JP7623788B2 - Pressurizing device, manufacturing device and manufacturing method for element array - Google Patents

Description

The present invention relates to a pressure device that applies pressure to an element array consisting of multiple elements arranged on a mounting substrate, and a manufacturing device and method for the element array.

The following method is known as a method for manufacturing an element array consisting of multiple elements (e.g., light-emitting elements) on a mounting substrate. That is, multiple elements are arranged in an array on a mounting substrate provided with a conductive bonding material such as ACF (Anisotropic Conductive File) or ACP (Anisotropic Conductive Paste), or a eutectic metal such as Sn, Pb, Ag, Au, Bi, In, Ca, Cu, or Ge. Then, the multiple elements arranged in the array (element array) are pressed with a pressure plate made of a metal such as stainless steel, and mounted on the mounting substrate via the conductive bonding material. In this way, an element array can be manufactured on the mounting substrate.

When applying pressure to an element array with a pressure plate, attempts have been made to improve the uniformity of pressure between multiple elements by interposing a flexible layer having fluidity between the pressure plate and the element array, as in the invention described in Patent Document 1, for example.

However, in the invention described in Patent Document 1, because the flexible layer has fluidity, when the pressure applied by the pressure plate is increased, the flexible layer easily deforms, making it impossible to apply high pressure to the element array, and also making it impossible to apply uniform pressure to the multiple elements arranged on the mounting board, which may result in mounting defects.

JP 2004-296746 A

The present invention was made in consideration of the above-mentioned circumstances, and its purpose is to provide a pressure application device, manufacturing device, and manufacturing method for an element array that can stably manufacture an element array on a mounting substrate.

In order to achieve the above object, a pressurizing device for an element array according to the present invention comprises:
a pressure plate having a pressure section for applying pressure to an element array made up of a plurality of elements arranged on a mounting substrate;
The pressure applying portion has a plate-shaped elastic material,
The thickness of the elastic material is 0.5 to 2.0 times the thickness of the element.

In the element array pressure application device of the present invention, the pressure application section has a plate-shaped elastic material. Therefore, when pressure is applied by the pressure plate, it is possible to apply pressure to the element array, which is made up of multiple elements arranged on the mounting board, via the elastic material.

In particular, in the element array pressure application device according to the present invention, the thickness of the elastic material is 0.5 to 2.0 times the thickness of the element. When the thickness of the elastic material relative to the thickness of the element is set within this range, the elastic material has an appropriate thickness, so that the elastic material is easily deformed to conform to the surface shape of the element array, etc., and it becomes possible to apply pressure evenly across the entire element array via the elastic material. In addition, the elastic material has an appropriate hardness, so that it becomes possible to apply sufficient pressure to the element array via the elastic material. Therefore, pressure can be applied uniformly to multiple elements arranged on the mounting board.

Furthermore, when the elastic material deforms, pressure is generated accordingly, but if the thickness of the elastic material relative to the thickness of the element is set within the range described above, the pressure will not become excessively large enough to affect the pressure applied by the pressure plate. Therefore, when applying pressure with the pressure plate, it is possible to prevent the pressure force from the pressure plate from being unevenly distributed, and pressure can be applied uniformly to multiple elements arranged on the mounting board. Therefore, with the element array pressure device of the present invention, mounting defects can be prevented, and element arrays can be stably manufactured on the mounting board.

The elastic material may be provided on the surface of the pressure plate. With this configuration, when the pressure plate is heated during pressure application by the pressure plate, the heat of the pressure plate is easily transferred to the elastic material, and multiple elements can be successfully mounted on the mounting board, for example, using a conductive bonding material provided on the mounting board.

The pressure applying unit has a plate-shaped hard material with a higher surface accuracy than the surface of the pressure plate, and the hard material is provided on the surface of the elastic material, and the surface of the hard material may further include another elastic material. Since the surface accuracy (e.g., flatness, smoothness, etc.) of the hard material is higher than the surface accuracy (e.g., flatness, smoothness, etc.) of the pressure plate, by providing a hard material between each elastic material, it is possible to arrange the outer elastic material that constitutes the contact surface with the element array in a state close to parallel to the horizontal plane. Therefore, the contact (parallelism, etc.) between the surface of the element array, etc. and the pressure applying surface (contact surface with the element array) of the pressure applying unit (elastic material) is improved, and it is possible to apply pressure uniformly to the multiple elements arranged on the mounting board. Therefore, it is possible to effectively prevent mounting defects from occurring and stably manufacture the element array on the mounting board.

In addition, by deforming the elastic material provided on the surface of the pressure plate, the surface of the element array, etc. and the surface of the outer elastic material that forms the contact surface with the element array, etc., tend to become parallel, allowing more uniform pressure to be applied to the multiple elements that make up the element array.

The pressure unit may have a plate-shaped hard material with a higher surface accuracy than the surface of the pressure plate, the hard material being provided on the surface of the pressure plate, and the elastic material being provided on the surface of the hard material. With this configuration, even if the surface accuracy of the pressure plate is not good, it is possible to directly absorb this by the hard material. Therefore, it is possible to arrange the elastic material that constitutes the contact surface with the element array in a state close to parallel to the horizontal plane, and the contact (parallelism, etc.) between the surface of the element array, etc. and the pressure surface (contact surface with the element array) of the pressure unit (elastic material) is good. Therefore, it is possible to apply pressure uniformly to multiple elements arranged on the mounting board, effectively preventing mounting defects, and stably manufacturing the element array on the mounting board.

Preferably, at least one of the hard materials and at least one of the elastic materials are alternately laminated on the surface of the pressure plate. With this configuration, it is possible to effectively obtain the above-mentioned effects obtained by providing the pressure plate with a hard material and an elastic material, and pressure can be applied more uniformly to multiple elements arranged on the mounting board.

Preferably, a water-repellent layer that has been treated to be water-repellent is formed on the surface of the elastic material. With this configuration, when pressure is applied to the element array formed on the mounting board through the surface of the elastic material, it is possible to prevent the elements from adhering to the surface of the elastic material, and it is possible to effectively prevent mounting defects. In addition, when mounting multiple elements on a mounting board using a conductive bonding material, even if the pressure portion comes into contact with the conductive bonding material when pressure is applied by the pressure plate, it is possible to prevent the conductive bonding material from adhering to the pressure portion by the water-repellent layer. Therefore, it is possible to prevent damage to the pressure plate caused by the conductive bonding material adhering to the pressure portion.

Preferably, the thickness of the water-repellent layer is smaller than the thickness of the elastic material. This configuration effectively prevents elements from adhering to the surface of the elastic material.

The thickness of the element may be 50 μm or less. Even when the pressure is applied to an element array made up of such tiny elements, the elastic material deforms appropriately to conform to the surface shape of the element array, etc., so that pressure can be applied uniformly to the multiple elements that make up the element array.

In order to achieve the above object, the manufacturing apparatus for an element array according to the present invention has any one of the pressure devices described above. By mounting an element array on a mounting substrate using any one of the pressure devices described above, it becomes possible to apply uniform pressure to multiple elements arranged on the mounting substrate, preventing mounting defects and enabling the element array to be stably manufactured on the mounting substrate.

The device further includes a mounting table on which the mounting substrate is placed, a supply table on which a supply substrate on which a plurality of the elements are arranged is placed, and a transport device that moves to the supply table to pick up the plurality of elements from the supply substrate and moves to the mounting table to transfer the plurality of the picked-up elements to the mounting substrate, and the pressure plate may apply pressure to the element array consisting of the plurality of the elements transferred to the mounting substrate by the transport device.

By configuring in this way, even when multiple elements are transferred from a supply substrate to a mounting substrate all at once in a so-called mass transfer process and pressure is applied to an element array consisting of these elements using a pressure plate, it is possible to stably manufacture the element array on the mounting substrate, thereby improving the yield during manufacturing.

In order to achieve the above object, a method for manufacturing an element array according to the present invention includes the steps of:
preparing a mounting substrate on which a plurality of elements are arranged;
and applying pressure to the plurality of elements arranged on the mounting board using a pressure device provided with a plate-shaped elastic material having a thickness 0.5 to 2.0 times that of the elements.

In the mounting method for an element array according to the present invention, a pressure device provided with a plate-shaped elastic material having a thickness 0.5 to 2.0 times that of the elements is used to apply pressure to multiple elements arranged on a mounting board. This allows the elastic material to deform appropriately to conform to the surface shape of the element array, etc., and makes it possible to apply pressure to the entire element array evenly with sufficient pressure via the elastic material. It is also possible to prevent the pressure applied by the pressure plate from being unevenly distributed, making it possible to apply pressure uniformly to multiple elements arranged on the mounting board. Therefore, the mounting method for an element array according to the present invention prevents mounting defects and allows the element array to be stably manufactured on the mounting board.

Preferably, the multiple elements are connected to the mounting substrate by applying pressure to the multiple elements toward a conductive bonding material provided on the mounting substrate. This makes it possible to mount multiple elements on the mounting substrate using a conductive bonding material such as ACF (Anisotropic Conductive File) or ACP (Anisotropic Conductive Paste), and thus makes it possible to easily manufacture an element array on the mounting substrate.

FIG. 1 is a schematic side view showing a pressurizing device according to a first embodiment of the present invention. FIG. 2 is a block diagram showing the functional configuration of an element array manufacturing apparatus having the pressure device shown in FIG. FIG. 3A is a cross-sectional view showing a process of transferring an element from a supply substrate to a mounting substrate by mass transfer. FIG. 3B is a cross-sectional view showing a process subsequent to that of FIG. 3A. FIG. 3C is a cross-sectional view showing a process subsequent to that of FIG. 3B. FIG. 4 is a schematic side view showing a pressure device according to a second embodiment of the present invention. FIG. 5 is a schematic side view showing a pressure device according to a third embodiment of the present invention. FIG. 6 is a schematic side view showing a pressure device according to a fourth embodiment of the present invention.

The present invention will now be described with reference to the embodiments shown in the drawings.

First embodiment As shown in FIG. 1, a pressure device 10 according to a first embodiment of the present invention has a pressure plate 11. The pressure plate 11 is made of a metal such as stainless steel, and pressurizes a non-pressurized object (in this embodiment, a plurality of elements 40a to 40c). The pressure device 10 constitutes a part of an element array 40 manufacturing device that manufactures an element array 40 consisting of a plurality of elements 40a to 40c on a mounting substrate 30. In the following, the X axis corresponds to the width direction of the mounting substrate 30, the Y axis corresponds to the depth direction of the mounting substrate 30, and the Z axis corresponds to the height direction of the mounting substrate 30. The X axis and the Y axis are parallel to the horizontal plane, the Z axis is parallel to the vertical line, and the X axis, the Y axis, and the Z axis are perpendicular to each other. In FIG. 1 and the like, for convenience of explanation, the elements 40a to 40c are illustrated larger than the other components.

2, the manufacturing device for the element array 40 includes a control unit 91, a pressure control mechanism 92, a drive mechanism 93, a heating mechanism 94, and a temperature control mechanism 95, and the above-mentioned units control the pressure plate 11 and the like. The drive mechanism 93 drives the pressure plate 11 in the vertical direction. The pressure control mechanism 92 controls the magnitude of the pressure force (load amount) when the pressure plate 11 is driven. The heating mechanism 94 is, for example, a heater, and is built into the pressure plate 11 shown in FIG. 1 and the mounting table 20 on which the mounting substrate 30 and the like are placed. The temperature control mechanism 95 controls the heating temperature by the heating mechanism 94 to control the heating temperature of the pressure plate 11 and the mounting table 20. The control unit 91 controls the operation of the pressure control mechanism 92, the drive mechanism 93, the heating mechanism 94, and the temperature control mechanism 95.

1, the mounting substrate 30 also extends in the Y-axis direction in the figure, and has a circular or rectangular outer shape. The material of the mounting substrate 30 in this embodiment is a glass epoxy material. However, the material of the mounting substrate 30 is not limited to this, and may be, for example, SiO ₂ or Al ₂ O ₃ as a glass substrate, or elastomers such as polyimide, polyamide, polypropylene, polyether ether ketone, urethane, silicone, polyethylene terephthalate, and polyethylene naphthalate as a flexible substrate, or glass wool.

The mounting board 30 is placed on the mounting stand 20 via the mounting support board 32. A conductive bonding material (not shown) is formed in advance on the surface of the mounting board 30. This conductive bonding material electrically and mechanically connects the mounting board 30 and the elements 40a to 40c by anisotropic conductive particle connection or bump pressure connection, and hardens when heated. Examples of the conductive bonding material include ACF, ACP, NCF, and NCP. The thickness of the conductive bonding material is preferably 1.0 to 10,000 μm.

Wiring 31_1 and wiring 31_2 are formed in a predetermined pattern on mounting board 30. In the illustrated example, wiring 31_1, 31_2 are formed in pairs, and multiple pairs of wiring 31_1, 31_2 are arranged along the X-axis direction. Any of elements 40a to 40c can be connected to wiring 31_1, 31_2 via a conductive bonding material.

The mounting auxiliary board 32 is composed of a flat, thin plate (rigid body). The mounting auxiliary board 32 is placed on the mounting base 20 and is composed of a member with relatively high surface precision (flatness, smoothness, etc.). The surface precision of the mounting auxiliary board 32 is superior to the surface precision of the mounting base 20, and the surface of the mounting auxiliary board 32 (particularly the surface on which the mounting base 20 is placed) has fewer projections and recesses (i.e., is smooth) and a smaller inclination with respect to the horizontal plane (i.e., is flat) compared to the surface of the mounting base 20.

The mounting auxiliary substrate 32 is made of a hard material, and in this embodiment, the mounting auxiliary substrate 32 is made of a glass substrate. However, the material constituting the mounting auxiliary substrate 32 is not limited to this, and may be made of, for example, quartz glass (SiO ₂ ), diamond, or ceramics such as sapphire, alumina (Al ₂ O ₃ ), cordierite (2MgO.2Al _{2 O} 3.5SiO ₂ ), aluminum nitride (AlN), silicon nitride (SiN), silicon carbide (SiC), and zirconia (ZrO ₂ ). As for surface accuracy, the surface roughness Ra of the mounting auxiliary substrate 32 is preferably 0.1 to 2.0 μm, and more preferably 0.1 to 1.0 μm.

In the illustrated example, the thickness of the mounting auxiliary substrate 32 is thicker than the mounting substrate 30 or the elements 40a to 40c. The thickness of the mounting auxiliary substrate 32 is preferably 1 mm to 20 mm. A water-repellent layer (not shown) may be formed on the surface of the mounting auxiliary substrate 32 by performing a water-repellent treatment. The water-repellent treatment is performed by applying, for example, a fluorine-based resin to the surface of the mounting auxiliary substrate 32. The thickness of the water-repellent layer is preferably 8 μm or less.

In this way, by placing the mounting substrate 30 on the mounting auxiliary substrate 32 with excellent surface accuracy, the mounting substrate 30 can be stably positioned without tilting relative to the horizontal plane. In addition, by forming a water-repellent layer on the surface of the mounting auxiliary substrate 32, even if the pressure unit 12 comes into contact with the conductive bonding material formed on the mounting substrate 30 when the pressure plate 11 presses the element array 40 and the conductive bonding material flows toward the mounting auxiliary substrate 32, the water-repellent layer can prevent the conductive bonding material from adhering to the mounting auxiliary substrate 32. As a result, it is also possible to prevent the conductive bonding material from adhering to the pressure unit 12, and damage to the pressure plate 11 can be prevented.

The elements 40a to 40c are arranged in an array on the substrate 30. An array refers to a state in which the elements 40a to 40c are arranged in multiple rows and multiple columns according to a predetermined pattern, and the spacing in the row and column directions may be the same or different.

The elements 40a to 40c are arranged on a display substrate as RGB pixels, and on an illumination substrate as light emitters for the backlight. The element 40a is a red light element, the element 40b is a green light emitting element, and the element 40c is a blue light emitting element.

In this embodiment, the elements 40a to 40c are micro-light-emitting elements (micro-LED elements), and their size (width x depth) is, for example, 5 μm x 5 μm to 50 μm x 50 μm. The thickness (height) of the elements 40a to 40c is, for example, 50 μm or less.

A pair of electrodes (bumps) 41_1 and 41_2 protrude from one surface of each of the elements 40a to 40c (the surface on which the mounting substrate 30 is disposed). The pair of electrodes 41_1 and 41_2 are connected to wiring 31_1 and 31_2 provided on the mounting substrate 30, respectively. The thickness (height) of the electrodes 41_1 and 41_2 is, for example, 3 μm or less.

When the elements 40a to 40c are pressed by the pressure plate 11, the conductive bonding material sandwiched between the electrodes 41_1, 41_2 of the elements 40a to 40c and the wiring 31_1, 31_2 protruding from the mounting substrate 30 is compressed, and the compressed portions become conductive. As a result, the wiring 31_1, 31_2 and the electrodes 41_1, 41_2 are brought into a conductive state, and an element array 40 consisting of multiple elements 40a to 40c is mounted on the mounting substrate 30.

The pressure plate 11 has a pressure section 12 that applies pressure to an element array 40 consisting of a number of elements 40a to 40c arranged on a mounting substrate 30. The pressure section 12 has an elastic material 14.

The elastic material 14 is flat (sheet-shaped) and is provided on the surface of the pressure plate 11. The elastic material 14 is fixed to the surface of the pressure plate 11 by adhesive means such as glue or joining means. When pressure is applied by the pressure plate 11, the surface of the elastic material 14 (the surface on which the elements 40a to 40c are arranged) forms the contact surface or pressure surface with the element array 40. That is, in the pressure device 10 for the element array 40 according to this embodiment, when pressure is applied by the pressure plate 11, it is possible to apply pressure to the element array 40, which is made up of multiple elements 40a to 40c arranged on the mounting substrate 30, via the elastic material 14.

The surface area of one side of the elastic material 14 located on the side where the elements 40a to 40c are arranged is preferably equal to or larger than the surface area of the element array 40 or the mounting substrate 30. In this case, when pressure is applied by the pressure plate 11, it is possible to apply pressure to the entire surface of the element array 40 via the elastic material 14. However, the surface area of the elastic material 14 may be smaller than the surface area of the element array 40 or the mounting substrate 30.

In this embodiment, the elastic material 14 is made of a carbon sheet. However, the material constituting the elastic material 14 is not limited to this, and may be made of a sheet made of, for example, a heat-resistant resin such as polyimide, polytetrafluoroethylene (Teflon (registered trademark)), polypropylene, or an elastomer such as urethane, silicone, polyethylene terephthalate, or polyethylene naphthalate, or even glass wool.

The elastic material 14 is preferably made of a material with excellent thermal conductivity. By making the elastic material 14 out of such a material, when the pressure plate 11 is heated during pressure application by the pressure plate 11, the heat of the pressure plate 11 is easily transferred to the elastic material 14. Therefore, it becomes possible to transfer a sufficient amount of heat to the conductive bonding material via the elastic material 14, and the electrodes 41_1, 41_2 and the wiring 31_1, 31_2 can be efficiently and stably connected via the conductive bonding material.

A water-repellent layer 14a is formed on the surface of the elastic material 14. The water-repellent layer 14a is formed by applying a water-repellent treatment to the surface of the elastic material 14 (in the illustrated example, the surface of one side of the elastic material 14 on which the elements 40a to 40c are located). The water-repellent treatment is performed by applying, for example, a fluorine-based resin to the surface of the elastic material 14. The thickness of the water-repellent layer 14a is preferably smaller than the thickness of the elastic material 14, and is preferably 8 μm or less.

The thickness L1 of the elastic material 14 is preferably 1 mm or less. The ratio L1/L2 of the thickness L1 of the elastic material 14 to the thickness (height) L2 of the elements 40a to 40c is preferably 0.5 to 2.0. The thickness L2 of the elements 40a to 40c corresponds to the sum of the thicknesses of the element body and the electrodes 41_1, 41_2.

Next, a method for manufacturing the element array 40 on the mounting substrate 30 will be described.

First, as shown in FIG. 1, a mounting substrate 30 on which a plurality of elements 40a to 40c are arranged is prepared. The mounting substrate 30 is manufactured, for example, through the steps shown in FIG. 3A to FIG. 3C. That is, as shown in FIG. 3A, a supply substrate 80 on which a plurality of elements 40a are arranged is prepared and placed on a supply table 70. The supply substrate 80 is, for example, composed of a substrate body 81 and an adhesive layer 82 formed on the surface of the substrate body 81. The adhesive layer 82 is composed of a resin such as natural rubber, synthetic rubber, acrylic resin, or silicone rubber. The substrate body 81 may be a flexible adhesive sheet itself. The elements 40a are detachably attached in a matrix on the surface of the adhesive layer 82 at predetermined intervals in each of the X-axis direction and the Y-axis direction.

As shown in FIG. 3B, the stamp tool 61 of the transport device 60 is moved to the supply table 70, and the multiple elements 40a attached to the adhesive layer 82 are picked up from the supply substrate 80. Then, as shown in FIG. 3C, the stamp tool 61 is moved to the mounting table 20, and the picked up multiple elements 40a are transferred (placed) on the mounting substrate 30. The stamp tool 61 has multiple protrusions arranged at a predetermined interval, and the multiple elements 40a can be picked up by attaching the multiple elements 40a to an adhesive layer (not shown) formed on the surface of the protrusions. The multiple elements 40a placed on the mounting substrate 30 are attached to a conductive bonding material (not shown) formed on the mounting substrate 30.

Similarly, a supply board 80 (not shown) on which multiple elements 40b are arranged is prepared and placed on the supply table 70. Then, the stamp tool 61 is moved to the supply table 70, and multiple elements 40b are picked up from the supply board 80. The stamp tool 61 is moved to the mounting table 20, and the picked-up multiple elements 40b are transferred (placed) on the mounting board 30. Also, a supply board 80 (not shown) on which multiple elements 40c are arranged is prepared and placed on the supply table 70. Then, the stamp tool 61 is moved to the supply table 70, and multiple elements 40c are picked up from the supply board 80. The stamp tool 61 is moved to the mounting table 20, and the picked-up multiple elements 40c are transferred (placed) on the mounting board 30. This makes it possible to prepare a mounting board 30 on which multiple elements 40a to 40c are arranged, as shown in FIG. 3C.

Next, the element array 40 consisting of the multiple elements 40a-40c transferred to the mounting substrate 30 by the stamp tool 61 is pressed by the elastic material 14 provided on the surface of the pressure plate 11. The heating temperature of the pressure plate 11 during pressing is a maximum of about 500 degrees. As a result, the multiple elements 40a-40c are pressed toward the conductive bonding material provided on the mounting substrate 30, and the multiple elements 40a-40c (electrodes 41_1, 41_2) are electrically connected to the mounting substrate 30 (wiring 31_1, 31_2) via the conductive bonding material. In this manner, the element array 40 can be manufactured on the mounting substrate 30.

In the pressure device 10 for the element array 40 according to this embodiment, the thickness of the elastic material 14 is 0.5 to 2.0 times the thickness of the elements 40a to 40c. When the thickness of the elastic material 14 relative to the thickness of the elements 40a to 40c is set within this range, the elastic material 14 has an appropriate thickness, so that the elastic material 14 is easily deformed to conform to the surface shape of the element array 40, etc., and it becomes possible to apply pressure to the entire element array 40 evenly through the elastic material 14. In addition, since the elastic material 14 has an appropriate hardness, it becomes possible to apply sufficient pressure to the element array 40 through the elastic material 14. Therefore, pressure can be applied uniformly to the multiple elements 40a to 40c arranged on the mounting board 30.

When the elastic material 14 deforms, pressure is generated accordingly, but if the thickness of the elastic material 14 relative to the thickness of the elements 40a to 40c is set within the above-mentioned range, the pressure does not become excessively large enough to affect the pressure applied by the pressure plate 11. Therefore, when applying pressure with the pressure plate 11, it is possible to prevent the pressure applied by the pressure plate 11 from being unevenly distributed, and pressure can be applied uniformly to the multiple elements 40a to 40c arranged on the mounting substrate 30. Therefore, with the pressure device 10 for the element array 40 according to this embodiment, mounting defects can be prevented, and the element array 40 can be stably manufactured on the mounting substrate 30.

In addition, by setting the thickness of the elastic material 14 within the above range, when the pressure plate 11 is heated during pressure application by the pressure plate 11, the heat of the pressure plate 11 is easily transferred to the elastic material 14. Therefore, it is possible to transfer a sufficient amount of heat to the conductive bonding material via the elastic material 14, and the electrodes 41_1, 41_2 and the wiring 31_1, 31_2 can be efficiently and stably connected via the conductive bonding material.

In addition, in this embodiment, the elastic material 14 is provided on the surface of the pressure plate 11. Therefore, when the pressure plate 11 is heated during pressure application by the pressure plate 11, the heat of the pressure plate 11 is easily transferred to the elastic material 14, and the multiple elements 40a to 40c can be mounted well on the mounting substrate 30 using, for example, a conductive bonding material provided on the mounting substrate 30.

In addition, in this embodiment, a water-repellent layer 14a that has been treated to be water-repellent is formed on the surface of the elastic material 14. Therefore, when the element array 40 formed on the mounting substrate 30 is pressed through the surface of the elastic material 14, it is possible to prevent the elements 40a to 40c from adhering to the surface of the elastic material 14, and it is possible to effectively prevent mounting defects. In addition, when a plurality of elements 40a to 40c are mounted on the mounting substrate 30 using a conductive bonding material, even if the pressure unit 12 comes into contact with the conductive bonding material when pressure is applied by the pressure plate 11, it is possible to prevent the conductive bonding material from adhering to the pressure unit 12 by the water-repellent layer 14a. Therefore, it is possible to prevent damage to the pressure plate 11 caused by the conductive bonding material adhering to the pressure unit 12.

In addition, in this embodiment, the thickness of the water-repellent layer 14a is smaller than the thickness of the elastic material 14. This effectively prevents the elements 40a to 40c from adhering to the surface of the elastic material 14.

In addition, in this embodiment, the thickness of the elements 40a to 40c is 50 μm or less. Even if the element array 40 consisting of such tiny elements 40a to 40c is the target of pressure application, the elastic material 14 can be appropriately deformed to conform to the surface shape of the element array 40, etc., thereby allowing pressure to be applied uniformly to the multiple elements 40a to 40c that make up the element array 40.

In addition, in this embodiment, the transport device 60 (stamp tool 61) moves to the supply table 70 to pick up multiple elements 40a-40c from the supply substrate 80, and then moves to the mounting table 20 to transfer the picked-up multiple elements 40a-40c to the mounting substrate 30. Therefore, in so-called mass transfer, even when multiple elements 40a-40c are transferred collectively from the supply substrate 80 to the mounting substrate 30 and pressure is applied to the element array 40 consisting of these elements 40a-40c by the pressure plate 11, it is possible to stably manufacture the element array 40 on the mounting substrate 30, and the yield during manufacturing can be improved.

In addition, in this embodiment, the multiple elements 40a to 40c are connected to the mounting substrate 30 by applying pressure to the multiple elements 40a to 40c toward a conductive bonding material provided on the mounting substrate 30. Therefore, it is possible to mount the multiple elements 40a to 40c on the mounting substrate 30 using a conductive bonding material such as ACF (Anisotropic Conductive File) or ACP (Anisotropic Conductive Paste), and the element array 40 can be easily manufactured on the mounting substrate 30.

A pressure application device 110 according to a second embodiment shown in Fig. 4 has a similar configuration to the pressure application device 10 according to the first embodiment, and exerts similar effects, except for the following points: In Fig. 4, members common to the members in the pressure application device 10 according to the first embodiment are given the same reference numerals, and some of the descriptions thereof will be omitted.

As shown in FIG. 4, the pressure device 110 has a pressure plate 111. The pressure plate 111 has a pressure section 112, which differs from the pressure section 12 in the first embodiment in that the pressure section 112 has a plate-shaped hard material 13 that has a higher surface precision (flatness, smoothness, etc.) than the surface of the pressure plate 111.

The hard material 13 is composed of a thin, flat plate (rigid body). In this embodiment, the hard material 13 is provided on the surface of the pressure plate 111 (the surface on which the elements 40a to 40c are arranged). The hard material 13 is fixed to the surface of the pressure plate 111 by an adhesive or other bonding means.

The hard material 13 may be fixed to the pressure plate 111 using, for example, a clamp member (bracket). In this case, the hard material 13 can be detachably fixed to the pressure plate 111, and the hard material 13 provided on the pressure plate 111 can be easily replaced with a new hard material 13. When attaching or detaching the hard material 13, the elastic material 14 can also be attached or detached at the same time, and the elastic material 14 can be easily replaced with a new elastic material 14.

The surface precision of the hard material 13 is relatively high and is superior to the surface precision of the pressure plate 111. Compared to the surface of the pressure plate 111, the surface of the hard material 13 has fewer irregularities (i.e., is smooth) and has a smaller inclination with respect to the horizontal plane (i.e., is flat).

In this embodiment, the hard material 13 is made of a glass substrate. However, the material constituting the hard material 13 is not limited to this, and may be made of, for example, quartz glass (SiO ₂ ), diamond, or ceramics such as sapphire, alumina (Al ₂ O ₃ ), cordierite (2MgO.2Al _{2 O} 3.5SiO ₂ ), aluminum nitride (AlN), silicon nitride (SiN), silicon carbide (SiC), and zirconia (ZrO ₂ ). As for surface accuracy, the surface roughness Ra of the hard material 13 is preferably 0.1 to 2.0 μm, and more preferably 0.1 to 1.0 μm.

In this embodiment, the elastic material 14 is provided on the surface of the hard material 13. In the illustrated example, the surface of the elastic material 14 does not have the water-repellent layer 14a shown in FIG. 1, but in reality, the water-repellent layer 14a is provided. When the surface roughness Ra of the hard material 13 is set to the above range, it is possible to provide the elastic material 14 on the surface of the hard material 13 while reducing the inclination with respect to the horizontal plane, and when pressure is applied by the pressure plate 111, the contact (parallelism, etc.) between the surface of the hard material 13 and the surface of the element array 40 can be improved. In addition, the surface of the hard material 13 may be provided with a water-repellent layer 14a. In this case, it is preferable that the above-mentioned surface roughness Ra is a value including the thickness of the water-repellent layer 14a.

In addition, since the pressure plate 111 is usually made of metal, it deforms when heated, but the hard material 13 made of the above-mentioned material has a relatively small thermal expansion coefficient and is less likely to deform. Therefore, by providing the elastic material 14 on the surface of the hard material 13, when pressure is applied by the pressure plate 111, good contact is achieved between the surface of the element array 40 and the pressure surface of the pressure unit 12 (elastic material 14), making it possible to apply uniform pressure to the multiple elements 40a to 40c arranged on the mounting board 30.

The hard material 13 is preferably made of a material with a relatively high thermal conductivity. By making the hard material 13 out of such a material, when the pressure plate 111 is heated during pressure application by the pressure plate 111, the heat of the pressure plate 111 is easily transferred to the hard material 13, and the heat transferred to the hard material 13 is easily transferred to the elastic material 14. Therefore, it is possible to transfer a sufficient amount of heat to the conductive bonding material via the elastic material 14, and the electrodes 41_1, 41_2 and the wiring 31_1, 31_2 can be efficiently and stably connected via the conductive bonding material.

In the illustrated example, the thickness of the hard material 13 is thinner than the thickness of the mounting support substrate 32, but it may be thicker than the thickness of the mounting support substrate 32. The thickness of the hard material 13 is preferably 1 mm to 20 mm.

By setting the thickness of the hard material 13 within this range, when the pressure plate 111 is heated during pressure application by the pressure plate 111, the heat of the pressure plate 111 is easily transferred to the hard material 13, and the heat transferred to the hard material 13 is easily transferred to the elastic material 14. Therefore, it is possible to transfer a sufficient amount of heat to the conductive bonding material via the elastic material 14, and the electrodes 41_1, 41_2 of the elements 40a to 40c and the wiring 31_1, 31_2 can be efficiently and stably connected via the conductive bonding material.

In this embodiment, the hard material 13 is provided on the surface of the pressure plate 111, and the elastic material 14 is provided on the surface of the hard material 13. Therefore, even if the surface accuracy of the pressure plate 111 is not good, it can be directly absorbed by the hard material 13. Therefore, it is possible to arrange the elastic material 14 that forms the contact surface with the element array 40 in a state close to parallel to the horizontal plane, and the contact (degree of parallelism, etc.) between the surface of the element array 40, etc. and the pressure surface (contact surface with the element array 40) of the pressure unit 112 (elastic material 14) is good. Therefore, it is possible to apply pressure uniformly to the multiple elements 40a to 40c arranged on the mounting board 30, effectively preventing mounting defects, and the element array 40 can be stably manufactured on the mounting board 30.

A pressure applying device 210 according to the third embodiment shown in Fig. 5 has a similar configuration to the pressure applying device 110 according to the second embodiment, and exerts similar effects, except for the following points: In Fig. 5, the same reference numerals are used to designate the same members as those in the pressure applying device 110 according to the second embodiment, and some of the descriptions thereof will be omitted.

As shown in FIG. 5, the pressure device 210 has a pressure plate 211. The pressure plate 211 has a pressure section 212, which differs from the pressure section 112 in the second embodiment in that the pressure section 212 further has an elastic material 14 provided on the surface of the pressure plate 211. In this embodiment, the elastic material 14 is provided on the surface of the pressure plate 211, the hard material 13 is provided on the surface of the elastic material 14, and another elastic material 14 is provided on the surface of the hard material 13.

That is, in this embodiment, at least one hard material 13 (one in the illustrated example) and at least one elastic material 14 (two in the illustrated example) are alternately laminated on the surface of the pressure plate 211, and the pressure section 212 is composed of three layers of hard material 13 and elastic material 14. In the illustrated example, the elastic material 14 provided on the surface of the hard material 13 does not have the water-repellent layer 14a shown in FIG. 4, but in reality, the water-repellent layer 14a is provided.

In this embodiment, the hard material 13 is provided on the surface of the elastic material 14, and another elastic material 14 is provided on the surface of the hard material 13. Since the surface precision (e.g., flatness, smoothness, etc.) of the hard material 13 is higher than the surface precision (e.g., flatness, smoothness, etc.) of the pressure plate 211, by providing the hard material 13 between each elastic material 14, it is possible to arrange the outer elastic material 14 that constitutes the contact surface with the element array 40 in a state close to parallel to the horizontal plane. Therefore, the contact (degree of parallelism, etc.) between the surface of the element array 40, etc. and the pressure surface (contact surface with the element array 40) of the pressure unit 212 (outer elastic material 14) is improved, and it is possible to apply pressure uniformly to the multiple elements 40a to 40c arranged on the mounting board 30. Therefore, mounting defects can be effectively prevented, and the element array 40 can be stably manufactured on the mounting board 30.

In addition, as the elastic material 14 provided on the surface of the pressure plate 211 deforms, the surface of the element array 40, etc. and the surface of the outer elastic material 14 that forms the contact surface with the element array 40, etc. tend to become parallel, allowing more uniform pressure to be applied to the multiple elements 40a to 40c that make up the element array 40.

In addition, in this embodiment, at least one hard material 13 and at least one elastic material 14 are alternately laminated on the surface of the pressure plate 211. This makes it possible to achieve both the aforementioned effect obtained by providing the pressure plate 11 with the elastic material 14 (the effect obtained in the first embodiment) and the aforementioned effect obtained by providing the pressure plate 111 with the hard material 13 (the effect obtained in the second embodiment), and pressure can be applied more uniformly to the multiple elements 40a to 40c arranged on the mounting board 30.

A pressure applying device 310 according to the fourth embodiment shown in Fig. 6 has a similar configuration to the pressure applying device 210 according to the third embodiment, and exerts similar effects, except for the following points: In Fig. 6, the same reference numerals are used to designate the same members as those in the pressure applying device 210 according to the third embodiment, and some of the descriptions thereof will be omitted.

As shown in FIG. 6, the pressure device 310 has a pressure plate 311. The pressure plate 311 has a pressure section 312, which differs from the pressure section 212 in the third embodiment in that the pressure section 312 further has an elastic material 15 in addition to the hard material 13 and the elastic material 14. The elastic material 15 is provided on the surface of the hard material 13.

The elastic material 15 has a different shape from the elastic material 14, and its width in the X-axis direction and/or its width in the Y-axis direction is smaller than that of the elastic material 14. The elastic material 15 is also thicker than that of the elastic material 14. The material constituting the elastic material 15 may be the same as that of the elastic material 14, or may be different. In the illustrated example, the elastic material 15 does not have a water-repellent layer (a water-repellent layer corresponding to the water-repellent layer 14a shown in FIG. 1), but in reality, a water-repellent layer is provided.

In this way, the same effect as in the third embodiment can be obtained even when an elastic material 15 having a different shape and material from the elastic material 14 is provided on the surface of the hard material 13.

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1
1, a sample of a mounting substrate 30 on which elements 40a to 40c are arranged is prepared, and an elastic material 14 is provided on the surface of a pressure plate 11 of a pressure device 10. A carbon sheet is used as the elastic material 14. The thickness L1 of the elastic material 14 is 5 μm, the thickness L2 of the elements 40a to 40c is 8 μm (element thickness: 5 μm/electrode thickness: 3 μm), and the ratio L1/L2 of the thickness L1 of the elastic material 14 to the thickness (height) L2 of the elements 40a to 40c is 1.60.

A water-repellent layer 14a made of a water-repellent coating agent with a thickness of 0.05 μm was formed on the surface of the elastic material 14 (the surface on one side of the elastic material 14 where the elements 40a to 40c are located).

Ten identical samples were made, and each sample was pressed with a pressure plate 11 with an elastic material 14 on its surface. The surface of the mounting board 30 was then observed and evaluated for the presence or absence of mounting defects. If no mounting defects were observed at all among the ten samples, they were rated as GOOD, and if even the slightest mounting defect was observed, they were rated as NG. The results are shown in Table 1.

Examples 2 to 3, Comparative Examples 1 to 2
The thickness L1 of the elastic material 14 provided on the surface of the pressure plate 11 was changed from that of Example 1, and the ratio L1/L2 of the thickness L1 of the elastic material 14 to the thickness (height) L2 of the elements 40a to 40c was changed, and evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

As shown in Evaluation Table 1, it was confirmed that when the ratio L1/L2 of the thickness L1 of the elastic material 14 to the thickness (height) L2 of the elements 40a to 40c is within the range of 0.5 to 2.0, no mounting defects occur and the element array 40 can be stably manufactured on the mounting substrate 30.

The present invention is not limited to the above-described embodiment, and can be modified in various ways within the scope of the present invention.

In the first embodiment, micro LEDs are exemplified as the elements 40a to 40c mounted on the mounting substrate 30, but elements other than micro LEDs may be mounted on the mounting substrate 30. For example, the elements 40a to 40c are components used in electronic circuits, and may be chips such as MEMS, semiconductor elements, resistors, and capacitors. Semiconductor elements include discrete semiconductors such as transistors, diodes, LEDs, and thyristors, or integrated circuits such as ICs and LSIs. LEDs include mini LEDs, etc. When such elements are used, the thickness (height) of the elements 40a to 40c is preferably 100 μm or less, and more preferably 50 μm or less. The same applies to the second to fourth embodiments.

In the first embodiment, the surface of the elastic material 14 or the surface of the water-repellent layer 14a may have smaller irregularities (surface roughness Ra: 0.1 to 1.0 μm) than those that may be formed on the surface of the pressure plate 11. In this case, too, it is possible to prevent the elements 40a to 40c from adhering to the surface of the pressure section 12 (elastic material 14) when pressure is applied by the pressure plate 11, and it is possible to effectively prevent mounting defects from occurring. The same applies to the second and third embodiments. Also, in the fourth embodiment, similar irregularities may be formed on the surface of the elastic material 15 or the surface of the water-repellent layer provided on the elastic material 15.

In the first embodiment, the water-repellent layer 14a was provided only on one side of the elastic material 14 (the side on which the elements 40a to 40c are located), but it may also be provided on the opposite side. The same applies to the second and third embodiments.

In the second embodiment, a water-repellent layer may also be provided on the surface (both sides or one side) of the hard material 13. The same applies to the third and fourth embodiments. In this case, the thickness of the water-repellent layer is preferably 8 μm or less.

In the third embodiment described above, if the pressure applying section 212 is provided with multiple hard materials 13 and/or elastic materials 14, a water-repellent layer may be provided on the surface (both sides or one side) of each hard material 13 and each elastic material 14.

In the third embodiment, the pressure applying section 212 is provided with one hard material 13 and two elastic materials 14, but the number of hard materials 13 and elastic materials 14 provided in the pressure applying section 212 is not limited to this and may be greater. For example, the pressure applying section 212 may be provided with two hard materials 13 and three elastic materials 14.

In the third embodiment, a hard material 13 may be provided on the surface of the pressure plate 211, an elastic material 14 may be provided on the surface of the hard material 13, another hard material 13 may be provided on the surface of the elastic material 14, and yet another elastic material 14 may be provided on the surface of the hard material 13. In this case, the pressure unit 212 may further be provided with a hard material 13 and an elastic material 14.

In the fourth embodiment, the shape of the elastic material 15 is not limited to the illustrated example, and may be changed as appropriate. The arrangement of the elastic material 14 and the elastic material 15 may be interchanged. The technology shown in the third embodiment may be applied to the pressure device 310 of the fourth embodiment, and at least one hard material 13, at least one elastic material 14, and at least one elastic material 15 may be alternately laminated on the surface of the pressure plate 311.

In the first embodiment, the mounting support substrate 32 may be omitted. The same applies to the second to fourth embodiments.

In the first embodiment, the elements 40a to 40c are mounted on the mounting substrate 30 by heat and pressure bonding, but the elements 40a to 40c may be mounted on the mounting substrate 30 by solid-state bonding, anodic bonding, or other methods. The same applies to the second to fourth embodiments.

DESCRIPTION OF SYMBOLS 10,110,210,310...Pressure device 11,111,211,311...Pressure plate 12,112,212,312...Pressure section 13...Hard material 14,15...Elastic material 20...Mounting table 30...Mounting board 31_1,31_2...Wiring pattern 32...Mounting support board 40...Element array 40a,40b,40c...Element 41_1,41_2...Electrode 60...Transport device 61...Stamp tool 70...Supply table 80...Supply board 81...Board body 82...Adhesive layer 91...Control section 92...Pressure control mechanism 93...Drive mechanism 94...Heating mechanism 95...Temperature control mechanism

Claims (9)

a pressure plate having a pressure section for applying pressure to an element array made up of a plurality of elements arranged on a mounting substrate;
the pressure applying portion includes a plate-shaped elastic material and a plate-shaped hard material having a surface precision higher than that of the surface of the pressure plate,
The thickness of the elastic material is 0.5 to 2.0 times the thickness of the element;
The surface roughness of the hard material is 0.1 μm to 2.0 μm;
The hard material is bonded to a surface of the pressure plate,
The elastic material is bonded to a surface of the hard material, forming a pressure surface for applying pressure to the element array. The pressure device according to claim 1, wherein at least one of the hard materials and at least one of the elastic materials are further laminated alternately on the surface of the pressure plate. The pressure device for an element array according to claim 1 or 2, wherein a water-repellent layer that has been treated to make the elastic material water-repellent is formed on the surface of the elastic material. The pressure device for an element array according to claim 3, wherein the thickness of the water-repellent layer is smaller than the thickness of the elastic material. The pressure device according to any one of claims 1 to 4, wherein the thickness of the element is 50 μm or less. An element array manufacturing apparatus having a pressure device according to any one of claims 1 to 5. a mounting table on which the mounting substrate is placed;
a supply table on which a supply substrate having a plurality of the elements arranged thereon is placed;
a transport device that moves to the supply table to pick up the plurality of elements from the supply substrate and that moves to the mounting table to transfer the plurality of elements that have been picked up to the mounting substrate,
7. The device for manufacturing an element array according to claim 6, wherein the pressure plate applies pressure to the element array made up of a plurality of the elements transferred to the mounting substrate by the transfer device. preparing a mounting substrate on which a plurality of elements are arranged;
a step of applying pressure to an element array made up of a plurality of the elements arranged on the mounting board using a pressure device provided with a plate-shaped elastic material having a thickness 0.5 to 2.0 times that of the element and a plate-shaped hard material having a higher surface accuracy than the surface of a pressure plate;
The surface roughness of the hard material is 0.1 μm to 2.0 μm;
The hard material is bonded to a surface of the pressure plate,
The elastic material is bonded to a surface of the hard material, forming a pressure surface for applying pressure to the element array. The method for manufacturing an element array according to claim 8 , wherein the elements are connected to the mounting substrate by applying pressure to the elements against a conductive bonding material provided on the mounting substrate.

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