Connection structure and method for manufacturing the same

Abstract

To provide a method for manufacturing a connection structure capable of obtaining excellent conductivity of a chip component by irradiation with laser light, and a connection film.SOLUTION: A method for manufacturing a connection structure includes: a landing step of causing a chip component provided on a base material having permeability to a laser beam and a wiring substrate to face each other and irradiating the chip component with the laser beam from a base material side to land the chip component on the wiring substrate side; and a connection step of connecting the chip component and the wiring substrate via a connection film. The connection film includes a rubber layer and an adhesive layer. The rubber layer is broken through in the connection step.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present technology relates to a method for manufacturing a connection structure for connecting chip components to a substrate, and to a connection structure.

Background Art

[0002] In recent years, the development of micro-LEDs as next-generation displays for LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode) has been active. As an issue with micro-LEDs, a technique called mass transfer for mounting micro-sized LEDs on a panel substrate is required and is being studied everywhere.

[0003] As a currently mainstream method of mass transfer, there is a method of transferring LEDs to the panel substrate side using a stamp material. FIG. 11 is a diagram schematically showing the stamp method of mass transfer. In the stamp method, as shown in FIGS. 11A and 11B, the LED 101 is transferred from the transfer material 102 to the stamp material 103 and picked up, and as shown in FIGS. 11C and 11D, the LED 101 is pasted onto the connection film 105 of the panel substrate 104. However, the method using a stamp material has a problem that the pitch of the LEDs 101 depends on the pattern of the stamp material 103, resulting in low design freedom, low chip transfer rate, and very time-consuming, so it is not suitable for mass production.

[0004] Therefore, a chip placement method using a laser has currently attracted attention (see, for example, Patent Documents 1 to 4). FIG. 12 is a diagram schematically showing the laser method of mass transfer. In the laser method, as shown in FIGS. 12A and 12B, the LED 111 is transferred from the transfer material 112 to the release material 113 and picked up, and as shown in FIG. 12C, laser light is irradiated onto the release material 113 to land the LED 111 on the connection film 115 of the panel substrate 114. Chip transfer by the laser method has higher design freedom and a very fast chip transfer tact compared to the stamp material.

[0005] However, in the chip placement method using a laser, since the LED is bounced off and landed on the panel substrate side at a very high speed, for example, as shown in FIG. 12D, the LED may be displaced, deformed, detached, damaged, etc., resulting in defects. Also, even if the landing of the LED is good, there may be a conduction failure.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present technology has been proposed in view of such a conventional situation, and provides a method for manufacturing a connection structure and a connection structure capable of obtaining excellent conductivity of chip components by irradiation with laser light.

Means for Solving the Problems

[0008] The method for manufacturing a connection structure according to the present technology includes an impact step of facing a chip component provided on a base material having transparency to laser light and a wiring board, and irradiating the laser light from the base material side to land the chip component on the wiring board side, and a connection step of connecting the chip component and the wiring board via a connection film, wherein the connection film has a rubber layer and an adhesive layer, and in the connection step, the rubber layer is pierced.

[0009] In the manufacturing method of the connection structure, the rubber layer is pierced by the electrode of the chip component.

[0010] In the manufacturing method of the connection structure, the adhesive layer contains conductive particles, and the rubber layer is pierced by the conductive particles.

[0011] The connection structure according to the present technology includes a chip component, a wiring board, and a connection film provided between the electrode surface of the chip component and the electrode surface of the wiring board. The connection film is a cured film of a connection film having a rubber layer and an adhesive layer, and the rubber layer is pierced by the electrode of the chip component.

[0012] The connection structure according to the present technology includes a chip component, a wiring board, and a connection film provided between the electrode surface of the chip component and the electrode surface of the wiring board. The connection film is a cured film of a connection film having a rubber layer and an adhesive layer. The adhesive layer contains conductive particles, and the rubber layer is pierced by the conductive particles.

Advantages of the Invention

[0013] According to the present technology, when connecting the chip component and the wiring board, since the rubber layer of the connection film is pierced, excellent electrical conductivity of the chip component can be obtained.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present technology will be described in detail in the following order with reference to the drawings. 1. Manufacturing method of connection structure 2. Connection film 3. Examples

[0016] <1. Manufacturing method of connection structure> [First Embodiment] The manufacturing method of the connection structure according to the first embodiment includes a landing step of facing a chip component provided on a substrate having transparency to laser light and a wiring board, and irradiating laser light from the substrate side to land the chip component on the wiring board side, and a connection step of connecting the chip component and the wiring board via a connection film. The connection film has a rubber layer and an adhesive layer. In the landing step, the connection film is disposed on the electrode surface of the wiring board, and the rubber layer is made to collide with the electrode surface of the chip component. Thereby, in the landing step, the occurrence of defects such as displacement, deformation, breakage, and detachment of the chip component can be suppressed, and the chip component can be transferred and arranged with high precision and high efficiency. In the connection step, since the chip component breaks through the rubber layer and excellent conductivity can be obtained, the tact time can be shortened.

[0017] The adhesive layer in the connection film is preferably an anisotropic conductive adhesive layer containing conductive particles. Thereby, even when a connection site such as a eutectic type solder bump is not provided on the chip component, it becomes possible to connect the chip component and the wiring board. Further, when the electrode of the chip component becomes protruded or the like and an electrical connection with the wiring of the wiring board is obtained, the adhesive layer may not contain conductive particles.

[0018] Examples of the chip component include a semiconductor chip, an LED chip, etc., and it is not particularly limited. However, the manufacturing method of the connection structure according to the present technology can be suitably used for mass transfer of a large number of micro-sized LED chips onto a panel substrate which is a wiring board.

[0019] Hereinafter, as a manufacturing method of the connection structure, a manufacturing method of a display device in which a plurality of light-emitting elements which are LED chips are arranged on a wiring board which is a panel substrate to form a light-emitting element array will be described.

[0020] As the light-emitting element, a so-called flip-chip type LED having a first conductivity type electrode and a second conductivity type electrode on one side can be used. The light-emitting elements are arranged on the substrate corresponding to each sub-pixel constituting one pixel to form a light-emitting element array. One pixel may be composed of, for example, three sub-pixels of R (red), G (green), and B (blue), or four sub-pixels of RGBW (white) or RGBY (yellow), or two sub-pixels of RG or GB.

[0021] As the arrangement method of the sub-pixels, for example, in the case of RGB, there are a stripe arrangement, a mosaic arrangement, a delta arrangement, and the like. The stripe arrangement is an arrangement in which RGB is arranged in a vertical stripe shape, and high definition can be achieved. The mosaic arrangement is an arrangement in which the same color of RGB is arranged obliquely, and a more natural image can be obtained than the stripe arrangement. The delta arrangement arranges RGB in a triangle, and each dot is shifted by half a pitch for each field, and a natural image display can be obtained.

[0022] Table 1 shows the estimated horizontal pitch between RGB, the estimated chip size, and the estimated electrode size with respect to PPI (Pixels Per Inch) when each chip of RGB is arranged horizontally. The distance between chips is assumed to be at least 5 μm, and the estimated distance between RGB is maximized when arranged at equal intervals. This is calculated as a reference value for clarifying the application and examining this technology.

[0023]

Table 1

[0024] As shown in Table 1, it can be seen that by setting the chip size to 10×20 μm, it is possible to support up to 500 PPI. Also, by setting the chip size to 7×14 μm, it is possible to support up to 1000 PPI, and by further reducing the chip size, it is possible to achieve 1000 PPI or more. Note that the chip does not necessarily have to be rectangular and may be square.

[0025] Hereinafter, with reference to FIGS. 1 to 4, a landing step (A1) of irradiating a laser beam to land a light-emitting element on the wiring board side and a connecting step (B1) of connecting the light-emitting element and the wiring board will be described.

[0026] [Landing Step (A1)] FIG. 1 is a cross-sectional view schematically showing a state in which a light-emitting element provided on a base material and a connection film on a wiring board are opposed to each other, and FIG. 2 is an enlarged view showing the opposed light-emitting element and the connection film on the wiring board. As shown in FIGS. 1 and 2, first, in the landing step (A1), the chip component substrate 10 and the wiring board 30 are opposed to each other.

[0027] The chip component substrate 10 includes a base material 11, a release material 12, and a light-emitting element 20, and the light-emitting element 20 is attached to the surface of the release material 12. The base material 11 may have transparency to laser light, and among them, it is preferably quartz glass having a high light transmittance over the entire wavelength.

[0028] The release material 12 only needs to have absorption characteristics with respect to the wavelength of the laser beam, generates a shock wave by irradiation with the laser beam, and ejects the light-emitting element 20 toward the wiring board 30 side. Examples of the release material 12 include polyimide. The thickness T12 of the release material 12 is, for example, 0.5 μm or more.

[0029] The light-emitting element 20 includes a main body 21, a first conductivity type electrode 22, and a second conductivity type electrode 23, and has a horizontal structure in which the first conductivity type electrode 22 and the second conductivity type electrode 23 are arranged on the same surface side. The main body 21 includes, for example, a first conductivity type clad layer made of n-GaN, and, for example, In x Al y Ga 1-x-yIt includes an active layer composed of N layers and a second-conductivity-type clad layer made of, for example, p-GaN, and has a so-called double hetero structure. The first-conductivity-type electrode 22 is formed on a part of the first-conductivity-type clad layer by a passivation layer, and the second-conductivity-type electrode 23 is formed on a part of the second-conductivity-type clad layer. When a voltage is applied between the first-conductivity-type electrode 22 and the second-conductivity-type electrode 23, carriers are concentrated in the active layer and recombine to generate light emission.

[0030] The width W20 of the light-emitting element 20 is, for example, 1 to 100 μm, and the thickness T20 of the light-emitting element 20 is, for example, 1 to 20 μm.

[0031] The wiring substrate 30 includes a first-conductivity-type circuit pattern and a second-conductivity-type circuit pattern on a substrate 31, and has a first electrode 32 and a second electrode 33 at positions corresponding to, for example, the first-conductivity-type electrode on the p side and the second-conductivity-type electrode on the n side so that the light-emitting elements are arranged in units of sub-pixels (sub-pixels) each constituting one pixel. Further, the wiring substrate 30 forms circuit patterns such as data lines and address lines of, for example, matrix wiring, and enables the light-emitting elements corresponding to each sub-pixel constituting one pixel to be turned on and off. Further, the wiring substrate 30 is preferably a light-transmitting substrate, the substrate 31 is preferably a transparent substrate such as glass, PET (Polyethylene Terephthalate), or polyimide, and the circuit pattern, the first electrode 32, and the second electrode 33 are preferably transparent conductive films such as ITO (Indium-Tin-Oxide), IZO (Indium-Zinc-Oxide), ZnO (Zinc-Oxide), or IGZO (Indium-Gallium-Zinc-Oxide).

[0032] As described below, the connection film 40 has a rubber layer 41 and an anisotropic conductive adhesive layer 42, and is attached onto the wiring substrate 30 with the rubber layer 41 side facing the light-emitting element 20. The rubber layer 41 is preferably at least one selected from silicone rubber and acrylic rubber. The thickness of the rubber layer 41 is preferably 0.5 μm or more and 3.0 μm or less, more preferably 0.5 μm or more and 2.0 μm or less, and still more preferably 0.5 μm or more and 1.5 μm or less. Further, the rubber layer 41 preferably has voids inside, and is preferably in a shape such as a net shape or a protrusion shape. Thereby, cushioning properties can be improved in the landing process, and the breakthrough resistance of the light-emitting element 20 can be improved in the connection process. The anisotropic conductive adhesive layer 42 preferably contains conductive particles 43 in a thermosetting binder.

[0033] The thickness T40 of the connection film 40 is, for example, 20 μm or less. Also, the distance D between the light-emitting element 20 and the connection film 40 is preferably 10 to 1000 μm, more preferably 50 to 500 μm, and still more preferably 80 to 200 μm.

[0034] FIG. 3 is a cross-sectional view schematically showing a state in which laser light is irradiated from the substrate side, and the light-emitting elements are transferred and arranged at predetermined positions on the wiring substrate. As shown in FIGS. 2 and 3, in the landing process (A1), laser light 50 is irradiated from the substrate 11 side, the light-emitting elements 20 are transferred to predetermined positions on the wiring substrate 21, and arranged on the connection film 40.

[0035] For the transfer of the light-emitting element 20, for example, a lift (LIFT: Laser Induced Forward Transfer) device can be used. The lift device includes, for example, a telescope that collimates the pulsed laser light emitted from a laser device, a shaping optical system that uniformly shapes the spatial intensity distribution of the pulsed laser light that has passed through the telescope, a mask that allows the pulsed laser light shaped by the shaping optical system to pass through in a predetermined pattern, a field lens located between the shaping optical system and the mask, and a projection lens that reduces and projects the laser light that has passed through the pattern of the mask onto the donor substrate. The chip component substrate 10, which is the donor substrate, is held on a donor stage, and the wiring substrate 30, which is the receptor substrate, is held on a receptor stage.

[0036] As the laser device, for example, an excimer laser that oscillates laser light with a wavelength of 180 nm to 360 nm can be used. The oscillation wavelength of the excimer laser is, for example, 193, 248, 308, 351 nm, and these oscillation wavelengths can be suitably selected according to the light absorptivity of the material of Release 12.

[0037] The mask uses a pattern in which an array of windows of a predetermined size at a predetermined pitch is formed so that the projection at the interface between the base material 11 and the release material 12 becomes the desired array of laser light. The mask has a pattern applied to the base material 11 by, for example, chrome plating. The window portions without chrome plating transmit the laser light, and the portions with chrome plating block the laser light.

[0038] The light emitted from the laser device is incident on the telescope optical system and propagates to the shaping optical system ahead. The laser light immediately before entering the shaping optical system is adjusted by the telescope optical system so as to be substantially parallel light at any position within the movement range of the X axis of this donor stage. Therefore, it always enters the shaping optical system at substantially the same size and the same angle (perpendicular).

[0039] The laser light that has passed through the shaping optical system is incident on the mask through a field lens that constitutes an image-side telecentric reduction projection optical system in combination with a projection lens. The laser light that has passed through the mask pattern has its propagation direction changed vertically downward by an epi-mirror and is incident on the projection lens. The laser light emitted from the projection lens is incident from the side of the base material 11 and is accurately projected onto a predetermined position of the release material 12 formed on its surface (lower surface) at the reduced size of the mask pattern.

[0040] The pulse energy of the laser light that is imaged and irradiated onto the interface between the base material 11 and the release material 12 is preferably 0.001 to 2 J, more preferably 0.01 to 1.5 J, and even more preferably 0.1 to 1 J. The fluence is preferably 0.001 to 2 J / cm 2 and more preferably 0.01 to 1 J / cm 2 and even more preferably 0.05 to 0.5 J / cm 2 The pulse width (irradiation time) is preferably 0.01 to 1×10 9 picoseconds, more preferably 0.1 to 1×10 7 picoseconds, and even more preferably 1 to 1×10 5 picoseconds. The pulse frequency is preferably 0.1 to 10,000 Hz, more preferably 1 to 1,000 Hz, and even more preferably 1 to 100 Hz. The number of irradiation pulses is preferably 1 to 30,000,000.

[0041] By using such a lift device, a shock wave is generated in the release material 12 irradiated with the laser light at the interface between the base material 11 and the release material 12, and a plurality of light-emitting elements 20 are peeled off from the base material 11 and lifted toward the wiring board 30, and the plurality of light-emitting elements 20 can be landed on a predetermined position of the wiring board 30 via a connection film 40.

[0042] Since the connection film 40 has a rubber layer 41 on the side of the plurality of light-emitting elements 20, it can alleviate the impact when the light-emitting elements 20 launched at ultra-high speed land, suppress the occurrence of defects such as displacement, deformation, breakage, and detachment of the light-emitting elements 20, and obtain a high landing success rate.

[0043] [Connection Step (B1)] FIG. 4 is a cross-sectional view schematically showing a state where a light-emitting element is mounted on a wiring board. As shown in FIG. 4, in the connection step (B1), the light-emitting elements 20 arranged at predetermined positions on the wiring board 30 are mounted.

[0044] As a method of thermocompression bonding the light-emitting element 20 to the wiring board 30, a connection method used in a known anisotropic conductive film can be appropriately selected and used. As the thermocompression bonding conditions, for example, the temperature is 150°C to 260°C, the pressure is 5 MPa to 60 MPa, and the time is 5 seconds to 300 seconds.

[0045] The rubber layer 41 of the connection film 40 is pierced by the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 during thermocompression bonding. Then, the conductive particles 43 of the anisotropic conductive adhesive layer 42 are sandwiched between the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 and the first electrode 32 and the second electrode 33 of the wiring board 30, and the anisotropic conductive film is formed by the hardening of the binder of the anisotropic conductive adhesive layer 42.

[0046] According to the manufacturing method of the connection structure according to the first embodiment, by arranging a connection film having a rubber layer and an adhesive layer on the electrode surface of the wiring board and colliding the rubber layer with the electrode surface of the chip component, in the landing step, the occurrence of defects such as displacement, deformation, breakage, and detachment of the chip component can be suppressed, and the chip component can be transferred and arranged with high precision and high efficiency. In the connection step, the chip component can break through the rubber layer and excellent electrical conductivity can be obtained.

[0047] In the first embodiment, the connection film was attached to the entire surface of the wiring board. However, for example, using a mass transfer technique, individual pieces of the connection film may be transferred to the electrode positions on the wiring board. Instead of attaching the connection film to the entire surface, by selectively attaching it only to the positions where the chip components are skipped, for example, the transparency of the light-emitting element array can be improved.

[0048] [Second Embodiment] In the first embodiment, the connection film having a rubber layer and an adhesive layer was disposed on the wiring board. However, the rubber layer may be disposed on the electrode surface of the chip component, and the adhesive layer may be disposed on the wiring board.

[0049] That is, the method for manufacturing a connection structure according to the second embodiment includes an landing step of facing a chip component provided on a base material having transparency to laser light and a wiring board, and irradiating laser light from the base material side to land the chip component on the wiring board side, and a connection step of connecting the chip component and the wiring board via a connection film. The connection film has an adhesive layer, the chip component has a rubber layer on the electrode surface, and in the landing step, the connection film is disposed on the electrode surface of the wiring board, and the adhesive layer and the rubber layer of the chip component are made to collide.

[0050] Hereinafter, in the same manner as in the first embodiment, as a method for manufacturing a connection structure, the landing step (A2) and the connection step (B2) in a method for manufacturing a display device in which a plurality of light-emitting elements, which are LED chips, are arranged on a wiring board, which is a panel substrate, to form a light-emitting element array will be described. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0051] [Landing Step (A2)] FIG. 5 is a cross-sectional view schematically showing a state in which a light-emitting element provided on a base material and having a rubber layer on the electrode surface is opposed to an anisotropic conductive adhesive layer on a wiring board. As shown in FIG. 5, first, in the landing step (A2), the chip component substrate 10 and the wiring board 30 are opposed to each other.

[0052] The chip component substrate 10 includes a base material 11, a release material 12, and a light-emitting element 20, and the light-emitting element 20 is attached to the surface of the release material 12. Also, a rubber layer 51 is attached to the electrode surface of the light-emitting element 20. Since the rubber layer 51 is the same as the rubber layer 41 in the first embodiment, the description thereof is omitted.

[0053] The connection film 50 is composed of an anisotropic conductive adhesive layer 52 and is attached to positions on the first electrode 32 and the second electrode 33 of the wiring substrate 30. Since the anisotropic conductive adhesive layer 22 is the same as the anisotropic conductive adhesive layer 42 in the first embodiment, the description thereof is omitted.

[0054] In the landing process (A2), the rubber layer 51 attached to the light-emitting element 20 alleviates the impact when the light-emitting element 20 ejected at ultra-high speed lands on the anisotropic conductive adhesive layer 52, suppresses the occurrence of defects such as displacement, deformation, breakage, and detachment of the light-emitting element 20, and a high landing success rate can be obtained.

[0055] [Connection process (B2)] In the connection process (B2), the light-emitting elements 20 arranged at predetermined positions on the wiring substrate 30 are mounted. The method of thermocompression bonding the light-emitting elements 20 to the wiring substrate 30 is the same as that in the first embodiment. The rubber layer 51 attached to the light-emitting element 20 is pierced by the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 during thermocompression bonding. Then, the conductive particles 53 of the anisotropic conductive adhesive layer 52 are sandwiched between the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 and the first electrode 32 and the second electrode 33 of the wiring substrate 30, and an anisotropic conductive film is formed by curing the binder of the anisotropic conductive adhesive layer 52.

[0056] According to the manufacturing method of the connection structure according to the second embodiment, a rubber layer is disposed on the electrode surface of the chip component, a connection film made of an adhesive layer is disposed on the electrode surface of the wiring board, and the rubber layer and the connection film are made to collide. Thus, in the landing process, the occurrence of defects such as displacement, deformation, breakage, and detachment of the chip component can be suppressed, and the chip component can be transferred and arranged with high precision and high efficiency. In the connection process, the chip component can break through the rubber layer and excellent electrical conductivity can be obtained.

[0057] [Third Embodiment] In the first embodiment, the connection film having the rubber layer and the adhesive layer is disposed on the wiring board, but the connection film may be disposed on the electrode surface of the chip component.

[0058] That is, the manufacturing method of the connection structure according to the third embodiment includes a landing process of facing a chip component provided on a base material having transparency to laser light and a wiring board, and irradiating laser light from the base material side to land the chip component on the wiring board side, and a connection process of connecting the chip component and the wiring board via a connection film. The connection film has a rubber layer and an adhesive layer. In the landing process, the connection film is disposed on the electrode surface of the chip component, and the rubber layer is made to collide with the electrode surface of the wiring board.

[0059] Hereinafter, in the same manner as in the first embodiment, in the manufacturing method of the connection structure, the landing process (A3) and the connection process (B3) in the manufacturing method of a display device in which a plurality of light emitting elements, which are LED chips, are arranged on a wiring board, which is a panel substrate, to form a light emitting element array will be described. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0060] [Landing Process (A3)] FIG. 6 is a cross-sectional view schematically showing a state in which a light emitting element provided on a base material and having a connection film on an electrode surface and a wiring board are opposed to each other. As shown in FIG. 6, first, in the landing process (A2), the chip component substrate 10 and the wiring board 30 are opposed to each other.

[0061] The chip component substrate 10 includes a base material 11, a release material 12, and a light-emitting element 20, and the light-emitting element 20 is attached to the surface of the release material 12. Also, a connection film 60 is attached to the electrode surface of the light-emitting element 20.

[0062] The connection film 60 has a rubber layer 61 and an anisotropic conductive adhesive layer 62, and the rubber layer 61 side faces the wiring substrate 30. Since the rubber layer 61 and the anisotropic conductive adhesive layer 62 are the same as the rubber layer 41 and the anisotropic conductive adhesive layer 42 in the first embodiment, the description thereof is omitted.

[0063] In the landing step (A3), the rubber layer 61 to which the light-emitting element 20 is attached alleviates the impact when the light-emitting element 20 ejected at ultra-high speed lands on the electrode surface of the wiring substrate 30, suppresses the occurrence of defects such as displacement, deformation, breakage, and detachment of the light-emitting element 20, and a high landing success rate can be obtained.

[0064] [Connection step (B3)] In the connection step (B3), the light-emitting elements 20 arranged at predetermined positions on the wiring substrate 30 are mounted. The method of thermocompression bonding the light-emitting element 20 to the wiring substrate 30 is the same as in the first embodiment. The rubber layer 61 attached to the light-emitting element 20 is pierced by the conductive particles 63 of the anisotropic conductive adhesive layer 62 during thermocompression bonding. Then, the conductive particles 63 of the anisotropic conductive adhesive layer 62 are sandwiched between the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 and the first electrode 32 and the second electrode 33 of the wiring substrate 30, and an anisotropic conductive film is formed by curing the binder of the anisotropic conductive adhesive layer 62.

[0065] According to the manufacturing method of the connection structure according to the third embodiment, by arranging a connection film having a rubber layer and an adhesive layer on the electrode surface of the chip component and colliding the rubber layer with the electrode surface of the wiring substrate, in the landing step, the occurrence of defects such as displacement, deformation, breakage, and detachment of the chip component can be suppressed, and the chip component can be transferred and arranged with high precision and high efficiency. In the connection step, excellent conductivity can be obtained.

[0066] [Fourth Embodiment] In the first embodiment, the connection film having the rubber layer and the adhesive layer is disposed on the wiring board. However, the adhesive layer may be disposed on the electrode surface of the chip component, and the rubber layer may be disposed on the wiring board.

[0067] That is, the manufacturing method of the connection structure according to the fourth embodiment includes: facing a chip component provided on a base material having transparency to laser light and a wiring board, and irradiating laser light from the base material side to land the chip component on the wiring board side; and a connecting step of connecting the chip component and the wiring board via a connection film. The connection film has an adhesive layer, the wiring board has a rubber layer on the electrode surface, and in the landing step, the connection film is disposed on the electrode surface of the chip component, and the adhesive layer and the rubber layer of the wiring board are made to collide with each other.

[0068] Hereinafter, in the same manner as in the first embodiment, the landing step (A4) and the connecting step (B4) in the manufacturing method of a display device that forms a light emitting element array by arranging a plurality of light emitting elements, which are LED chips, on a wiring board, which is a panel substrate, as the manufacturing method of the connection structure will be described. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0069] [Landing Step (A4)] FIG. 7 is a cross-sectional view schematically showing a state in which a light emitting element provided on a base material and having an anisotropic conductive adhesive layer on an electrode surface faces a rubber layer on a wiring board. As shown in FIG. 7, first, in the landing step (A4), the chip component substrate 10 and the wiring board 30 are opposed to each other.

[0070] The chip component substrate 10 includes a base material 11, a release material 12, and a light emitting element 20, and the light emitting element 20 is attached to the surface of the release material 12. A connection film 70 made of an anisotropic conductive adhesive layer 72 is attached to the electrode surface of the light emitting element 20. Since the anisotropic conductive adhesive layer 72 is the same as the anisotropic conductive adhesive layer 42 in the first embodiment, the description thereof will be omitted.

[0071] Also, a rubber layer 71 is attached to positions on the first electrode 32 and the second electrode 33 of the wiring board 30. Since the rubber layer 71 is the same as the rubber layer 41 in the first embodiment, the description thereof is omitted.

[0072] In the landing step (A4), the rubber layer 71 attached to the wiring board 30 alleviates the impact when the light-emitting element 20 ejected at ultra-high speed lands, suppresses the occurrence of defects such as displacement, deformation, breakage, and detachment of the light-emitting element 20, and can obtain a high landing success rate.

[0073] [Connection step (B4)] In the connection step (B4), the light-emitting elements 20 arranged at predetermined positions on the wiring board 30 are mounted. The method of thermocompression bonding the light-emitting element 20 to the wiring board 30 is the same as that in the first embodiment. The rubber layer 71 attached to the wiring board 30 is pierced by the conductive particles 73 of the anisotropic conductive adhesive layer 72 during thermocompression bonding. Then, the conductive particles 73 of the anisotropic conductive adhesive layer 72 are sandwiched between the first conductive type electrode 22 and the second conductive type electrode 23 of the light-emitting element 20 and the first electrode 32 and the second electrode 33 of the wiring board 30, and an anisotropic conductive film is formed by curing the binder of the anisotropic conductive adhesive layer 72.

[0074] According to the manufacturing method of the connection structure according to the fourth embodiment, a connection film made of an adhesive layer is arranged on the electrode surface of the chip component, a rubber layer is arranged on the electrode surface of the wiring board, and the adhesive layer and the rubber layer are collided with each other, so that in the landing step, the occurrence of defects such as displacement, deformation, breakage, and detachment of the chip component can be suppressed, the chip component can be transferred and arranged with high precision and high efficiency, and excellent conductivity can be obtained in the connection step.

[0075] <2. Connection film> The connection film according to the present embodiment has a rubber layer and an adhesive layer, and the thickness of the rubber layer is 0.5 μm or more and 3.0 μm or less. Thereby, for example, when landing a chip component on a wiring board using laser light-based mass transfer, the landing rate can be improved, and excellent conductivity can be obtained.

[0076] The subsequent layer is preferably an anisotropic conductive adhesive layer containing conductive particles. Thereby, even when the chip component is not provided with a connection site such as a solder bump, it becomes possible to connect the chip component and the wiring board. Further, the anisotropic conductive adhesive layer is preferably configured by aligning the conductive particles in a direction, and it is preferable to unevenly distribute the conductive particles on the wiring board side in the thickness direction. Thereby, the capturability of the conductive particles between the electrode of the chip component and the electrode of the wiring board can be improved. Note that when the electrode of the chip component is protruded or the like and electrical connection with the wiring of the wiring board is obtained, the adhesive layer may not contain conductive particles.

[0077] FIG. 8 is a cross-sectional view schematically showing a first configuration example of the connection film. As shown in FIG. 8, the connection film 40 has a rubber layer 41 and an anisotropic conductive adhesive layer 42 containing conductive particles 43.

[0078] The rubber layer 41 is not particularly limited as long as it is an elastomer having high cushioning properties (shock absorption properties). Specific examples include, for example, silicone rubber, acrylic rubber, butadiene rubber, polyurethane resin (urethane-based elastomer), and the like. Among these, the rubber layer 41 is preferably one or more selected from silicone rubber and acrylic rubber.

[0079] The thickness of the rubber layer 41 is preferably 0.5 μm or more and 3.0 μm or less, more preferably 0.5 μm or more and 2.0 μm or less, and still more preferably 0.5 μm or more and 1.5 μm or less. If the thickness of the rubber layer 41 is too small, it tends to be difficult to obtain shock absorption properties, and if the thickness of the rubber layer 41 is too small, it tends to be difficult to obtain conductivity.

[0080] The durometer A hardness of the rubber layer 41 is preferably 20 to 40, more preferably 20 to 35, and even more preferably 20 to 30. When the durometer A hardness is too high, the rubber layer is too hard, and defects such as deformation and breakage of the chip component are likely to occur. When the durometer A hardness is too low, the rubber layer 41 is too soft, and defects such as displacement of the chip component are likely to occur. The durometer A hardness of the rubber layer 41 can be measured as rubber hardness (JIS-A hardness) using a durometer A in accordance with JIS K 6253.

[0081] The storage modulus of the rubber layer 41 at a temperature of 30°C and a frequency of 200 Hz in the dynamic viscoelasticity test using a push-in test device is preferably 60 MPa or less, more preferably 40 MPa or less, and even more preferably 30 MPa or less. When the storage modulus at a temperature of 30°C and a frequency of 200 Hz is too high, the impact of the chip component ejected at high speed by laser irradiation cannot be absorbed, and the transfer rate of the chip component tends to decrease. The storage modulus of the rubber layer 41 at a temperature of 30°C and a frequency of 200 Hz can be measured using a push-in test device, for example, using a flat punch with a diameter of 100 μm, setting the target push-in depth to 1 μm, and sweeping the range of frequencies from 1 to 200 Hz.

[0082] The anisotropic conductive adhesive layer 42 may be a so-called anisotropic conductive film (ACF: Anisotropic Conductive Film) containing conductive particles 43. As the conductive particles, those used in known anisotropic conductive films can be appropriately selected and used. Examples include metal particles such as nickel, copper, silver, gold, palladium, and solder, and metal-coated resin particles in which the surfaces of resin particles such as polyamide and polybenzoguanamine are coated with a metal such as nickel or gold. This enables conduction even when the chip component is not provided with a connection site such as a solder bump.

[0083] Further, it is preferable that the anisotropic conductive adhesive layer 42 is configured by aligning the conductive particles 43 in the plane direction. By configuring the conductive particles to be aligned in the plane direction, the particle surface density becomes uniform, and very excellent electrical conductivity can be obtained. Also, it is preferable that the anisotropic conductive adhesive layer 42 has the conductive particles 43 unevenly distributed on the side of the wiring substrate in the thickness direction. For example, in the aforementioned first embodiment, the conductive particles 43 in the anisotropic conductive adhesive layer 42 may be unevenly distributed on the side opposite to the surface of the rubber layer 41, and in the aforementioned third embodiment, the conductive particles 43 in the anisotropic conductive adhesive layer 42 may be unevenly distributed on the surface side of the rubber layer 41. Thereby, the capturing property of the conductive particles between the electrodes of the chip component and the electrodes of the wiring substrate can be improved.

[0084] The particle diameter of the conductive particles 43 is not particularly limited, but the lower limit of the particle diameter is preferably 1 μm or more, and the upper limit of the particle diameter is preferably, for example, 50 μm or less, more preferably 20 μm or less, from the viewpoint of the capturing efficiency of the conductive particles in the connection structure. Note that the particle diameter of the conductive particles can be a value measured by an image type particle size distribution meter (for example, FPIA-3000: manufactured by Malvern). The number is preferably 1000 or more, preferably 2000 or more. Also, the particle surface density of the conductive particles can be determined according to the electrode area of the chip component, etc., and can be, for example, in the range of 500 to 140000 pcs / mm 2 and can be in the range.

[0085] The anisotropic conductive adhesive layer 42 is preferably composed of a thermosetting binder containing a film-forming resin, a thermosetting resin, and a curing agent. The thermosetting binder is not particularly limited, and examples include a thermoanionic polymerization type resin composition containing an epoxy compound and a thermal anionic polymerization initiator, a thermocationic polymerization type resin composition containing an epoxy compound and a thermal cationic polymerization initiator, a thermal radical polymerization type resin composition containing a (meth)acrylate compound and a thermal radical polymerization initiator, and the like. Note that the (meth)acrylate compound means including both acrylic monomers (oligomers) and methacrylic monomers (oligomers).

[0086] Among these thermosetting binders, it is preferable that the thermosetting resin contains an epoxy compound and the curing agent is a thermal cationic polymerization initiator. Thereby, the curing reaction by laser light can be suppressed and rapid curing can be achieved by heat. Hereinafter, as a specific example, a thermally cationic polymerization type resin composition containing a film-forming resin, an epoxy compound, and a thermal cationic polymerization initiator will be described as an example.

[0087] The film-forming resin corresponds to, for example, a high molecular weight resin having an average molecular weight of 10,000 or more, and from the viewpoint of film-forming property, it preferably has an average molecular weight of about 10,000 to 80,000. Examples of the film-forming resin include various resins such as phenoxy resin, polyester resin, polyurethane resin, polyester urethane resin, acrylic resin, polyimide resin, and butyral resin. These may be used alone or in combination of two or more. Among these, it is preferable to use a phenoxy resin from the viewpoints of film-forming state, connection reliability, etc. The content of the film-forming resin in the anisotropic conductive adhesive layer is preferably 20 to 50 wt%, more preferably 25 to 45 wt%, and still more preferably 30 to 40 wt%.

[0088] The epoxy compound is not particularly limited as long as it is an epoxy compound having one or more epoxy groups in the molecule. For example, it may be a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, etc., or may be a urethane-modified epoxy resin. Among these, a high-purity bisphenol A type epoxy resin can be preferably used. Specific examples of the high-purity bisphenol A type epoxy resin include, for example, the product name "YL980" manufactured by Mitsubishi Chemical Corporation. The content of the epoxy compound in the anisotropic conductive adhesive layer is preferably 10 to 55 wt%, more preferably 15 to 50 wt%, and still more preferably 20 to 45 wt%.

[0089] As the thermal cationic polymerization initiator, those known as the thermal cationic polymerization initiator for epoxy compounds can be adopted. For example, those that generate an acid capable of cationically polymerizing a cationic polymerization type compound by heat, and known iodonium salts, sulfonium salts, phosphonium salts, ferrocenes, etc. can be used. Among these, aromatic sulfonium salts showing good latency with respect to temperature can be preferably used. As a specific example of the aromatic sulfonium salt-based polymerization initiator, for example, the product name "SI-60L" manufactured by Sanshin Chemical Industry Co., Ltd. can be cited. The content of the thermal cationic polymerization initiator in the anisotropic conductive adhesive layer is preferably 1 to 20 wt%, more preferably 2 to 15 wt%, and still more preferably 3 to 12 wt%.

[0090] In addition, as other additives to be blended with the thermosetting binder, an inorganic filler, a silane coupling agent, a diluting monomer, a filler, a softening agent, a coloring agent, a flame retardant, a thixotropic agent, etc. may be blended as necessary.

[0091] As the inorganic filler, silica, talc, titanium oxide, calcium carbonate, magnesium oxide, etc. can be used. The inorganic filler may be used alone or in combination of two or more. The content of the inorganic filler in the anisotropic conductive adhesive layer is preferably 1 to 30 wt%, more preferably 5 to 25 wt%, and still more preferably 10 to 20 wt%. When two or more inorganic fillers are used in combination, it is preferable that the total content of the inorganic fillers in the thermosetting binder is within the above-mentioned range.

[0092] The lower limit of the thickness of the anisotropic conductive adhesive layer 42 may be, for example, the same as the particle diameter of the conductive particles, and preferably may be 1.3 times or more the conductive particle diameter or 3 μm or more. Also, the upper limit of the thickness of the connection film can be, for example, 20 μm or less or 2 times or less the particle diameter of the conductive particles. Further, the connection film may have an adhesive layer or an adhesive layer that does not contain conductive particles laminated thereon, and the number of layers and the lamination surface thereof can be appropriately selected according to the object and purpose. Also, as the insulating resin of the adhesive layer or the adhesive layer, the same ones as those of the connection film can be used. The film thickness can be measured using a known micrometer or digital thickness gauge. The film thickness can be obtained, for example, by measuring 10 or more points and averaging them.

[0093] [Modification Example] In the first configuration example, the rubber layer preferably has voids inside and is preferably in a shape such as a net shape or a protrusion shape. Thereby, the shock absorbability is improved by the air layer, and the landing rate of the chip component can be improved. Also, when connecting the chip component, the chip component can easily break through the rubber layer, so that excellent conduction resistance can be obtained.

[0094] FIG. 9(A) is a plan view showing two rubber layers having voids inside by processing, and FIG. 9(B) is a cross-sectional view schematically showing a second configuration example of the connection film. As shown in FIG. 9, the connection film 80 as the second configuration example has a rubber layer 81 and an anisotropic conductive adhesive layer 82 containing conductive particles 83. The rubber layer 81 is formed by laminating a first rubber layer 81A and a second rubber layer 81B, and has, for example, a mesh shape (mesh type). The first rubber layer 81A and the second rubber layer 81B have a plurality of holes formed on the surface by curing the rubber using, for example, a plurality of convex molds. Also, the rubber layer 81 may be, for example, a porous layer instead of the mesh type. Note that, since the anisotropic conductive adhesive layer 82 is the same as the anisotropic conductive adhesive layer 42, the description thereof is omitted.

[0095] FIG. 10 is a cross-sectional view schematically showing a third configuration example of a connection film. As shown in FIG. 10, a connection film 90 as a third configuration example includes a rubber layer 91 and an anisotropic conductive adhesive layer 92 containing conductive particles 93. The rubber layer 91 has, for example, a protrusion shape (protrusion type), and a plurality of holes are formed on the surface by curing the rubber using, for example, a plurality of convex molds. Since the anisotropic conductive adhesive layer 92 is the same as the anisotropic conductive adhesive layer 42, the description thereof is omitted.

[0096] As in the modification example, since the rubber layer has voids inside, the shock absorbency is improved, and the landing rate of the chip component can be improved. In addition, the puncture resistance of the rubber layer is improved, and excellent conduction resistance can be obtained.

Example

[0097] <3. Example> In the example, a chip component provided on quartz glass and a connection film provided on a glass substrate were opposed to each other, and laser light was irradiated from the base material side to land the chip component on the connection film, and the landing property was evaluated. In addition, a connection structure was fabricated and the conductivity was evaluated. Note that the present technology is not limited to these examples.

[0098] [Fabrication of Anisotropic Conductive Adhesive Layer] The following materials were prepared. Phenoxy resin (trade name: PKHH, manufactured by Yaba Chemical Industry Co., Ltd.) High-purity bisphenol A type epoxy resin (trade name: YL-980, manufactured by Mitsubishi Chemical Corporation) Hydrophobic silica (trade name: RY200, manufactured by Nippon Aerosil Co., Ltd.) Cationic polymerization initiator (trade name: SI-60L, manufactured by Sanshin Chemical Industry Co., Ltd.) Conductive particles (average particle size 3 μm, resin core metal-coated fine particles, Ni plating thickness 0.2 μm, manufactured by Sekisui Chemical Co., Ltd.)

[0099] As shown in Table 2, each material was blended in a predetermined number of parts by mass, and an anisotropic conductive adhesive layer with a thickness of 6 μm was formed on a glass substrate with a thickness of 0.5 mm. The anisotropic conductive adhesive layer was formed, for example, by the method described in Japanese Patent No. 6187665, and conductive particles were aligned on one surface of the binder layer so that the particle surface density was 58000 pcs / mm 2

[0100]

Table 2

[0101] [Evaluation of Landing Elasticity of Chip Components] Using a pick-and-place device (MT-30C200), chip components provided on a quartz glass were landed on a connection film on a glass substrate. The chip components (outer dimensions: 30 × 50 μm, thickness: 5 μm, electrode thickness: 2 μm) were provided with a release material (polyimide) between the quartz glass and the chip components using a TEG (Test Element Group).

[0102] As described above, the pick-and-place device includes a telescope that collimates the pulsed laser light emitted from a laser device, a shaping optical system that uniformly shapes the spatial intensity distribution of the pulsed laser light that has passed through the telescope, a mask that allows the pulsed laser light shaped by the shaping optical system to pass through in a predetermined pattern, a field lens located between the shaping optical system and the mask, and a projection lens that reduces and projects the laser light that has passed through the pattern of the mask onto a donor substrate. The chip component, which is the donor substrate, is held on a donor stage with a quartz substrate held by a release material, the connection film, which is the receptor substrate, is held on a receptor stage with a glass substrate to which it is attached, and the distance between the chip component and the connection film is set to 100 μm.

[0103] The laser device used an excimer laser with an oscillation wavelength of 248 nm. The pulse energy of the laser light was 600 J, and the fluence was 150 J / cm 2 ​, the pulse width (irradiation time) was 30,000 picoseconds, the pulse frequency was 0.01 kHz, and the number of irradiation pulses was 1 pulse for each small piece of ACF1. The pulse energy of the laser light imaged and irradiated on the interface between the anisotropic conductive adhesive layer and the substrate was 0.001 - 2 J, and the fluence was 0.001 - 2 J / cm 2 and the pulse width (irradiation time) was 0.01 - 1×10 9 picoseconds, the pulse frequency was 0.1 - 10,000 Hz, and the number of irradiation pulses was 1 - 30,000,000.

[0104] As the mask, a pattern in which an array of windows of a predetermined size at a predetermined pitch was formed was used such that the projection at the interface between the quartz glass as the donor substrate and the release material was 30×50 μm of the outer shape of the chip component.

[0105] A total of 100 chip components were transferred onto the connection film, and the number of chip components that had landed normally on the connection film was counted using a microscope. It is desirable that the ratio of the chip components that have landed normally is 90% or more.

[0106] [Fabrication of the connection structure] The chip components were landed on the connection film of the wiring board and thermocompression bonded under the conditions of a temperature of 170°C - a pressure of 10 Mpa - a time of 30 sec to fabricate the connection structure. As the chip components (outer shape 50 μm×50 μm, thickness 150 μm), TEG (Test Element Group) provided with a pair of electrodes (Cr / Au-plated bump 12 μm×12 μm) on the chip components was used. As the wiring board, a glass substrate (thickness 0.5 mm, Ti / Al / Ti pattern 12 μm×12 μm) was used.

[0107] [Evaluation of conductivity] Using the conductive wiring on the wiring board side, the conduction resistance of the connection structure was measured. The evaluation of conductivity was determined as follows: A - D according to the resistance value. It is desirable that the determination is C or above. A: 50 Ω or less B: More than 50 Ω and 100 Ω or less C: More than 100 Ω and 200 Ω or less D: 200Ω or more

[0108] [Example 1] After applying silicone (trade name: STP-106T-UV, manufactured by Shin-Etsu Chemical Co., Ltd.), it was cured by UV (ultraviolet) to produce a silicone rubber layer with a thickness of 1 μm. Then, a silicone rubber layer with a thickness of 1 μm was bonded to the surface of the anisotropic conductive adhesive layer with a thickness of 6 μm to obtain a connection film.

[0109] Also, for the silicone rubber, in accordance with JIS K 6253, the rubber hardness (JIS-A hardness of Japanese Industrial Standard) was measured using a durometer A. As a result, the rubber hardness was 30. Also, for the silicone rubber, a dynamic viscoelasticity test was conducted using an indentation test apparatus (iMicro type nanoindenter manufactured by KLA). Using a flat punch with a diameter of 100 μm, the target indentation depth was set to 1 μm, the frequency range of 1 to 200 Hz was swept, and the storage modulus at a temperature of 30 °C and a frequency of 200 Hz was measured. Assuming a Poisson's ratio of 0.5 for the sample, the average value of 12 measurement points for each sample was calculated. As a result, the storage modulus was 27 MPa.

[0110] As shown in Table 3, the chip landing rate when the chip component was landed on the silicone rubber layer of the connection film was 98%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded through the connection film was "B".

[0111] [Example 2] A connection film was produced in the same manner as in Example 1, except that a silicone rubber layer with a thickness of 0.5 μm was produced.

[0112] As shown in Table 3, the chip landing rate when the chip component was landed on the silicone rubber layer of the connection film was 90%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded through the connection film was "A".

[0113] [Example 3] A connection film was produced in the same manner as in Example 1, except that a silicone rubber layer with a thickness of 2.0 μm was produced.

[0114] As shown in Table 3, the chip landing rate when the chip component was landed on the silicone rubber layer of the connection film was 100%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded through the connection film was "C".

[0115] [Example 4] After applying 1 μm thick silicone (trade name: STP-106T-UV, manufactured by Shin-Etsu Chemical Co., Ltd.), a large number of holes with a diameter of 1 μm were processed with a convex emboss and UV (ultraviolet) cured to produce a silicone rubber layer. Then, two silicone rubber layers were adjusted and bonded (mesh type) to the surface of the anisotropic conductive adhesive layer with a thickness of 6 μm so that the total thickness was 2 μm to obtain a connection film.

[0116] As shown in Table 3, the chip landing rate when the chip component was landed on the silicone rubber layer of the connection film was 100%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded through the connection film was "A".

[0117] [Example 5] After applying silicone (trade name: STP-106T-UV, manufactured by Shin-Etsu Chemical Co., Ltd.) to a predetermined thickness, a large number of holes with a diameter of 1 μm were processed with a convex emboss and UV (ultraviolet) cured to produce a silicone rubber layer with a protrusion height of 1 μm or more and a total thickness of 2 μm. Then, the silicone rubber layer was bonded (protrusion type) to the surface of the anisotropic conductive adhesive layer with a thickness of 6 μm to obtain a connection film.

[0118] As shown in Table 3, the chip landing rate when the chip component was landed on the silicone rubber layer of the connection film was 100%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded through the connection film was "A".

[0119] [Comparative Example 1] A silicone rubber layer was not laminated on the surface of the anisotropic conductive adhesive layer, and only an anisotropic conductive adhesive layer with a thickness of 6 μm was used as the connection film.

[0120] As shown in Table 3, the chip landing rate when the chip component was landed on the anisotropic conductive adhesive layer was 20%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded via the connection film was "A".

[0121] [Comparative Example 2] To 80 parts by mass of silicone (trade name: STP-106T-UV, manufactured by Shin-Etsu Chemical Co., Ltd.), 20 parts by mass of conductive particles (average particle size 3 μm, resin core metal-coated fine particles, Ni plating thickness 0.2 μm, manufactured by Sekisui Chemical Co., Ltd.) were blended, applied onto a glass substrate with a thickness of 0.5 mm and UV-cured to produce a conductive particle-containing silicone rubber layer with a thickness of 6 μm, and this was used as the connection film.

[0122] As shown in Table 3, the chip landing rate when the chip component was landed on the conductive particle-containing silicone rubber layer was 100%. Also, the evaluation of the conduction resistance of the connection structure in which the chip component and the wiring board were thermocompression bonded via the connection film was "D".

[0123]

Table 3

[0124] As shown in Table 3, in Comparative Example 1, since the silicone rubber layer was not provided on the anisotropic conductive adhesive layer, the chip landing rate was low. In Comparative Example 2, since the connection film was a conductive particle-containing silicone rubber layer, the evaluation of the conduction resistance was poor.

[0125] On the other hand, in Examples 1 to 5, since the silicone rubber layer was provided on the anisotropic conductive adhesive layer, a high chip landing rate could be obtained. Further, in Examples 4 and 5, since the silicone rubber layer had voids inside, such as a mesh type or a protrusion type, the chip component could easily break through the silicone rubber layer, and a good evaluation of conduction resistance could be obtained.

Explanation of Signs

[0126] 10 Chip component substrate, 11 Base material, 12 Release material, 20 Light-emitting element, 21 Body, 22 First conductivity type electrode, 23 Second conductivity type electrode, 30 Wiring substrate, 31 Base material, 32 First electrode, 33 Second electrode, 40 Connection film, 41 Rubber layer, 42 Anisotropic conductive adhesive layer, 50 Connection film, 51 Rubber layer, 52 Anisotropic conductive adhesive layer, 60 Connection film, 61 Rubber layer, 62 Anisotropic conductive adhesive layer, 70 Connection film, 71 Rubber layer, 72 Anisotropic conductive adhesive layer, 80 Connection film, 81 Rubber layer, 82 Anisotropic conductive adhesive layer, 83 Conductive particles, 90 Connection film, 91 Rubber layer, 92 Anisotropic conductive adhesive layer, 93 Conductive particles, 101 LED, 102 Transfer material, 103 Stamp material, 104 Panel substrate, 105 Connection film, 111 LED, 112 Transfer material, 113 Release material, 114 Panel substrate, 115 Connection film

Claims

1. a landing step of placing a chip component provided on a substrate having transparency to laser light opposite a wiring board and landing the chip component on the wiring board side by irradiating the substrate with laser light; a connecting step of connecting the chip component and the wiring board via a connecting film, the connecting film has a rubber layer and an adhesive layer, A method for manufacturing a connection structure, wherein the rubber layer is broken through in the connecting step.

2. The method for producing a connection structure according to claim 1 , wherein the rubber layer is made of at least one rubber selected from the group consisting of acrylic rubber and silicone rubber.

3. The method for manufacturing a connection structure according to claim 1 or 2, wherein the rubber layer has a thickness of 0.5 μm or more and 3.0 μm or less.

4. The method for producing a connection structure according to claim 1 , wherein the rubber layer has voids therein.

5. The method for manufacturing a connection structure described in any one of claims 1 to 4, wherein the durometer A hardness of the rubber layer is 20 to 40, and the storage modulus at a temperature of 30°C and a frequency of 200 Hz in a dynamic viscoelasticity test using an indentation tester is 60 MPa or less.

6. The method for producing a connection structure according to claim 1 , wherein the adhesive layer contains a film-forming resin, a thermosetting resin, and a curing agent.

7. The method for producing a connection structure according to claim 1 , wherein the adhesive layer contains conductive particles.

8. The method for manufacturing a connection structure according to claim 7 , wherein the adhesive layer is configured such that the conductive particles are aligned in a planar direction.

9. The method for manufacturing a connection structure according to claim 1 , wherein the chip component is a light emitting element.

10. The method for manufacturing a connection structure according to claim 1 , wherein the rubber layer is broken through by an electrode of the chip component.

11. The adhesive layer contains conductive particles, The method for manufacturing a connection structure according to claim 1 , wherein the rubber layer is broken through by the conductive particles.

12. a chip component, a wiring board, and a connection film provided between an electrode surface of the chip component and an electrode surface of the wiring board; The connection film is a cured film of a connection film having a rubber layer and an adhesive layer, and the rubber layer is broken through by an electrode of the chip component.

13. a chip component, a wiring board, and a connection film provided between an electrode surface of the chip component and an electrode surface of the wiring board; A connection structure in which the connection film is a cured film of a connection film having a rubber layer and an adhesive layer, the adhesive layer contains conductive particles, and the rubber layer is broken through by the conductive particles.

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