TW202246049A - Connection film and method for manufacturing connection structure - Google Patents

Abstract

Provided are a connection film that makes it possible to obtain excellent elasticity of a chip component by applying a laser beam, and a method for manufacturing a connection structure. The connection film contains a rubber component, has a durometer A hardness of 20-40, and has a storage elastic modulus of 0.2-60 MPa at a temperature of 30 DEG C and a frequency of 200 Hz in a dynamic viscoelasticity test using an indentation test device. Further, the connection film further contains a film-forming resin, a thermosetting resin, a curing agent, and an inorganic filler, and has a storage elastic modulus of 0.1 GPa or more at a temperature of 30 DEG C, which is measured in a tensile mode according to JIS K7244 after curing. This makes it possible to obtain excellent elasticity of a chip component by applying a laser beam.

Description

Connection film and method for manufacturing connection structure

The technology relates to a method of manufacturing a connection film and a connection structure for connecting a chip component to a substrate. This application is based on Japanese Patent Application No. 2021-054274 filed in Japan on March 26, 2021, and Japanese Patent Application No. 2022-047405 filed in Japan on March 23, 2022 Where priority is claimed, these applications are incorporated by reference in this application.

In recent years, the industry has actively developed micro-LEDs as the next-generation displays of LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode). As a subject of micro-LEDs, a technology called mass transfer (Mass Transfer), which requires micro-sized LEDs to be mounted on a panel substrate, is being researched in various places.

As the current main method of mass transfer, there is a method of transferring LEDs to the panel substrate side using a stamp material. Fig. 15 is a diagram schematically showing mass transfer in the form of an impression. In the stamping method, as shown in Figure 15A and Figure 15B, the LED101 is transferred from the transfer material 102 to the stamping material 103 and picked up, as shown in Figure 15C and Figure 15D, and attached to the connection film 105 of the panel substrate 104 LED101. However, the method of using the stamp material is not suitable for mass production because the distance between the LEDs 101 depends on the pattern of the stamp material 103 , the degree of freedom of design is low, the transfer rate of the chip is also low, and it is very time-consuming.

Therefore, attention is currently being paid to a wafer placement method using a laser (see, for example, Patent Documents 1 to 4). Fig. 16 is a diagram schematically showing mass transfer by laser method. In the laser method, as shown in FIG. 16A and FIG. 16B, the LED111 is transferred from the transfer material 112 to the release material 113 and picked up. As shown in FIG. 15C, the laser light is irradiated to the release material 113 to make the LED111 bounce on the connection film 115 of the panel substrate 114 . Compared with impression materials, laser wafer transfer printing has a higher degree of design freedom, and the tact time of wafer transfer is very fast.

However, in the chip placement method using laser, since the LED bounces off and bounces to the panel substrate side at a very fast speed, for example, as shown in FIG. , rupture, etc., or produce defects. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2020-096144 [Patent Document 2] Japanese Patent Laid-Open No. 2020-145243 [Patent Document 3] Japanese Patent Laid-Open No. 2019-176154 [Patent Document 4] Japanese Patent Laid-Open No. 2020-053558

[Problem to be Solved by the Invention]

This technology is proposed in view of such previous actual conditions, and provides a method for manufacturing a connection film and a connection structure capable of obtaining excellent elasticity of chip parts by irradiation of laser light. [Technical means to solve the problem]

The connection film of this technology contains rubber components, the hardness of the A-type durometer is 20-40, and the storage elastic modulus at the temperature of 30°C and the frequency of 200 Hz in the dynamic viscoelasticity test using the indentation test device is 60 MPa or less.

The connecting film substrate of the present technology has the above connecting film and a base material that is transparent to laser light.

The manufacturing method of the bonded structure of the present technology has: the step of snapping, which makes the chip part provided on the base material with permeability to laser light and the connection film on the wiring board face each other, and irradiates laser light from the side of the above-mentioned base material And the above-mentioned chip part is bounced on the above-mentioned connection film; and the connecting step is to connect the above-mentioned chip part to the above-mentioned wiring board; and the above-mentioned connection film contains rubber components, the hardness of the A-type durometer is 20-40, and the temperature is 30 ° C. The storage elastic modulus at a frequency of 200 Hz is 60 MPa or less.

The manufacturing method of the bonded structure of the present technology has: the step of snapping, which makes the connection film provided on the electrode surface of the chip part of the base material having permeability to laser light face the wiring board, and from the above-mentioned base material side irradiating laser light so that the above-mentioned chip part is bounced on the above-mentioned wiring board through the above-mentioned connection film; and a connecting step, which connects the above-mentioned chip part to the above-mentioned wiring board; 20-40, and the storage elastic modulus is below 60 MPa at a temperature of 30°C and a frequency of 200 Hz. [Effect of Invention]

According to this technology, excellent impact absorption can be obtained, so excellent elasticity of chip parts can be obtained.

Hereinafter, embodiments of the present technology will be described in detail in the following order with reference to the drawings. 1. Connecting Membrane 2. Manufacturing method of connecting structure 3. The first embodiment 4. The second embodiment

＜1. Connecting membrane＞ The connection film of this embodiment contains rubber components, the A-type durometer hardness is 20 to 40, and the storage elastic modulus at a temperature of 30°C and a frequency of 200 Hz in a dynamic viscoelasticity test using an indentation test device is 60 MPa or less. In this way, excellent impact absorption can be obtained, so the occurrence of defects such as deviation, deformation, cracking, and falling off of chip parts can be suppressed, and the transfer rate of chip parts irradiated by laser light can be improved.

The rubber component is not particularly limited as long as it is an elastic body with high cushioning properties (impact absorption). Specific examples include acrylic rubber, silicone rubber, butadiene rubber, polyurethane resin (polyurethane) Elastomers), etc. Among them, the rubber component is preferably one or more selected from acrylic rubber and silicone rubber. The content of the rubber component may also be 1-100 wt%, and when a thermosetting resin, thermoplastic resin, etc. are contained, the content of the rubber component is preferably 1-20 wt%, more preferably 2-10 wt%.

The A-type durometer hardness of the connecting film is 20-40, preferably 20-35, more preferably 20-30. When the hardness of the A-type hardness meter is too high, the connecting film is too hard, and there is a tendency to cause defects such as deformation and cracking of the chip parts. Defective tendencies such as deviation of chip parts. The A-type durometer hardness of the connecting film can be measured according to JIS K 6253, using the A-type durometer according to the rubber hardness (Japanese Industrial Standard JIS-A hardness).

The storage elastic modulus of the connecting film in the dynamic viscoelasticity test using an indentation test device at a temperature of 30°C and a frequency of 200 Hz is 60 MPa or less, preferably 30 MPa or less, more preferably 10 MPa or less. When the storage elastic modulus is too high at a temperature of 30°C and a frequency of 200 Hz, the impact of the chip parts ejected at high speed due to laser irradiation cannot be absorbed, and the transfer rate of the chip parts tends to decrease. The storage modulus of elasticity at a temperature of 30°C and a frequency of 200 Hz can be measured using an indentation test device, for example, a flat punch with a diameter of 100 μm is used, and the target indentation depth is set to 1 μm, at a frequency of 1 to 200 Hz Scan and measure within the range.

In addition, the connecting film further contains a film-forming resin, a thermosetting resin, a curing agent, and an inorganic filler. After curing, the storage elastic modulus at a temperature of 30° C. measured in a tensile mode according to JIS K7244 is preferably 100 MPa or more, and furthermore Preferably it is above 2000 MPa. When the storage elastic modulus at a temperature of 30°C is too low, good conductivity cannot be obtained and connection reliability tends to decrease. The storage elastic modulus at a temperature of 30°C can be measured in accordance with JIS K7244 by using a viscoelasticity testing machine (VIBRON) in the tensile mode, for example, under the measurement conditions of a frequency of 11 Hz and a heating rate of 3°C/min.

The thermosetting adhesive containing a film-forming resin, a thermosetting resin, and a curing agent is not particularly limited, and examples thereof include thermal anionic polymerizable resin compositions containing epoxy compounds and thermal anionic Thermal cationic polymerizable resin composition of oxygen compound and thermal cationic polymerization initiator, thermal radical polymerizable resin composition including (meth)acrylate compound and thermal radical polymerization initiator, etc. In addition, a (meth)acrylate compound is meant to include two types of acrylic monomer (oligomer) and methacrylic monomer (oligomer).

Among the thermosetting adhesives, it is preferable that the thermosetting resin contains an epoxy compound, and the curing agent is a thermal cationic polymerization initiator. Thereby, the hardening reaction by laser light can be suppressed, and it can harden rapidly by heat. Hereinafter, as a specific example, a thermal cationic polymerizable resin composition containing a film-forming resin, an epoxy compound, and a thermal cationic polymerizable initiator will be described as an example.

The film-forming resin is, for example, a high-molecular-weight resin corresponding to an average molecular weight of 10,000 or more, and preferably has an average molecular weight of about 10,000 to 80,000 from the viewpoint of film-forming properties. Examples of the film-forming resin include various resins such as phenoxy resins, polyester resins, polyurethane resins, polyester urethane resins, acrylic resins, polyimide resins, and butyral resins, which may be used alone or in combination. Use 2 or more. Among them, it is preferable to use a phenoxy resin from the viewpoints of the state of film formation, connection reliability, and the like. The content of the film-forming resin is preferably 20-50 parts by mass, more preferably 25-45 parts by mass, based on 100 parts by mass of the total of the film-forming resin, thermosetting resin, curing agent, inorganic filler, and rubber component, and further Preferably it is 35-45 mass parts.

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 bisphenol A type epoxy resin, bisphenol F type epoxy resin, etc., or it may be an amine Epoxy resin modified by urethane. Among them, a high-purity bisphenol A type epoxy resin can be preferably used. As a specific example of high-purity bisphenol A type epoxy resin, the brand name "YL980" by Mitsubishi Chemical company is mentioned, for example. The content of the epoxy compound is preferably 30 to 60 parts by mass, more preferably 35 to 55 parts by mass, and still more preferably Preferably, it is 35-45 mass parts.

As the thermal cationic polymerization initiator, those known as thermal cationic polymerization initiators of epoxy compounds can be used, for example, those that generate an acid capable of cationic polymerizing cationic polymerizable compounds by heat, known iodonium salts can be used , Cu salts, phosphonium salts, ferrocenes, etc. Among them, aromatic cobaltium salts showing good potential to temperature are preferably used. As a specific example of the polymerization initiator of the aromatic cobaltium salt type, the product name "SI-60L" by Sanshin Chemical Industry Co., Ltd. is mentioned, for example. The content of the thermal cationic polymerization initiator is preferably 1 to 15 parts by mass, more preferably 1 to 10 parts by mass, based on 100 parts by mass of the total of the film-forming resin, thermosetting resin, hardener, inorganic filler, and rubber component. parts, more preferably 3 to 8 parts by mass.

The inorganic filler can be used for the purpose of adjusting the A-type durometer hardness of the thermosetting adhesive, the storage elastic modulus at a frequency of 200 Hz, and the storage elastic modulus after hardening. As the inorganic filler, silica, talc, titanium oxide, calcium carbonate, magnesium oxide, and the like can be used. The inorganic fillers may be used alone or in combination of two or more.

The content of the inorganic filler is preferably 1 to 20 parts by mass, more preferably 5 to 15 parts by mass, and still more preferably 100 parts by mass of the total of the film forming resin, thermosetting resin, hardener, inorganic filler, and rubber component Preferably, it is 8-12 mass parts. When two or more types of inorganic fillers are used in combination, the total content of the inorganic fillers in the thermosetting adhesive is preferably within the above range. In particular, the content of the rubber component is 2 to 10 parts by mass relative to the total of 100 parts by mass of the film-forming resin, thermosetting resin, curing agent, inorganic filler, and rubber component, and the content of the inorganic filler is relative to the film-forming resin, The total of 100 parts by mass of thermosetting resin, curing agent, inorganic filler, and rubber component is 8 to 12 parts by mass, so that the desired A-type durometer hardness and storage modulus of elasticity at a frequency of 200 Hz can be obtained , and the storage elastic modulus after hardening.

Furthermore, as other additives blended into the thermosetting adhesive, silane coupling agents, diluting monomers, fillers, softeners, colorants, flame retardants, thixotropic agents, etc. may be blended as needed.

等樹脂粒子之表面而得之金屬被覆樹脂粒子等。藉此，即便於晶片零件未設有焊料凸塊等連接部位之情形時，亦能夠傳導。Moreover, a connection film may contain electroconductive particle further, and may be an anisotropic electroconductive film. As the conductive particles, "used in known anisotropic conductive films" can be appropriately selected and used. For example, metal particles such as nickel, copper, silver, gold, palladium, and solder;

Metal-coated resin particles obtained on the surface of resin particles, etc. This enables conduction even when the chip component is not provided with connection parts such as solder bumps.

Moreover, it is preferable that conductive particles are arranged in the plane direction and constituted. By arranging the conductive particles in the plane direction, the surface density of the particles becomes uniform, and the transfer rate of the chip parts by the irradiation of laser light can be improved.

The particle size of the conductive particles is not particularly limited, the lower limit of the particle size is preferably 2 μm or more, and the upper limit of the particle size is preferably, for example, 50 μm or less from the viewpoint of the capture efficiency of the conductive particles in the bonded structure, Furthermore, it is preferably 20 μm or less. In addition, the particle diameter of an electrically-conductive particle can be made into the value measured with the image type particle size distribution meter (One example is FPIA-3000: Malvern company make). Preferably, the number is 1000 or more, more preferably 2000 or more. Also, the surface density of conductive particles can be determined according to the electrode area of the chip component, etc., and can be set in the range of 500 to 100,000 pcs/mm ² , for example.

The lower limit of the thickness of the connection film may be the same as the particle size of the conductive particles, for example, preferably at least 1.3 times the size of the conductive particles or at least 3 μm. In addition, the upper limit of the thickness of the connecting film can be, for example, 20 μm or less or twice the particle size of the conductive particles or less. In addition, the connection film may be formed by laminating an adhesive layer or an adhesive layer that does not contain conductive particles, and the number of layers or lamination layers can be appropriately selected according to the object or purpose. Moreover, as an insulating resin of an adhesive layer or an adhesive layer, the thing similar to that of a connection film can be used. The film thickness can be measured using a known micrometer or digital thickness gauge. The film thickness may be obtained by measuring, for example, at 10 or more points and averaging them. ＜2. Manufacturing method of bonded structure＞

[First Embodiment] The method of manufacturing the bonded structure according to the first embodiment includes: a snapping step, which makes the chip component provided on the base material transparent to laser light and the connection film on the wiring board face each other, and from the side of the base material Irradiate the laser light to make the chip parts bounce on the connecting film; and the connecting step, which connects the chip parts and the wiring board; and the connecting film contains rubber components, the hardness of the A-type durometer is 20-40, the temperature is 30 ° C, and the frequency is 200 The storage elastic modulus at Hz is below 60 MPa. In this way, in the landing step, defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency, so the tact time can be shortened.

The chip parts are not particularly limited, and examples thereof include semiconductor chips, LED chips, and the like. The method of manufacturing a bonded structure according to this technology can be suitably used to mount a large number of micro-sized LED chips on a large amount of a panel substrate as a wiring board. transfer.

Hereinafter, as a method of manufacturing a bonded structure, a method of manufacturing a display device in which a plurality of light emitting elements serving as LED chips are arranged on a wiring board serving as a panel substrate to form a light emitting element array will be described.

As a 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, forming an array of light-emitting elements. For example, 1 pixel may be composed of three sub-pixels R (red), G (green) and B (blue), four sub-pixels RGBW (white) and RGBY (yellow), or two sub-pixels RG and GB.

As an arrangement method of sub-pixels, for example, in the case of RGB, stripe arrangement, mosaic arrangement, triangle arrangement, etc. can be mentioned. The stripe arrangement is formed by arranging RGB in vertical stripes, which can achieve high definition. In addition, the mosaic arrangement is formed by diagonally arranging the same color of RGB, which can obtain a more natural image than the strip arrangement. In addition, the triangular arrangement is formed by arranging RGB in a triangular form and shifting each point by half a pitch for each field, so that a natural image display can be obtained.

Table 1 shows the estimated lateral pitch between RGB, estimated chip size, and estimated electrode size for PPI (Pixels Per Inch) when RGB chips are arranged laterally. Assuming that the minimum distance between chips is 5 μm, the distance between RGB is estimated to be the largest when they are arranged at equal intervals. This equivalent value is calculated as a reference value for researching this technology when the usage becomes clear.

[Table 1] size ppi Pixel pitch (μm) Estimated horizontal pitch between RGB (μm) Estimated Die Size Estimated electrode size use Inches Horizontal (mm) Longitudinal (mm) Horizontal (μm) Longitudinal (μm) Minimum (μm) Maximum (μm) Minimum (μm) Maximum (μm) Minimum (μm) Maximum (μm) large monitor 120 2657 1494 40 635 635 15 212 10×20 207×417 7×7 150×150 2657 1494 100 254 254 15 85 10×20 80×160 7×7 60×60 Large TV 80 1771 996 80 318 318 15 106 10×20 101×202 7×7 70×70 1771 996 120 212 212 15 71 10×20 66×132 7×7 45×45 medium monitor 20 443 249 100 254 254 15 85 10×20 80×160 7×7 55×55 443 249 200 127 127 15 42 10×20 37×74 7×7 25×25 flat 10 221 125 200 127 127 15 42 10×20 37×74 7×7 25×25 221 125 400 64 64 15 twenty one 10×20 16×32 7×7 10×10 SMP 6 13.26 7.47 300 85 85 15 28 10×20 23×46 7×7 15×15 13.26 7.47 500 51 51 15 17 10×20 12×24 7×7 8×8 Watch 2 3.59 3.59 300 85 85 15 28 10×20 23×46 7×7 15×15 3.59 3.59 500 51 51 15 17 10×20 12×24 7×7 8×8 VR 1 1.80 1.80 500 51 51 15 17 10×20 12×24 7×7 8×8 1.80 1.80 1000 26 26 9 9 7×14 7×14 5×5 5×5 1.80 1.80 2000 13 13 4 4 - - - -

As shown in Table 1, it can be seen that by making the wafer size 10×20 μm, it can correspond to a maximum of 500 PPI. Also, by making the chip size 7×14 μm, it can correspond to 1000 PPI at most, and by further reducing the chip size, it is possible to realize 1000 PPI or more. Furthermore, the chip does not necessarily have to be a rectangle, but can also be a square.

Hereinafter, referring to FIGS. 1 to 4 , the landing step (A1) of irradiating the light-emitting element onto the anisotropic conductive film and the connection step (B1) of connecting the light-emitting element to the wiring board will be described. .

[Impact step (A1)] Fig. 1 is a cross-sectional view schematically showing a state in which a light-emitting element provided on a substrate faces an anisotropic conductive film on a wiring board, and Fig. 2 shows a connection between the facing light-emitting element and a connection film on a wiring board. Zoom in on the graph. As shown in FIGS. 1 and 2 , first, in the landing step ( A1 ), the chip component substrate 10 and the anisotropic conductive film 40 on the wiring substrate 30 are made to face each other.

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 on the surface of the release material 12 . The base material 11 is only required to be transparent to laser light, among which quartz glass with high light transmittance at all wavelengths is preferred.

The release material 12 only needs to have absorption characteristics for the wavelength of the laser light, and the irradiation of the laser light generates a shock wave, which bounces the light emitting element 20 toward the wiring board 30 side. As the release material 12, polyimide is mentioned, for example. The thickness T12 of the release material 12 is, for example, 1 μm or more.

The light emitting element 20 includes a body 21 , a first conductivity type electrode 22 , and a second conductivity type electrode 23 , and the first conductivity type electrode 22 and the second conductivity type electrode 23 have a horizontal structure arranged on the same side. The main body 21 has a first conductivity type cladding layer made of _{n-GaN, an active layer made of InxAlyGa1-x - yN layer , and a} second conductivity type cladding layer made of p-GaN, for example. The cladding layer has a so-called double heterostructure. The first conductivity type electrode 22 is formed on a part of the first conductivity type coating layer through a passivation layer, and the second conductivity type electrode 23 is formed on a part of the second conductivity type coating layer. When a voltage is applied between the first conductivity type electrode 22 and the second conductivity type electrode 23, carriers gather in the active layer and recombine, whereby light is emitted.

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

The wiring board 30 is provided with a circuit pattern for the first conductivity type and a circuit pattern for the second conductivity type on the base material 31, and the light-emitting elements are arranged in units of sub-pixels (sub-pixels) constituting one pixel, for example, on the p-side There are first electrodes 32 and second electrodes 33 at positions corresponding to the electrodes of the first conductivity type and the electrodes of the second conductivity type on the n side, respectively. In addition, circuit patterns such as data lines and address lines of matrix wiring are formed on the wiring board 30 , and light-emitting elements corresponding to each sub-pixel constituting one pixel can be turned on/off. Furthermore, the wiring substrate 30 is preferably a light-transmitting substrate, the substrate 31 is preferably glass, PET (Polyethylene Terephthalate, polyethylene terephthalate), etc., and the circuit pattern, the first electrode 32 and the second electrode 33 are preferably ITO (Indium-Tin-Oxide, indium tin oxide), IZO (Indium-Zinc-Oxide, indium zinc oxide), ZnO (Zinc-Oxide, zinc oxide), IGZO (Indium-Gallium-Zinc-Oxide, indium gallium oxide Zinc) and other transparent conductive films.

The anisotropic conductive film 40 contains conductive particles in the binder, and the thickness T40 of the anisotropic conductive film 40 is, for example, 20 μm or less. Also, the distance D between the light emitting element 20 and the anisotropic conductive film 40 is preferably 10-1000 μm, more preferably 50-500 μm, and still more preferably 80-200 μm.

Fig. 3 is a cross-sectional view schematically showing a state in which a light-emitting element is transferred and arranged at a specific position on a wiring board by irradiating laser light from the substrate side. As shown in FIGS. 2 and 3 , in the landing step ( A1 ), laser light 50 is irradiated from the substrate 11 side to transfer and arrange the light-emitting elements 20 to specific positions on the wiring substrate 30 .

For the transfer of the light-emitting element 20 , for example, a laser induced forward transfer (LIFT: Laser Induced Forward Transfer) device can be used. The laser-induced forward transfer device includes, for example: a telescope, which makes the pulsed laser light emitted from the laser device become parallel light; a shaping optical system, which uniformly shapes the spatial intensity distribution of the pulsed laser light passing through the telescope; a mask, It passes the pulsed laser light shaped by the shaping optical system in a specific pattern; the field lens, which is located between the shaping optical system and the mask; and the projection lens, which reduces the laser light passing through the pattern of the mask and projects it to the donor Substrate; and hold the wafer component substrate 10 as the donor substrate on the donor stage, and hold the wiring substrate 30 as the acceptor substrate on the acceptor stage.

As the laser device, for example, an excimer laser that oscillates laser light having a wavelength of 180 nm to 360 nm can be used. The oscillation wavelength of the excimer laser is, for example, 193, 248, 308, and 351 nm, and can be appropriately selected from among these oscillation wavelengths according to the light absorption of the material of the release material 12 .

The mask is patterned with an array of openings of a specific size formed at a specific pitch, so that the projection at the interface between the substrate 11 and the release material 12 becomes a desired array of laser light. In the mask, a pattern is applied to the base material 11 by, for example, chrome plating, and the opening portion not subjected to chrome plating allows the laser light to pass through, while the portion subjected to chrome plating blocks the laser light.

The outgoing light from the laser device enters the telescope optical system and is transmitted to the shaping optical system at its front end. The laser light that is about to be incident on the shaping optical system is adjusted by the telescope optical system in the form of approximately parallel light at any position within the X-axis movement range of the donor stage, so it is often approximately the same size, The same angle (perpendicular) incidence to the shaping optics.

The laser light that passes through the shaping optical system enters the mask through the field lens that constitutes the telecentric reduction projection optical system on the image side in combination with the projection lens. The transmission direction of the laser light passing through the mask pattern is changed to be vertically downward by the vertical illuminating mirror, so that it enters the projection lens. The laser light emitted from the projection lens enters from the side of the substrate 11 and is accurately projected to a specific position of the release material 12 formed on the surface (lower surface) of the substrate 11 with the reduced size of the mask pattern.

The pulse energy of the imaging laser light irradiated to the interface between the anisotropic conductive adhesive layer and the substrate is preferably 0.001-2 J, more preferably 0.01-1.5 J, and still more preferably 0.1-1 J. The flux (fluence) is preferably 0.001-2 J/cm ² , more preferably 0.01-1 J/cm ² , and still more preferably 0.05-0.5 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 still more preferably 1 to 1×10 ⁵ picoseconds. The pulse frequency is preferably from 0.1 to 10000 Hz, more preferably from 1 to 1000 Hz, further preferably from 1 to 100 Hz. The number of irradiation pulses is preferably from 1 to 30,000,000.

By using such a laser-induced forward transfer device, the release material 12 irradiated with laser light can generate shock waves at the interface between the base material 11 and the release material 12, and a plurality of light-emitting elements 20 can be transferred from the base material 11. The laser-induced forward transfer is performed toward the wiring substrate 30 after peeling off, so that a plurality of light-emitting elements 20 are bounced to specific positions of the wiring substrate 30 through the anisotropic conductive film 40 . Thereby, defects such as deviation, deformation, cracking, and falling off of the light-emitting element 20 can be suppressed, and the light-emitting element 20 can be transferred and arranged with high precision and high efficiency, so that the cycle time can be shortened.

[Connection procedure (B1)] Fig. 4 is a cross-sectional view schematically showing a state in which a light emitting element is mounted on a wiring board. As shown in FIG. 4 , in the connecting step ( B1 ), the light emitting elements 20 arranged at specific positions on the wiring substrate 30 are mounted.

As a method of thermocompression-bonding the light-emitting element 20 to the wiring board 30, a connection method used for a known anisotropic conductive film can be appropriately selected and used. The thermocompression bonding conditions are, for example, a temperature of 120° C. to 260° C., a pressure of 5 MPa to 60 MPa, and a time of 5 seconds to 300 seconds. The anisotropic conductive film is formed by curing the anisotropic conductive film.

According to the method of manufacturing a bonded structure according to the first embodiment, the bonded film contains a rubber component, has a hardness of 20 to 40 on a type A durometer, and has a storage elastic modulus of 60 MPa or less at a temperature of 30°C and a frequency of 200 Hz. In the landing step (A1), defects such as deviation, deformation, cracking, and falling off of chip parts can be suppressed, and chip parts can be transferred and arranged with high precision and high efficiency, so cycle time can be shortened.

[Second Embodiment] In the first embodiment, the connection film is attached on the wiring board, but it is also possible to transfer a single piece of the connection film to a specific position on the wiring board by irradiating laser light. In the step of bouncing (A1), The chip parts are bounced on the single piece of the bonding film.

That is, the method of manufacturing a bonded structure according to the second embodiment includes a transfer step of making the connection film provided on the base material transparent to laser light face the wiring board, and irradiating laser light from the base material side. Transferring a single piece of the connection film to the wiring substrate; the snapping step, which makes the chip parts set on the substrate that is transparent to laser light and the connection film on the wiring substrate face each other, and irradiates from the above substrate side The chip part is bounced on the single piece of the connection film by laser light; and the connection step is to connect the chip part to the wiring substrate; and the connection film contains rubber components, the hardness of the A-type hardness meter is 20-40, and the temperature is 30 ° C , The storage modulus of elasticity at a frequency of 200 Hz is below 60 MPa.

Thereby, a single piece of connecting film can be transferred and arranged with high precision and high efficiency by irradiation of laser light. Also, similar to the first embodiment, in the bumping step, the generation of defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency, so it is possible to Realize shortening of takt time.

Hereinafter, with reference to FIGS. 5 to 9 , the transfer step (X) of transferring and arranging the monolithic anisotropic conductive film to a specific position on the wiring board, irradiating the light-emitting element with laser light to make the light-emitting element bounce on the anisotropic The bouncing step (A2) on the single sheet of the conductive film and the connection step (B2) of connecting the light-emitting element and the wiring board will be described. In addition, the same code|symbol is attached|subjected to the same structure as 1st Embodiment, and description is abbreviate|omitted.

[Transfer step (X)] Fig. 5 is a cross-sectional view schematically showing a state in which the anisotropic conductive film provided on the base and the wiring board face each other. As shown in FIG. 5 , first, in the transfer step (X), the anisotropic conductive film substrate 60 is made to face the wiring substrate 30 .

The anisotropic conductive film substrate 60 includes a substrate 61 and an anisotropic conductive film 70 , and the anisotropic conductive film 70 is provided on the surface of the substrate 61 . The substrate 61 only needs to be transparent to laser light, among which quartz glass with high light transmittance at all wavelengths is preferred. Furthermore, a release material may be further provided between the base material 61 and the anisotropic conductive film 70 .

From the viewpoint of laser transferability, the anisotropic conductive film 70 is preferably constituted by arranging conductive particles in the plane direction. In addition, the anisotropic conductive film 70 preferably has a maximum absorption wavelength at a wavelength of 180 nm to 360 nm, for example, and an epoxy-based adhesive including high-purity bisphenol A epoxy resin or the like can be preferably used.

6 is a cross-sectional view schematically showing a state in which a single sheet of an anisotropic conductive film is transferred and arranged to a specific position on a wiring board by irradiating laser light from the substrate side. As shown in FIG. 6 , in the transfer step (X), laser light is irradiated from the substrate 61 side to transfer and arrange the single piece 70 a of the anisotropic conductive film 70 to a specific position on the wiring board 30 .

In the transfer step (X), it is preferable to arrange the individual pieces 70 a of the anisotropic conductive film 70 in units of 1 pixel, and more preferably to arrange in units of sub-pixels constituting 1 pixel. Thereby, it can correspond to a light-emitting element array with a higher PPI (Pixels Per Inch) to a light-emitting element array with a lower PPI.

Also, the distance between the individual chips arranged at a specific position on the wiring board 30 is preferably 3 μm or more, more preferably 5 μm or more, and still more preferably 10 μm or more. Also, the upper limit of the distance between individual chips is preferably at most 3000 μm, more preferably at most 1000 μm, and still more preferably at most 500 μm. When the distance between the chips is too small, it is preferable to attach an anisotropic conductive film to the entire surface of the wiring substrate 30. When the distance between the chips is too large, it is preferable to apply an anisotropic conductive film A method of attaching a film to a specific position of the wiring board 30 .

The transfer of the single piece 70a of the anisotropic conductive film 70 can use the same laser-induced forward transfer device as above, and the anisotropic conductive film substrate 60 as the donor substrate is held on the donor stage, and the substrate 60 as the acceptor The wiring substrate 30 of the substrate is held on the receptor stage. The distance between the anisotropic conductive film 70 and the wiring board 30 is, for example, 10 to 100 μm. The oscillation wavelengths of the laser device are, for example, 193, 248, 308, and 351 nm, and can be appropriately selected from among these oscillation wavelengths according to the light absorption properties of the anisotropic conductive film 70 or the material of the release material.

By using a laser-induced forward transfer device, shock waves can be generated on the anisotropic conductive film 70 irradiated with laser light at the interface between the substrate 61 and the anisotropic conductive film 70, and a plurality of single pieces 70a The laser-induced forward transfer is performed from the base material 61 toward the wiring substrate 30 , so that a plurality of single pieces 70 a are bounced to a specific position of the wiring substrate 30 . Thereby, the single piece 70a of the anisotropic conductive film 70 can be transferred and arranged to the wiring board 30 with high precision and high efficiency, and shortening of the tact time can be realized.

The reaction rate of the monolithic sheet 70a of the anisotropic conductive film 70 after the transfer step (X) is preferably 25% or less, more preferably 20% or less, further preferably 15% or less. By making the reaction rate of the monolith 70a 25% or less, the light-emitting element can be bonded by thermocompression in the connection step (B2). The measurement of the reaction rate can be calculated|required using FT-IR, for example.

[Flick step (A2)] Fig. 7 is a schematic cross-sectional view showing a state in which a light-emitting element provided on a substrate faces an anisotropic conductive film on a wiring board, and Fig. 8 is a schematic diagram showing a state where laser light is irradiated from the substrate A cross-sectional view of the state of transferring and arranging to a specific position on a wiring board.

As shown in FIG. 7 , first, in the landing step ( A2 ), the single piece 70 a of the anisotropic conductive film on the wafer component substrate 10 and the wiring substrate 30 is opposed to each other. Then, as shown in FIG. 8 , laser light is irradiated from the substrate 11 side, and the light emitting elements 20 are transferred and arranged on the single piece 70 a of the anisotropic conductive film of the wiring board 30 . The transfer of the light-emitting element 20 can be the same as that of the first embodiment, for example, using a laser-induced forward transfer device.

[Connection procedure (B2)] Fig. 9 is a cross-sectional view schematically showing a state in which a light emitting element is mounted on a single chip arranged at a specific position on a wiring board. As shown in FIG. 9 , in the connecting step ( B2 ), the light emitting elements 20 arranged on the single piece 70 a at a specific position of the wiring substrate 30 are mounted. The method of thermocompression bonding the light emitting element 20 to the wiring board 30 is the same as that of the first embodiment.

According to the method of manufacturing a bonded structure according to the second embodiment, the bonded film contains a rubber component, has a hardness of 20 to 40 on a type A durometer, and has a storage elastic modulus of 60 MPa or less at a temperature of 30°C and a frequency of 200 Hz. In the landing step (A2), defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency, so the cycle time can be shortened .

In addition, in the state where there is no anisotropic conductive film between the light-emitting elements 20 and the wiring substrate 30 is exposed, the light-emitting element 20 can be anisotropically connected to the wiring substrate 30. Therefore, by making the wiring substrate 30 a light-transmitting substrate , compared with the case where the anisotropic conductive film is attached to the entire surface of the wiring board 30, excellent light transmittance can be obtained.

[Modification of the second embodiment] In the transfer step (X) of the second embodiment, laser light may be irradiated from the substrate 61 side to transfer and arrange a single piece of the anisotropic conductive film 70 in units of electrodes of light-emitting elements. That is, the method of manufacturing a bonded structure according to the modified example of the second embodiment further includes a transfer step of making the connection film provided on the base material transparent to laser light and the wiring board face each other. The side of the material is irradiated with laser light, and the single piece of the connection film is transferred to the wiring substrate in units of electrodes. In the step of popping, the chip parts are bounced on the single piece of the corresponding electrode.

Thereby, in the light-emitting element 20 having the horizontal structure in which the first conductivity type electrode 22 and the second conductivity type electrode 23 are arranged on the same side, the interference between the first conductivity type electrode 22 and the second conductivity type electrode 23 can be suppressed. A short circuit occurs.

Hereinafter, with reference to FIGS. 10 to 13, the transfer step (X-1) of transferring and arranging the single piece of the anisotropic conductive film to a specific position on the wiring board, and irradiating the light emitting element with laser light to make the light emitting element bounce on each The step of bouncing the anisotropic conductive film on a single sheet (A2-1) and the connection step (B2-1) of connecting the light-emitting element to the wiring board will be described. In addition, the same code|symbol is attached|subjected to the same structure as 2nd Embodiment, and description is abbreviate|omitted.

[Transfer Step (X-1)] First, in the transfer step (X-1), as in the transfer step (X) of the second embodiment, as shown in FIG. 5 , the anisotropic conductive film substrate 60 is opposed to the wiring board 30 .

10 is a cross-sectional view schematically showing a state in which a single piece of anisotropic conductive film is transferred and arranged on a wiring board in units of electrodes by irradiating laser light from the substrate side. As shown in FIG. 10 , in the transfer step (X-1), laser light is irradiated from the substrate 61 side, and the individual pieces 72 and 73 of the anisotropic conductive film 70 are transferred and arranged on the wiring in units of electrodes. on the substrate 30.

In the transfer step (X-1), the single pieces 72 and 73 of the anisotropic conductive film 70 are respectively transferred and arranged to the positions corresponding to the first conductive type electrode 22 and the second conductive type electrode 23 of the light emitting element 20 The first electrode 32 and the second electrode 33 . By transferring and arranging the single pieces 72 and 73 to only the first electrode 32 and the second electrode 33 , it is possible to suppress the occurrence of a short circuit between the first conductivity type electrode 22 and the second conductivity type electrode 23 .

The transfer of the monoliths 72 and 73 of the anisotropic conductive film 70 can use the same laser-induced forward transfer device as above, and the monoliths 72 and 73 of the anisotropic conductive film 70 can be printed with electrodes with high precision and high efficiency. By transferring and arranging in units on the wiring board 30, the tact time can be shortened.

The reaction rate of the single pieces 72 and 73 of the anisotropic conductive film 70 after the transfer step (X-1) is the same as that of the second embodiment and the transfer step (X), preferably 25% or less, more preferably 20% % or less, more preferably 15% or less. By making the reaction rate of the monolith 70a 25% or less, the light-emitting element can be bonded by thermocompression in the connection step (B2-1). The measurement of the reaction rate can be calculated|required using FT-IR, for example.

[Impact step (A2-1)] Fig. 11 is a cross-sectional view schematically showing a state in which a light-emitting element provided on a substrate faces a monolithic sheet transferred and arranged on a wiring board in units of electrodes, and Fig. 12 is a schematic view from the substrate side A cross-sectional view of a monolithic state in which light-emitting elements are bounced and arranged on corresponding electrodes by irradiating laser light.

As shown in FIG. 11 , first, in the landing step (A2-1), the chip component substrate 10 and the wiring substrate 30 are opposed to each other, and the individual pieces 72 respectively transferred to the first electrode 32 and the second electrode 33 are , 73 , and align with the first conductivity type electrode 22 and the second conductivity type electrode 23 of the light emitting element 20 disposed on the chip component substrate 10 . Then, as shown in FIG. 12 , laser light is irradiated from the substrate 11 side, and the light-emitting element 20 is bounced onto the monoliths 72 and 73 on the corresponding electrodes. Similar to the first embodiment, for example, a laser-induced forward transfer device can be used for the transfer of the light-emitting element 20 .

[Connection procedure (B2-1)] Fig. 13 is a cross-sectional view schematically showing a state in which a light emitting element is mounted on a single piece of a wiring board. As shown in FIG. 13 , in the connection step ( B2 - 1 ), the light emitting element 20 transferred to the wiring board 30 is mounted. The method of thermocompression bonding the light emitting element 20 to the wiring board 30 is the same as that of the first embodiment.

According to the manufacturing method of the connection structure of the modification of the second embodiment, the connection film contains rubber components, the hardness of the A-type durometer is 20-40, and the storage elastic modulus is 60 MPa or less at a temperature of 30°C and a frequency of 200 Hz. Therefore, in the landing step (A22-1), the occurrence of defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency, so it is possible to achieve takt shortening of time.

In addition, in the state where the anisotropic conductive film is not present between the first conductivity type electrode 22 and the second conductivity type electrode 23 of the light emitting element 20, and the wiring substrate 30 is exposed, the light emitting element 20 can be anisotropically connected to the On the wiring substrate 30, compared with the case where a single piece of anisotropic conductive film is attached across the gap between the first conductivity type electrode 22 and the second conductivity type electrode 23, the generation of a short circuit can be suppressed.

[third embodiment] In the second embodiment, a single piece of the connection film is transferred to a specific position on the wiring board by irradiating laser light, but the connection film may be provided in advance on the electrodes of the chip components.

That is, the method of manufacturing the bonded structure according to the third embodiment includes: a bouncing step of making the connection film provided on the electrode surface of the chip component of the base material transparent to laser light face the wiring board, and from the base The side of the material is irradiated with laser light to make the chip parts bounce on the wiring substrate through the connecting film; and the connecting step is to connect the chip parts to the above wiring substrate; and the connecting film contains rubber components, and the hardness of the A-type durometer is 20~ 40. The storage elastic modulus is below 60 MPa at a temperature of 30°C and a frequency of 200 Hz.

Thereby, similar to the first embodiment, in the bounce step, the occurrence of defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency. Therefore, The shortening of takt time can be realized.

Hereinafter, referring to FIG. 14 , the landing step (A3) of irradiating the light-emitting element on the single sheet of the anisotropic conductive film by irradiating laser light and the connecting step (B3) of connecting the light-emitting element to the wiring board will be described. . In addition, the same code|symbol is attached|subjected to the same structure as 1st Embodiment and 2nd Embodiment, and description is abbreviate|omitted.

[Flick step (A3)] 14 is a cross-sectional view schematically showing a state in which a connection film provided on an electrode surface of a light-emitting element faces a wiring board. As shown in FIG. 14 , first, in the landing step ( A3 ), the wafer component substrate 10 and the wiring substrate 30 are made to face each other. An anisotropic conductive film 80 is provided on the electrode surface of the light emitting element 20 , and the distance between the anisotropic conductive film 80 and the wiring substrate 30 is, for example, 10-100 μm.

The method of disposing the anisotropic conductive film 80 on the electrode surface of the light-emitting element 20 is not particularly limited. For example, as in the transfer step (X) of the second embodiment, the anisotropic conductive film 80 can also be disposed on an electrode surface that is transparent to laser light. The anisotropic conductive film of the substrate faces the electrode surface of the light-emitting element, and laser light is irradiated from the substrate side to transfer a single piece of the anisotropic conductive film to the electrode surface of the light-emitting element.

Next, laser light is irradiated from the base material 11 side, and the light emitting element 20 is transferred and arranged on the wiring board 30 via the anisotropic conductive film 80 . The transfer of the light-emitting element 20 is the same as that of the first embodiment, for example, a laser-induced forward transfer device can be used.

[Connection procedure (B3)] In the connecting step ( B3 ), the light emitting elements 20 arranged at specific 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 of the first embodiment.

According to the method of manufacturing a bonded structure according to the third embodiment, the bonded film contains a rubber component, has a hardness of 20 to 40 on a type A durometer, and has a storage elastic modulus of 60 MPa or less at a temperature of 30°C and a frequency of 200 Hz. In the landing step (A3), defects such as deviation, deformation, cracking, and falling off of the chip parts can be suppressed, and the chip parts can be transferred and arranged with high precision and high efficiency, so the cycle time can be shortened .

In addition, in a state where there is no anisotropic conductive film between the light emitting elements 20 and the wiring substrate 30 is exposed, the light emitting element 20 can be anisotropically connected to the wiring substrate 30. Therefore, by making the wiring substrate 30 light-transmitting The substrate can obtain superior light transmittance compared to the case where the anisotropic conductive film is attached to the entire surface of the wiring substrate 30 . [Example]

<3. The first embodiment> In the first embodiment, the wafer component provided on quartz glass is opposed to the connection film on the glass substrate, and laser light is irradiated from the base material side to cause the chip component to bounce on the connection film. In addition, this embodiment is not limited to these.

[Production of connecting film] Prepare the following materials. Phenoxy resin (trade name: PKHH, manufactured by Pakistan Chemical Industry Co., Ltd.) High-purity bisphenol A type epoxy resin (trade name: YL-980, manufactured by Mitsubishi Chemical Co., Ltd.) Hydrophobic silica (trade name: R202, manufactured by Japan Aerosil Co., Ltd.) Acrylic rubber (trade name: SG80H, manufactured by Nagase chemteX Co., Ltd.) Cationic polymerization initiator (trade name: SI-60L, manufactured by Sanshin Chemical Industry Co., Ltd.) Silicone rubber (trade name: STP-106T-UV, manufactured by Shin-Etsu Silicones Co., Ltd.) Conductive particles (average particle size 2.2 μm, resin core metal-coated fine particles, Ni-plated with a thickness of 0.2 μm, manufactured by Sekisui Chemical Co., Ltd.)

As shown in Table 2, each material was blended in specific mass parts, and a resin layer with a specific thickness was prepared on a glass substrate with a thickness of 0.5 mm. According to the method described in Japanese Patent No. 6187665, from the obtained resin layer, the conductive particles are arranged in such a way that one interface of the resin layer is roughly consistent with the conductive particles, and the surface density of the particles becomes 58000 pcs/mm ² , Fabricate connecting films 1 to 5. The connection film 6 is obtained by coating polysiloxane rubber on the glass substrate and making it uv-hardened. The connecting film 7 is obtained by thermoforming acrylic rubber on a glass substrate.

[Measurement of Rubber Hardness of Connecting Membrane] According to JIS K 6253, rubber hardness was measured using a type A durometer (Japanese Industrial Standard JIS-A hardness).

[Determination of the storage elastic modulus of the connecting film] A dynamic viscoelasticity test was performed using an indentation test device (iMicro nanoindenter manufactured by KLA Corporation). Use a flat punch with a diameter of 100 μm, set the target indentation depth to 1 μm, scan in the frequency range of 1-200 Hz, and measure the storage elastic modulus at a temperature of 30 °C and a frequency of 200 Hz. The Poisson's ratio of the sample was set to 0.5, and the average value of 12 measurement points of each sample was calculated.

[Measurement of the storage modulus of elasticity of the connecting film after hardening] Regarding the connecting film after hardening, the storage elastic modulus at a temperature of 30° C. was measured in a tension mode using a viscoelasticity testing machine (VIBRON) according to JIS K7244. The measurement conditions were set at a frequency of 11 Hz and a heating rate of 3°C/min.

[Table 2] connective membrane 1 connective membrane 2 connective membrane 3 connective membrane 4 connective membrane 5 connective membrane 6 connective membrane 7 Phenoxy resin 36 42 42 37 35 - - epoxy resin 40 40 40 37 45 - - Hydrophobic silica 11 10 10 15 5 - - acrylic rubber 8 3 3 6 14 100 - silicone rubber - - - - - - 100 cationic polymerization initiator 5 5 5 5 5 - - conductive particles 20 20 20 20 20 20 20 Thickness [μm] 4 4 20 4 4 4 4 Rubber hardness twenty three 31 31 45 8 20 30 200 Hz elastic modulus [MPa] 0.2 10 10 30 0.1 52 27 Modulus of elasticity after hardening [MPa] >2000 >2000 >2000 >2000 >2000 52 27

[Transfer printing of chip parts] Using a laser-induced forward transfer device (MT-30C200), the wafer parts set on the quartz glass are bounced to the connection film on the glass substrate. The chip part (outline 30×50 μm, thickness 5 μm) uses TEG (Test Element Group), and a release material (polyimide) is set between the quartz glass and the chip part.

As mentioned above, the laser-induced forward transfer device has: a telescope, which makes the pulsed laser light emitted from the laser device parallel to light; a shaping optical system, which uniformly shapes the spatial intensity distribution of the pulsed laser light passing through the telescope; A mask, which makes the pulsed laser light shaped by the shaping optical system pass through in a specific pattern; a field lens, which is located between the shaping optical system and the mask; and a projection lens, which reduces and projects the laser light passing through the pattern of the mask To the donor substrate; and hold the quartz substrate with the wafer parts held by the release material as the donor substrate on the donor stage, and hold the glass substrate with the connection film attached as the acceptor substrate on the acceptor stage , so that the distance between the chip part and the connection film is 100 μm.

The laser device uses an excimer laser with an oscillation wavelength of 248 nm. The pulse energy of the laser light is set to 600 J, the flux (fluence) is set to 150 J/cm ² , the pulse width (irradiation time) is set to 30000 picoseconds, and the pulse frequency is set to 0.01 kHz. Set to 1 pulse. The pulse energy of the imaging laser light irradiated to the interface between the anisotropic conductive adhesive layer and the substrate is 0.001~2 J, the flux (fluence) is 0.001~2 J/cm ² , and the pulse width (irradiation time) is 0.01~ 1×10 ⁹ picoseconds, the pulse frequency is 0.1-10000 Hz, and the number of irradiation pulses is 1-30,000,000.

The mask is patterned with an array of openings of a specific size formed at a specific pitch, so that the projection at the interface between the quartz glass as the donor substrate and the release material becomes the shape of the wafer part, ie 30×50 μm.

[Evaluation of Elasticity] Table 3 shows the evaluation results of the wafer component transfer of the connection films 1-7. A total of 100 chip parts were transferred to the bonding film, and the number of chip parts normally bouncing on the bonding film was counted by a microscope. The evaluation of bounce property is based on the ratio of chip components that bounce normally, and the following judgments A to D are made. It is expected to achieve C judgment or above. A: 100% B: More than 98% and less than 100% C: More than 90% and less than 98% D: Less than 90%

[table 3] connective membrane 1 connective membrane 2 connective membrane 3 connective membrane 4 connective membrane 5 connective membrane 6 connective membrane 7 Thickness [μm] 4 4 20 4 4 4 4 Rubber hardness twenty three 31 31 45 8 20 30 200 Hz elastic modulus [MPa] 0.2 10 10 30 0.1 52 27 Modulus of elasticity after hardening [MPa] >2000 >2000 >2000 >2000 >2000 52 27 Evaluation of Elasticity A C B D. D. B B

As shown in Table 3, since the A-type durometer hardness of the connecting film 4 is too large, and the A-type durometer hardness of the connecting film 5 is too small, the transfer rate of the chip parts does not reach 90%. On the other hand, the A-type durometer hardness of connecting films 1-3, 6, and 7 is 20-40, and the storage elastic modulus at a temperature of 30°C and a frequency of 200 Hz is 60 MPa or less. The transfer rate is above 90%.

<5. Second embodiment> In the second embodiment, the chip component and the wiring board are bonded by thermocompression using the connection films 1 to 7 of the first embodiment. In addition, this embodiment is not limited to these.

[Creation of connection structure] Similar to the first embodiment, the chip components were bounced on the connection film of the wiring board, and thermal compression was performed under the conditions of temperature 150°C-pressure 30 MPa-time 30 sec to produce a connection structure. Chip parts (outline 50 μm×50 μm, thickness 150 μm) used TEG (Test Element Group) with 1 pair of electrodes (Cr/Au-plated bump 10 μm×10 μm) installed on the chip part. A glass substrate (thickness 0.5 mm, Ti/Al/Ti pattern 10 μm×10 μm) was used as the wiring board.

[Evaluation of Conductivity] Table 4 shows the evaluation results of the conductivity of the connecting films 1 to 7 .

The conduction resistance was measured through the conduction wiring on the wiring board side. In the evaluation of conductivity, the following judgments of A to D were performed based on the resistance value. It is expected to achieve C judgment or above. A: 50Ω or less B: More than 50 Ω and less than 100 Ω C: More than 100 Ω and less than 200 Ω D: more than 200Ω

[Table 4] connective membrane 1 connective membrane 2 connective membrane 3 connective membrane 4 connective membrane 5 connective membrane 6 connective membrane 7 Thickness [μm] 4 4 20 4 4 4 4 Rubber hardness twenty three 31 31 45 8 20 30 200 Hz elastic modulus [MPa] 0.2 10 10 30 0.1 52 27 Modulus of elasticity after hardening [MPa] >2000 >2000 >2000 >2000 >2000 52 27 Evaluation of Conductivity A A C B C D. D.

As shown in Table 4, since the connection films 6 and 7 are not thermally cured, their conductivity is poor, and it is necessary to provide connection parts such as solder bumps on the chip parts. On the other hand, the storage elastic modulus measured by the tension mode after hardening of the connecting films 1 to 5 is more than 100 MPa, more than 2000 MPa, and good conductivity can be obtained.

10: Chip parts substrate 11: Substrate 12: release material 20: Light emitting element 21: Ontology 22: The first conductivity type electrode 23: The second conductivity type electrode 30: Wiring substrate 31: Substrate 32: 1st electrode 33: 2nd electrode 40: Anisotropic conductive film 50:laser light 60: Anisotropic conductive film substrate 61: Substrate 70: Anisotropic conductive film 70a: Monolithic 72: Monolithic 73: Monolithic 80: Anisotropic conductive film 101:LED 102: transfer printing material 103: Impression material 104:Panel substrate 105: Connecting membrane 111:LED 112: transfer printing material 113: release material 114: Panel substrate 115: connecting membrane T12: Thickness of release material 12 T20: the thickness of the light emitting element 20 T40: the thickness of the anisotropic conductive film 40 W20: Width of light emitting element 20 D: the distance between the light emitting element 20 and the anisotropic conductive film 40

[ Fig. 1 ] is a cross-sectional view schematically showing a state where a light-emitting element provided on a base and an anisotropic conductive film on a wiring board face each other. [FIG. 2] It is an enlarged view showing the connection film on the facing light-emitting element and the wiring board. [ Fig. 3 ] is a cross-sectional view schematically showing a state in which a light-emitting element is transferred and arranged to a specific position on a wiring board by irradiating laser light from the substrate side. [ Fig. 4 ] is a cross-sectional view schematically showing a state in which a light-emitting element is mounted on a wiring board. [ Fig. 5 ] is a cross-sectional view schematically showing a state in which an anisotropic conductive film provided on a base material faces a wiring board. [ Fig. 6 ] is a cross-sectional view schematically showing a state in which a single sheet of an anisotropic conductive film is transferred and arranged to a specific position on a wiring board by irradiating laser light from the substrate side. [ Fig. 7] Fig. 7 is a cross-sectional view schematically showing a state where a light-emitting element provided on a base and an anisotropic conductive film on a wiring board face each other. [ Fig. 8 ] is a cross-sectional view schematically showing a state in which a light-emitting element is transferred and arranged at a specific position on a wiring board by irradiating laser light from the substrate side. [ Fig. 9 ] is a cross-sectional view schematically showing a state in which a light-emitting element is mounted on a single chip arranged at a specific position on a wiring board. [ Fig. 10 ] is a cross-sectional view schematically showing a state in which a single piece of anisotropic conductive film is transferred and arranged on a wiring board in units of electrodes by irradiating laser light from the substrate side. [ Fig. 11 ] is a cross-sectional view schematically showing a state in which a light-emitting element provided on a substrate is opposed to a single sheet transferred and arranged on a wiring board in units of electrodes. [FIG. 12] It is a cross-sectional view schematically showing the state of a single piece in which a laser light is irradiated from the substrate side, and a light-emitting element is bounced and arranged on a corresponding electrode. [ Fig. 13 ] is a cross-sectional view schematically showing a state in which a light-emitting element is mounted on a single piece of a wiring board. [ Fig. 14] Fig. 14 is a cross-sectional view schematically showing a state in which a connection film provided on an electrode surface of a light-emitting element is opposed to a wiring board. [ Fig. 15 ] is a diagram schematically showing mass transfer in the form of an impression. [ Fig. 16 ] is a diagram schematically showing mass transfer by laser method.

10: Chip parts substrate

11: Substrate

12: release material

20: Light emitting element

21: Ontology

22: The first conductivity type electrode

23: The second conductivity type electrode

30: Wiring substrate

31: Substrate

32: 1st electrode

33: 2nd electrode

40: Anisotropic conductive film

Claims (12)

A connecting film, which contains rubber components, has a hardness of 20-40 on a type A durometer, and has a storage elastic modulus of 60 MPa or less at a temperature of 30°C and a frequency of 200 Hz in a dynamic viscoelasticity test using an indentation test device. Such as the connection film of claim 1, which further contains a film-forming resin, a thermosetting resin, a curing agent, and an inorganic filler, and the storage elastic modulus at a temperature of 30°C measured in a tensile mode according to JIS K7244 after curing is: 0.1 GPa or more. The connecting film according to claim 2, which further contains conductive particles, and the conductive particles are arranged in a plane direction. The connection film according to any one of claims 1 to 3, wherein the rubber component is at least one selected from acrylic rubber and silicone rubber. The connecting film according to any one of claims 2 to 4, wherein the thermosetting resin includes an epoxy compound, The aforementioned curing agent is a cationic polymerization initiator. The connection film according to any one of claims 2 to 5, wherein the content of the rubber component is 100 parts by mass of the total of the film-forming resin, the thermosetting resin, the curing agent, the inorganic filler, and the rubber component , being 2 to 10 parts by mass, The content of the inorganic filler is 8 to 12 parts by mass relative to 100 parts by mass of the total of the film-forming resin, the thermosetting resin, the curing agent, the inorganic filler, and the rubber component. A connection film substrate, it has: The connecting film according to any one of Claims 1 to 6; and Substrates that are transparent to laser light. The connection film substrate according to claim 7, wherein a release material is further provided between the connection film and the base material. A method of manufacturing a connected structure, comprising: The step of bouncing, which makes the chip part provided on the base material which is transparent to the laser light and the connection film on the wiring board face, and irradiates the laser light from the side of the above-mentioned base material to make the above-mentioned chip part bouncing on the above-mentioned connection film on; and a connecting step of connecting the above-mentioned chip component to the above-mentioned wiring board; and The above connecting film contains rubber components, the A-type durometer hardness is 20-40, and the storage modulus of elasticity at a temperature of 30°C and a frequency of 200 Hz is 60 MPa or less. The method for manufacturing a bonded structure according to claim 9, which further includes a transfer step in which the connection film provided on the base material transparent to laser light faces the wiring board, from the side of the base material irradiating laser light to transfer a single piece of the above-mentioned connecting film onto the above-mentioned wiring board, In the above-mentioned step of bouncing, the above-mentioned chip part is bouncing on the single piece of the above-mentioned connecting film. The method for manufacturing a bonded structure according to claim 9, which further includes a transfer step in which the connection film provided on the base material transparent to laser light faces the wiring board, from the side of the base material By irradiating laser light, a single piece of the above-mentioned connection film is transferred onto the above-mentioned wiring board in units of electrodes, In the above step of bouncing, the above-mentioned chip parts are bouncing on the single piece of the corresponding electrode. A method of manufacturing a connected structure, comprising: The step of bouncing, which makes the connection film provided on the electrode surface of the chip part of the base material which is transparent to laser light and the wiring board face, and irradiates the laser light from the side of the above-mentioned base material so that the above-mentioned chip part is separated from the above-mentioned The connection film is bounced on the above-mentioned wiring substrate; and a connecting step of connecting the above-mentioned chip component to the above-mentioned wiring board; and The above connecting film contains rubber components, the A-type durometer hardness is 20-40, and the storage modulus of elasticity at a temperature of 30°C and a frequency of 200 Hz is 60 MPa or less.

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