Method for manufacturing element supply substrates, method for manufacturing electrical equipment, method for manufacturing electronic equipment, and 3D mounting method

Abstract

To provide a method for manufacturing a light emitting diode supply substrate, capable of manufacturing the light emitting diode supply substrate capable of transferring a plurality of normal light emitting diodes to a supply destination.SOLUTION: A method for manufacturing a light emitting diode supply substrate, capable of transferring a plurality of light emitting diodes comprises: a first mounting step of mounting a plurality of light emitting diodes on a supply substrate; a selection removal step of selectively removing a poor light emitting diode on the supply substrate; and a second mounting step of transferring a normal light emitting diode at a position having the poor light emitting diode arranged on the supply substrate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a light-emitting diode supply substrate, a method for manufacturing a light-emitting diode display, a method for manufacturing a divided unit of a light-emitting diode display, and a method for manufacturing an element supply substrate.

Background Art

[0002] In recent years, the development of displays using mini light-emitting diodes and micro light-emitting diodes has been actively carried out. One of the major manufacturing challenges for their practical application is the manufacturing means for arranging minute light-emitting diodes on a display panel. As an assembling means, a micro-structure transfer technique using a stamp has attracted attention (for example, Patent Document 1, Non-Patent Document 1).

[0003] When assembling a display panel of FHD (1920×1080) using this technique, if light-emitting diodes are transferred one by one from a light-emitting diode supply substrate, transfer for 2,073,600 pixels is required. When manufacturing a color display, transfer of at least three types of mini light-emitting diodes or micro light-emitting diodes of red (R), green (G), and blue (B) is required for one pixel. If transferred one element at a time, transfer of about six million times or more is required. In the case of a 4K display, a transfer operation of 24 million times or more is required. Even if the display is assembled with such labor, when using a supply substrate containing a large number of defective light-emitting diodes, there is a problem that normal light-emitting diodes must be rearranged, that is, repaired, on the display panel substrate. Therefore, a supply substrate on which only normal light-emitting diodes are mounted is eagerly desired. Note that this problem is an essential common problem even when transferring in a batch from the supply substrate to the display panel substrate.

[0004] As a faster and more efficient transfer method than the stamping method, there is the laser lift-off method. Patent document 2 describes a method in which a release layer is provided between the microfunctional element to be transferred and the substrate, and the release layer is ablated when a laser is irradiated to separate the substrate from the element. The disadvantage of using this method is that the material of the release layer adheres to the side of the microfunctional element, so cleaning after transfer is necessary, and it is not necessarily a good method. As a method that does not use a release layer, there is a method that utilizes the pressure-sensitive adhesion of the silicone resin PDMS (PolyDiMethylSiloxane) (Patent document 3, Non-patent document 2). When this method is used, no unnecessary deposits adhere to the microfunctional element after it has been laser lifted off, so expectations for the laser lift-off method using silicone resin are increasing. An example of an apparatus for transferring microfunctional elements by the laser lift-off method is shown in Patent document 4.

[0005] The following describes an example of a conventional method for manufacturing a light-emitting diode (LED) display panel using the laser lift-off method described above, with reference to Figure 9. Figures 9(I) to (III) show an example of the process for manufacturing a supply substrate from an LED manufacturing substrate, and the process of transferring LEDs one by one to the display panel substrate using the stamping method described above is shown in Figures 9(IV) and (V).

[0006] In Figure 9(I), 1 is a sapphire substrate as a starting substrate, and multiple GaN-based light-emitting diodes 2 are processed on one surface thereof in a state where they are individually separated. Furthermore, each light-emitting diode 2 is equipped with an electrode 3. 4 is the first supply substrate, which consists of a substrate 41 made of quartz and a silicone resin layer 42 formed thereon as an adhesive layer.

[0007] As shown in Figure 9(I), the first supply substrate 4 and the starting substrate (sapphire substrate) 1 are positioned at an optimal distance from each other so that the light-emitting diodes 2 face the adhesive layer 42 and the gap between them remains constant. In this state, a laser beam 6 is shone from the surface of the starting substrate 1 where the light-emitting diodes 2 are not formed. The laser beam 6 passes through the starting substrate 1 and reaches the vicinity of the interface between the surface of the starting substrate 1 and the light-emitting diodes 2, causing a thin laser ablation of the GaN on the light-emitting diode 2 side near this interface. This is known as laser lift-off, and the light-emitting diodes 2 are separated from the starting substrate 1 and emitted toward the opposing first supply substrate 4. As a result, the emitted light-emitting diodes 2 fly to the surface of the adhesive layer (silicone resin layer) 42 and are temporarily adhered to the surface of the adhesive layer 42. By scanning a desired area of ​​the starting substrate 1 with the laser beam 6, all the desired light-emitting diodes 2 on the starting substrate 1 can be transferred to the first supply substrate 4, completing the first supply substrate 4 shown in Figure 9(II). In this case, since the GaN components do not adhere to the light-emitting diode 2 as residue due to ablation, there is no need to wash away some of the deposits in the release layer, as is the case with a release layer (containing an organic polymer).

[0008] Next, as shown in Figure 9(III), a second supply substrate 5 is prepared, which has a substrate 51 and a silicone resin layer 52 on top of it as an adhesive layer. Then, this second supply substrate 5 and the first supply substrate 4 shown in Figure 9(II) are placed at an optimal distance apart so that the light-emitting diode 2 faces the adhesive layer 52, and the gap between them remains constant.

[0009] In this state, by scanning and irradiating a desired area of ​​the surface of the first supply substrate 4 where the light-emitting diode 2 is not placed with laser light 6, a second supply substrate 5 is completed in which the light-emitting diode 2 equipped with electrodes 3 is temporarily bonded in an inverted state. In this way, a second supply substrate 5 can be manufactured as a light-emitting diode supply substrate with electrodes 3 facing outwards.

[0010] Next, a display panel substrate 39, which will serve as the supply destination, is prepared as shown in Figure 9(IV). The display panel substrate 39 is equipped with electrodes and wiring, although not shown. The display panel substrate 39 and the second supply substrate 5 are placed at an optimal distance apart so that the gap between them remains constant. In this state, laser light 6 is shone from the side of the second supply substrate 5 where no light-emitting diodes 2 are placed. Using this laser lift-off method, multiple light-emitting diodes 2 are transferred from the second supply substrate 5 to the display panel substrate 39, as shown in Figure 9(V).

[0011] By using the laser lift-off method in this way, the display panel 300 is completed by positioning the electrodes 3 of the light-emitting diodes 2 so that they make electrical contact with the desired electrode positions on the display panel substrate 39 (Figure 9(V)).

[0012] However, even when manufacturing displays using the laser lift-off method, which allows for faster transfer than the stamping method, a problem remains: if a supply board containing a large number of defective LEDs is used, the normal LEDs must be rearranged, i.e., repaired, on the display board. Therefore, supply boards containing only normal LEDs are highly desired. [Prior art documents] [Patent Documents]

[0013] [Patent Document 1] U.S. Patent No. 7943491 [Patent Document 2] Patent No. 5319533 [Patent Document 3] U.S. Patent No. 9555644 [Patent Document 4] Japanese Patent Publication No. 2020-4478 [Non-patent literature]

[0014] [Non-Patent Document 1] Matthew A. Meitl, Zheng-Tao Zhu, Vipan Kumar, Keon Jae Lee, Xue Feng, Yonggang Y. Huang, Ilesanmi Adesida, Ralph G. Nuzzo & John A. Rogers, “Transfer printing by kinetic control of adhesion to an elastomeric stamp”, Nature Materials, Volume 5, 33-38 (2006) [Non-Patent Document 2] Kristin M. Charipar, Raymond CY Auyeung, Heungsoo Kim, Nicholas A. Charipar and Alberto Pique, “Use of an Elastomeric Donor for LIFT of Metal Foils”, JLMN-Journal of Laser Micro / Nanoengineering, Vol. 13, No. 2, 2018. [Overview of the Initiative] [Problems that the invention aims to solve]

[0015] As explained above, in both the stamping method and the laser lift-off method, if a defective light-emitting diode is included in the supply substrate (second supply substrate 5 in Figure 9) that supplies light-emitting diodes to the display panel substrate, the defective light-emitting diode will be transferred directly to the display panel substrate, resulting in a problem of reduced normal transfer yield.

[0016] The present invention is made to solve the above problems, and aims to provide a method for manufacturing a light-emitting diode supply substrate capable of transferring a plurality of normal light-emitting diodes to a supply destination, a method for manufacturing a high-yield light-emitting diode display, a method for manufacturing a dividing unit of a high-yield light-emitting diode display, and a method for manufacturing an element supply substrate capable of transferring a plurality of normal elements to a supply destination.

Means for Solving the Problems

[0017] In order to solve the above problems, the present invention provides a method for manufacturing a light-emitting diode supply substrate for transferring a plurality of light-emitting diodes to a supply destination, comprising: a first mounting step of mounting a plurality of light-emitting diodes on a supply substrate; a selective removal step of selectively removing defective light-emitting diodes on the supply substrate; a second mounting step of transferring normal light-emitting diodes to positions where the defective light-emitting diodes on the supply substrate were disposed. The method for manufacturing a light-emitting diode supply substrate is characterized by including the above steps.

[0018] By doing so, a light-emitting diode supply substrate equipped only with normal light-emitting diodes can be manufactured. By using the light-emitting diode supply substrate manufactured in this way, a plurality of normal light-emitting diodes can be transferred to a supply destination collectively or selectively. That is, according to the method for manufacturing a light-emitting diode supply substrate of the present invention, a light-emitting diode supply substrate capable of transferring a plurality of normal light-emitting diodes to a supply destination collectively or selectively can be manufactured.

[0019] In addition, since the light-emitting diode supply substrate manufactured by the method for manufacturing a light-emitting diode supply substrate of the present invention does not include defective light-emitting diodes, the occurrence of light-emitting defects during the manufacture of a light-emitting diode display or a divided unit of a light-emitting diode display can be significantly reduced. As a result, it becomes possible to manufacture a light-emitting diode display or a divided unit thereof with a high yield and high efficiency.

[0020] It is preferable to further include a determination step of determining whether each of the light-emitting diodes on the supply substrate is normal before the selective removal step.

[0021] By doing so, defective light-emitting diodes can be surely sorted and removed.

[0022] In addition, it is preferable to perform the determination step by a photoluminescence method.

[0023] When the determination step is performed by a photoluminescence method, it can be determined non-contact.

[0024] It is preferable to perform the selective removal step, the second mounting step, or both by a laser lift-off method.

[0025] If the selective removal step, the second mounting step, or both are performed by a laser lift-off method, a light-emitting diode supply substrate can be manufactured with higher efficiency.

[0026] It is preferable that the laser used in the laser lift-off method in the selective removal step, the second mounting step, or both is an excimer laser.

[0027] By doing so, time-compressed pulsed laser light can be generated. The pulse width and light intensity can be easily controlled by controlling device power parameters such as the pulse transmission voltage, and it is possible to generate high-intensity laser light with a single pulse, which cannot be achieved by other continuous wave oscillation (CW) lasers.

[0028] The laser used in the laser lift-off method in the selective removal step, the second mounting step, or both thereof is a pulsed laser, and lift-off is performed by irradiating with one pulse of laser light.

[0029] In this way, the laser used in the selective removal step, the second mounting step, or both is not limited to an excimer laser, and any laser capable of generating pulsed laser light of the required intensity can be used.

[0030] It is preferable to use a light-emitting diode whose longest part is less than 300 μm.

[0031] This approach allows for more efficient transfer using the laser lift-off method.

[0032] As the light-emitting diode, one type selected from the group consisting of red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes can be used.

[0033] In this way, single-color supply substrates for red, green, and blue light-emitting diodes can be manufactured.

[0034] The plurality of light-emitting diodes can also be arranged such that one or more red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes form a set of pixels.

[0035] This approach allows for the transfer of LEDs in batches or pixel by pixel during the manufacturing process of light-emitting diode displays.

[0036] As the supply substrate, one is used that includes a quartz substrate and an adhesive layer provided on the quartz substrate. In the first mounting step, it is preferable to adhere the plurality of light-emitting diodes in a matrix shape to the surface of the adhesive layer of the supply substrate.

[0037] This method allows for the efficient manufacturing of supply substrates for light-emitting diodes.

[0038] The second mounting process is performed as follows: A replacement substrate is prepared, which includes a quartz substrate, an adhesive layer provided on the quartz substrate, and a plurality of light-emitting diodes adhered in a matrix pattern to the surface of the adhesive layer. The normal light-emitting diode on the replacement substrate is moved to the position on the supply substrate where the defective light-emitting diode was removed. It is preferable to do so.

[0039] This method allows for more efficient manufacturing of LED supply substrates.

[0040] Preferably, the selection and removal step and the second mounting step further include a placement step in which the replenishment substrate is positioned facing the supply substrate.

[0041] This approach allows for further improvement in the accuracy of the second mounting process.

[0042] In this case, it is preferable that, during the placement process, the position of the defective light-emitting diode on the supply substrate and the position of the normal light-emitting diode on the replacement substrate are aligned opposite each other.

[0043] This allows for more accurate placement of a working LED in the location where the defective LED was removed.

[0044] It is preferable to use a quartz substrate made of synthetic quartz as the supply substrate.

[0045] Synthetic quartz exhibits excellent in-plane film thickness uniformity. Therefore, using synthetic quartz as the quartz substrate makes it possible to control the gap between opposing substrates for laser lift-off methods.

[0046] It is preferable that the quartz substrate of the replenishment substrate also be made of synthetic quartz. In this case, for example, when the replenishment substrate is placed parallel to the supply substrate in the placement process, it can be placed at a constant distance with high precision across the entire surface of the substrate.

[0047] As the supply substrate, it is preferable to use one in which facets are provided on the quartz substrate.

[0048] This method ensures that when setting the supply substrate into a transfer device using the laser lift-off method, the rotational position can be set correctly without error.

[0049] In this case, it is more preferable to use a quartz substrate with facets provided as the supplementary substrate.

[0050] In this case, it is even more preferable that the facet is an indicator of orientation.

[0051] In this case, when setting the supply substrate into the transfer device using the laser lift-off method, it is possible to set it without making a mistake in the rotation position.

[0052] As the supply substrate, a quartz substrate having one or more selected from the group consisting of characters, symbols, and 2D barcodes can be used.

[0053] As the supplementary substrate, a quartz substrate having one or more selected from the group consisting of characters, symbols, and 2D barcodes may also be used.

[0054] This allows for the management of individual supply boards and replenishment boards.

[0055] The aforementioned characters, symbols, and 2D barcodes may be indicators of orientation.

[0056] The aforementioned characters, symbols, and 2D barcodes can be used to identify individual supply boards. They can also be used as indicators of orientation.

[0057] In this case, when setting the supply substrate into the transfer device using the laser lift-off method, individual substrates can be accurately identified, and the substrates can be set without making mistakes in their rotational position.

[0058] It is preferable to use a supply substrate in which the adhesive layer is made of a pressure-sensitive adhesive containing silicone.

[0059] As the replacement substrate, one in which the adhesive layer is made of a pressure-sensitive adhesive containing silicone can also be used.

[0060] This provides excellent adhesion. Furthermore, impurities do not adhere to the light-emitting diodes (LEDs) when they are transferred using the laser lift-off method. Additionally, the LEDs can be reattached after being removed.

[0061] As the supply substrate, it is preferable to use one in which the pitch of the matrix is ​​equal to or equal to one integer fraction of the pixel pitch of the display panel.

[0062] In this way, multiple light-emitting diodes can be transferred using the laser lift-off method by controlling the laser irradiation position while performing only minimal movement without unnecessary alignment movements of the supply substrate.

[0063] The first mounting process is, A starting substrate is a starting substrate on which the plurality of light-emitting diodes are manufactured, and a step of preparing a starting substrate is a starting substrate on which the plurality of light-emitting diodes are manufactured, A step of separating the plurality of light-emitting diodes on the starting substrate into individual elements, A step of transferring the plurality of light-emitting diodes, each separated into individual elements, onto the supply substrate. It is preferable that it includes.

[0064] This allows the first loading process to be carried out efficiently.

[0065] It is preferable that the step of transferring the plurality of light-emitting diodes onto the supply substrate in the first mounting step be performed by the laser lift-off method.

[0066] This allows the first loading process to be carried out even more efficiently.

[0067] Furthermore, the present invention relates to a method for manufacturing a light-emitting diode display, The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a display panel substrate. The present invention provides a method for manufacturing a light-emitting diode display, characterized by having the following features:

[0068] In the present invention's method for manufacturing a light-emitting diode display, a light-emitting diode supply substrate is manufactured using the present invention's method for manufacturing a light-emitting diode supply substrate, and multiple light-emitting diodes are transferred to a light-emitting diode display substrate using this substrate. This allows for the efficient manufacture of light-emitting diode displays that do not contain defective light-emitting diodes. In other words, the present invention's method for manufacturing a light-emitting diode display enables the manufacture of light-emitting diode displays with a high yield.

[0069] It is preferable to perform the step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto the display panel substrate by a laser lift-off method.

[0070] This method allows for faster transfer of multiple light-emitting diodes, thus providing a more practical method for manufacturing light-emitting diode displays.

[0071] Furthermore, the present invention relates to a method for manufacturing a divided unit of a light-emitting diode display, The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a divided unit of a light-emitting diode display. The present invention provides a method for manufacturing a divided unit of a light-emitting diode display, characterized by having [a specific feature].

[0072] In the method for manufacturing a divided unit of a light-emitting diode display according to the present invention, a light-emitting diode supply substrate is manufactured using the method for manufacturing a light-emitting diode supply substrate according to the present invention, and a plurality of light-emitting diodes are transferred to the divided unit of the light-emitting diode display using this substrate. This allows for the efficient manufacture of divided units of a light-emitting diode display that do not contain defective light-emitting diodes. In other words, according to the method for manufacturing a divided unit of a light-emitting diode display according to the present invention, divided units of a light-emitting diode display can be manufactured with a high yield.

[0073] It is preferable to perform the step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto the divided unit of the light-emitting diode display by a laser lift-off method.

[0074] This method allows for faster transfer of multiple light-emitting diodes, thus providing a more practical method for manufacturing segmented units of light-emitting diode displays.

[0075] Furthermore, the present invention relates to a method for manufacturing an element supply substrate for transferring multiple elements to a supply destination, A first mounting process involves mounting multiple elements onto a supply substrate, A selective removal step for selectively removing defective elements on the supply substrate, A second mounting step involves transferring a normal element to the position on the supply board where the defective element was located. The present invention provides a method for manufacturing an element supply substrate, characterized by including the following:

[0076] The present invention is not limited to a supply substrate for transferring light-emitting diodes, but can also provide an element supply substrate for transferring elements such as micro-electrical elements or micro-semiconductor chips. This element supply substrate can transfer multiple normal elements to a destination. A manufacturing method for such an element supply substrate can be used, for example, in 3D packaging and the manufacturing of electrical and electronic equipment.

[0077] For example, the element can be an electrical element, a semiconductor chip, or a MEMS element.

[0078] Thus, the method for manufacturing an element supply substrate according to the present invention can be applied to the supply of various elements. [Effects of the Invention]

[0079] As described above, the method for manufacturing a light-emitting diode supply substrate of the present invention makes it possible to manufacture a light-emitting diode supply substrate on which multiple normal light-emitting diodes can be transferred to a supply destination all at once or selectively.

[0080] Furthermore, since the light-emitting diode supply substrate manufactured by the manufacturing method of the present invention does not contain defective light-emitting diodes, the occurrence of light-emitting defects when manufacturing light-emitting diode displays or segmented units of light-emitting diode displays can be significantly reduced. As a result, it becomes possible to manufacture light-emitting diode displays with high yield and high efficiency.

[0081] Furthermore, since the method for manufacturing a light-emitting diode display and the method for manufacturing a divided unit of a light-emitting diode display according to the present invention include the method for manufacturing a light-emitting diode supply substrate according to the present invention, a light-emitting diode display or a divided unit of a light-emitting diode display that does not contain defective light-emitting diodes can be manufactured efficiently.

[0082] Furthermore, according to the method for manufacturing an element supply substrate of the present invention, it is possible to manufacture an element supply substrate that can transfer multiple normal elements to a supply destination all at once or selectively. [Brief explanation of the drawing]

[0083] [Figure 1] This is an explanatory diagram showing a part of the first embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 2] This is an explanatory diagram showing another part of the first embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 3] These are explanatory diagrams showing a part of an example of a manufacturing method for a light-emitting diode display, using a light-emitting diode supply substrate manufactured by the manufacturing method shown in Figures 1 and 2. [Figure 4] This is an explanatory diagram showing a part of a second embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 5] This is an explanatory diagram showing another part of the second embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 6] This is an explanatory diagram showing a part of a third embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 7] This is an explanatory diagram showing a part of the fourth embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 8] This is an explanatory diagram showing a part of the fifth embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention. [Figure 9] This is an explanatory diagram showing an example of a conventional method for manufacturing a light-emitting diode supply substrate and an example of a method for manufacturing a light-emitting diode display. [Modes for carrying out the invention]

[0084] As described above, there was a need for the development of a method for manufacturing an LED supply substrate that can produce an LED supply substrate on which multiple normal LEDs can be transferred to a supplier all at once or selectively; a method for manufacturing a high-yield LED display; a method for manufacturing a segmented unit of a high-yield LED display; and a method for manufacturing an element supply substrate that can produce an element supply substrate on which multiple normal elements can be transferred to a supplier all at once or selectively.

[0085] As a result of diligent research into the above-mentioned problems, the inventors of the present invention have found that a method for manufacturing a light-emitting diode supply substrate, which includes a selective removal step for selectively removing defective light-emitting diodes and a second mounting step for transferring normal light-emitting diodes to the positions where the defective light-emitting diodes were located, can solve the above-mentioned problems, and have completed the present invention.

[0086] In other words, the present invention is a method for manufacturing a light-emitting diode supply substrate for transferring a plurality of light-emitting diodes to a supply destination, A first mounting process involves mounting multiple light-emitting diodes onto a supply substrate, A selective removal step for selectively removing defective light-emitting diodes on the supply substrate, A second mounting step involves transferring a normal light-emitting diode to the position on the supply substrate where the defective light-emitting diode was located. This is a method for manufacturing a light-emitting diode supply substrate, characterized by including the following:

[0087] Furthermore, the present invention relates to a method for manufacturing a light-emitting diode display, The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a display panel substrate. This is a method for manufacturing a light-emitting diode display, characterized by having [a specific feature].

[0088] Furthermore, the present invention relates to a method for manufacturing a divided unit of a light-emitting diode display, The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a divided unit of a light-emitting diode display. This is a method for manufacturing a divided unit of a light-emitting diode display, characterized by having [a specific feature].

[0089] Furthermore, the present invention relates to a method for manufacturing an element supply substrate for transferring multiple elements to a supply destination, A first mounting process involves mounting multiple elements onto a supply substrate, A selective removal step for selectively removing defective elements on the supply substrate, A second mounting step involves transferring a normal element to the position on the supply board where the defective element was located. This is a method for manufacturing an element supply substrate, characterized by including [a specific element].

[0090] The present invention will be described in detail below, but the present invention is not limited to these descriptions.

[0091] [Manufacturing method for light-emitting diode supply substrate] The present invention relates to a method for manufacturing a light-emitting diode supply substrate for transferring a plurality of light-emitting diodes to a supply destination, A first mounting process involves mounting multiple light-emitting diodes onto a supply substrate, A selective removal step for selectively removing defective light-emitting diodes on the supply substrate, A second mounting step involves transferring a normal light-emitting diode to the position on the supply substrate where the defective light-emitting diode was located. It is characterized by including.

[0092] In the manufacturing method of a light-emitting diode supply substrate of the present invention, in the selective removal step, defective light-emitting diodes are selected from among the multiple light-emitting diodes placed on the supply substrate in the first mounting step and removed. Then, in the second mounting step, normal light-emitting diodes are transferred to the positions where the previously removed defective light-emitting diodes were located. With this manufacturing method, a light-emitting diode supply substrate containing only normal light-emitting diodes can be manufactured. By using the light-emitting diode supply substrate manufactured in this way, multiple normal light-emitting diodes can be transferred to the supply destination all at once or selectively by the laser lift-off method or the stamping method. In other words, the manufacturing method of a light-emitting diode supply substrate of the present invention makes it possible to manufacture a light-emitting diode supply substrate that can transfer multiple normal light-emitting diodes to the supply destination all at once. Furthermore, it is possible to select a light-emitting diode at a desired position on the light-emitting diode supply substrate manufactured according to the present invention and transfer a normal light-emitting diode to the supply destination by the laser lift-off method. In other words, it is possible to manufacture a light-emitting diode supply substrate that can transfer normal light-emitting diodes regardless of the position selected.

[0093] Furthermore, since the light-emitting diode supply substrate manufactured by the manufacturing method of the present invention does not contain defective light-emitting diodes, the occurrence of light-emitting defects during the manufacturing of light-emitting diode displays or segmented units of light-emitting diode displays can be significantly reduced. As a result, it becomes possible to manufacture light-emitting diode displays or their segmented units with high yield and high efficiency.

[0094] Next, we will explain each step in more detail.

[0095] [First loading process] In the first mounting process, multiple light-emitting diodes are mounted on the supply substrate.

[0096] As the supply substrate used here, for example, one can be used that includes a quartz substrate and an adhesive layer provided on the quartz substrate. Details of the supply substrate, quartz substrate, and adhesive layer will be described later.

[0097] As the light-emitting diode, one type selected from the group consisting of red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes can be used. In this way, single-color supply substrates for red, green, and blue light-emitting diodes can be manufactured.

[0098] For the light-emitting diode, it is preferable to use one with a longest part smaller than 300 μm. This reduces the inertial mass of the light-emitting diode, allowing for more efficient transfer using the laser lift-off method.

[0099] In the first mounting process, it is preferable to adhere multiple light-emitting diodes in a matrix pattern to the surface of the adhesive layer of the supply substrate. This method allows for the efficient manufacturing of supply substrates for light-emitting diodes.

[0100] In this case, it is preferable to use a matrix whose pitch is equal to or an integer fraction of the pixel pitch of the display panel.

[0101] In this way, by performing only minimal movement without unnecessary alignment movements of the supply substrate and controlling the laser irradiation position, multiple light-emitting diodes can be transferred simultaneously using the laser lift-off method.

[0102] The first loading process is, A starting substrate is a starting substrate on which the plurality of light-emitting diodes are manufactured, and a step of preparing a starting substrate is a starting substrate on which the plurality of light-emitting diodes are manufactured, A step of separating the plurality of light-emitting diodes on the starting substrate into individual elements, A step of transferring the plurality of light-emitting diodes, each separated into individual elements, onto the supply substrate. It is preferable that it includes. This allows the first loading process to be carried out efficiently.

[0103] Here, as the starting substrate, for example, one can be used that includes a sapphire substrate and a plurality of light-emitting diodes manufactured on this sapphire substrate.

[0104] It is preferable to perform the step of transferring the plurality of light-emitting diodes in the first mounting step by the laser lift-off method. This allows the first loading process to be carried out even more efficiently.

[0105] [Selection and Removal Process] In the selective removal process, defective light-emitting diodes on the supply substrate are selectively removed.

[0106] It is preferable to further include a determination step before the selective removal step to determine whether or not each light-emitting diode on the supply substrate is normal. This method allows for more reliable removal of defective light-emitting diodes during the selective removal process.

[0107] In this determination process, information about the location of the defective light-emitting diode may be recorded, for example, by mapping.

[0108] Furthermore, it is preferable to perform the determination process by photoluminescence. If the determination process is performed using the photoluminescence method, the determination can be made without contact.

[0109] Photoluminescence is a method that involves irradiating a material with light and observing the light emitted when excited electrons return to their ground state. The observed light information can be used to determine whether a material or electronic device of a functional element is normal or abnormal. For example, in the case of light-emitting diodes, TASMIT's INSPECTRA PL series is an example.

[0110] While photoluminescence is preferred because it is non-contact and offers fast determination speed, other methods may be used if they are preferable to photoluminescence for determining whether an object is normal or abnormal. When dealing with materials other than light-emitting diodes, or electronic devices such as functional elements, a method suitable for the object being determined should be used.

[0111] The selective removal process is preferably carried out by the laser lift-off method. By performing the selective removal process using the laser lift-off method, only the defective light-emitting diodes of the target can be easily removed, resulting in the more efficient manufacturing of light-emitting diode supply substrates.

[0112] When the selective removal process is performed by the laser lift-off method, it is preferable to shape the laser beam to approximately the same size as the defective light-emitting diode near the interface between the defective light-emitting diode and the adhesive layer of the supply substrate. In this way, each defective light-emitting diode can be selectively lifted off with a laser and removed.

[0113] Furthermore, by scanning the laser beam and directing it to a different light-emitting diode position at each irradiation timing, it is possible to selectively laser-lift off defective light-emitting diodes in the target.

[0114] The laser beams that can be used in the laser lift-off method during the selective removal process will be described later.

[0115] [Second loading process] In the second mounting process, a normal light-emitting diode is transferred to the location where a defective light-emitting diode was located on the supply substrate.

[0116] The second loading process is as follows: A replacement substrate is prepared, which includes a quartz substrate, an adhesive layer provided on the quartz substrate, and a plurality of light-emitting diodes adhered in a matrix pattern to the surface of the adhesive layer. The normal light-emitting diode on the replacement substrate is moved to the position on the supply substrate where the defective light-emitting diode was removed. It is preferable to do so. This method allows for more efficient manufacturing of LED supply substrates.

[0117] Alternatively, the replacement substrate can be, for example, one that includes a sapphire substrate similar to the starting substrate, and multiple light-emitting diodes manufactured on this sapphire substrate.

[0118] Preferably, the process further includes a placement step between the selective removal step and the second mounting step, in which the replenishment substrate is positioned facing the supply substrate. This approach allows for further improvement in the accuracy of the second mounting process.

[0119] In this case, it is preferable that in the above arrangement step, the positions of the defective light-emitting diodes on the supply substrate and the positions of the normal light-emitting diodes on the replacement substrate are aligned opposite each other. This allows for more accurate placement of a working LED in the location where the defective LED was removed.

[0120] The second mounting process is preferably carried out by the laser lift-off method. By performing the second mounting process using the laser lift-off method, only the normal light-emitting diodes of the target can be selected and easily transferred to the positions where the defective light-emitting diodes were located. As a result, the light-emitting diode supply substrate can be manufactured with higher efficiency.

[0121] When the second mounting process is performed by the laser lift-off method, it is preferable to shape the laser beam to approximately the same size as the normal light-emitting diode being transferred, near the interface between the normal light-emitting diode to be transferred and the adhesive layer of the replacement substrate. In this way, each normal light-emitting diode can be selectively lifted off with a laser, and the normal light-emitting diode can be moved more accurately to the position where the defective light-emitting diode was located.

[0122] Furthermore, by scanning the laser beam and directing it to a different light-emitting diode position at each irradiation timing, it is possible to selectively laser-lift off the normal light-emitting diodes of the target.

[0123] The laser beam that can be used in the laser lift-off method during the second mounting process will be described later.

[0124] In the method for manufacturing a light-emitting diode supply substrate of the present invention, the substrate obtained in the second mounting step may be used as the light-emitting diode supply substrate as is. Alternatively, multiple light-emitting diodes may be transferred from one or more substrates obtained in the second mounting step to another substrate, and the resulting substrate may be used as the light-emitting diode supply substrate. Specific examples of each will be described later.

[0125] Next, the supply substrate, optional replenishment substrate, laser light, and light-emitting diode that can be used in the manufacturing method of the light-emitting diode supply substrate of the present invention will be described in more detail.

[0126] [Supply board] The planar shape of the supply board may be circular or rectangular. Of course, the optimal shape should be used depending on the purpose. If it is simply to be used as a supply board for normal light-emitting diodes, the most efficient way to provide a supply board for light-emitting diodes is to use a circular supply board that inherits the pattern layout used during light-emitting diode manufacturing. On the other hand, if the focus is on providing a supply board for light-emitting diodes to manufacture a final display, then a supply board shape corresponding to divided units, so-called tiles, which are divided into integer fractions in both the vertical and horizontal directions while maintaining the desired display screen (shape, aspect ratio), is preferable. In this way, it is preferable to provide a supply board in a shape suitable for the final electronic device or other product to be manufactured.

[0127] Next, we will describe in more detail the quartz substrate and adhesive layer that can be used with the supply substrate and any replacement substrate.

[0128] [Quartz substrate] Using a substrate containing a quartz substrate as both the supply substrate and an optional replenishment substrate provides high transmittance of short-wavelength UV laser light that causes laser ablation. Preferably, the quartz substrate is a synthetic quartz substrate.

[0129] In the case of synthetic quartz glass, it is possible to achieve in-plane film thickness uniformity (TTV: total thickness variation) of approximately 1 μm or less. Therefore, by using synthetic quartz glass, it becomes possible to control the gap between opposing substrates for the laser lift-off method.

[0130] Furthermore, a benefit of using synthetic quartz glass is the improved thermal stability it provides. Specifically, synthetic quartz glass substrates have approximately one-fifth the coefficient of thermal expansion compared to other quartz glass substrates, reducing thermal strain during operation. In particular, for stamp components with convex-shaped protrusions, the reduction in displacement and distortion of the protrusions due to thermal expansion and contraction enables accurate laser lift-off transfer operations.

[0131] Furthermore, it is preferable to provide facets on at least one vertex on either the front or back surface of the quartz substrate, or to mark the orientation of the quartz substrate on the front, back, or side surface of the peripheral area of ​​the quartz substrate. In this way, when setting the supply substrate into a transfer device using the laser lift-off method, it is possible to set it in the correct rotational position without making a mistake.

[0132] Furthermore, the engraving of letters, symbols, or 2D barcodes on the quartz substrate allows for the management of individual supply substrates. These letters, symbols, or 2D barcodes may also be used as orientation indicators. The aforementioned facets may also be used as orientation indicators.

[0133] [Adhesive layer] For the adhesive layer, it is preferable to use a pressure-sensitive adhesive (silicone-based) mainly composed of silicone that does not cause ablation at the interface. As the silicone-based pressure-sensitive adhesive, PDMS (Polydimethylsiloxane), silicone compositions in which the side chains and both ends of PDMS have been modified, and compositions consisting of combinations thereof may be used. By adjusting the composition of each material (molecular weight, modifying group, modifying substance, amount of modification, etc.) and, in the case of mixtures, the mixing ratio, etc., the physical properties of the material such as hardness, pressure adhesion, and repeated adhesion can be controlled. In addition to mixing, various modified silicone compositions can also be optimized by crosslinking them or creating a three-dimensional molecular structure. When a silicone-based pressure-sensitive adhesive is optimized and used in the process of the present invention, unlike when using organic materials, such as polyimide or acrylic pressure-sensitive adhesives, or organic compositions whose main chain mainly consists of an organic skeleton, as the adhesive layer, the organic adhesive layer will not remain attached to the light-emitting diode when the light-emitting diode is peeled off from the adhesive layer by laser ablation using the laser lift-off method. As a result, it becomes possible to repeatedly mount light-emitting diodes in the same location, which was not possible with conventional organic compositions as the adhesive layer.

[0134] The adhesive principle of silicone-based pressure-sensitive adhesives lies in the fact that tack force is generated by the material's inherent adhesive strength and the external force acting as pressure. Since tack force is sufficiently generated by a displacement of a few microns to about 5 μm, a thickness of about 5 to 10 μm is sufficient. Of course, there is no problem even if it is thicker than that.

[0135] [Laser light] Next, we will explain in more detail the type of laser light that can be used in the laser lift-off method.

[0136] When using the laser lift-off method in the selective removal step, the second mounting step, or both, it is preferable to use an excimer laser.

[0137] This method allows for the generation of time-compressed pulsed laser light. The pulse width and light intensity can be easily controlled by controlling device power supply parameters such as the pulse generation voltage, enabling the generation of high-intensity laser light with a single pulse, which is not possible with other continuous-wave (CW) lasers.

[0138] When using the laser lift-off method in the selective removal process, the second mounting process, or both, it is preferable to use a pulsed laser and perform lift-off with a single pulse of laser light irradiation. The reason for this is explained below.

[0139] In the laser lift-off method, using a CW laser results in low energy per wavelength, making it difficult to remove the light-emitting diode (LED) by laser ablation without prolonged laser irradiation. Thus, even if removal is possible with a CW laser, the laser energy at the moment of removal is low, making it difficult to propel the LED from the supply substrate to the receiving substrate. In contrast, pulsed lasers can extract high-energy pulsed laser light with compressed time, allowing for instantaneous laser ablation with a single pulse. As a result, the force propelling the LED from the supply substrate to the receiving substrate is strong and instantaneous, making it suitable for LED transfer using the laser lift-off method.

[0140] In particular, it is preferable to use an excimer laser among pulsed lasers. Practically preferred types of excimer lasers include XeCl (308nm), KrF (248nm), and ArF (193nm). For example, the LAMBDA SX from COHERENT is a XeCl excimer laser that outputs a maximum pulse energy of 1000mJ and is available in systems with maximum pulse repetition frequencies of 500Hz (500W) and 600Hz (600W).

[0141] Examples of KrF and ArF excimer lasers include the IndyStar series from Coherent. The KrF laser has a maximum output of 12W and can oscillate at a maximum pulse repetition frequency of 1kHz with a maximum pulse energy of 12mJ. Furthermore, it can oscillate at a maximum pulse repetition frequency of 2kHz with a maximum pulse energy of 6mJ.

[0142] In the case of ArF, it has a maximum output of 8W and can oscillate at a maximum pulse repetition frequency of 1kHz with a maximum pulse energy of 8mJ. Furthermore, it can oscillate at a maximum pulse repetition frequency of 2kHz with a maximum pulse energy of 4mJ.

[0143] When the pulse repetition frequency is 1 kHz, the pulse time interval is 1 msec. In reality, the time for the placement process is added, so the manufacturing method of the light-emitting diode supply substrate of the present invention is rate-limited by the stage movement time, but it is possible to transfer at an extremely high speed compared to the stamping method. Furthermore, in the selective removal step and the second mounting step of the manufacturing method of the light-emitting diode supply substrate of the present invention, the main objectives are not to transfer all light-emitting diodes placed on the entire surface of the substrate at once, but rather to remove defective light-emitting diodes and mount normal light-emitting diodes in their place, respectively. Therefore, it is an extremely useful method for manufacturing a supply substrate that does not contain defective light-emitting diodes.

[0144] Furthermore, although the energy of the excimer laser light itself is high, the pulse length of each pulse is very short (24 nsec (FWHM) for XeCl, and 7 nsec (FWHM) for KrF and ArF), which has the advantage of leaving less damage to the laser-irradiated area.

[0145] Furthermore, if there are pulsed lasers other than excimer lasers that have sufficient performance to realize the present invention, those may also be used.

[0146] Thus, the laser used in the selective removal process, the second loading process, or both is not limited to an excimer laser; any laser capable of generating pulsed laser light of the required intensity can be used.

[0147] When the process of transferring multiple light-emitting diodes simultaneously in the first mounting process is performed using the laser lift-off method, the laser used is not particularly limited and may be a CW laser.

[0148] [Light-emitting diode] Next, the light-emitting diode used in the manufacturing method of the light-emitting diode supply substrate of the present invention will be described in more detail.

[0149] Generally, light-emitting diodes (LEDs) with a short side of 100 μm or more to 300 μm are called mini LEDs, while those with a short side of 100 μm or less, and even 50 μm or less, are called micro LEDs. Recently, some companies have prioritized commercial advantages and are calling 150 μm x 150 μm LEDs micro LEDs. While it is difficult to precisely define these scales, the LEDs to which this invention relates are those referred to as mini LEDs or micro LEDs.

[0150] For example, in the case of a miniature light-emitting diode (LED) with dimensions of 100 μm x 200 μm, the height was previously less than 100 μm. However, recently, thin-film blue and green LEDs with dimensions of 150 μm x 150 μm x slightly less than 10 μm have begun to appear. Correspondingly, red LEDs with a height nearly twice that size are now available. In the case of microature LEDs with a planar size of less than 100 μm x 100 μm, further thinning has progressed, with the electrode and other components being less than 10 microns in size, and some even around 7 microns. In terms of planar LED size, LEDs with dimensions of 25 μm x 25 μm x 7 μm are already being produced.

[0151] When transferring mini and micro light-emitting diodes (LEDs) as described above using the laser lift-off method, it is preferable to adjust the distance between the LED supply substrate and the receiving substrate so that the flight distance is approximately four times the length of one side of the planar size or less. Preferably, it should be adjusted to approximately three times the length of one side of the planar size or less, and even more preferably to twice the length of one side of the planar size or less. With a flight distance of approximately four times the length of one side of the planar size, it is possible to transfer LEDs using the laser lift-off method by adjusting the laser light intensity, its in-plane uniformity, and the laser light irradiation size. The laser irradiation size should be approximately the same as or slightly larger than the size of the target LED.

[0152] Of course, the gap can be approximately the same as or less than the length of one side of the planar size. While this is difficult to achieve with ordinary quartz substrates, by using a synthetic quartz substrate with in-plane film thickness uniformity of 1 μm or less (TTV) as the base material for the supply substrate, it is possible to reduce the gap between the supply substrate and the receiving substrate to several tens of microns. The limit of this gap distance depends on the potential of the equipment that handles the supply substrate and the receiving substrate.

[0153] In a light-emitting diode supply substrate, multiple light-emitting diodes can be arranged such that one or more red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes form a set of pixels.

[0154] For example, in the second mounting process, supply substrates for red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes can be manufactured, and these supply substrates can be used to transfer red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes onto further supply substrates such that one or more of each form a set of pixels.

[0155] This approach allows for the transfer of LEDs in batches or pixel by pixel during the manufacturing process of light-emitting diode displays.

[0156] Next, with reference to the drawings, several embodiments of the method for manufacturing a light-emitting diode supply substrate of the present invention will be specifically described.

[0157] (First Embodiment) Figures 1 and 2 illustrate a first embodiment of the method for manufacturing a light-emitting diode supply substrate according to the present invention.

[0158] In Figure 1, 1 is a first sapphire substrate as a starting substrate, and 2 is a light-emitting diode (LED) which is in a fragmented state after being manufactured on the starting substrate (first sapphire substrate) 1. 3 shows the electrodes provided on the light-emitting diode 2. 4 is a first supply substrate, which includes a substrate 41 made of a quartz substrate and an adhesive layer 42 formed on one of its surfaces. 6 is laser light. 7 is a container for collecting defective light-emitting diodes 2'. 8 is a second sapphire substrate as a replenishment substrate. The replenishment substrate (second sapphire substrate) 8 is fragmented and contains a light-emitting diode 9 with electrodes 3 formed on it, similar to the starting substrate 1 in Figure 1(a). In Figure 2, 5 is a second supply substrate, which includes a substrate 51 made of a quartz substrate and an adhesive layer 52 formed on one of its surfaces.

[0159] A method for manufacturing a light-emitting diode supply substrate according to the first embodiment of the present invention will be described with reference to Figures 1(a) to (e) and Figures 2(f) and (g).

[0160] (1st loading process) First, using Figure 1(a), we will explain an example of the first mounting process in which multiple light-emitting diodes are mounted on a supply substrate.

[0161] As shown in Figure 1(a), the surface of the first supply substrate 4 on which the adhesive layer 42 is provided (front surface) and the surface of the starting substrate 1 on which the light-emitting diode 2 is manufactured (front surface) are arranged parallel to each other and adjusted so that there is a constant distance between them in plane. In this state, laser light 6 is incident on the back surface of the starting substrate 1 (the surface on which the light-emitting diode 2 is not placed), and this laser light 6 is focused near the interface between the desired light-emitting diode 2 and the starting substrate 1. If the light-emitting diode 2 is a blue or green light-emitting diode, a GaN layer of the light-emitting diode 2 exists at the interface between the starting substrate 1 and the light-emitting diode 2 manufactured on the starting substrate 1. When the laser light 6 reaches this layer, a part of the GaN layer evaporates due to laser ablation, and the light-emitting diode 2 is separated from the starting substrate 1. This method is a form of the laser lift-off method. The separated light-emitting diode 2 then flies toward the adhesive layer 42 of the opposing first supply substrate 4, adheres to the adhesive layer 42, and is fixed in place. As shown in Figure 1(a), the laser beam 6 is moved along the back surface of the starting substrate 1, transferring all the light-emitting diodes 2 from the starting substrate 1 to the surface of the adhesive layer 42 of the first supply substrate 4 all at once. Figure 1(b) shows the state after all the desired light-emitting diodes 2 have been transferred in this manner.

[0162] In Figure 1(a), when using a CW laser to perform the laser lift-off method in the first mounting process for transferring multiple light-emitting diodes at once, it is preferable to press the electrode portion 3 of the light-emitting diode 2 against the adhesive layer 42 (not shown). This makes it possible to transfer multiple light-emitting diodes at once using laser lift-off even with a CW laser.

[0163] (Selection and removal process) Next, an example of a process for selectively removing defective light-emitting diodes will be explained using Figure 1(c).

[0164] First, defective light-emitting diodes 2' to be removed are selected from among the light-emitting diodes 2 on the first supply substrate 4. This selection can be made, for example, based on the results of the determination process described earlier.

[0165] Next, a laser beam 6 is irradiated from the back side of the first supply substrate 4 (the side on which the light-emitting diodes 2 are not placed), and the laser beam 6 is directed at the defective light-emitting diodes 2' adhering to the adhesive layer 42 on the surface of the first supply substrate 4, selectively removing the defective light-emitting diodes 2' by the laser lift-off method. More specifically, in this case, the laser beam 6 is focused and irradiated near the electrode 3 of the defective light-emitting diode 2' and the portion of the adhesive layer 42 that is in contact with the defective light-emitting diode 2', causing a difference in thermal expansion coefficient between the defective light-emitting diode 2' and electrode 3 and the adhesive layer 42, resulting in shear stress at their interface. As a result, the defective light-emitting diode 2' and the electrode 3 formed on it are instantaneously peeled off and removed. The peeled-off light-emitting diodes 2' are captured by a container 7 for collecting defective light-emitting diodes. This is also a form of the laser lift-off method. In this way, by selectively performing the peeling and removal operation while moving the irradiation position of the laser beam 6 over the defective light-emitting diodes 2' to be selectively removed, all defective light-emitting diodes 2' on the first supply substrate 4 are removed.

[0166] Furthermore, the position 10 of the defective light-emitting diode 2' can be determined in advance on the starting substrate 1 during the judgment process described earlier, by mapping and recording its position information.

[0167] (2nd loading process) Next, using Figure 1(d), we will explain an example of a second mounting process in which a normal light-emitting diode is transferred to the location where a defective light-emitting diode was placed on the supply substrate.

[0168] As shown in Figure 1(d), the first supply substrate 4 is positioned with its surface (adhesive layer 42) facing upwards (opposite to gravity), and the replenishment substrate (second sapphire substrate) 8 is positioned on top of it with its surface facing downwards, parallel to each other at a certain distance. Simultaneously, with the rotation of the X-Y axes of the surface of the first supply substrate 4 and the XY axes of the surface of the replenishment substrate 8 corrected, the substrates are aligned and positioned so that the position of the normal light-emitting diode 9 on the replenishment substrate 8 to be replaced coincides with the position 10 where the defective light-emitting diode 2' was located on the first supply substrate 4 (the position where the normal light-emitting diode 9 is to be replaced). Furthermore, in the Z-axis direction, the distance between the surface of the replenishment substrate 8 and the surface of the first supply substrate 4 is adjusted to the optimal distance. In other words, the manufacturing method of the light-emitting diode supply substrate of the first embodiment further includes a positioning step between the selective removal step and the second mounting step in which the replenishment substrate 8 is positioned opposite the first supply substrate 4, and in this positioning step, the positions 10 on the first supply substrate 1 where the defective light-emitting diode 2' was located and the positions of the normal light-emitting diode 9 on the replenishment substrate 8 are aligned opposite each other.

[0169] Specifically, although not shown in the figures, this can be realized by a three-dimensional position alignment system in which at least one or both of the stage that holds the replenishment substrate 8 and the stage that holds the first supply substrate 4 have an XY movement mechanism, at least one of the stages has a mechanism that can correct rotation, and at least one of the stages has a Z-direction movement mechanism.

[0170] Next, after the above placement process is completed, laser light 6 is shone from the back surface of the replenishment substrate 8 towards the normal light-emitting diode 9, and the light-emitting diode is transferred to the defective portion of the first supply substrate 4 (the position where the defective light-emitting diode 2' was located) 10 by the laser lift-off method. This is also a form of the laser lift-off method (second mounting process).

[0171] By repeatedly performing the above arrangement step and the second mounting step, a first light-emitting diode supply substrate 100 that does not contain any defective light-emitting diodes 2' can be manufactured, as shown in Figure 1(e).

[0172] The position of a normal light-emitting diode 9 can be determined in advance on the replacement substrate 8 by performing a normal / failure determination and mapping and recording that position information.

[0173] (Reversal process) In the state shown in Figure 1(e), the electrode 3 side of the light-emitting diode 2 on the first light-emitting diode supply substrate 100 is facing the adhesive layer 5 side, so it cannot be used as is for transfer to the light-emitting diode display panel. Therefore, it is necessary to further invert all the light-emitting diodes 2. The inversion process performed here is described below.

[0174] First, a second supply substrate 5 is prepared as shown in Figure 2(f). Next, as shown in Figure 2(f), the adhesive layer 42 side (surface) of the first supply substrate 4 on which the light-emitting diodes 2 are mounted is placed on the surface (front) of the second supply substrate 5 with the adhesive layer 52, with the adhesive layer 42 side (front) facing downwards, so that they are parallel to each other at a certain distance apart. In this state, the laser lift-off method is performed to cause laser ablation, and all the light-emitting diodes 2 on the first supply substrate 4 are flipped over and transferred to the second supply substrate 5. As a result, a second light-emitting diode supply substrate 200 can be manufactured as shown in Figure 2(g).

[0175] Thus, according to the first embodiment of the present invention, first and second light-emitting diode supply substrates 100 and 200 that do not contain defective light-emitting diodes 2' can be manufactured.

[0176] Next, an example of a method for manufacturing a light-emitting diode display using the second light-emitting diode supply substrate manufactured as described above will be briefly explained with reference to Figure 3.

[0177] In the example shown in Figure 3, as shown in Figure 3(h), the light-emitting diode supply substrate 200 and the display panel substrate 39 to which the diodes are supplied are arranged facing each other so that the positions of the light-emitting diodes 2 on the light-emitting diode supply substrate 200 and the electrode positions on the display panel substrate 39 are aligned.

[0178] In this state, as shown in Figure 3(h), the multiple light-emitting diodes 2 are transferred and placed collectively from the second light-emitting diode supply substrate 200 to the display panel substrate 39 using the laser lift-off method, following the same procedure as described with reference to Figure 9(IV). By then making electrical connections, a light-emitting diode display (or a light-emitting diode display panel as a divided unit thereof) 300 can be obtained, which comprises the display panel substrate 39 and the multiple light-emitting diodes 2 arranged on this substrate, as shown in Figure 3(i).

[0179] Although not shown in the figures, multiple light-emitting diodes 2 can also be transferred and placed simultaneously from the second light-emitting diode supply substrate 200 to the display panel substrate 39 using the stamping method.

[0180] According to the manufacturing method examples described above, assembly work that does not include defective light-emitting diodes can be achieved. This process can be performed for each RGB color to manufacture an RGB color light-emitting diode display (light-emitting diode display panel).

[0181] Thus, by manufacturing using a light-emitting diode supply substrate that can be manufactured by the first embodiment of the method for manufacturing a light-emitting diode supply substrate of the present invention, it becomes possible to manufacture a light-emitting diode display with extremely few light-emitting defects.

[0182] If the process of transferring the light-emitting diodes 2 from the second light-emitting diode supply substrate 200 to the display panel substrate 39 is performed by laser ablation using the laser lift-off method, the transfer can be performed non-contact and at high speed, enabling the practical and highly efficient manufacture of a light-emitting diode display 300. Thus, the light-emitting diode supply substrate 200 manufactured by the manufacturing method of the light-emitting diode supply substrate of the present invention is extremely useful for realizing inorganic light-emitting diode displays, so-called mini light-emitting diode displays, or micro light-emitting diode displays.

[0183] Furthermore, during the manufacturing of the second light-emitting diode supply substrate 200, it is preferable to lay out red, green, and blue light-emitting diodes at least one of each color at the pixel pitch required for the display, thereby forming a group of RGB light-emitting diodes for one pixel. To achieve this, the first supply substrate 100 for each RGB color light-emitting diode 2 is used to control the transfer position to the second supply substrate 5 for each color, thereby arranging the RGB light-emitting diodes at the display pitch and corresponding to the electrode positions on the display panel substrate 39. In this way, if the second light-emitting diode supply substrate 200 is manufactured with a pixel configuration and pixel pitch that corresponds to the desired display panel substrate 39, the RGB display 300 can be assembled simply by transferring multiple light-emitting diodes from the second light-emitting diode supply substrate 200 to the display panel substrate 39 all at once.

[0184] Furthermore, it is preferable that the light-emitting diodes 2 are arranged such that the pitch of the arrangement matrix (XY) for each RGB color is equal to the pixel pitch of the display panel, or 1 / N of the pixel pitch P.

[0185] To achieve this, the light-emitting diodes 2 can be transferred to the desired pixel pitch P or P / N pitch position in the process of transferring the light-emitting diodes from the first supply substrate 4 to the second supply substrate 5, or in the process of transferring them from the starting substrate 1 to the first supply substrate 4 (first mounting process). Furthermore, when transferring and arranging the light-emitting diodes 2 on the first supply substrate 4 and / or the second supply substrate 5, by arranging them at a pitch (P / N) that is 1 / N of the desired pixel pitch P, and at a pitch where each light-emitting diode 2 does not overlap, a second light-emitting diode supply substrate 200 with a maximum mounting capacity corresponding to the desired pixel pitch can be manufactured.

[0186] By using a second light-emitting diode supply substrate 200 equipped with light-emitting diodes 2 at P / N (N: integer) pitch positions, the transfer speed when mounting the light-emitting diodes 2 to the display panel substrate 39 can be significantly improved. Specifically, when transferring light-emitting diodes from the second light-emitting diode supply substrate 200 to the display panel substrate 39 using the laser lift-off method, the laser irradiation position can be optically moved to selectively transfer the light-emitting diodes 2 at desired pixel pitch positions on the XY matrix, allowing multiple light-emitting diodes 2 to be transferred all at once (in a single step) in a placement process that includes a single stage movement.

[0187] Next, the chip position adjacent to the position of the light-emitting diode 2 transferred by the laser lift-off method is moved to the next transfer position (pitch position of the display panel), and the transfer is performed using the selective laser lift-off method. By repeating this series of operations, a light-emitting diode display panel with light-emitting diodes 2 at the pixel pitch position can be manufactured at approximately N times the speed. By sequentially performing the above series of operations for each color of light-emitting diode, an RGB light-emitting diode display 300 or a divided display unit (e.g., a light-emitting diode display panel) 300 can be manufactured.

[0188] As described above, if a light-emitting diode supply substrate is manufactured with the light-emitting diodes positioned in a location suitable for mounting and assembling the light-emitting diodes to the display during the manufacturing stage, the manufacturing efficiency can be further improved in the manufacturing and assembly process of the display or the divided unit of the display.

[0189] Furthermore, when transferring the light-emitting diodes 2 in a batch from the starting substrate 1 to the first supply substrate 4 using the laser lift-off method as shown in Figure 1(a), and when transferring the light-emitting diodes 2 in a batch from the first supply substrate 4 to the second supply substrate 5 as shown in Figure 2(f), operations that do not involve stage movement are preferable from a practical time standpoint to operations that involve stage movement, such as the removal of defective light-emitting diodes 2' (Figure 1(c)) and the second mounting process of normal light-emitting diodes 9 (Figure 1(d)). In such cases, batch transfer can be achieved in a practical time by scanning the laser beam 6. In this case, the high repetition frequency of the excimer laser is effective. Also, because a high-power laser beam can be obtained, the laser beam spot size can be expanded to cover an area that covers multiple light-emitting diodes 2, rather than transferring each individual light-emitting diode 2 with a divided irradiation area, and multiple diodes can be transferred together. The spot shape may be square or rectangular. By synchronizing the laser light irradiation with the pulse oscillation frequency or an integer multiple thereof, and blocking unwanted pulsed light with an optical shutter, the light-emitting diode can be efficiently transferred.

[0190] (Second Embodiment) Figures 4 and 5 illustrate a method for manufacturing a light-emitting diode supply substrate according to a second embodiment of the present invention.

[0191] The first embodiment described above is characterized by performing the steps from selectively removing defective light-emitting diodes 2' to transferring normal light-emitting diodes 9 on the first supply substrate 4, as shown in Figures 1(c) and (d). On the other hand, the second embodiment shown in Figures 4 and 5 is characterized by performing the steps from selectively removing defective light-emitting diodes 2' to transferring normal light-emitting diodes 9 on the second supply substrate 5, as shown in Figures 5(e2) and (f2). Furthermore, a difference is that the substrate used to supply the normal light-emitting diodes 9 is a third supply substrate 11 as a replenishment substrate. As the third supply substrate 11, for example, one manufactured in the same way as the first supply substrate 4 obtained in Figure 4(b2) can be used. Naturally, the results of the normal / abnormal determination of the light-emitting diodes 2 and 9 on the starting substrate 1, along with their position information, are carried over when the light-emitting diodes 2 and 9 are transferred together from the starting substrate 1 to the first supply substrate 4 and the third supply substrate 11.

[0192] Furthermore, if the first light-emitting diode supply substrate 100 in the state shown in Figure 1(e) of the first embodiment, that is, the state in which the light-emitting diodes 2' that were determined to be defective have been removed and all normal light-emitting diodes 2 have been mounted, is used as the third supply substrate 11 shown in Figure 5(f2) of the second embodiment of the present invention, all light-emitting diodes 2 of the first light-emitting diode supply substrate 100 can be used without distinction. As a result, the efficiency of the placement process and the second mounting process on the second supply substrate 5 shown in Figure 5(f2) can be improved.

[0193] (Third embodiment) Figure 6 shows a portion of an explanatory diagram for the manufacturing method of a light-emitting diode supply substrate according to the third embodiment of the present invention, highlighting the differences from the second embodiment of the present invention.

[0194] Figure 6(f') is characterized by using a replenishment substrate (second sapphire substrate) 8 instead of the third supply substrate 11 in the process shown in Figure 5(f2) of the second embodiment of the present invention. The illustrated replenishment substrate 8 is the same as the one shown in Figure 1(d) of the first embodiment of the present invention.

[0195] The second light-emitting diode supply substrate 200, shown in Figure 6(g'), obtained by the process shown in Figure 6(f'), is the same as those shown in Figures 2(g) and 5(g2).

[0196] (Fourth Embodiment) In the first to third embodiments described above, the first mounting step involves transferring multiple light-emitting diodes 2 from the manufacturing source substrate 1 to the first supply substrate 4, as shown in Figures 1(a) and 4(a2). This can be achieved when the light-emitting diodes 2 are blue and green light-emitting diodes because the interface between the source substrate (sapphire substrate) 8 and the light-emitting diodes 2 is a GaN layer. More specifically, the GaN layer at the interface is ablated and the nitrogen sublimes, causing the light-emitting diodes 2 to peel off from the source substrate 8 and be ejected. Furthermore, this is possible in blue and green light-emitting diodes because they have a lateral structure in which the electrodes are formed on the same side.

[0197] However, in the case of red LEDs, the starting substrate itself is formed on a GaAs substrate, and the electrodes are usually formed so as to sandwich the light-emitting diode, a so-called vertical structure was the mainstream. When this was used as is in a display panel, there was a problem in that the electrode connection became even more complicated because it was a different structure from the lateral structure of blue and green light-emitting diodes. To overcome this problem, lateral structure red light-emitting diodes have been manufactured and are now available on the market.

[0198] Figure 7 is a part of an explanatory diagram for the method of manufacturing a light-emitting diode supply substrate according to the fourth embodiment of the present invention.

[0199] In Figure 7, 21 is the starting substrate (sapphire substrate), and 22 is the red light-emitting diode (LED). 23 and 24 are electrodes provided on the LED, and electrodes 23 and 24 are connected to the conductive layer on the opposite side of the red LED 22, respectively. Thus, the electrodes of the red LED 22 are configured in a lateral structure. The red LED 22 is fixed to the starting substrate 21 by an adhesive layer 25. The adhesive layer 25 is generally made of a resin such as BCB (Benzocyclobutene). Also, 4 is the first supply substrate, which includes a substrate 41 and an adhesive layer 42 formed thereon.

[0200] In the fourth embodiment, as shown in Figure 7(a4), the starting substrate 21 and the first supply substrate 4 are arranged parallel to each other and adjusted so that they are at a constant distance from each other in plane. In this state, a portion of the adhesive layer 25 is ablated by the laser lift-off method to transfer the red light-emitting diode 22, which is fixed to the starting substrate 21 by the adhesive layer 25, to the first supply substrate 4.

[0201] In this case, since BCB residue from the adhesive layer 25 remains on the red light-emitting diode 22, a step is required to remove the BCB residue by chemical etching using a wet process or a dry process, although this step is not shown.

[0202] In this way, the first supply substrate 4 (Figure 7(b2)) is completed. After this, for example, a second supply substrate 5 that does not contain defective light-emitting diodes can be manufactured using the method shown in the first or second embodiment of the present invention.

[0203] The normal / defective determination of the red light-emitting diode 22 can be performed by photoluminescence while the red light-emitting diode 22 is fixed to the starting substrate 1.

[0204] As described above, it is possible to manufacture supply substrates for light-emitting diodes for the manufacture of light-emitting diode displays for each of the following colors: blue, green, and red.

[0205] (Fifth embodiment) In the first to fourth embodiments, during the first mounting process, a laser beam 6 is scanned using the laser lift-off method, maintaining a certain gap between the starting substrate 1 and the first supply substrate 4, to mount each color of light-emitting diode 2 or 22 onto the first supply substrate 4 all at once. Similarly, a certain gap is maintained between the two substrates during the simultaneous transfer from the first supply substrate 4 to the second supply substrate 5. The advantage of this method is that the same adhesive material can be used for the adhesive layers on both the first supply substrate 4 and the second supply substrate 5.

[0206] However, it is possible to perform a batch transfer without necessarily leaving gaps between the transfers.

[0207] Figure 8 is a part of an explanatory diagram for the method of manufacturing a light-emitting diode supply substrate according to the fifth embodiment of the present invention. 5-1 ) corresponds to Figure 1(a), and Figure 8(a 5-2 ) corresponds to Figure 7(a4), and Figure 8(f5) corresponds to Figure 2(f).

[0208] Figure 8(a 5-1 ), Figure 8(a 5-2 As shown in Figure 8(f5), when transferring the light-emitting diode 2 or 22 by the laser lift-off method without leaving a gap, it is preferable in both cases to apply slight pressure to obtain the tacking effect of the adhesive layers 42 and 52.

[0209] Figure 8(a 5-1 ) and Figure 8(a 5-2 In this case, the light-emitting diodes 2 and 22 are peeled off from the starting substrate (sapphire substrate) 1 and the adhesive layer 25, respectively, so the pressing works effectively as described above.

[0210] In the case of Figure 8(f5), by using a material in which the adhesive force (including tack force) of adhesive layer 52 is greater than that of adhesive layer 42, a single transfer by the laser lift-off method is achieved.

[0211] Furthermore, the other steps in the fifth embodiment may be, for example, the other steps in the first or second embodiment.

[0212] By using the second light-emitting diode supply substrate 200 manufactured by the manufacturing method of the light-emitting diode supply substrate according to the second to fourth embodiments, a light-emitting diode display (or a divided unit of a light-emitting diode display or a light-emitting diode display panel) 300 can be manufactured, for example, by the procedure shown in Figure 3, similar to the case when using the second light-emitting diode supply substrate 200 manufactured by the manufacturing method of the light-emitting diode supply substrate according to the first embodiment.

[0213] [Manufacturing method for light-emitting diode displays and manufacturing method for divided units of light-emitting diode displays] The present invention's method for manufacturing a light-emitting diode display is: The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a display panel substrate. It is characterized by having the following features.

[0214] Furthermore, the method for manufacturing the divided unit of the light-emitting diode display of the present invention is as follows: The present invention provides a method for manufacturing a light-emitting diode supply substrate, comprising the steps of manufacturing the light-emitting diode supply substrate and A step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto a divided unit of a light-emitting diode display. It is characterized by having the following features.

[0215] In the method for manufacturing a light-emitting diode display and a divided unit of a light-emitting diode display of the present invention, a light-emitting diode supply substrate is manufactured using the method for manufacturing a light-emitting diode supply substrate of the present invention, and a plurality of light-emitting diodes are transferred using this substrate to a light-emitting diode display substrate or a divided unit of a light-emitting diode display. This allows for the efficient manufacture of a light-emitting diode display or a divided unit of a light-emitting diode display that does not contain defective light-emitting diodes. In other words, the method for manufacturing a light-emitting diode display of the present invention enables the manufacture of a light-emitting diode display with a high yield. Furthermore, the method for manufacturing a divided unit of a light-emitting diode display of the present invention enables the manufacture of a divided unit of a light-emitting diode display with a high yield.

[0216] It is preferable to perform the step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto the display panel substrate by a laser lift-off method. This method allows for faster transfer of multiple light-emitting diodes, thus providing a more practical method for manufacturing light-emitting diode displays.

[0217] Similarly, it is preferable to perform the step of transferring the plurality of light-emitting diodes on the light-emitting diode supply substrate onto the divided unit of the light-emitting diode display by the laser lift-off method. This method allows for faster transfer of multiple light-emitting diodes, thus providing a more practical method for manufacturing segmented units of light-emitting diode displays.

[0218] Specific examples of the method for manufacturing a light-emitting diode display and the method for manufacturing a divided unit of the light-emitting diode display of the present invention are described with reference to Figures 1 to 3.

[0219] Furthermore, according to the manufacturing method of the light-emitting diode display and the manufacturing method of the segmented unit of the light-emitting diode display of the present invention, for example, a high-resolution large-screen display and its segmented unit can be manufactured. However, according to the manufacturing method of the light-emitting diode display and the manufacturing method of the segmented unit of the light-emitting diode display of the present invention, by using a light-emitting diode supply substrate manufactured by the manufacturing method of the light-emitting diode supply substrate of the present invention, display function units for wristwatch-sized healthcare devices, composite devices, in-vehicle head-up displays and navigation system displays, AR / VR / MR and other visual enhancement devices, glasses-type display devices, etc., can be provided. As a result, electrical and electronic equipment equipped with the above-mentioned light-emitting diode display or its segmented unit can be manufactured and provided with a high yield.

[0220] [Manufacturing method for element supply substrate] The present invention relates to a method for manufacturing an element supply substrate, which is a method for manufacturing an element supply substrate for transferring a plurality of elements to a supply destination, A first mounting process involves mounting multiple elements onto a supply substrate, A selective removal step for selectively removing defective elements on the supply substrate, A second mounting step involves transferring a normal element to the position on the supply board where the defective element was located. It is characterized by including.

[0221] In the method for manufacturing a light-emitting diode supply substrate of the present invention, by applying elements such as micro-electrical elements or micro-semiconductor chips instead of light-emitting diodes, it is possible to manufacture an element supply substrate that can be used for 3D mounting and the manufacture of electrical and electronic equipment.

[0222] By using the element supply substrate manufactured in this manner, multiple normal elements can be transferred to the supply destination in a single operation using either the laser lift-off method or the stamping method. In other words, the method for manufacturing an element supply substrate according to the present invention makes it possible to manufacture an element supply substrate that can transfer multiple normal elements to the supply destination in a single operation. Furthermore, elements at a desired position on the element supply substrate manufactured according to the present invention can be selected and transferred to the supply destination using the laser lift-off method. In other words, it is possible to manufacture an element supply substrate that can transfer normal elements regardless of the selected position.

[0223] Furthermore, this method for manufacturing element supply substrates can be used, for example, in 3D packaging and the manufacturing of electrical and electronic equipment.

[0224] Miniature electrical elements include resistors, capacitors, and inductors. Miniature semiconductor chips include Si-CMOS semiconductor ICs and LSIs, discrete semiconductors such as diodes, and compound semiconductor chips. We can also handle MEMS elements such as acceleration sensors.

[0225] It should be noted that the present invention is not limited to the embodiments described above. The embodiments described above are illustrative, and any configuration that is substantially identical to the technical idea described in the claims of the present invention and achieves similar effects is included within the technical scope of the present invention. [Explanation of Symbols]

[0226] 1, 21... Starting substrate, 2... Light-emitting diode (blue light-emitting diode, green light-emitting diode), 2'... Faulty light-emitting diode, 3, 23, 24... Electrode, 4... First supply substrate, 5... Second supply substrate, 6... Laser light, 7... Container, 8... Replacement substrate, 9... Normal light-emitting diode, 10... Location where the faulty light-emitting diode was placed, 11... Third supply substrate, 22... Red light-emitting diode, 25... Adhesive layer, 42, 52... Adhesive layer, 39... Destination (light-emitting diode display substrate), 41, 51... Substrate, 100... First light-emitting diode supply substrate, 200... Second light-emitting diode supply substrate, 300... Light-emitting diode display (light-emitting diode display panel).

Claims

1. A method for manufacturing an element supply substrate for transferring multiple elements to a supply destination, A first mounting step involves mounting multiple elements on the adhesive layer of a supply substrate having an adhesive layer on one side, A selective removal step in which defective elements are selectively removed from among a plurality of elements on the supply substrate by irradiation with laser light, A second mounting step involves removing the defective element and re-adhering a normal element to the exposed adhesive layer. A method for manufacturing an element supply substrate, wherein the laser light is irradiated onto the defective element from the back side of the supply substrate opposite to the one side of the supply substrate.

2. The method for manufacturing an element supply substrate according to claim 1, wherein the element is a light-emitting diode, an electrical element, a semiconductor chip, or a MEMS element.

3. The method for manufacturing an element supply substrate according to claim 1 or 2, wherein the adhesive layer does not undergo ablation at the interface between the adhesive layer and the defective element due to irradiation with the laser light in the selective removal step.

4. The method for manufacturing an element supply substrate according to any one of claims 1 to 3, wherein the adhesive layer is formed from a pressure-sensitive adhesive mainly composed of silicone.

5. The method for manufacturing an element supply substrate according to any one of claims 1 to 3, wherein the adhesive layer is formed from a composition comprising PDMS, a silicone composition in which the side chains and both ends of PDMS have been modified, or a combination thereof.

6. A method for manufacturing an electrical device in which elements are supplied from an element supply board manufactured by the method for manufacturing an element supply board according to any one of claims 1 to 5.

7. A method for manufacturing an electrical device according to claim 6, comprising the step of inverting the element.

8. A method for manufacturing an electronic device in which elements are supplied from an element supply board manufactured by the method for manufacturing an element supply board according to any one of claims 1 to 5.

9. A method for manufacturing an electronic device according to claim 8, further comprising the step of inverting the element.

10. A three-dimensional mounting method in which elements are supplied from an element supply substrate manufactured by the method for manufacturing an element supply substrate according to any one of claims 1 to 5.

11. The three-dimensional mounting method according to claim 10, further comprising the step of inverting the element.

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