Method for manufacturing element supply substrate, method for manufacturing electric apparatus, method for manufacturing electrical apparatus and three-dimensional 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 board, a method for manufacturing a light-emitting diode display, a method for manufacturing a division unit of a light-emitting diode display, and a method for manufacturing an element supply board. [Background technology]

[0002] In recent years, the development of displays using miniature light-emitting diodes and micro light-emitting diodes has been vigorously pursued. One of the major manufacturing challenges for their practical application is the manufacturing method for arranging the minute light-emitting diodes on the display panel. As an assembly method, a microstructure transfer technology using a stamp has attracted attention (for example, Patent Document 1, Non-Patent Document 1).

[0003] To assemble a full HD (1920 x 1080) display panel using this technology, transferring LEDs one by one from an LED supply board would require transferring 2,073,600 pixels. To manufacture a color display, at least three types of mini or micro LEDs—red (R), green (G), and blue (B)—are required for each pixel. Transferring each element individually would require more than 6 million transfers. For a 4K display, this would require more than 24 million transfers. Even with this laborious display assembly, if a supply board containing a large number of defective LEDs is used, the problem remains: the need to replace good LEDs on the display panel board, i.e., repair the defective LEDs. Therefore, there is a strong demand for a supply board containing only good LEDs. This problem persists even when batch transfer is performed from the supply board to the display panel board.

[0004] Laser lift-off is a faster and more efficient alternative to stamping. 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 by laser irradiation, separating the element from the substrate. This method has the drawback of adhering the release layer material to the microfunctional element, necessitating post-transfer cleaning, making it an ineffective method. A method that does not require a release layer utilizes the pressure-sensitive adhesive properties of the silicone resin PDMS (PolyDiMethylSiloxane) (Patent Document 3, Non-Patent Document 2). This method prevents unwanted materials from adhering to the microfunctional element after laser lift-off, raising expectations for laser lift-off using silicone resin. Patent Document 4 describes an example of an apparatus for transferring microfunctional elements using laser lift-off.

[0005] An example of a conventional method for manufacturing a light-emitting diode display panel using the above-mentioned laser lift-off method will be described below with reference to Fig. 9. Figs. 9(I) to (III) show an example of the process for manufacturing a supply substrate from a light-emitting diode manufacturing substrate, and Figs. 9(IV) and (V) show the process for transferring light-emitting diodes one by one to a display panel substrate using the above-mentioned stamp method.

[0006] In Fig. 9(I), 1 denotes a sapphire substrate as a starting substrate, on one surface of which a plurality of GaN-based light-emitting diodes 2 are formed and processed into an individually separated state. The light-emitting diodes 2 further include electrodes 3. 4 denotes a first supply substrate, which comprises a substrate 41 made of quartz and a silicone resin layer 42 formed thereon as an adhesive layer.

[0007] As shown in FIG. 9(I), the first supply substrate 4 and the starting substrate (sapphire substrate) 1 are positioned so that the LEDs 2 face the adhesive layer 42, maintaining a constant gap between them and an optimal distance apart. In this state, a laser beam 6 is irradiated from the surface of the starting substrate 1 on which the LEDs 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 LEDs 2, resulting in a thin layer of laser ablation of the GaN on the side of the LEDs 2 near this interface. This is the so-called laser lift-off process, in which the LEDs 2 are separated from the starting substrate 1 and ejected toward the first supply substrate 4 facing the LEDs 2. The ejected LEDs 2 then travel to the surface of the adhesive layer (silicone resin layer) 42 and are temporarily bonded to the surface of the adhesive layer 42. By scanning the desired area of ​​the starting substrate 1 with the laser beam 6, all of the desired LEDs 2 on the starting substrate 1 can be transferred to the first supply substrate 4, completing the first supply substrate 4 shown in FIG. 9(II). In this case, GaN components do not adhere to the light-emitting diode 2 as residue due to ablation, so there is no need to clean off the adhesions from the release layer as in the case of a release layer (including an organic polymer).

[0008] Next, as shown in Fig. 9(III), a second supply substrate 5 is prepared, which has a substrate 51 and a silicone resin layer 52 thereon as an adhesive layer. Next, this second supply substrate 5 and the first supply substrate 4 of Fig. 9(II) are arranged so that the light-emitting diodes 2 face the adhesive layer 52, with a constant gap between them and an optimum distance apart.

[0009] In this state, a laser beam 6 is scanned and irradiated onto a desired area of ​​the surface of the first supply board 4 where no light-emitting diodes 2 are arranged, thereby completing a second supply board 5 to which light-emitting diodes 2 with electrodes 3 are temporarily attached in an upside-down state. In this way, the second supply board 5 can be fabricated as a light-emitting diode supply board with the electrodes 3 facing outward.

[0010] Next, a display panel substrate 39 is prepared as a supply destination, as shown in FIG. 9(IV). The display panel substrate 39 includes electrodes and wiring, not shown. This display panel substrate 39 and the second supply substrate 5 are arranged at an optimum distance so that the gap between them is constant. In this state, laser light 6 is irradiated from the surface of the second supply substrate 5 on which the light-emitting diodes 2 are not arranged. By this laser lift-off method, the plurality of light-emitting diodes 2 are transferred from the second supply substrate 5 to the display panel substrate 39, as shown in FIG. 9(V).

[0011] In this way, the electrodes 3 of the light-emitting diodes 2 are arranged so as to be in electrical contact with desired electrode positions on the display panel substrate 39 using the laser lift-off method, thereby completing the display panel 300 (FIG. 9(V)).

[0012] However, even if a display is manufactured using the laser lift-off method, which allows for faster transfer than the stamping method, if a supply substrate containing a large number of defective LEDs is used, there is a problem in that good LEDs must be relocated, i.e., repaired, on the display substrate. Therefore, there is a strong demand for a supply substrate that contains only good LEDs. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Patent No. 7,943,491 [Patent Document 2] Patent No. 5319533 [Patent Document 3] U.S. Patent No. 9,555,644 [Patent Document 4] Japanese Patent Application 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. Summary of the Invention [Problem to be solved by the invention]

[0015] As explained above, whether the stamping method or the laser lift-off method is used, if defective light-emitting diodes are included among the light-emitting diodes mounted on the supply substrate (second supply substrate 5 in Figure 9) that supplies light-emitting diodes to the display panel substrate, the defective light-emitting diodes will be transferred directly to the display panel substrate, which poses a problem of reduced yield of normal transfer.

[0016] The present invention has been made to solve the above problems, and aims to provide a method for manufacturing a light-emitting diode supply board capable of manufacturing a light-emitting diode supply board on which a plurality of normal light-emitting diodes can be transferred to a supply destination, a method for manufacturing a light-emitting diode display with high yield, a method for manufacturing a division unit of a light-emitting diode display with high yield, and a method for manufacturing an element supply board capable of manufacturing an element supply board on which a plurality of normal elements can be transferred to a supply destination. [Means for solving the problem]

[0017] In order to solve the above problems, the present invention provides a method for manufacturing a light emitting diode supply board for transferring a plurality of light emitting diodes to a supply destination, the method comprising the steps of: 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 a normal light-emitting diode to the position on the supply board where the defective light-emitting diode was located; The present invention provides a method for manufacturing a light emitting diode supply substrate, comprising:

[0018] In this way, it is possible to manufacture a light-emitting diode supply board provided with only normal light-emitting diodes. By using the light-emitting diode supply board manufactured in this way, it is possible to transfer a plurality of normal light-emitting diodes to a supply destination all at once or selectively. In other words, according to the manufacturing method of the light-emitting diode supply board of the present invention, it is possible to manufacture a light-emitting diode supply board that can transfer a plurality of normal light-emitting diodes to a supply destination all at once or selectively.

[0019] Furthermore, since the LED supply board manufactured by the method for manufacturing an LED supply board of the present invention does not contain defective LEDs, the occurrence of defective light-emitting defects during the manufacture of LED displays or divided units of LED displays can be significantly reduced, thereby enabling the LED displays or divided units thereof to be manufactured with high yield and high efficiency.

[0020] It is preferable to further include, before the selective removal step, a determination step of determining whether or not each of the light emitting diodes on the supply board is normal.

[0021] In this way, defective light-emitting diodes can be reliably selected and removed.

[0022] The determination step is preferably carried out by a photoluminescence method.

[0023] When the determination step is carried out by a photoluminescence method, the determination can be made without contact.

[0024] The selective removal step, the second mounting step, or both are preferably performed 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, the light-emitting diode supply substrate can be manufactured with higher efficiency.

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

[0027] This allows the generation of time-compressed pulsed laser light. The pulse width and light intensity can be easily controlled by adjusting the device power supply parameters such as the pulse generation voltage, and it is possible to generate high-intensity laser light in a single pulse, which is not possible with other continuous wave (CW) lasers.

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

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

[0030] The light emitting diodes used preferably have a longest length of less than 300 μm.

[0031] In this way, more efficient transfer is possible by the laser lift-off method.

[0032] The light emitting diode may be one selected from the group consisting of a red light emitting diode, a green light emitting diode, and a blue light emitting diode.

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

[0034] The plurality of light emitting diodes may be arranged such that at least one red light emitting diode, at least one green light emitting diode, and at least one blue light emitting diode form a set of pixels.

[0035] In this way, when manufacturing a light-emitting diode display, transfer and mounting can be performed all at once or in units of one pixel.

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

[0037] In this way, the supply substrates for the light-emitting diodes can be manufactured efficiently.

[0038] The second mounting step preparing a supplemental substrate including a quartz substrate, an adhesive layer provided on the quartz substrate, and a plurality of light-emitting diodes adhered in a matrix on the surface of the adhesive layer; Transferring a normal light-emitting diode on the supplemental board to the position on the supply board from which the defective light-emitting diode was removed. It is preferable to carry out the process by the following method.

[0039] In this way, the supply substrate for the light-emitting diode can be manufactured more efficiently.

[0040] It is preferable that the method further includes, between the selective removal step and the second mounting step, a placement step of placing the supplementary substrate so as to face the supply substrate.

[0041] In this way, the accuracy in the second mounting step can be further improved.

[0042] In this case, in the arranging step, it is preferable to align the positions of the defective light-emitting diodes on the supply substrate so that they face the positions of the normal light-emitting diodes on the supplementary substrate.

[0043] This allows a normal light emitting diode to be mounted more accurately in the position where the defective light emitting diode was removed.

[0044] As the supply substrate, it is preferable that the quartz substrate be made of synthetic quartz.

[0045] Synthetic quartz exhibits excellent in-plane film thickness uniformity, and therefore, when synthetic quartz is used for the quartz substrate, it becomes possible to control the gap between opposing substrates for performing the laser lift-off method.

[0046] The quartz substrates of the supplementary substrates are also preferably made of synthetic quartz. In this case, for example, when the supplementary substrates are arranged parallel to and opposite the supply substrate in the arrangement step, they can be arranged at a constant distance with high precision across the entire surface of the substrate.

[0047] The supply substrate may be a quartz substrate provided with a facet.

[0048] In this way, when the supply substrate is set in a transfer device using the laser lift-off method, it can be set in the correct rotational position.

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

[0050] In this case, it is more preferable that the facet is a mark indicating orientation.

[0051] In this case, when the supply substrate is set in the transfer device using the laser lift-off method, it can be set at the correct rotational position.

[0052] The supply substrate may be a quartz substrate having one or more types selected from the group consisting of letters, symbols, and 2D barcodes.

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

[0054] In this way, it becomes possible to manage the supply substrates and replenishment substrates individually.

[0055] The letters, symbols and 2D barcodes may be indicia indicating orientation.

[0056] The letters, symbols, and 2D barcodes can be used to identify the individual supply substrates, and can also be used as marks indicating orientation.

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

[0058] It is preferable that the supply substrate has an adhesive layer made of a pressure-sensitive adhesive containing silicone.

[0059] The supplementary substrate may also be one in which the adhesive layer is made of a pressure-sensitive adhesive containing silicone.

[0060] This provides good adhesive strength. Furthermore, impurities do not adhere to the light-emitting diode when the light-emitting diode is transferred using the laser lift-off method. Furthermore, after the light-emitting diode is removed, the light-emitting diode can be reattached.

[0061] The supply substrate used may have a matrix pitch that is equal to the pixel pitch of the display panel or an integer multiple of the pixel pitch.

[0062] In this way, the supply substrate is moved only to a minimum extent without any unnecessary alignment movement, and the laser irradiation position is moved in a controlled manner, so that a plurality of light emitting diodes can be transferred by the laser lift-off method.

[0063] The first mounting step providing a starting substrate having the plurality of light emitting diodes fabricated thereon; separating the plurality of light-emitting diodes on the starting substrate into individual elements; transferring the plurality of light emitting diodes separated into individual elements onto the supply substrate; It is preferred that the compound contains:

[0064] In this way, the first mounting step can be carried out efficiently.

[0065] The step of transferring the plurality of light emitting diodes onto the supply substrate in the first mounting step is preferably performed by a laser lift-off method.

[0066] In this way, the first mounting step can be carried out more efficiently.

[0067] The present invention also provides a method for manufacturing a light-emitting diode display, comprising the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; 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, comprising the steps of:

[0068] In the method for manufacturing an LED display of the present invention, an LED supply substrate is manufactured by the method for manufacturing an LED supply substrate of the present invention, and then a plurality of LEDs are transferred to an LED display substrate using the LED supply substrate, thereby enabling efficient manufacture of LED displays that do not contain defective LEDs. In other words, the method for manufacturing an LED display of the present invention allows LED displays to be manufactured with a high yield.

[0069] The step of transferring the plurality of light emitting diodes on the light emitting diode supply substrate onto the display panel substrate is preferably performed by a laser lift-off method.

[0070] In this way, a plurality of light emitting diodes can be transferred at higher speed, and therefore a more practical method for manufacturing a light emitting diode display can be provided.

[0071] The present invention also provides a method for manufacturing a division unit of a light-emitting diode display, comprising the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; transferring the plurality of light emitting diodes on the light emitting diode supply board onto a division unit of a light emitting diode display; The present invention provides a method for manufacturing a division unit of a light-emitting diode display, comprising the steps of:

[0072] In the method for manufacturing a divided unit of an LED display of the present invention, an LED supply board is manufactured by the method for manufacturing an LED supply board of the present invention, and then a plurality of LEDs are transferred to the divided unit of an LED display using the LED supply board, so that divided units of an LED display that do not contain defective LEDs can be manufactured efficiently. In other words, the method for manufacturing a divided unit of an LED display of the present invention allows divided units of an LED display to be manufactured with a high yield.

[0073] The step of transferring the plurality of light emitting diodes on the light emitting diode supply substrate onto the division units of the light emitting diode display is preferably performed by a laser lift-off method.

[0074] In this way, a plurality of light emitting diodes can be transferred at higher speed, and therefore a more practical method for manufacturing divided units of a light emitting diode display can be provided.

[0075] Further, the present invention provides a method for manufacturing an element supply substrate for transferring a plurality of elements to a supply destination, the method comprising the steps of: a first mounting step of mounting a plurality of elements on a supply substrate; a selective removal step of selectively removing defective elements on the supply substrate; a second mounting step of transferring a normal element to the position on the supply substrate where the defective element was located; The present invention provides a method for manufacturing an element supply substrate, comprising:

[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 microelectronic elements and microsemiconductor chips. This element supply substrate can transfer multiple normal elements to a destination. The method for manufacturing such an element supply substrate can be used, for example, in three-dimensional packaging and the manufacture of electrical and electronic devices.

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

[0078] In this way, the method for manufacturing an element supply board of the present invention can be applied to supplying various elements. [Effects of the Invention]

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

[0080] Furthermore, since the LED supply board manufactured by the method for manufacturing an LED supply board of the present invention does not contain defective LEDs, the occurrence of defective light-emitting defects during the manufacture of LED displays or LED display division units can be significantly reduced, thereby enabling the LED displays to be manufactured with high yield and high efficiency.

[0081] Furthermore, since the method for manufacturing an LED display and the method for manufacturing a divided unit of an LED display of the present invention include the method for manufacturing an LED supply substrate of the present invention, it is possible to efficiently manufacture an LED display or a divided unit of an LED display that does not contain defective LEDs.

[0082] According to the method for manufacturing an element supply board of the present invention, an element supply board can be manufactured that can transfer a plurality of normal elements to a supply destination all at once or selectively. [Brief explanation of the drawings]

[0083] [Figure 1] 1 is an explanatory view showing a part of a first embodiment of a method for manufacturing a light emitting diode supply board according to the present invention; [Figure 2] FIG. 4 is an explanatory view showing another part of the first embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 3] 3 is an explanatory view showing a part of an example of a method for manufacturing a light-emitting diode display using a light-emitting diode supply substrate manufactured by the manufacturing method shown in FIGS. 1 and 2. FIG. [Figure 4] 10A and 10B are explanatory views showing a part of a second embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 5] FIG. 10 is an explanatory view showing another part of the second embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 6] 10A and 10B are explanatory views showing a part of a third embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 7] 10A and 10B are explanatory views showing a part of a fourth embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 8] FIG. 10 is an explanatory view showing a part of a fifth embodiment of the method for manufacturing a light emitting diode supply board of the present invention. [Figure 9] 1A to 1C are explanatory diagrams showing an example of a conventional method for manufacturing a light-emitting diode supply board and an example of a conventional method for manufacturing a light-emitting diode display; DETAILED DESCRIPTION OF THE INVENTION

[0084] As described above, there has been a need for the development of a method for manufacturing a light-emitting diode supply board capable of manufacturing a light-emitting diode supply board on which a plurality of normal light-emitting diodes can be transferred to a supply destination either collectively or selectively, a method for manufacturing a high-yield light-emitting diode display, a method for manufacturing a divided unit of a high-yield light-emitting diode display, and a method for manufacturing an element supply board on which a plurality of normal elements can be transferred to a supply destination either collectively or selectively.

[0085] As a result of extensive research into the above-mentioned problems, the inventors discovered that the above-mentioned problems can be solved by a method for manufacturing a light-emitting diode supply board, which includes a selective removal step of selectively removing defective light-emitting diodes and a second mounting step of transferring normal light-emitting diodes to the positions where the defective light-emitting diodes had been located, and thus completed the present invention.

[0086] That is, the present invention provides a method for manufacturing a light emitting diode supply board for transferring a plurality of light emitting diodes to a supply destination, the method 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 a normal light-emitting diode to the position on the supply board where the defective light-emitting diode was located; The method for manufacturing a light emitting diode supply board includes the steps of:

[0087] The present invention also provides a method for manufacturing a light-emitting diode display, comprising the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; transferring the plurality of light emitting diodes on the light emitting diode supply substrate onto a display panel substrate; The method for manufacturing a light-emitting diode display is characterized by comprising the steps of:

[0088] Furthermore, the present invention provides a method for manufacturing a division unit of a light-emitting diode display, comprising the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; transferring the plurality of light emitting diodes on the light emitting diode supply board onto a division unit of a light emitting diode display; The method for manufacturing a division unit of a light-emitting diode display is characterized by comprising the steps of:

[0089] The present invention also provides a method for manufacturing an element supply substrate for transferring a plurality of elements to a supply destination, comprising the steps of: a first mounting step of mounting a plurality of elements on a supply substrate; a selective removal step of selectively removing defective elements on the supply substrate; a second mounting step of transferring a normal element to the position on the supply substrate where the defective element was located; The method for manufacturing an element supply substrate is characterized by comprising the steps of:

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

[0091] [Method of manufacturing the LED supply board] The present invention provides a method for manufacturing a light emitting diode supply board 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 a normal light-emitting diode to the position on the supply board where the defective light-emitting diode was located; The present invention is characterized by comprising:

[0092] In the method for manufacturing a light-emitting diode supply board of the present invention, in the selective removal step, defective light-emitting diodes are selected and removed from among the plurality of light-emitting diodes placed on the supply board in the first mounting step. Then, in the second mounting step, normal light-emitting diodes are transferred to the positions where the previously removed defective light-emitting diodes were placed. This manufacturing method makes it possible to manufacture a light-emitting diode supply board including only normal light-emitting diodes. By using the light-emitting diode supply board manufactured in this manner, multiple normal light-emitting diodes can be transferred to a supply destination collectively or selectively by laser lift-off or stamping. In other words, the manufacturing method for a light-emitting diode supply board of the present invention makes it possible to manufacture a light-emitting diode supply board capable of transferring multiple normal light-emitting diodes to a supply destination collectively. Furthermore, light-emitting diodes at desired positions on the light-emitting diode supply board manufactured by the present invention can be selected and transferred to the supply destination by laser lift-off. In other words, it is possible to manufacture a light-emitting diode supply board capable of transferring normal light-emitting diodes to any selected position.

[0093] Furthermore, since the LED supply board manufactured by the method for manufacturing an LED supply board of the present invention does not contain defective LEDs, the occurrence of defective light-emitting defects during the manufacture of LED displays or divided units of LED displays can be significantly reduced, thereby enabling the LED displays or divided units thereof to be manufactured with high yield and high efficiency.

[0094] Next, each step will be described in more detail.

[0095] [First loading process] In the first mounting step, a plurality of light emitting diodes are mounted on a supply substrate.

[0096] The supply substrate here may be, for example, 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] The light emitting diode may be one selected from the group consisting of a red light emitting diode, a green light emitting diode, and a blue light emitting diode. In this way, a single-color supply substrate for red, green, and blue light-emitting diodes can be manufactured.

[0098] It is preferable to use a light-emitting diode whose longest part is less than 300 μm. In this way, the inertial mass of the light-emitting diode is reduced, and it becomes possible to transfer it more efficiently by the laser lift-off method.

[0099] In the first mounting step, it is preferable that a plurality of light emitting diodes are adhered in a matrix pattern to the surface of the adhesive layer of the supply substrate. In this way, the supply substrates for the light-emitting diodes can be manufactured efficiently.

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

[0101] In this way, the supply substrate is moved only to a minimum extent without any unnecessary alignment movement, and the laser irradiation position is moved in a controlled manner, so that a plurality of light-emitting diodes can be transferred in a lump by the laser lift-off method.

[0102] The first mounting process is providing a starting substrate having the plurality of light emitting diodes fabricated thereon; separating the plurality of light-emitting diodes on the starting substrate into individual elements; transferring the plurality of light emitting diodes separated into individual elements onto the supply substrate; It is preferred that the compound contains: In this way, the first mounting step can be carried out efficiently.

[0103] Here, the starting substrate may be, for example, a sapphire substrate and a plurality of light-emitting diodes fabricated on the sapphire substrate.

[0104] The step of transferring the plurality of light emitting diodes in the first mounting step is preferably performed by a laser lift-off method. In this way, the first mounting step can be carried out more efficiently.

[0105] [Selective removal process] In the selective removal step, defective light emitting diodes on the supply substrate are selectively removed.

[0106] It is preferable to further include a determining step of determining whether or not each of the light emitting diodes on the supply board is normal before the selective removal step. By doing so, defective light emitting diodes can be more reliably removed in the selective removal step.

[0107] In this determination step, information on the positions of the defective light-emitting diodes may be recorded, for example, in a mapping format.

[0108] The determination step is preferably carried out by a photoluminescence method. When the determination step is performed by a photoluminescence method, the determination can be made without contact.

[0109] The photoluminescence method is a method in which a substance is irradiated with light and the light emitted when excited electrons return to the ground state is observed, and the observed optical information can be used to determine whether the substance or functional element electronic device is normal or abnormal. In the case of light-emitting diodes, one example is the INSPECTRA PL series from TASMIT.

[0110] Although the photoluminescence method is preferable because it is non-contact and has a fast judgment speed, if there is a method more preferable than the photoluminescence method for the object to be judged as normal / abnormal, another method may be used.When materials other than light-emitting diodes or electronic devices such as functional elements are targeted, a method suitable for each object to be judged may be used.

[0111] The selective removal step is preferably carried out by a laser lift-off method. When the selective removal step is performed by a laser lift-off method, only the defective light emitting diodes of the target can be easily removed, and as a result, light emitting diode supply substrates can be manufactured with higher efficiency.

[0112] When the selective removal step is performed by a laser lift-off method, it is preferable to shape the laser light 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, defective light emitting diodes can be selectively removed one by one by laser lift-off.

[0113] Furthermore, by scanning the laser light so that a different light emitting diode position is irradiated at each irradiation timing, defective light emitting diodes of the target can be selectively laser lifted off.

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

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

[0116] The second mounting process is preparing a supplemental substrate including a quartz substrate, an adhesive layer provided on the quartz substrate, and a plurality of light-emitting diodes adhered in a matrix on the surface of the adhesive layer; Transferring a normal light-emitting diode on the supplemental board to the position on the supply board from which the defective light-emitting diode was removed. It is preferable to carry out the process by the following method. In this way, the supply substrate for the light-emitting diode can be manufactured more efficiently.

[0117] Alternatively, the supplementary substrate may be, for example, a substrate similar to the starting substrate, including a sapphire substrate and a plurality of light-emitting diodes fabricated on the sapphire substrate.

[0118] It is preferable to further include, between the selective removal step and the second mounting step, an arrangement step of arranging a supplementary substrate so as to face the supply substrate. In this way, the accuracy in the second mounting step can be further improved.

[0119] In this case, in the above-mentioned arrangement step, it is preferable to align the positions of the defective light-emitting diodes on the supply board so that they face the positions of the normal light-emitting diodes on the supplemental board. This allows a normal light emitting diode to be mounted more accurately in the position where the defective light emitting diode was removed.

[0120] The second mounting step is preferably performed by a laser lift-off method. If the second mounting step is performed using the laser lift-off method, only the target light-emitting diodes that are normal can be selected and easily transferred to the positions where the defective light-emitting diodes were located, resulting in more efficient manufacturing of light-emitting diode supply boards.

[0121] When the second mounting step is performed by the laser lift-off method, it is preferable to shape the laser light to approximately the same size as the normal light-emitting diode to be transferred near the interface between the normal light-emitting diode to be transferred and the adhesive layer of the supplementary substrate. In this way, normal light emitting diodes can be selectively lifted off one by one with a laser, and the normal light emitting diodes can be more accurately transferred to the positions where the defective light emitting diodes were located.

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

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

[0124] In the method for manufacturing an LED supply board of the present invention, the board obtained in the second mounting step may be used as the LED supply board as is. Alternatively, a plurality of LEDs may be transferred from one or more boards obtained in the second mounting step to another board, and the resulting board may be used as the LED supply board. Specific examples of each method will be described later.

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

[0126] [Supply board] The planar shape of the supply substrate may be circular or rectangular. Of course, the most suitable shape may be used depending on the purpose. When the supply substrate is simply used as a supply substrate for normal light-emitting diodes, the most efficient way to provide a supply substrate for light-emitting diodes is to use a circular supply substrate that inherits the pattern layout used during light-emitting diode manufacturing. On the other hand, if the focus is on an LED supply substrate for manufacturing a final display, a supply substrate shape that corresponds to divided units, so-called tiles, that are divided into integer fractions of the desired display screen (shape, aspect ratio) while maintaining the desired display screen. In this way, it is preferable to provide a supply substrate with a shape that is suitable for the final product, such as an electronic device, to be manufactured.

[0127] The quartz substrate and adhesive layer that can be used in the donor substrate and any supplemental substrates will now be described in more detail.

[0128] [Quartz substrate] The supply substrate and any supplementary substrates may include a quartz substrate, which provides high transmittance for the short wavelength UV laser light that causes laser ablation. Preferably, the quartz substrate is a synthetic quartz substrate.

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

[0130] Another benefit of using synthetic silica glass is its thermal stability. That is, synthetic silica glass substrates have a thermal expansion coefficient that is approximately one-fifth that of other quartz glass substrates, which reduces thermal distortion during operation. In particular, in the case of stamp components with convex protrusions, this reduces misalignment and distortion of the protrusion position due to thermal expansion and contraction, enabling accurate laser lift-off transfer operations.

[0131] It is also preferable to provide a facet at at least one vertex on the front or back side of the quartz substrate, or to provide a mark indicating the orientation of the quartz substrate on the front, back, or side of the periphery of the quartz substrate, so that the supply substrate can be set in the correct rotational position when it is placed in a transfer device using the laser lift-off method.

[0132] Furthermore, by engraving characters, symbols, 2D barcodes, etc. into the quartz substrate, it becomes possible to manage individual supply substrates. Note that these characters, symbols, 2D barcodes, etc. may also be used as marks for orientation. The facets may also be used as marks for indicating orientation.

[0133] [Adhesive layer] The adhesive layer is preferably made of a silicone-based pressure-sensitive adhesive, which does not cause ablation at the interface. Examples of silicone-based pressure-sensitive adhesives include PDMS (polydimethylsiloxane), silicone compositions modified at the side chains and both ends of PDMS, and combinations thereof. Physical properties such as material hardness, pressure-sensitive adhesive strength, and repeated adhesion can be controlled by adjusting the composition of each material (molecular weight, modifying group, modifying substance, modification amount, etc.) and, in the case of a mixture, the mixing ratio. In addition to mixing, various modified silicone compositions can also be optimized by crosslinking or three-dimensional molecular structuring. When a silicone-based pressure-sensitive adhesive is optimized for the process of the present invention, the organic adhesive layer does not remain on the light-emitting diode when the light-emitting diode is peeled from the adhesive layer by laser ablation using a laser lift-off method, as is the case when organic materials, such as polyimides and acrylic pressure-sensitive adhesives, whose main chains are primarily organic skeletons, are used as adhesive layers. As a result, it becomes possible to repeatedly mount light-emitting diodes in the same location, which was previously impossible with adhesive layers made of organic compositions.

[0134] The adhesive principle of silicone-based pressure-sensitive adhesives is that tackiness is generated by the adhesive strength inherent to the material and pressure (external force acting as pressure). A pressure displacement of a few microns to 5 μm is sufficient to generate tackiness, so a thickness of around 5 to 10 μm is sufficient. Of course, there is no problem if the thickness is thicker than that.

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

[0136] When a laser lift-off method is used in the selective removal step, the second mounting step, or both, the laser is preferably an excimer laser.

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

[0138] When the laser lift-off method is used in the selective removal step, the second mounting step, or both, it is preferable to use a pulsed laser and perform lift-off by irradiating with one pulse of laser light, for the reasons explained below.

[0139] When a CW laser is used in the laser lift-off method, the energy per wavelength is low, and long-term laser irradiation is required to remove the light-emitting diode by laser ablation. Thus, even if removal is possible with a CW laser, the laser energy at the moment of removal is also small, making it difficult to transfer the light-emitting diode from the supply substrate to the receiving substrate. In contrast, a pulsed laser can emit high-energy pulsed laser light that is time-compressed, allowing laser ablation to occur instantly with a single pulse. As a result, the force that transfers the light-emitting diode from the supply substrate to the receiving substrate is large, and this force is exerted instantaneously, making it ideal for transferring light-emitting diodes using the laser lift-off method.

[0140] Among pulsed lasers, excimer lasers are particularly preferred. The most practical types of excimer lasers are XeCl (308 nm), KrF (248 nm), and ArF (193 nm). For example, the LAMBDA SX, available from COHERENT, is an example of an XeCl excimer laser. It outputs a maximum pulse energy of 1000 mJ and is available in systems with maximum pulse repetition rates of 500 Hz (500 W) and 600 Hz (600 W).

[0141] Examples of KrF and ArF excimer lasers include the IndyStar series sold by COHERENT. KrF has a maximum output of 12 W and can be operated at a maximum pulse repetition rate of 1 kHz with a maximum pulse energy of 12 mJ. Furthermore, it can be operated at a maximum pulse repetition rate of 2 kHz with a maximum pulse energy of 6 mJ.

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

[0143] When the pulse repetition frequency is 1 kHz, the pulse time interval is 1 msec. In reality, the stage movement time is the rate-limiting factor in the manufacturing method of the LED supply board of the present invention because the time for the placement step is added, but compared to the stamping method, it allows for extremely high-speed transfer. Furthermore, in the selective removal step and second mounting step of the manufacturing method of the LED supply board of the present invention, the primary objectives are to remove defective LEDs and mount normal LEDs in their places, rather than to transfer all the LEDs arranged on the entire substrate at once, so this method is extremely useful for manufacturing a supply board that does not contain defective LEDs.

[0144] Furthermore, although the energy of excimer laser light itself is high, the time width of one pulse is compressed to an extremely short time, 24 nsec (FWHM) for XeCl and 7 nsec (FWHM) for KrF and ArF, which has the advantage of being less likely to cause damage to the laser-irradiated area.

[0145] It should be noted that if there is a pulse laser other than an excimer laser that has sufficient performance to realize the present invention, it may also be used.

[0146] In this way, the laser used in the selective removal step, the second mounting step, or both does not have to be limited to an excimer laser, and any laser capable of generating pulsed laser light of the required intensity can be used.

[0147] When the step of transferring a plurality of light emitting diodes collectively in the first mounting step is performed by the laser lift-off method, the laser to be used is not particularly limited, and may be a CW laser.

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

[0149] Generally, light-emitting diodes with short sides of 100 μm to 300 μm are called mini light-emitting diodes, while those with short sides of 100 μm or less, or even 50 μm or less, are called micro light-emitting diodes. Recently, some companies have prioritized commercial merit and have begun calling light-emitting diodes measuring 150 μm x 150 μm micro light-emitting diodes. While it is difficult to accurately define these scales, the light-emitting diodes to be transferred in this invention are referred to as mini light-emitting diodes or micro light-emitting diodes.

[0150] For example, miniature light-emitting diodes measuring 100 μm x 200 μm in length and width were previously less than 100 μm in height, but recently, thin-film blue and green miniature light-emitting diodes measuring 150 μm x 150 μm x just under 10 μm in height have begun to appear. Correspondingly, red miniature light-emitting diodes are available that are just under twice as tall. In the case of micro light-emitting diodes with a planar size of less than 100 μm x 100 μm, the thickness has further progressed, reaching less than 10 microns including the electrodes, and in some cases as small as 7 microns. Planar sizes of light-emitting diodes as small as 25 μm x 25 μm x 7 μm in height are already available.

[0151] When transferring the above-mentioned mini and micro LEDs using the laser lift-off method, it is advisable 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 is adjusted to approximately three times the length of one side of the planar size or less, and more preferably, it is adjusted to approximately two times the length of one side of the planar size or less. If the flight distance is 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 may be a spot size approximately the same as or slightly larger than the size of the target LED.

[0152] Of course, it can be about the same as the length of one side of the planar size, or even less. Although this is difficult to achieve with an ordinary quartz substrate, by using a synthetic quartz substrate with an in-plane film thickness uniformity of 1 μm or less as the base material of the supply substrate, it is possible to make the gap between the supply substrate and the receiving substrate several tens of microns. The limiting distance of this gap depends on the capacity of the equipment that handles the supply substrate and the receiving substrate.

[0153] On the LED supply board, a plurality of LEDs may be arranged such that one or more red LEDs, one or more green LEDs, and one or more blue LEDs form a set of pixels.

[0154] For example, in the second mounting step, a supply substrate for a red light-emitting diode, a supply substrate for a green light-emitting diode, and a supply substrate for a blue light-emitting diode are prepared, and these supply substrates can be used to transfer the red light-emitting diode, the green light-emitting diode, and the blue light-emitting diode onto further supply substrates so that one or more of each constitutes a set of pixels.

[0155] In this way, when manufacturing a light-emitting diode display, transfer and mounting can be performed all at once or in units of one pixel.

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

[0157] (First embodiment) 1 and 2 are diagrams illustrating a first embodiment of the method for manufacturing a light emitting diode supply board according to the present invention.

[0158] In FIG. 1, 1 denotes a first sapphire substrate serving as a starting substrate, and 2 denotes a light-emitting diode, which is manufactured on the starting substrate (first sapphire substrate) 1 and then singulated. 3 denotes an electrode provided on the light-emitting diode 2. 4 denotes a first supply substrate, which includes a substrate 41 made of a quartz substrate and an adhesive layer 42 formed on one surface thereof. 6 denotes a laser beam. 7 denotes a container for collecting defective light-emitting diodes 2'. 8 denotes a second sapphire substrate serving as a supplementary substrate. Similar to the starting substrate 1 in FIG. 1(a), the supplementary substrate (second sapphire substrate) 8 includes a singulated light-emitting diode 9 on which an electrode 3 is formed. In FIG. 2, 5 denotes a second supply substrate, which includes a substrate 51 made of a quartz substrate and an adhesive layer 52 formed on one surface thereof.

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

[0160] (1st loading process) First, an example of the first mounting step of mounting a plurality of light emitting diodes on a supply substrate will be described with reference to FIG. 1(a).

[0161] As shown in FIG. 1(a), the surface (front surface) of the first supply substrate 4 on which the adhesive layer 42 is provided and the surface (front surface) of the starting substrate 1 on which the light-emitting diodes 2 are fabricated are arranged parallel to each other and adjusted to a constant distance within the 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 diodes 2 are not fabricated) and this laser light 6 is focused near the interface between the desired light-emitting diodes 2 and the starting substrate 1. If the light-emitting diodes 2 are blue or green light-emitting diodes, the GaN layer of the light-emitting diodes 2 exists at the interface between the starting substrate 1 and the light-emitting diodes 2 fabricated on the starting substrate 1. When the laser light 6 reaches this layer, a portion of the GaN layer evaporates due to laser ablation, and the light-emitting diodes 2 are separated from the starting substrate 1. This method is a form of laser lift-off. The separated light-emitting diodes 2 fly toward the adhesive layer 42 of the opposing first supply substrate 4 and are attached and fixed to the adhesive layer 42. As shown in Fig. 1(a), all of the light-emitting diodes 2 are transferred at once from the starting substrate 1 to the surface of the adhesive layer 42 of the first supply substrate 4 while moving a laser beam 6 along the rear surface of the starting substrate 1. Fig. 1(b) shows the state in which all of the desired light-emitting diodes 2 have been transferred in this manner.

[0162] 1(a), when the laser lift-off method is performed using a CW laser in the step of transferring a plurality of light-emitting diodes at once in the first mounting step, it is advisable to perform the step with the electrode portions 3 of the light-emitting diodes 2 pressed against the adhesive layer 42 (not shown). In this way, it becomes possible to transfer the light-emitting diodes at once by laser lift-off even with a CW laser.

[0163] (Selective removal process) Next, an example of a process for selectively removing defective light-emitting diodes will be described with reference to FIG. 1(c).

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

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

[0166] The positions 10 of the defective light emitting diodes 2' may be determined in advance on the starting substrate 1 as normal / defective in the determination step described above, and the position information may be recorded as a mapping.

[0167] (2nd loading process) Next, an example of the second mounting step of transferring a normal light emitting diode to the position where the defective light emitting diode was located on the supply board will be described with reference to FIG. 1(d).

[0168] As shown in Figure 1(d), the surface (adhesive layer 42) of the first supply substrate 4 is placed upward (opposite to gravity), and a supplementary substrate (second sapphire substrate) 8 is placed on top of it with its surface facing downward, so that they are parallel and facing each other at a certain distance. At the same time, the rotation of the X-Y axes of the surface of the first supply substrate 4 and the X-Y axes of the surface of the supplementary substrate 8 is corrected, and alignment control is performed so that the position of the normal light-emitting diode 9 on the supplementary substrate 8 to be supplemented 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 supplemented). At the same time, the distance between the surface of the supplementary substrate 8 and the surface of the first supply substrate 4 is adjusted in the Z-axis direction so that it is optimal. That is, the manufacturing method of the light-emitting diode supply board of the first embodiment further includes an arrangement step between the selective removal step and the second mounting step, in which the supplementary board 8 is arranged so as to face the first supply board 4, and in this arrangement step, the position 10 where the defective light-emitting diode 2' was arranged on the first supply board 1 is aligned with the position of the normal light-emitting diode 9 on the supplementary board 8 so as to face each other.

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

[0170] Next, after the above placement step is completed, laser light 6 is irradiated onto the normal light emitting diodes 9 from the back surface of the supplementary substrate 8, and the supplementary substrate 8 is transferred to the light emitting diode missing portion (the position where the defective light emitting diode 2' was placed) 10 of the first supply substrate 4 by laser lift-off. This is also a form of laser lift-off (second mounting step).

[0171] By repeatedly performing the above-described arrangement step and second mounting step, it is possible to manufacture a first light-emitting diode supply board 100 that does not include any defective light-emitting diodes 2', as shown in FIG. 1(e).

[0172] The positions of the normal light emitting diodes 9 may be determined in advance as normal or defective on the supplementary board 8, and the position information may be recorded in a mapping format.

[0173] (Inversion process) In the state shown in Figure 1(e), the electrode 3 side of the light emitting diodes 2 of the first light emitting diode supply substrate 100 faces the adhesive layer 5 side, so it cannot be used as is for transferring to a light emitting diode display panel. Therefore, all of the light emitting diodes 2 must be further turned over. The turning step performed here will be described below.

[0174] First, a second supply substrate 5 shown in FIG. 2(f) is prepared. Next, as shown in FIG. 2(f), the adhesive layer 42 side (surface) on which the light-emitting diodes 2 are mounted of the first supply substrate 4 is placed downward on the surface (surface) on which the adhesive layer 52 is provided of the second supply substrate 5, so that they face each other in parallel at a certain distance. In this state, a 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 FIG. 2(g).

[0175] Thus, according to the first embodiment of the present invention, the first and second light-emitting diode supply boards 100 and 200 that do not include any 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 roughly described with reference to FIG.

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

[0178] In this state, as shown in Fig. 3(h), a plurality of light-emitting diodes 2 are transferred and arranged en bloc from the second light-emitting diode supply substrate 200 to the display panel substrate 39 by laser lift-off in the same procedure as that described with reference to Fig. 9(IV). By subsequently making electrical connections, it is possible to obtain a light-emitting diode display (or a light-emitting diode display panel as a divided unit thereof) 300, which includes the display panel substrate 39 and a plurality of light-emitting diodes 2 arranged on this substrate, as shown in Fig. 3(i).

[0179] Although not shown, a stamping method can also be used to transfer and arrange a plurality of light emitting diodes 2 from the second light emitting diode supply substrate 200 onto the display panel substrate 39 at once.

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

[0181] In this way, by using the LED supply board manufactured by the first embodiment of the method for manufacturing an LED supply board of the present invention, it is possible to manufacture an LED display with extremely few light emitting defects.

[0182] If the process of transferring the light emitting diodes 2 en bloc 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 process enables contactless, high-speed bulk transfer and practically high-efficiency production of the light emitting diode display 300. In this way, the light emitting diode supply substrate 200 manufactured by the method for manufacturing a 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 and micro light emitting diode displays.

[0183] Furthermore, in the manufacturing stage of the second light-emitting diode supply substrate 200, it is preferable to manufacture the second light-emitting diode supply substrate 200 so that it is laid out with at least one red light-emitting diode, one green light-emitting diode, and one blue light-emitting diode for each color at the pixel pitch required for the display, thereby forming an RGB light-emitting diode group for one pixel. To achieve this, a first supply substrate 100 for the light-emitting diodes 2 of each RGB color is used, and the transfer position onto the second supply substrate 5 is controlled for each color, so that the RGB light-emitting diodes are arranged at the display pitch and so as to match the electrode positions on the display panel substrate 39. In this way, if the second light-emitting diode supply substrate 200 is manufactured so as to have a pixel configuration and pixel pitch that match 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 at once.

[0184] Furthermore, it is preferable that the light emitting diodes 2 are arranged so that the pitch of the arrangement matrix (XY) of each of the RGB colors is the pixel pitch of the display panel or 1 / Nth of the pixel pitch P.

[0185] To achieve this, the light emitting diodes 2 may be transferred and mounted at the desired pixel pitch P or P / N pitch positions 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 / (an integer number N) of the desired pixel pitch P and at a pitch at which the light emitting diodes 2 do not overlap, it is possible to manufacture the second light emitting diode supply substrate 200 with the maximum mounting amount corresponding to the desired pixel pitch.

[0186] In this way, by using the second light-emitting diode supply board 200 on which the light-emitting diodes 2 are mounted at P / N (N: integer) pitch positions, the transfer speed can be significantly improved when mounting the light-emitting diodes 2 on the display panel board 39. That is, when transferring the light-emitting diodes from the second light-emitting diode supply board 200 to the display panel board 39 by the laser lift-off method, the laser irradiation position is optically moved to selectively transfer the light-emitting diodes 2 at the desired pixel pitch positions on the XY matrix, thereby allowing a plurality of light-emitting diodes 2 to be transferred at once (all at once) in an arrangement 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 (the pitch position of the display panel), and transfer is performed by the selective laser lift-off method. By repeating this series of operations, it is possible to manufacture a light-emitting diode display panel having light-emitting diodes 2 at pixel pitch positions at approximately N times the speed. By sequentially performing the series of operations for each light-emitting diode of each color, it is possible to manufacture an RGB light-emitting diode display 300 or a display division unit (e.g., a light-emitting diode display panel) 300.

[0188] As described above, if a light-emitting diode supply board is manufactured in a position suitable for mounting and assembling light-emitting diodes on a display during the manufacturing stage of the light-emitting diode supply board, manufacturing efficiency can be further improved in the manufacturing and assembly process of the display or the display division units.

[0189] In addition, when transferring LEDs 2 en bloc from the starting substrate 1 to the first supply substrate 4 using the laser lift-off method (FIG. 1(a)), and when transferring LEDs 2 en bloc from the first supply substrate 4 to the second supply substrate 5 (FIG. 2(f)), operations without stage movement are preferable from a practical standpoint of time. In such cases, transferring LEDs 2 en bloc within a practical timeframe can be achieved by scanning the laser beam 6. The high repetition rate of the excimer laser is particularly effective. Furthermore, because of the high output of the laser beam, the laser beam spot size can be expanded to cover multiple LEDs 2, rather than transferring each LED 2 individually. The spot shape can be either square or rectangular. The laser light irradiation is synchronized with the pulse oscillation frequency or an integral multiple thereof, and unnecessary pulse oscillation light is blocked by an optical shutter, thereby enabling efficient transfer of the light emitting diodes.

[0190] (Second embodiment) 4 and 5 are diagrams illustrating a method for manufacturing a light emitting diode supply board according to a second embodiment of the present invention.

[0191] The first embodiment described above is characterized by the steps of selectively removing defective LEDs 2' and transferring normal LEDs 9 on the first supply substrate 4, as shown in FIGS. 1(c) and 1(d). The second embodiment shown in FIGS. 4 and 5 is characterized by the steps of selectively removing defective LEDs 2' and transferring normal LEDs 9 on the second supply substrate 5, as shown in FIGS. 5(e2) and 5(f2). Another difference is that the third supply substrate 11, which serves as a supplementary substrate, is used to supply normal LEDs 9. The third supply substrate 11 may be fabricated similarly to the first supply substrate 4 shown in FIG. 4(b2). Naturally, the normal / abnormal status of the LEDs 2 and 9 previously determined on the starting substrate 1 and their positional information are carried over when the LEDs 2 and 9 are collectively transferred from the starting substrate 1 to the first supply substrate 4 and the third supply substrate 11.

[0192] 1(e) of the first embodiment, i.e., the first LED supply board 100 in which the defective LEDs 2' have been removed and all normal LEDs 2 are mounted, can be used as the third supply board 11 shown in Fig. 5(f2) in the second embodiment of the present invention, whereby all the LEDs 2 on the first LED supply board 100 can be used without distinction. As a result, the efficiency of the arrangement step on the second supply board 5 and the second mounting step shown in Fig. 5(f2) can be improved.

[0193] (Third embodiment) FIG. 6 shows a part of an explanatory diagram of a method for manufacturing a light emitting diode supply board according to the third embodiment of the present invention, and extracts points different from the second embodiment of the present invention.

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

[0195] The second light-emitting diode supply substrate 200 shown in FIG. 6(g') obtained by the process of FIG. 6(f') is similar to those shown in FIG. 2(g) and FIG. 5(g2).

[0196] (Fourth embodiment) In the first to third embodiments, the first mounting step is shown in FIGS. 1(a) and 4(a2), which illustrates a step of transferring a plurality of light-emitting diodes 2 collectively from a starting substrate 1 on which the light-emitting diodes 2 have been manufactured to a first supply substrate 4. This can be achieved in the case of blue and green light-emitting diodes 2 because the interface between the starting 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 N is sublimated, causing the light-emitting diodes 2 to peel off from the starting substrate 8 and be ejected. Furthermore, this is possible in the case of blue and green light-emitting diodes because of their lateral structure in which electrodes are formed on the same surface.

[0197] However, in the case of red diodes, the starting substrate itself is formed on a GaAs substrate, and electrodes are usually formed to sandwich the light-emitting diode, a so-called vertical structure. If this is mounted on a display panel as is, there is a problem that the electrode connection becomes even more complicated because it is a structure different from the lateral structure of blue and green light-emitting diodes. To overcome this problem, lateral structure red light-emitting diodes have been produced and distributed in recent years.

[0198] FIG. 7 is a partial explanatory view of a method for manufacturing a light emitting diode supply board according to the fourth embodiment of the present invention.

[0199] In Figure 7, 21 is a starting substrate (sapphire substrate), and 22 is a red light-emitting diode. 23 and 24 are electrodes provided on the light-emitting diode, and electrodes 23 and 24 are each connected to a conductive layer on the opposite surface of red diode 22. In this way, red light-emitting diode 22 has electrodes configured in a lateral structure. Red light-emitting diode 22 is fixed to starting substrate 21 by adhesive layer 25. A resin such as BCB (Benzocyclobutene) is generally used for adhesive layer 25. Furthermore, 4 is a first supply substrate, which includes substrate 41 and adhesive layer 42 formed thereon.

[0200] 7(a4), the starting substrate 21 and the first supply substrate 4 are arranged parallel to each other and are adjusted to have a constant in-plane distance. In this state, a part of the adhesive layer 25 is ablated by laser lift-off, and the red light-emitting diode 22 fixed to the starting substrate 21 by the adhesive layer 25 is transferred to the first supply substrate 4.

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

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

[0203] The normal / failure determination of the red light emitting diode 22 may be performed by a photoluminescence method while the red light emitting diode 22 is fixed to the starting substrate 1.

[0204] As described above, it is possible to manufacture light-emitting diode supply substrates for manufacturing light-emitting diode displays for blue, green, and red light-emitting diodes.

[0205] (Fifth embodiment) In the first to fourth embodiments, in the first mounting step, a laser lift-off method is used to scan a laser beam 6 with a certain gap between the starting substrate 1 and the first supply substrate 4, and the light-emitting diodes 2 or 22 of each color are mounted collectively on the first supply substrate 4. Also, when the light-emitting diodes 2 or 22 are transferred collectively from the first supply substrate 4 to the second supply substrate 5, a certain gap is provided between the two substrates. The advantage of this method is that the same adhesive material can be used for the adhesive layers on the first supply substrate 4 and the second supply substrate 5.

[0206] However, batch transfer is possible even if there is no gap.

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

[0208] Figure 8(a 5-1 ), Fig. 8(a 5-2 8(f5), when the light-emitting diodes 2 or 22 are transferred by the laser lift-off method without leaving any gaps, it is advisable to apply a slight pressure to the adhesive layers 42 and 52 to obtain a tacking effect.

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

[0210] In the case of FIG. 8(f5), by using a material for the adhesive layer 52 having a greater adhesive strength (including tackiness) than the adhesive layer 42, collective transfer by the laser lift-off method is realized.

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

[0212] By using the second light-emitting diode supply board 200 manufactured by the manufacturing method for a light-emitting diode supply board 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 FIG. 3, in the same way as in the case where the second light-emitting diode supply board 200 manufactured by the manufacturing method for a light-emitting diode supply board according to the first embodiment is used.

[0213] [Method for manufacturing a light-emitting diode display and a method for manufacturing a division unit of a light-emitting diode display] The method for manufacturing a light-emitting diode display of the present invention includes the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; transferring the plurality of light emitting diodes on the light emitting diode supply substrate onto a display panel substrate; The present invention is characterized by having the following.

[0214] Further, a method for manufacturing a division unit of a light-emitting diode display of the present invention includes the steps of: manufacturing the LED supply board by the LED supply board manufacturing method of the present invention; transferring the plurality of light emitting diodes on the light emitting diode supply board onto a division unit of a light emitting diode display; The present invention is characterized by having the following.

[0215] In the method for manufacturing an LED display and a method for manufacturing a divided unit of an LED display of the present invention, an LED supply substrate is manufactured by the method for manufacturing an LED supply substrate of the present invention, and then a plurality of LEDs are transferred to an LED display substrate or a divided unit of an LED display using the LED supply substrate, thereby making it possible to efficiently manufacture an LED display or a divided unit of an LED display that does not contain defective LEDs. That is, the method for manufacturing an LED display of the present invention makes it possible to manufacture LED displays with a high yield. Furthermore, the method for manufacturing a divided unit of an LED display of the present invention makes it possible to manufacture divided units of an LED display with a high yield.

[0216] The step of transferring the plurality of light emitting diodes on the light emitting diode supply substrate onto the display panel substrate is preferably performed by a laser lift-off method. In this way, a plurality of light emitting diodes can be transferred at higher speed, and therefore a more practical method for manufacturing a light emitting diode display can be provided.

[0217] Similarly, the step of transferring the plurality of light emitting diodes on the light emitting diode supply board onto the division unit of the light emitting diode display is preferably performed by a laser lift-off method. In this way, a plurality of light emitting diodes can be transferred at higher speed, and therefore a more practical method for manufacturing divided units of a light emitting diode display can be provided.

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

[0219] The method for manufacturing an LED display and a divided unit of an LED display of the present invention can manufacture, for example, a high-resolution, large-screen display and divided units thereof. However, the method for manufacturing an LED display and a divided unit of an LED display of the present invention can provide display function units for wristwatch-sized healthcare devices, composite devices, in-vehicle head-up displays and navigation system displays, visual augmentation devices such as AR / VR / MR, and eyeglass-type display devices by using an LED supply board manufactured by the method for manufacturing an LED supply board of the present invention. As a result, electrical and electronic devices equipped with the above-mentioned LED displays or divided units thereof can be manufactured and provided with a high yield.

[0220] [Method of manufacturing element supply board] The method for manufacturing an element supplying substrate of the present invention is a method for manufacturing an element supplying substrate for transferring a plurality of elements to a supply destination, comprising the steps of: a first mounting step of mounting a plurality of elements on a supply substrate; a selective removal step of selectively removing defective elements on the supply substrate; a second mounting step of transferring a normal element to the position on the supply substrate where the defective element was located; The present invention is characterized by comprising:

[0221] In the method for manufacturing an LED supply board of the present invention, if elements such as microelectric elements or microsemiconductor chips are applied instead of LEDs, an element supply board can be manufactured that can be used for three-dimensional packaging and the manufacture of electrical and electronic equipment.

[0222] By using an element supply board manufactured in this manner, a plurality of normal elements can be transferred to a destination in a batch by laser lift-off or stamping. That is, according to the method for manufacturing an element supply board of the present invention, an element supply board capable of transferring a plurality of normal elements to a destination in a batch can be manufactured. Furthermore, elements at desired positions on an element supply board manufactured according to the present invention can be selected and normal elements can be transferred to the destination by laser lift-off. That is, an element supply board capable of transferring normal elements to any selected position can be manufactured.

[0223] Such a method for manufacturing an element supply board can be used, for example, in three-dimensional packaging and in the manufacture of electric and electronic devices.

[0224] Microelectric elements include resistors, capacitors, and inductors. Microsemiconductor 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] The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits 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'...defective light-emitting diode, 3, 23, 24...electrodes, 4...first supply substrate, 5...second supply substrate, 6...laser light, 7...container, 8...replenishment substrate, 9...normal light-emitting diode, 10...position where defective light-emitting diode was placed, 11...third supply substrate, 22...red light-emitting diode, 25...adhesive layer, 42, 52...adhesive layer, 39...supply 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 a plurality of elements to a supply destination, comprising: a first mounting step of mounting a plurality of elements on an adhesive layer of a supply substrate having an adhesive layer on one surface of the supply substrate; a selective removal step of selectively removing defective elements from among the plurality of elements on the supply substrate by irradiating them with laser light; a second mounting step in which the defective element is removed and a normal element is re-adhered to the exposed adhesive layer; A method for manufacturing an element supply substrate, comprising:

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

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

4. 4. The method for manufacturing an element supply board according to claim 1, wherein the adhesive layer is formed from a pressure-sensitive adhesive containing silicone as a main component.

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 PDMS, a silicone composition in which the side chains and both ends of PDMS are modified, or a composition consisting of a combination thereof.

6. A method for manufacturing an electric 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. The method for manufacturing an electrical device according to claim 6, further comprising the step of turning the element over.

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. The method for manufacturing an electronic device according to claim 8, further comprising the step of turning the element over.

10. A three-dimensional mounting method 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.

11. The three-dimensional packaging method according to claim 10, further comprising the step of turning the element over.

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