIGS. 3 to 4G. FIG. 3 is a flow chart showing a method for transferring LED elements using the transfer device 10 according to one embodiment of the present invention. 4A to 4G are schematic cross-sectional views showing a method for transferring LED elements using the transfer device 10 according to one embodiment of the present invention.

At step S100 in FIG. 3, the circuit board 900 is placed on the stage 100 (see FIG. 4A). The circuit board 900 includes a support substrate 910 having an insulating surface, a plurality of pixel circuits 920 each driving an LED element, and connection electrodes 930 connected to the pixel circuits 920 . As the supporting substrate 910, a glass substrate, a resin substrate, a ceramic substrate, a metal substrate, or the like can be used. Pixel circuits are formed from TFTs formed on a support substrate. The connection electrode 930 is formed corresponding to the structure of the mounted LED element. As the connection electrode 930, a conductive metal material such as tin (Sn) can be used. The thickness of the connection electrode 930 is 0.2 μm or more and 5 μm or less, preferably 1 μm or more and 3 μm or less. Details of the structure of the circuit board 900 and the pixel circuit 920 will be described later.

In step S200 of FIG. 3, the element substrate 800 is placed on the circuit board 900 so that the connection electrodes 930 of the circuit board 900 and the LED elements 820R of the element substrate 800 face each other (see FIG. 4B). The element substrate 800 is a semiconductor substrate 810 provided with a plurality of LED elements 820R that emit red light. A sapphire substrate or the like can be used as the semiconductor substrate 810 . LED element 820R includes a semiconductor material such as gallium nitride grown on a sapphire substrate. The semiconductor material may be appropriately determined depending on the emission color.

The terminal electrode 830R of the LED element 820R overlaps with the connection electrode 930 of the pixel corresponding to red among the plurality of connection electrodes 930 . At this time, the element substrate 800 may be temporarily fixed by providing an adhesive layer (not shown) between each connection electrode 930 and each terminal electrode 830R.

In addition, although the configuration in which the LED element 820R is provided on the semiconductor substrate 810 has been described above, the LED element 820R may be provided on a glass substrate or a resin substrate. That is, the LED element 820R can also be transferred using a glass substrate or a resin substrate as a carrier substrate.

In step S300 of FIG. 3, a light shielding mask 400 is placed on the element substrate 800 (see FIG. 4C). The light shielding mask 400 has a plurality of openings 400a. The plurality of openings 400a are arranged, for example, in accordance with the pitch (the interval between pixels) of pixels corresponding to red, pixels corresponding to green, or pixels corresponding to blue. In FIG. 4C, the opening 400a overlaps the position where the LED element 820R is arranged.

In step S400 in FIG. 3, the pressing jig 200 is placed on the light shielding mask 400 and presses the element substrate 800 through the light shielding mask 400 (see FIG. 4D). Thereby, the terminal electrode 830R of the LED element 820R and the connection electrode 930 can be brought into close contact with each other. Further, by pressing the pressing jig 200, the plate member 210 of the pressing jig 200, the light shielding mask 400, and the element substrate 800 are brought into close contact.

In step S500 in FIG. 3, the laser irradiation unit 300 irradiates the LED element 820 with the first laser beam 310 to collectively bond the connection electrode 930 and the LED element 820R (see FIG. 4E). This process is a process of melting and joining the connection electrode 930 and the terminal electrode 830R by irradiation with the first laser beam 310 . The first laser beam 310 is transmitted through the transmission region 230 of the pressing jig 200 and the opening 400 a of the light shielding mask 400 and is irradiated to the terminal electrode 830 of the LED element 820 .

As described above, the first laser beam 310 has a wavelength in the infrared region or near-infrared region and is absorbed by the terminal electrode 830 or the connection electrode 930 . By irradiation with the first laser beam 310, an alloy layer 940 made of a eutectic alloy is formed between the connection electrode 930 and the terminal electrode 830R. As described above, the connection electrode 930 is made of tin (Sn). On the other hand, the terminal electrode 830R is made of gold (Au). That is, as the alloy layer 940, a layer made of a Sn—Au eutectic alloy is formed. However, other metal materials may be used for the connection electrode 930 and the terminal electrode 830R as long as they can form a eutectic alloy with each other.

By forming an alloy layer 940 made of a eutectic alloy between the connection electrode 930 and the terminal electrode 830R, the connection electrode 930 and the terminal electrode 830R are joined via the alloy layer 940. As a result, the LED element 820R can be mounted firmly on the connection electrode 930. FIG.

In step S600 in FIG. 3, the laser irradiation unit 300 irradiates the LED elements 820 with the second laser beam 320 to collectively separate the semiconductor substrate 810 and the LED elements 820R (see FIG. 4F). This process is a so-called laser lift-off process. Specifically, it is a process of irradiating the second laser beam 320 to modify the boundary portions between the semiconductor substrate 810 and the plurality of LED elements 820R, thereby separating the plurality of LED elements 820R from the semiconductor substrate 810. FIG.

As described above, the second laser beam 320 has a wavelength in the ultraviolet region and is absorbed by the LED element 820 . The irradiation of the second laser beam 320 modifies the surface layer portion of the LED element 820R (the boundary portion with the semiconductor substrate 810) to separate the semiconductor substrate 810 and the LED element 820R.

After irradiation with the second laser beam 320, the semiconductor substrate 810 and each LED element 820R are separated. Through the above process, the LED element 820R can be mounted on the circuit board 900 as shown in FIG. 4G.

After obtaining the state shown in FIG. 4G, steps S200 to S600 shown in FIG. 3 are repeated to sequentially mount the green-emitting LED element 820G and the blue-emitting LED element 820B on the circuit board 900. .

Due to the irradiation of the first laser beam 310 in step S500 and the irradiation of the second laser beam 320 in step S600, the temperatures of the light shielding mask 400, the element substrate 800, and the circuit substrate 900 may rise. However, in the present embodiment, the pressing jig 200 is provided with a cooling portion (heat sink 220), and the plate member 210, the light shielding mask 400, the element substrate 800, and the circuit board 900 are brought into close contact with each other by pressing. The heat of the mask 400 , the element substrate 800 , and the circuit board 900 is conducted to the plate member 210 , and the heat sink 220 can absorb or dissipate the heat conducted to the plate member 210 . Therefore, the pressing jig 200 can suppress the temperature rise of the light shielding mask 400 , the element substrate 800 and the circuit substrate 900 . Therefore, in the transfer apparatus 10 including the pressing jig 200, the temperature rise of the light shielding mask 400, the element substrate 800, and the circuit board 900 can be suppressed. improves. Also, heat damage to the LED element 820 or the circuit board 900 can be reduced.

[3. Configuration of display device 20]
A display device 20 manufactured using the transfer device 10 according to one embodiment of the present invention will be described with reference to FIGS. 5 to 8. FIG.

[3-1. Outline of configuration of display device 20]
FIG. 5 is a plan view showing the outline of the configuration of the display device 20 manufactured using the transfer device 10 according to one embodiment of the present invention. As shown in FIG. 5, the display device 20 has a circuit board 900, a flexible printed circuit board 1010 (FPC 1010), and an IC chip 1020. FIG. Further, the display device 20 is divided into a display area 20a, a peripheral area 20b, and a terminal area 20c.

The display area 20a is an area in which a plurality of pixels including the LED elements 820 are arranged in the row direction (D1 direction) and the column direction (D2 direction). Specifically, pixels 950R including LED elements 820R, pixels 950G including LED elements 820G, and pixels 950B including LED elements 820B are arranged in the display area 20a. The display area 20a functions as an area for displaying an image according to the video signal.

The peripheral area 20b is an area around the display area 20a. The peripheral region 20b is a region provided with driver circuits (the data driver circuit 1030 and the gate driver circuit 1040 shown in FIG. 6) for controlling the pixel circuits 920 provided in the respective pixels 950. FIG.

The terminal area 20c is an area where a plurality of wirings connected to the driver circuit are concentrated. The flexible printed circuit board 1010 is electrically connected to a plurality of wirings in the terminal area 20c. A video signal (data signal) or a control signal output from an external device (not shown) is input to IC chip 1020 via wiring (not shown) provided on flexible printed circuit board 1010 . The IC chip 1020 performs signal processing on the video signal or generates control signals necessary for display control. A video signal and a control signal output from IC chip 1020 are input to display device 20 via flexible printed circuit board 1010 .

[3-2. Circuit configuration of display device 20]
FIG. 6 is a block diagram showing the circuit configuration of the display device 20 manufactured using the transfer device 10 according to one embodiment of the present invention. As shown in FIG. 6, a plurality of pixel circuits 920 are provided in the row direction (D1 direction) and column direction (D2 direction) corresponding to each pixel 950 in the display area 20a. That is, pixel circuits 920R, 920G and 920B are provided corresponding to the pixels 950R, 950G and 950B, respectively.

FIG. 7 is a circuit diagram showing the configuration of the pixel circuit 920 of the display device 20 manufactured using the transfer device 10 according to one embodiment of the present invention. The pixel circuits 920 are arranged in a region surrounded by data lines 921 , gate lines 922 , anode power lines 923 and cathode power lines 924 . Pixel circuit 920 includes select transistor 926 , drive transistor 927 , storage capacitor 928 and LED element 820 . Circuit elements other than the LED element 820 in the pixel circuit 920 are provided on the circuit board 900 . That is, the pixel circuit 920 is completed by mounting the LED element 820 on the circuit board 900 . However, in this specification, a circuit configuration that does not include the LED element 820 may be described as a pixel circuit 920 for convenience.

As shown in FIG. 7, the source, gate and drain electrodes of the selection transistor 926 are connected to the data line 921, the gate line 922 and the gate electrode of the drive transistor 927, respectively. The source electrode, gate electrode and drain electrode of the drive transistor 927 are connected to the anode power line 923, the drain electrode of the selection transistor 926 and the LED element 820, respectively. A storage capacitor 928 is connected between the gate electrode and the drain electrode of the drive transistor 927 . That is, the holding capacitor 928 is connected to the drain electrode of the selection transistor 926 . The anode and cathode of the LED element 820 are connected to the drain electrode of the drive transistor 927 and the cathode power supply line 924, respectively.

A gradation signal that determines the light emission intensity of the LED element 820 is supplied to the data line 921 . The gate line 922 is supplied with a gate signal for selecting a selection transistor 926 for writing a gradation signal. When the selection transistor 926 is turned on, the gradation signal is accumulated in the holding capacitor 928 . After that, when the driving transistor 927 is turned on, a driving current corresponding to the gradation signal flows through the driving transistor 927 . When the driving current output from the driving transistor 927 is input to the LED element 820, the LED element 820 emits light with an emission intensity corresponding to the gradation signal.

Referring to FIG. 6 again, a data driver circuit 1030 is arranged adjacent to the display area 20a in the column direction (D2 direction). A gate driver circuit 1040 is arranged at a position adjacent to the display area 20a in the row direction (D1 direction). Although two gate driver circuits 1040 are provided on both sides of the display area 20a in FIG. 6, they may be provided on only one side.

Data driver circuit 1030 and gate driver circuit 1040 are both arranged in peripheral region 20b. However, the area where the data driver circuit 1030 is arranged is not limited to the peripheral area 20b. For example, data driver circuitry 1030 may be located on flexible printed circuit board 1010 .

The data line 921 shown in FIG. 7 extends in the D2 direction from the data driver circuit 1030 and is connected to the source electrode of the select transistor 926 in each pixel circuit 920. The data line 921 shown in FIG. The gate line 922 extends from the gate driver circuit 1040 in the D1 direction and is connected to the gate electrode of the selection transistor 926 in each pixel circuit 920 .

A terminal portion 1050 is arranged in the terminal region 20c. The terminal section 1050 is connected to the data driver circuit 1030 via the connection wiring 1051 . Similarly, the terminal section 1050 is connected to the gate driver circuit 1040 via the connection wiring 1052 . Furthermore, the terminal portion 1050 is connected to the flexible printed circuit board 1010 .

[3-3. Cross-sectional structure of display device 20]
FIG. 8 is a cross-sectional view showing the configuration of a pixel 950 of the display device 20 manufactured using the transfer device 10 according to one embodiment of the present invention. A pixel 950 has a driving transistor 927 provided on a support substrate 910 .

The driving transistor 927 includes a semiconductor layer 927a, a gate insulating layer 927b, and a gate electrode 927c. A source electrode 927e and a drain electrode 927f are connected to the semiconductor layer 927a through an insulating layer 927d. Although not shown, the gate electrode 927c is connected to the drain electrode of the selection transistor 926 shown in FIG.

A wiring 961 is provided in the same layer as the source electrode 927e and the drain electrode 927f. The wiring 961 functions as the anode power supply line 923 shown in FIG. Therefore, the source electrode 927 e and the wiring 961 are electrically connected by a connection wiring 963 provided over the planarization layer 962 . The planarization layer 962 is a transparent resin layer using a resin material such as polyimide or acrylic. The connection wiring 963 is a transparent conductive layer using a metal oxide material such as ITO. However, not limited to this example, other metal materials can also be used as the connection wiring 963 .

An insulating layer 964 made of silicon nitride or the like is provided on the connection wiring 963 . An anode electrode 965 and a cathode electrode 966 are provided on the insulating layer 964 . In this embodiment, the anode electrode 965 and the cathode electrode 966 are transparent conductive layers using metal oxide materials such as ITO. The anode electrode 965 is connected to the drain electrode 927f through an opening provided in the planarizing layer 962 and the insulating layer 964. FIG.

Anode electrode 965 and cathode electrode 966 are connected to mounting pads 968a and 968b through planarization layer 967, respectively. Mounting pads 968a and 968b are made of, for example, a metal material such as tantalum or tungsten. Connection electrodes 930a and 930b are provided on the mounting pads 968a and 968b, respectively. Connection electrodes 930a and 930b correspond to connection electrode 930 shown in FIG. 4A. That is, electrodes made of tin (Sn) are arranged as connection electrodes 930a and 930b.

Terminal electrodes 830a and 830b of the LED element 820 are joined to the connection electrodes 930a and 930b, respectively. As described above, terminal electrodes 830a and 203b are electrodes made of gold (Au). Moreover, as described with reference to FIG. 4E, an alloy layer (not shown) (alloy layer 940 shown in FIG. 4E) exists between the connection electrode 930a and the terminal electrode 830a.

As shown in FIG. 7, the terminal electrode 830a of the LED element 820 is connected to the anode electrode 965 which is connected to the drain electrode 927f of the drive transistor 927. As shown in FIG. A terminal electrode 830 b of the LED element 820 is connected to the cathode electrode 966 . Cathode electrode 966 is electrically connected to cathode power line 924 shown in FIG.

Although the flip-chip type LED element 820 is shown in FIG. 8, a face-up type can also be used as the LED element 820 .

In the display device 20 manufactured using the transfer apparatus 10 according to the present embodiment, the LED element 820 is firmly mounted by pressing the pressing jig 200, and the LED element 820 or the LED element 820 is cooled by the pressing jig 200. Thermal damage to the circuit board 900 is reduced.

<Second embodiment>
A pressing jig 200A different from the pressing jig 200 of the transfer device 10 will be described with reference to FIGS. 9A and 9B. 9A and 9B are schematic perspective and cross-sectional views, respectively, of a pressing jig 200A according to one embodiment of the present invention. More specifically, FIG. 9B is a cross-sectional view of the pressing jig 200A cut along line A1-A2 shown in FIG. 9A. In addition, below, when the structure of 200 A of press jigs is the same as that of the structure of the press jig 200, the description may be abbreviate|omitted.

As shown in FIG. 9A, the pressing jig 200A includes a plate member 210 and a heat sink 220A. The heat sink 220</b>A is provided in contact with the plate-like member 210 in the peripheral portion of the plate-like member 210 . The heat sink 220A also includes an inlet hole 221A through which liquid is supplied and an outlet hole 222A through which liquid is discharged. Heat sink 220 is air-cooled while heat sink 220A is water-cooled. That is, in the pressing jig 200A, as shown in FIG. 9B, a flow path 223A is provided in the heat sink 220A, and the liquid supplied from the inlet hole 221A flows through the flow path 223A and is discharged from the outlet hole 222A. .

The liquid supplied to the heat sink 220A is, for example, water, but is not limited to this. The liquid supplied to the heat sink 220A may be fluorine-based coolant. Also, the liquid supplied to the heat sink 220A may be circulated using a chiller or pump.

In the pressing jig 200A, the liquid flowing inside the heat sink 220A can absorb the heat of the plate member 210 in contact with the heat sink 220A. That is, in the present embodiment, since the pressing jig 200A is provided with the cooling portion (heat sink 220A), the heat generated in the light-shielding mask 400, the element substrate 800, and the circuit substrate 900 due to the irradiation of the laser beam is transferred into a plate shape. The heat conducted to the member 210 can be absorbed or dissipated by the heat sink 220A. Therefore, the pressing jig 200A can suppress the temperature rise of the light shielding mask 400, the element substrate 800, and the circuit substrate 900. FIG. Therefore, by transferring the LED elements 820 from the element substrate 800 to the circuit board 900 using the pressing jig 200A, it is possible to suppress the temperature rise of the light-shielding mask 400, the element substrate 800, and the circuit board 900. The accuracy of transferring the LED element 820 with respect to the position of is improved. Also, heat damage to the LED element 820 or the circuit board 900 can be reduced.

<Third Embodiment>
Another pressing jig 200B will be described with reference to FIGS. 10A and 10B. 10A and 10B are schematic perspective and cross-sectional views, respectively, of a pressing jig 200B according to one embodiment of the present invention. More specifically, FIG. 10B is a cross-sectional view of the pressing jig 200B cut along line B1-B2 shown in FIG. 10A. In addition, below, when the structure of the pressing jig 200B is the same as the structure of the pressing jig 200, the description may be omitted.

As shown in FIG. 10A, the pressing jig 200B includes a plate member 210 and a heat sink 220B. The heat sink 220</b>B is provided in contact with the plate-like member 210 in the peripheral portion of the plate-like member 210 . As shown in FIG. 10B, the heat sink 220B is provided in the periphery of the plate-like member 210 so as to be in contact with not only the upper and lower surfaces but also the side surfaces. That is, since the heat sink 220B has a large area in contact with the plate-like member 210, heat conduction from the plate-like member 210 to the heat sink 220B is also large.

In this embodiment, since the pressing jig 200B is provided with a cooling portion (heat sink 220B), the heat generated in the light shielding mask 400, the element substrate 800, and the circuit substrate 900 due to the irradiation of the laser beam is transferred to the plate member 210. and the heat sink 220B can absorb or dissipate the heat conducted to the plate member 210. As shown in FIG. Therefore, the pressing jig 200B can suppress the temperature rise of the light shielding mask 400, the element substrate 800, and the circuit substrate 900. FIG. Therefore, by transferring the LED elements 820 from the element substrate 800 to the circuit substrate 900 using the pressing jig 200B, it is possible to suppress the temperature rise of the light shielding mask 400, the element substrate 800, and the circuit substrate 900. The accuracy of transferring the LED element 820 with respect to the position of is improved. Also, heat damage to the LED element 820 or the circuit board 900 can be reduced.

<Fourth Embodiment>
Still another pressing jig 200C will be described with reference to FIGS. 11A and 11B. 11A and 11B are schematic perspective and cross-sectional views, respectively, of a pressing jig 200C according to one embodiment of the present invention. More specifically, FIG. 11B is a cross-sectional view of the pressing jig 200C cut along line C1-C2 shown in FIG. 11A. In addition, below, when the structure of 200 C of press jigs is the same as that of the structure of the press jig 200, the description may be abbreviate|omitted.

As shown in FIG. 11A, the pressing jig 200C includes a plate member 210C. The plate member 210C includes an inlet hole 211C through which liquid is supplied and an outlet hole 212C through which liquid is discharged. That is, in the pressing jig 200C, as shown in FIG. 11B, a flow path 213C is provided in the plate member 210C, and the liquid supplied from the inlet hole 211C flows through the flow path 213C and exits from the outlet hole 212C. Ejected.

In the pressing jig 200C, the liquid flowing inside the plate-like member 210C can take heat from the plate-like member 210C. Therefore, in the present embodiment, the heat generated in the light-shielding mask 400, the element substrate 800, and the circuit substrate 900 due to the irradiation of the laser light is reduced by providing the cooling portion inside the plate-like member 210C of the pressing jig 200C. is conducted to the plate-like member 210C, and the cooling portion inside the plate-like member 210C can absorb or dissipate the conducted heat. Therefore, the pressing jig 200</b>C can suppress the temperature rise of the light shielding mask 400 , the element substrate 800 and the circuit substrate 900 . Therefore, if the LED elements 820 are transferred from the element substrate 800 to the circuit board 900 using the pressing jig 200C, the temperature rise of the light shielding mask 400, the element substrate 800, and the circuit board 900 can be suppressed. The accuracy of transferring the LED element 820 with respect to the position of is improved. Also, heat damage to the LED element 820 or the circuit board 900 can be reduced.

Each of the embodiments described above as embodiments of the present invention can be implemented in combination as appropriate as long as they do not contradict each other. Based on each embodiment, a person skilled in the art appropriately adds, deletes, or changes the design of components, or adds, omits, or changes the conditions of steps, and also includes the gist of the present invention. as long as they are within the scope of the present invention.

In addition, even if there are other effects that are different from the effects brought about by the aspects of the above-described embodiments, those that are obvious from the description of this specification or those that can be easily predicted by those skilled in the art are of course to the present invention.

10: Transfer device 20: Display device 20a: Display area 20b: Peripheral area 20c: Terminal area 100: Stage 200, 200A, 200B, 200C: Pressing jig 210, 210C: Plate member 211C: inlet hole 212C: outlet hole 213C: flow path 220, 220A, 220B: heat sink 221A: inlet hole 222A: outlet hole 223A: flow path 230: transmission region 300: laser irradiation section 310 : first laser light 320: second laser light 400: light shielding mask 400a: opening 800: element substrate 810: semiconductor substrate 820, 820B, 820G, 820R: LED elements 830, 830a, 830b, 830R: terminal electrode, 900: circuit board, 910: support substrate, 920, 920B, 920G, 920R: pixel circuit, 921: data line, 922: gate line, 923: anode power line, 924: cathode power line, 926: selection transistor 927: drive transistor 927a: semiconductor layer 927b: gate insulating layer 927c: gate electrode 927d: insulating layer 927e: source electrode 927f: drain electrode 928: storage capacitor 930: connection electrode 930a : Connection electrode 940: Alloy layer 950, 950B, 950G, 950R: Pixel 961: Wiring 962: Flattening layer 963: Connection wiring 964: Insulating layer 965: Anode electrode 966: Cathode electrode 967 : planarization layer 968a, 968b: mounting pad 1010: flexible printed circuit board (FPC) 1020: IC chip 1030: data driver circuit 1040: gate driver circuit 1050: terminal section 1051: connection wiring 1052 : Connection wiring

Claims (14)

A pressing jig for pressing an element substrate provided with LED elements against a circuit substrate provided with pixel circuits for driving the LED elements, the pressing jig comprising:
a plate-shaped member that transmits laser light irradiated to the LED element;
and a cooling part that cools the plate member. 2. The pressing jig according to claim 1, wherein said cooling portion is provided in a peripheral portion of said plate member. 3. The pressing jig according to claim 1, wherein said cooling part is a heat sink. 4. The pressing jig according to any one of claims 1 to 3, wherein said cooling unit is water-cooled. 2. The pressing jig according to claim 1, wherein said cooling portion is provided inside said plate member. The pressing jig according to any one of claims 1 to 5, wherein the plate member is quartz glass. a stage on which a circuit board provided with pixel circuits for driving LED elements is mounted;
a laser irradiation unit that irradiates the LED element with laser light;
A transfer device, comprising: a plate-shaped member that transmits the laser light; and a cooling unit that cools the plate-shaped member. 8. The transfer device according to claim 7, wherein said cooling unit is provided in a peripheral portion of said plate member. 9. The transfer device according to claim 7, wherein said cooling unit is a heat sink. The transfer device according to any one of claims 7 to 9, wherein the cooling unit is water-cooled. 8. The transfer device according to claim 7, wherein said cooling unit is provided inside said plate member. The transfer device according to any one of claims 7 to 11, wherein the plate member is quartz glass. 13. The transfer apparatus according to any one of claims 7 to 12, further comprising a patterned light shielding mask between said pressing jig and said element substrate. The transfer device according to any one of claims 7 to 13, wherein the laser irradiation unit irradiates two types of laser beams having different wavelengths.

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