JP7269548B2 - Holding member, transfer member, chip substrate, transfer member manufacturing method and manufacturing apparatus, light emitting substrate manufacturing method - Google Patents

Description

The present invention relates to a holding member, a transfer member having the holding member, a chip substrate used for manufacturing the transfer member, a method for manufacturing the transfer member, an apparatus for manufacturing the transfer member, and a method for manufacturing a light emitting substrate using the transfer member.

2. Description of the Related Art In recent years, so-called micro-LED displays, which use a light-emitting substrate in which a plurality of micro-light-emitting diode (LED) chips are arranged on a circuit board having a circuit, have been developed. Micro LED displays are superior to liquid crystal displays and the like in terms of brightness, power consumption, response speed, reliability, etc., and are attracting attention as next-generation lightweight and thin displays.

Conventionally, when manufacturing light-emitting substrates used in micro-LED displays, a plurality of micro-light-emitting diode chips formed by dicing a wafer are arranged one by one on a circuit board by a pick-and-place process. In such a light-emitting substrate manufacturing method, the pick-and-place process is repeated millions of times or more, and the process of arranging the micro-light-emitting diode chips on the circuit board takes a long time, thereby increasing the manufacturing cost. end up That is, the light-emitting substrate can only be manufactured with low productivity.

Therefore, as disclosed in Japanese Unexamined Patent Application Publication No. 2002-100000, it was considered to dispose the micro-light-emitting diode chips from the wafer to the circuit board by means of an adhesive stamp. Since the adhesive stamp of Patent Document 1 can hold a plurality of micro light emitting diode chips, a plurality of micro light emitting diode chips can be arranged on a circuit board in one pick-and-place process. Therefore, the time required for the process of disposing the micro LED chip on the circuit board can be shortened, and the manufacturing cost can be reduced.

Japanese Patent Application Publication No. 2017-531915

By the way, the adhesive stamp of Patent Document 1 loses adhesiveness when the pick-and-place process is repeated. As the tackiness of the adhesive stamp decreases, the reliability of the adhesive stamp holding the micro-light emitting diode chip during the pick-and-place process decreases. For this reason, a step of imparting adhesiveness to the adhesive stamp and a step of exchanging the adhesive stamp are required, which makes it difficult to improve the productivity of manufacturing the light-emitting substrate.

Therefore, the inventors of the present invention conducted a study to make it possible to arrange the micro light emitting diode chips from the wafer to the circuit board without repeating the pick and place process, and furthermore, to collectively assemble the micro light emitting diode chips on the circuit board. A holding member for holding a micro light emitting diode chip, a transfer member for a micro light emitting diode chip having the holding member, a method for manufacturing the transfer member, and a manufacturing method for a light emitting substrate using the transfer member I found a way. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to improve the productivity of a light emitting substrate having a plurality of micro light emitting diode chips arranged thereon.

In order to solve the above problems, a holding member of the present invention is a holding member for holding a plurality of light-emitting diode chips of two or more types, comprising a plate-like substrate and a a plurality of projecting holding parts arranged regularly two-dimensionally and each holding one of the light emitting diode chips, wherein the projecting holding part comprises a projecting structure that is a main body; It has a first adhesive layer provided at the tip of the body, and can be compressed and deformed in a direction perpendicular to the plate surface of the base material by the thickness of the light emitting diode chip or more. A Young's modulus of the protruding structure may be 10 GPa or less, and a length of the protruding structure in a direction perpendicular to the plate surface of the substrate may be 5 μm or more. The adhesiveness of the first adhesive layer may be reduced by heating, cooling, or ultraviolet irradiation.

The transfer member of the present invention includes the holding member and the plurality of light emitting diode chips of two or more types held by the projecting holding portion.

The chip substrate of the present invention is used for holding the light-emitting diode chip on the holding member, and comprises a plate-like chip substrate and a second adhesive layer laminated on one surface of the chip substrate. and a plurality of the light-emitting diode chips regularly arranged two-dimensionally on the surface of the second adhesive layer opposite to the surface facing the chip substrate, wherein the second adhesive layer is attached to the holding member. Adhesiveness is higher than that of the first adhesive layer, and adhesiveness becomes lower than that of the first adhesive layer of the holding member by ultraviolet irradiation, laser irradiation, heating, or cooling. The chip base material may transmit ultraviolet rays, and the adhesiveness of the second adhesive layer may be reduced by ultraviolet irradiation. An integral multiple of the pitch of the array of the light emitting diode chips may be the pitch of the array of the projecting holding portions.

The method for producing a transfer member of the present invention comprises a plate-shaped chip substrate, and a second adhesive which is laminated on one plate surface of the chip substrate and whose adhesiveness is reduced by ultraviolet irradiation, laser irradiation, heating or cooling. and a plurality of first light emitting diode chips regularly arranged two-dimensionally on the surface opposite to the surface of the second adhesive layer facing the chip substrate. 4. A first step of contacting the holding member according to any one of 3; and contacting the projecting holding portion for holding the first light emitting diode chip in the second adhesive layer of the first chip substrate. a second step of reducing the adhesiveness of the region where the first light emitting diode chip is arranged by ultraviolet irradiation, laser irradiation, heating or cooling ; a third step of holding the first light-emitting diode chip on the projecting holding portion; a plate-shaped chip base; A second adhesive layer with low adhesiveness and a plurality of first light-emitting diode chips that are regularly two-dimensionally arranged on the surface of the second adhesive layer opposite to the surface of the second adhesive layer facing the chip substrate. a fourth step of contacting a second chip substrate having a second light emitting diode chip with the holding member; and a fourth step of holding the second light emitting diode chip on the second adhesive layer of the second chip substrate. a fifth step of reducing the adhesiveness of a region where the second light-emitting diode chip is arranged and in contact with the projecting holding portion by ultraviolet irradiation, laser irradiation, heating, or cooling; and holding the second chip substrate. and a sixth step of separating the second light emitting diode chip from the member and holding the second light emitting diode chip on the projecting holding portion. The chip base materials of the first chip substrate and the second chip substrate transmit ultraviolet rays, and the adhesiveness of the second adhesive layers of the first chip substrate and the second chip substrate decreases due to ultraviolet irradiation. In the second step and the fifth step, a shielding portion for shielding ultraviolet rays from the side opposite to the second adhesive layer side of the first chip substrate or the second chip substrate; A step of irradiating the second adhesive layer through a photomask having a transmission portion that transmits ultraviolet rays may be included.

An apparatus for manufacturing a transfer member according to the present invention includes a plate-like chip base material, a second adhesive layer laminated on one surface of the chip base material and whose adhesiveness is reduced by ultraviolet irradiation, and the second adhesive layer. a plurality of the light-emitting diode chips regularly arranged two-dimensionally on the surface opposite to the surface of the chip substrate side; a chip substrate holding portion for holding a chip substrate; An ultraviolet light source for irradiating the adhesive layer with ultraviolet rays, a photomask holding portion for holding a photomask having a shielding portion for shielding ultraviolet rays and a transmitting portion for transmitting ultraviolet rays, a holding member holding portion for holding the holding member, a camera for observing the chip substrate holding portion, the photomask holding portion, the holding member held by the holding member holding portion, the chip substrate and the photomask; the chip substrate holding portion; the ultraviolet light source; A holding section, a holding member holding section, and a control section for controlling the camera, wherein the chip substrate holding section, the photomask holding section, and the holding member holding section can move independently of each other. The controller positions the holding member and the chip substrate using observation results of the holding member and the chip substrate by the camera, and uses observation of the chip substrate and the photomask by the camera. to position the chip substrate and the photomask.

In the method of manufacturing a light-emitting substrate for a transfer member according to the present invention, a plurality of the light-emitting diode chips are electrically connected to a circuit of a circuit board on the transfer member. A step of collectively transferring from the member to the circuit board is provided. The adhesiveness of the first adhesive layer of the holding member is reduced by heating, cooling, or ultraviolet irradiation, and the plurality of light emitting diode chips are collectively transferred from the holding member of the transfer member to the circuit board. the step of reducing the adhesiveness of the first adhesive layer of the holding member by heating, cooling, or ultraviolet irradiation; and peeling the light-emitting diode chip from the first adhesive layer. You can stay.

ADVANTAGE OF THE INVENTION According to this invention, the productivity of the light emitting board in which several light emitting diode chips are arrange|positioned can be improved.

1 is an exploded perspective view of a display device using a light emitting substrate with micro light emitting diode chips; FIG. 1 is a plan view of a light emitting substrate with micro light emitting diode chips; FIG. FIG. 3 is a plan view showing an enlarged part of the light emitting substrate, showing the A region of FIG. 2; FIG. 4 is an enlarged plan view showing the periphery of the micro light emitting diode chip on the light emitting substrate, showing the B region of FIG. 3; FIG. 4 is an enlarged longitudinal sectional view of a portion of a light emitting substrate having micro light emitting diode chips, showing the CC section of FIG. 3; It is a top view of a holding member. FIG. 7 is a plan view showing an enlarged part of the holding member, showing area D in FIG. 6 ; FIG. 8 is a longitudinal sectional view showing an enlarged part of the holding member, showing the EE cross section of FIG. 7; It is a top view which expands and shows a part of transfer member. FIG. 10 is a longitudinal sectional view showing an enlarged part of the transfer member, showing the FF section of FIG. 9; FIG. 4 is a vertical cross-sectional view showing a process of transferring micro light emitting diode chips from a transfer member to a circuit board; FIG. 3 is a plan view showing a chip substrate with diced micro light emitting diode chips; FIG. 13 is a longitudinal cross-sectional view showing a chip substrate with diced micro light-emitting diode chips, showing cross-section GG of FIG. 12; It is a top view which shows an example of a photomask. FIG. 10 is a plan view for explaining a process of holding the micro light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the first light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the first light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the first light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the first light emitting diode chip on the holding member; FIG. 4 is a plan view showing an enlarged first region R1 of the holding member after a step of holding the first light emitting diode chip in the first region R1 of the holding member; FIG. 4 is a plan view showing the chip substrate after undergoing a step of holding the first light emitting diode chip in the first region R1 of the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding a second light emitting diode chip on a holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding a second light emitting diode chip on a holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding a second light emitting diode chip on a holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the third light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the third light emitting diode chip on the holding member; FIG. 10 is a vertical cross-sectional view for explaining a step of holding the third light emitting diode chip on the holding member; 1 is a schematic diagram schematically showing an example of a transfer member manufacturing apparatus according to an embodiment; FIG. FIG. 4 is a vertical cross-sectional view for explaining a process of transferring the micro light-emitting diode chip from the transfer member to the circuit board; FIG. 4 is a vertical cross-sectional view for explaining a process of transferring the micro light-emitting diode chip from the transfer member to the circuit board; FIG. 4 is a vertical cross-sectional view for explaining a process of transferring the micro light-emitting diode chip from the transfer member to the circuit board; It is a figure for demonstrating the example of a changed completely type of a holding member.

An embodiment of the present invention will be described below with reference to the drawings. In the drawings attached to this specification, for the convenience of illustration and ease of understanding, the scale and the ratio of vertical and horizontal dimensions are changed and exaggerated from those of the real thing.

As used herein, the terms "plate", "sheet", and "film" are not to be distinguished from one another based solely on their designation. For example, "plate" is a concept that includes members that can be called "sheets" and "films." In addition, "plate surface (sheet surface, film surface)" refers to the target plate-shaped member (sheet-shaped member) when viewed from the whole and perspective. member, film-like member).

Furthermore, the terms used herein to specify shapes and geometric conditions and their degrees, such as "parallel", "perpendicular", "identical", length and angle values, etc., are not strictly defined. It shall be interpreted to include the extent to which similar functions can be expected without being bound by the meaning.

FIG. 1 is an exploded perspective view schematically showing a display device 1 using a light emitting substrate 10 having micro light emitting diode chips 50. As shown in FIG. The display device 1 displays an image or the like on the display surface 5 . In the example shown in FIG. 1 , the display device 1 has a light emitting substrate 10 and a diffusion layer 7 arranged to face the light emitting substrate 10 . The surface of the diffusion layer 7 opposite to the side facing the light emitting substrate 10 is the display surface 5 of the display device 1 . The display device 1 is a so-called micro LED display that uses light emitted from one or more light emitting diodes as one pixel. In the illustrated example, the light emitted by the light emitting substrate 10 is diffused by the diffusion layer 7 . However, the diffusion layer 7 can be omitted.

FIG. 2 is a plan view of the light emitting substrate 10 with the micro light emitting diode chip 50. FIG. FIG. 3 is a plan view showing an enlarged part of the light emitting substrate 10, showing the area A in FIG. FIG. 4 is an enlarged plan view showing the periphery of the micro light-emitting diode chip 50 of the light-emitting substrate 10, showing the B region of FIG. FIG. 5 is an enlarged longitudinal sectional view showing a portion of the light emitting substrate 10 having the micro light emitting diode chip 50, showing the CC section of FIG.

The light emitting substrate 10 emits light forming an image displayed on the display surface 5 . As shown in FIGS. 2 and 3, the light emitting substrate 10 includes a circuit board 11 and a plurality of micro light emitting diode chips (also simply referred to as "light emitting diode chips") 50 regularly arranged two-dimensionally on the circuit board 11. and have The circuit board 11 has positioning means for positioning the transfer member 20 having the micro light emitting diode chips 50 in the step of transferring the micro light emitting diode chips 50 from the transfer member 20 to be described later. In the example shown in FIGS. 2 and 3, the positioning means are a plurality of cross-shaped positioning marks M1. However, the cross-shaped positioning mark M1 is merely an example, and various positioning marks M1 such as a square, a triangle, and a circle can be used. Moreover, as shown in FIG. 4, the circuit board 11 has a circuit 13 . Furthermore, each micro light emitting diode chip 50 has two electrodes 51, as shown in FIG. Micro light emitting diode chip 50 is electrically connected to circuit 13 through electrode 51 . By controlling the current flowing through the circuit 13 and applying a voltage between the two electrodes 51, any micro light emitting diode chip 50 can be caused to emit light. The combination of light emitted by the micro light emitting diode chips 50 can form an image displayed by the display device 1 .

The wavelength of the light emitted from the micro light emitting diode chip 50 is determined by the semiconductor material or the like that constitutes the micro light emitting diode chip 50 . The micro light emitting diode chip 50 includes, for example, a GaAs-based compound semiconductor, an InP-based compound semiconductor, a GaN-based compound semiconductor, or the like. The dimensions of the micro light emitting diode chip 50 in plan view can be, for example, a rectangular shape with a side of 3 μm or more and 1000 μm or less, and the thickness of the micro light emitting diode chip 50 can be, for example, 10 μm or more and 500 μm or less.

In the illustrated example, the micro light emitting diode chip 50 includes a first light emitting diode chip 50R that emits red light with a wavelength range of 620 nm to 680 nm, and a second light emitting diode chip that emits green light with a wavelength range of 530 nm to 570 nm. 50G, and a third light emitting diode chip 50B that emits blue light with a wavelength range of 440 nm to 480 nm. The first light-emitting diode chip 50R, the second light-emitting diode chip 50G, and the third light-emitting diode chip 50B arranged near each other form one pixel of the display device 1. FIG. Therefore, the light emitting substrate 10 can emit light for forming an image displayed in full color.

The light emitting substrate 10 is manufactured by placing the micro light emitting diode chips 50 on the circuit board 11 where the circuit 13 is formed. In order to manufacture the light emitting substrate 10 on which the plurality of micro light emitting diode chips 50 are arranged with high productivity, a holding member 30 and a transfer member 20 having the holding member 30 as shown in FIGS.

The holding member 30 of the present embodiment and the transfer member 20 having the holding member will be described below with reference to FIGS. 6 to 11. FIG.

6 is a plan view of the holding member 30. FIG. FIG. 7 is an enlarged plan view showing a part of the holding member 30, showing the D area in FIG. FIG. 8 is a longitudinal sectional view showing an enlarged part of the holding member 30, showing the EE cross section of FIG.

The holding member 30 is a member capable of holding a plurality of micro light emitting diode chips 50 . As shown in FIGS. 6 , 7 and 8 , the holding member 30 has a base material 31 and a plurality of projecting holding parts 32 provided on one surface of the base material 31 . The projecting holding portion 32 has a projecting structure 33 that is the main body of the projecting holding portion 32 and an adhesive layer 35 provided at the tip of the projecting structure 33 .

The base material 31 is a plate-like member that appropriately supports the plurality of projecting holding portions 32 . The base material 31 has positioning means used for positioning the chip substrate 40 having the micro light emitting diode chip 50 and the holding member 30 in the step of holding the micro light emitting diode chip 50 on the holding member 30 to be described later. In the example shown in FIGS. 6 and 7, the positioning means are cross-shaped positioning marks M2. However, the cross-shaped positioning mark M2 is merely an example, and various positioning marks M2 such as a square, triangle, and circle can be used. As shown in FIG. 6, a plurality of positioning marks M2 are provided on one surface of the base material 31 for each region that partitions the holding member 30 at regular intervals. Moreover, in order to facilitate observation of the positioning mark M2, the substrate 31 is preferably transparent.

In addition, the term “transparent” means having transparency to the extent that one side of the base material can be seen through the other side through the base material, for example, 30% or more, more Preferably, it means having a visible light transmittance of 70% or more. The visible light transmittance is the transmittance at each wavelength when measured within the measurement wavelength range of 380 nm to 780 nm using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, compliant with JIS K 0115). is specified as the mean of

The area of the base material 31 in plan view is larger than that of the chip substrate 40 having a plurality of micro light-emitting diode chips 50, which will be described later. Specifically, it is preferable that the area of the substrate 31 in plan view is 176 cm ² or more. Moreover, it is preferable that the dimension of the base material 31 in plan view is equal to or larger than the dimension of the circuit board 11 in plan view so that the dimension of the transfer member 20 in plan view is equal to or larger than the dimension in plan view of the circuit board 11 .

The thickness of the base material 31 is preferably 0.5 mm or more and 3 mm or less in consideration of transparency, appropriate supportability of the projecting structures 33, and the like. Further, in order to prevent deformation of the base material 31 in the manufacturing process of the light emitting substrate 10, which will be described later, it is preferable that the base material 31 has high rigidity. Moreover, it is preferable that the base material 31 is not easily deformed by heat. Specifically, the coefficient of linear expansion of the base material 31 is preferably 10×10 ⁻⁵ /K or less, more preferably 5×10 ⁻⁵ /K or less. Examples of materials for the base material 31 include acrylic resin and glass.

The protrusion holding portion 32 is a portion that holds the micro light emitting diode chip 50 . The projecting holding part 32 is provided at a position where the holding member 30 holds the micro light emitting diode chip 50 on the base material 31 . That is, the projecting holding portion 32 is provided at a position corresponding to the position on the circuit board 11 where the micro light emitting diode chip 50 is arranged. It is preferable that the dimension of the protrusion holding portion 32 in plan view is equal to or smaller than the dimension of the micro light emitting diode chip 50 . In the illustrated example, the dimension of the projection holding portion 32 in plan view is equal to the dimension of the micro light emitting diode chip 50 .

The projecting holding portions 32 are regularly arranged two-dimensionally on one surface of the base material 31 . The regular two-dimensional arrangement of the protrusion holders 32 corresponds to a plurality of micro light-emitting diode chips 50 regularly arranged two-dimensionally on the circuit board 11 . In other words, the arrangement interval and arrangement pattern of the protrusion holding portions 32 are the same as the arrangement interval and arrangement pattern of the plurality of micro LED chips 50 to be arranged on the circuit board 11 . The projecting holding portions 32 are arranged at a pitch pa1 in the first direction d1, and arranged at a pitch pa2 in a second direction d2 non-parallel to the first direction d1. In the illustrated example, the first direction d1 and the second direction d2 are orthogonal to each other. The pitches pa1 and pa2 are, for example, 50 μm or more and 870 μm or less.

A projecting structure 33 , which is the main body of the projecting holding portion 32 , protrudes in the direction normal to the plate surface of the base material 31 . The protruding structure 33 has a length and flexibility at least to the extent that the protruding holding part 32 can be elastically compressed and deformed by at least the thickness of the micro light emitting diode chip 50 for the manufacturing method of the transfer member 20 to be described later. have. From this point of view, the length by which the projecting structure 33 protrudes from the base material 31 is preferably 5 μm or more and 500 μm or less, and more preferably 50 μm or more and 200 μm or less. Also, the Young's modulus of the projecting structure 33 is preferably 10 GPa or less, more preferably 5 GPa or less. Such protruding structures 33 are made of acrylic resin, for example, and can be formed using a photolithographic technique or an imprint technique.

The adhesive layer 35 is provided at the tip of the protruding structure 33 so that the micro light emitting diode chip 50 can be held by the protruding holding portion 32 . The adhesive layer 35 has adhesiveness. The adhesiveness of the adhesive layer 35 can be reduced, for example, by heating, cooling, or UV irradiation. In addition, in this specification, stickiness is a sticky property, and is not distinguished from adhesiveness. As the material of the adhesive layer 35, for example, an acrylic adhesive is used. The thickness of the adhesive layer 35 is, for example, 0.1 μm or more and 100 μm or less.

FIG. 9 is a plan view showing an enlarged part of the transfer member 20. As shown in FIG. FIG. 10 is a longitudinal cross-sectional view showing an enlarged part of the transfer member 20, showing the FF cross section of FIG.

The transfer member 20 has a holding member 30 and a plurality of micro light emitting diode chips 50 held by the holding member 30 . The plurality of micro light emitting diode chips 50 are arranged on the transfer member 20 so as to be held at positions corresponding to positions on the circuit board 11 to which the micro light emitting diode chips 50 are to be transferred. ing. In other words, the arrangement interval and arrangement pattern of the plurality of micro light emitting diode chips 50 on the transfer member 20 are the same as the arrangement interval and arrangement pattern in which the plurality of micro light emitting diode chips 50 are to be arranged on the circuit board 11. there is
In the illustrated example, the holding member 30 holds a first light emitting diode chip 50 R, a second light emitting diode chip 50 G, and a third light emitting diode chip 50 B as the micro light emitting diode chips 50 .

FIG. 11 is a longitudinal sectional view showing the process of transferring the micro light emitting diode chip 50 from the transfer member 20 to the circuit board 11. As shown in FIG. The transfer member 20 is configured to transfer a plurality of micro light-emitting diode chips 50 collectively onto the circuit 13 of the circuit board 11 . It is preferable that the dimension of the transfer member 20 in plan view is equal to or larger than the dimension of the circuit board 11 in plan view so that the micro light-emitting diode chips 50 can be arranged on the entire circuit board 11 with only one transfer.

Next, a method for holding the micro light-emitting diode chip 50 on the holding member 30, that is, a method for manufacturing the transfer member 20 will be described with reference to FIGS. 12 to 20. FIG.

FIG. 12 is a plan view showing a chip substrate 40 with diced micro light emitting diode chips 50 . FIG. 13 is a longitudinal sectional view showing the chip substrate 40 with the diced micro light emitting diode chips 50, showing the GG section of FIG.

First, as shown in FIGS. 12 and 13, a chip substrate 40 having a plurality of micro light emitting diode chips 50 diced on one surface is prepared. This chip substrate 40 is prepared for each of the first light emitting diode chip 50R, the second light emitting diode chip 50G and the third light emitting diode chip 50B. That is, three types of chip substrates 40 are prepared: the chip substrate 40 having the first light emitting diode chip 50R, the chip substrate 40 having the second light emitting diode chip 50G, and the chip substrate having the third light emitting diode chip 50B. be.

In the illustrated example, the chip substrate 40 is configured as a substrate obtained by temporarily transferring the micro light emitting diode chips 50 from a diced wafer. The chip substrate 40 has a chip substrate 41 , an adhesive layer 42 laminated on the chip substrate 41 , and a plurality of micro LED chips 50 arranged on the adhesive layer 42 .

The chip base material 41 is a plate-like member that holds the micro light emitting diode chip via the adhesive layer 42 . The chip substrate 41 has positioning means for positioning with the holding member 30 . In the example shown in FIG. 12, the positioning means are a plurality of cross-shaped positioning marks M3. However, the cross-shaped positioning mark M3 is merely an example, and various positioning marks M3 such as a square, triangle, and circle can be used.

The material of the chip substrate 41 is not limited, and wafer glass or acrylic, for example, is used. However, as will be described later, when the adhesive layer 42 of the chip substrate 40 is one whose adhesiveness is reduced by ultraviolet irradiation, it is preferable that the chip base material 41 be transparent and transmit ultraviolet rays. . Although the area of the base material 31 in a plan view is not particularly limited, for example, about 10 to 800 cm ² can be considered. The thickness of the chip base material 41 is preferably 0.1 mm or more and 5 mm or less in consideration of transparency, ultraviolet transmittance, proper holding of the micro light emitting diode chip 50, and the like.

The adhesive layer 42 of the chip substrate 40 has adhesiveness, and has a property that the adhesiveness is reduced by irradiation with ultraviolet rays. More specifically, the adhesive layer 42 of the chip substrate 40 has higher adhesiveness than the adhesive layer 35 of the protruding structure 33 of the holding member 30, and the adhesive layer 42 of the holding member 30 is increased by irradiating ultraviolet rays. It will have less stickiness than layer 35 . By irradiating ultraviolet rays from the back surface of the chip substrate 40 through the photomask 60, the adhesiveness of specific regions of the adhesive layer 42 can be selectively reduced. In this case, the chip base material 41 needs to transmit ultraviolet rays.

FIG. 14 is a plan view showing an example of such a photomask 60. As shown in FIG. The photomask 60 has a shielding portion 60a that shields ultraviolet rays and a transmission portion 60b that transmits ultraviolet rays. The photomask 60 also has positioning means for positioning with the chip substrate 40 . In the example shown in FIG. 14, the positioning means are a plurality of cross-shaped positioning marks M4. However, the cross-shaped positioning mark M4 is merely an example, and various positioning marks M3 such as a square, triangle, and circle can be used.

In addition, transmitting ultraviolet rays means having an ultraviolet transmittance of, for example, 30% or more, more preferably 70% or more. Ultraviolet transmittance is the transmittance at each wavelength when measured using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, JIS K 0115 compliant product) within a measurement wavelength range of 10 nm to 500 nm. Specified as mean.

As the material of the adhesive layer 42 of the chip substrate 40, for example, an adhesive material whose adhesiveness is lowered by ultraviolet rays is used. The thickness of the adhesive layer 42 of the chip substrate 40 is, for example, 0.1 μm or more and 100 μm or less.

Each micro light emitting diode chip 50 has two electrodes 51 provided on the side of the chip substrate 41 . The micro light emitting diode chips 50 are arranged on the chip substrate 41 at a pitch pb1 in the first direction d1, and arranged at a pitch pb2 in a second direction d2 non-parallel to the first direction d1. That is, the micro light emitting diode chips 50 are formed by dicing the wafer in the first direction d1 and the second direction d2. In the illustrated example, the first direction d1 and the second direction d2 are orthogonal to each other. The pitches pb1 and pb2 are, for example, 5 μm or more and 200 μm or less.

Here, an integer multiple (three times in the illustrated example) of the array pitch pb1 of the micro light emitting diode chips 50 of the chip substrate 40 in the first direction d1 is the first pitch of the plurality of projecting holding portions 32 of the holding member 30. The arrangement pitch in the direction d1 is pa1. Similarly, an integer multiple (three times in the illustrated example) of the array pitch pb2 in the second direction d2 of the micro light emitting diode chips 50 of the chip substrate 40 is the second pitch of the plurality of projecting holding portions 32 of the holding member 30. The arrangement pitch is pa2 in the direction d2. Since the arrangement interval and arrangement pattern of the projecting holding portions 32 of the holding member 30 are the same as the arrangement interval and arrangement pattern of the plurality of micro light emitting diode chips 50 arranged on the circuit board 11, the micro light emission of the chip substrate 40 is achieved. An integral multiple of the array pitch pb1 of the diode chips 50 in the first direction d1 is the array pitch of the micro light emitting diode chips 50 (first light emitting diode chips 50R) on the circuit board 11 in the first direction d1, An integral multiple of the array pitch pb2 in the second direction d2 is the array pitch of the micro light emitting diode chips 50 (first light emitting diode chips 50R) on the circuit board 11 in the second direction d2.

FIG. 15 is a plan view for explaining the process of holding the micro light emitting diode chip on the holding member 30. FIG.

The holding member 30 has a plurality of regions arranged in the first direction d1 and the second direction d2. The shape and area of each region are approximately the same as the shape and area of the region on the chip substrate 40 where the micro light emitting diode chips 50 are arranged. In the illustrated example, the holding member has fifteen regions, a first region R1 to a fifteenth region R15.

The step of holding the micro light emitting diode chips on the holding member 30 includes the step of holding the first light emitting diode chip 50R on the holding member 30, followed by the step of holding the second light emitting diode chip 50G on the holding member 30, and Next, a step of holding the third light emitting diode chip 50B on the holding member 30 is provided.

The step of holding the first light emitting diode chip 50R on the holding member 30 is the step of bringing the chip substrate 40 (first chip substrate) having the first light emitting diode chip 50R into contact with the first region R1 of the holding member 40 (first step). ), and a projecting holding portion 32 for holding the first light emitting diode chip 50R (hereinafter also referred to as “first projecting holding portion 32R”) in the adhesive layer 42 of the chip substrate 40 (first chip substrate). ) in which the adhesiveness of the region where the first light emitting diode chip 50R is arranged is made lower than the adhesiveness of the adhesive layer 35 of the holding member 30 by ultraviolet irradiation (second step); 40 (first chip substrate) is separated from the holding member 30 to hold the first light emitting diode chip 50R on the projecting holding portion 32 (third step); to move the holding member 30 relatively to bring the chip substrate 40 (first chip substrate) into contact with the second region R2 of the holding member 30, and then repeating the same steps as the steps in the first region R1. and have

After the step of holding the first light emitting diode chip 50R on the holding member 30, the step of holding the second light emitting diode chip 50G on the holding member 30 is performed. The step of holding the second light emitting diode chip 50G on the holding member 30 is the step of bringing the chip substrate 40 (second chip substrate) having the second light emitting diode chip 50G into contact with the first region R1 of the holding member 40 (fourth step). ), and a projecting holding portion 32 for holding the second light-emitting diode chip 50G in the adhesive layer 42 of the chip substrate 40 (second chip substrate) (hereinafter also referred to as “second projecting holding portion 32G”). ) in which the adhesiveness of the region where the second light emitting diode chip 50G is arranged is made lower than the adhesiveness of the adhesive layer 35 of the holding member 30 by ultraviolet irradiation (fifth step); 40 (second chip substrate) is separated from the holding member 30 to hold the second light emitting diode chip 50G on the projecting holding portion 32 (sixth step); to move the holding member 30 relatively to bring the chip substrate 40 (second chip substrate) into contact with the second region R2 of the holding member 30, and then repeating the same steps as the steps in the first region R1. and have

After the step of holding the second light emitting diode chip 50G on the holding member 30, the step of holding the third light emitting diode chip 50B on the holding member 30 is performed. In the step of holding the third light emitting diode chip 50B on the holding member 30, the step of bringing the chip substrate 40 having the third light emitting diode chip 50B into contact with the first region R1 of the holding member 40, and the step of contacting the adhesive layer 42 of the chip substrate 40 of the region where the third light-emitting diode chip 50B is arranged and contacts the projecting holding portion 32 for holding the third light-emitting diode chip 50B (hereinafter sometimes referred to as "third projecting holding portion 32B") a step of making the adhesiveness lower than that of the adhesive layer 35 of the holding member 30 by irradiating ultraviolet rays; The step of holding, the step of moving the holding member 30 relative to the chip substrate 40 to bring the chip substrate 40 into contact with the second region R2 of the holding member 30, and the subsequent step in the first region R1. and repeating the steps of

First, the process of holding the first light emitting diode chip 50R on the holding member 30 will be described in more detail.

16A to 16D are longitudinal sectional views for explaining the process of holding the first light emitting diode chip 50R on the holding member 30. FIG.

First, as shown in FIG. 16A, the surface of the chip substrate 40 on which the micro light-emitting diode chips 50 are arranged and the first region R1 on the surface of the holding member 30 on which the projecting holding portions 32 are arranged are separated. face it. After that, the chip substrate 40 and the holding member 30 are positioned. Positioning is performed based on the positioning means of the base material 31 of the holding member 30 and the positioning means of the chip substrate 40 . As a specific example, as shown in FIG. 15, positioning is performed by aligning the positioning mark M2 of the base material 31 with the positioning mark M3 of the chip substrate 40 in the first region R1 of the holding member 30. will be Whether the positioning marks M2 and M3 match can be confirmed, for example, by a camera 80 arranged on the opposite side of the surface of the holding member 30 on which the projecting holding portions 32 are arranged. Since the base material 31 is transparent, it is possible to check the positioning marks M2 and M3 through the base material 31 from the side opposite to the surface on which the projecting holding portions 32 of the holding member 30 are arranged.

The chip substrate 40 and the holding member 30 may be positioned by only one of the positioning means of the base material 31 of the holding member 30 and the positioning means of the chip substrate 40 . Further, the chip substrate 40 and the holding member 30 may be positioned only by observing the chip substrate 40 and the holding member 40 with the camera 80 without using the positioning marks M2 and M3.

Next, as shown in FIG. 16B, the chip substrate 40 and the holding member 30 are brought closer together, and the chip substrate 40 is brought into contact with the holding member 30 with a predetermined contact pressure. When the chip substrate 40 contacts the holding member 30 , the first light emitting diode chips 50</b>R of the chip substrate 40 come into contact with the adhesive layer 35 at the tips of the plurality of projecting holding portions 32 in the first region R<b>1 of the holding member 30 . At this time, the first light emitting diode chip 50R contacts the first projecting holding portion 32R, and the first light emitting diode chip 50R also contacts the second projecting holding portion 32G and the third projecting holding portion 32B.

Here, since the protruding structure 33 which is the main body of the protruding holding part 32 has flexibility, specifically, the Young's modulus of the protruding structure 33 is 10 GPa or less, more preferably 5 GPa or less. When the substrate 40 contacts the holding member 30 , the projecting holding portion 32 of the holding member 30 can deform in a direction perpendicular to the contact surface between the chip substrate 40 and the projecting holding portion 32 . Therefore, the contact pressure for bringing the chip substrate 40 into contact with the projecting holding portion 32 is uniformly applied to each projecting holding portion 32 that is in contact with the chip substrate 40 . In other words, a part of the protrusion holding part 32 can be prevented from contacting the micro LED chip 50 of the chip substrate 40 with high contact pressure. When a part of the protrusion holding part 32 contacts the micro LED chip 50 with a high contact pressure, the stickiness between the protrusion holding part 32 and the micro LED chip 50 will cause the other protrusion holding part 32 and the other micro LED chip to stick together. The adhesiveness with the chip 50 may be different, resulting in handling difficulties of the manufactured transfer member 20, or the micro light emitting diode chip 50 may be destroyed due to high contact pressure. For this reason, it is preferable to avoid a portion of the projecting holding portion 32 from contacting the micro light emitting diode chip 50 with a high contact pressure.

Next, by irradiating ultraviolet rays from the rear surface of the chip substrate 40 through a photomask 60 as shown in FIG. It selectively reduces the tackiness of the tacky layer 42 in the areas where the tackiness is applied. As a result, the adhesive layer 42 in that region of the chip substrate 40 has lower adhesiveness than the adhesive layer 35 of the holding member 30 . On the other hand, the adhesive layer 42 in the region of the chip substrate 40 where the first light emitting diode chip 50R that contacts the second projecting holding portion 32G or the third projecting holding portion 32B is arranged is thicker than the adhesive layer 35 of the holding member 30. Remains highly tacky.

It should be noted that this ultraviolet irradiation may be performed before the chip substrate 40 contacts the holding member 30, or from before the chip substrate 40 contacts the holding member 30 to after the chip substrate 40 contacts the holding member 30. May be done continuously.

Further, the photomask 60 and the chip substrate 40 are positioned before the irradiation of the ultraviolet rays. and positioning means. As a specific example, the positioning is performed by aligning the positioning mark M4 of the photomask 60 with the positioning mark M3 of the chip substrate 41 of the chip substrate 40 . At this time, if the chip substrate 41 of the chip substrate 40 is transparent, the camera 80 used for positioning the holding member 30 and the chip substrate 40 can also be used for positioning the photomask 60 and the chip substrate 40 . can. Therefore, the chip base material 41 of the chip substrate 40 is preferably transparent. If the chip substrate 41 is not transparent, a positioning mark (not shown) is also provided on the back side of the chip substrate 40 (that is, the side opposite to the adhesive layer 42 side), and this positioning means and the photomask have The photomask 60 and the chip substrate 40 can be positioned based on the positioning marks M4. Further, the photomask 60 and the chip substrate 40 may be positioned only by observing the photomask 60 and the chip substrate 40 with the camera 80 without using the positioning marks M2 and M3.

Next, as shown in FIG. 16C, the chip substrate 40 and the holding member 30 are separated. At this time, the adhesive layer 42 in the region of the chip substrate 40 where the first light emitting diode chip 50R in contact with the first projecting holding portion 32R is arranged has lower adhesiveness than the adhesive layer 35 of the holding member 30. Therefore, the first light emitting diode chip 50R remains attached to the adhesive layer 35 of the first projecting holding portion 32R. On the other hand, the adhesive layer 42 in the region of the chip substrate 40 where the first light emitting diode chip 50R in contact with the second protruding holding portion 32G or the third protruding holding portion 32B is disposed is the adhesive layer 35 of the holding member 30. Therefore, the first light emitting diode chip 50R is peeled off from the adhesive layer 35 of the second protrusion holding portion 32G or the third protrusion holding portion 32B.

By adhering the first light emitting diode chip 50 to the adhesive layer 35 of the first protrusion holding part 32</b>R in this manner, the plurality of protrusion holding parts 32 hold the first light emitting diode chip 50 . That is, the first light emitting diode chip 50R is held from the chip substrate 40 on the plurality of first projecting holding portions 32R within the first region R1 of the holding member 30. As shown in FIG.

Next, as shown in FIGS. 16D and 15, the holding member 30 is moved relative to the chip substrate 40 so that the surface of the chip substrate 41 of the chip substrate 40 on which the micro light-emitting diode chips 50 are arranged. , and the second region R2 of the surface on which the projecting holding portions 32 of the base member 31 of the holding member 30 are arranged. After that, by repeating the same steps as the steps in the first region R1, the first light emitting diode chips 50R are held on the plurality of first projecting holding portions 32R in the second region R2. Furthermore, after that, the same process as the process in the first region R1 is repeated for all the regions (the third region R3 to the fifteenth region R15) of the holding member 30, and the first light emission is performed on the plurality of first projecting holding portions 32R. The diode chip 50R is held.

17 is a plan view showing an enlarged region R1 of the holding member 30 after the step of holding the first light emitting diode chip 50R in the first region R1 of the holding member 30. FIG.

As shown in FIG. 17, in the holding member 30 after undergoing the step of holding the first light emitting diode chip 50R in the first region R1 of the holding member 30, the first light emitting diode chip 50R is placed only on the first projecting holding portion 32R. 50R is held, and the first light emitting diode chip 50R is not held by the second projecting holding portion 32G or the third projecting holding portion 32B.

The chip substrate 40 and the holding member 30 are positioned, and the dimensions of the projecting holding portion 32 in plan view are equal to the dimensions of the first light emitting diode chip 50R. One micro light emitting diode chip 50 can be held by one of the projecting holding portions 32 for holding the light emitting diode chip 50R.

Further, as described above, the arrangement pitch pa1 of the projecting holding portions 32 of the holding member 30 in the first direction d1 is an integral multiple (illustrated 3 times in the example shown), therefore, the pitch of the arrangement of the first projecting holding portions 32R of the holding member 30 in the first direction d1 is the same as that of the first light emitting diode chips 50R of the chip substrate 40 in the first direction d1. Since it is an integral multiple (nine times in the illustrated example) of the array pitch pb1, one first light emission is generated for all of the first projecting holding portions 32R in the first region R1 in the first direction d1. Diode chip 50R can be held.

Similarly, the arrangement pitch pa2 of the plurality of projecting holding portions 32 of the holding member 30 in the second direction d2 is an integer multiple (not shown) of the arrangement pitch pb2 of the first light emitting diode chips 50R of the chip substrate 40 in the second direction d2. 3 times in the example), the pitch of the arrangement of the first projecting holding portions 32R of the holding member 30 in the second direction d2 is the same as the arrangement pitch of the first light emitting diode chips 50R of the chip substrate 40 in the second direction d2. is an integer multiple (nine times in the illustrated example) of the pitch pb2, one micro light emitting diode chip for each of all the first projecting holding portions 32R in the first region R1 in the second direction d2 50 can be held.

18 is a plan view showing the chip substrate 40 after the step of holding the first light emitting diode chip 50R in the first region R1 of the holding member 30. FIG.

As shown in FIG. 18, the chip substrate 40 after undergoing the step of holding the first light emitting diode chip 50R in the first region R1 of the holding member 30 is held by the holding member 30 through this step. A state is created in which there is an empty area 45 where the first light emitting diode chip 50R is removed. The layout pattern of the empty areas 45 of the chip substrate 40 corresponds to the layout pattern of the transparent portions 60b of the photomask 60 shown in FIG.

The first light emitting diode chip 50R, which contacts the adhesive layer 35 of the protruding holding portion 32 in the second region R2 following the first region R1 of the holding member 30, is attached to the adhesive layer 35 of the protruding holding portion 32 in the first region R1. It is different from the retained first light emitting diode chip 50R. The chip substrate 40 and the holding member 30 are positioned, the dimension of the projecting holding part 32 in plan view is equal to the dimension of the first light emitting diode chip 50R, and the projecting holding part 32 of the holding member 30 pitches pa1 and pa2 of the arrangement of the first light emitting diode chips 50R on the chip substrate 40 are integral multiples of the pitches pb1 and pb2 of the arrangement of the first light emitting diode chips 50R. Each of the holding portions 32 can hold one first light emitting diode chip 50R.

As described above, by repeating the step of relatively moving the holding member 30 with respect to the chip substrate 40 and the step of holding the micro light-emitting diode chip 50 on the projecting holding portion 32 in a certain area, the holding member 30 can be held in multiple positions. , the first light emitting diode chip 50R can be held in each of the first projecting holding portions 32R in the regions of . As shown in FIG. 15, by moving the holding member 30 relative to the chip substrate 40 in the first direction d1 and the second direction d2, the entire area of the holding member 30 is moved to the first projecting holding portion 32R. It can hold the first light emitting diode chip 50R.

Next, the process of holding the second light emitting diode chip 50G on the holding member 30 will be described.

19A, 19B, and 19C are longitudinal sectional views for explaining the process of holding the second light emitting diode chip 50G on the holding member 30. FIG.

The process of causing the holding member 30 to hold the second light emitting diode chip 50G is basically the same as the process of causing the holding member 30 to hold the first light emitting diode chip 50R. FIGS. 19A, 19B and 19C respectively correspond to FIGS. 16A, 16B and 16C relating to the step of holding the first light emitting diode chip 50R on the holding member 30. FIG. However, in the step of holding the second light emitting diode chip 50G on the holding member 30, as shown in FIG. This is different from the step of holding the first light emitting diode chip 50R on the holding member 30 in that respect.

Therefore, as shown in FIG. 19B , when the chip substrate 40 and the holding member 30 are brought close to each other and the chip substrate 40 is brought into contact with the holding member 30 , the second protrusion positioned on the first projecting holding portion 32R of the holding member 30 is moved. The light emitting diode chip 50G comes into contact with the first light emitting diode chip 50R held by the first projecting holding portion 32R. At this time, the first projecting holding portion 32R is compressed more than the second projecting holding portion 32G or the third projecting holding portion 32B by the thickness of the first light emitting diode chip 50R. Therefore, the first projecting holding portion 32R can be compressed and deformed by at least the thickness of the first light emitting diode chip 50R.

Next, the process of holding the third light emitting diode chip 50B on the holding member 30 will be described.

20A, 20B and 20C are longitudinal sectional views for explaining the process of holding the third light emitting diode chip 50B on the holding member 30. FIG.

The process of holding the third light-emitting diode chip 50B on the holding member 30 is basically the same as the process of holding the first light-emitting diode chip 50R on the holding member 30 . FIGS. 20A, 20B and 20C respectively correspond to FIGS. 16A, 16B and 16C relating to the step of holding the first light emitting diode chip 50R on the holding member 30. FIG. However, in the step of holding the third light emitting diode chip 50B on the holding member 30, as shown in FIG. This step is different from the step of holding the first light emitting diode chip 50R in the holding member 30 in that the second light emitting diode chip 50G is held by the second projecting holding portion 32G.

Therefore, as shown in FIG. 20B, when the chip substrate 40 and the holding member 30 are brought close to each other and the chip substrate 40 is brought into contact with the holding member 30, the first projecting holding portion 32R or the second projecting holding portion 32R of the holding member 30 The third light emitting diode chip 50G positioned above 32G comes into contact with the first light emitting diode chip 50R or the second light emitting diode chip 50G held by the first projecting holding portion 32R or the second projecting holding portion 32G. . At this time, the first projecting holding portion 32R or the second projecting holding portion 32G is compressed more than the third projecting holding portion 32B by the thickness of the first light emitting diode chip 50R or the second light emitting diode chip 50G. It will be. Therefore, the second projecting holding portion 32G can be compressed and deformed by at least the thickness of the second light emitting diode chip 50G.

Through the above steps, the transfer member 20 having the holding member 30 and the plurality of first light emitting diode chips 50R, second light emitting diode chips 50G and third light emitting diode chips 50B as shown in FIGS. manufactured.

FIG. 21 is a schematic diagram schematically showing an example of a manufacturing apparatus 90 for the transfer member 20 of this embodiment.

The transfer member 20 manufacturing apparatus 90 of the present embodiment includes, for example, a control unit 91, a holding member holding unit 92 holding the holding member 20, a chip substrate holding unit 93 holding the chip substrate 40, and a photomask 60. It has a photomask holding portion 94 to hold, an ultraviolet light source 95 and a camera 80 .

The holding member holding portion 92, the chip substrate holding portion 93, and the photomask holding portion 94 hold the holding member 30, the chip substrate 40, or the photomask 60 so that their plate surfaces are parallel to the first direction d1 and the second direction d2. In addition, they are configured to be able to move independently in the first direction d1, the second direction d2, and the third direction d3. The ultraviolet light source 95 is a light source of ultraviolet light that irradiates the adhesive layer 42 of the chip substrate 40, and is configured to be movable in the first direction d1 and the second direction d2. In order to position the holding member 20 , the chip substrate 40 and the photomask 60 , the camera 80 moves the holding member 30 , the chip substrate 40 and the holding member 30 held by the chip substrate holding portion 93 , the photomask holding portion 94 and the holding member holding portion 92 . A camera for observing the photomask 60 or its positioning marks M2 to M4, and is configured to be movable in a first direction d1 and a second direction d2.

The control unit 91 controls the holding member holding unit 92, the chip substrate holding unit 93, the photomask holding unit 94, the ultraviolet light source 95, and the camera 80 so as to perform the respective steps in the manufacturing method of the transfer member 20 of the present embodiment. to control. Further, the control unit 91 positions the holding member 30 and the chip substrate 40 using the observation result of the holding member 30 and the chip substrate 40 by the camera 80, and the observation result of the chip substrate 40 and the photomask 60 by the camera 80. is used to position the chip substrate 40 and the photomask 60 .

With the transfer member manufacturing apparatus described above, the productivity of the transfer member can be improved.

Next, a method of arranging the micro light emitting diode chips 50 on the circuit board 11 using the transfer member 20, that is, a method of manufacturing the light emitting board 10 will be described with reference to FIGS. 22A, 22B and 22C.

22A, 22B and 22C are longitudinal sectional views for explaining the process of transferring the micro light emitting diode chips 50 from the transfer member 20 to the circuit board 11. FIG.

First, as shown in FIG. 22A, the surface of the circuit board 11 on which the circuit 13 is formed faces the surface of the transfer member 20 on which the micro light emitting diode chips 50 are held. After that, the circuit board 11 and the transfer member 20 are positioned. Positioning is performed based on, for example, positioning means of the circuit board 11 and positioning means of the transfer member 20 . As a specific example, the positioning is performed by aligning the positioning mark M1 of the circuit board 11 with the positioning mark M2 of the substrate 31 of the transfer member 20 . It is possible to confirm that the positioning marks M1 and M2 match with a camera 80 arranged on the opposite side of the surface of the transfer member 20 on which the micro light-emitting diode chips 50 are held. Since the base material 31 is transparent, the positioning marks M1 and M2 can be confirmed through the base material 31 from the side opposite to the surface of the transfer member 20 on which the micro light emitting diode chips 50 are held.

The positioning mark M2 of the base material 31 used for positioning the circuit board 11 and the transfer member 20 may be the same as the positioning mark used for positioning the chip board 40 and the holding member 30. A positioning mark different from the positioning mark used for positioning the chip substrate 40 and the holding member 30 may be used.

Next, as shown in FIG. 22B, the transfer member 20 is pressed against the circuit board 11 . Since the circuit board 11 and the transfer member 20 are positioned, the micro light emitting diode chip 50 is pressed against the position where the circuit 13 of the circuit board 11 is provided, and the micro light emitting diode chip 50 is attached to the circuit 13 of the circuit board 11. can be electrically connected. An anisotropic conductive adhesive layer (not shown) for bonding the micro light emitting diode chip 50 to the circuit board 11 is formed at the position of the circuit board 11 where the micro light emitting diode chip 50 is arranged.

Here, since the protruding structure 33 which is the main body of the protruding holding portion 32 has flexibility, specifically, the Young's modulus of the protruding structure 33 is 10 GPa or less, more preferably 5 GPa or less. When the member 20 is pressed against the circuit board 11 , the projecting holding portion 32 of the holding member 30 can be deformed in a direction perpendicular to the pressing surface between the circuit board 11 and the projecting holding portion 32 . Therefore, the pressure that presses the transfer member 20 against the circuit board 11 is uniformly applied to each projecting holding portion 32 that is pressed against the circuit board 11 . In other words, it is possible to prevent the micro light emitting diode chip 50 held by a portion of the protrusion holding portion 32 from being pressed against the circuit board 11 with a high pressure. If the micro light emitting diode chip 50 held by a part of the protrusion holding part 32 is pressed against the circuit board 11 with high pressure, the micro light emitting diode chip 50 may be broken by the high pressure. Therefore, it is preferable that the micro light-emitting diode chip 50 held by a part of the projecting holding portion 32 is prevented from being pressed against the circuit board 11 with a high pressure.

The anisotropic conductive adhesive layer is heated while the transfer member 20 is pressed against the circuit board 11 . By heating the anisotropic conductive adhesive layer, the circuit board 11 and the micro light emitting diode chip 50 are bonded together. Moreover, according to the anisotropic conductive adhesive layer, conductivity can be exhibited in the pressing direction. Therefore, each electrode 51 of the micro light emitting diode chip 50 can be electrically connected to the circuit 13 facing the pressing direction.

Here, since the substrate 31 of the transfer member 20 is hard to be deformed by heat, specifically, the coefficient of linear expansion of the substrate 31 is 10×10 ⁻⁵ /K or less, more preferably 5×10 ⁻⁵ /K or less. Therefore, even if the transfer member 20 is heated when the anisotropic conductive adhesive layer is heated, the circuit board 11 and the transfer member 20 are less likely to be misaligned. That is, the micro light emitting diode chip 50 can be accurately transferred from the transfer member 20 to the circuit board 11 .

Also, the adhesiveness of the adhesive layer 35 is reduced while the transfer member 20 is being pressed against the circuit board 11 . That is, the adhesive layer 35 is heated, cooled, or irradiated with ultraviolet rays. In addition, when the adhesiveness of the adhesive layer 35 is reduced by heating, the heat when heating the above-described anisotropic conductive adhesive layer may be used. By reducing the adhesiveness of the adhesive layer 35 , the micro light emitting diode chip 50 can be easily peeled off from the adhesive layer 35 .

In addition, when the adhesiveness of the adhesive layer 42 of the chip substrate 40 is lowered, the adhesiveness of the adhesive layer 35 of the transfer member 30 should be adjusted so that the adhesiveness 42 of the adhesive layer 35 of the transfer member 30 is not lowered. It is preferable that the technique for lowering the adhesiveness is different from the technique for lowering the adhesiveness of the adhesive layer 42 of the chip substrate 40 .

After that, as shown in FIG. 22C, the holding member 30 is separated from the circuit board 11 and the holding member 30 is removed. Through the above steps, the plurality of micro light-emitting diode chips 50 held by the holding member 30 of the transfer member 20 are electrically connected to the circuit 13 of the circuit board 11, and the holding member 30 of the transfer member 20 is transferred to the circuit board. 11 are collectively transcribed, that is, collectively transcribed.

In the above example, the first light-emitting diode chip 50R, the second light-emitting diode chip 50G, and the third light-emitting diode chip 50B can be collectively transferred to the circuit board 11, and the light-emitting board 10 capable of emitting full-color light can be efficiently manufactured. can be produced efficiently.

By the way, as described above, the adhesive stamp of Patent Document 1 is repeatedly used in the pick-and-place process from the wafer to the circuit board in the manufacturing process of the light-emitting substrate. It is difficult to increase the productivity of manufacturing a light emitting substrate by arranging light emitting diode chips on a circuit board. On the other hand, according to the holding member 30 of the present embodiment, the micro light emitting diode chips 50 can be held in a plurality of regions of the holding member 30 from the chip substrate 40 which is a substrate obtained by temporarily transferring the micro light emitting diode chips from the wafer. can be done. By pressing the transfer member 20 holding the micro light emitting diode chips 50 on the holding member 30 against the circuit board 11 , the micro light emitting diode chips 50 can be transferred to the circuit board 11 . Thus, in the manufacturing process of the light emitting substrate 10, holding and peeling of the micro light emitting diode chip 50 via the adhesive layer 35 of the holding member are performed only once. Therefore, since the adhesiveness of the adhesive layer 35 does not decrease during the manufacture of the light emitting substrate, the light emitting substrate 10 can be manufactured with high productivity. Furthermore, since the micro light-emitting diode chips 50 can be collectively transferred to the circuit board 11, the light-emitting substrate 10 can be easily manufactured, and the productivity of the light-emitting substrate 10 can be improved.

In addition, repeating the pick-and-place process using the adhesive stamp of Patent Document 1 means that the adhesive stamp is reciprocated between the wafer and the circuit board, so it takes time to produce the light-emitting substrate, which reduces productivity. it gets lower. On the other hand, according to the method of manufacturing the transfer member 20 and the method of manufacturing the light emitting substrate 10 of the present embodiment, the micro light emitting diode chip 50 is held by the holding member 30 by moving the holding member 30 relative to the chip substrate 40 . By pressing the transfer member 20 holding the micro light emitting diode chips 50 against the circuit board 11, the light emitting board 10 can be manufactured. The relative movement of the holding member 30 with respect to the chip substrate 40 is very small compared to the reciprocation between the adhesive stamp wafer and the circuit board. Therefore, according to the method for manufacturing the transfer member 20 and the method for manufacturing the light emitting substrate 10 of the present embodiment, the time for manufacturing the light emitting substrate 10 can be shortened. That is, the light emitting substrate 10 can be manufactured with high productivity.

Furthermore, in the holding member 30 of this embodiment, the base material 31 has the positioning mark M2. The positioning mark M2 and the positioning mark M3 of the chip substrate 40 allow the micro light emitting diode chip 50 to be held by the holding member 30 with high accuracy. Further, the micro light-emitting diode chip 50 can be transferred from the transfer member 20 to the circuit board 11 with high precision by the positioning mark M2 and the positioning mark M1 of the circuit board 11. FIG. That is, the light emitting substrate 10 can be manufactured with high productivity.

Further, in the present embodiment, the pitches pa1 and pa2 of the arrangement of the projecting holding portions 32 of the holding member 30 are integral multiples of the pitches pb1 and pb2 of the arrangement of the micro light emitting diode chips 50 of the chip substrate 40 . Therefore, by positioning the chip substrate 40 and the holding member 30 , it is possible to manufacture the transfer member 20 in which one micro light-emitting diode chip 50 is arranged with high accuracy in each projecting holding portion 32 of the holding member 30 . . By using this transfer member 20, the light emitting substrate 10 can be manufactured with high productivity.

Furthermore, in the holding member 30 of the present embodiment, the coefficient of linear expansion of the base material 31 is 10×10 ⁻⁵ /K or less, more preferably 5×10 ⁻⁵ /K or less. Since the base material 31 is less likely to be deformed by heat, even if the transfer member 20 is heated in the manufacturing process of the light emitting substrate 10, the circuit board 11 and the transfer member 20 are less likely to be misaligned. The micro light emitting diode chip 50 can be accurately transferred from the transfer member 20 to the circuit board 11 . That is, the light emitting substrate 10 can be manufactured with high productivity.

In addition, in the holding member 30 of the present embodiment, the Young's modulus of the projecting structure that is the main body of the projecting holding portion 32 is 10 GPa or less, more preferably 5 GPa or less. Since the protruding structure 33 has flexibility, when the chip substrate 40 contacts the protruding holding part 32 in the manufacturing process of the transfer member 20, a part of the protruding holding part 32 is pressed against the micro LED chip with a high contact pressure. 50 and breakage of the micro light emitting diode chip 50 can be avoided. Further, when the transfer member 20 is pressed against the circuit board 11 in the manufacturing process of the light emitting substrate 10, part of the projecting holding portion 32 is pressed against the micro light emitting diode chip 50 with a high pressure, and the micro light emitting diode chip 50 is destroyed. can be avoided. That is, the transfer member 20 and the light emitting substrate 10 can be manufactured with high productivity.

As described above, the holding member 30 of the present embodiment is a holding member that holds a plurality of micro light-emitting diode chips 50, and is composed of a base material 31 and two-dimensional substrates arranged on one surface of the base material 31 regularly. A plurality of arranged projecting holding portions 32 are provided, and each projecting holding portion 32 has an adhesive layer 35 having adhesiveness. According to such a holding member 30 , the adhesive layer 35 of each projecting holding portion 32 holds the micro light emitting diode chip 50 only once during the manufacturing process of the transfer member 20 . Further, in the manufacturing process of the light emitting substrate 10, the adhesive layer 35 of each projecting holding portion 32 is removed from the micro light emitting diode chip 50 only once. Therefore, the adhesiveness of the adhesive layer 35 is less likely to decrease during the manufacturing of the transfer member 20 and the light emitting substrate 10 , and the productivity of the transfer member 20 and the light emitting substrate 10 are less likely to decrease. That is, the transfer member 20 having the micro light emitting diode chips 50 arranged on the holding member 30 can be manufactured with high productivity. can be manufactured with

Various modifications can be made to the above-described embodiment.

The chip substrate 40 of the present embodiment has an adhesive layer 42 having a property that the adhesiveness is reduced by ultraviolet irradiation. Any material can be used as long as it can selectively reduce the tackiness of the region. The chip substrate 40 of the present invention may be one whose stickiness is reduced by laser irradiation, heating, or cooling, for example. However, from the viewpoint of ease of reducing the adhesiveness only in a specific region without affecting the surroundings, the adhesive layer 42 of the chip substrate 40 of the present invention is one whose adhesiveness is reduced by ultraviolet irradiation or laser irradiation. is preferred, and those whose adhesiveness is reduced by UV irradiation are more preferred.

Similarly, the method for manufacturing the transfer member 20 of the present embodiment has a step of reducing the adhesiveness of the adhesive layer 42 of the chip substrate 40 by irradiating ultraviolet rays. The adhesive layer 42 of the chip substrate 40 may be made less adhesive by, for example, laser irradiation, heating, or cooling. However, from the viewpoint of ease of reducing the adhesiveness only in a specific region without affecting the surroundings, the method for manufacturing the transfer member 20 of the present invention is to remove the adhesive layer 42 of the chip substrate 40 by ultraviolet irradiation or laser irradiation. Those that reduce the adhesiveness are preferable, and those that reduce the adhesiveness by irradiation with ultraviolet rays are more preferable.

The transfer member 20 of the present embodiment has three types of micro light-emitting diode chips 50: a first light-emitting diode chip 50R, a second light-emitting diode chip 50G, and a third light-emitting diode chip 50B. 20 is not limited to this, as long as it has two or more types of micro light emitting diode chips 50 . In other words, the transfer member 20 of the present embodiment includes three types of micro light emitting diode chips 50, the first light emitting diode chip 50R, the second light emitting diode chip 50G and the third light emitting diode chip 50B, which are arranged close to each other. However, the transfer member 20 of the present invention is not limited to this, and two or more kinds of micro light emitting diode chips 50 arranged in the vicinity form one pixel. may be used for manufacturing the light-emitting substrate 10 forming the .

Further, as shown in FIG. 23, the projecting structure 33 of the projecting holding portion 32 of the holding member 30 may include a base portion 33a and a plurality of fine extension portions 33b supported on the base portion 33a. . As shown, each fine extension 33b is finer than the base 33a. The fine extensions 33b are two-dimensionally arranged on the base 33a. Since each fine extension 33b can bend, the fine extension 33b has higher flexibility than the base 33a. With such a configuration of the protruding structure 33, the protruding structure 33 can have higher flexibility. Therefore, when holding the micro light emitting diode chip 50 on the holding member 30, it is possible to more effectively prevent a part of the projecting holding part 32 from contacting the micro light emitting diode chip 50 of the chip substrate 40 with a high contact pressure. can do. Further, when the micro light emitting diode chip 50 is arranged on the circuit board 11 using the transfer member 20, the micro light emitting diode chip 50 held by a part of the projecting holding part 32 is pressed against the circuit board 11 with a high pressure. can be avoided more effectively. That is, damage to the micro light emitting diode chip 50 is more effectively avoided.

Further, in the above-described embodiment, the protruding structures 33 are formed on the base material 31 using the photolithography technique or the imprint technique. However, the projecting structure 33 may be formed integrally with the base material 31 . The protruding structure 33 can be formed integrally with the base 31 by dry etching the material forming the base 31 or by imprinting the same material as the base 31 on the base 31 . can. When the protruding structures 33 are integrally formed with the base material 31, no interface is formed between the protruding structures 33 and the base material 31, so that the separation between the protruding structures 33 and the base material 31 is effectively prevented. can be suppressed. Moreover, since the protruding structures 33 can be formed together with the base material 31, the cost of forming the protruding structures 33 can be reduced.

Also, the adhesive layer 35 may be provided not only at the tips of the protruding structures 33 but also between the protruding structures 33 . Furthermore, the adhesive layer 35 may be provided on the entire surface of the holding member 30 on which the projecting structures 33 are formed. In this case, the adhesive layer 35 can be easily provided by coating the surface of the holding member 30 on which the projecting structures 33 are formed, for example.

Note that the above-described light-emitting substrate 10 may be used, for example, in a lighting device other than the display device 1 .

REFERENCE SIGNS LIST 1 display device 5 display surface 7 diffusion layer 10 light emitting substrate 11 circuit board 13 circuit 20 transfer member 30 holding member 31 base material 32 projecting holding portion 32R first projecting holding portion 32G second projecting holding portion 32B third projecting holding portion 33 projection Structure 35 Adhesive layer 40 Chip substrate 41 Chip substrate 42 Adhesive layer 45 Empty area 50 Micro light emitting diode chip 50R First light emitting diode chip 50G Second light emitting diode chip 50B Third light emitting diode chip 51 Electrode 60 Photomask 60a Shielding part 60b Transmission unit 80 Camera 90 Transfer member manufacturing apparatus 91 Control unit 92 Holding member holding unit 93 Chip substrate holding unit 94 Photomask holding unit 95 Ultraviolet light sources R1 to R15 First to fifteenth regions M1, M2, M3, M4 Positioning marks Pa1, Pa2, Pb1, Pb2 Pitch

Claims (12)

A holding member for holding a plurality of light-emitting diode chips of two or more types,
a plate-like substrate;
a plurality of protruding holding parts arranged regularly two-dimensionally on one surface of the base material, each for holding one of the light emitting diode chips;
The projecting holding part has a projecting structure that is a main body, and a first adhesive layer made of an acrylic adhesive provided at the tip of the projecting structure , and is perpendicular to the plate surface of the base material. holding member capable of compressively deforming to a thickness of the light emitting diode chip or more. The holding member according to claim 1,
Young's modulus of the projecting structure is 10 GPa or less,
The holding member, wherein the protruding structure has a length of 5 μm or more in a direction perpendicular to the plate surface of the base material. The holding member according to claim 1 or 2,
The first adhesive layer is a holding member whose adhesiveness is reduced by heating, cooling, or ultraviolet irradiation. a holding member according to any one of claims 1 to 3;
a plurality of the light-emitting diode chips of two or more types held by the projecting holding portion; and a transfer member. A chip substrate used for holding the light emitting diode chip in the holding member according to any one of claims 1 to 3,
a plate-like chip base material;
a second adhesive layer laminated on one surface of the chip substrate;
a plurality of the light-emitting diode chips regularly arranged two-dimensionally on the surface of the second adhesive layer opposite to the surface on the chip substrate side;
The second adhesive layer has higher adhesiveness than the first adhesive layer of the holding member, and becomes lower in adhesiveness than the first adhesive layer of the holding member by ultraviolet irradiation, laser irradiation, heating, or cooling. Chip substrate. A chip substrate according to claim 5,
The chip base material transmits ultraviolet rays,
The second adhesive layer is a chip substrate whose adhesiveness is reduced by ultraviolet irradiation. The chip substrate according to claim 5 or 6,
The chip substrate, wherein the pitch of the arrangement of the projecting holding portions is an integral multiple of the pitch of the arrangement of the light emitting diode chips. a plate-shaped chip substrate; a second adhesive layer that is laminated on one plate surface of the chip substrate and whose adhesiveness is reduced by ultraviolet irradiation, laser irradiation, heating or cooling; A first chip substrate having a plurality of first light emitting diode chips regularly arranged two-dimensionally on a surface opposite to the surface facing the chip substrate is held according to any one of claims 1 to 3. A first step of contacting the member;
In the second adhesive layer of the first chip substrate, the adhesiveness of the region where the first light emitting diode chip is arranged and which is in contact with the projecting holding portion for holding the first light emitting diode chip is measured by irradiating ultraviolet rays. , a second step of reducing by laser irradiation, heating or cooling;
a third step of separating the first chip substrate from the holding member and holding the first light emitting diode chip on the projecting holding portion;
A plate-shaped chip base material, a second adhesive layer laminated on one surface of the chip base material, the adhesiveness of which is reduced by ultraviolet irradiation, laser irradiation, heating or cooling, and the chip of the second adhesive layer A second chip substrate having a plurality of second light emitting diode chips different in type from the plurality of first light emitting diode chips regularly arranged two-dimensionally on a surface opposite to the surface facing the substrate is mounted on the holding member. A fourth step of contacting;
In the second adhesive layer of the second chip substrate, the adhesiveness of the region where the second light emitting diode chip is arranged and which is in contact with the protrusion holding portion for holding the second light emitting diode chip is irradiated with ultraviolet rays. , a fifth step of reducing by laser irradiation, heating or cooling;
and a sixth step of separating the second chip substrate from the holding member and holding the second light emitting diode chip on the projecting holding portion. A method for manufacturing a transfer member according to claim 8, comprising:
the chip base materials of the first chip substrate and the second chip substrate transmit ultraviolet rays;
The adhesiveness of the second adhesive layers of the first chip substrate and the second chip substrate is reduced by ultraviolet irradiation,
In the second step and the fifth step, ultraviolet rays are transmitted from a side opposite to the second adhesive layer side of the first chip substrate or the second chip substrate, and a shielding portion that shields the ultraviolet rays and the ultraviolet rays are transmitted. A method for manufacturing a transfer member, comprising a step of irradiating the second adhesive layer through a photomask having a transmission portion. The apparatus for manufacturing a transfer member according to claim 4,
A plate-shaped chip base material, a second adhesive layer laminated on one surface of the chip base material, the adhesion of which is reduced by ultraviolet irradiation, and a surface opposite to the chip base side of the second adhesive layer a chip substrate holding part for holding a chip substrate having a plurality of the light emitting diode chips regularly arranged two-dimensionally on the surface of the
an ultraviolet light source for irradiating the second adhesive layer of the chip substrate with ultraviolet light;
a photomask holding portion holding a photomask having a shielding portion for blocking ultraviolet rays and a transmitting portion for transmitting ultraviolet rays;
a holding member holding portion that holds the holding member;
a camera for observing the chip substrate holding portion, the photomask holding portion, the holding member held by the holding member holding portion, the chip substrate, and the photomask;
a control unit that controls the chip substrate holding unit, the ultraviolet light source, the photomask holding unit, the holding member holding unit, and the camera;
The chip substrate holding part, the photomask holding part, and the holding member holding part can move independently,
The control unit positions the holding member and the chip substrate using observation results of the holding member and the chip substrate by the camera, and uses observation of the chip substrate and the photomask by the camera. A transfer member manufacturing apparatus that positions the chip substrate and the photomask. 5. The light emitting diode chips of the transfer member according to claim 4 are electrically connected to a circuit of a circuit board, and a plurality of the light emitting diode chips are collectively mounted on the circuit board from the holding member of the transfer member. comprising a step of transferring,
A method for manufacturing a light-emitting substrate. A method for manufacturing a light-emitting substrate according to claim 11,
The adhesiveness of the first adhesive layer of the holding member is reduced by heating, cooling, or ultraviolet irradiation,
The step of collectively transferring the plurality of light-emitting diode chips from the holding member of the transfer member to the circuit board includes:
Manufacture of a light-emitting substrate, further comprising: reducing the adhesiveness of the first adhesive layer of the holding member by heating, cooling, or ultraviolet irradiation; and peeling the light-emitting diode chip from the first adhesive layer. Method.

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