JP7409029B2 - Method for manufacturing semiconductor devices, integrated dicing/die bonding film, and method for manufacturing the same - Google Patents

Description

The present disclosure relates to a method for manufacturing a semiconductor device, a dicing/die bonding integrated film, and a method for manufacturing the same.

A semiconductor device is manufactured through the following steps. First, a dicing process is performed with a dicing adhesive film attached to the wafer. After that, an expanding process, a pickup process, a die bonding process, etc. are performed.

In the manufacturing process of semiconductor devices, a film called a dicing/die bonding integrated film is used. This film has a structure in which a base material layer, an adhesive layer, and an adhesive layer are laminated in this order, and is used, for example, as follows. First, the wafer is diced with the adhesive layer side surface attached to the wafer and the wafer fixed with a dicing ring. As a result, the wafer is diced into a large number of chips. Next, the adhesive force of the adhesive layer to the adhesive layer is weakened by irradiating the adhesive layer with ultraviolet rays, and then the chip is removed from the adhesive layer together with the adhesive pieces obtained by separating the adhesive layer into pieces. Pick up. Thereafter, a semiconductor device is manufactured through a step of mounting the chip on a substrate or the like via an adhesive piece. Note that a laminate consisting of a chip obtained through the dicing process and an adhesive piece attached to the chip is called a chip with an adhesive piece.

As mentioned above, the adhesive layer (dicing film) whose adhesive strength is weakened by irradiation with ultraviolet rays is called a UV-curable adhesive layer. On the other hand, an adhesive layer whose adhesive strength remains constant without being irradiated with ultraviolet rays during the manufacturing process of a semiconductor device is called a pressure-sensitive adhesive layer. For users (mainly semiconductor device manufacturers), the integrated dicing/die bonding film with a pressure-sensitive adhesive layer does not require the process of irradiating ultraviolet rays, nor does it require any equipment for this purpose. There are benefits. Patent Document 1 can be said to be a UV-curing type in that the adhesive layer contains a component that is cured by ultraviolet rays, but only a predetermined portion of the adhesive layer is irradiated with ultraviolet rays in advance, and the user is not allowed to use the semiconductor device. Disclosed is a dicing die-bonding film that can be said to be pressure-sensitive in that it does not require irradiation with ultraviolet rays during the manufacturing process.

Patent No. 4443962

The adhesive layer of the dicing/die bond integrated film is required to have high adhesion to the adhesive layer and the dicing ring during the dicing process. If the adhesive strength of the adhesive layer is insufficient, peeling will occur between the adhesive layers as the dicing blade rotates at high speed, and the adhesive layer will break, causing pieces of the adhesive layer to scatter. A phenomenon occurs. This phenomenon is called "DAF jump". Note that DAF means die attach film. Alternatively, a phenomenon occurs in which the dicing ring peels off from the adhesive layer due to the flow of cutting water (hereinafter, this phenomenon is referred to as "ring peeling"). In addition, in recent years, as wafers become thinner, the number of processes in which wafers and adhesive layers are separated into pieces by cooling expansion has increased. If the adhesive strength of the adhesive layer is insufficient even during the cooling expansion process, the impact and stress during expansion may cause the outer periphery of the DAF to break, resulting in the phenomenon of scattering of pieces (DAF flying) or the adhesive falling off. Peeling between the edge of the chip and the adhesive layer (chip edge peeling) may occur, causing problems in subsequent steps.

By the way, users of dicing and die-bonding integrated films have a need to perform irradiation with activation energy rays (for example, ultraviolet rays) under as constant conditions as possible. Therefore, for example, even if the adhesive force of the adhesive layer changes due to a change in the formulation of the dicing/die-bonding integrated film, users are required to flexibly adjust the activation energy ray irradiation conditions. is in a difficult situation.

The present disclosure provides a dicing/die bonding integrated film that is user-friendly and useful for efficiently manufacturing semiconductor devices, and a method for manufacturing the same. The present disclosure also provides a method for manufacturing a semiconductor device using the above-described integrated dicing and die bonding film.

One aspect of the present disclosure relates to a method for manufacturing a semiconductor device. This manufacturing method includes the following steps.
(A) A base material layer, an adhesive layer, and an adhesive layer are laminated in this order, and the adhesive layer has a first region whose adhesion to the adhesive layer has been reduced by irradiation with active energy rays. (B) Step of stealth dicing or half-cutting the wafer with a blade (C) Attaching the wafer to the area corresponding to the first area on the adhesive layer Step (D) Expanding the base material layer under cooling conditions to obtain adhesive-attached chips in which the wafer and the adhesive layer are separated into pieces Step (E) Irradiating the adhesive layer with activation energy rays (F) picking up the adhesive-attached chip from the adhesive layer with the base layer expanded; (G) picking up the adhesive-attached chip from the adhesive layer; , the process of mounting on a substrate or other chip, and the dicing/die bonding integrated film in the step (A) is measured at a temperature of 23°C, a peeling angle of 30°, and a peeling speed of 60 mm/min. The adhesive force of the first region to the layer is 6.0 N/25 mm or more and 12.5 N/25 mm or less.

According to the above manufacturing method, a dicing/die bonding integrated film is used in which the adhesive force of the adhesive layer to the adhesive layer is adjusted in advance by irradiation with active energy rays (first irradiation), and Irradiation with activation energy rays (second irradiation) reduces the adhesion of the adhesive layer to the adhesive-attached chip. Therefore, the occurrence of DAF flying or chip edge peeling in the step (D) can be sufficiently suppressed, and excellent pick-up properties can be achieved in the step (F).

The adhesive-attached chip obtained in step (D) may be relatively large in size. That is, the adhesive chip with one piece may have a square or rectangular shape when viewed from above, and may have sides of 6.0 mm or more. Chips with adhesive chips that are relatively large in size tend to warp, which causes the chips with adhesive chips to peel off in the step (D), and the chips tend to crack or pick up defects in the step (F). According to the manufacturing method according to the present disclosure, these defects in the step (F) can be sufficiently suppressed.

The adhesive layer may have a second region that has greater adhesive strength to the adhesive layer than the first region. In this case, the dicing ring can be attached to the second region at the same time as the step (C) or before the step (D).

A dicing/die bonding integrated film according to one aspect of the present disclosure includes a base material layer, an adhesive layer, and is arranged between the base material layer and the adhesive layer. an adhesive layer having a first region in which the adhesive strength has been reduced in advance, and the first region for the adhesive layer is measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min. The adhesive force is 6.0 N/25 mm or more and 12.5 N/25 mm or less.

In this dicing/die bonding integrated film, the adhesive strength of the adhesive to the adhesive layer is adjusted in advance by irradiation with active energy rays. For example, even if the adhesive strength of the adhesive layer changes due to a change in the formulation of a dicing/die-bonding integrated film, the manufacturer of the film can adjust the adhesive strength in advance and provide it to the user, so that the user can be active. Manufacturing of semiconductor devices can be continued under the previous conditions without changing the irradiation conditions of the energy beam.

From the viewpoint of excellent pick-up properties, the above-mentioned dicing/die bonding integrated film has a peeling angle of 30° and a peeling speed at a temperature of 23°C after the ^first region is irradiated with ultraviolet rays in an amount of 150 mJ/cm2. It is preferable that the adhesive force of the first region to the adhesive layer is 1.2 N/25 mm or less, measured under the condition of 60 mm/min. The above-mentioned dicing/die bonding integrated film can be applied to a semiconductor device manufacturing process that includes a step of dividing a wafer into a plurality of chips with an area of 30 to 250 mm ² .

One aspect of the present disclosure relates to a method for manufacturing the above-mentioned dicing/die bonding integrated film. The first aspect of this manufacturing method is to form an adhesive layer on the surface of the base material layer, which is made of a composition whose adhesive strength decreases when irradiated with active energy rays, and a pressure-sensitive adhesive layer formed on the surface of the adhesive layer. The method includes, in this order, a step of producing a laminate including a pressure-sensitive adhesive layer and a step of irradiating active energy rays to a region to be a first region of the adhesive layer included in the laminate. On the other hand, the second aspect of this manufacturing method includes the steps of forming an adhesive layer on the surface of the base layer, which is made of a composition whose adhesive strength is reduced by irradiation with active energy rays, and forming an adhesive layer on the surface of the base material layer. The method includes, in this order, a step of irradiating a region to be the first region with active energy rays, and a step of laminating an adhesive layer on the surface of the adhesive layer after being irradiated with active energy rays.

According to the present disclosure, there is provided a dicing/die bonding integrated film that is user-friendly and useful for efficiently manufacturing semiconductor devices, and a method for manufacturing the same. Further, according to the present disclosure, there is provided a method for manufacturing a semiconductor device using the above-mentioned dicing/die bonding integrated film.

FIG. 1(a) is a plan view showing an embodiment of a dicing/die bonding integrated film, and FIG. 1(b) is a schematic cross-sectional view taken along the line BB shown in FIG. 1(a). FIG. 2 is a schematic diagram showing a state in which a dicing ring is attached to the peripheral edge of the adhesive layer of the dicing/die bonding integrated film, and a wafer is attached to the surface of the adhesive layer. FIG. 3 is a cross-sectional view schematically showing how the 30° peel strength of the adhesive layer with respect to the adhesive layer is measured. FIG. 4 is a schematic cross-sectional view of one embodiment of a semiconductor device. FIGS. 5(a) and 5(b) are cross-sectional views schematically showing the process of manufacturing a chip with adhesive. FIGS. 6(a) to 6(c) are cross-sectional views schematically showing the process of manufacturing a chip with adhesive. 7(a) and 7(b) are cross-sectional views schematically showing the process of manufacturing the semiconductor device shown in FIG. 4.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In the following description, the same or corresponding parts are given the same reference numerals, and overlapping description will be omitted. Note that the present invention is not limited to the following embodiments. In this specification, (meth)acrylic means acrylic or methacryl.

<Dicing/die bonding integrated film>
FIG. 1(a) is a plan view showing an integrated dicing/die bonding film according to the present embodiment, and FIG. 1(b) is a schematic cross-sectional view taken along line BB in FIG. The dicing/die bonding integrated film 10 (hereinafter simply referred to as "film 10" in some cases) has a base material layer 1, a first surface F1 facing the base material layer 1, and a second surface F1 on the opposite side. The adhesive layer 3 having the surface F2 and the adhesive layer 5 provided so as to cover the center of the second surface F2 of the adhesive layer 3 are provided in this order. In this embodiment, a mode in which one laminate of the adhesive layer 3 and the adhesive layer 5 is formed on the square base material layer 1 is illustrated, but the base material layer 1 has a predetermined length ( For example, the laminate of the adhesive layer 3 and the adhesive layer 5 may be arranged at a predetermined interval so as to be lined up in the longitudinal direction.

(Adhesive layer)
The adhesive layer 3 has a first region 3a including at least a region Rw corresponding to the attachment position of the wafer W on the adhesive layer 5, and a second region 3b located so as to surround the first region 3a. . The broken line in FIGS. 1(a) and 1(b) indicates the boundary between the first region 3a and the second region 3b. The first region 3a and the second region 3b are made of the same composition before irradiation with active energy rays. The first region 3a is a region whose adhesive strength is lower than that of the second region 3b by being irradiated with active energy rays such as ultraviolet rays. The second region 3b is a region to which the dicing ring DR is attached (see FIG. 2). The second region 3b is a region that is not irradiated with active energy rays and has high adhesive strength to the dicing ring DR.

The adhesive force of the first region 3a to the adhesive layer 5 is 6.0 N/25 mm or more and 12.5 N/25 mm or less. This adhesive strength is a 30° peel strength measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min. FIG. 3 is a cross-sectional view schematically showing how the 30° peel strength of the adhesive layer 3 is measured with the adhesive layer 5 of the measurement sample (width 25 mm x length 100 mm) fixed on the support plate 80. It is. By setting the adhesive strength (30° peel strength) of the first region 3a to the adhesive layer 5 within the above range, DAF flying or chip edge peeling during cooling expansion can be sufficiently suppressed. This makes it possible to manufacture semiconductor devices with a sufficiently high yield. The lower limit of this adhesive force may be 6.5 N/25 mm or 7.0 N/25 mm, and the upper limit may be 11.5 N/25 mm or 10.5 N/25 mm.

The adhesive force of the first region 3a to the adhesive layer 5 is 1.2 N/25 mm or less after the first region 3a is irradiated with ultraviolet rays (main wavelength: 365 nm) in an amount of 150 mJ/cm ² It is preferably 0.4 N/25 mm or more and 1.2 N/25 mm or less, or 0.5 N/25 mm or more and 1.1 N/25 mm or less. According to the film 10 including such an adhesive layer 3, excellent pick-up properties can be achieved. Note that this adhesive strength is a 30° peel strength measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min, as described above (see FIG. 3).

The adhesion force of the second region 3b to the stainless steel substrate is preferably 0.2 N/25 mm or more. This adhesive strength is a 90° peel strength measured at a temperature of 23° C., a peeling angle of 90°, and a peeling speed of 50 mm/min. When this adhesive force is 0.2 N/25 mm or more, ring peeling during dicing can be sufficiently suppressed. The lower limit of this adhesive force may be 0.3 N/25 mm or 0.4 N/25 mm, and the upper limit may be, for example, 2.0 N/25 mm or 1.0 N/25 mm.

The adhesive layer before active energy ray irradiation is made of, for example, an adhesive composition containing a (meth)acrylic resin, a photopolymerization initiator, and a crosslinking agent. The second region 3b that is not irradiated with active energy rays has the same composition as the adhesive layer before irradiation with active energy rays. Hereinafter, the components contained in the adhesive composition will be explained in detail.

[(meth)acrylic resin]
The adhesive composition preferably contains a (meth)acrylic resin having a functional group capable of chain polymerization, and the functional group is preferably at least one selected from an acryloyl group and a methacryloyl group. The content of the functional group in the adhesive layer before active energy ray irradiation is, for example, 0.1 to 1.2 mmol/g, 0.3 to 1.0 mmol/g, or 0.5 to 0.8 mmol/g. It may be g. When the content of the functional group is 0.1 mmol/g or more, it is easy to form a region (first region 3a) in which the adhesive strength is moderately reduced by irradiation with active energy rays, and on the other hand, the content of the functional group is 1.2 mmol/g or more. By being less than g, it is easy to achieve excellent pick-up properties.

(Meth)acrylic resin can be obtained by synthesis using a known method. Examples of the synthesis method include solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, precipitation polymerization, gas phase polymerization, plasma polymerization, and supercritical polymerization. In addition, the types of polymerization reactions include radical polymerization, cationic polymerization, anionic polymerization, living radical polymerization, living cationic polymerization, living anionic polymerization, coordination polymerization, immodal polymerization, etc., as well as ATRP (atom transfer radical polymerization) and RAFTP ( Examples include techniques such as reversible addition-fragmentation chain transfer polymerization). Among these, synthesis by radical polymerization using the solution polymerization method is not only economical, has a high reaction rate, and is easy to control polymerization, but also allows compounding using the resin solution obtained by polymerization as it is. It has the following advantages.

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

There are no particular limitations on the monomer used when synthesizing the (meth)acrylic resin, as long as it has one (meth)acryloyl group in one molecule. Specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, butoxyethyl (meth)acrylate, and 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 Acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethoxypolyethylene glycol ( Aliphatic (meth)acrylates such as meth)acrylate, methoxypolypropylene glycol (meth)acrylate, ethoxypolypropylene glycol (meth)acrylate, mono(2-(meth)acryloyloxyethyl)succinate; cyclopentyl (meth)acrylate, cyclohexyl ( meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, mono(2-(meth)acryloyloxyethyl)tetrahydrophthalate, mono(2-(meth)acrylate) Alicyclic (meth)acrylates such as (royloxyethyl) hexahydrophthalate; benzyl (meth)acrylate, phenyl (meth)acrylate, o-biphenyl (meth)acrylate, 1-naphthyl (meth)acrylate, 2-naphthyl (meth)acrylate; ) acrylate, phenoxyethyl (meth)acrylate, p-cumylphenoxyethyl (meth)acrylate, o-phenylphenoxyethyl (meth)acrylate, 1-naphthoxyethyl (meth)acrylate, 2-naphthoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, phenoxypolypropylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-hydroxy-3-(o-phenylphenoxy)propyl (meth)acrylate, ) acrylate, aromatic (meth)acrylates such as 2-hydroxy-3-(1-naphthoxy)propyl (meth)acrylate, 2-hydroxy-3-(2-naphthoxy)propyl (meth)acrylate; 2-tetrahydrofurfuryl Heterocyclic (meth)acrylates such as (meth)acrylate, N-(meth)acryloyloxyethylhexahydrophthalimide, 2-(meth)acryloyloxyethyl-N-carbazole, caprolactone modified products of these, 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-epoxy Contains ethylenically unsaturated groups and epoxy groups such as heptyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, o-vinylbenzylglycidyl ether, m-vinylbenzylglycidyl ether, p-vinylbenzylglycidyl ether, etc. Compound; (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)acrylate, etc. Compounds having ethylenically unsaturated groups and oxetanyl groups; Compounds having ethylenically unsaturated groups and isocyanate groups such as 2-(meth)acryloyloxyethyl isocyanate; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl ( Examples include compounds having an ethylenically unsaturated group and a hydroxyl group such as meth)acrylate, 4-hydroxybutyl(meth)acrylate, 3-chloro-2-hydroxypropyl(meth)acrylate, and 2-hydroxybutyl(meth)acrylate. The desired (meth)acrylic resin can be obtained by appropriately combining these.

The (meth)acrylic resin preferably has at least one functional group selected from a hydroxyl group, a glycidyl group, an amino group, etc., as a reaction site with a functional group-introducing compound or a crosslinking agent, which will be described later. Monomers for synthesizing (meth)acrylic resins having hydroxyl groups include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-chloro-2 - Compounds having an ethylenically unsaturated group and a hydroxyl group such as hydroxypropyl (meth)acrylate and 2-hydroxybutyl (meth)acrylate can be mentioned, and these can be used alone or in combination of two or more. can.

Monomers for synthesizing (meth)acrylic resins having glycidyl groups include glycidyl (meth)acrylate, α-ethylglycidyl (meth)acrylate, α-propylglycidyl (meth)acrylate, and α-butylglycidyl (meth)acrylate. 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, 3,4-epoxycyclohexylmethyl (meth)acrylate, o-vinylbenzylglycidyl ether, m-vinylbenzylglycidyl ether, p-vinylbenzylglycidyl ether, etc. Examples include compounds having an ethylenically unsaturated group and an epoxy group, and these can be used alone or in combination of two or more.

The (meth)acrylic resin synthesized from these monomers preferably contains a functional group capable of chain polymerization. The chain-polymerizable functional group is, for example, at least one selected from acryloyl and methacryloyl groups. A functional group capable of chain polymerization is introduced into the (meth)acrylic resin synthesized as described above, for example, by reacting the following compound (functional group-introducing compound) with the (meth)acrylic resin synthesized as described above. be able to. Specific examples of functional group-introduced compounds include 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate; diisocyanate compounds or an acryloyl monoisocyanate compound obtained by reacting a polyisocyanate compound with hydroxyethyl (meth)acrylate or 4-hydroxybutylethyl (meth)acrylate; a diisocyanate compound or a polyisocyanate compound, a polyol compound, and hydroxyethyl (meth)acrylate; Examples include acryloyl monoisocyanate compounds obtained by reaction with acrylates. Among these, 2-methacryloyloxyethyl isocyanate is particularly preferred. These compounds can be used alone or in combination of two or more.

[Photopolymerization initiator]
The photopolymerization initiator is not particularly limited as long as it generates active species capable of chain polymerization upon irradiation with active energy rays (at least one selected from ultraviolet rays, electron beams, and visible rays); for example, Examples include photoradical polymerization initiators. The active species capable of chain polymerization herein means those that initiate a polymerization reaction by reacting with a functional group capable of chain polymerization.

Examples of the photoradical polymerization initiator include benzoin ketals such as 2,2-dimethoxy-1,2-diphenylethan-1-one; 1-hydroxycyclohexylphenyl ketone, and 2-hydroxy-2-methyl-1-phenylpropane-1. α-hydroxyketones such as -one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one; 2-benzyl-2-dimethylamino-1- α-aminoketones such as (4-morpholinophenyl)-butan-1-one, 1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one; 1-[4 Oxime esters such as -(phenylthio)phenyl]-1,2-octadione-2-(benzoyl)oxime; bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2 , 4,4-trimethylpentylphosphine oxide, 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-diphenylimidazole 2,4,5-triarylimidazole dimers such as 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; benzophenone, N,N′-tetramethyl-4,4 Benzophenone compounds such as '-diaminobenzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone; 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- Quinone compounds such as phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone; benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether; benzoin, methylbenzoin, ethylbenzoin, etc. Examples include benzoin compounds; benzyl compounds such as benzyl dimethyl ketal; acridine compounds such as 9-phenylacridine and 1,7-bis(9,9'-acridinylheptane); N-phenylglycine and coumarin.

The content of the photopolymerization initiator in the adhesive composition is, for example, 0.1 to 30 parts by mass, and 0.3 to 10 parts by mass, based on 100 parts by mass of the (meth)acrylic resin. The amount is preferably 0.5 to 5 parts by mass, and more preferably 0.5 to 5 parts by mass. If the content of the photopolymerization initiator is less than 0.1 parts by mass, the adhesive layer will be insufficiently cured after irradiation with active energy rays, and pick-up failure will likely occur. If the content of the photopolymerization initiator exceeds 30 parts by mass, contamination of the adhesive layer (transfer of the photopolymerization initiator to the adhesive layer) is likely to occur.

[Crosslinking agent]
The crosslinking agent is used, for example, for the purpose of controlling the elastic modulus and/or tackiness of the adhesive layer. The crosslinking agent may be a compound having two or more functional groups in one molecule that can react with at least one kind of functional group selected from the hydroxyl group, glycidyl group, amino group, etc. that the (meth)acrylic resin has. Examples of the bonds formed by the reaction between the crosslinking agent and the (meth)acrylic resin include ester bonds, ether bonds, amide bonds, imide bonds, urethane bonds, and urea bonds.

In this embodiment, it is preferable to employ a compound having two or more isocyanate groups in one molecule as the crosslinking agent. When such a compound is used, it can easily react with the hydroxyl group, glycidyl group, amino group, etc. that the (meth)acrylic resin has, and form a strong crosslinked structure.

Examples of compounds having two or more isocyanate groups in one molecule include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4 , 4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate Examples include isocyanate compounds such as.

As the crosslinking agent, a reaction product of the above-mentioned isocyanate compound and a polyhydric alcohol having two or more OH groups in one molecule (isocyanate group-containing oligomer) may be employed. Examples of polyhydric alcohols having two or more OH groups in one molecule include ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, Examples include 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, glycerin, pentaerythritol, dipentaerythritol, 1,4-cyclohexanediol, and 1,3-cyclohexanediol.

Among these, as a crosslinking agent, a reaction product (isocyanate group-containing oligomer) of a polyfunctional isocyanate having two or more isocyanate groups in one molecule and a polyhydric alcohol having three or more OH groups in one molecule is used. It is even more desirable that there be one. By using such an isocyanate group-containing oligomer as a crosslinking agent, the adhesive layer 3 forms a dense crosslinked structure, which can sufficiently prevent the adhesive from adhering to the adhesive layer 5 in the pick-up process. .

The content of the crosslinking agent in the adhesive composition may be appropriately set depending on the cohesive force and elongation at break required for the adhesive layer, the adhesiveness with the adhesive layer 5, and the like. Specifically, the content of the crosslinking agent is, for example, 3 to 30 parts by mass, preferably 4 to 15 parts by mass, and preferably 7 to 15 parts by mass, per 100 parts by mass of the (meth)acrylic resin. More preferably, it is 10 parts by mass. By setting the content of the crosslinking agent within the above range, it is possible to achieve a good balance between the properties required for the adhesive layer in the dicing process and the properties required for the adhesive layer 3 in the die bonding process, and Excellent pick-up properties can also be achieved.

If the content of the crosslinking agent is less than 3 parts by mass based on 100 parts by mass of the (meth)acrylic resin, the formation of a crosslinked structure tends to be insufficient, resulting in poor adhesion in the pick-up process. Since the interfacial adhesion with the agent layer 5 is not sufficiently reduced, defects are likely to occur during pickup. On the other hand, if the content of the crosslinking agent exceeds 30 parts by mass per 100 parts by mass of the (meth)acrylic resin content, the adhesive layer 3 tends to become excessively hard, and due to this, in the expanding process. Semiconductor chips peel off easily.

The content of the crosslinking agent based on the total weight of the adhesive composition is, for example, 0.1 to 20% by weight, and may be 3 to 17% by weight or 5 to 15% by weight. When the content of the crosslinking agent is 0.1% by mass or more, it is easy to form a region (first region 3a) in which the adhesive force is moderately reduced by irradiation with active energy rays, while on the other hand, when the content is 15% by mass or less, This makes it easier to achieve excellent pickup performance.

The thickness of the adhesive layer 3 may be appropriately set depending on the conditions of the expanding process (temperature, tension, etc.), and is, for example, 1 to 200 μm, preferably 5 to 50 μm, and 10 to 20 μm. It is more preferable. If the thickness of the adhesive layer 3 is less than 1 μm, the adhesiveness tends to be insufficient, and if it exceeds 200 μm, the kerf width becomes narrow during expansion (relaxing stress when pushing up the pin), and pickup tends to be insufficient. .

The adhesive layer 3 is formed on the base material layer 1. As a method for forming the adhesive layer 3, a known method can be adopted. For example, a laminate of the base layer 1 and the adhesive layer 3 may be formed by a two-layer extrusion method, or a varnish for forming the adhesive layer 3 may be prepared and applied to the surface of the base layer 1. Alternatively, the adhesive layer 3 may be formed on the release-treated film and transferred to the base material layer 1.

The varnish for forming the adhesive layer 3 is preferably prepared using an organic solvent that can dissolve the (meth)acrylic resin, the photopolymerization initiator, and the crosslinking agent, and that evaporates when heated. Specific examples of organic solvents include aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; cyclic ethers such as tetrahydrofuran and 1,4-dioxane; methanol, ethanol, isopropanol, butanol, ethylene glycol, and propylene. Alcohols such as glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone, etc. Ester; carbonic acid ester such as ethylene carbonate, 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 Polyhydric alcohol alkyl ethers such as dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono Polyhydric alcohol alkyl ether acetate such as butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate; N,N-dimethylformamide, N,N-dimethylacetamide, N - Amides such as methylpyrrolidone.

Among these, from the viewpoint of solubility and boiling point, for example, toluene, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, ethylene glycol monomethyl ether, ethylene glycol monomethyl Ethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol dimethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and N,N-dimethylacetamide are preferred. These organic solvents may be used alone or in combination of two or more. The solid content concentration of the varnish is generally preferably 10 to 60% by mass.

(Base material layer)
As the base material layer 1, a known polymer sheet or film can be used, and there is no particular restriction as long as it can be subjected to an expanding process under low temperature conditions. Specifically, as the base material layer 1, crystalline polypropylene, amorphous polypropylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, ultra-low-density polyethylene, low-density linear polyethylene, polybutene, polymethylpentene, etc. Polyolefin, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene- Hexene copolymer, polyester such as polyurethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, fully aromatic polyamide, polyphenylsulfide, aramid (paper), glass , glass cloth, fluororesin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, a mixture of these with a plasticizer, and a cured product crosslinked by electron beam irradiation.

The base material layer 1 has a surface mainly composed of at least one resin selected from polyethylene, polypropylene, polyethylene-polypropylene random copolymer, and polyethylene-polypropylene block copolymer, and this surface and the adhesive layer 3 It is preferable that they are in contact. These resins are good base materials in terms of properties such as Young's modulus, stress relaxation properties, and melting points, as well as from the viewpoints of price and recycling of waste materials after use. The base material layer 1 may be a single layer, but may have a multilayer structure in which layers made of different materials are laminated as necessary. In order to control the adhesion with the adhesive layer 3, the surface of the base layer 1 may be subjected to surface roughening treatment such as matte treatment or corona treatment.

(Adhesive layer)
For the adhesive layer 5, an adhesive composition constituting a known die bonding film can be applied. Specifically, the adhesive composition constituting the adhesive layer 5 preferably contains an epoxy group-containing acrylic copolymer, an epoxy resin, and an epoxy resin curing agent. The adhesive layer 5 containing these components has excellent adhesion between chips and substrates and between chips, and can also provide electrode embeddability and wire embeddability, and can be bonded at low temperatures in the die bonding process. It is preferable because it has characteristics such as being able to obtain excellent curing in a short time and having excellent reliability after molding with a sealant.

Examples of the epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, Bisphenol A novolac type epoxy resin, diglycidyl etherified biphenol, diglycidyl etherified naphthalene diol, diglycidyl etherified phenol, diglycidyl etherified alcohol, and alkyl substituted products and halogenated products thereof. , bifunctional epoxy resins such as hydrogenated products, and novolac type epoxy resins. Other commonly known epoxy resins such as polyfunctional epoxy resins and heterocycle-containing epoxy resins may also be used. These can be used alone or in combination of two or more. Note that components other than the epoxy resin may be included as impurities within a range that does not impair the properties.

Examples of the epoxy resin curing agent include phenolic resins that can be obtained by reacting a phenol compound and a xylylene compound, which is a divalent linking group, without a catalyst or in the presence of an acid catalyst. Phenol compounds used in the production of phenolic resins include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, p-ethylphenol, on-propylphenol, mn-propylphenol, pn-propylphenol, o-isopropylphenol, m-isopropylphenol, p-isopropylphenol, on-butylphenol, mn-butylphenol, pn-butylphenol, o-isobutylphenol, m-isobutylphenol, p-isobutylphenol, octylphenol, nonylphenol, 2,4-xylenol, 2,6-xylenol, 3,5-xylenol, 2,4,6-trimethylphenol, resorcinol, catechol, hydroquinone, 4-methoxyphenol, o-phenyl Phenol, m-phenylphenol, p-phenylphenol, p-cyclohexylphenol, o-allylphenol, p-allylphenol, o-benzylphenol, p-benzylphenol, o-chlorophenol, p-chlorophenol, o-bromo Examples include phenol, p-bromophenol, o-iodophenol, p-iodophenol, o-fluorophenol, m-fluorophenol, and p-fluorophenol. These phenol compounds may be used alone or in combination of two or more. As the xylylene compound which is a divalent linking group used in the production of phenol resin, the following xylylene dihalides, xylylene diglycols and derivatives thereof can be used. That is, α,α′-dichloro-p-xylene, α,α′-dichloro-m-xylene, α,α′-dichloro-o-xylene, α,α′-dibromo-p-xylene, α,α′ -dibromo-m-xylene, α,α′-dibromo-o-xylene, α,α′-diiodo-p-xylene, α,α′-diiodo-m-xylene, α,α′-diiodo-o-xylene , α,α′-dihydroxy-p-xylene, α,α′-dihydroxy-m-xylene, α,α′-dihydroxy-o-xylene, α,α′-dimethoxy-p-xylene, α,α′- Dimethoxy-m-xylene, α,α′-dimethoxy-o-xylene, α,α′-diethoxy-p-xylene, α,α′-diethoxy-m-xylene, α,α′-diethoxy-o-xylene, α,α′-di-n-propoxy-p-xylene, α,α′-di-n-propoxy-m-xylene, α,α′-di-n-propoxy-o-xylene, α,α′- Di-isopropoxy-p-xylene, α,α′-diisopropoxy-m-xylene, α,α′-diisopropoxy-o-xylene, α,α′-di-n-butoxy-p-xylene, α,α′-di-n-butoxy-m-xylene, α,α′-di-n-butoxy-o-xylene, α,α′-diisobutoxy-p-xylene, α,α′-diisobutoxy-m- Xylene, α,α′-diisobutoxy-o-xylene, α,α′-di-tert-butoxy-p-xylene, α,α′-di-tert-butoxy-m-xylene, α,α′-di- Mention may be made of tert-butoxy-o-xylene. These can be used alone or in combination of two or more.

When reacting the above-mentioned phenol compound and xylylene compound, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and polyphosphoric acid; Carboxylic acids; Super strong acids such as trifluoromethanesulfonic acid; Strong acidic ion exchange resins such as alkanesulfonic acid type ion exchange resins; Super strong acidic ion exchange resins such as perfluoroalkanesulfonic acid type ion exchange resins Resins (trade name: Nafion, manufactured by Du Pont, "Nafion" is a registered trademark); Natural and synthetic zeolites; Using acidic catalysts such as activated clay (acidic clay), substantially It is obtained by reacting until the xylylene compound as a raw material disappears and the reaction composition becomes constant. The reaction time depends on the raw materials and the reaction temperature, but is generally about 1 to 15 hours, and can actually be determined while monitoring the reaction composition using GPC (gel permeation chromatography) or the like.

The epoxy group-containing acrylic copolymer is preferably a copolymer obtained by using glycidyl acrylate or glycidyl methacrylate as a raw material in an amount of 0.5 to 6% by mass based on the resulting copolymer. When this amount is 0.5% by mass or more, high adhesive strength can be easily obtained, and on the other hand, when this amount is 6% by mass or less, gelation can be suppressed. The remainder may be an alkyl acrylate or alkyl methacrylate having an alkyl group having 1 to 8 carbon atoms, such as methyl acrylate or methyl methacrylate, and a mixture of styrene, acrylonitrile, or the like. Among these, ethyl (meth)acrylate and/or butyl (meth)acrylate are particularly preferred. The mixing ratio is preferably adjusted in consideration of the Tg of the copolymer. If Tg is less than −10° C., the tackiness of the adhesive layer 5 in the B-stage state tends to increase, and the handleability tends to deteriorate. Note that the upper limit of the glass transition point (Tg) of the epoxy group-containing acrylic copolymer is, for example, 30°C. The polymerization method is not particularly limited, and examples thereof include pearl polymerization and solution polymerization. Examples of commercially available acrylic copolymers containing epoxy groups include HTR-860P-3 (trade name, manufactured by Nagase ChemteX Corporation).

The weight average molecular weight of the epoxy group-containing acrylic copolymer is 100,000 or more, and within this range, adhesiveness and heat resistance are high, and it is preferably 300,000 to 3,000,000, and preferably 500,000 to 2,000,000. is more preferable. When the weight average molecular weight is 3,000,000 or less, it is possible to prevent the filling property between the semiconductor chip and the substrate that supports it from decreasing. The weight average molecular weight is a polystyrene equivalent value determined by gel permeation chromatography (GPC) using a standard polystyrene calibration curve.

The adhesive layer 5 may further contain a curing accelerator such as a tertiary amine, imidazole, or quaternary ammonium salt, if necessary. Specific examples of the curing accelerator include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazolium trimellitate. These may be used alone or in combination of two or more.

The adhesive layer 5 may further contain an inorganic filler if necessary. Specific examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, Examples include crystalline silica and amorphous silica. These may be used alone or in combination of two or more.

The thickness of the adhesive layer 5 is, for example, 1 to 300 μm, preferably 5 to 150 μm, and more preferably 10 to 100 μm. If the thickness of the adhesive layer 5 is less than 1 μm, the adhesiveness tends to be insufficient, while if it exceeds 300 μm, the breakability and pick-up properties during expansion tend to be insufficient.

Note that the adhesive layer 5 may not contain a thermosetting resin. For example, when the adhesive layer 5 contains a reactive group-containing (meth)acrylic copolymer, the adhesive layer 5 contains the reactive group-containing (meth)acrylic copolymer, a curing accelerator, and a filler. It is fine as long as it is something.

<Production method of dicing/die bonding integrated film>
The method for producing the film 10 includes forming on the surface of the base layer 1 an adhesive layer made of an adhesive composition whose adhesive strength is reduced by irradiation with active energy rays, and a pressure-sensitive adhesive layer formed on the surface of the adhesive layer. The method includes, in this order, a step of producing a laminate including the adhesive layer 5 and a step of irradiating the region to become the first region 3a of the adhesive layer included in the laminate with active energy rays. The dose of active energy rays applied to the region that will become the first region 3a is, for example, 10 to 1000 mJ/cm ² , and may be 100 to 700 mJ/cm ² or 200 to 500 mJ/cm ² .

In the above manufacturing method, a laminate of the adhesive layer and the adhesive layer 5 is first produced, and then a specific region of the adhesive layer is irradiated with active energy rays. As described below, the first region 3a may be formed by irradiating the adhesive layer with active energy rays before being bonded to the adhesive layer 5. That is, the method for producing the film 10 includes the steps of forming an adhesive layer on the surface of the base layer 1, which is made of a composition whose adhesive strength decreases when irradiated with active energy rays, and a step of forming the adhesive layer on the surface of the base layer 1. The method includes, in this order, the step of irradiating the region to become the region 3a of No. 1 with active energy rays, and the step of laminating the adhesive layer 5 on the surface of the adhesive layer 3 after irradiating the active energy rays. It's fine.

<Semiconductor device and its manufacturing method>
FIG. 4 is a cross-sectional view schematically showing the semiconductor device according to this embodiment. The semiconductor device 100 shown in this figure includes a substrate 70, four chips S1, S2, S3, S4 stacked on the surface of the substrate 70, an electrode (not shown) on the surface of the substrate 70, and four chips S1. , S2, S3, and S4, and a sealing layer 50 that seals these wires.

The substrate 70 is, for example, an organic substrate, or may be a metal substrate such as a lead frame. From the viewpoint of suppressing warpage of the semiconductor device 100, the thickness of the substrate 70 is, for example, 70 to 140 μm, and may be 80 to 100 μm.

The four chips S1, S2, S3, and S4 are laminated via a cured product 5C of the adhesive piece 5P. The shapes of the chips S1, S2, S3, and S4 in plan view are, for example, square or rectangular. The area of the chips S1, S2, S3, S4 is 30 to 250 mm ² , and may be 40 to 200 mm ² or 50 to 150 mm ² . The length of one side of the chips S1, S2, S3, and S4 is, for example, 6.0 mm or more, and may be 7.0 to 18 mm or 8.0 to 15 mm. The thickness of the chips S1, S2, S3, and S4 is, for example, 10 to 150 μm, and may be 20 to 80 μm. Note that the lengths of one side of the four chips S1, S2, S3, and S4 may be the same or different from each other, and the same applies to the thickness. Furthermore, the four chips S1, S2, S3, and S4 may be relatively small in size. That is, the area of the chips S1, S2, S3, S4 may be less than 30 mm ² , for example 0.1 to 20 mm ² or 1 to 15 mm ² .

The method for manufacturing the semiconductor device 100 includes the following steps.
(A) Step of preparing film 10 (B) Step of stealth dicing or half-cutting wafer W with a blade (C) Step of placing wafer W in region Rw corresponding to the first region in adhesive layer 5 Pasting step (D) Expanding the base material layer 1 under cooling conditions to obtain adhesive-attached chips 8 in which the wafer W and the adhesive layer 5 are separated (E) Adding active to the adhesive layer 3 Step (F) of reducing the adhesion of the adhesive layer 3 to the adhesive-attached chip 8 by irradiating it with energy rays; (F) Picking up the adhesive-attached chip 8 from the adhesive layer 3 with the base layer 1 expanded; (G) Step of mounting the adhesive-attached chip 8 on a substrate or other chip

An example of a method for manufacturing the semiconductor device 100 will be specifically described. First, a protective film (also referred to as BG tape) is attached to the circuit surface Wa of the wafer W. A plurality of scheduled cutting lines L are formed by irradiating the wafer W with a laser (stealth dicing). Thereafter, back grinding and polishing are performed on the wafer W as necessary. Note that although stealth dicing using a laser is illustrated here, the wafer W may be half-cut using a blade instead of this. Half-cutting means not cutting the wafer W, but forming a cut corresponding to the planned cutting line L of the wafer W.

Next, as shown in FIG. 5A, the film 10 is attached to the back surface Wb of the wafer W so that the adhesive layer 5 is in contact with it. Furthermore, a dicing ring DR is attached to the second region 3b of the adhesive layer 3. Thereafter, the wafer W and the adhesive layer 5 are separated into pieces by cooling expansion under a temperature condition of 0 to -15°C. That is, as shown in FIG. 5(b), tension is applied to the base layer 1 by pushing up the inner region 1a of the dicing ring DR in the base layer 1 with the ring Ra. As a result, the wafer W is divided along the planned cutting line L, and the adhesive layer 5 is accordingly divided into adhesive pieces 5P, and a plurality of chips 8 with adhesive pieces are formed on the surface of the adhesive layer 3. is obtained. The adhesive piece attached chip 8 is composed of a chip S and an adhesive piece 5P.

By heating the inner region 1a of the dicing ring DR in the base material layer 1, the inner region 1a is contracted. FIG. 6A is a cross-sectional view schematically showing how the inner region 1a is heated by blowing from the heater H. By annularly contracting the inner region 1a and applying tension to the base material layer 1, the distance between adjacent adhesive chips 8 can be increased. Thereby, the occurrence of pickup errors can be further suppressed, and the visibility of the adhesive-attached chip 8 in the pickup process can be improved.

Next, as shown in FIG. 6(b), the adhesive force of the adhesive layer 3 is reduced by irradiation with activation energy (for example, ultraviolet rays). The amount of active energy ray irradiation to the adhesive layer 3 is, for example, 10 to 1000 mJ/cm ² , and may be 100 to 700 mJ/cm ² or 200 to 500 mJ/cm ² . Thereafter, as shown in FIG. 6(c), the chip 8 with the adhesive chip 8 is pushed up with the push-up jig 42 to peel the chip 8 with the adhesive chip 8 from the adhesive layer 3, and the chip 8 with the adhesive chip 8 is pushed up by the suction collet 44. suction and pick up.

The chip 8 with the adhesive strip is transported to a semiconductor device assembly device (not shown) and is pressure-bonded to a circuit board or the like. As shown in FIG. 7A, the first chip S1 (chip S) is pressure-bonded to a predetermined position on the substrate 70 via the adhesive piece 5P. Next, the adhesive piece 5P is cured by heating. As a result, the adhesive piece 5P is cured to become a cured product 5C. The curing treatment of the adhesive piece 5P may be performed in a pressurized atmosphere from the viewpoint of reducing voids.

In the same manner as the mounting of the chip S1 on the substrate 70, the second stage chip S2 is mounted on the surface of the chip S1. Further, by mounting the third and fourth chips S3 and S4, a structure 60 shown in FIG. 7(b) is manufactured. After electrically connecting the chips S1, S2, S3, S4 and the substrate 70 with the wires W1, W2, W3, W4, the semiconductor element and the wires are sealed with the sealing layer 50, thereby producing the semiconductor device shown in FIG. 100 is completed.

Hereinafter, the present disclosure will be described in more detail based on Examples, but the present invention is not limited to these Examples. In addition, unless otherwise specified, all chemicals used were reagents.

<Example 1>
[Synthesis of acrylic resin]
The acrylic resin blended into the adhesive layer was synthesized as follows. That is, the following ingredients were put into a 2000 ml flask equipped with a three-one motor, a stirring blade, and a nitrogen introduction tube.
・Ethyl acetate (solvent): 635g
・2-ethylhexyl acrylate: 395g
・2-hydroxyethyl acrylate: 100g
・Methacrylic acid: 5g
・Azobisisobutyronitrile: 0.2g

After stirring the contents until they became sufficiently uniform, bubbling was carried out for 60 minutes at a flow rate of 500 ml/min to degas the dissolved oxygen in the system. The temperature was raised to 78°C over 1 hour, and polymerization was carried out for 6 hours after the temperature was raised. Next, the reaction solution was transferred to a pressure cooker with a capacity of 2000 ml equipped with a three-one motor, a stirring blade, and a nitrogen introduction tube, and heated at 120°C and 0.28 MPa for 4.5 hours, then at room temperature (25°C, the same applies hereafter). ).

Next, 490 g of ethyl acetate was added, stirred, and diluted. After adding 0.025 g of methquinone as a polymerization inhibitor and 0.10 g of dioctyltin dilaurate as a urethanization catalyst, 81 g of 2-methacryloxyethyl isocyanate (manufactured by Showa Denko K.K., Karenz MOI (trade name)) was added. After addition, the mixture was reacted at 70°C for 6 hours, and then cooled to room temperature. Thereafter, ethyl acetate was added to adjust the nonvolatile content in the acrylic resin solution to 35% by mass to obtain an acrylic resin solution (A) having a functional group capable of chain polymerization.

The solution containing the acrylic resin (A) obtained as described above was vacuum dried at 60° C. overnight. The solid content thus obtained was subjected to elemental analysis using a fully automatic elemental analyzer (manufactured by Elemental, trade name: varioEL), and the content of the introduced 2-methacryloxyethyl isocyanate was calculated from the nitrogen content. , 0.89 mmol/g.

Furthermore, the weight average molecular weight of the acrylic resin (A) in terms of polystyrene was determined using the following apparatus. That is, SD-8022/DP-8020/RI-8020 manufactured by Tosoh Corporation was used, Gelpack GL-A150-S/GL-A160-S manufactured by Hitachi Chemical Co., Ltd. was used as the column, and tetrahydrofuran was used as the eluent. GPC measurements were performed. As a result, the weight average molecular weight in terms of polystyrene was 350,000.

[Preparation of dicing film]
A varnish for forming an adhesive layer was prepared by mixing the following components. The adhesive layer formed from this varnish is cured by irradiation with ultraviolet rays. The amount of ethyl acetate (solvent) was adjusted so that the total solids content of the varnish was 25% by mass.
・(A) Acrylic resin solution: 100 parts by mass (solid content),
・(B) Photoinitiator (1-hydroxycyclohexyl phenyl ketone, manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure 184, "Irgacure" is a registered trademark): 2.0 parts by mass ・(C) Crosslinking agent (polyfunctional isocyanate, Japan Polyurethane Kogyo Co., Ltd., Coronate L, solid content 75%): 1.1 parts by mass (solid content)
・Ethyl acetate (solvent)

A polyethylene terephthalate film (width: 450 mm, length: 500 mm, thickness: 38 μm), which had been subjected to a release treatment on one side, was prepared. An adhesive layer-forming varnish was applied to the release-treated surface using an applicator, and then dried at 80° C. for 5 minutes. Thereby, a laminate (dicing film) consisting of a polyethylene terephthalate film and an adhesive layer (thickness 10 μm) formed thereon was obtained.

A polyolefin film (width: 450 mm, length: 500 mm, thickness: 100 μm) with one side subjected to corona treatment was prepared. The corona-treated surface and the adhesive layer of the laminate were bonded together at room temperature. Next, the adhesive layer was transferred to a polyolefin film (cover film) by pressing with a rubber roll. Thereafter, a dicing film provided with an adhesive layer was obtained by allowing it to stand at room temperature for 3 days.

[Preparation of die bonding film]
Cyclohexanone was added to the following ingredients and mixed with stirring, followed by kneading for 90 minutes using a bead mill.
・Epoxy resin (YDCN-703 (trade name), manufactured by Nippon Steel Chemical & Materials Co., Ltd., cresol novolac type epoxy resin, epoxy equivalent weight 210, molecular weight 1200, softening point 80°C): 55 parts by mass ・Phenol resin (Milex XLC- LL (product name), manufactured by Mitsui Chemicals, Inc., hydroxyl equivalent: 175, water absorption rate: 1.8%, heating weight loss rate at 350°C: 4%): 45 parts by mass, Silane coupling agent 1 (NUC A-189 (product) 1.7 parts by mass of silane coupling agent 2 (NUCA-1160 (trade name), manufactured by Nippon Unicar Co., Ltd., γ-mercaptopropyltrimethoxysilane): 1.7 parts by mass, γ-ureidopropyltriethoxy Silane) 3:. 2 parts by mass Filler (Aerosil R972 (trade name), manufactured by Nippon Aerosil Co., Ltd., silica, average particle size 0.016 μm): 32 parts by mass The surface of the silica particles is coated with dimethyldichlorosilane and hydrolyzed in a reactor at 400°C.

The following components were added to the mixture of the above components and mixed with stirring. Thereafter, a varnish for forming an adhesive layer was obtained by vacuum degassing.
・Acrylic rubber (HTR-860P-3 (trade name), manufactured by Nagase ChemteX Corporation, content of glycidyl acrylate or glycidyl methacrylate: 3% by mass, weight average molecular weight 800,000): 280 parts by mass ・Curing accelerator (Cure Sol 2PZ-CN (trade name), "Curezol" is a registered trademark, manufactured by Shikoku Kasei Kogyo Co., Ltd., 1-cyanoethyl-2-phenylimidazole): 0.5 parts by mass

A polyethylene terephthalate film (thickness: 35 μm) that had been subjected to a release treatment on one side was prepared. After applying the adhesive layer-forming varnish to the peel-treated surface, it was heated and dried at 140° C. for 5 minutes. Thereby, a laminate (die bonding film) consisting of a polyethylene terephthalate film (carrier film) and an adhesive layer (thickness 10 μm) in a B-stage state formed thereon was obtained.

[Production of integrated dicing and die bonding film]
The die bonding film obtained as described above was cut into a circular shape (diameter: 312 mm) together with the carrier film. A dicing tape with the cover film peeled off was attached to this at room temperature, and then left at room temperature for one day. Thereafter, the dicing tape was cut into a circle (diameter: 370 mm). A region of the adhesive layer of the dicing/die bonding integrated film thus obtained corresponding to the wafer attachment position (the first region of the adhesive layer) was exposed to ultraviolet light using a high-pressure mercury lamp under the following conditions. was irradiated.
・Principal wavelength of ultraviolet rays: 365nm
・Illuminance of ultraviolet rays: 13mW/ ^cm2
・Ultraviolet irradiation amount: 20mJ/ ^cm2
・First area of adhesive layer: circular shape with a diameter of 302 mm

As described above, a dicing/die bonding integrated film according to this embodiment was obtained. In addition, a plurality of integrated dicing and die bonding films were produced for use in various evaluation tests described below.

<Example 2>
A plurality of dicing/die bonding integrated films were obtained in the same manner as in Example 1, except that the amount of ultraviolet irradiation was 30 mJ/cm ² instead of 20 mJ/cm ² .

<Example 3>
When preparing the varnish for forming the adhesive layer, a plurality of dicing and A die bonding integrated film was obtained.

<Comparative example 1>
When preparing the varnish for forming the adhesive layer, a plurality of dicing and A die bonding integrated film was obtained.

<Comparative example 2>
A plurality of dicing/die bonding integrated films were obtained in the same manner as in Example 2, except that the amount of ultraviolet irradiation was 50 mJ/cm ² instead of 30 mJ/cm ² .

<Comparative example 3>
A plurality of integrated dicing and die bonding films were obtained in the same manner as in Example 1, except that ultraviolet irradiation was not performed.

<Comparative example 4>
A plurality of integrated dicing and die bonding films were obtained in the same manner as in Example 3, except that ultraviolet irradiation was not performed.

[Evaluation test]
(1) Measurement of adhesive strength (30° peel strength) of adhesive layer (after first UV irradiation)
The adhesion of the adhesive layer to the adhesive layer of the dicing/die bonding integrated films according to Examples and Comparative Examples was evaluated by measuring 30° peel strength. That is, a sample with a width of 25 mm and a length of 100 mm was cut out from the dicing/die bonding integrated film. The peel strength of the adhesive layer with respect to the adhesive layer was measured using a tensile tester. The measurement conditions were a peeling angle of 30° and a tensile speed of 60 mm/min. Incidentally, the storage of the samples and the measurement of peel strength were performed under an environment of a temperature of 23° C. and a relative humidity of 40%. The dicing/die bonding integrated films according to Examples 1 to 3 and Comparative Examples 1 and 2 were subjected to one UV irradiation. The results are shown in Tables 1 and 2. Although Comparative Examples 3 and 4 were not irradiated with ultraviolet rays in the dicing/die bonding integrated film process, the results are listed in the column of "first ultraviolet irradiation" in Table 2 for convenience.

(2) Measurement of adhesive strength (30° peel strength) of adhesive layer (after second UV irradiation)
The dicing/die bonding integrated films of Examples 1 to 3 and Comparative Examples 1 and 2 were subjected to a second UV irradiation under the following conditions, which corresponds to the second UV irradiation performed before picking up the adhesive-attached chips. was irradiated. Thereafter, the 30° peel strength of the adhesive force of the adhesive layer to the adhesive layer was measured under the same conditions as above. The results are shown in Tables 1 and 2. Comparative Examples 3 and 4 are not irradiated with ultraviolet rays in the process of dicing and die bonding integrated film, so this is the first irradiation of ultraviolet rays, but for convenience, in Table 2, "second irradiation of ultraviolet rays" is shown. The results are listed in the column.
<Second UV irradiation conditions>
・Principal wavelength of ultraviolet rays: 365nm
・Illuminance of ultraviolet rays: 100mW/ ^cm2
・Ultraviolet irradiation amount: 150mJ/ ^cm2

(2) Process performance evaluation (i) Preparation of sample for process performance evaluation A protective tape (BG tape) was attached to the surface of a silicon wafer (diameter: 12 inches, thickness: 775 μm). After that, stealth dicing of the silicon wafer was performed. That is, a modified layer was formed inside the silicon wafer by irradiating the surface (back surface) of the silicon wafer opposite to the side to which the BG tape was attached with laser light under the following conditions.
<Stealth dicing conditions>
・Stealth dicing device: DFL7361 (manufactured by DISCO Co., Ltd.)
・Laser oscillator type: Semiconductor laser pumped Q-switch solid-state laser ・Wavelength: 1342nm
・Frequency: 90kHz
・Output: 1.7W
・Number of passes: 2
・Chip size: 10mm x 10mm
・Dicing speed: 700mm/sec

The silicon wafer after stealth dicing was polished to a thickness of 30 μm. A grinder polisher device (DGP8761, manufactured by DISCO Co., Ltd.) was used for polishing. A dicing/die bonding integrated film was attached to the polished silicon wafer and dicing ring under the following conditions. Thereafter, the BG tape was peeled off from the surface of the silicon wafer.
<Pasting conditions>
・Packing device: DFM2800 (manufactured by DISCO Co., Ltd.)
・Application temperature: 70℃
・Application speed: 10mm/s
・Application tension level: Level 6

Next, using a die separator (DDS2300, manufactured by DISCO Co., Ltd.), the mixture was cooled and expanded under the following conditions. Thereafter, the base material layer (polyethylene terephthalate film) of the dicing/die bonding integrated film was heat-shrinked under the following conditions. Through these steps, the silicon wafer and the adhesive layer were diced into a plurality of chips with adhesive chips (size: 10 mm x 10 mm).
<Cooling expansion conditions>
・Cooling temperature: -15℃
・Cooling time: 120 seconds ・Push-up amount: 12mm
・Push-up speed: 200mm/sec ・Holding time after push-up: 3 seconds <Heat shrink conditions>
・Heater temperature: 220℃
・Heater rotation speed: 5°/sec ・Listing amount: 8mm
・Tape cooling waiting time: 10 seconds

After the silicon wafer and the adhesive layer were cut into pieces, the adhesive layer was irradiated with ultraviolet rays under the following conditions. This cured the adhesive layer and reduced the adhesive force to the adhesive layer.
<Ultraviolet irradiation conditions>
・Illuminance of ultraviolet rays: 100mW/ ^cm2
・Ultraviolet irradiation amount: 150mJ/ ^cm2

(ii) Evaluation of each process property (DAF jump)
After cooling expansion and heat shrinking, DAF jump was evaluated according to the following criteria.
A: DAF jump did not occur at all.
B: DAF did not fly, but peeling or lifting was observed at the interface between the adhesive layer and the pressure-sensitive adhesive layer.
C: DAF skipping occurred in at least one location.

(chip edge peeling)
After cooling expansion and heat shrinking, peeling between the adhesive layer and the pressure-sensitive adhesive layer at the edge portion of the chip with the adhesive piece was evaluated according to the following criteria.
A: No peeling was observed at the edge portion.
B: Peeling was observed at a length of 1 mm or more and less than 2 mm from the edge portion.
C: Peeling of 2 mm or more and less than 3 mm was observed from the edge portion.
D: Peeling of 3 mm or more was observed from the edge portion.

(Separability of adhesive layer)
The entire surface of the silicon wafer after cooling expansion and heat shrinking was observed with a microscope, and the breakability of the adhesive layer was evaluated using the following criteria.
A: The adhesive layer was completely separated.
D: There was an undivided portion in at least one part of the adhesive layer.

(kerf width)
The interval (kerf width) between the chips with the adhesive layer after singulation was measured using a microscope. The kerf widths in the MD/TD direction were each measured at two locations on the outer periphery (top, bottom, left and right) of the silicon wafer and at one location in the center (total of 18 points), and the average value was determined. Evaluation was made based on the following criteria.
S: The average value of the kerf width was 100 μm or more and less than 150 μm.
A: The average value of the kerf width was 70 μm or more and less than 100 μm.
B: The average value of the kerf width was 50 μm or more and less than 70 μm.

(Pickup property)
After carrying out the above evaluation, 100 adhesive-attached chips were picked up under the following conditions.
<Pickup conditions>
・Die bonder device: DB-830P (manufactured by Fasford Technology Co., Ltd.)
- Push-up pin: EJECTOR NEEDLE SEN2-83-05 (diameter: 0.7 mm, tip shape: hemisphere with a radius of 350 μm, manufactured by Micromechanics)
・Push-up height: 250μm
・Push-up speed: 1mm/sec ・Number of push-up pins: 9 <Evaluation criteria>
A: The success rate of pickup was 100%.
B: The success rate of pickup was 80% or more and less than 100%.
C: The success rate of pickup was 60% or more and less than 80%.

The films of Examples 1 to 3 all had good results in processability evaluation. In particular, in Examples 1 and 2, the kerf width was evaluated as "S". Example 3 had a kerf width evaluation of "A", which was the same as Comparative Example 3, but had a better MD/TD balance than Comparative Example 3. Kerf width is one of the important items in the stealth dicing process from the viewpoint of achieving excellent pick-up properties.

DESCRIPTION OF SYMBOLS 1... Base material layer, 3... Adhesive layer, 3a... First region, 3b... Second region, 5... Adhesive layer, 8... Chip with adhesive piece, 10... Dicing/die bonding integrated film, W …wafer

Claims (9)

(A) A first layer in which a base material layer, an adhesive layer, and an adhesive layer are laminated in this order, and the adhesive force of the adhesive layer to the adhesive layer is reduced in advance by irradiation with active energy rays. preparing a dicing/die bonding integrated film having a region;
(B) a step of performing stealth dicing or half-cutting the wafer with a blade;
(C) attaching the wafer to a region of the adhesive layer corresponding to the first region;
(D) expanding the base material layer under cooling conditions to obtain adhesive-attached chips in which the wafer and the adhesive layer are separated;
(E) reducing the adhesive force of the adhesive layer to the adhesive-attached chip by irradiating the adhesive layer with activation energy rays;
(F) picking up the adhesive-attached chip from the adhesive layer while the base layer is expanded;
(G) mounting the adhesive-attached chip on a substrate or other chip;
including;
The dicing/die bonding integrated film in step (A) has an adhesive force of the first region to the adhesive layer measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min. A method for manufacturing a semiconductor device, wherein the pressure is 6.0 N/25 mm or more and 12.5 N/25 mm or less. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the adhesive-attached chip obtained in step (D) has a square or rectangular shape in plan view and has sides of 6.0 mm or more. The adhesive layer has a second region having a greater adhesive force to the adhesive layer than the first region,
3. The method for manufacturing a semiconductor device according to claim 1, wherein a dicing ring is attached to the second region at the same time as the step (C) or before the step (D). a base material layer;
an adhesive layer;
an adhesive layer that is disposed between the base material layer and the adhesive layer and has a first region whose adhesive force to the adhesive layer has been reduced in advance by irradiation with active energy rays;
Equipped with
The adhesive force of the first region to the adhesive layer is 6.0 N/25 mm or more and 12.5 N/25 mm or less, measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min. Integrated dicing and die bonding film. After the first region is irradiated with ultraviolet rays in an amount of 150 mJ/cm ² , the first region of the adhesive layer is measured at a temperature of 23° C., a peeling angle of 30°, and a peeling speed of 60 mm/min. The dicing/die bonding integrated film according to claim 4, wherein the adhesive force in region 1 is 1.2 N/25 mm or less. The dicing/die bonding integrated film according to claim 4 or 5, which is applied to a semiconductor device manufacturing process that includes a step of dividing a wafer into a plurality of chips with an area of 30 to 250 mm ² . The dicing/die bonding integrated film according to any one of claims 4 to 6, wherein the adhesive layer has a second region whose adhesive force to the adhesive layer is greater than that of the first region. A method for manufacturing a dicing/die bonding integrated film according to any one of claims 4 to 7, comprising:
A laminate comprising, on the surface of a base layer, an adhesive layer made of a composition whose adhesive strength decreases when irradiated with active energy rays, and the adhesive layer formed on the surface of the adhesive layer. A process of creating a body,
irradiating a region of the adhesive layer included in the laminate that will become the first region with active energy rays;
A method for manufacturing a dicing/die bonding integrated film, comprising: in this order. A method for manufacturing a dicing/die bonding integrated film according to any one of claims 4 to 7, comprising:
a step of forming an adhesive layer on the surface of the base layer made of a composition whose adhesive strength decreases when irradiated with active energy rays;
irradiating a region of the adhesive layer that will become the first region with active energy rays;
Laminating the adhesive layer on the surface of the adhesive layer after irradiating the active energy ray;
A method for manufacturing a dicing/die bonding integrated film, comprising: in this order.

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