JP2001015555A - Method for mounting bare ic chip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make simple the manufacturing process of mechanical equipment or a wiring board constituted by mounting a bare IC chip on a circuit, by emitting electromagnetic waves upon the bare IC chip from the side opposite to the arranging side of the chip while the chip is press-contacted with a base material. SOLUTION: A circuit 1 is formed on a base material 2, and an insulating adhering section 5 for the terminals 3 of a bare IC chip 3 is formed by printing an insulating adhesive substance B. Then terminal adhering sections 6 are formed in the circuit 1 so that the sections 6 may necessarily come into contact with the terminals 4 of the chip 3, by printing a conductive adhesive substance A until thicknesses of the sections 6 become thicker than that of the section 5. Thereafter, the chip 3 is placed on the base material 2 by aligning the chip 3 with the insulating adhering section 4 and terminal adhering sections 6 and press-contacted with the material 2. While the chip 3 is press-contacted with the material 3, electromagnetic waves are emitted upon the chip 3 from the side opposite to the arranging side of the chip 3. Thus, the chi 3 is mounted on the circuit 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC which can be connected to a circuit board or the like even in the case of an IC bare chip in which bumps are not formed in the terminal portion in advance, so that reliable connection can be made.
The present invention relates to a method for mounting a bare chip, for example, RF-ID including formation of an antenna of a non-contact IC tag.
(Radio Frequency IDentifi
The present invention relates to a method of mounting an IC bare chip that can be used for equipment for use, printed wiring boards for various electric devices, and the like.

[0002]

Conventionally, when mounting an IC bare chip on a circuit, it is necessary to previously form bumps on terminal portions of the IC bare chip. An IC bare chip was mounted on the circuit. For this reason, there are problems that processing costs are increased due to the increase in the number of steps, and that the yield of circuit connection is affected by whether or not the bumps are formed stably. In addition, the current bump formation method has a drawback that it is difficult to improve connection reliability because the height and width of the bump are not always constant. In view of the above, an object of the present invention is to make it possible to mount an IC bare chip on a circuit without previously providing bumps on a terminal portion of the IC bare chip when mounting the IC bare chip on the circuit. It is an object of the present invention to simplify the manufacturing process and reduce the cost.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has been described in which a base material on which a circuit is formed in advance is provided.
A conductive adhesive substance is applied to a connection portion of the IC bare chip with a terminal by a printing method, and the terminal is arranged on the base material so that the terminal corresponds to the application part of the conductive adhesive substance, and the base material of the IC bare chip is provided. The electromagnetic wave is irradiated from the side opposite to the side on which the IC bare chip is arranged at the time of crimping to the IC.
An object of the present invention is to provide a method for mounting a C bare chip to solve the above-mentioned problem.

[0004]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on embodiments. That is, the present invention relates to a mounting position where an IC bare chip is to be arranged on a substrate,
On the substrate on which the circuit is formed, on the circuit terminal portion corresponding to the terminal of the IC bare chip, a conductive adhesive material (A)
Is formed by printing an adhesive material (B) having an insulating property on a portion corresponding to a portion of the IC bare chip having no terminal, and applying an electromagnetic wave from the back surface of the base material while pressing the IC bare chip from above. Then, the position of the IC bare chip is fixed and the connection reliability is obtained.

[0005] First, as a base material, a woven fabric, a nonwoven fabric, a mat, a paper made of inorganic or organic fibers such as glass fiber, alumina fiber, polyester fiber, polyamide fiber or the like, or a combination thereof, or a resin varnish is used. Impregnated and molded composite substrate, polyamide resin substrate, polyester resin substrate, polypropylene resin substrate, polyimide resin substrate, ethylene vinyl alcohol copolymer substrate, polyvinyl alcohol resin substrate,
Plastic substrates such as polyvinyl chloride-based resin substrates, polyvinylidene chloride-based resin substrates, polystyrene-based resin substrates, polycarbonate-based resin substrates, acrylonitrile-butadiene-styrene copolymer-based resin substrates, and polyethersulfone-based resin substrates Alternatively, known materials such as those subjected to surface treatment such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, flame plasma treatment, and ozone treatment can be used. The circuit formation on the substrate can be performed by a known method such as metal etching, metal winding welding, metal vapor deposition film transfer, metal thin film tape sticking, and conductive paste printing.

[0006] The conductive adhesive material (A) and the insulating adhesive material (B) used in the method of the present invention hardly emit volatile components at the time of pressing, and exhibit good adhesion to the IC bare chip after heat treatment. It is selected from those that maintain reliability after mounting, for example, impact resistance, water resistance, moisture resistance, heat resistance, and the like. From the viewpoint of shape retention, those having a crosslinked structure or those forming a crosslinked structure by heat treatment are preferred. Since the conductive adhesive substance (A) assures conductive connectivity with the terminals of the IC bare chip, the conductive adhesive substance (A) contains conductive particles and a resin serving as a binder as essential components. It is preferable to use a conductive paste that has both strong adhesion to the metal of the terminal. A typical example of the conductive particles is a metal powder, especially a silver powder. Conductive metals other than silver, such as gold, platinum, copper,
Nickel, cobalt, palladium, rhodium, or the like may be used. The insulating adhesive substance (B) is formed by bonding
It has the function of fixing the position of the C bare chip, preventing short-circuiting between the conductive connection parts, and protecting the conductive connection parts from external impact. It is preferable to include a resin that is high, has excellent insulation properties, and can absorb stress and strain caused by thermal shock and physical shock. When insulation is not easily achieved by the resin alone, an insulating filler such as silica, alumina, glass, talc, rubber, and the like may be added.

As a resin which is an essential component of the conductive adhesive substance (A) or the insulating adhesive substance (B), a known thermoplastic resin or cross-linkable resin, or both can be used. Thermoplastic resin, for example, polyethylene,
Polypropylene, polystyrene, ABS resin, polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl alcohol, polyacetal, polycarbonate, polyester, polyphenylene oxide, polysulfone, polyimide, polyethersulfone, polyarylate, poly Examples thereof include ether ether ketone, polytetrafluoroethylene, and silicone resin, and one kind or a combination of two or more kinds is also possible, but not limited thereto.

The crosslinkable resin composition is selected from those which react so as not to generate volatile components during curing. Examples thereof include: (1) a glycidylated product of bisphenol A or bisphenol F, or 3,4-epoxycyclohexylmethyl-
Liquid epoxy resin represented by 3,4-epoxycyclohexylcarboxylate, amino compound, phenol compound, acid anhydride compound, organic acid compound or onium salt compound (2) 1,1-bis (4-cyanate (3) a bismaleimide or an addition polymer of bismaleimide and a diamine compound, an amino compound, an allyl compound or a radical generator (4) diallyl Liquid allyl compound represented by phthalate, amino compound or radical generator (5) triallyl isocyanurate or triallyl cyanurate, amino compound or peroxide (6) Polyethylene glycol, hexamethylene glycol, glycerin Polyvalent active hydrogen And compounds,
Isocyanate compound (7) Liquid acrylate compound represented by polyethylene glycol diacrylate, trimethylolpropane alkylene oxide-modified triacrylate, etc., radical generator (8) Vinyl group-containing liquid polyolefin, and radical generator (9) Vinyl silane compound And a compound having a SiH group, and a thermosetting resin composition such as a platinum catalyst, or a photoinitiator that generates free radical active species or cation active species by light radiation (for example, those that generate free radical active species include: Benzophenone derivative, thioxanthone derivative, anthraquinone derivative, trichloromethyltriazine derivative, acylphosphine oxide derivative, α-hydroxyketone derivative, α-aminoketone derivative, benzoin derivative, pendiyne Luketal derivatives,
An acridine derivative, a carbazole-phenone derivative, or a combination thereof is preferable, and an aromatic sulfonium salt compound, an aromatic iodonium salt compound, or a combination thereof is preferable as a compound generating a cationic active species. ) And a photoreactive resin having a functional group that reacts with those active species (for example, an acrylate compound and a methacrylate compound are preferable as those reacting with a free radical species, and an alicyclic compound is preferable as a compound reacting with a cationic active species). Formula epoxy compounds, oxetane compounds, alkene oxide compounds, glycidyl ether compounds, and vinyl ether compounds are preferable. In any case, two or more of them may be used in combination.)
The compounded photocurable resin composition can be used.

The conductive adhesive substance (A) and the insulating adhesive substance (B) may contain a solvent if it can be removed before the IC bare chip is pressed. Known additives can be used as the additive solvent. However, the boiling point is preferably 250 ° C. or lower to avoid remaining in the system after the curing reaction. For example, hydrocarbon solvents such as toluene, cyclohexane, methylcyclohexane, n-hexane, and pentane; alcohols such as isopropyl alcohol and butyl alcohol; ketones such as cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, and isophorone. , Ethyl acetate, propyl acetate, esters such as butyl acetate, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, 3-methoxy-3
Glycol monoethers such as -methylbutyl acetate and acetates thereof, and one or more of the above-mentioned solvents are used as a mixed system.

Further, before mounting the IC bare chip, it may be placed in a semi-cured state by heating, electromagnetic wave irradiation, electron beam irradiation, or the like. In addition, release agents,
Known additives such as a surface treatment agent, a filler, a pigment, and a dye may be added. Examples of the release agent include waxes and zinc stearate, and examples of the surface treatment agent include a silane coupling agent. Examples of the filler include silica, alumina, talc, clay and the like.

The conductive adhesive material (A) and the insulating adhesive material (B) may be in the form of a uniform varnish by mixing the respective components, or may be a known suitable material such as a kneader or a three-roll. It is obtained by kneading and uniformly dispersing by a suitable method, and is adjusted to be a viscous liquid in a temperature range in which the base material does not deteriorate during printing. This is applied on the substrate after circuit formation by a printing method. The printing method is performed by a known method, and a screen printing method is particularly desirable. Further, these adhesive substances (A) and (B) are used under the final crimping condition at the time of chip mounting, preferably within a time range of 0.1 to 30 seconds and within a pressure range of 0.1 to 0.5 MPa. The reactivity is adjusted so that the connection of the IC bare chip is fixed by irradiating an electromagnetic wave from the back side of the IC bare chip mounting substrate surface.

Next, an example of a mounting method will be specifically described with reference to the drawings. First, with respect to the mounting position A of the IC bare chip 3 on the substrate 2 on which the circuit 1 is formed on the surface,
Perform (a), (b), (c), (d), and (e). (A) A circuit 1 is formed on a substrate 2 (FIG. 1 (A)). (B) Except for the portion where the terminals 4 (here, two places) of the IC bare chip 3 are applied, the insulating adhesive portion 5 is applied and formed by printing using the insulating adhesive material (B) (FIG. 1).
(B)). Before moving to the next step, treatment such as heating, electromagnetic wave irradiation, or electron beam irradiation may be performed on the insulating bonding portion 5, or the processing may be moved to the next step as it is. (C) The terminal bonding portion 6 is formed to be thicker than the insulating bonding portion 5 on the circuit 1 by a printing method using a conductive bonding material (A) so that the terminal bonding portion 6 always touches the terminal 4 of the IC bare chip 3. (FIG. 1C). Before moving to the next step, the terminal bonding portion 6 may be subjected to processing such as heating, electromagnetic wave irradiation, or electron beam irradiation, or may be moved to the next step as it is. In any case, volatile components must be removed as much as possible before proceeding to the next step. (D) The IC bare chip 3 is placed by an appropriate method in accordance with the positions of the insulating bonding portion 5 and the terminal bonding portion 6 applied and formed in (b) and (c) above (FIG. 1 (d)). (E) The IC bare chip 3 is crimped B using an appropriate device (FIG. 1 (e)). Desirably, the bonding parts 5 and 6 are set to 0.
This is performed under the condition that the pressure falls within a range of 1 to 0.5 MPa. At this time, the electromagnetic wave irradiation C is simultaneously performed from the back surface of the substrate 2. After the pressure bonding, post-curing by heating or irradiation with electromagnetic waves may be performed to further complete the reaction. Thus, the mounting of the IC bare chip 3 is completed. In addition, in order to protect the mounting portion of the IC bare chip 3, after mounting according to the present invention, the whole or a part of the mounting portion may be covered with a potting material, a coating material, or the like.

The electromagnetic wave used for mounting the IC bare chip may range from microwaves to infrared light, visible light, ultraviolet light, vacuum ultraviolet light, and X-rays, and may have any wavelength within a range of 1 to 10 ^-12 m. Can be used. Using an appropriate resonance frequency with microwaves can selectively cure the adhesive, and the infrared can penetrate through the low-density substrate and heat the adhesive to form the adhesive. The present invention can be applied to both a thermoplastic resin and a thermosetting resin. Further, the visible part, a base that partially transmits ultraviolet light, for example, for a base material such as polyolefin, polyethylene terephthalate, polybutylene terephthalate, polymethacrylate, polycarbonate, and polyether sulfone, the bonded part is illuminated by transmitted light. It can be fixed by crosslinking. Further, electromagnetic waves having higher energy can penetrate through the base material and exert an effect on the adhesive substance to be bonded.

[0014]

As described above, according to the method for mounting an IC bare chip of the present invention, a conductive adhesive substance is printed on a base material on which a circuit is formed in advance at a connection portion with a terminal of the IC bare chip by a printing method. Applying, the terminals are arranged on the base material in correspondence with the application portions of the conductive adhesive material, and when the IC bare chips are pressed on the base material, electromagnetic waves are irradiated from the side opposite to the side on which the IC bare chips are arranged. It is characterized by the following. This eliminates the need to form bumps on the IC bare chip, which has been required for mounting the IC bare chip on the circuit on the base material, and simplifies the process of manufacturing equipment and wiring boards on which the IC bare chip is mounted on the circuit. Can be In addition, the terminal connection between the IC bare chip and the substrate can be formed by the printing method, and each plays a role of connection with the chip, fixing position and relaxing stress, so underfill material is used again There is no need to do it. Further, since the step of forming bumps on the IC bare chip is omitted, the time efficiency of mounting the IC bare chip can be improved. Then, by applying pressure and irradiating electromagnetic waves from the side opposite to the mounting side, it is possible to apply energy to the resin between the IC bare chip and the base material with high efficiency, so that the mounting efficiency is further improved. It has an effect that is excellent in practicality.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a method for mounting an IC bare chip according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Circuit 2 ... Base material 3 ... IC bare chip 4 ... Terminal 5 ... Insulation bonding part 6 ... Terminal bonding part A ... Mounting position B ... Crimping C ... Electromagnetic radiation

Claims (1)

[Claims] 1. A method according to claim 1, wherein a conductive adhesive substance is applied to a connection portion of the IC bare chip with a terminal on a substrate on which a circuit is formed in advance by a printing method, and the terminal is made to correspond to a portion to which the conductive adhesive substance is applied. A method for mounting an IC bare chip, comprising: arranging an IC bare chip on a base material, and irradiating an electromagnetic wave from a side opposite to a side on which the IC bare chip is arranged when the IC bare chip is pressed onto the base material.