JPH11135925A - Mounting method of electronic component and transferring method of conductive particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component mounting method and a conductive particle transfer method, wherein an electronic component is reliably mounted on a board surely interposing conductive particles between the bump of a chip electrode and the joint of a board electrode to surely and electrically connect these electrodes together and improving the adjacent terminals in insulating properties between them an electronic component such as a bare chip of fine pitch and the like is mounted on a wiring board through a flip chip mounting method. SOLUTION: Conductive adhesive agent 13 is applied to a bump 12 formed on the chip electrode 11 of a semiconductor bare chip 10, conductive particles 14 are attached to the bump 12, and the semiconductor base chip 10 is bonded to the bare chip mounting part of a wiring board 20 by thermocompression. At this thermocompression bonding, the conductive particles 14 attached to the joint surface of the bump 12 by applying the conductive adhesive agent 13 to the bump 12 are buried in both the bump 12 and the pad 21 biting into them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting electronic components and a method for transferring conductive particles which are suitable for mounting electronic components having a narrow-pitch multi-electrode structure such as a semiconductor bare chip on a wiring board.

[0002]

2. Description of the Related Art As an electronic component mounting technology for mounting a multi-electrode electronic component such as a semiconductor chip on a wiring board, ACF is known.
There is a circuit (electrode) joining means using an anisotropic conductive film called (Anisotropic Conductive Film).

[0003] However, in this type of ACF, conductive particles are randomly dispersed in an anisotropic conductive sheet.
Since the density of the conductive particles varies depending on the position of the sheet, the conductive particles contained in the anisotropic conductive sheet are bonded to the electrodes of the electronic component and the electrodes of the wiring board during heating and pressing during mounting. There is a problem in that it may come off from the part, and high electrical reliability cannot be obtained. This problem was more remarkable particularly in the mounting of electronic components having a narrow pitch multi-electrode structure such as a semiconductor bare chip.

FIG. 9 shows an example of this. Here, a conductive sheet 95 is interposed between the wiring board 93 and the electronic component 91, and when the electronic component 91 is mounted on the wiring board 93 by thermocompression bonding, the conductive particles 96 in the conductive sheet 95 are pressed by pressure.
Escapes from the joint surface between the substrate electrode 94 and the component electrode 92, and the conductive particles 96 in the conductive sheet 95 are not embedded between the substrate electrode 94 and the component electrode 92 in an occlusal state. Not electrically coupled to each other, causing a decrease in electrical resistance at the junction and a decrease in reliability due to circuit instability, etc., and a decrease in electrical insulation due to the presence of many unnecessary conductive particles between adjacent electrodes. There was a problem of inviting. In the drawing, reference numeral 97 denotes an insulating adhesive in the conductive sheet 95.

[0005]

As described above, in the conventional ACF, the conductive particles are randomly dispersed in the anisotropic conductive sheet, and the density of the conductive particles varies depending on the position of the sheet. Therefore, the conductive particles contained in the anisotropic conductive sheet, during mounting, heating,
At the time of pressurization, it may come off from the joint between the electrode of the electronic component and the electrode of the wiring board. Therefore, the electric resistance of the joint decreases, the reliability decreases due to circuit instability, etc. However, the presence of unnecessary conductive particles causes a decrease in electrical insulation, and there is a problem that high electrical reliability cannot be obtained. This bug is
In particular, in the mounting of electronic parts having a narrow pitch multi-electrode structure, such as a semiconductor bare chip, it was more remarkable.

The present invention has been made in view of the above circumstances,
In particular, when mounting electronic components such as bare chips by a flip chip method, which has a fine pitch, for example, by reliably interposing conductive particles at the junction between the chip electrode side bump and the substrate electrode, the electrical connection between the electrodes is ensured, It is another object of the present invention to provide a method for mounting an electronic component and a method for transferring conductive particles, which make it possible to mount a highly reliable electronic component by improving electrical insulation between adjacent terminals.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to prevent conductive particles from escaping from a junction between a chip electrode-side bump and a substrate electrode, particularly when mounting electronic components such as bare chips by a flip chip method with a fine pitch. By transferring or attaching the conductive particles only to the tip of the bump in advance, and then bonding and sealing the bump and the substrate electrode with an insulating resin mainly composed of an epoxy resin, a curing agent, or the like. By preventing the conductive particles from escaping, and by eliminating unnecessary conductive particles between adjacent terminals, the electrical connection between the electrodes is ensured, and the electrical insulation between the adjacent terminals is improved.
It is characterized by enabling mounting of highly reliable electronic components.

That is, the present invention relates to a method of mounting an electronic component having a narrow-pitch multi-electrode structure, such as a semiconductor bare chip, on a wiring board, wherein a bump is formed on an electrode of the electronic component. A step A of attaching conductive particles to the tip of the bump; a step B of attaching a thermosetting film to an electronic component mounting surface of the wiring board; and an electronic component passing through the step A on the wiring board passing through the step B. The electronic component is mounted on the wiring board by the step C of mounting by thermocompression bonding.

The present invention also relates to a method for mounting a semiconductor bare chip, a step A of attaching conductive particles to tips of bumps formed on electrodes of the semiconductor bare chip, and a wiring board on which the semiconductor bare chip is mounted. Mounting a semiconductor bare chip on a wiring board by performing a step B of attaching a thermosetting film to the mounting surface of step A and a step C of mounting the semiconductor bare chip having undergone step A on the wiring board having undergone step B by thermocompression bonding. It is characterized by.

Further, the present invention provides a method for transferring conductive particles, wherein a thin film-like anisotropic conductive film in which fine conductive particles having a particle size of 3 μm or less are embedded is formed on a bump formed on an electrode of an electronic component. The method is characterized in that the thin-film anisotropic conductive film is transferred only to the surface of the tip of the bump by pressing or thermocompression bonding.

The present invention also relates to a method for transferring conductive particles, wherein fine conductive particles having a particle size of 3 μm or less are pasted in a solvent such as a glycol-based high-boiling solvent and the thickness is reduced to 10 μm or less by squeezing. After controlling the thin film, the bumps formed on the electrodes of the electronic component are pressed from above, and the conductive particles are transferred only to the tips of the bumps formed on the electrodes of the electronic component by heating. And

The present invention also relates to a method for mounting an electronic component having a narrow-pitch multi-electrode structure, such as a semiconductor bare chip, on a wiring board, comprising a thin film having fine conductive particles having a particle size of 3 μm or less embedded therein. On the anisotropic conductive film,
The bump formed on the electrode of the electronic component is pressed or thermocompressed, the thin anisotropic conductive film is transferred only on the surface of the bump tip, and the electronic component is thermocompressed to the wiring board via the film. It is characterized by implementation.

The present invention also relates to a method for mounting an electronic component having a narrow-pitch multi-electrode structure, such as a semiconductor bare chip, on a wiring board. Into a paste in a solvent, and control the thin film to a thickness of 10 μm or less by squeezing, press the bump formed on the electrode of the electronic component from above, and transfer the paste-like fine conductive particles to the bump. Thereafter, the electronic component is mounted on the wiring board by thermocompression bonding.

According to the present invention, there is provided the electronic component mounting method as described above, wherein between the bump formed on the electrode of the electronic component and the electrode portion of the wiring board, an insulating resin mainly composed of an epoxy resin and a curing agent is provided. By applying a conductive resin, or by thermocompression bonding between electrodes through an insulating resin film, the transferred conductive particles reinforce the joint and maintain the insulation between adjacent electrodes. I do.

According to the above-described method of the present invention, first, conductive particles are adhered only to the electrode-side tip portion of the electronic component by transfer or coating, and then, adhered by an insulating resin.
By performing the sealing, it is possible to prevent the conductive particles from flowing out from the electrode joint portion, and to ensure the electrical connection between the electrodes. In addition, since the conductive particles are adhered only to the electrode-side tip and pressure-bonded, unnecessary conductive particles existing between adjacent electrodes are reduced, and high insulation between adjacent electrodes is maintained. This makes it possible to mount electrically stable and highly reliable electronic components.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show the first embodiment of the present invention, respectively.
FIG. 1 is a view for explaining an embodiment, FIG. 1 is a view showing a pre-process of a semiconductor bare chip to be mounted, and FIG.
FIG. 3 is a diagram showing a specific example of the process shown in FIG. 3D, FIG. 3 is a diagram showing a pre-process of a wiring board on which the semiconductor bare chip shown in FIG. 1 is mounted, and FIG. FIG. 7 is a diagram showing a process of mounting (thermocompression bonding) on the wiring board after the process shown in FIG. 5 and a state of a main part after the mounting.

In FIGS. 1 to 4, reference numeral 10 denotes an electronic component having a narrow-pitch multi-electrode structure to be mounted. Here, a semiconductor bare chip is mounted. Reference numeral 11 denotes electrodes (chip electrodes) provided on the semiconductor bare chip 10, which are actually arranged in large numbers, but are omitted here and only two are shown. Reference numeral 12 denotes a bump formed on the chip electrode 11 and made of, for example, Au, Ni, a solder alloy, or the like. Reference numeral 13 denotes a paste-like conductive adhesive applied (for example, applied) on the substrate electrode bonding surface of the bump 12.

Reference numeral 14 denotes conductive particles made of hard fine metal particles such as nickel, for example, for connecting the circuit between the electrodes of the semiconductor bare chip 10 and the wiring board, and the bumps are formed by the conductive adhesive 13 applied to the bumps 12. 12 are buried in a state of being engaged between the bump 12 and the substrate electrode by pressure during thermocompression bonding.

Reference numeral 15 denotes a transfer stage for adhering a plurality of conductive particles 14 to each of the bumps 12 formed on the chip electrodes 11 of the semiconductor bare chip 10. Each of the transfer stages 15 has a conductive adhesive 13 applied thereto. A plurality of conductive particles 14 are attached to the tips, respectively.

Reference numeral 20 denotes a wiring board on which the semiconductor bare chip 10 having the bumps 12 formed on the chip electrodes 11 is mounted. Reference numeral 21 denotes pads (substrate electrodes) provided on the bare chip mounting surface on the wiring board 20.

Reference numeral 30 denotes a thermosetting film stretched on the component mounting surface of the wiring board 20, which is melted during the thermocompression bonding step and fills a gap between the semiconductor bare chip 10 and the wiring board 20 so that the semiconductor bare chip 10 is bonded to the wiring board 20. 20. Here, a material equivalent to an ACF excluding dissolved conductive particles can be used.

A method of transferring conductive particles and mounting a semiconductor bare chip according to the first embodiment of the present invention will now be described with reference to FIGS. First, with reference to FIG. 1, the pre-process of the semiconductor bare chip 10 to be mounted will be described.

In this pre-process, after the bumps 12 are formed on the chip electrodes 11, the conductive adhesive 1 is applied to the bumps 12.
3 and apply the conductive adhesive 13 to the bumps 12.
A plurality of conductive particles 14 are adhered to the tip of.

That is, as shown in FIG. 1B, on the chip electrode 11 of the semiconductor bare chip 10 shown in FIG.
The bump 12 is formed. Next, as shown in FIG. 1C, the conductive adhesive 1
3 is applied. Thereafter, as shown in FIG. 1D, a plurality of conductive particles 14 are attached to the substrate electrode bonding surface of the bump 12 to which the conductive adhesive 13 has been applied.

FIG. 2 shows an example of the conductive particle attaching step at this time. Here, as shown in FIGS. 2A to 2C, a semiconductor bare chip 10 in which a conductive adhesive 13 is applied to a bump 12 formed on a chip electrode 11 is supplied to a transfer stage 15, and a large number of semiconductor bare chips 10 are provided. On the transfer stage 15 in which the conductive particles 14 are uniformly dispersed, the conductive particles 1
4 is deposited. As a result, a plurality of conductive particles 14 are provided on each of the bumps 12 formed on the chip electrode 11.
Is adhered by the conductive adhesive 13.

A pre-process for the wiring board 20 as shown in FIG. 3 is performed separately from the pre-process for the semiconductor bare chip 10. Here, as shown in FIGS. 3A and 3B, the thermosetting film 30 is attached to the bare chip mounting surface of the wiring board 20.

After performing the pre-process on each of the semiconductor bare chip 10 and the wiring board 20 as described above,
As shown in (a), the semiconductor bare chip 10 is thermocompression-bonded to the bare chip mounting portion of the bare chip of the wiring board 20.

As shown in FIG. 4B, a plurality of conductive particles adhered on the bonding surface of the bump 12 by the conductive adhesive 13 applied to the bump 12 by the pressure during the thermocompression bonding. 14 is embedded between the bump 12 and the pad 21 in an occlusal state.

Further, at this time, the thermosetting film 30 stretched on the component mounting surface of the wiring board 20 melts and fills the gap between the semiconductor bare chip 10 and the wiring board 20 to fix the semiconductor bare chip 10 to the wiring board 20. .

As described above, by directly fixing the conductive particles 14 to the bumps 12 with the conductive adhesive 13, when the semiconductor bare chip 10 is mounted, the conductive particles 14 are located between the bumps 12 and the pads 21 of the wiring board 20. Inconveniences such as a decrease in electric resistance of the inter-electrode junction and instability of the circuit due to the absence of 14 can be reliably avoided, and stable and reliable component mounting becomes possible. ACF according to the prior art
Since the conductive particles are not randomly dispersed as in
As a drawback of CF, there is no conductive particles between electrodes to be connected to a circuit, and it is possible to reliably avoid a decrease in electrical insulation due to the presence of many unnecessary conductive particles between adjacent electrodes. High reliability can be ensured.

Next, a second embodiment of the present invention will be described with reference to FIGS. Here, a method of mounting a bare chip by a flip chip method is shown. 5 and 6, reference numeral 40 denotes an electronic component having a narrow pitch multi-electrode structure to be mounted, and here, a semiconductor bare chip is to be mounted. Reference numeral 41 denotes electrodes (chip electrodes) provided on the semiconductor bare chip 40, which are actually arranged in large numbers, but are omitted here and only two are shown. Reference numeral 42 denotes a bump formed on the chip electrode 41 and made of, for example, Au, Ni, a solder alloy, or the like.

Reference numeral 50 denotes a thin film anisotropic member having a thickness of about 5 μm in which a large number of conductive particles 51 made of hard fine metal particles having a particle diameter of about 2 to 3 μm are embedded for circuit coupling between the electrodes of the semiconductor bare chip 40 and the wiring board. A conductive film that is adhered to the electrode joining surface of the bump 42 by, for example, thermocompression bonding.

Here, the particle size of the conductive particles 51 is
(2) The height is smaller than the height (h) of the tip portion (electrode joining surface portion 42a). Also, by making the thickness of the anisotropic conductive film 50 as close as possible to the particle size of the conductive particles 51,
The escape of the conductive particles 51 when pressing the tip of the bump 42 (the electrode joining surface 42a) is prevented.

Reference numeral 60 denotes a wiring board on which the semiconductor bare chip 40 having the bumps 42 formed on the chip electrodes 41 is mounted. Reference numeral 61 denotes a pad (substrate electrode) provided on the bare chip mounting surface on the wiring substrate 60.

Reference numeral 63 denotes an insulating resin film provided on the bare chip mounting surface of the wiring board 60 and containing an epoxy resin, a curing agent, or the like as a main component. Maintain the insulation properties of

Here, a method for mounting a bare chip according to the second embodiment of the present invention will be described with reference to FIGS. First, a particle diameter of 2 to 3 μm is applied to the electrode joining surface of the bump 42 formed on the chip electrode 41 of the semiconductor bare chip 40.
A thin film-like anisotropic conductive film 50 having a thickness of about 5 μm in which conductive particles 51 of about 5 μm are embedded is transferred. FIG. 5A shows a semiconductor bare chip 40 to be mounted at this time, and FIG. 5B shows a state where the anisotropic conductive film 50 is transferred to the bumps 42 of the semiconductor bare chip 40.

Thereafter, an insulating resin film 63 is interposed between the bump 42 formed on the chip electrode 41 of the semiconductor bare chip 40 and the substrate electrode 61 of the wiring board 60, and the semiconductor bare chip 40 is Thermocompression bonding to bare chip mounting surface. This strengthens the electrode joint,
In addition, insulation between adjacent electrodes is maintained. FIG. 6A shows a state in which an insulating resin film 63 is interposed between the bumps 42 formed on the chip electrodes 41 of the semiconductor bare chip 40 and the substrate electrodes 61 of the wiring board 60 at this time. FIG. 6B shows a state in which the pressure is applied.

In place of the insulating resin film 63,
A paste-like thermosetting insulating resin material may be applied.
As described above, the tip portion of the bump 42 (the electrode joining surface portion 42a)
The semiconductor bare chip 40 is attached to the wiring board 6 by attaching conductive particles 51 to the
0, a plurality of conductive particles are reliably secured between the bump 42 and the pad 61 of the wiring board 60,
Stabilization of the electrical resistance between the electrode junctions and improvement of long-term reliability can be achieved.

Also, the tip of the bump (electrode bonding surface 42)
Since the conductive particles 51 can be reliably transferred only to a), the conductive particles 51 can be transferred from between the bumps 42 formed on the chip electrodes 41 of the semiconductor bare chip 40 and the wiring board 60.
In addition to avoiding the disadvantage of flowing out, a plurality of conductive particles can be reliably embedded between the electrode joints, and unnecessary conductive particles between adjacent electrodes can be eliminated. Connection can be reliably performed, and insulation between adjacent electrodes can be improved.

Next, a third embodiment of the present invention will be described with reference to FIGS. Here, a method of mounting a bare chip by a flip chip method is shown, and FIGS.
The same reference numerals are given to the same parts as the second embodiment shown in FIG.
The description is omitted.

In the third embodiment, conductive particles 71 having a particle size of about 2 to 3 μm are mixed with a high boiling solvent 70 such as a glycol-based solvent.
Is used as a solvent to form a paste, the thin film is controlled to a thickness of about 5 to 10 μm by squeezing, and then the bumps 4 formed on the chip electrodes 41 of the semiconductor bare chip 40 are formed.
By attaching a plurality of paste-like conductive particles 71 to the second electrode bonding surface 42a, the plurality of conductive particles 71 are transferred to the electrode bonding surface of the bump 42. FIG. 7A shows a state in which the paste-like conductive particles 71 are attached to the electrode joining surface 42a at this time, and FIG. 7 shows a state in which the conductive particles 71 are attached to the electrode joining surface 42a of the bump 42.
This is shown in FIG. In the third embodiment as well, the particle size of the conductive particles 71 is smaller than the height (h) of the tip of the bump 42 (the electrode joining surface 42a). In addition, by making the thickness at the time of squeezing as close as possible to the particle size of the conductive particles 71, the escape of the conductive particles 71 when pressing the tip portion (electrode bonding surface portion 42a) of the bump 42 is prevented. I have to.

Further, in this embodiment, since the high-boiling solvent 70 is used to make the conductive particles 71 into a paste, volatilization at room temperature is small, and residue is generated by heating at the time of thermocompression bonding to the bumps 42. Can be eliminated.

Thereafter, a paste-like resin 80 having an insulating property mainly composed of an epoxy resin, a curing agent and the like is applied to the bare chip mounting surface of the wiring board 60, and is formed on the chip electrodes 41 of the semiconductor bare chip 40. Thermocompression bonding is performed between the bump 42 and the pad (substrate electrode) 61 of the wiring board 60. This achieves reinforcement of the electrode joint and retention of insulation between adjacent electrodes. The state before the thermocompression bonding at this time is shown in FIG.
FIG. 8A shows the state after thermocompression bonding, and FIG.

It should be noted that a resin film can be used instead of the above-mentioned paste-like resin 80. By directly fixing the conductive particles 71 to the tip portions (electrode bonding surface portions 42a) of the bumps 42, when the semiconductor bare chip 40 is mounted on the wiring board 60, the gap between the bumps 42 and the pads 61 of the wiring board 60 is reduced. In addition, a plurality of conductive particles are reliably ensured, thereby stabilizing the electrical resistance between the electrode joints and improving long-term reliability.

Further, the tip portion of the bump (electrode bonding surface portion 42)
Since the conductive particles 71 can be reliably transferred only to a), the conductive particles 71 can be transferred between the bumps 42 formed on the chip electrodes 41 of the semiconductor bare chip 40 and the wiring board 60.
In addition to avoiding the disadvantage of flowing out, a plurality of conductive particles can be reliably embedded between the electrode joints, and unnecessary conductive particles between adjacent electrodes can be eliminated. Connection can be reliably performed, and insulation between adjacent electrodes can be improved.

[0046]

As described above in detail, according to the present invention, especially when electronic components such as bare chips are mounted at a fine pitch, for example, by a flip chip method, the bonding between the bumps on the chip electrode side and the substrate electrodes is surely performed. With conductive particles interposed,
Provided are a method for mounting an electronic component and a method for transferring conductive particles, which make it possible to reliably mount an electronic component by reliably and electrically connecting electrodes and improving electrical insulation between adjacent terminals. it can.

[Brief description of the drawings]

FIG. 1 is a view showing a pre-process of a semiconductor bare chip in a first embodiment of the present invention.

FIG. 2 is a view showing a specific example of the step shown in FIG. 1D in the first embodiment of the present invention.

FIG. 3 is a diagram showing a pre-process of a wiring board in the first embodiment of the present invention.

FIG. 4 is a diagram showing a process of mounting (thermocompression bonding) a semiconductor bare chip on a wiring board and a state of a main part after the mounting in the first embodiment of the present invention.

FIG. 5 is a diagram showing a pre-process of a semiconductor bare chip in a second embodiment of the present invention.

FIG. 6 is a view showing a process of mounting (thermocompression bonding) a semiconductor bare chip on a wiring board and a state of a main part after the mounting in the second embodiment of the present invention.

FIG. 7 is a view showing a pre-process of a semiconductor bare chip in a third embodiment of the present invention.

FIG. 8 is a diagram illustrating a process of mounting (thermocompression bonding) a semiconductor bare chip on a wiring board and a state of a main part after the mounting according to the third embodiment of the present invention.

FIG. 9 is a view for explaining a component mounting method using a conventional ACF technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Electronic component (semiconductor bare chip) of a narrow pitch multi-electrode structure, 11 ... Electrode (chip electrode) provided on semiconductor bare chip 10, 12 ... Bump formed on chip electrode 11, 13 ... Paste-like conductive adhesive 14 ... conductive particles, 15 ... transfer stage, 20 ... wiring board, 21 ... pad (substrate electrode), 30 ... thermosetting film, 40 ... electronic component (semiconductor bare chip) with narrow pitch multi-electrode structure, 41 ... semiconductor An electrode (chip electrode) provided on the bare chip 40; 42, a bump formed on the chip electrode 41; 42a, an electrode bonding surface; 50, a thin anisotropic conductive film; 51, conductive particles; 61: Pad (substrate electrode) 63: Insulating resin film 70: High boiling point solvent for forming conductive particles 71 into paste, 71: Conductive particles 80: Paste resin.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichi Murakami 2-9-9 Suehirocho, Ome-shi, Tokyo Inside the Toshiba Ome Plant (72) Inventor Hidenori Tanaka 1381-1, Shinmachi, Ome-shi, Tokyo Toshiba Computer Data Engineering Co., Ltd. (72) Inventor Kuniyasu Hosoda 1381 Shinmachi, Ome-shi, Tokyo Toshiba Computer Engineering Co., Ltd.

Claims (8)

[Claims] An electronic component mounting method for mounting an electronic component having a narrow-pitch multi-electrode structure on a wiring board, wherein a bump is formed on an electrode of the electronic component, and conductive particles are attached to a tip of the bump. A step A of bonding, a step B of attaching a thermosetting film to an electronic component mounting surface of the wiring board, and a step C of mounting the electronic component having undergone the step A on the wiring board having undergone the step B by thermocompression bonding. A method for mounting an electronic component, comprising mounting the electronic component on a wiring board. 2. A step of attaching conductive particles to the tip of a bump formed on an electrode of a semiconductor bare chip, and a B step of attaching a thermosetting film to a mounting surface of a wiring board on which the semiconductor bare chip is mounted. A method for mounting a semiconductor bare chip on a wiring board, comprising: a step C of mounting the semiconductor bare chip after the step A on the wiring board after the step B by thermocompression bonding. 3. A pressure-sensitive or thermocompression-bonded thin film-like anisotropic conductive film in which fine conductive particles having a particle size of 3 μm or less are embedded is pressed onto a bump formed on an electrode of an electronic component, and the surface of the tip of the bump is pressed. A method for transferring conductive particles, comprising transferring a thin-film anisotropic conductive film only to the conductive particles. 4. A method in which fine conductive particles having a particle size of 3 μm or less are made into a paste in a solvent such as a glycol-based high-boiling solvent and thinned to a thickness of 10 μm or less by squeezing. A method for transferring conductive particles, wherein a conductive particle is transferred only to a tip portion of a bump formed on an electrode of an electronic component by pressing and heating a bump formed on the electrode. 5. An electronic component mounting method for mounting an electronic component having a narrow pitch multi-electrode structure on a wiring board, comprising: a thin film-like anisotropic conductive film in which fine conductive particles having a particle size of 3 μm or less are embedded; The bump formed on the electrode of the electronic component is pressed or thermocompressed, the thin anisotropic conductive film is transferred only on the surface of the bump tip, and the electronic component is thermocompressed to the wiring board via the film. An electronic component mounting method characterized by mounting. 6. A method of mounting an electronic component having a narrow-pitch multi-electrode structure on a wiring board, comprising: forming fine conductive particles having a particle size of 3 μm or less into a paste using a high-boiling solvent as a solvent; The thin film is controlled to a thickness of 10 μm or less by zing, and the bumps formed on the electrodes of the electronic component are pressed from above to transfer the fine paste conductive particles to the bumps. An electronic component mounting method characterized by mounting by crimping. 7. An insulating resin film containing an epoxy resin or a hardening agent as a main component is applied between a bump formed on an electrode of an electronic component and an electrode portion of a wiring board. By thermocompression between the electrodes via
7. The method of mounting an electronic component according to claim 5, wherein the transferred conductive particles reinforce the joint and maintain insulation between adjacent electrodes. 8. The method for mounting an electronic component according to claim 5, wherein a semiconductor bare chip is used as the electronic component.