WO2020170366A1

WO2020170366A1 - Manufacturing method for semiconductor device, and expand tape

Info

Publication number: WO2020170366A1
Application number: PCT/JP2019/006351
Authority: WO
Inventors: 望松原; 一尊本田; 恵子上野
Original assignee: 日立化成株式会社
Priority date: 2019-02-20
Filing date: 2019-02-20
Publication date: 2020-08-27
Also published as: WO2020171084A1; TW202040657A

Abstract

An expand tape used in a manufacturing method for a semiconductor device, the method comprising: a tape expanding step in which an expand tape is stretched whilst being heated, widening the interval between a plurality of semiconductor chips fixed onto the expand tape from 100µm or less to 300µm or more; an ultraviolet irradiation step in which ultraviolet light is irradiated on the stretched expand tape; and a peeling step in which the expand tape which has been irradiated with ultraviolet light is peeled away from the plurality of semiconductor chips, wherein the peel strength of the expand tape before the ultraviolet irradiation is at least 6N/25mm, and the peel strength after the ultraviolet irradiation is not more than 0.4N/25mm.

Description

Method for manufacturing semiconductor device and expanded tape

The present invention relates to a semiconductor device manufacturing method and an expanded tape.

2. Description of the Related Art In recent years, as semiconductor devices have become smaller, more highly functional, and more highly integrated, the number of pins of semiconductors has increased, the density has increased, and the pitch of wiring has narrowed. Therefore, a fragile layer such as a low-K layer for the purpose of miniaturization of pins or wiring or lowering of the dielectric constant is applied, and along with this, high reliability technology is required.
Against this background, Wafer Level Package (WLP) technology capable of achieving high reliability and high productivity has been developed.
The WLP technique is characterized by assembling the wafer as it is, and dicing the wafer into individual pieces in the final step. This is a technology that enables high productivity and high reliability because it is assembled (sealed) collectively at the wafer level.
In the WLP technology, a rewiring layer in which a rewiring pattern is formed with polyimide, copper wiring, or the like is formed on an insulating film on a circuit surface of a semiconductor chip, and metal pads, solder balls, or the like are mounted on the rewiring to connect them. Configure bumps for terminals.
The WLP includes a semiconductor package such as a WLCSP (Wafer Level Chip Scale Package) or a FI-WLP (Fan In Wafer Level Package) having a package area similar to that of the semiconductor chip, and a FO-WLP (Fan Out Wafer Level Package). There is a semiconductor package in which the package area is larger than the semiconductor chip area and the terminals can be extended to the outside of the chip. Since such semiconductor packages are rapidly becoming smaller and thinner, they are sealed at the wafer level to protect the periphery of the semiconductor chip to ensure reliability, and then the rewiring layer is formed and the package is packaged. Individualization is performed for each.
Reliability is ensured by performing sealing at the wafer level and then performing secondary mounting and the like. Further, also in the field of mounting a single-function semiconductor such as a discrete semiconductor, for the purpose of reducing the stress applied to the cracks or the pad periphery of the semiconductor chip during handling, after sealing the semiconductor chip periphery by performing sealing at the wafer level, Each package is separated into individual pieces and the process is proceeding to the next step (SMT process or the like). Discrete semiconductors are often smaller than the system LCI, and there is a particular demand for 5-sided or 6-sided sealing of the semiconductor chip in order to protect the semiconductor chip to a higher degree.

In order to seal the side surface of the semiconductor chip, it is necessary to divide the wafer into individual pieces to produce semiconductor chips and then widen the intervals between the semiconductor chips. For example, in Patent Document 1, a plurality of chips are fixed on an expand tape, the gap between the semiconductor chips is widened by stretching the expand tape, and then the expand tape is separated from the semiconductor chip, and the method is used. An expandable tape capable of being disclosed is disclosed.

International Publication No. 2018/216621

By the way, at the time of stretching the expand tape, the semiconductor chip fixed on the expand tape comes off, that is, there is a risk of chip jump, and when the expand tape is peeled from the semiconductor chip, the semiconductor chip remains on the expand tape, that is, The transfer rate may decrease. If chip fly occurs or the transfer rate is lowered, there arises a problem that productivity is lowered. The inventors of the present invention have found that there is room for improvement in chip skipping and transfer rate in the expanded tape described in Patent Document 1 when the semiconductor chip is downsized.

Therefore, the present invention is applicable to a method for manufacturing a semiconductor device and a method for manufacturing the same, in which chip skipping and reduction in transfer rate are sufficiently suppressed even when the semiconductor chip is miniaturized (for example, about 1 mm×1 mm). The purpose of the present invention is to provide an expanded tape.

As a result of earnest research, the present inventors have found that the problems described above can be solved by the inventions described in [1] to [8] below.
[1] A tape expanding step of expanding the interval between a plurality of semiconductor chips fixed on the expanded tape from 100 μm or less to 300 μm or more by stretching the expanded tape while heating, and irradiating the stretched expanded tape with ultraviolet rays. An expanded tape used in a method for manufacturing a semiconductor device, which comprises an ultraviolet irradiation step of, and a separation step of separating the expanded tape irradiated with ultraviolet rays from a plurality of semiconductor chips,
An expanded tape having a peel strength of 6 N/25 mm or more before UV irradiation and a peel strength of 0.4 N/25 mm or less after UV irradiation.
[2] The expanded tape according to [1], which has a base material layer and an adhesive layer.
[3] The expanded tape according to [2], wherein the adhesive layer is composed of an ultraviolet curable adhesive.
[4] The adhesive layer comprises an acrylic copolymer having a radiation-curable carbon-carbon double bond-containing group and a hydroxyl group in the main chain, and a crosslinking agent having two or more functional groups capable of reacting with the hydroxyl group. The expand tape according to [2], which contains a photopolymerization initiator and has a crosslinking agent content of 0.05 to 0.3 parts by mass relative to 100 parts by mass of the acrylic copolymer.
[5] The expanded tape according to [4], wherein the crosslinking agent is a crosslinking agent having two or more isocyanate groups.
[6] The expand tape according to [4] or [5], wherein the content of the photopolymerization initiator is 0.5 to 1.5 parts by mass with respect to 100 parts by mass of the acrylic copolymer.
[7] A tape for expanding the interval between a plurality of semiconductor chips fixed on the expanded tape from 100 μm or less to 300 μm or more by stretching the expanded tape according to any one of [1] to [6] while heating. A method of manufacturing a semiconductor device, comprising: an expanding step; an ultraviolet ray irradiating step of irradiating a stretched expanded tape with ultraviolet rays;
[8] A method of manufacturing a semiconductor device having a semiconductor chip, comprising:
A preparatory step of preparing the expanded tape according to any one of [1] to [6] and a plurality of semiconductor chips fixed on the expanded tape;
A tape-expanding step for extending the interval between the plurality of semiconductor chips fixed on the expand tape from 100 μm or less to 300 μm or more by stretching the expand tape;
A tension holding step of holding the tension of the stretched expanded tape,
An ultraviolet irradiation step of irradiating the stretched expanded tape with ultraviolet rays,
A transfer step of transferring a plurality of semiconductor chips to the carrier so that the surface opposite to the surface fixed on the expanded expand tape is fixed.
A peeling step of peeling the expanded tape irradiated with ultraviolet rays from the semiconductor chip,
A method for manufacturing a semiconductor device, comprising:

According to the present invention, a method for manufacturing a semiconductor device and a method for manufacturing the same, in which chip fly and transfer rate decrease are sufficiently suppressed even when the size of the semiconductor chip is reduced (for example, about 1 mm×1 mm) It is an object of the present invention to provide an expanded tape applicable to.

FIG. 9 is a schematic cross-sectional view for explaining the embodiment of the method for manufacturing the semiconductor device. FIG. 9 is a schematic cross-sectional view for explaining the embodiment of the method for manufacturing the semiconductor device. It is a schematic cross section for explaining other embodiment of a manufacturing method of a semiconductor device. It is a schematic cross section for explaining other embodiment of a manufacturing method of a semiconductor device.

Hereinafter, the present embodiment will be described in detail with reference to the drawings. In the following description, the same or corresponding parts will be denoted by the same reference symbols, without redundant description. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

(Method of manufacturing semiconductor device)
The method for manufacturing the semiconductor device of the present embodiment is a tape expand in which a predetermined expand tape to be described later is stretched while being heated to expand the interval between the plurality of semiconductor chips fixed on the expand tape from 100 μm or less to 300 μm or more. A step of irradiating the stretched expanded tape with ultraviolet rays; and a step of peeling the expanded tape irradiated with ultraviolet rays from the plurality of semiconductor chips.
The manufacturing method of the semiconductor device of the present embodiment, a predetermined expand tape described later, and a preparatory step of preparing a plurality of semiconductor chips fixed on the expand tape, by stretching the expand tape, on the expand tape. A tape-expanding step for expanding the distance between a plurality of fixed semiconductor chips from 100 μm or less to 300 μm or more, a tension holding step for holding the tension of the stretched expanded tape, and an ultraviolet irradiation step for irradiating the stretched expanded tape with ultraviolet rays. And a transfer step of transferring a plurality of semiconductor chips to the carrier so that the surface opposite to the surface fixed on the stretched expand tape is fixed, and the expand tape irradiated with ultraviolet rays is applied to the semiconductor chip. It may have a peeling step of peeling from. Each step will be described below.

1 and 2 are schematic cross-sectional views for explaining an embodiment of a method for manufacturing a semiconductor device, and FIGS. 3 and 4 are schematic cross-sectional views for explaining another embodiment of a method for manufacturing a semiconductor device. FIG.

First, in the preparation step, the expanded tape 1 to which a plurality of semiconductor chips 2 are fixed is prepared. The expanded tape 1 has an adhesive layer 1a and a base film 1b, and the adhesive layer 1a contacts the semiconductor chip 2. Further, the semiconductor chip 2 has a circuit surface on which the pads (circuits) 3 are provided. The surface of the semiconductor chip 2 opposite to the circuit surface may be fixed to the expanding tape 1 (FIG. 1A), or the circuit surface may be fixed to the expanding tape 1 (FIG. 3A). ).
In the tape expanding step, the expanding tape 1 is stretched while being heated to increase the distance between the semiconductor chips 2 fixed on the expanding tape 1 (FIG. 1(b) or FIG. 3(b)).
In the tension holding step, the stretched expanded tape 1 is fixed with a fixing jig 4 to hold the tension of the expanded tape 1 (FIG. 1(c) or FIG. 3(c)).
In the ultraviolet irradiation step, the stretched expanded tape 1 is irradiated with ultraviolet rays to reduce the adhesive strength (peel strength) of the expanded tape 1 to the semiconductor chip 2 (FIG. 2A or FIG. 4A).
In the transfer step, the semiconductor chip 2 is transferred onto the carrier 5. In the preparation step, when the surface of the semiconductor chip 2 opposite to the circuit surface is fixed to the expanding tape 1, the circuit surface is fixed to the carrier 5 by the above transfer (FIG. 2B). When the circuit surface of (1) is fixed to the expanding tape 1, the surface opposite to the circuit surface is fixed to the carrier 5 by the transfer (FIG. 4B).
In the peeling step, the expand tape 1 irradiated with ultraviolet rays is peeled from the semiconductor chip 2 (FIG. 2(c) or FIG. 4(c)).
Hereinafter, each step will be described in detail.

<Preparation process>
The method for preparing the expand tape and the plurality of semiconductor chips fixed on the expand tape is not particularly limited. For example, it can be manufactured by laminating a semiconductor wafer on a dicing tape or the like, dicing it with a blade or a laser to obtain a plurality of individual semiconductor chips, and then transferring these to an expanding tape.
The dicing may be performed by forming a brittle layer with a laser and expanding. Further, from the viewpoint of omitting the above-mentioned transfer and improving the productivity, the semiconductor wafer may be directly laminated on the expand tape and the semiconductor wafer may be diced by the above-mentioned method.

From the viewpoint of productivity improvement and cost reduction, the initial semiconductor chip interval (semiconductor chip interval before the tape expanding step) is preferably narrow, and is 100 μm or less, preferably 80 μm or less, and more preferably 60 μm or less. In the cutting of the wear by dicing, the semiconductor wafer is wasted as the chip interval is wider, and thus the narrower one is preferable from the viewpoint of cost reduction. In order to prevent stress from being applied to the semiconductor chips when the chip intervals are widened, the initial intervals between the semiconductor chips are preferably 10 μm or more. If it is smaller than 10 μm, the expanded tape region between a plurality of semiconductor chips is small and it is difficult to spread.

The type of pad on the circuit surface of the semiconductor chip is not particularly limited as long as it can be formed on the circuit surface of the semiconductor chip, and even if bumps (projection electrodes) such as copper bumps and solder bumps are used, Ni/Au It may be a relatively flat metal pad such as a plating pad.

<Tape expanding process>
By stretching the expanded tape, the intervals between the plurality of semiconductor chips are widened.

Extending tape stretching methods include, for example, a push-up method and a pulling method. In the push-up method, the expand tape is stretched by fixing the expand tape and then raising the stage having a predetermined shape. The pulling method is a method in which the expand tape is stretched by fixing the expand tape and then pulling it in a predetermined direction in parallel with the surface of the installed expand tape. The push-up method is preferable because the distance between the semiconductor chips can be uniformly extended and the required (occupied) device area is small and compact.

The stretching conditions may be appropriately set according to the characteristics of the expanded tape. For example, when the push-up method is adopted, the push-up amount (pull amount) is preferably 10 to 150 mm, more preferably 10 to 120 mm. When it is 10 mm or more, the intervals between the plurality of semiconductor chips are easily widened, and when it is 150 mm or less, the scattering or displacement of the semiconductor chips can be more highly prevented.
The temperature at the time of stretching may be appropriately set according to the characteristics of the expanded tape, but may be, for example, 10 to 200°C, 10 to 150°C, or 20 to 100°C. When the temperature is 10° C. or higher, the expand tape is easily stretched, and when the temperature is 200° C. or lower, the semiconductor tape is displaced due to distortion or slack due to thermal expansion or low elasticity of the expand tape (between the expand tape and the semiconductor chip. Peeling) and scattering of semiconductor chips can be prevented to a higher degree.
The push-up speed may be appropriately set according to the characteristics of the expanded tape, but may be, for example, 0.1 to 500 mm/sec, 0.1 to 300 mm/sec, or 0.1 to 200 mm/sec. .. When it is 0.1 mm/sec or more, productivity is improved. When it is 500 mm/sec or less, peeling between the semiconductor chip and the expanding tape becomes difficult to occur.

After the tape expanding process, the interval between the plurality of semiconductor chips is preferably 500 μm or more in order to secure the space required for providing the rewiring pattern and the connection terminal pads outside the semiconductor chip area. Since the total number of rewiring layers is increased in a semiconductor package having a high density and high functionality, it is necessary to provide a connection terminal pad outside the semiconductor chip. Therefore, it is preferable that the semiconductor chip interval be wide. From the above viewpoint, the interval between the plurality of semiconductor chips after the tape expanding step is more preferably 1 mm or more, further preferably 2 mm or more. The upper limit is not particularly limited, but can be 5 mm or less.

The distance between the semiconductor chips after the tape expanding step may be 300 μm or more, but an appropriate distance can be selected according to the application.
In the FO-WLP application, 500 μm or more is preferable in order to secure a space necessary for providing the rewiring pattern and the connection terminal pad outside the region of the semiconductor chip. Since the total number of rewiring layers increases in a high-density and high-performance semiconductor package, it is necessary to provide a connection terminal pad on the outer side of the semiconductor chip. Therefore, it is preferable that the semiconductor chip interval be wide. From the above viewpoint, the interval between the plurality of semiconductor chips after the tape expanding step is preferably 1 mm or more, more preferably 2 mm or more.
In addition, in the FI-WLP application or the discrete semiconductor chip mounting application, the distance between the semiconductor chips after the tape expanding step is 300 μm or more from the viewpoint of surely protecting the side surface of the semiconductor chip with a sealing material. From the viewpoint of handleability, the interval between the plurality of semiconductor chips after the tape expanding step is preferably 500 μm or more, and more preferably 1 mm.
The upper limit of the distance between the semiconductor chips after the tape expanding step is not particularly limited, but can be 5 mm or less.

<Tension holding process>
The tension of the expanded tape is maintained to prevent the stretched expanded tape from returning to its original state.

There is no particular limitation on the method of maintaining the tension of the expand tape as long as the tension is maintained and the distance between the semiconductor chips is not restored. For example, a method of fixing using a fixing jig such as a grip ring (manufactured by Technovision Co., Ltd.), a method of heating the outer peripheral portion of the expanded tape to shrink it (heat shrink) and maintaining tension can be mentioned.

<Ultraviolet irradiation process>
By irradiating the stretched expanded tape with ultraviolet rays, the adhesive strength of the expanded tape to the semiconductor chip is reduced. In the present embodiment, it is preferable to use ultraviolet rays having a wavelength of 200 to 400 nm, and it is preferable that the irradiation conditions are such that the illuminance is 30 to 240 mW/cm ² and the irradiation amount is 200 to 500 mJ/cm ^2. ..

<Transfer process>
Transfer (laminate) is performed so that the semiconductor chip is fixed to the carrier. The laminating method is not particularly limited, but a roll laminator, a diaphragm laminator, a vacuum roll laminator, or a vacuum diaphragm laminator can be used.

Lamination conditions may be set appropriately according to the physical properties and characteristics of the expanded tape, semiconductor chip and carrier. For example, in the case of a roll laminator, the temperature may be room temperature (25°C) to 200°C, preferably room temperature (25°C) to 150°C, and more preferably room temperature (25°C) to 100°C. When the temperature is room temperature or higher, the semiconductor chip is easily transferred (laminated) to the carrier, and when the temperature is 200° C. or lower, the semiconductor tape is misaligned due to strain or slack due to thermal expansion or low elasticity of the expand tape (expand tape and semiconductor chip). It is possible to more highly prevent the separation of the semiconductor chip) and the scattering of the semiconductor chip. If it is a diaphragm type laminator, the temperature condition is the same as that of the roll laminator described above. The pressure bonding time may be 5 to 300 seconds, preferably 5 to 200 seconds, more preferably 5 to 100 seconds. When it is 5 seconds or more, the semiconductor chip is easily transferred (laminated) to the carrier, and when it is 300 seconds or less, the productivity is improved. The pressure may be 0.1 to 3 MPa, preferably 0.1 to 2 MPa, more preferably 0.1 to 1 MPa. When it is 0.1 MPa or more, the semiconductor chip is easily transferred (laminated) to the carrier, and when it is 3 MPa or less, damage to the semiconductor chip is reduced.

<Peeling process>
The expand tape irradiated with ultraviolet rays is peeled (removed) from the plurality of semiconductor chips.

According to the method for manufacturing a semiconductor device of the present embodiment, in the ultraviolet irradiation step prior to the peeling step, since the adhesive strength of the expand tape to the semiconductor chip is reduced, stress on the semiconductor chip during peeling is reduced. The peeling can be performed smoothly without displacement.

In addition to the above steps, the method for manufacturing a semiconductor device of the present embodiment further includes a sealing step of sealing a plurality of semiconductor chips on a carrier with a sealing material, and a plurality of semiconductor chips sealed with a sealing material. At least one of a second peeling step of peeling the carrier from the semiconductor chip and a semiconductor package forming step of forming a plurality of semiconductor packages by dividing a plurality of semiconductor chips sealed by a sealing material into individual semiconductor chips May be. These steps can be carried out with reference to Patent Document 1 described above.

Next, the materials used in each process will be explained.

(Expanding tape)
The expanded tape of the present embodiment is an expanded tape used in the above-described method for manufacturing a semiconductor device, which has a peel strength before UV irradiation of 6 N/25 mm or more and a peel strength after UV irradiation of 0.4 N/ It is 25 mm or less. The peel strength referred to here is the peel strength of the expanded tape with respect to SUS when a stainless steel material (SUS) is attached to the expanded tape. Specifically, for example, the peel strength measured after applying an expanding tape at a lamination temperature of 40° C. to a SUS having a thickness of 0.5 mm by using Laminator GK-13DX (manufactured by Lamy Corporation) is UV. It is the peel strength before irradiation and after the expanded tape is irradiated with ultraviolet rays under the conditions of ultraviolet wavelength: 365 nm and exposure amount: 300 mJ/cm ² using an ultraviolet exposure device (“ML-320FSAT” manufactured by Mikasa Co., Ltd.) The peel strength measured is the peel strength after irradiation with ultraviolet rays. The peel strength can be evaluated in accordance with JIS C 5016 (1994-Peeling strength of conductor).

The peel strength of the expanded tape before ultraviolet irradiation is preferably 7 N/25 mm or more, and 8 N/25 mm or more from the viewpoint that the semiconductor chip can be more highly prevented from scattering or misalignment in the tape expanding step. Is more preferable and 9 N/25 mm or more is further preferable. The upper limit of the peel strength of the expanded tape before ultraviolet irradiation is not particularly limited, but may be, for example, 15 N/25 mm or less.

The peel strength of the expanded tape after irradiation with ultraviolet rays is preferably 0.35 N/25 mm or less from the viewpoint of further improving the transfer rate of the semiconductor chip in the transfer step. The lower limit of the peel strength of the expanded tape after irradiation with ultraviolet rays is not particularly limited, but may be 0.1 N/25 mm or more, for example.

The expanded tape may have a multi-layer structure such as a base film (base layer) that greatly contributes to the stretchability and an adhesive layer that controls the adhesive strength.

(Base film)
The substrate film is not particularly limited as long as it has stretchability and stability that holds the semiconductor chip interval after the tension holding step.

The base material film is a polyester film such as polyethylene terephthalate film; polytetrafluoroethylene film, polyethylene film, polypropylene film, polymethylpentene film, polyvinyl acetate film, and α-olefin such as poly-4-methylpentene-1. It may be various plastic films such as a homopolymer and a copolymer thereof, and a polyolefin film containing the homopolymer or the ionomer of the above copolymer; a polyvinyl chloride film; and a polyimide film; a urethane resin film. The base film is not limited to a single-layer film, and may be a multi-layer film obtained by combining two or more kinds of the plastic films or two or more plastic films of the same kind.

The above base film is preferably a polyolefin film or a urethane resin film from the viewpoint of stretchability. The base film may contain various additives such as an antiblocking agent, if necessary.

The thickness of the base film may be appropriately set if necessary, but is preferably 50 to 500 μm. If it is thinner than 50 μm, the stretchability is deteriorated, and if it is thicker than 500 μm, distortions are likely to occur and handling properties are deteriorated.

The thickness of the base film is appropriately selected within a range that does not impair workability. However, when a high-energy ray (in particular, ultraviolet ray) curable adhesive is used as the adhesive constituting the adhesive layer, it is necessary to have a thickness that does not hinder the transmission of the high-energy ray. From such a viewpoint, the thickness of the base film may be usually 10 to 500 μm, preferably 50 to 400 μm, and more preferably 70 to 300 μm.
When the base material layer is composed of a plurality of base material films, it is preferable to adjust the total thickness of the base material layer within the above range. The base film may be chemically or physically surface-treated, if necessary, in order to improve the adhesion with the adhesive layer. Examples of the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, and ionizing radiation treatment.

(Adhesive layer)
The adhesive layer preferably contains an acrylic copolymer (acrylic resin), a crosslinking agent, and a photopolymerization initiator. Hereinafter, these components will be described. The content of the acrylic copolymer in the adhesive layer is preferably more than 50 parts by mass with respect to 100 parts by mass of the composition constituting the adhesive layer.

The above acrylic copolymer has at least a radiation-curable carbon-carbon double bond-containing group and a hydroxyl group in the main chain.

The acrylic resin or methacrylic resin (hereinafter referred to as “(meth)acrylic resin”) as the acrylic copolymer may be a resin having an unsaturated bond in its side chain and having adhesiveness itself. There is no limit. Specifically, the glass transition temperature is −40° C. or lower, the hydroxyl value is 20 to 150 mgKOH/g, the chain-polymerizable functional group is 0.3 to 1.5 mmol/g, and the acid value is Examples thereof include resins that are not substantially detected and have a weight average molecular weight of 300,000 or more.

The (meth)acrylic resin having such characteristics can be obtained by synthesizing by a known method, and for example, a solution polymerization method, a suspension polymerization method, an emulsion polymerization method, a bulk polymerization method, a precipitation polymerization method. , A gas phase polymerization method, a plasma polymerization method, a supercritical polymerization method and the like are used. As the type of the polymerization reaction, radical polymerization, cationic polymerization, anionic polymerization, living radical polymerization, living cationic polymerization, living anionic polymerization, coordination polymerization, immodal polymerization and the like, and methods such as ATRP or RAFT can also be used. Among these, synthesis by radical polymerization using a solution polymerization method can be compounded using the resin solution obtained by polymerization as it is, in addition to good economic efficiency, high reaction rate, easy control of polymerization, and the like. It is preferable because it is easy to mix.

Here, a method of obtaining a (meth)acrylic resin by radical polymerization using a solution polymerization method will be described in detail as an example.

The monomer used when synthesizing the (meth)acrylic resin is not particularly limited as long as it has one (meth)acryloyl group in one molecule, but if specifically exemplified, Methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, butoxyethyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate , 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, octylheptyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth) Acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, methoxy polyethylene glycol (meth)acrylate, ethoxy polyethylene glycol (meth)acrylate, methoxy polypropylene Aliphatic (meth)acrylates such as glycol (meth)acrylate, ethoxy polypropylene glycol (meth)acrylate, mono(2-(meth)acryloyloxyethyl)succinate; cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentyl ( (Meth)acrylate, dicyclopentanyl(meth)acrylate, dicyclopentenyl(meth)acrylate, isobornyl(meth)acrylate, mono(2-(meth)acryloyloxyethyl)tetrahydrophthalate, mono(2-(meth)acryl Alicyclic (meth)acrylates such as royroxyethyl)hexahydrophthalate; benzyl (meth)acrylate, phenyl (meth)acrylate, o-biphenyl (meth)acrylate, 1-naphthyl (meth)acrylate, 2-naphthyl (meth ) Acrylate, phenoxyethyl (meth)acrylate, p-cumylphenoxyethyl (meth)acrylate, o-phenylphenoxyethyl (meth)acrylate, 1-naphthoxyethyl (meth)acrylate, 2-naphthoxyethyl (meth)acrylate, phenoxypolyethylene glycol (Meth)acrylate, nonylphenoxy polyethylene glycol (Meth)acrylate, phenoxy polypropylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-hydroxy-3-(o-phenylphenoxy)propyl (meth)acrylate, 2-hydroxy-3 Aromatic (meth)acrylates such as -(1-naphthoxy)propyl(meth)acrylate and 2-hydroxy-3-(2-naphthoxy)propyl(meth)acrylate; 2-tetrahydrofurfuryl(meth)acrylate, N-( Heterocyclic (meth)acrylates such as (meth)acryloyloxyethyl hexahydrophthalimide, 2-(meth)acryloyloxyethyl-N-carbazole, caprolactone modified products thereof, ω-carboxy-polycaprolactone mono(meth)acrylate , Glycidyl (meth)acrylate, α-ethylglycidyl (meth)acrylate, α-propylglycidyl (meth)acrylate, α-butylglycidyl (meth)acrylate, 2-methylglycidyl (meth)acrylate, 2-ethylglycidyl (meth) Acrylate, 2-propylglycidyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, 3,4-epoxyheptyl (meth)acrylate, α-ethyl-6,7-epoxyheptyl (meth)acrylate, 3, Compounds having an ethylenically unsaturated group and an epoxy group such as 4-epoxycyclohexylmethyl (meth)acrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether and p-vinylbenzyl glycidyl ether; (2-ethyl-2 -Oxetanyl)methyl(meth)acrylate, (2-methyl-2-oxetanyl)methyl(meth)acrylate, 2-(2-ethyl-2-oxetanyl)ethyl(meth)acrylate, 2-(2-methyl-2- Oxetanyl with ethylenically unsaturated groups such as oxetanyl)ethyl(meth)acrylate, 3-(2-ethyl-2-oxetanyl)propyl(meth)acrylate, 3-(2-methyl-2-oxetanyl)propyl(meth)acrylate Compounds having a group; compounds having an ethylenically unsaturated group such as 2-(meth)acryloyloxyethyl isocyanate and an isocyanate group; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (Meth)acrylate, 3-chloro- Examples thereof include compounds having an ethylenically unsaturated group and a hydroxyl group such as 2-hydroxypropyl (meth)acrylate and 2-hydroxybutyl (meth)acrylate, and the desired composition can be obtained by appropriately combining these.

Further, if necessary, styrene, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-isobutylmaleimide, N-2-methyl, which can be copolymerized with the above-mentioned monomers. -2-propylmaleimide, N-pentylmaleimide, N-2-pentylmaleimide, N-3-pentylmaleimide, N-2-methyl-1-butylmaleimide, N-2-methyl-2-butylmaleimide, N-3 -Methyl-1-butylmaleimide, N-3-methyl-2-butylmaleimide, N-hexylmaleimide, N-2-hexylmaleimide, N-3-hexylmaleimide, N-2-methyl-1-pentylmaleimide, N -2-Methyl-2-pentylmaleimide, N-2-methyl-3-pentylmaleimide, N-3-methyl-1-pentylmaleimide, N-3-methyl-2-pentylmaleimide, N-3-methyl-3 -Pentyl maleimide, N-4-methyl-1-pentyl maleimide, N-4-methyl-2-pentyl maleimide, N-2,2-dimethyl-1-butyl maleimide, N-3,3-dimethyl-1-butyl Maleimide, N-3,3-dimethyl-2-butylmaleimide, N-2,3-dimethyl-1-butylmaleimide, N-2,3-dimethyl-2-butylmaleimide, N-hydroxymethylmaleimide, N-1 -Hydroxyethylmaleimide, N-2-hydroxyethylmaleimide, N-1-hydroxy-1-propylmaleimide, N-2-hydroxy-1-propylmaleimide, N-3-hydroxy-1-propylmaleimide, N-1- Hydroxy-2-propylmaleimide, N-2-hydroxy-2-propylmaleimide, N-1-hydroxy-1-butylmaleimide, N-2-hydroxy-1-butylmaleimide, N-3-hydroxy-1-butylmaleimide , N-4-hydroxy-1-butylmaleimide, N-1-hydroxy-2-butylmaleimide, N-2-hydroxy-2-butylmaleimide, N-3-hydroxy-2-butylmaleimide, N-4-hydroxy -2-Butylmaleimide, N-2-Methyl-3-hydroxy-1-propylmaleimide, N-2-Methyl-3-hydroxy-2-propylmaleimide, N-2-Methyl-2-hydroxy-1-propylmaleimide , N-1-hydroxy-1-pentylmaleimide, N-2-hydroxy-1-pentylmaleimide Imido, N-3-hydroxy-1-pentylmaleimide, N-4-hydroxy-1-pentylmaleimide, N-5-hydroxy-1-pentylmaleimide, N-1-hydroxy-2-pentylmaleimide, N-2- Hydroxy-2-pentylmaleimide, N-3-hydroxy-2-pentylmaleimide, N-4-hydroxy-2-pentylmaleimide, N-5-hydroxy-2-pentylmaleimide, N-1-hydroxy-3-pentylmaleimide , N-2-hydroxy-3-pentylmaleimide, N-3-hydroxy-3-pentylmaleimide, N-1-hydroxy-2-methyl-1-butylmaleimide, N-1-hydroxy-2-methyl-2- Butyl maleimide, N-1-hydroxy-2-methyl-3-butyl maleimide, N-1-hydroxy-2-methyl-4-butyl maleimide, N-2-hydroxy-2-methyl-1-butyl maleimide, N- 2-hydroxy-2-methyl-3-butylmaleimide, N-2-hydroxy-2-methyl-4-butylmaleimide, N-2-hydroxy-3-methyl-1-butylmaleimide, N-2-hydroxy-3 -Methyl-2-butylmaleimide, N-2-hydroxy-3-methyl-3-butylmaleimide, N-2-hydroxy-3-methyl-4-butylmaleimide, N-4-hydroxy-2-methyl-1- Butyl maleimide, N-4-hydroxy-2-methyl-2-butyl maleimide, N-1-hydroxy-3-methyl-2-butyl maleimide, N-1-hydroxy-3-methyl-1-butyl maleimide, N- 1-hydroxy-2,2-dimethyl-1-propylmaleimide, N-3-hydroxy-2,2-dimethyl-1-propylmaleimide, N-1-hydroxy-1-hexylmaleimide, N-1-hydroxy-2 -Hexylmaleimide, N-1-hydroxy-3-hexylmaleimide, N-1-hydroxy-4-hexylmaleimide, N-1-hydroxy-5-hexylmaleimide, N-1-hydroxy-6-hexylmaleimide, N- 2-hydroxy-1-hexylmaleimide, N-2-hydroxy-2-hexylmaleimide, N-2-hydroxy-3-hexylmaleimide, N-2-hydroxy-4-hexylmaleimide, N-2-hydroxy-5- Hexylmaleimide, N-2-hydroxy-6-hexylmaleimide, N-3-hydroxy-1-hexylmaleimide, N -3-Hydroxy-2-hexylmaleimide, N-3-Hydroxy-3-hexylmaleimide, N-3-Hydroxy-4-hexylmaleimide, N-3-Hydroxy-5-hexylmaleimide, N-3-Hydroxy-6 -Hexylmaleimide, N-1-hydroxy-2-methyl-1-pentylmaleimide, N-1-hydroxy-2-methyl-2-pentylmaleimide, N-1-hydroxy-2-methyl-3-pentylmaleimide, N -1-hydroxy-2-methyl-4-pentylmaleimide, N-1-hydroxy-2-methyl-5-pentylmaleimide, N-2-hydroxy-2-methyl-1-pentylmaleimide, N-2-hydroxy- 2-methyl-2-pentylmaleimide, N-2-hydroxy-2-methyl-3-pentylmaleimide, N-2-hydroxy-2-methyl-4-pentylmaleimide, N-2-hydroxy-2-methyl-5 -Pentylmaleimide, N-2-hydroxy-3-methyl-1-pentylmaleimide, N-2-hydroxy-3-methyl-2-pentylmaleimide, N-2-hydroxy-3-methyl-3-pentylmaleimide, N -2-hydroxy-3-methyl-4-pentylmaleimide, N-2-hydroxy-3-methyl-5-pentylmaleimide, N-2-hydroxy-4-methyl-1-pentylmaleimide, N-2-hydroxy- 4-methyl-2-pentylmaleimide, N-2-hydroxy-4-methyl-3-pentylmaleimide, N-2-hydroxy-4-methyl-4-pentylmaleimide, N-2-hydroxy-4-methyl-5 -Pentylmaleimide, N-3-Hydroxy-2-methyl-1-pentylmaleimide, N-3-Hydroxy-2-methyl-2-pentylmaleimide, N-3-Hydroxy-2-methyl-3-pentylmaleimide, N -3-hydroxy-2-methyl-4-pentylmaleimide, N-3-hydroxy-2-methyl-5-pentylmaleimide, N-1-hydroxy-4-methyl-1-pentylmaleimide, N-1-hydroxy- 4-methyl-2-pentylmaleimide, N-1-hydroxy-4-methyl-3-pentylmaleimide, N-1-hydroxy-4-methyl, N-1-hydroxy-3-methyl-1-pentylmaleimide, N -1-hydroxy-3-methyl-2-pentylmaleimide, N-1-hydroxy-3-methyl-3-pentylmaleimide, N-1-hydro Xy-3-methyl-4-pentylmaleimide, N-1-hydroxy-3-methyl-5-pentylmaleimide, N-3-hydroxy-3-methyl-1-pentylmaleimide, N-3-hydroxy-3-methyl -2-Pentylmaleimide, N-1-hydroxy-3-ethyl-4-butylmaleimide, N-2-hydroxy-3-ethyl-4-butylmaleimide, N-2-hydroxy-2-ethyl-1-butylmaleimide , N-4-hydroxy-3-ethyl-1-butylmaleimide, N-4-hydroxy-3-ethyl-2-butylmaleimide, N-4-hydroxy-3-ethyl-3-butylmaleimide, N-4- Hydroxy-3-ethyl-4-butylmaleimide, N-1-hydroxy-2,3-dimethyl-1-butylmaleimide, N-1-hydroxy-2,3-dimethyl-2-butylmaleimide, N-1-hydroxy -2,3-Dimethyl-3-butylmaleimide, N-1-hydroxy-2,3-dimethyl-4-butylmaleimide, N-2-hydroxy-2,3-dimethyl-1-butylmaleimide, N-2- Hydroxy-2,3-dimethyl-3-butylmaleimide, N-2-hydroxy-2,3-dimethyl-4-butylmaleimide, N-1-hydroxy-2,2-dimethyl-1-butylmaleimide, N-1 -Hydroxy-2,2-dimethyl-3-butylmaleimide, N-1-hydroxy-2,2-dimethyl-4-butylmaleimide, N-2-hydroxy-3,3-dimethyl-1-butylmaleimide, N- 2-hydroxy-3,3-dimethyl-2-butylmaleimide, N-2-hydroxy-3,3-dimethyl-4-butylmaleimide, N-1-hydroxy-3,3-dimethyl-1-butylmaleimide, N Alkyl maleimides such as 1-hydroxy-3,3-dimethyl-2-butylmaleimide and N-1-hydroxy-3,3-dimethyl-4-butylmaleimide; N-cyclopropylmaleimide, N-cyclobutylmaleimide, N Cycloalkylmaleimides such as cyclopentylmaleimide, N-cyclohexylmaleimide, N-cycloheptylmaleimide, N-cyclooctylmaleimide, N-2-methylcyclohexylmaleimide, N-2-ethylcyclohexylmaleimide, N-2-chlorocyclohexylmaleimide; N-phenylmaleimide, N-2-methylphenylmaleimide, N-2-ethylphenylmaleimide, N-2-chloro An aryl maleimide such as rophenyl maleimide can be used as appropriate.

Among these, it is preferable to use at least one selected from (meth)acrylic esters, which are C8 to C23 aliphatic esters. The (meth)acrylic resin obtained by copolymerizing such a monomer component has a low glass transition temperature and thus exhibits excellent adhesive properties, which is preferable.

Further, the polymerization initiator necessary for obtaining such a (meth)acrylic resin is not particularly limited as long as it is a compound that generates a radical by heating at 30° C. or higher, and examples thereof include methyl ethyl ketone peroxide and cyclohexanone peroxide. Ketone ketones such as methylcyclohexanone peroxide; 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)-2-methylcyclohexane, 1,1-bis(t -Butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane Peroxyketals such as; hydroperoxides such as p-menthane hydroperoxide; α,α′-bis(t-butylperoxy)diisopropylbenzene, dicumyl peroxide, t-butylcumyl peroxide, di-t- Dialkyl peroxides such as butyl peroxide; diacyl peroxides such as octanoyl peroxide, lauroyl peroxide, stearyl peroxide, benzoyl peroxide; bis(4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxy Peroxycarbonates such as ethylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate and di-3-methoxybutylperoxycarbonate; t-butylperoxypivalate, t-hexylperoxypivalate, 1,1 ,3,3-Tetramethylbutylperoxy-2-ethylhexanoate, 2,5-Dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, t-hexylperoxy-2-ethylhexa Noate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate , T-butylperoxylaurylate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-butylperoxybenzoate, t-hexylperoxybenzoate, 2,5-dimethyl- Peroxyesters such as 2,5-bis(benzoylperoxy)hexane and t-butylperoxyacetate; 2,2′-azobi Examples thereof include suisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile) and 2,2'-azobis(4-methoxy-2'-dimethylvaleronitrile).

The reaction solvent used in the solution polymerization is not particularly limited as long as it can dissolve the (meth)acrylic resin, and examples thereof include aromas such as toluene, xylene, mesitylene, cumene and p-cymene. Group hydrocarbons; cyclic ethers such as tetrahydrofuran and 1,4-dioxane; alcohols such as methanol, ethanol, isopropanol, butanol, ethylene glycol, propylene glycol; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl -Ketones such as 2-pentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone; carbonic acid esters such as ethylene carbonate and propylene carbonate; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether , Ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether , Polyhydric alcohol alkyl ethers such as diethylene glycol diethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol Examples include polyhydric alcohol alkyl ether acetates such as monoethyl ether acetate; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone. These organic solvents may be used alone or Combinations of more than one type can be used. Further, supercritical carbon dioxide can be used as a solvent for polymerization.

Photosensitivity can be imparted by chemically bonding to (meth)acrylic resin a functional group capable of reacting with irradiation of ultraviolet rays, electron beams, and/or visible rays. As used herein, the functional group capable of reacting with irradiation of ultraviolet rays, electron beams, and/or visible rays is, if specifically exemplified, a (meth)acryloyl group, a vinyl group, an allyl group, a glycidyl group, or a fat. Examples thereof include a cyclic epoxy group and an oxetane group.

The method for imparting photosensitivity to the (meth)acrylic resin is not particularly limited, but, for example, when synthesizing the above (meth)acrylic resin, a functional group capable of undergoing an addition reaction in advance, for example, a hydroxyl group or a carboxyl group. , A maleic anhydride group, a glycidyl group, an amino group and the like are copolymerized to introduce a functional group capable of undergoing an addition reaction into a (meth)acrylic resin, and at least one ethylenically unsaturated group and epoxy Group, an oxetanyl group, an isocyanate group, a hydroxyl group, a carboxyl group and the like, and a compound having at least one functional group is added to react to introduce an ethylenically unsaturated group into a side chain, thereby producing a (meth)acrylic resin. Can be imparted with photosensitivity.

There is no particular limitation on such a compound, and glycidyl (meth)acrylate, α-ethylglycidyl (meth)acrylate, α-propylglycidyl (meth)acrylate, α-butylglycidyl (meth)acrylate, 2-methylglycidyl (meth) ) Acrylate, 2-ethylglycidyl (meth)acrylate, 2-propylglycidyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, 3,4-epoxyheptyl (meth)acrylate, α-ethyl-6,7 -Epoxy heptyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether and other ethylenically unsaturated groups and epoxy groups A compound having: (2-ethyl-2-oxetanyl)methyl(meth)acrylate, (2-methyl-2-oxetanyl)methyl(meth)acrylate, 2-(2-ethyl-2-oxetanyl)ethyl(meth)acrylate , 2-(2-methyl-2-oxetanyl)ethyl(meth)acrylate, 3-(2-ethyl-2-oxetanyl)propyl(meth)acrylate, 3-(2-methyl-2-oxetanyl)propyl(meth) Compounds having an ethylenically unsaturated group such as acrylate and an oxetanyl group; methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, 2-acryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate and other ethylenically unsaturated compounds Group having a hydroxyl group and an isocyanate group; ethylene such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate and 2-hydroxybutyl (meth)acrylate Compounds having a polyunsaturated group and a hydroxyl group; (meth)acrylic acid, crotonic acid, cinnamic acid, succinic acid (2-(meth)acryloyloxyethyl), 2-phthaloylethyl (meth)acrylate, 2- Ethylenic unsaturation of tetrahydrophthaloylethyl (meth)acrylate, 2-hexahydrophthaloylethyl (meth)acrylate, ω-carboxy-polycaprolactone mono(meth)acrylate, 3-vinylbenzoic acid, 4-vinylbenzoic acid, etc. Examples include compounds having a group and a carboxyl group To be

Among these, from the viewpoint of cost and/or reactivity, 2-(meth)acryloyloxyethyl isocyanate, glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, ethyl isocyanate (meth)acrylate, 2 -Using hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, (meth)acrylic acid, crotonic acid, 2-hexahydrophthaloylethyl (meth)acrylate , (Meth)acrylic resin is preferably reacted to impart photosensitivity. These compounds can be used alone or in combination of two or more kinds. If necessary, a catalyst that accelerates the addition reaction or a polymerization inhibitor may be added for the purpose of avoiding double bond cleavage during the reaction. More preferably, it is a reaction product of an (meth)acrylic resin containing an OH group and at least one selected from 2-methacryloyloxyethyl isocyanate and 2-acryloyloxyethyl isocyanate.

The cross-linking agent is a compound having at least one selected from a hydroxyl group, a glycidyl group, an amino group, and the like introduced into a (meth)acrylic resin, and two or more functional groups capable of reacting with these functional groups, There is no limit to its structure. Examples of the bond formed by such a crosslinking agent include an ester bond, an ether bond, an amide bond, an imide bond, a urethane bond and a urea bond.

The amount of the crosslinking agent contained in the adhesive layer is preferably 0.05 to 0.3 parts by mass with respect to 100 parts by mass of the acrylic copolymer. If the amount of the cross-linking agent is less than 0.05 parts by mass, it may cause the adhesive layer to become brittle after irradiation with ultraviolet rays. On the other hand, when the amount of the cross-linking agent exceeds 0.3 parts by mass, the adhesive force of the adhesive layer before the irradiation of ultraviolet rays tends to be weak, and the force for fixing the semiconductor chip tends to be insufficient.

As the cross-linking agent, one having two or more isocyanate groups is preferable. When such a compound is used, it easily reacts with the hydroxyl group, glycidyl group, amino group, etc. introduced into the (meth)acrylic resin to form a strong cross-linked structure, and the adhesive layer becomes brittle after irradiation with ultraviolet rays. Can be suppressed.

Here, the cross-linking agent having two or more isocyanate groups is, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4. -Xylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2, Isocyanate compounds such as 4'-diisocyanate and lysine isocyanate are mentioned.

Furthermore, an isocyanate group-containing oligomer obtained by reacting the above-mentioned isocyanate compound with a polyhydric alcohol having two or more OH groups can also be used. When obtaining such an oligomer, examples of the polyhydric alcohol having two or more OH groups include ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, and 1,9. -Nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, glycerin, pentaerythritol, dipentaerythritol, 1,4-cyclohexanediol, 1,3-cyclohexanediol and the like. To be

Among these, it is more preferable that the cross-linking agent is a reaction product of a polyfunctional isocyanate having two or more isocyanate groups and a polyhydric alcohol having three or more OH groups. By using such an isocyanate group-containing oligomer, it is possible to prevent the pressure-sensitive adhesive layer from forming a dense cross-linked structure and making the pressure-sensitive adhesive layer brittle after irradiation with ultraviolet rays.

The photopolymerization initiator is not particularly limited as long as it generates an active species capable of causing chain polymerization of the acrylic copolymer by irradiation with one or more kinds of light selected from ultraviolet rays, electron rays and visible rays. However, for example, it may be a photoradical polymerization initiator or a photocationic polymerization initiator. The chain-polymerizable active species is not particularly limited as long as it can initiate a polymerization reaction by reacting with the functional group of the acrylic copolymer.

Examples of the photoradical polymerization initiator include benzoin ketals such as 2,2-dimethoxy-1,2-diphenylethan-1-one; 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane- Α-Hydroxyketone such as 1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one; 2-benzyl-2-dimethylamino-1 Α-aminoketone such as -(4-morpholinophenyl)-butan-1-one and 1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one; 1-[ (4-phenylthio)phenyl]-1,2-octadion-2-(benzoyl)oxime and other oxime esters; bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)- Phosphine oxides such as 2,4,4-trimethylpentylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o- Chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenyl 2,4,5-triarylimidazole dimers such as imidazole dimers and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimers; benzophenone, N,N,N',N-tetra Benzophenone compounds such as methyl-4,4'-diaminobenzophenone, N,N,N',N-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone; 2-ethylanthraquinone, phenanthrene Quinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1 , 4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone and other quinone compounds; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether Benzoin ethers such as; benzoin compounds such as benzoin, methylbenzoin, ethylbenzoin; benzyl compounds such as benzyldimethylketal; acridine compounds such as 9-phenylacridine, 1,7-bis(9,9'-acridinylheptane) Examples thereof include N-phenylglycine and coumarin.

Further, in the above-mentioned 2,4,5-triarylimidazole dimer, the substituents on the aryl groups of the two triarylimidazole moieties may give the same and symmetrical compounds, and different asymmetrical compounds are given. May be given. Also. A thioxanthone compound and a tertiary amine may be combined, such as a combination of diethylthioxanthone and dimethylaminobenzoic acid.

Examples of the cationic photopolymerization initiator include aryldiazonium salts such as p-methoxybenzenediazonium hexafluorophosphate; diphenyliodonium hexafluorophosphate, diaryliodonium salts such as diphenyliodonium hexafluoroantimonate; triphenylsulfonium hexafluorophosphate, triphenyl Triarylsulfonium salts such as sulfonium hexafluoroantimonate, diphenyl-4-thiophenoxyphenylsulfonium hexafluorophosphate, diphenyl-4-thiophenoxyphenylsulfonium hexafluoroantimonate, diphenyl-4-thiophenoxyphenylsulfonium pentafluorohydroxyantimonate Triarylselenonium salts such as triphenylselenonium hexafluorophosphate, triphenylselenonium tetrafluoroborate, triphenylselenonium hexafluoroantimonate; dimethylphenacylsulfonium hexafluoroantimonate, diethylphenacylsulfonium hexafluoroantimonate Dialkylphenacylsulfonium salts such as; 4-hydroxyphenyldimethylsulfonium hexafluoroantimonate, dihydroxy-4-hydroxy salts such as 4-hydroxyphenylbenzylmethylsulfonium hexafluoroantimonate; α-hydroxymethylbenzoinsulfonic acid ester, N- Examples thereof include sulfonic acid esters such as hydroxyimide sulfonate, α-sulfonyloxyketone and β-sulfonyloxyketone, and these cationic polymerization initiators may be used alone or in combination of two or more kinds. Further, it can be used in combination with a suitable sensitizer.

Among them, when the adhesive layer requires strict insulation and insulation reliability, it is preferable to use a photoradical initiator, and among them, benzoin ketal such as 2,2-dimethoxy-1,2-diphenylethan-1-one. 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane Α-hydroxyketone such as 1-one; benzophenone, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone , 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, etc. Quinone compounds; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether and other benzoin ethers; benzoin, methylbenzoin, ethylbenzoin and other benzoin compounds; benzyl dimethyl ketal and other benzyl compounds; 9-phenylacridine, 1,7-bis Acridine compounds such as (9,9'-acridinylheptane); N-phenylglycine, coumarin and the like are preferable because of excellent storage stability of the expanded tape, and further 2,2-dimethoxy-1,2-diphenylethane- 1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl- 1-propan-1-one and benzophenone are more preferable because they can be handled under a general ultraviolet light-shielding fluorescent lamp and a facility such as a yellow room is not required.

The optimum amount of the photopolymerization initiator is preferably 0.5 to 1.5 parts by mass, although the optimum value varies depending on the intended thickness of the adhesive layer and/or the light source used. If the amount of the photopolymerization initiator is less than 0.5 parts by mass, the peeling force after irradiation with ultraviolet rays will not be sufficiently reduced, and problems will easily occur when the amount of push-up at the time of pickup is low. Even when the amount of the photopolymerization initiator is larger than 1.5 parts by mass, there is no advantage in the characteristics and it is uneconomical.

The thickness of the adhesive layer is usually 1 to 100 μm, preferably 2 to 50 μm, more preferably 5 to 40 μm. By setting the thickness of the adhesive layer to 1 μm or more, a sufficient adhesive force with the semiconductor chip can be secured, so that the scattering of the semiconductor chip can be more highly prevented during the tape expanding step. On the other hand, even if the thickness exceeds 100 μm, there is no advantage in characteristics and it is uneconomical.

If the adhesive layer has a thickness of 10 μm or more, the base film is not damaged (cuts or the like) even if the semiconductor wafer is diced on the expand tape without using the dicing tape, so that the semiconductor is diced on the dicing tape in the preparation step. The step of dicing the wafer and transferring (attaching) it to the expanding tape can be omitted.

(Method for making expanded tape)
Expanded tapes can be manufactured according to techniques well known in the art. For example, it can be manufactured according to the following method. By coating a varnish containing an adhesive component and a solvent by a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, a curtain coating method or the like on the protective film, and removing the solvent. Form an adhesive layer. Specifically, it is preferable to perform heating at 50 to 200° C. for 0.1 to 90 minutes. If there is no effect on the occurrence of voids or viscosity adjustment in each step, it is preferable to set the conditions under which the organic solvent volatilizes to 1.5% or less.
The produced protective film with an adhesive layer and the substrate film are laminated under a temperature condition of room temperature to 60°C so that the adhesive layer and the substrate film face each other.

-Expand tape (base film, or base film + adhesive layer) is used after removing the protective film.

Examples of the protective film include A-63 (manufactured by Teijin DuPont Films Ltd., release treatment agent: modified silicone type), A-31 (manufactured by Teijin DuPont Films Ltd., release treatment agent: Pt type silicone type) and the like. Is mentioned.
The thickness of the protective film is appropriately selected within a range that does not impair the workability, and is usually preferably 100 μm or less from the economical viewpoint. The thickness of the protective film is preferably 10 to 75 μm, more preferably 25 to 50 μm. When the thickness of the protective film is 10 μm or more, problems such as tearing of the film during the production of the expanded tape are unlikely to occur. When the thickness of the protective film is 75 μm or less, the protective film can be easily peeled off when using the expanded tape.

(Career)
The carrier is not particularly limited as long as it can withstand the temperature and pressure at the time of transfer (the chips are not damaged, the chip interval does not change), and the temperature and pressure at the time of sealing can be endured. For example, when the sealing temperature is 100 to 200° C., it is preferable that the sealing material has heat resistance to withstand the temperature range. The coefficient of thermal expansion is preferably 100 ppm/° C. or lower, more preferably 50 ppm/° C. or lower, still more preferably 20 ppm/° C. or lower. If the coefficient of thermal expansion is large, problems such as displacement of the semiconductor chip occur. Further, the coefficient of thermal expansion is preferably 3 ppm/° C. or higher because distortion or warpage occurs when the coefficient of thermal expansion is smaller than that of the semiconductor chip.

The material of the carrier is not particularly limited, but examples thereof include silicon (wafer), glass, SUS, iron, Cu, etc. plates, and glass epoxy substrates.

The thickness of the carrier may be 100 to 5000 μm, preferably 100 to 4000 μm, more preferably 100 to 3000 μm. When it is 100 μm or more, handleability is improved. Even if it is thick, no remarkable improvement in handleability can be expected. From the economical viewpoint, the thickness may be 5000 μm or less.

The carrier may consist of multiple layers. In addition to the above-mentioned layer that bears heat resistance and handleability, an adhesive layer or a layer obtained by laminating a temporary fixing material may be provided from the viewpoint of imparting adhesion control. The adhesive force may be appropriately set in consideration of the adhesive force of the semiconductor chip or the expanded tape. The thickness is not particularly limited, but may be, for example, 1 to 300 μm, preferably 1 to 200 μm. When the thickness is 1 μm or more, a sufficient adhesive force with the semiconductor chip can be secured. On the other hand, even if the thickness exceeds 300 μm, there is no advantage in characteristics and it is uneconomical.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

(Preparation of acrylic resin solution)
1000 ml of ethyl acetate, 650 g of 2-ethylhexyl acrylate, 350 g of 2-hydroxyethyl acrylate, and 3.0 g of azobisisobutyronitrile were mixed into an autoclave with a capacity of 4000 ml equipped with a three-one motor, a stirring blade and a nitrogen introducing tube, and uniformly mixed. After stirring until, the nitrogen bubbling was performed at a flow rate of 100 ml/min for 60 minutes to degas the dissolved oxygen in the system. The temperature was raised to 60° C. over 1 hour, and after the temperature was raised, polymerization was carried out for 4 hours. Thereafter, the temperature was raised to 90° C. over 1 hour, the temperature was further maintained at 90° C. for 1 hour, and then cooled to room temperature.
Next, 1000 g of ethyl acetate was added and stirred to dilute. To this, 0.1 g of methquinone as a polymerization inhibitor and 0.05 g of dioctyltin dilaurate as a urethane-forming catalyst were added, and then 100 g of 2-methacryloxyethyl isocyanate (Karenzu MOI (registered trademark) manufactured by Showa Denko KK) was added. added. After reacting at 70° C. for 6 hours, it was cooled to room temperature. Thereafter, ethyl acetate was added to adjust the nonvolatile content in the acrylic resin solution to be 35% by mass to obtain an acrylic resin solution having a chain-polymerizable functional group.
When the acid value and the hydroxyl value of this resin were measured according to JIS K0070, no acid value was detected and the hydroxyl value was 121 mgKOH/g.
Further, the obtained acrylic resin solution was vacuum dried overnight at 60° C., and the obtained solid content was subjected to elemental analysis by a fully automatic elemental analyzer (VarioEL manufactured by Elemental Co., Ltd.). When the content of 2-methacryloxyethyl isocyanate introduced into the acrylic resin was calculated from the measured nitrogen content, it was 0.59 mmol/g.
In addition, SD-8022/DP-8020/RI-8020 (manufactured by Tosoh Corporation) is used, and the column is Gelpack GL-A150-S/GL-A160-S (manufactured by Hitachi Chemical Co., Ltd.) and eluted. As a result of GPC measurement using tetrahydrofuran as the liquid, the polystyrene-converted weight average molecular weight was 420,000.

(Example 1)
0.1 part by mass of polyfunctional isocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L, solid content 75%) as a cross-linking agent with respect to the acrylic resin solution (solid content: 100 parts by mass) as a solid content, photopolymerization initiation 1.0 mass part of 1-hydroxycyclohexyl phenyl ketone (manufactured by BASF Corporation, Irgacure 184) was added as an agent, and 2-butanone was further added so that the total solid content was 25 mass %, and the mixture was stirred uniformly for 10 minutes. .. Then, the obtained solution was applied onto a protective film (surface release-treated polyethylene terephthalate, thickness 25 μm) and dried to form an adhesive layer. At this time, the thickness of the adhesive layer when dried was set to 10 μm. Furthermore, the adhesive layer surface was laminated on a substrate film (thickness 100 μm). Then, the obtained tape was aged at 40° C. for 4 days.

In addition, as the above-mentioned substrate film, Himilan 1706 (Mitsui DuPont Polychemical Co., Ltd., ionomer resin), ethylene/1-hexene copolymer and butene/α-olefin copolymer, and Himilan 1706 are listed in this order. A laminated three-layer resin film was used.
The pressure-sensitive adhesive layer, the protective film, and the base film were laminated with a roll laminator at 40° C. to form a protective film/adhesive layer/base film in this order. When used as an expanded tape, the protective film was peeled off before use.

<Production of individual semiconductor chips on expanded tape (step 1)>
An 8-inch silicon wafer (thickness: 250 μm) is laminated on a dicing tape attached to a 12-inch dicing ring at 40° C. using a laminating device (V130, manufactured by Nikko Materials Co., Ltd.) to obtain a size of 1 mm×1 mm. Dicing was performed with a blade using a dicing device (DFD3360, manufactured by Disco Corporation). Then, using a UV exposure machine (ML-320FSAT, manufactured by Mikasa Co., Ltd.), UV was irradiated at 300 mJ to reduce the adhesive force of the dicing tape. After that, the individual semiconductor chips are transferred to an expanding tape attached to a 12-inch dicing ring (V130, manufactured by Nikko Materials Co., Ltd.) (40° C./0.5 MPa/10 seconds) Conditions). A sample obtained by removing the dicing tape after the transfer was used as a sample to be expanded, and the 12-inch dicing ring was set in the expand. At this time, the initial semiconductor chip interval was about 50 μm.

<Step 2>
The sample obtained in the step 1 was set in a 12-inch expander device (MX-5154FN, manufactured by Omiya Kogyo Co., Ltd.) and pushed up by 85 mm at a pushing speed of 100 mm/sec and a temperature (stage temperature) of 50° C. to stretch the expanded tape. .. At this time, the semiconductor chip interval has expanded from about 50 μm at the initial stage to about 500 μm.
<Step 3>
The sample obtained by stretching the expand tape in step 2 was fixed with a grip ring for a 12-inch expander (GR-12, manufactured by Technovision Co., Ltd.) to maintain the tension.
<Step 4>
After irradiating UV (UV exposure machine ML-320FSAT, manufactured by Mikasa Co., Ltd.) to the sample whose tension is held in step 3, the semiconductor chip surface is used as a carrier by using a vacuum laminator (V130, manufactured by Nikko Materials Co., Ltd.). Was laminated. The laminating conditions were a diaphragm temperature of 60° C., a stage temperature of 60° C., a pressure of 0.5 MPa and 60 seconds.
<Step 5>
Only the expanded tape was peeled off from the sample laminated with the carrier in step 4 to prepare a sample in which semiconductor chips were arranged on the carrier (temporary fixing material).

The carrier produced in the following method was used as the carrier in step 4.
A 12-inch silicon wafer (thickness: 775 μm) is laminated with Riva Alpha 3195V (manufactured by Nitto Denko Corporation) as a temporary fixing material using a vacuum laminator (V130, manufactured by Nikko Materials Co., Ltd.), and then externally processed into a wafer shape to be a carrier. Was produced. The lamination conditions were a diaphragm temperature of 80° C., a stage temperature of 40° C., a time of 60 seconds, and a pressure of 0.5 MPa.

<Example 2 and Comparative Examples 1 and 2>
Example 2 and Comparative Examples 1 and 2 were carried out in the same manner as in Example 1 except that the amount of the crosslinking agent used was changed as shown in Table 1.

(Example 3)
Example 3 was carried out in the same manner as Example 2 except that the size of dicing in Step 1 was changed to 0.7 mm×0.7 mm.

<Comparative example 3>
Comparative Example 3 was carried out in the same manner as in Example 3 except that the amount of the crosslinking agent used was changed as shown in Table 1.

<Evaluation method>
(Peel strength)
The peel strength against SUS of the expanded tapes used in Examples 1 to 3 and Comparative Examples 1 to 3 was measured by the following method.
UV pre-irradiation sample in which an expand tape was attached to a SUS 0.5 mm thick laminator GK-13DX (manufactured by Lamy Corporation) at a laminating temperature of 40° C., and a UV exposure device for the pre-UV irradiation sample. (ML-320FSAT manufactured by Mikasa Co., Ltd.) was used to irradiate the expanding tape with ultraviolet rays under the conditions of an ultraviolet wavelength of 365 nm and an exposure amount of 300 mJ/cm ² to prepare a sample after UV irradiation. The peel strength of each of the sample before UV irradiation and the sample after UV irradiation was measured by a method according to JIS C 5016 (1994-strength of peeling of conductor).

(I) Evaluation of Transfer Rate of Semiconductor Chip from Dicing Tape to Expanding Tape In step 1, the transfer rate when the semiconductor chip was transferred from the dicing tape to the expanding tape was evaluated by visually counting the untransferred chips. The case where the semiconductor chip was 100% transferred was designated as A, and the case where there was transfer residue was designated as B.
(Ii) Evaluation of chip jump during expansion The chip jump during expansion was evaluated by visually counting the chip skips after step 2. In addition, the case where there was no chip flying was A, and the case where there was chip flying was B.
(Iii) Evaluation of Transfer Rate of Semiconductor Chip from Expanded Tape to Temporary Fixing Material In steps 4 and 5, the transfer rate when the semiconductor chip is transferred from the expanding tape to the temporary fixing material is to visually count the untransferred chips. It was evaluated by. The case where the semiconductor chip was 100% transferred was designated as A, and the case where there was transfer residue was designated as B.

Table 1 shows the results of evaluating Examples 1 to 3 and Comparative Examples 1 to 3 by the above evaluation method.

As is clear from the results in Table 1, according to Examples 1 to 3 using the predetermined expand tape, even when the chip size was as small as 0.49 to 1.00 mm ² , the dicing tape was used. The transfer rate of the semiconductor chip to the expand tape, the suppression of chip jump during expansion, and the transfer rate of the semiconductor chip from the expand tape to the temporary fixing material are all good.

1... Expanded tape, 1a... Adhesive layer, 1b... Base film, 2... Semiconductor chip, 3... Pad (circuit), 4... Fixing jig, 5... Carrier.

Claims

A tape expanding step of expanding the interval between the plurality of semiconductor chips fixed on the expanded tape from 100 μm or less to 300 μm or more by drawing the expanded tape while heating, and an ultraviolet ray for irradiating the drawn expanded tape with ultraviolet rays. An expanding tape used in a method of manufacturing a semiconductor device, comprising an irradiation step and a peeling step of peeling the expanded tape irradiated with ultraviolet rays from a plurality of the semiconductor chips,
An expanded tape in which the peel strength of the expanded tape before irradiation with ultraviolet rays is 6 N/25 mm or more and the peel strength after irradiation of ultraviolet rays is 0.4 N/25 mm or less.
The expanded tape according to claim 1, which has a base material layer and an adhesive layer.
The expanded tape according to claim 2, wherein the adhesive layer is composed of an ultraviolet curable adhesive.
The adhesive layer comprises an acrylic copolymer having a radiation-curable carbon-carbon double bond-containing group and a hydroxyl group in the main chain, a cross-linking agent having two or more functional groups capable of reacting with the hydroxyl group, and photopolymerization. The expand tape according to claim 2, further comprising an initiator, wherein the content of the cross-linking agent is 0.05 to 0.3 parts by mass with respect to 100 parts by mass of the acrylic copolymer.
The expanded tape according to claim 4, wherein the cross-linking agent is a cross-linking agent having two or more isocyanate groups.
The expanded tape according to claim 4 or 5, wherein the content of the photopolymerization initiator is 0.5 to 1.5 parts by mass with respect to 100 parts by mass of the acrylic copolymer.
A tape expanding step of expanding the interval between a plurality of semiconductor chips fixed on the expand tape from 100 μm or less to 300 μm or more by stretching the expand tape according to any one of claims 1 to 6 while heating. A method of manufacturing a semiconductor device, comprising: an ultraviolet irradiation step of irradiating the stretched expanded tape with ultraviolet rays; and a peeling step of peeling the expanded tape irradiated with ultraviolet rays from the plurality of semiconductor chips.
A method of manufacturing a semiconductor device having a semiconductor chip, comprising:
A preparatory step of preparing the expand tape according to any one of claims 1 to 6, and a plurality of semiconductor chips fixed on the expand tape,
A tape-expanding step of expanding the interval between the plurality of semiconductor chips fixed on the expandable tape from 100 μm or less to 300 μm or more by stretching the expandable tape,
A tension holding step of holding the tension of the stretched expanded tape,
An ultraviolet irradiation step of irradiating the stretched expanded tape with ultraviolet rays,
A transfer step of transferring to the carrier so that the surface of the plurality of semiconductor chips opposite to the surface fixed on the stretched expand tape is fixed.
A peeling step of peeling the expanded tape irradiated with ultraviolet rays from the semiconductor chip,
A method for manufacturing a semiconductor device, comprising: