JP2021190695A - Die-bonding film and dicing die-bonding film - Google Patents

Abstract

To provide a die-bonding film and a dicing die-bonding film which can comparatively prevent a void from remaining between wiring boards.SOLUTION: A die-bonding film contains an acrylic resin, a phenolic resin and a filler, in which the filler has a specific surface area of 5 m2/g or more and 100 m2/g or less, and a content mass ratio of the filler to the acrylic resin is 0 or more and 1.50 or less.SELECTED DRAWING: None

Description

The present invention relates to a die bond film and a dicing die bond film.

Conventionally, in the manufacture of semiconductor devices, in order to obtain semiconductor chips for die bonding,
It is known to use a dicing die bond film (for example, Patent Document 1).
The dicing die bond film includes a dicing tape in which a pressure-sensitive adhesive layer is laminated on a base material layer, and a die bond layer (die bond film) in which a pressure-sensitive adhesive layer is releasably laminated on the pressure-sensitive adhesive layer of the dicing tape.

As a method for obtaining a semiconductor chip (die) for die bonding using the dying die bond film, Patent Document 1 describes a half cut in which a groove is formed in the semiconductor wafer so as to be processed into a chip (die) by a cutting process. The process, the back grind process of grinding the semiconductor wafer after the half-cut process to reduce the thickness, and one surface (the surface opposite to the circuit surface) of the semiconductor wafer after the back grind process are attached to the die bond layer. , A mounting process for fixing a semiconductor wafer to a dicing tape, an expanding process for widening the distance between semiconductor chips that have been half-cut, a calf maintenance process for maintaining the distance between semiconductor chips, and a die bond layer and an adhesive layer. It is known to adopt a method having a pickup step of taking out a semiconductor chip in a state where a die bond layer is attached by peeling off the space.

In the pickup step, the semiconductor chip taken out with the die bond layer attached (hereinafter, also referred to as a semiconductor chip with a die bond layer) is adhered to a wiring board as an adherend. The semiconductor chip with a die bond layer is bonded to the wiring board and then electrically connected to the wiring board at a predetermined temperature (for example, 150 ° C.) by wire bonding or the like. The semiconductor chip with a die bond layer and the wiring board are electrically connected by wire bonding or the like, and after being sealed with a sealing resin (after being molded), the sealing resin is cooled to a predetermined temperature. By curing at (for example, 175 ° C.), a semiconductor package is obtained.
Then, the semiconductor package is electrically connected to the motherboard by soldering at a predetermined temperature (for example, 260 ° C.) to form a semiconductor device.

Further, in recent years, there is a further demand for higher performance, lower thickness, and smaller size of the semiconductor device and the semiconductor package. As a measure for satisfying this requirement, the semiconductor chip with a die bond layer is configured to be thin, and the semiconductor chips with a die bond layer configured to be thin are laminated in a plurality of steps in a stepped manner, that is, the die bond is configured to be thin. It has been developed to achieve high-density integration of the semiconductor package and, by extension, high-density integration of the semiconductor device by mounting the layered semiconductor chip in three dimensions.

Japanese Unexamined Patent Publication No. 2019-9203

However, voids may occur between the surface of the wiring board and the surface of the die bond layer, or between the surface of the die bond layer and the surface of the semiconductor chip.
Although the voids can be removed to some extent while the sealing resin is cured at a predetermined temperature, when the number of voids generated between the surface of the wiring board or the like and the surface of the die bond layer becomes relatively large, the voids are said to be present. While the sealing resin is being cured, the voids may not be sufficiently removed.
If the void cannot be sufficiently removed, the moisture in the air is also present in the void in addition to the air, so that the moisture content in the semiconductor package becomes relatively large. In such a case, during soldering at a predetermined temperature (for example, 260 ° C.) for electrically connecting the semiconductor package and the motherboard, the degree of volume expansion due to the vaporization of the water content in the semiconductor package is increased. As the volume increases, the pressure inside the semiconductor package increases significantly due to this large volume expansion. As a result, there is a possibility that the semiconductor package will be destroyed by this large pressure increase (so-called popcorn phenomenon).
However, it cannot be said that sufficient studies have been made on sufficiently suppressing the residual voids between the die bond layer (die bond film) and the wiring board or the like.

Therefore, it is an object of the present invention to provide a dicing die bond film capable of relatively suppressing the residual voids from a wiring board or the like, and a dicing die bond film provided with the die bond film.

As a result of diligent studies by the present inventors, the die bond film is made to contain an acrylic resin, a phenol resin, and a filler, and the specific surface area of the filler is 5 m ² / g or more and 100 m ² / g or less. The present invention has been conceived by finding that by setting the content mass ratio of the filler to the acrylic resin to be larger than 0 and 1.50 or less, it is possible to relatively suppress the residual voids from the wiring substrate and the like. I arrived.

That is, the die bond film according to the present invention is
A die bond film containing an acrylic resin, a phenol resin, and a filler.
The filler has a specific surface area of 5 m ² / g or more and 100 m ² / g or less.
The mass ratio of the filler to the acrylic resin is greater than 0 and 1.50 or less.

According to such a configuration, it is possible to relatively suppress the residual void from the wiring board or the like.

In the die bond film,
The water absorption rate is preferably 0.22% by mass or less.

According to such a configuration, it is possible to further suppress the residual void from the wiring board or the like.

In the die bond film,
The ratio of the value of the parallel line transmittance at the wavelength of 1000 nm to the value of the parallel line transmittance at the wavelength of 250 nm is preferably 2100 or more and 4500 or less.

According to such a configuration, it is possible to further suppress the residual void from the wiring board or the like.

In the die bond film,
The ratio of the thickness of the die-bonded film to the average particle size of the filler is preferably 5 or more and 150 or less.

According to such a configuration, it is possible to further suppress the residual void from the wiring board or the like.

The dicing die bond film according to this embodiment is
A dicing tape in which an adhesive layer is laminated on a base material layer,
A dicing layer laminated on the pressure-sensitive adhesive layer of the dicing tape is provided.
The die bond layer is any of the above die bond films.

According to such a configuration, it is possible to relatively suppress the residual void from the wiring board or the like.

According to the present invention, it is possible to provide a dicing die bond film capable of relatively suppressing residual voids from a wiring board or the like, and a dicing die bond film including the die bond film.

The cross-sectional view which shows the structure of the dicing die bond film which concerns on one Embodiment of this invention. The cross-sectional view which shows the state of the half-cut processing in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the half-cut processing in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the back grind processing in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the back grind processing in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the mounting process in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the mounting process in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the expansion process at a low temperature in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the expansion process at a low temperature in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the expansion process at a low temperature in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the expansion process at room temperature in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the expansion process at room temperature in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the calf maintenance process in the manufacturing method of a semiconductor integrated circuit schematically. The cross-sectional view which shows the state of the pickup process in the manufacturing method of a semiconductor integrated circuit schematically.

Hereinafter, an embodiment of the present invention will be described.

[Die bond film]
The die bond film according to this embodiment contains an acrylic resin, a phenol resin, and a filler.
The die bond film according to the present embodiment preferably contains the acrylic resin in an amount of 40% by mass or more and 60% by mass or less, and preferably contains the phenol resin in an amount of 5% by mass or more and 7% by mass or less. It is preferable that the filler is contained in an amount of 40% by mass or more and 60% by mass or less.

In the die bond film according to the present embodiment, the content mass ratio of the filler to the acrylic resin is larger than 0 and 1.50 or less.

The die bond film according to this embodiment is preferably thermosetting. That is, it is preferable that the die bond film according to the present embodiment contains a thermosetting resin and a curing agent for the thermosetting resin.

Examples of the thermosetting resin include a thermosetting resin and a thermoplastic resin having a thermosetting functional group.

Examples of the thermoplastic resin having a thermosetting functional group include a thermosetting functional group-containing acrylic resin (also referred to as a thermosetting acrylic resin). That is, the acrylic resin may have thermosetting property by containing a thermosetting functional group.
Examples of the acrylic resin in the thermosetting functional group-containing acrylic resin include those containing a monomer unit derived from (meth) acrylic acid ester. In addition, in this specification, "(meth) acrylic" means at least one of "acrylic" and "methacryl". The thermosetting functional group-containing acrylic resin may be used alone or in combination of two or more.

Examples of the (meth) acrylic acid ester include hydrocarbon group-containing (meth) acrylic acid esters. Examples of the hydrocarbon group-containing (meth) acrylic acid ester include (meth) acrylic acid alkyl ester, (meth) acrylic acid cycloalkyl ester, and (meth) acrylic acid aryl ester. As the hydrocarbon group-containing (meth) acrylic acid ester, only one kind may be used, or two or more kinds may be used in combination. In the die bond film, in order to appropriately exhibit basic properties such as adhesiveness due to the hydrocarbon group-containing (meth) acrylic acid ester, the hydrocarbon group-containing (meth) in all the monomer components for forming the acrylic resin. ) The mass ratio of the acrylic acid ester is preferably 40% by mass or more, more preferably 60% by mass or more.

The heat-curable functional group-containing acrylic resin preferably contains an alkyl acrylate and a monomer containing, for example, a glycidyl group, a carboxy group, a hydroxy group, an isocyanate group, or the like as a heat-curable functional group as a constituent unit. Among these, the monomer containing a thermosetting functional group preferably contains a monomer containing a glycidyl group as a constituent unit.
Examples of the alkyl acrylate include ethyl acrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, and lauryl acrylate.
Examples of the monomer containing a glycidyl group include (meth) acrylic acid esters having a glycidyl group. Examples of the (meth) acrylic acid ester having a glycidyl group include glycidyl (meth) acrylate.
Examples of the monomer containing a carboxy group include acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid.
Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6-hydroxyhexyl (meth) acrylate. , (Meta) acrylate 8-hydroxyoctyl, (meth) acrylate 10-hydroxydecyl, (meth) acrylate 12-hydroxylauryl, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate and the like.
Examples of the monomer containing an isocyanate group include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate (MOI), m-isopropenyl-α, α-dimethylbenzoyl isocyanate and the like.
Further, as the thermosetting functional group-containing acrylic resin, a copolymer of ethyl acrylate, butyl acrylate, acrylonitrile, and glycidyl methacrylate is particularly preferable.
Further, when the thermosetting functional group-containing acrylic resin contains a monomer containing a glycidyl group as a constituent unit, the equivalent ratio of the hydroxyl group of the phenol resin to the glycidyl group is preferably 0 or more and 3.0 or less. It is more preferably 1.0 or more and 2.0 or less, and particularly preferably 1.2 or more and 1.7 or less.
Further, the copolymer preferably has a mass average molecular weight of 600,000 or more and 1,600,000 or less, more preferably 800,000 or more and 1,500,000 or less, and more preferably 1,000,000. It is particularly preferable that the amount is 1,400,000 or less. Further, the copolymer preferably has a glass transition temperature Tg of −5 ° C. or higher and 25 ° C. or lower, more preferably 0 ° C. or higher and 20 ° C. or lower, and further preferably 2 ° C. or higher and 18 ° C. or lower. preferable. The glass transition temperature Tg of the copolymer is particularly preferably 2 ° C. or higher and 6 ° C. or lower.
The mass average molecular weight is a value converted by standard polystyrene by the GPC method. As the GPC main body, HLC-8120 GPC manufactured by Tosoh Corporation was used, a column temperature of 40 ° C., a pump flow rate of 0.5 mL / min, and a detector RI were used. Data processing is performed on the calibration curve of standard polystyrene whose molecular weight is known in advance (molecular weight 20.6 million, 8.42 million, 4.48 million, 1.11 million, 707,000, 354,000, 189,000, 98,900, 3. A calibration curve can be obtained using standard polystyrenes of 720,000, 1710,000, 9830, 5870, 2500, 1050, and 500), and the molecular weight can be determined from the converted molecular weight. As the column, a column in which two TSKgel GMH-H (S) (manufactured by Tosoh Corporation) are connected in series is used, and tetrahydrofuran is used as the mobile phase, the injection amount is 100 μL, and the sample concentration is set. Can be 1.0 g / L (sample is dissolved in tetrahydrofuran).
Further, the glass transition temperature Tg means the intermediate point glass transition temperature in JIS K7121: 2012.

Examples of the thermosetting resin include epoxy resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, and thermosetting polyimide resin. The thermosetting resin may be used alone or in combination of two or more.
Among the above-mentioned various thermosetting resins, it is preferable to use an epoxy resin.

Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type and orthocresol. Examples thereof include novolak type, trishydroxyphenylmethane type, tetraphenylol ethane type, hydantin type, trisglycidyl isocyanurate type, and glycidylamine type epoxy resins.

The die bond film may contain a thermoplastic resin. The thermoplastic resin functions as a binder. Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, and polycarbonate resin. Examples thereof include thermoplastic polyimide resins, polyamide resins such as polyamide 6 and polyamides 6 and 6, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluororesins. That is, the acrylic resin may be contained as a thermoplastic resin. The thermoplastic resin may be used alone or in combination of two or more.
As the thermoplastic resin, an acrylic resin is preferable from the viewpoint that it is easy to secure the connection reliability by the die bond film because there are few ionic impurities and high heat resistance.

Examples of the acrylic resin as the thermoplastic resin include those containing a monomer unit derived from the (meth) acrylic acid ester as described above.
The acrylic resin as the thermoplastic resin can be used as another monomer component copolymerizable with the hydrocarbon group-containing (meth) acrylic acid ester in the die bond film from the viewpoint of achieving high cohesive force and high heat resistance. It may contain a constituent unit from which it is derived. Examples of the other monomer components include acid anhydride monomers, sulfonic acid group-containing monomers, phosphate group-containing monomers, and functional group-containing monomers such as acrylamide and acrylic nitrile. As the other monomer component, only one kind may be used, or two or more kinds may be used in combination.
In the die bond film, in order to appropriately exhibit properties such as adhesiveness due to the hydrocarbon group-containing (meth) acrylic acid ester, the mass ratio of the other monomer components to all the monomer components for forming the acrylic resin. Is preferably 60% by mass or less, and more preferably 40% by mass or less.

The phenolic resin is a curing agent for the thermosetting resin. Examples of such a phenol resin include a novolak type phenol resin, a resol type phenol resin, and polyoxystyrene such as polyparaoxystyrene. As the phenol resin, it is preferable to use a biphenyl aralkyl type phenol resin. As a commercially available product of the biphenyl aralkyl type phenol resin, the trade name "MEH-7851SS" manufactured by Meiwakasei Workers' Co., Ltd. can be mentioned.

The filler is contained in the die bond film in order to adjust physical properties such as conductivity, thermal conductivity, and elastic modulus of the die bond film.
As the filler, either an inorganic filler or an organic filler can be used, but it is preferable to use an inorganic filler.
Examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, titanium oxide, aluminum nitride, aluminum borate whisk, and the like. In addition to boron nitride and silica (crystalline silica, amorphous silica), simple metals such as aluminum, gold, silver, copper and nickel, alloys, amorphous carbon black, graphite and the like can be mentioned.
The filler may have various shapes such as a spherical shape, a needle shape, and a flake shape. The filler may be used alone or in combination of two or more.
Among the above-mentioned inorganic fillers, aluminum hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, aluminum oxide, titanium oxide, and silica ((2) silicon oxide) are preferably used, and silica is particularly preferable.

In the die bond film according to the present embodiment, the filler has a specific surface area of 5 m ² / g or more and 100 m ² / g or less. The specific surface area is preferably 5 m ² / g or more and 60 m ² / g or less, ^{more preferably 5 m 2} / g or more and 40 m ² / g or less, and 5 m ² / g or more and 25 m ² / g or less. Is even more preferable.
The specific surface area can be determined by a nitrogen adsorption method (JIS Z8830: 2010).

The average particle size of the filler is preferably 40 nm or more and 600 nm or less, more preferably 60 nm or more and 500 nm or less, and particularly preferably 180 nm or more and 500 nm or less. When the average particle size of the filler is within the numerical range, the specific surface area of the filler can ^{be easily adjusted to the above numerical range (5 m 2} / g or more and 100 m ² / g or less).
The average particle size of the filler can be measured by a dynamic light scattering method (DLS). Specifically, the filler is dispersed in methyl ethyl ketone (MEK) to prepare a particle size measurement sample so that the solid content concentration is 1% by mass or less, and the average particle size of the filler in the particle size measurement sample is prepared. Is measured with a dynamic light scattering photometer (model number "ZEN3600": manufactured by Sysmex).
The particle size measurement sample may be treated with an ultrasonic homogenizer for 2 minutes before the measurement.

The die-bonded film contains the acrylic resin, the phenol resin, and the filler, and further, the specific surface area of the filler is 5 m ² / g or more and 100 m ² / g or less, and the filler with respect to the acrylic resin. The present inventors speculate as follows about the reason why the residual voids can be relatively suppressed from the printed wiring board or the like by setting the content mass ratio to more than 0 and 1.50 or less. There is.

Generally, when the filler and the resin are uniformly mixed, parameters that contribute to polarity such as surface tension and SP value (solubility parameter) are appropriately adjusted to increase the affinity between the filler and the resin. There is a need. Then, when the affinity between the filler and the resin is increased, the resin is bound to the surface of the filler.
In particular, as the particle size of the filler becomes smaller, the number of atoms present on the surface of the filler in the number of all atoms constituting the filler becomes relatively large, so that the atoms present on the surface of the filler are relatively large. , The force acting between the atoms is smaller than that of the atoms existing inside the filler. When the number of atoms present on the surface of the filler is relatively large, the surface free energy of the filler is increased. In such a case, the filler becomes stable by reducing the surface free energy by adhering other substances to the surface.

Under such circumstances, if the particle size of the filler is reduced while the mass of the filler mixed with the resin is constant, the ratio of the value of the specific surface area of the filler to the value of the mass of the filler increases. As the amount increases, the amount of the resin constrained by the surface of the filler also increases. That is, it is considered that the filler also functions to pseudo-crosslink the acrylic resin in the die bond film.

As described above, when the acrylic resin is constrained by the filler in the die-bonded film, it is considered that the voids (hereinafter, also referred to as free volumes) generated between the acrylic resins in the die-bonded film are reduced. .. It is considered that the larger the portion of the acrylic resin in the state of being restrained by the filler, the smaller the free volume in the die bond film. Then, as the free volume in the die bond film decreases, when a void is generated between the printed wiring board or the like and the die bond film, the air and moisture contained in the void are moved into the die bond film. Will be difficult.
Such a problem occurs when the acrylic resin is a thermosetting resin, that is, when the acrylic resin is a thermosetting group-containing acrylic resin (thermosetting acrylic resin), the acrylic resin itself. In addition to the cross-linking of the above, pseudo-cross-linking by the filler is also formed, which is considered to be more remarkable.

However, although the die bond film according to the present embodiment contains the acrylic resin and the filler, the specific surface area of the filler ^{is relatively small, 100 m 2} / g or less, and therefore the filler is used. It is considered that the acrylic resin can be prevented from being excessively restrained. As a result, it is considered that the free volume in the die-bonded film can be relatively suppressed from being reduced to the extent that it becomes difficult to move the air and moisture contained in the void into the die-bonded film.
Further, the content mass ratio of the filler to the acrylic resin is larger than 0 and 1.50 or less, that is, the content mass of the acrylic resin is sufficiently larger than the content mass of the filler, so that the filler is contained. Even when it is considered that the acrylic resin is in a restrained state due to the above, it is considered that a sufficient free volume can be secured in the die bond film.
Thereby, when the semiconductor package is obtained, the air and moisture contained in the void can be sufficiently moved into the die bond film at the temperature at which the sealing resin is cured (for example, 175 ° C.). it is conceivable that. As a result, it is considered that voids can be relatively suppressed from remaining between the wiring board and the like and the die bond film.
Since the air and the moisture that have moved into the die bond film can be sufficiently released into the atmosphere while the sealing resin is being cured, they remain in the semiconductor package in the state of being in the semiconductor package. It can reduce the amount of water to be used. As a result, it is possible to suppress the occurrence of the so-called popcorn phenomenon in heating in a reflow oven when obtaining a semiconductor device.

In the die-bonded film according to the present embodiment, the lower limit of the surface area of the filler is 5 m ² / g, so that it is considered that the filler can have a size capable of suppressing surface exposure from the die-bonded film. ..

The die bond film may contain a thermosetting catalyst (curing accelerator) from the viewpoint of sufficiently advancing the curing reaction of the resin component and increasing the curing reaction rate. Examples of the thermosetting catalyst include imidazole-based compounds, triphenylphosphine-based compounds, amine-based compounds, and trihalogenborane-based compounds.

The die-bonded film may contain one or more other components, if necessary. Other components include, for example, flame retardants, silane coupling agents, and ion trapping agents.

The thickness of the die bond film is not particularly limited, but is, for example, 0.5 μm or more and 200 μm or less. Such a thickness may be 1 μm or more and 50 μm or less, or may be 2 μm or more and 30 μm or less.
The thickness of the die bond film is determined by measuring the thickness of any five randomly selected points using a dial gauge (manufactured by PEACOCK, model R-205) and arithmetically averaging these thicknesses. Can be done.

In the die-bonded film, the ratio of the thickness of the die-bonded film to the average particle size of the filler is preferably 5 or more and 150 or less.
It is considered that the surface exposure of the filler from the die bond film can be suppressed by the ratio of the thickness of the die bond film to the average particle size of the filler being 5 or more.
Further, when the ratio of the thickness of the die-bonded film to the average particle size of the filler is 150 or less, the filler contained in the die-bonded film has a relatively large average particle size. As a result, the filler contained in the die bond film has a relatively small specific surface area, so that it is possible to further suppress the excessive restraint of the acrylic resin by the filler. As a result, it is possible to further suppress the residual voids between the printed wiring board or the like and the die bond film.

In the die bond film, the water absorption rate is preferably 0.22% by mass or less, more preferably 0.19% by mass or less, and further preferably 0.12% by mass or less.
The water absorption rate can be measured by the Karl Fischer moisture vaporization-potentiometric titration method (JIS K 0113: 2005). Specifically, a 10 mg sample collected from the die bond film was used as a curl fisher moisture meter (manufactured by Mitsubishi Chemical Corporation, moisture vaporizer VA-07 type, trace moisture measuring device (coulometric titration method automatic moisture measuring device) CA- Using a type 07 and an automatic water content measuring device KF-07 type), measure the amount of water generated by heating and vaporizing at 150 ° C for 3 minutes, and calculate the ratio to the sample mass before heating as the water absorption rate. be able to.

Water absorption rate (% by mass) = (moisture content measured by curl fisher / total mass of sample before measurement) x 100

When the water absorption rate of the die bond film is 0.22% by mass or less, the amount of water vapor generated when heated to 100 ° C. or higher in the die bond film can be reduced. As a result, it is possible to further suppress the residual voids between the wiring board or the like and the die bond film.

In the die bond film, the ratio of the parallel line transmittance at a wavelength of 1000 nm to the value of the parallel line transmittance at a wavelength of 250 nm is preferably 2100 or more and 4500 or less, and more preferably 2500 or more and 3500 or less.
When the ratio of the value of the parallel line transmittance at the wavelength of 1000 nm to the value of the parallel line transmittance at a wavelength of 250 nm is within the above numerical range, it is further prevented that voids remain between the wiring substrate or the like and the die bond film. Can be suppressed.
As described above, when the ratio of the value of the parallel line transmittance at the wavelength of 1000 nm to the value of the parallel line transmittance at the wavelength of 250 nm is within the above numerical range, the die bond film (for example, the die bond attached to one surface of the semiconductor chip) is attached. Thermal history (curing reaction It is considered that it is possible to suppress the excessive progress of the curing reaction of the die-bonded film by the history of the amount of heat contributing to the progress, the history of the environmental temperature, etc.). For example, it is considered that a plurality of factors (such as the amount of a plurality of organic components (for example, phenol resin, acrylic resin, etc.)) that contribute to the curing reaction of the die bond film can be appropriately adjusted.
As a result, the free volume in the die-bonded film can be more sufficiently secured, and the air and moisture contained in the void can be more sufficiently moved in the die-bonded film. It is considered that the voids can be further suppressed from remaining between the die-bonded film and the die-bonded film.
The present inventors consider that the above reason is one of the reasons why the voids remaining between the wiring board and the like and the die bond film can be further suppressed.

In the die bond film, the value of the parallel line transmittance at a wavelength of 250 nm is preferably 0.01% or more and 0.05% or less, and more preferably 0.02% or more and 0.04% or less.
In the die bond film, the value of the parallel line transmittance at a wavelength of 1000 nm is preferably 60% or more and 100% or less, and more preferably 75% or more and 95% or less.
The parallel line transmittance at a wavelength of 250 nm and the parallel line transmittance at a wavelength of 1000 nm of the die bond film can be measured using a spectrophotometer (manufactured by JASCO Corporation, trade name “V-670”). The measurement wavelength can be in the range of 190 nm to 1400 nm. Further, the measurement sample can be prepared by preparing the die bond film so as to have a thickness of about 20 μm.

[Dicing die bond film]
As shown in FIG. 1, the dicing die bond film 20 according to the present embodiment is laminated on the dicing tape 10 in which the adhesive layer 2 is laminated on the base material layer 1 and on the adhesive layer 2 of the dicing tape 10. The die bond layer 3 is provided.
In the dicing die bond film 20 according to the present embodiment, the above-mentioned die bond film is used as the die bond layer 3.
In the dicing die bond film 20 according to the present embodiment, a semiconductor wafer is attached on the die bond layer 3.
In the cutting of the semiconductor wafer using the dicing die bond film 20, the die bond layer 3 is also cut together with the semiconductor wafer. The die bond layer 3 is divided into a size corresponding to the size of a plurality of semiconductor chips that have been fragmented. As a result, a semiconductor chip with the die bond layer 3 can be obtained.

The base material layer 1 supports the pressure-sensitive adhesive layer 2. The base material layer 1 is made by using a resin film. Resins contained in the resin film include polyolefin, polyester, polyurethane, polycarbonate, polyetheretherketone, polyimide, polyetherimide, polyamide, total aromatic polyamide, polyvinyl chloride, polyvinylidene chloride, polyphenylsulfide, and fluororesin. Examples thereof include a cellulose resin and a silicone resin.

As polyolefin, polyester, polyurethane, polycarbonate, polyether ether ketone, polyimide, polyetherimide, polyamide, total aromatic polyamide, polyvinyl chloride, polyvinylidene chloride, polyphenyl sulfide, fluororesin, cellulose resin, and silicone resin. Can be used with various known substances.

The pressure-sensitive adhesive layer 2 contains a pressure-sensitive adhesive. The pressure-sensitive adhesive layer 2 is held by adhering a semiconductor wafer for individualization to a semiconductor chip.

Examples of the adhesive include those capable of reducing the adhesive force by an action from the outside in the process of using the dicing tape 10 (hereinafter referred to as an adhesive reducing adhesive).

When an adhesive-reducing adhesive is used as the adhesive, the adhesive layer 2 exhibits a relatively high adhesive force (hereinafter referred to as a high adhesive state) and a relatively low adhesive force in the process of using the dicing tape 10. It is possible to use the state (hereinafter referred to as low adhesive state) properly. For example, when the semiconductor wafer attached to the dicing tape 10 is subjected to splitting, it is possible to prevent a plurality of semiconductor chips separated by the splitting of the semiconductor wafer from floating or peeling from the pressure-sensitive adhesive layer 2. Therefore, the high adhesive state is used. On the other hand, in order to pick up a plurality of fragmented semiconductor chips after the semiconductor wafer is cut, a low adhesive state is used in order to facilitate picking up a plurality of semiconductor chips from the pressure-sensitive adhesive layer 2.

Examples of the adhesive-reducing adhesive include an adhesive that can be cured by irradiation in the process of using the dicing tape 10 (hereinafter referred to as a radiation-curable adhesive).

Examples of the radiation-curing pressure-sensitive adhesive include a type of pressure-sensitive adhesive that cures by irradiation with an electron beam, ultraviolet rays, α-rays, β-rays, γ-rays, or X-rays. Among these, it is preferable to use a pressure-sensitive adhesive (ultraviolet-curing pressure-sensitive adhesive) that is cured by irradiation with ultraviolet rays.

The radiation-curable pressure-sensitive adhesive contains, for example, a base polymer as a main component and a radiation-polymerizable monomer component or a radiation-polymerizable oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond. Examples include mold radiation curable adhesives.
As the base polymer, it is preferable to use an acrylic polymer.

Examples of the acrylic polymer include those containing a monomer unit derived from a (meth) acrylic acid ester. Examples of the (meth) acrylic acid ester include (meth) acrylic acid alkyl ester, (meth) acrylic acid cycloalkyl ester, and (meth) acrylic acid aryl ester.
Examples of the acrylic polymer include 2-hydroxyethyl acrylate (HEA), ethyl acrylate (EA), butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), isononyl acrylate (INA), and lauryl acrylate (LA). , 4-Acryloylmorpholine (AMCO), 2-isocyanatoethyl-methacrylate (MOI) and the like are preferably used.
These acrylic polymers may be used alone or in combination of two or more.

The pressure-sensitive adhesive layer 2 may contain an external cross-linking agent. As the external cross-linking agent, any one that can react with a base polymer (for example, an acrylic polymer) to form a cross-linked structure can be used. Examples of such an external cross-linking agent include polyisocyanate compounds, epoxy compounds, polyol compounds, aziridine compounds, and melamine-based cross-linking agents.

Examples of the radiation-polymerizable monomer component include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol monohydroxypenta (meth). ) Acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate and the like. Examples of the radiation-polymerizable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based. The content ratio of the radiation-polymerizable monomer component and the radiation-polymerizable oligomer component in the radiation-curable pressure-sensitive adhesive is selected within a range that appropriately reduces the stickiness of the pressure-sensitive adhesive layer 2.

The radiation-curing pressure-sensitive adhesive preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include α-ketor compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanthone compounds, and camphor. Examples thereof include quinone, halogenated ketone, acylphosphinoxide, and acylphosphonate.

When the pressure-sensitive adhesive layer 2 contains an external cross-linking agent, the pressure-sensitive adhesive layer 2 preferably contains 0.1 part by mass or more and 3 parts by mass or less of the external cross-linking agent.
When the pressure-sensitive adhesive layer 2 contains a photopolymerization initiator, the pressure-sensitive adhesive layer 2 preferably contains 0.1 parts by mass or more and 10 parts by mass or less of the photopolymerization initiator.

The pressure-sensitive adhesive layer 2 may contain a cross-linking accelerator, a pressure-sensitive adhesive, an anti-aging agent, a pigment, a colorant such as a dye, or the like, in addition to the above-mentioned components.

The thickness of the pressure-sensitive adhesive layer 2 is preferably 1 μm or more and 50 μm or less, more preferably 2 μm or more and 30 μm or less, and further preferably 5 μm or more and 25 μm or less.
For the thickness of the pressure-sensitive adhesive layer 2, for example, a dial gauge (manufactured by PEACOCK, model R-205) is used to measure the thickness of any five randomly selected points, and these thicknesses are arithmetically averaged. It can be obtained by.

The dicing die bond film 20 according to the present embodiment is used, for example, as an auxiliary tool for manufacturing a semiconductor integrated circuit. Hereinafter, specific examples of using the dicing die bond film 20 will be described.
Hereinafter, an example using the dicing die bond film 20 in which the base material layer 1 is one layer will be described.

The methods for manufacturing semiconductor integrated circuits are a half-cut process in which a groove is formed in the semiconductor wafer so that the semiconductor wafer is processed into chips (dies) by a cutting process, and a semiconductor wafer after the half-cut process is ground to reduce the thickness. A back grind process, a mounting process in which one surface (the surface opposite to the circuit surface) of the semiconductor wafer after the back grind process is attached to the die bond layer 3 and the semiconductor wafer is fixed to the dicing tape 10, and a half-cut process. The expanding step of widening the distance between the semiconductor chips, the calf maintenance step of maintaining the distance between the semiconductor chips, and the state where the die bond layer 3 is attached by peeling between the die bond layer 3 and the pressure-sensitive adhesive layer 2. It has a pickup step of taking out a semiconductor chip (die) and a die bond step of adhering the semiconductor chip (die) to which the die bond layer 3 is attached to an adherend. When carrying out these steps, the dicing die bond film 20 of the present embodiment is used as a manufacturing auxiliary tool.

In the half-cut step, as shown in FIGS. 2A and 2B, a half-cut process for cutting a semiconductor wafer into small pieces (dies) is performed. Specifically, the wafer processing tape T is attached to the surface of the semiconductor wafer W opposite to the circuit surface (see FIG. 2A). Further, the dicing ring R is attached to the wafer processing tape T (see FIG. 2A). With the wafer processing tape T attached, a groove for division is formed (see FIG. 2B). In the backgrinding process, as shown in FIGS. 2C and 2D, the semiconductor wafer is ground to reduce its thickness. Specifically, while the backgrinding tape G is attached to the surface on which the groove is formed, the wafer processing tape T attached first is peeled off (see FIG. 2C). With the back grind tape G attached, grinding is performed until the semiconductor wafer W has a predetermined thickness (see FIG. 2D).

In the mounting step, as shown in FIGS. 3A to 3B, the dicing ring R is attached to the adhesive layer 2 of the dicing tape 10, and then the half-cut semiconductor wafer W is attached to the surface of the exposed die bond layer 3. (See FIG. 3A). Then, the back grind tape G is peeled off from the semiconductor wafer W (see FIG. 3B).

In the expanding step, as shown in FIGS. 4A to 4C, the dicing ring R is fixed to the holder H of the expanding device. The dicing die bond film 20 is stretched so as to spread in the plane direction by pushing up the dicing die bond film 20 from the lower side by using the push-up member U provided in the expanding device (see FIG. 4B). As a result, the semiconductor wafer W that has been half-cut is cut under a specific temperature condition. The above temperature conditions are, for example, -15 to 40 ° C, preferably -15 to 10 ° C, and more preferably -15 to 0 ° C. The expanded state is released by lowering the push-up member U (see FIG. 4C).
Further, in the expanding step, as shown in FIGS. 5A to 5B, higher temperature conditions (for example, 15 to 60 ° C., preferably 20 to 40 ° C., more preferably room temperature (23 ° C.)). ), The dicing tape 10 is stretched so as to increase the area. As a result, the cut adjacent semiconductor chips are separated from each other in the plane direction of the film surface, and the distance is further widened.

A series of steps from the half-cutting step to the expanding step may be referred to as a "DBG (Dicking Before Grinding) cutting process".
Further, in the half-cut step, a modified region forming step is performed so that the semiconductor wafer can be easily divided by the planned division line by irradiating the planned division line on the semiconductor wafer with a laser beam to form a modified region. Can also be replaced with. A series of steps from the modified region forming step to the expanding step may be referred to as "SDBG (Stealth Dicing Before Grinding) cutting process".

In the calf maintenance step, as shown in FIG. 6, hot air (the set value of the device for generating hot air is, for example, 200 to 250 ° C.) is applied to the dicing tape 10 to heat-shrink the dicing tape 10 and then cool and solidify the dicing tape 10. , Maintain the distance (calf) between the adjacent semiconductor chips that are cut.

In the pickup step, as shown in FIG. 7, the semiconductor chip to which the die bond layer 3 is attached (hereinafter, also referred to as a semiconductor chip with a die bond layer) is peeled from the adhesive layer 2 of the dicing tape 10. Specifically, the pin member P is raised to push up the semiconductor chip with a die bond layer to be picked up via the dicing tape 10. The pushed-up semiconductor chip with a die bond layer is held by the suction jig J.

In the die bond process, the semiconductor chip with the die bond layer is adhered to an adherend (wiring substrate).
In the dicing die bond film 20 according to the present embodiment, since the above-mentioned die bond film is used as the die bond layer 3, the semiconductor chip with the die bond layer is adhered to the wiring substrate, and the semiconductor chip with the die bond layer and the wiring substrate are adhered to the wiring substrate. Is electrically connected by wire bonding, and the temperature at which the sealing resin is cured after the semiconductor chip with the die bond layer bonded by the sealing resin and the wiring substrate are sealed (for example, 175). At ° C.), voids generated between the wiring substrate and the die bond layer 3 (die bond film) can be sufficiently removed. That is, it is possible to relatively suppress the residual voids between the wiring board and the die bond layer 3.
As a result, it is possible to obtain a semiconductor package in which voids are relatively suppressed from remaining between the wiring board and the die bond layer 3. Therefore, when obtaining a semiconductor device, the semiconductor package is electrically attached to the motherboard. In order to connect, it is possible to relatively suppress the occurrence of popcorn phenomenon in the semiconductor package when heating in a reflow furnace.

Further, the dicing die bond film 20 according to the present embodiment is used as a constituent member of the semiconductor package as described above.
In a specific example, a plurality of semiconductor chips, a wiring board having a mounting surface on which the semiconductor chips are mounted, a plurality of bonding films for adhering the semiconductor chips to the wiring board, and at least the mounting surface are covered. A sealing resin (molded resin) for sealing (molding) the wiring substrate is provided, and the first bonding film among the plurality of bonding films is bonded to the mounting surface, and the first bonding film is bonded to the mounting surface. The semiconductor chip and the remaining bonding film are alternately laminated on the bonding film 1 to form a laminated structure consisting of the plurality of bonding films and the plurality of semiconductor chips, and the laminated structure is the said. The dicing die bond film 20 according to the present embodiment is used as the bonding film of the semiconductor package embedded in the sealing resin.

When manufacturing a semiconductor package as described above, the laminated structure is formed of the laminated structure fixed to the mounting surface by the first bonding film, and the laminated structure is made of the sealing resin in a heat-melted state. The mounting surface is sealed so that the mounting surface is embedded.
Forming the laminated structure may include producing a laminated structure in which each bonding film has thermosetting property. Producing the laminated structure may include wire bonding the semiconductor chip and the wiring board. Producing the laminated structure may include performing thermal curing of the bonding film individually after the die attachment in the wire bonding.
The sealing may include causing a thermosetting reaction in the bonding film by the heat of the mold resin in a heat-melted state. In other words, in wire bonding, it is not necessary to individually heat-cure the bonding film after die attachment (die bonding). When the bonding film is not heat-cured individually, even if a void (gas) is generated between the bonding film and the wiring board in the sealing (molding), the void is formed. Disappears. The reason is as follows.
In the sealing, when the laminated structure is compressed under high temperature and high pressure (for example, 175 ° C., pressing pressure 8 MPa), voids (gas) are also compressed. Since the compressed gas having a smaller volume (that is, the gas having a smaller particle size) is mixed with the resin in a state where the contact area with the resin is increased, the free energy in the system including the laminated structure is increased. It will be stabilized. As a result of stabilizing the free energy in the system in this way, the voids can be sufficiently eliminated at the temperature at which the seal is applied. Further, in the portion where the void disappears, the resin and the surface of the wiring board and the resin and the surface of the semiconductor chip come into contact with each other, and the anchor effect is generated in this contact portion. The contact state between the resin and the surface of the wiring board and the contact state between the resin and the surface of the semiconductor chip are more sufficiently maintained.
As described above, the die bond film according to the present embodiment can relatively suppress the residual voids from the surface of the adherend (for example, the wiring board), and therefore, as described above, the wiring board is used as a laminated structure. Even if it is bonded to the above, it is possible to relatively suppress the residual voids between the surface of the die bond film and the surface of the wiring board, and between the surface of the die bond film and the surface of the semiconductor chip. ..

The dicing die bond film according to the present invention is not limited to the above embodiment. Further, the dicing die bond film according to the present invention is not limited by the above-mentioned action and effect. The dicing die bond film according to the present invention can be variously modified without departing from the gist of the present invention.

Next, the present invention will be described in more detail with reference to examples. The following examples are for the purpose of explaining the present invention in more detail, and do not limit the scope of the present invention.

[Example 1]
<Making a die bond film>
A copolymer of acrylic resin A (ethyl acrylate (EA), butyl acrylate (BA), acrylonitrile (AN) and glycidyl methacrylate (GMA) (mass average molecular weight is 1,200,000, glass transition temperature Tg is 4). Acrylic resin solution in which (° C.) was dissolved in methyl ethyl ketone (MEK)), phenol resin (trade name "MEH-7851ss", manufactured by Meiwa Kasei Co., Ltd.), and methyl ethyl ketone (MEK) were mixed to prepare a solution A1a. To the solution A1a, a solution A1b in which spherical silica (trade name "SO-E2", manufactured by Admatex Co., Ltd., average particle diameter 500 nm) is dispersed in methyl ethyl ketone is added and adhered so that the solid content concentration becomes 18% by mass. The agent composition A was prepared. In the adhesive composition A, the acrylic resin A, the phenol resin, and the spherical silica have the mass ratios shown in Table 1.
Next, the adhesive composition A is applied to the silicone release-treated surface of the PET separator (thickness 50 μm) having the silicone release-treated surface using an applicator to form a coating film, and the coating film is formed. The membrane was desolvated at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 7 μm (the die-bonded film according to Example 1) was produced on the PET separator.

The average particle size of spherical silica was measured by a dynamic light scattering method (DLS). Specifically, a sample for measuring the particle size is prepared by dispersing spherical silica in methyl ethyl ketone (MEK) so that the solid content concentration is 1% by mass or less, and the average particles of the spherical silica in the sample for measuring the particle size are prepared. The diameter was measured with a dynamic light scattering photometer (model number "ZEN3600": manufactured by Sysmex).
The particle size measurement sample was treated with an ultrasonic homogenizer for 2 minutes before the measurement.
Further, for the thickness of the die bond film according to Example 1, a dial gauge (manufactured by PEACOCK, model R-205) is used to measure the thickness of any five randomly selected points, and these thicknesses are arithmetically averaged. I asked for it.

[Example 2]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with methacrylic silane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (average particle size of spherical silica particles is 180 nm), acrylic resin A, phenol resin, and spherical silica were used in Table 1 below. The adhesive composition B was prepared in the same manner as in Example 1 except that it was prepared so as to have a mass ratio, and the adhesive composition B was prepared on the silicone release-treated surface of the PET separator using an applicator. Was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 5 μm (the die-bonded film according to Example 2) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 2 were measured by the same method as in Example 1.

[Example 3]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with vinylsilane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (average particle diameter of spherical silica particles is 180 nm), acrylic resin A, phenol resin, and spherical silica were added to the mass of Table 1 below. The adhesive composition C was prepared in the same manner as in Example 1 except that the ratio was adjusted, and the adhesive composition C was placed on the silicone release-treated surface of the PET separator using an applicator. It was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 9 μm (the die-bonded film according to Example 3) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 3 were measured by the same method as in Example 1.

[Example 4]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with an alkylsilane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (average particle size of spherical silica particles is 180 nm), acrylic resin A, phenol resin, and spherical silica were used in Table 1 below. The adhesive composition D was prepared in the same manner as in Example 1 except that it was prepared so as to have a mass ratio, and the adhesive composition D was prepared on the silicone release-treated surface of the PET separator using an applicator. Was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 7 μm (the die-bonded film according to Example 4) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 4 were measured by the same method as in Example 1.

[Example 5]
<Making a die bond film>
The adhesive composition E was prepared in the same manner as in Example 1 except that the acrylic resin A, the phenol resin, and the spherical silica were prepared so as to have the mass ratios shown in Table 1 below, and the PET separator was prepared. The adhesive composition E was applied onto the silicone release-treated surface using an applicator to form a coating film, and the coating film was desolvated at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 3 μm (the die-bonded film according to Example 5) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 5 were measured by the same method as in Example 1.

[Example 6]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with phenylsilane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (average particle size of spherical silica particles is 180 nm), acrylic resin A, phenol resin, and spherical silica were used in Table 1 below. The adhesive composition F was prepared in the same manner as in Example 1 except that the adhesive composition F was prepared so as to have a mass ratio, and the adhesive composition F was prepared on the silicone release-treated surface of the PET separator using an applicator. Was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 5 μm (the die-bonded film according to Example 6) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 6 were measured by the same method as in Example 1.

[Example 7]
<Making a die bond film>
The spherical silica is replaced with the trade name "MEK-EC-7150P (50%)" (average particle diameter 60 nm) manufactured by Nissan Chemical Co., Ltd., and the acrylic resin A, the phenol resin, and the spherical silica are replaced with the mass ratios in Table 1 below. The adhesive composition G was prepared in the same manner as in Example 1 except that the adhesive composition G was prepared, and the adhesive composition G was applied onto the silicone release-treated surface of the PET separator using an applicator. A coating film was formed, and the coating film was subjected to a desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 5 μm (the die-bonded film according to Example 7) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 7 were measured by the same method as in Example 1.

[Example 8]
<Making a die bond film>
The spherical silica is replaced with the trade name "MEK-AC-4130Y (30%)" (average particle diameter 50 nm) manufactured by Nissan Chemical Co., Ltd., and the acrylic resin A, the phenol resin, and the spherical silica are replaced with the mass ratios in Table 1 below. The adhesive composition H was prepared in the same manner as in Example 1 except that the adhesive composition H was prepared, and the adhesive composition H was applied onto the silicone release-treated surface of the PET separator using an applicator. A coating film was formed, and the coating film was subjected to a desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 5 μm (the die-bonded film according to Example 8) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 8 were measured by the same method as in Example 1.

[Example 9]
<Making a die bond film>
As the solution A1b, a silica particle dispersion solution obtained by dispersing the trade name "YA050C" manufactured by Admatex in methyl ethyl ketone (MEK), surface-treating with phenylsilane, and cutting coarse particles with a 1 μm filter. Adhesion was carried out in the same manner as in Example 1 except that the acrylic resin A, the phenol resin, and the spherical silica were prepared so as to have the mass ratios shown in Table 1 below. The agent composition I is prepared, and the adhesive composition I is applied onto the silicone release-treated surface of the PET separator using an applicator to form a coating film, and the coating film is formed at 130 ° C. for 2 minutes. Desolvent treatment was performed. As a result, a die-bonded film having a thickness (average thickness) of 3 μm (the die-bonded film according to Example 9) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 9 were measured by the same method as in Example 1.

[Example 10]
<Making a die bond film>
The spherical silica is replaced with the trade name "MEK-ST-L (30 wt%)" (average particle diameter 50 nm) manufactured by Nissan Chemical Co., Ltd., and the acrylic resin A, the phenol resin, and the spherical silica are replaced with the mass ratios in Table 1 below. The adhesive composition J was prepared in the same manner as in Example 1 except that the adhesive composition J was prepared, and the adhesive composition J was applied onto the silicone release-treated surface of the PET separator using an applicator. A coating film was formed, and the coating film was subjected to a desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 9 μm (the die-bonded film according to Example 10) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 10 were measured by the same method as in Example 1.

[Example 11]
Instead of the acrylic resin A, a copolymer of the acrylic resin B (ethyl acrylate (EA), butyl acrylate (BA), acrylonitrile (AN) and glycidyl methacrylate (GMA) (mass average molecular weight is 800,000, glass). Using an acrylic resin solution in which the transition temperature Tg is 15 ° C.) dissolved in methyl ethyl ketone (MEK), the product name "SO-C1" manufactured by Admatex Co., Ltd. and the product name "YC100C" manufactured by Admatex Co., Ltd. are used as the solution A1b. Was dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3, surface-treated with phenylsilane, and a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter was used (average particles of spherical silica particles). The adhesive composition X was adjusted in the same manner as in Example 1 except that the acrylic resin B, the phenol resin, and the spherical silica were prepared so as to have the mass ratios shown in Table 1 below. The adhesive composition X was applied onto the silicone release-treated surface of the PET separator using an applicator to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 9 μm (the die-bonded film according to Example 11) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 11 were measured by the same method as in Example 1.

[Example 12]
Instead of the acrylic resin A, a copolymer of the acrylic resin C (ethyl acrylate (EA), butyl acrylate (BA), acrylonitrile (AN) and glycidyl methacrylate (GMA) (mass average molecular weight is 600,000, glass). Using an acrylic resin solution in which the transition temperature Tg is 15 ° C.) dissolved in methyl ethyl ketone (MEK), the product name "SO-C1" manufactured by Admatex Co., Ltd. and the product name "YC100C" manufactured by Admatex Co., Ltd. are used as the solution A1b. Was dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3, surface-treated with phenylsilane, and a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter was used (average particles of spherical silica particles). The adhesive composition Y was adjusted in the same manner as in Example 1 except that the acrylic resin C, the phenol resin, and the spherical silica were prepared so as to have the mass ratios shown in Table 1 below. The adhesive composition Y was applied onto the silicone release-treated surface of the PET separator using an applicator to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 7 μm (the die-bonded film according to Example 12) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Example 12 were measured by the same method as in Example 1.

[Comparative Example 1]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with phenylsilane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (average particle size of spherical silica particles is 180 nm), acrylic resin A, phenol resin, and spherical silica were used in Table 1 below. The adhesive composition K was prepared in the same manner as in Example 1 except that the adhesive composition K was prepared so as to have a mass ratio, and the adhesive composition K was prepared on the silicone release-treated surface of the PET separator using an applicator. Was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 9.5 μm (the die-bonded film according to Comparative Example 1) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Comparative Example 1 were measured by the same method as in Example 1.

[Comparative Example 2]
<Making a die bond film>
The spherical silica is replaced with the trade name "MEK-EC-2130Y (30 wt%)" (average particle diameter 15 nm) manufactured by Nissan Chemical Co., Ltd., and the acrylic resin A, the phenol resin, and the spherical silica are replaced with the mass ratios in Table 1 below. The adhesive composition L was prepared in the same manner as in Example 1 except that it was added to the methyl ethyl ketone so as to be Was applied to form a coating film, and the coating film was subjected to desolvation treatment at 130 ° C. for 2 minutes. As a result, a die-bonded film having a thickness (average thickness) of 3 μm (the die-bonded film according to Comparative Example 2) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Comparative Example 2 were measured by the same method as in Example 1.

[Comparative Example 3]
<Making a die bond film>
As the solution A1b, the product name "SO-C1" manufactured by Admatex and the product name "YC100C" manufactured by Admatex are dispersed in methyl ethyl ketone (MEK) at a mass ratio of 2: 3 and surface-treated with phenylsilane. Using a silica particle dispersion solution obtained by cutting coarse particles with a 1 μm filter (the average particle size of spherical silica particles is 180 nm), acrylic resin A was used under the trade name “SG-70L” manufactured by Nagase Chemitex. The adhesive composition M was prepared in the same manner as in Example 1 except that the acrylic resin (SG-70L), the phenol resin, and the spherical silica were prepared so as to have the mass ratios shown in Table 1 below. After preparation, the adhesive composition M was applied onto the silicone release-treated surface of the PET separator using an applicator to form a coating film, and the coating film was desolvated at 130 ° C. for 2 minutes. rice field. As a result, a die-bonded film having a thickness (average thickness) of 5 μm (the die-bonded film according to Comparative Example 3) was produced on the PET separator.
The average particle size of the spherical silica and the thickness of the die bond film according to Comparative Example 3 were measured by the same method as in Example 1.

(Effect of post-mold cure (PMC) conditions on heat resistance)
The effect of post-mold cure conditions on heat resistance was evaluated for the die bond films according to each example. The effect of post-mold cure conditions on heat resistance was evaluated according to the following procedure.

(1) The die bond film according to each example is attached to a mirror chip having a plane size of 10 mm × 10 mm and a thickness of 50 μm at a temperature of 70 ° C., and then the PET separator is peeled off to prepare a mirror chip with a die bond film. Nine mirror chips with a die-bonded film are manufactured for each example.
(2) The mirror chips with 9 die-bonded films according to each example were placed in each section of a BGA (Ball Grid Array) substrate partitioned into 3 rows × 3 columns (divided into 9 sections) at a temperature of 120. Bonding is performed under the conditions of ° C., pressure 0.1 MPa, and 1 second.
(3) The BGA substrate is heated in a dryer at 150 ° C. for a predetermined time (0h, 2h, 4h, 6h) to post-mold cure.
(4) Using a molding machine (manual press Y-1 manufactured by TOWA Press) and a sealing resin, the BGA substrate is sealed under the conditions of a molding temperature of 175 ° C., a clamp pressure of 184 kN, a transfer pressure of 5 kN, and 120 seconds. Perform processing.
(5) After the sealing treatment, the sealing resin is heat-cured at 175 ° C. for 5 hours.
(6) Using an ultrasonic microscope (manufactured by HITACHI, model FS200II), an electric signal having a constant frequency of 50 MHz is shaped into a pulse shape for nine mirror chips with a die-bonded film bonded to the BGA substrate in a reflection mode. Then, by converting the pulsed electric signal into ultrasonic waves and irradiating the BGA substrate, it is observed whether or not peeling occurs between the surface of the BGA substrate and the surface of the die bond film. If even one of the nine mirror chips with a die bond film has peeling between the surface of the BGA substrate and the surface of the die bond film, it is evaluated as x because the heat resistance is insufficient. If there is no peeling in all of them, it is evaluated as 〇 as having sufficient heat resistance.
The state in which the peeling occurs between the surface of the BGA substrate and the surface of the die bond film is due to the fact that there are many voids generated between the surface of the BGA substrate and the surface of the die bond film. Conceivable.

The results of evaluating the effect of post-mold cure conditions on heat resistance are shown in Table 1 below.

(Effect of reflow temperature on heat resistance)
For the die bond film according to each example, the influence of the reflow temperature on the heat resistance was evaluated. The effect of reflow temperature on heat resistance was evaluated according to the following procedure.

(1) For the die bond film according to each example, the procedures (1) to (5) for evaluating the influence of the post-mold cure conditions on the heat resistance are performed.
(2) The BGA substrate according to each example after curing the sealing resin is exposed to a high temperature / high humidity environment (temperature 85 ° C., humidity 85% RH) for 168 hours. That is, the BGA substrate according to each example after the sealing resin is cured is exposed to an environment in which voids are more likely to occur between the surface of the BGA substrate and the surface of the die bond film.
(3) The BGA substrate according to each example after being exposed to a high temperature / high humidity environment is treated in an IR reflow oven at a temperature of 260 ° C. for 10 seconds.
(4) With respect to the nine mirror chips with die-bonded films bonded to the BGA substrate, an electric signal having a constant frequency of 50 MHz is shaped into a pulse shape in a reflection mode using an ultrasonic microscope (manufactured by HITACHI, model FS200II). Then, by converting the pulsed electric signal into ultrasonic waves and irradiating the BGA substrate, it is observed whether or not peeling occurs between the surface of the BGA substrate and the surface of the die bond film. If even one of the nine mirror chips with a die bond film has peeling between the surface of the BGA substrate and the surface of the die bond film, it is evaluated as x because the heat resistance is insufficient. If there is no peeling in all of them, it is evaluated as 〇, which is considered to have sufficient heat resistance.
The state in which the peeling occurs between the surface of the BGA substrate and the surface of the die bond film is due to the fact that there are many voids generated between the surface of the BGA substrate and the surface of the die bond film. Conceivable.

The results of evaluating the effect of reflow temperature on heat resistance are shown in Table 1 below.

(Parallel line transmittance)
For the die bond film according to each example, the parallel line transmittance at a wavelength of 250 nm and the parallel line transmittance at a wavelength of 1000 nm were measured using a spectrophotometer (manufactured by JASCO Corporation, trade name “V-670”).
The parallel line transmittance was measured in the measurement wavelength range of 190 nm to 1400 nm.
Further, as the measurement sample, the die bond film according to each example was laminated so as to have a thickness of about 20 μm.
The measurement results of the parallel line transmittance at a wavelength of 250 nm and the parallel line transmittance at a wavelength of 1000 nm, and the ratio of the parallel line transmittance at a wavelength of 1000 nm to the parallel line transmittance at a wavelength of 250 nm are shown in Table 1 below.

(Water absorption rate)
The water absorption rate of the die bond film according to each example was measured by the Karl Fischer moisture vaporization-potentiometric titration method (JIS K 0113: 2005).
Specifically, a 10 mg sample collected from the die bond film according to each example was used as a curl fisher moisture meter (manufactured by Mitsubishi Chemical Corporation, moisture vaporizer VA-07 type) as a trace moisture measuring device (coulometric titration method automatic moisture measuring device). ) Using CA-07 type and automatic moisture measuring device KF-07 type), measure the amount of moisture generated by heating vaporization at 150 ° C for 3 minutes, and measure the ratio to the sample mass before heating. Calculated as.

Water absorption rate (% by mass) = (moisture content measured by curl fisher / total mass of sample before measurement) x 100

The measurement results of the water absorption rate are shown in Table 1 below.

(Elastic modulus)
For the die bond film according to each example, the tensile storage elastic modulus at 150 ° C. was measured using a solid viscoelasticity measuring device (model RSA-G2, manufactured by Leometric Scientific).
Specifically, the die bond films according to each example are laminated to a thickness of 200 μm to obtain a laminated body, and a strip-shaped test piece having a length of 50 mm (measured length) × a width of 10 mm is obtained from the laminated body. With the solid viscoelasticity measuring device, the temperature range is 0 to 200 ° C. under the conditions of a frequency of 1 Hz, a strain amount of 0.1%, a heating rate of 10 ° C./min, and a chuck distance of 22.5 mm. The tensile storage elastic modulus of the test piece was measured.
At that time, the tensile storage elastic modulus at 150 ° C. was determined by reading the value at 150 ° C.
The measurement results of the tensile storage elastic modulus at 150 ° C. are shown in Table 1 below.

(Effect of post-mold cure (PMC) conditions on heat resistance)
From Table 1, it can be seen that the evaluation results by the ultrasonic microscope are 0 in all the cases when the post-mold cure is not performed (when the post-mold cure conditions are 150 ° C. for 0 hours).
This is because the acrylic resin having a thermosetting functional group was not sufficiently crosslinked in the die-bonded film because it was not post-molded, so that a sufficient free volume could be secured in the die-bonded film. It is thought that this is due to.
Further, from Table 1, when the post-mold cure condition was 150 ° C. for 2 hours, the evaluation result by the ultrasonic microscope was × in Comparative Example 2, but 〇 in all other examples. I understand.
The reason why the evaluation was x only in the case of Comparative Example 2 is that the filler contained in the die bond film according to Comparative Example 2 had an ^{extremely large specific surface area of 182 m 2} / g, so that the acrylic resin was restrained by the filler. In addition to the fact that the degree of cross-linking progresses in the die-bonded film, it is considered that the cause is that a sufficient free volume cannot be secured in the die-bonded film.
Further, from Table 1, in Examples 1 to 11, even when the post-mold cure condition was set to 150 ° C. for 6 hours, the evaluation results by the ultrasonic microscope were all 〇 (there was no problem in heat resistance). In Example 12, when the condition of post-mold cure was set to 150 ° C. for 4 hours, the evaluation result by the ultrasonic microscope was ◯ (there was no problem in heat resistance), whereas Comparative Example 1 In 1 and 3, even when the post-mold cure condition was set to 150 ° C. for 4 hours, the evaluation result by the ultrasonic microscope was × (there was a problem in heat resistance), and in Comparative Example 2, the post-mold cure was performed. It can be seen that in all cases where the condition of is set to 150 ° C. for 2 hours or more, it is x (there is a problem in heat resistance).
(Effect of reflow temperature on heat resistance)
From Table 1, it can be seen that the evaluation results by the ultrasonic microscope are 0 in all the examples when the reflow is performed at 260 ° C. without post-mold curing.
This can be considered to be due to the same reason as described above.
On the other hand, in Examples 1 to 11, the evaluation results by the ultrasonic microscope were all 0 (there was no problem in heat resistance) even when post-mold curing was performed at 150 ° C. for 6 hours and then reflowed at 260 ° C. In Example 12, after post-mold curing at 150 ° C. for 4 hours and then reflowing at 260 ° C., the evaluation result by the ultrasonic microscope was ◯ (there was no problem in heat resistance). The evaluation results of Comparative Examples 1 to 3 by an ultrasonic microscope show that they are all x (there is a problem in heat resistance) when they are post-molded at 150 ° C. for 4 hours and then reflowed at 260 ° C.
From the above results, an acrylic resin, a phenol resin, and a filler are contained, the specific surface area of the filler is 5 m ² / g or more and 100 m ² / g or less, and the mass ratio of the filler to the acrylic resin is larger than 0. By setting it to 1.50 or less, even if post-mold cure is performed for a relatively long time or reflow is performed at a temperature of 260 ° C., the die bond film is less likely to peel off from the printed wiring board, etc., and is heat resistant. It can be seen that the properties can be made high, that is, the voids can be made relatively unlikely to remain between the surface of the printed wiring board and the like.
The reason why the evaluation result by the ultrasonic microscope was 〇 under the condition of 150 ° C. × 0h in Table 1 was that the spherical silica as a filler was not exposed from the surface of the die bond film (the surface was exposed). It is presumed that it was not).
Here, the surface exposure in the present specification refers to the case where a semiconductor chip with a bonding film is laminated on a wiring substrate or the like by die attachment, or a laminated structure consisting of a plurality of bonding films and a plurality of semiconductor chips. When the body is manufactured, the particle size of the coarse filler is larger than the thickness of the bonding film, so that the surface of the coarse filler is exposed from the surface of the bonding film, which means that voids are generated. is doing.
The voids generated in this way can be confirmed by observing with an ultrasonic microscope. Furthermore, it is also possible to confirm the surface exposure of a coarse filler having a particle size larger than the thickness of the film by confirming the location where the void is generated by observing the cross section using SEM.

1 Base material layer 2 Adhesive layer 3 Dicing layer 10 Dicing tape 20 Dicing die bond film G Back grind tape H Holder J Adsorption jig P pin member R Dicing ring T Wafer processing tape U Push-up member W Semiconductor wafer

Claims (5)

A die bond film containing an acrylic resin, a phenol resin, and a filler.
The filler has a specific surface area of 5 m ² / g or more and 100 m ² / g or less.
A die bond film in which the content mass ratio of the filler to the acrylic resin is greater than 0 and 1.50 or less. The die bond film according to claim 1, wherein the water absorption rate is 0.22% by mass or less. The die bond film according to claim 1 or 2, wherein the ratio of the value of the parallel line transmittance at a wavelength of 1000 nm to the value of the parallel line transmittance at a wavelength of 250 nm is 2100 or more and 4500 or less. The die-bonded film according to any one of claims 1 to 3, wherein the ratio of the thickness of the die-bonded film to the average particle size of the filler is 5 or more and 150 or less. A dicing tape in which an adhesive layer is laminated on a base material layer,
A dicing layer laminated on the pressure-sensitive adhesive layer of the dicing tape is provided.
A dicing die bond film in which the die bond layer is the die bond film according to any one of claims 1 to 4.

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