KR20230011233A - Thermosetting resin sheet and dicing die bonding film - Google Patents

Abstract

The present invention provides a thermosetting resin sheet, and a dicing die bonding film including the thermosetting resin sheet. The thermosetting resin sheet contains a crosslinkable acrylic polymer having a crosslinkable group, which causes a crosslinking reaction by a thermosetting process, in a molecule thereof; has a shear loss modulus G' at 140 ℃ before the thermosetting process of 1 kPa or more and 20 kPa or less; and has a tensile elastic modulus at 150 ℃ after the thermosetting process at 150 ℃ for 1 hour of 0.5 MPa or more and 7.0 MPa or less.

Description

Thermosetting resin sheet and dicing die-bonding film {THERMOSETTING RESIN SHEET AND DICING DIE BONDING FILM}

The present invention relates to, for example, a dicing die-bonding film used when manufacturing a semiconductor device, and a thermosetting resin sheet provided in the dicing die-bonding film.

Conventionally, dicing die-bonding films used in the manufacture of semiconductor devices are known. This type of dicing die-bonding film includes, for example, a dicing tape and a die-bonding sheet laminated on the dicing tape and bonded to a wafer. The die-bonding sheet is composed of a thermosetting resin sheet. The dicing tape has a substrate layer and an adhesive layer in contact with the die-bonding sheet. This type of dicing die-bonding film is used in the manufacture of semiconductor devices, for example, as follows.

A method of manufacturing a semiconductor device generally includes a pre-process of forming a circuit surface on one side of a wafer with highly integrated electronic circuits, and a post-process of cutting out chips from the wafer on which the circuit surface is formed and assembling them.

The post-process includes, for example, a dicing step of forming a weak portion on the wafer for cutting the wafer into small chips (dies), and attaching the surface opposite to the circuit face of the wafer to a die-bonding sheet and attaching it to a dicing tape A mount process to fix the wafer, an expand process to widen the gap between the chips by splitting the wafer with a weak portion together with the die-bonding sheet, and a state in which the die-bonding sheet is attached by separating the die-bonding sheet and the adhesive layer. A pick-up step of taking out the chip (die), a die-bonding step of bonding the chip (die) with the die-bonding sheet attached to an adherend via the die-bonding sheet, and a heat-curing treatment of the die-bonding sheet adhered to the adherend It has a curing process that A semiconductor device is manufactured through these processes, for example.

In the method for manufacturing a semiconductor device as described above, for example, in the pick-up step, a die-bonding sheet containing an epoxy resin to improve peelability when peeling the die-bonding sheet together with a chip; A dicing die-bonding film provided with an adhesive layer in which a specific component is blended is known (for example, Patent Document 1).

In detail, in the dicing die-bonding film described in Patent Literature 1, the adhesive layer of the dicing tape contains an acrylic acid ester as a main monomer and a hydroxyl group-containing monomer in a content in the range of 10 to 30 mol% relative to the acrylic acid ester and an isocyanate compound having a radical reactive carbon-carbon double bond in a content of 70 to 90 mol% relative to the hydroxyl group-containing monomer, and the die-bonding film includes an epoxy resin.

According to the dicing die-bonding film described in Patent Literature 1, the die-bonding film can be easily peeled off from the adhesive layer cured by ultraviolet irradiation, and chips can be picked up satisfactorily together with the die-bonding film.

Japanese Unexamined Patent Publication No. 2009-135377

However, for example, in the above die-bonding process, when a chip is adhered to an adherend through a die-bonding sheet, there are cases where the surface of the adherend has irregularities. Therefore, it is necessary to cover the surface of the adherend with the die-bonding sheet so that the die-bonding sheet is deformed so as to follow the unevenness to embed the concave portion and no gap is formed.

In addition, for example, in the curing process described above, there is a case where warpage occurs in the die-bonding sheet due to the thermal curing treatment, and the chip is bent. This is considered to be due to the fact that the linear expansion coefficients of the chip, the die-bonding sheet (thermosetting resin sheet), and the adherend are different from each other. In particular, when the thickness of the adherend is relatively thin, the chip is easily bent.

In order to prevent such a problem, it is conceivable to design the die-bonding sheet so as to follow the irregularities on the surface of the adherend during die-bonding and to have good embedding properties and to reduce warping due to thermal curing.

However, dicing provided with a thermosetting resin sheet for a die-bonding sheet having good embedding properties during die-bonding and suppressing warpage accompanying the thermal curing treatment and the thermosetting resin sheet (die-bonding sheet) It cannot be said that the die-bonding film has been sufficiently studied yet.

Therefore, the present invention provides a thermosetting resin sheet for a die-bonding sheet having good embedding properties at the time of die-bonding and suppressing warpage associated with thermal curing treatment, and a dicing die-bonding provided with the thermosetting resin sheet We make it a subject to provide a film.

In order to solve the above problems, the thermosetting resin sheet according to the present invention,

In a method for manufacturing a semiconductor device, a thermosetting resin sheet used as a die-bonding sheet for bonding a chip to an adherend by placing a wafer having a circuit surface formed thereon between a chip and an adherend, comprising the steps of:

A crosslinkable acrylic polymer having a crosslinkable group in its molecule that causes a crosslinking reaction by heat curing treatment,

The shear loss modulus G" at 140°C before the thermal curing treatment is 1 kPa or more and 20 kPa or less, and the tensile modulus at 150°C after the thermal curing treatment at 150°C for 1 hour is 0.5 MPa or more and 7.0 MPa or less. to be characterized

The dicing die-bonding film according to the present invention includes the above thermosetting resin sheet and a dicing tape bonded to the thermosetting resin sheet.

1 is a cross-sectional view of a dicing die-bonding film of the present embodiment cut in the thickness direction.
Fig. 2A is a cross-sectional view schematically showing an aspect of a stealth dicing step in a method for manufacturing a semiconductor device.
2B is a cross-sectional view schematically showing an aspect of a stealth dicing step in a method for manufacturing a semiconductor device.
2C is a cross-sectional view schematically showing an aspect of a stealth dicing step in a method for manufacturing a semiconductor device.
Fig. 2D is a cross-sectional view schematically showing an aspect of a back-grind step in a method of manufacturing a semiconductor device.
3A is a cross-sectional view schematically showing an aspect of a mount step in a method of manufacturing a semiconductor device.
3B is a cross-sectional view schematically showing an aspect of a mount step in a method of manufacturing a semiconductor device.
Fig. 4A is a cross-sectional view schematically showing an aspect of an expand step at a low temperature in a method for manufacturing a semiconductor device.
Fig. 4B is a cross-sectional view schematically showing an aspect of an expand step at a low temperature in a method for manufacturing a semiconductor device.
4C is a cross-sectional view schematically showing an aspect of an expand step at a low temperature in a method of manufacturing a semiconductor device.
Fig. 5A is a cross-sectional view schematically showing an aspect of an expand step at room temperature in a method for manufacturing a semiconductor device.
Fig. 5B is a cross-sectional view schematically showing an aspect of an expand step at room temperature in a method for manufacturing a semiconductor device.
6 is a cross-sectional view schematically showing an aspect of a pick-up step in a method of manufacturing a semiconductor device.
Fig. 7 is a cross-sectional view schematically showing an aspect of a die bonding process in a method of manufacturing a semiconductor device.
Fig. 8 is a schematic diagram showing an example of a state of voids that may occur when a die-bonding sheet is adhered to an adherend.
Fig. 9 is a cross-sectional view schematically showing an aspect of a wire bonding step in a method of manufacturing a semiconductor device.
Fig. 10 is a cross-sectional view schematically showing an aspect of a sealing step in a method for manufacturing a semiconductor device.
Fig. 11 is a schematic cross-sectional view showing an example of a bent state of a semiconductor chip and a die-bonding sheet.

Hereinafter, one embodiment of the thermosetting resin sheet (die-bonding sheet) and the dicing die-bonding film provided with the thermosetting resin sheet (die-bonding sheet) according to the present invention will be described with reference to the drawings.

As shown in FIG. 1 , the dicing die-bonding film 1 of the present embodiment is laminated on a dicing tape 20 and an adhesive layer 22 of the dicing tape 20, and also on a semiconductor wafer. A thermosetting resin sheet (die-bonding sheet 10) to be bonded is provided. The thermosetting resin sheet (die-bonding sheet 10) is bonded to an adherend such as a circuit board or a semiconductor chip in the manufacture of a semiconductor device.

In addition, the figure in the drawing is a schematic diagram, and is not necessarily the same as the vertical and horizontal length ratio in the real thing.

In this embodiment, a thermosetting resin sheet is used for the die-bonding sheet 10 of the dicing die-bonding film 1. Therefore, the detailed description of the thermosetting resin sheet will be given by the description of the die-bonding sheet 10 hereinafter.

<Die-bonding sheet (thermosetting resin sheet) of dicing die-bonding film>

The die-bonding sheet 10 includes a crosslinkable acrylic polymer having a crosslinkable group in its molecule that causes a crosslinking reaction by heat curing treatment.

Further, the shear loss modulus G" of the die-bonding sheet 10 is 1 kPa or more and 20 kPa or less under the temperature condition of 140°C before the thermal curing treatment, and the tensile modulus of elasticity of the die-bonding sheet 10 is 1 at 150°C. It is 0.5 MPa or more and 7.0 MPa or less on the temperature condition of 150 degreeC after the heat curing process of time.

According to the die-bonding sheet 10 having the above structure, since the shear loss modulus G" at 140°C before the thermal curing treatment is 1 kPa or more and 20 kPa or less, it follows the irregularities on the surface of the adherend at the time of die bonding and provides good embedding. In addition, since the tensile modulus at 150°C after the thermal curing treatment at 150°C for 1 hour is 0.5 MPa or more and 7.0 MPa or less, the die-bonding sheet 10 generated by the thermal curing treatment It is possible to suppress the bending of the die-bonding sheet 10 due to internal stress. In addition, since the die-bonding sheet 10 contains a crosslinkable acrylic polymer having a relatively low elastic modulus as a crosslinkable polymer, the die after curing The bond sheet 10 has an appropriately low modulus of elasticity and can have flexibility, so that the above-mentioned internal stress of the die-bonding sheet 10 is relieved, and the die-bonding sheet ( 10) can be suppressed.

Thus, according to the thermosetting resin sheet (die-bonding sheet 10) of the present embodiment and the dicing die-bonding film 1 provided with the thermosetting resin sheet, good embedding properties can be exhibited during die bonding. In addition, the curvature accompanying the thermosetting treatment is suppressed.

The above crosslinkable acrylic polymer is a high molecular compound in which at least a (meth)acrylic acid ester monomer is polymerized.

In addition, in this specification, the notation "(meth)acrylic acid" shows at least one of methacrylic acid and acrylic acid, and the notation "(meth)acrylate" means methacrylate (methacrylic acid ester) and acrylate (Acrylic acid ester) at least one is shown. The term "(meth)acryl" is also the same.

The above crosslinkable acrylic polymer usually has the above crosslinkable group in its side chain. Said crosslinkable acrylic polymer may have said crosslinkable group at the terminal of a side chain. Moreover, said crosslinkable acrylic polymer may have said crosslinkable group at least one of both ends of a principal chain.

The crosslinkable group in the molecule of the above crosslinkable acrylic polymer is not particularly limited as long as it is a functional group that causes a crosslinking reaction by thermal curing.

As a crosslinkable group, the low activity crosslinkable group which has an active hydrogen, or the highly active crosslinkable group which can react with an active hydrogen is mentioned, for example.

As a low-activity crosslinkable group, a hydroxyl group or a carboxy group etc. are mentioned, for example. These crosslinkable groups can cause a crosslinking reaction with an epoxy group or an isocyanate group. For example, the crosslinkable acrylic polymer having at least one of a hydroxyl group or a carboxy group in its molecule can cause a crosslinking reaction between compounds having an epoxy group or an isocyanate group in its molecule (for example, an epoxy resin described later).

As a highly active crosslinkable group, an epoxy group or an isocyanate group etc. are mentioned, for example. These crosslinkable groups can cause a crosslinking reaction with a hydroxy group or a carboxy group. For example, the above crosslinkable acrylic polymer having at least one of an epoxy group or an isocyanate group in its molecule undergoes a crosslinking reaction between a compound having at least one of a hydroxyl group or a carboxy group in its molecule (for example, a phenol resin described later) can cause

The content ratio of the structural unit of the crosslinkable group-containing monomer in the above crosslinkable acrylic polymer may be 0.5% by mass or more and 50.0% by mass or less, or 1% by mass or more and 40% by mass or less.

When the above ratio is 0.5% by mass or more, the crosslinking reaction at the time of thermal curing of the die-bonding sheet 10 can be more sufficiently advanced. On the other hand, when the above ratio is 50.0% by mass or less, the elastic modulus of the die-bonding sheet 10 after the thermal curing treatment is lowered, so that the warpage of the die-bonding sheet 10 accompanying the thermal curing treatment can be further suppressed.

When the above crosslinkable acrylic polymer has a hydroxyl group or a carboxyl group as a crosslinkable group in the molecule, the proportion of structural units containing a crosslinkable group in the crosslinkable acrylic polymer may be 1% by mass or more and 50% by mass or less.

When the above crosslinkable acrylic polymer has an epoxy group as a crosslinkable group in the molecule, the proportion of structural units containing an epoxy group in the crosslinkable acrylic polymer may be 5% by mass or more and 50% by mass or less, and may be 7% by mass or more 40 It may be less than mass %.

In addition, a structural unit is a structure derived from each monomer after polymerization of monomers (for example, 2-ethylhexyl acrylate, hydroxyethyl acrylate, etc.) at the time of obtaining a crosslinkable acrylic polymer. Same below.

When the above crosslinkable acrylic polymer has an epoxy group as a crosslinkable group in the molecule, the epoxy equivalent of the crosslinkable acrylic polymer may be 1,300 [g/eq] or more and 4,200 [g/eq] or less, or 1,500 [g/eq] or more. It may be 2,500 [g/eq] or less.

When the epoxy equivalent of the crosslinkable acrylic polymer is 1,300 [g/eq] or more, the die-bonding sheet 10 after heat curing can have better heat resistance. In addition, when the epoxy equivalent of the crosslinkable acrylic polymer is 4,200 [g/eq] or less, warpage of the die-bonding sheet 10 accompanying the thermal curing treatment can be further suppressed.

The epoxy equivalent of the above crosslinkable acrylic polymer is measured by a method according to JIS K7236: 2001 (indicator titration method/potentiometric titration method).

The die-bonding sheet 10 of this embodiment may contain one or more crosslinkable acrylic polymers.

At least two types of crosslinkable acrylic polymers of multiple types crosslink each other. That is, the crosslinkable group of one crosslinkable acrylic polymer and the crosslinkable group of the other crosslinkable acrylic polymer can crosslink each other.

Crosslinkable acrylic polymers of different types each have, for example, crosslinkable groups in their molecules that crosslink with each other. Specifically, a crosslinkable acrylic polymer having at least one of a hydroxyl group or a carboxy group in the molecule as a crosslinkable group and a crosslinkable acrylic polymer having at least one of an epoxy group or an isocyanate group in the molecule as a crosslinkable group are of different types.

Alternatively, crosslinkable acrylic polymers of different types have different types of structural units of monomers in the molecule, for example. Specifically, a crosslinkable acrylic polymer having a hydroxyl group-containing (meth)acrylic monomer and an alkyl (meth)acrylate monomer as structural units in a molecule, and a carboxyl group-containing (meth)acrylic monomer and an alkyl (meth)acrylate monomer as structural units As for the crosslinkable acrylic polymers in the molecule, there are different types.

The mass average molecular weight of at least one of the crosslinkable acrylic polymers may be 10,000 or more and 400,000 or less. The mass average molecular weight of the at least one crosslinkable acrylic polymer may be 20,000 or more and 350,000 or less, or 30,000 or more and 300,000 or less. The value of this mass average molecular weight is the value when GPC measurement of a crosslinkable acrylic polymer is carried out.

When the mass average molecular weight of the crosslinkable acrylic polymer is 10,000 or more, there is an advantage that the sheet shape of the die-bonding sheet 10 is more easily maintained. In addition, when the crosslinkable acrylic polymer has a mass average molecular weight of 400,000 or less, the die-bonding sheet 10 can exhibit better embedding properties.

The above mass average molecular weight is measured by gel permeation chromatography (GPC). Measurement conditions are as follows.

Assume device name (device example): product name "1200" manufactured by Agilent

Detector: Differential refractive index (RI) detector

Column: 3 columns connected in series

Tosoh Corporation product name "TSKgel SuperAWM-H/superAW4000/superAW2500" (column diameter = 6 mm, column length = 15 cm)

Column temperature: 40°C

Flow rate: 0.4mL/min

Injection amount: 40 μL (eluent preparation solution with a sample concentration of 0.1% by mass)

Standard material for calibration curve construction: polystyrene

Data processing software: Waters company product name "Empower3"

Eluent: Tetrahydrofuran (DMF) salt added

Measurement of number average molecular weight (Mn), mass average molecular weight (Mw), molecular weight distribution (Mw/Mn), etc.

The above crosslinkable acrylic polymer can be synthesized by a general polymerization method using a radical polymerization initiator, for example.

As described above, the die-bonding sheet 10 of the present embodiment has a shear loss modulus G" at 140°C before the thermal curing treatment of 1 kPa or more and 20 kPa or less.

This shear loss modulus G" may be 1.2 kPa or more, and may be 2.1 kPa or more. In addition, such shear loss elasticity modulus G" may be 19.0 kPa or less, and may be 18.0 kPa or less.

When the shear loss modulus G" is 1 kPa or more and 20 kPa or less, as described above, the die-bonding sheet 10 can exhibit good embedding property (irregularity followability on the surface of an adherend) during die bonding.

The shear loss modulus G" of the die-bonding sheet 10 before thermal curing can be increased by, for example, increasing the molecular weight of the crosslinkable acrylic polymer. On the other hand, the molecular weight of the crosslinkable acrylic polymer By making it smaller, the shear loss elastic modulus G" can be lowered.

The shear loss modulus G" described above is measured under the following measurement conditions. Details of the measurement method will be described in Examples.

Measuring device: Rheometer 「Thermo SCIENTIFIC HAAKE MARS III」

Size of test sample: cylindrical shape with a diameter of 8 mm × a thickness of 300 μm

Test temperature: 80°C to 160°C

Frequency: 1Hz

Heating rate: 5°C/min

Number of measurements: 3 times (average value adopted)

As described above, the die-bonding sheet 10 of the present embodiment has a tensile modulus (tensile storage modulus E') at 150 ° C. after a thermal curing treatment at 150 ° C. for 1 hour, 0.5 MPa or more and 7.0 MPa or less,

0.7 MPa or more may be sufficient as this tensile elasticity modulus, and 1.1 Mpa or more may be sufficient as it. In addition, this tensile elasticity modulus may be 6.5 MPa or less, and may be 4.2 MPa or less.

Since the above-described tensile modulus is 0.5 MPa or more and 7.0 MPa or less, warpage of the die-bonding sheet 10 after the thermosetting treatment can be suppressed.

The tensile modulus of elasticity of the die-bonding sheet 10 can be increased, for example, by increasing the proportion of the constituent units of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer. On the other hand, for example, the tensile modulus of elasticity can be lowered by reducing the proportion of structural units of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer.

The above tensile modulus is measured under the following measurement conditions. Details of the measurement method are described in Examples.

Measuring Device: Solid Viscoelasticity Measuring Device

Size: Initial length 40mm, width 10mm

Heating rate: 10°C/min

Measurement temperature: 150°C in the temperature range of -30 to 280°C

Chuck Distance: 22.5mm

Frequency: 1Hz;

The value of the tensile storage modulus E' was taken as the above tensile modulus.

The glass transition point Tg of the die-bonding sheet 10 of the present embodiment may be 20°C or higher and 100°C or lower after a thermal curing treatment at 150°C for 1 hour.

This glass transition point Tg may be 25°C or higher, or 31°C or higher. In addition, such a glass transition point Tg may be 95°C or less, or 90°C or less.

When the above glass transition point Tg is 20°C or higher, there is an advantage that the adhesive strength of the die-bonding sheet 10 to the adherend is higher. In addition, when the above glass transition point Tg is 100° C. or less, generation of internal stress in the die-bonding sheet 10 due to the thermal curing treatment can be further suppressed, and therefore, the die-bonding sheet accompanying the thermal curing treatment ( The warpage of 10) can be more suppressed.

The glass transition point Tg of the die-bonding sheet 10 is determined by, for example, increasing the content ratio of the structural units of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer or blending the die-bonding sheet 10. It can be increased by increasing the amount of the curing agent or the like. On the other hand, for example, by reducing the content ratio of the structural unit of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer or by reducing the amount of the curing agent or the like blended in the die-bonding sheet 10, the glass transition point Tg can lower

In the die-bonding sheet 10 of the present embodiment, Tan δ in the glass transition point Tg measured as described above may be 0.7 or more and 1.5 or less.

Tan δ at such a glass transition point Tg may be 0.75 or more or 0.80 or more. In addition, Tan δ in such a glass transition point Tg may be 1.40 or less, and may be 1.35 or less.

When the Tan δ at the glass transition point Tg is 0.7 or more, the internal stress of the die-bonding sheet 10 that may be generated by the thermal curing treatment can be further alleviated. In addition, there is an advantage that the heat resistance of the die-bonding sheet 10 becomes better when the Tan δ in the above glass transition point Tg is 1.5 or less.

Tanδ in the glass transition point Tg of the die-bonding sheet 10 is determined by, for example, increasing the content ratio of the structural unit of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer or the die-bonding sheet 10 ) can be increased by increasing the amount of the curing agent or the like to be blended. On the other hand, by reducing the content ratio of the structural unit of the crosslinkable group-containing monomer constituting the crosslinkable acrylic polymer or by reducing the amount of the curing agent or the like blended in the die-bonding sheet 10, the glass transition point Tg Tanδ of can be lowered.

The above glass transition point Tg and Tanδ at the glass transition point Tg are calculated based on the storage modulus E' and the loss modulus E" obtained when measuring the tensile modulus described above.

While raising the temperature, the storage modulus E' and the loss modulus E" are measured, respectively, and Tan δ is calculated for each temperature by the formula of Tan δ = E"/E'. The higher the Tan δ, the higher the viscosity property.

The temperature at the time when Tan δ is the largest (at the top of the portion where Tan δ shows a peak shape) is taken as the above glass transition point Tg. Also, Tan δ at the glass transition point Tg is read.

In the die-bonding sheet 10 of the present embodiment, the elongation at break at 0°C may be 50% or less. Such elongation at break may be 45% or less, and may be 40% or less. In addition, 2% or more may be sufficient as said elongation at break.

The above breaking elongation is measured under the following measurement conditions.

Measuring Device: Tensile Testing Machine

Size of test piece: width 10 mm × length 40 mm

Initial Chuck Distance: 10mm

Temperature: 0℃

Tensile speed: 300mm/min

It is preferable that the above-mentioned crosslinkable acrylic polymer contains the most structural units of an alkyl (meth)acrylate monomer in terms of mass ratio among the structural units in the molecule. As the said alkyl (meth)acrylate monomer, C2-C18 alkyl (meth)acrylate monomers with 2 or more and 18 or less carbon atoms of an alkyl group (hydrocarbon group) are mentioned, for example.

As an alkyl (meth)acrylate monomer, a saturated linear alkyl (meth)acrylate monomer, a saturated branched chain alkyl (meth)acrylate monomer, a saturated cyclic alkyl (meth)acrylate monomer etc. are mentioned, for example.

As the saturated linear alkyl (meth) acrylate monomer, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl ( meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, tridecyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl ( Meth) acrylate, stearyl (meth) acrylate, etc. are mentioned. Moreover, it is preferable that carbon number of a linear alkyl group part is 2 or more and 8 or less.

As the saturated branched-chain alkyl (meth)acrylate monomer, isoheptyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, ) Acrylate etc. are mentioned. In addition, the alkyl group portion may have any of an iso structure, a sec structure, a neo structure, or a tert structure.

The above crosslinkable acrylic polymer contains a structural unit derived from an alkyl (meth)acrylate monomer and a crosslinkable group-containing monomer copolymerizable.

In the present embodiment, the crosslinkable acrylic polymer is an acrylic polymer obtained by copolymerization of at least an alkyl (meth)acrylate monomer and a crosslinkable group-containing monomer. In other words, the above crosslinkable acrylic polymer has a configuration in which structural units of an alkyl (meth)acrylate monomer and structural units of a crosslinkable group-containing monomer are connected in random order.

Examples of the crosslinkable group-containing monomer include a carboxyl group-containing (meth)acrylic monomer, an acid anhydride (meth)acrylic monomer, a hydroxyl group (hydroxyl group)-containing (meth)acrylic monomer, an epoxy group (glycidyl group)-containing (meth)acrylic monomer, and functional group-containing monomers such as isocyanate group-containing (meth)acrylic monomers, sulfonic acid group-containing (meth)acrylic monomers, phosphoric acid group-containing (meth)acrylic monomers, acrylamide, and acrylonitrile. In addition, the crosslinkable group-containing monomer may have an ether group or an ester group or the like in the molecule.

The crosslinkable acrylic polymer is preferably

At least one crosslinkable group-containing monomer selected from the group consisting of a carboxyl group-containing (meth)acrylic monomer, a hydroxyl group-containing (meth)acrylic monomer, an epoxy group-containing (meth)acrylic monomer, and an isocyanate-containing (meth)acrylic monomer, and an alkyl (meth)acrylic monomer ) It is a copolymer of acrylates (particularly, alkyl (meth)acrylates having 8 or less carbon atoms in the alkyl moiety).

As a (meth)acrylic monomer containing a carboxy group, (meth)acrylic acid, a mono(2-(meth)acryloyloxyethyl) succinate monomer, etc. are mentioned, for example. In addition, the carboxy group may be arranged at the terminal portion of the monomer structure, or may be bonded to hydrocarbons other than the terminal portion.

Examples of the hydroxy group-containing (meth)acrylic monomer include a hydroxyethyl (meth)acrylate monomer, a hydroxypropyl (meth)acrylate monomer, and a hydroxybutyl (meth)acrylate monomer. In addition, the hydroxyl group may be arranged at the terminal portion of the monomer structure, or may be bonded to hydrocarbons other than the terminal portion.

As an epoxy group-containing (meth)acryl monomer, a glycidyl (meth)acrylate monomer, 4-hydroxybutyl (meth)acrylate glycidyl ether, etc. are mentioned, for example. In addition, the epoxy group may be arranged at the terminal portion of the monomer structure, or may be bonded to hydrocarbons other than the terminal portion.

As an isocyanate group containing (meth)acrylic monomer, 2-methacryloyloxyethyl isocyanate etc. are mentioned, for example.

In the present embodiment, the crosslinkable acrylic polymer contains an epoxy group as a crosslinkable group, has a structural unit of glycidyl (meth)acrylate having the epoxy group in the molecule, and occupies the crosslinkable acrylic polymer It is preferable that it is 5 mass % or more and 50 mass % or less, and, as for the content rate of the structural unit of glycidyl (meth)acrylate, it is more preferable that it is 7 mass % or more and 40 mass % or less.

The die-bonding sheet 10 may also contain components other than the crosslinkable acrylic polymer described above. For example, the die-bonding sheet 10 may further contain at least one of a thermosetting resin or a thermoplastic resin other than the crosslinkable acrylic polymer described above.

As a thermosetting resin, an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, a silicone resin, a thermosetting polyimide resin etc. are mentioned, for example. As said thermosetting resin, only 1 type or 2 or more types are employ|adopted.

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, and phenol novolac type. , ortho cresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, hydantoin type, trisglycidyl isocyanurate type, or each of the glycidylamine type epoxy resins.

Phenol resins can act as curing agents for epoxy resins. Examples of the phenolic resin include polyoxystyrenes such as novolac-type phenolic resins, resol-type phenolic resins, and polyparaoxystyrene.

Examples of the novolak-type phenolic resin include phenol novolak resin, phenol aralkyl resin (biphenyl aralkyl type resin, phenol resin, etc.), cresol novolac resin, tert-butylphenol novolak resin, nonylphenol novolak resin, A phenol xylylene resin etc. are mentioned.

The hydroxyl equivalent [g/eq] of the phenol resin may be, for example, 90 or more and 220 or less.

From the viewpoint that the modulus of elasticity of the die-bonding sheet 10 can be appropriately lowered, the phenolic resin is preferably a biphenylaralkyl type resin phenolic resin having a relatively large hydroxyl equivalent.

As said phenol resin, only 1 type or 2 or more types are employ|adopted.

In the present embodiment, the die-bonding sheet 10 may also contain the above crosslinkable acrylic polymer and thermosetting resin, which undergo a crosslinking reaction with each other. In addition, the die-bonding sheet 10 may also contain a plurality of types of crosslinkable acrylic polymers that undergo a crosslinking reaction with each other.

Preferably, the die-bonding sheet 10 contains an epoxy group-containing acrylic polymer or an isocyanate group-containing acrylic polymer as a crosslinkable acrylic polymer, and further contains a phenol resin as a thermosetting resin. As a result, the die-bonding sheet 10 can be sufficiently cured by a cross-linking reaction between the epoxy group or isocyanate group of the cross-linkable acrylic polymer and the hydroxy group of the phenol resin.

More preferably, the die-bonding sheet 10 contains an epoxy group-containing acrylic polymer as a crosslinkable acrylic polymer and further contains a phenol resin as a thermosetting resin. As a result, the die-bonding sheet 10 can be sufficiently cured by a cross-linking reaction between the epoxy group of the cross-linkable acrylic polymer and the hydroxy group of the phenol resin. In this case, the hydroxyl equivalent of the phenol resin may be 160 or more and 250 or less.

In the die-bonding sheet 10, the hydroxyl group of the phenol resin is preferably 0.5 equivalent or more and 2.0 equivalent or less, more preferably 0.7 equivalent or more and 1.5 equivalent or less, per equivalent of the epoxy group of the epoxy group-containing acrylic polymer. In this way, the crosslinking reaction between the epoxy group-containing acrylic polymer and the phenol resin can be sufficiently promoted.

In addition, the die-bonding sheet 10 may contain a carboxyl group-containing acrylic polymer or a hydroxyl group-containing acrylic polymer as a crosslinkable acrylic polymer, and may also contain an epoxy resin as a thermosetting resin. As a result, the die-bonding sheet 10 can be sufficiently cured by a cross-linking reaction between the carboxy group or hydroxy group of the cross-linkable acrylic polymer and the epoxy group of the epoxy resin.

When the die-bonding sheet 10 contains a thermosetting resin such as an epoxy resin or a phenol resin, the content of the thermosetting resin in the die-bonding sheet 10 is preferably 35% by mass or less, and is less than 32% by mass. more preferable As a result, the die-bonding sheet 10 after the thermosetting treatment can have a lower elastic modulus. Therefore, warpage of the die-bonding sheet 10 accompanying the thermal curing treatment can be further suppressed.

Examples of thermoplastic resins other than the above crosslinkable functional group-containing acrylic polymer that can be included in the die-bonding sheet 10 include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid. Copolymers, ethylene-acrylic acid ester copolymers, polybutadiene resins, polycarbonate resins, thermoplastic polyimide resins, polyamide resins such as 6-polyamide resins and 6,6-polyamide resins, phenoxy resins, crosslinkable An acrylic resin that does not contain a functional group in its molecule, a saturated polyester resin such as PET or PBT, a polyamideimide resin, a fluororesin, and the like are exemplified.

As said thermoplastic resin, only 1 type or 2 or more types are employ|adopted.

In 100 parts by mass of the total mass of the die-bonding sheet 10, the content ratio of the crosslinkable acrylic polymer is preferably 50 parts by mass or more and 100 parts by mass or less, more preferably 55 parts by mass or more, and even more preferably It is 60 parts by mass or more.

In the die-bonding sheet 10, with respect to 100 parts by mass of organic components (eg, crosslinkable acrylic polymer, thermosetting resin, curing catalyst, etc., silane coupling agent, dye) excluding fillers, the above crosslinkability The content ratio of the acrylic polymer is preferably 50 parts by mass or more and 100 parts by mass or less, more preferably 60 parts by mass or more and 95 parts by mass or less, still more preferably 64 parts by mass or more. An organic component is a component other than a filler. In addition, the elasticity and viscosity of the die-bonding sheet 10 can be adjusted by changing the content of the thermosetting resin in the die-bonding sheet 10 .

On the other hand, the content ratio of the thermosetting resin may be 40 parts by mass or less with respect to 100 parts by mass of the organic component.

The die-bonding sheet 10 may or may not contain a filler. By changing the amount of filler in the die-bonding sheet 10, the elasticity and viscosity of the die-bonding sheet 10 can be more easily adjusted. In addition, the physical properties of the die-bonding sheet 10, such as conductivity, thermal conductivity, and modulus of elasticity, can be adjusted.

As a filler, an inorganic filler and an organic filler are mentioned. As a filler, an inorganic filler is preferable.

Examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, boron nitride, and silica such as crystalline silica and amorphous silica. Fillers containing Moreover, as a material of an inorganic filler, simple metals, alloys, etc., such as aluminum, gold, silver, copper, and nickel, are mentioned. A filler such as aluminum borate whisker, amorphous carbon black, or graphite may be used. The shape of the filler may be various shapes such as spherical shape, needle shape, and flake shape. As a filler, only said 1 type or 2 or more types is employ|adopted.

The average particle diameter of the filler may be, for example, 5 nm or more and 10 μm or less. The average particle diameter of the filler is preferably 5 nm or more and 500 nm or less, more preferably 5 nm or more and 100 nm or less. When the said average particle diameter is 5 nm or more, wettability and adhesiveness with respect to adherends, such as a semiconductor wafer, improve more. When the average particle diameter is 500 nm or less, the characteristics due to the added filler can be sufficiently exhibited, and the heat resistance of the die-bonding sheet 10 can be further exhibited. The average particle diameter of the filler can be obtained using, for example, a photometric particle size distribution analyzer (eg, product name "LA-910", manufactured by Horiba Seisakusho Co., Ltd.).

The specific surface area of the filler may be, for example, 35 m 2 /g or more and 400 m 2 /g or less. When the specific surface area is 35 m 2 /g or more, the -OH groups on the surface of the inorganic filler are relatively increased, and the crosslinking reaction by the thermal curing reaction proceeds more easily. In addition, a highly active crosslinkable group such as an epoxy group easily bonds to the surface of the inorganic filler. On the other hand, when the specific surface area is 400 m 2 /g or less, excessive bonding between highly active crosslinkable groups such as epoxy groups and the surface of the inorganic filler can be suppressed. The specific surface area of the filler is calculated by the BET method according to JIS Z8830:2013. Specifically, a sample is placed in a measurement cell, and after a heat treatment at 200°C for 30 minutes, a cooling treatment with liquid nitrogen is performed. In addition, the specific surface area is calculated from the amount of gas at the time of nitrogen release accompanying the heat treatment to be performed.

When the die-bonding sheet 10 contains a filler, the content of the filler may be 50% by mass or less, 40% by mass or less, or 30% by mass or less of the total mass of the die-bonding sheet 10 . Moreover, the content rate of the said filler may be 10 mass % or more, for example.

Preferably, the die-bonding sheet 10 of the present embodiment has a silica filler content of 40% by mass or less (may be 0% by mass) as an inorganic filler, and a specific surface area of the silica filler of 35 m 2 /g or more and 400 m 2 /g or less.

The die-bonding sheet 10 may contain other components as needed. As said other component, a curing catalyst, a flame retardant, a silane coupling agent, an ion trapping agent, dye etc. are mentioned, for example.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resin.

Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane. there is.

Examples of the ion trapping agent include hydrotalcites, bismuth hydroxide, and benzotriazole.

As said other additive, only 1 type or 2 or more types are employ|adopted.

The die-bonding sheet 10 preferably contains the aforementioned crosslinkable acrylic polymer, thermosetting resin, and filler in that elasticity and viscosity can be easily adjusted.

The thickness of the die-bonding sheet 10 is not particularly limited, but is, for example, 1 μm or more and 200 μm or less. This thickness may be 3 μm or more and 150 μm or less, or 5 μm or more and 100 μm or less. In the case where the die-bonding sheet 10 is a laminate, the above thickness is the total thickness of the laminate.

The die-bonding sheet 10 may have a single-layer structure, for example, as shown in FIG. 1 . In this specification, a single layer has only the layer formed with the same composition. A form in which a plurality of layers formed of the same composition are laminated is also a single layer.

On the other hand, the die-bonding sheet 10 may have a multilayer structure in which layers each formed of two or more different compositions are stacked, for example. When the die-bonding sheet 10 has a multi-layer structure, at least one layer constituting the die-bonding sheet 10 may contain the crosslinkable acrylic polymer described above and, if necessary, further contain a thermosetting resin.

Next, an embodiment of the dicing die-bonding film according to the present invention will be described.

The dicing die-bonding film 1 of the present embodiment includes the die-bonding sheet 10 described above and the dicing tape 20 bonded to the die-bonding sheet 10 .

In the dicing die-bonding film 1 of the present embodiment, when used, the pressure-sensitive adhesive layer 22 is cured by being irradiated with active energy rays (eg, ultraviolet rays). In detail, in a state in which the die-bonding sheet 10 having a semiconductor wafer bonded to one side thereof and the pressure-sensitive adhesive layer 22 bonded to the other side of the die-bonding sheet 10 are laminated, at least ultraviolet rays, etc. Layer 22 is irradiated. For example, ultraviolet rays or the like are irradiated from the side where the substrate layer 21 is disposed, and the ultraviolet rays or the like passing through the substrate layer 21 are transmitted to the pressure-sensitive adhesive layer 22 . The pressure-sensitive adhesive layer 22 is cured by irradiation with ultraviolet rays or the like.

Since the adhesive force of the pressure-sensitive adhesive layer 22 can be lowered by curing the pressure-sensitive adhesive layer 22 after irradiation, the die-bonding sheet 10 (a state in which the semiconductor wafer is bonded) can be relatively easily removed from the pressure-sensitive adhesive layer 22 after irradiation. can be peeled off.

<Dicing tape of dicing die-bonding film>

The above dicing tape 20 is usually a long sheet, and is stored in a rolled state until used. The dicing die-bonding film 1 of the present embodiment is applied to a circular annular frame having an inner diameter much larger than that of the silicon wafer to be cut, and then cut and used.

The dicing tape 20 described above includes a substrate layer 21 and an adhesive layer 22 overlapping the substrate layer 21 .

The substrate layer 21 may have a single layer structure or a laminated structure.

Each layer of the substrate layer 21 is, for example, a metal foil, a fiber sheet such as paper or cloth, a rubber sheet, a resin film, or the like.

As the fibrous sheet constituting the substrate layer 21, paper, woven fabric, non-woven fabric, and the like are exemplified.

Examples of the material of the resin film include polyolefins such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymer; Ethylene copolymers, such as an ethylene-vinyl acetate copolymer (EVA), an ionomer resin, an ethylene-(meth)acrylic acid copolymer, and an ethylene-(meth)acrylic acid ester (random, alternating) copolymer; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); polyacrylate; polyvinyl chloride (PVC); Polyurethane; polycarbonate; polyphenylene sulfide (PPS); polyamides such as aliphatic polyamides and wholly aromatic polyamides (aramids); polyetheretherketone (PEEK); polyimide; polyetherimide; polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene copolymer); cellulose or cellulose derivatives; silicone-containing polymers; A fluorine-containing polymer etc. are mentioned. These may be used individually by 1 type or in combination of 2 or more types.

The substrate layer 21 is preferably made of a polymer material such as a resin film.

When the base material layer 21 has a resin film, the resin film may be subjected to stretching treatment or the like to control deformability such as elongation.

Surface treatment may be given to the surface of the base material layer 21 in order to improve adhesiveness with the adhesive layer 22. As the surface treatment, for example, chemical methods such as chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, ionizing radiation treatment, or oxidation treatment by physical methods or the like can be employed. In addition, coating treatment with a coating agent such as an anchor coating agent, a primer, or an adhesive may be performed.

The substrate layer 21 may be a single layer or may be composed of a plurality of layers (for example, three layers). The thickness (total thickness) of the substrate layer 21 may be 80 μm or more and 150 μm or less.

In order to impart peelability to the back side of the substrate layer 21 (the side on which the pressure-sensitive adhesive layer 22 does not overlap), for example, a release treatment is performed with a release agent (release agent) such as a silicone-based resin or a fluorine-based resin. There may be.

The base material layer 21 is preferably a light-transmitting (ultraviolet-ray-transmitting) resin film or the like in view of enabling application of active energy rays such as ultraviolet rays to the pressure-sensitive adhesive layer 22 from the back side.

Even if the dicing tape 20 described above is provided with a release liner covering one surface of the pressure-sensitive adhesive layer 22 (the surface on which the pressure-sensitive adhesive layer 22 does not overlap with the substrate layer 21) in a state before use. do. The release liner is used to protect the pressure-sensitive adhesive layer 22 and is peeled off before attaching the die-bonding sheet 10 to the pressure-sensitive adhesive layer 22 .

As the release liner, for example, a silicone type release agent, a long-chain alkyl type release agent, a fluorine type release agent, or a plastic film or paper surface-treated with a release agent such as molybdenum sulfide can be used.

In addition, the release liner can be used as a support material for supporting the pressure-sensitive adhesive layer 22 . In particular, the peeling liner is suitably used when overlapping the pressure-sensitive adhesive layer 22 on the substrate layer 21 . Specifically, in a state in which the release liner and the pressure-sensitive adhesive layer 22 are laminated, the pressure-sensitive adhesive layer 22 is overlapped on the substrate layer 21, and the release liner is peeled off (transferred) after the overlapping, so that on the substrate layer 21 The pressure-sensitive adhesive layer 22 may be overlapped.

In this embodiment, the pressure-sensitive adhesive layer 22 contains, for example, an acrylic polymer compound, an isocyanate compound, and a polymerization initiator.

The pressure-sensitive adhesive layer 22 may have a thickness of 5 μm or more and 40 μm or less. The shape and size of the pressure-sensitive adhesive layer 22 are usually the same as those of the base layer 21 .

The acrylic polymer compound has at least a structural unit of an alkyl (meth)acrylate, a structural unit of a hydroxyl group-containing (meth)acrylate, and a structural unit of a polymerizable group-containing (meth)acrylate in its molecule. The structural unit is a unit constituting the main chain of the acrylic polymer compound. Each side chain in the above acrylic polymer compound is included in each structural unit constituting the main chain.

In the acrylic polymer compound included in the pressure-sensitive adhesive layer 22, the above structural units can be confirmed by NMR analysis such as ¹ H-NMR and ¹³ C-NMR, thermal decomposition GC/MS analysis, infrared spectroscopy, and the like. In addition, the molar ratio of the above constituent units in the acrylic polymer compound is usually calculated from the compounding amount (charged amount) when polymerizing the acrylic polymer compound.

The structural unit of said alkyl (meth)acrylate originates in an alkyl (meth)acrylate monomer. In other words, the molecular structure after polymerization of the alkyl (meth)acrylate monomer is the structural unit of the alkyl (meth)acrylate. The term "alkyl" indicates the number of carbon atoms in the hydrocarbon moiety esterified with (meth)acrylic acid.

The hydrocarbon portion of the alkyl moiety in the structural unit of the alkyl (meth)acrylate may be either a saturated hydrocarbon or an unsaturated hydrocarbon. The number of carbon atoms in the hydrocarbon portion may be 6 or more and 10 or less.

As a structural unit of alkyl (meth)acrylate, for example, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n- or iso-nonyl (meth)acrylate, decyl (meth)acrylate, etc. Each constituent unit of

An acrylic high molecular compound has a structural unit of (meth)acrylate containing a hydroxyl group, and the hydroxyl group of this structural unit easily reacts with an isocyanate group.

By coexisting an acrylic polymer compound having a structural unit of hydroxyl group-containing (meth)acrylate and an isocyanate compound in the pressure-sensitive adhesive layer 22, the pressure-sensitive adhesive layer 22 can be appropriately cured. Therefore, the acrylic polymer compound can sufficiently gel. Therefore, the pressure-sensitive adhesive layer 22 can exhibit adhesive performance while maintaining its shape.

It is preferable that the structural unit of the hydroxyl group-containing (meth)acrylate is a hydroxyl group-containing C2-C4 alkyl (meth)acrylate structural unit. The expression “C2 to C4 alkyl” indicates the number of carbon atoms in the hydrocarbon moiety esterified with (meth)acrylic acid. In other words, the hydroxyl group-containing C2 to C4 alkyl (meth)acrylic monomer represents a monomer in which (meth)acrylic acid and an alcohol having 2 or more and 4 or less carbon atoms (usually a dihydric alcohol) are ester-bonded.

The hydrocarbon portion of the C2 to C4 alkyl is usually a saturated hydrocarbon. For example, the hydrocarbon portion of C2 to C4 alkyl is a straight-chain saturated hydrocarbon or a branched-chain saturated hydrocarbon. It is preferable that the hydrocarbon moiety of C2 to C4 alkyl does not contain a polar group containing oxygen (O) or nitrogen (N).

As a structural unit of hydroxyl-containing C2-C4 alkyl (meth)acrylate, for example, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxyn-butyl (meth)acrylate, or and each constituent unit of hydroxybutyl (meth)acrylate such as hydroxyiso-butyl (meth)acrylate. In addition, in the structural unit of hydroxybutyl (meth)acrylate, the hydroxyl group (-OH group) may be bonded to the terminal carbon (C) of the hydrocarbon moiety, or bonded to carbon (C) other than the terminal of the hydrocarbon moiety, There may be.

The acrylic polymer compound described above includes a polymerizable group-containing (meth)acrylate structural unit having a polymerizable unsaturated double bond in its side chain.

Since the acrylic polymer compound contains a polymerizable group-containing (meth)acrylate structural unit, the pressure-sensitive adhesive layer 22 can be cured by irradiation with active energy rays (ultraviolet rays, etc.) before the pick-up step. In detail, radicals are generated from the photopolymerization initiator by irradiation with active energy rays such as ultraviolet rays, and acrylic high molecular compounds can be crosslinked with each other by the action of the radicals. Thereby, the adhesive force of the adhesive layer 22 before irradiation can be reduced by irradiation. Then, the die-bonding sheet 10 can be satisfactorily separated from the pressure-sensitive adhesive layer 22 .

In addition, as an active energy ray, an ultraviolet ray, radiation, and an electron beam are employ|adopted.

The structural unit of the polymerizable group-containing (meth)acrylate is, specifically, a molecular structure in which the isocyanate group of the isocyanate group-containing (meth)acryl monomer is bonded to the hydroxyl group in the structural unit of the above-mentioned hydroxyl group-containing (meth)acrylate through a urethane bond. may have

The constituent unit of the polymerizable group-containing (meth)acrylate having a polymerizable group can be prepared after polymerization of the acrylic polymer compound. For example, after copolymerization of an alkyl (meth)acrylate monomer and a hydroxyl group-containing (meth)acrylic monomer, the hydroxyl group in some of the structural units of the hydroxyl group-containing (meth)acrylate and the isocyanate group of the isocyanate group-containing polymerizable monomer , By carrying out a urethanization reaction, the structural unit of the polymerizable group-containing (meth)acrylate can be obtained.

It is preferable that the said isocyanate group-containing (meth)acrylic monomer has one isocyanate group in a molecule|numerator and also has one (meth)acryloyl group. As such a monomer, 2-methacryloyloxyethyl isocyanate is mentioned, for example.

The pressure-sensitive adhesive layer 22 of the dicing tape 20 in this embodiment further contains an isocyanate compound. A part of the isocyanate compound may be in a state after reacting by a urethanization reaction or the like.

An isocyanate compound has a plurality of isocyanate groups in its molecule. When the isocyanate compound has a plurality of isocyanate groups in its molecule, a crosslinking reaction between acrylic polymer compounds in the pressure-sensitive adhesive layer 22 can be promoted. Specifically, a crosslinking reaction through an isocyanate compound can be promoted by reacting one isocyanate group of an isocyanate compound with a hydroxyl group of an acrylic polymer compound and reacting the other isocyanate group with a hydroxyl group of another acrylic polymer compound.

As an isocyanate compound, diisocyanate, such as aliphatic diisocyanate, alicyclic diisocyanate, or aromatic aliphatic diisocyanate, is mentioned, for example.

Moreover, as an isocyanate compound, polymeric polyisocyanate, such as a dimer and a trimer of diisocyanate, and polymethylene polyphenylene polyisocyanate are mentioned, for example.

Moreover, as an isocyanate compound, the polyisocyanate which made the excessive amount of the above-mentioned isocyanate compound and an active hydrogen containing compound react, for example is mentioned. Examples of active hydrogen-containing compounds include active hydrogen-containing low-molecular-weight compounds and active hydrogen-containing high-molecular-weight compounds.

Moreover, as an isocyanate compound, allophanate-ized polyisocyanate, buret-ized polyisocyanate, etc. can be used.

Said isocyanate compound can be used individually by 1 type or in combination of 2 or more types.

As said isocyanate compound, the reaction product of aromatic diisocyanate and a low molecular-weight compound containing an active hydrogen is preferable. Since the reaction rate of an isocyanate group is comparatively slow for the reaction material of aromatic diisocyanate, excessive hardening of the adhesive layer 22 containing such a reaction material is suppressed. As said isocyanate compound, what has 3 or more isocyanate groups in a molecule|numerator is preferable.

The polymerization initiator contained in the pressure-sensitive adhesive layer 22 is a compound capable of initiating a polymerization reaction by added energy of heat or light. When the pressure-sensitive adhesive layer 22 contains a polymerization initiator, when heat energy or light energy is applied to the pressure-sensitive adhesive layer 22, a crosslinking reaction between acrylic polymer compounds can be promoted. Specifically, between the acrylic polymer compounds having the constituent units of polymerizable group-containing (meth)acrylate, a polymerization reaction between the polymerizable groups is initiated, and the pressure-sensitive adhesive layer 22 can be cured. In this way, the adhesive strength of the pressure-sensitive adhesive layer 22 is reduced, and the die-bonding sheet 10 can be easily peeled off from the cured pressure-sensitive adhesive layer 22 in the pick-up step.

As a polymerization initiator, a photoinitiator or a thermal polymerization initiator etc. are employ|adopted, for example. As a polymerization initiator, a general commercial product can be used.

The pressure-sensitive adhesive layer 22 may further contain other components other than the components described above. Examples of other components include tackifiers, plasticizers, fillers, anti-aging agents, antioxidants, ultraviolet absorbers, light stabilizers, heat-resistant stabilizers, antistatic agents, surfactants, light release agents and the like. The type and usage amount of other components may be appropriately selected depending on the purpose.

In the dicing die-bonding film 1 of the present embodiment, in a state before use, one surface of the die-bonding sheet 10 (the surface on which the die-bonding sheet 10 does not overlap the pressure-sensitive adhesive layer 22) You may provide a peeling liner covering. The release liner is used to protect the die-bonding sheet 10, and is peeled off immediately before attaching an adherend (for example, a semiconductor wafer) to the die-bonding sheet 10.

This release liner can be used as a support material for supporting the die-bonding sheet 10 . The release liner is suitably used when the die-bonding sheet 10 is overlapped on the pressure-sensitive adhesive layer 22 . In detail, the die-bonding sheet 10 is overlapped on the pressure-sensitive adhesive layer 22 in a state where the release liner and the die-bonding sheet 10 are stacked, and the release liner is peeled off (transferred) after the overlapping, so that the pressure-sensitive adhesive layer 22 ), the die-bonding sheet 10 may be overlapped.

Subsequently, the manufacturing method of the die-bonding sheet 10 and the dicing die-bonding film 1 of this embodiment is demonstrated.

<Method of manufacturing dicing die-bonding film>

The manufacturing method of the dicing die-bonding film 1 of this embodiment,

A process of manufacturing the die-bonding sheet 10;

A process of producing the dicing tape 20;

A process of overlapping the manufactured die-bonding sheet 10 and the dicing tape 20 is provided.

<Process of producing die-bonding sheet (thermosetting resin sheet)>

The process of manufacturing the die-bonding sheet 10,

A resin composition preparation step of preparing a resin composition for forming the die-bonding sheet 10;

A die-bonding sheet forming step of forming the die-bonding sheet 10 from the resin composition is provided.

In the resin composition preparation step, a resin composition is prepared by, for example, mixing the above crosslinkable acrylic polymer with an epoxy resin, a curing catalyst for an epoxy resin, a phenol resin, or a solvent and dissolving each resin in a solvent . By varying the amount of solvent, the viscosity of the composition can be adjusted. In addition, as these resins, commercially available products can be used.

In the die-bonding sheet formation step, the resin composition prepared as described above is applied to a release liner, for example. It does not specifically limit as a coating method, For example, general coating methods, such as roll coating, screen coating, and gravure coating, are employ|adopted. Subsequently, the die-bonding sheet 10 is formed by solidifying the applied composition by desolvation treatment, curing treatment, or the like, if necessary.

<Process of manufacturing dicing tape>

The process of producing a dicing tape,

A synthesis process of synthesizing an acrylic polymer compound;

A pressure-sensitive adhesive layer manufacturing step of preparing the pressure-sensitive adhesive layer 22 by evaporating the solvent from the pressure-sensitive adhesive composition containing the above-mentioned acrylic polymer compound, isocyanate compound, polymerization initiator, solvent, and other components appropriately added according to the purpose; ,

A substrate layer manufacturing process for producing the substrate layer 21;

A lamination step of laminating the base material layer 21 and the pressure-sensitive adhesive layer 22 is provided by bonding the pressure-sensitive adhesive layer 22 and the base layer 21 together.

In the synthesis step, for example, an acrylic polymer intermediate is synthesized by radically polymerizing a C9 to C11 alkyl (meth)acrylate monomer having 9 or more and 11 or less carbon atoms in the hydrocarbon portion and a (meth)acrylic monomer containing a hydroxyl group.

Radical polymerization can be performed by a general method. For example, an acrylic polymer compound intermediate can be synthesized by dissolving each of the above monomers in a solvent, stirring while heating, and adding a polymerization initiator. In order to adjust the molecular weight of the acrylic polymer compound, polymerization may be performed in the presence of a chain transfer agent.

Subsequently, the hydroxyl group of a part of the structural unit of the hydroxyl group-containing (meth)acrylate contained in the intermediate of the acrylic polymer compound and the isocyanate group of the isocyanate group-containing polymerizable monomer are bonded by a urethanization reaction. Thereby, some structural units of the hydroxyl group-containing (meth)acrylate become structural units of the polymerizable group-containing (meth)acrylate.

The urethanization reaction can be performed by a general method. For example, the acrylic high molecular compound intermediate and the isocyanate group-containing polymerizable monomer are stirred while heating in the presence of a solvent and a urethanization catalyst. As a result, the isocyanate group of the isocyanate group-containing polymerizable monomer can be urethane-bonded to a part of the hydroxyl groups of the intermediate of the acrylic polymer compound.

In the pressure-sensitive adhesive layer preparation step, for example, an acrylic polymer compound, an isocyanate compound, and a polymerization initiator are dissolved in a solvent to prepare an adhesive composition. By varying the amount of solvent, the viscosity of the composition can be adjusted. Then, the pressure-sensitive adhesive composition is applied to the release liner. As a coating method, general coating methods, such as roll coating, screen coating, and gravure coating, are employ|adopted, for example. The applied composition is subjected to desolvation treatment or solidification treatment to solidify the applied pressure-sensitive adhesive composition to form the pressure-sensitive adhesive layer 22 .

In the substrate layer preparation step, a substrate layer can be produced by forming a film by a general method. Examples of the film forming method include a calender film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, and a dry lamination method. A coextrusion molding method may be employed. In addition, as the substrate layer 21, you may use a commercially available film or the like.

In the lamination process, the pressure-sensitive adhesive layer 22 and the substrate layer 21 in a state of overlapping with the release liner are overlapped and laminated. In addition, the peeling liner may be in a state overlapped with the pressure-sensitive adhesive layer 22 until use.

In addition, in order to promote the reaction between the crosslinking agent and the acrylic polymer compound, and also to promote the reaction between the crosslinking agent and the surface portion of the base material layer 21, an aging treatment step is performed in a 50°C environment for 48 hours after the lamination step. can also

The dicing tape 20 can be manufactured by these processes.

<Step of overlapping die-bonding sheet 10 and dicing tape 20>

In the step of overlapping the die-bonding sheet 10 and the dicing tape 20, the die-bonding sheet 10 is attached to the pressure-sensitive adhesive layer 22 of the dicing tape 20 manufactured as described above.

In such pasting, the release liner is separated from the pressure-sensitive adhesive layer 22 of the dicing tape 20 and the die-bonding sheet 10, respectively, and the die-bonding sheet 10 and the pressure-sensitive adhesive layer 22 are brought into direct contact with each other. join For example, it can join by crimping. The temperature at the time of bonding is not particularly limited, and is, for example, 30°C or more and 50°C or less, and preferably 35°C or more and 45°C or less. The linear pressure at the time of bonding is not particularly limited, but is preferably 0.1 kgf/cm or more and 20 kgf/cm or less, and more preferably 1 kgf/cm or more and 10 kgf/cm or less.

In addition, you may harden the adhesive layer 22 to some extent by irradiating an ultraviolet-ray etc. to the adhesive layer 22 of the dicing tape 20 before said sticking. Thereby, the adhesive force of the adhesive layer 22 can be reduced suitably, the storage stability of the adhesive layer 22 can be improved, and therefore, the pick-up property at the time of picking up a semiconductor chip can be made more favorable.

Through the above steps, the dicing die-bonding film 1 manufactured as described above is used as an auxiliary tool for manufacturing a semiconductor device (semiconductor integrated circuit), for example. The thermosetting resin sheet of the present embodiment is used as a die-bonding sheet for adhering the chip to the adherend in a method of manufacturing a semiconductor device by placing a wafer having a circuit surface formed thereon between a cut chip and an adherend. do. Hereinafter, specific examples of use of the dicing die-bonding film 1 will be described.

<How to use dicing die-bonding film when manufacturing semiconductor devices>

A method of manufacturing a semiconductor device generally includes a step of cutting out and assembling a chip from a semiconductor wafer on which a circuit surface is formed.

This step includes, for example, a stealth dicing step in which a weak portion is formed inside a semiconductor wafer to which a backgrind tape is attached by means of a laser beam, and the semiconductor wafer is prepared to be processed into chips (dies) by a cutting process. , a back-grind step of grinding the semiconductor wafer to which the back-grind tape is attached to reduce the thickness, and attaching one surface of the thinned semiconductor wafer (for example, the surface opposite to the circuit surface) to the die-bonding sheet 10 and a mount process of fixing the semiconductor wafer to the dicing tape 20, and an expand process of cutting the semiconductor wafer by stretching the dicing tape 20 to fabricate chips (dies) and widening the gap between the chips. And, a pick-up step of peeling between the die-bonding sheet 10 and the pressure-sensitive adhesive layer 22 and taking out the semiconductor chip (die) in the state where the die-bonding sheet 10 is attached, and the die bond attached to the semiconductor chip (die) A die-bonding process of adhering the sheet 10 to an adherend, a curing process of curing the die-bonding sheet 10 adhered to the adherend, and an electrode and an adherend of an electronic circuit in a semiconductor chip (die) It has a wire bonding process of electrically connecting with a wire, and a sealing process of sealing the semiconductor chip (die) and wire on an adherend with a thermosetting resin. When performing these processes, the dicing tape (dicing die-bonding film) of this embodiment is used as a manufacturing auxiliary tool.

The stealth dicing process is a process in a so-called SDBG (Stealth Dicing Before Grinding) process. In the stealth dicing process, as shown in FIGS. 2A to 2C , a weak portion for cutting the semiconductor device into small pieces (dies) is formed inside the semiconductor wafer W. In detail, the back grind tape G is affixed to the circuit surface of the semiconductor wafer W (refer to FIG. 2A). With the back grinding tape G attached, grinding processing (pre-back grinding processing) is performed by the grinding pad K until the semiconductor wafer W reaches a predetermined thickness (see FIG. 2B ). A weak portion is formed inside the semiconductor wafer W by making the laser beam hit the semiconductor wafer W having a reduced thickness (see FIG. 2C).

Instead of the stealth dicing process, you may perform a half-cutting process. The half-cut process is a process in a so-called DBG (Dicing Before Grinding) process.

In the half-cut process, in order to process the semiconductor wafer into chips (dies) by cutting, grooves are formed in the semiconductor wafer, and then the semiconductor wafer is ground to make it thinner.

Specifically, in the half-cutting step, half-cutting is performed to cut the semiconductor device into small pieces (dies). More specifically, the tape for a wafer process is affixed to the surface on the opposite side to the circuit surface of a semiconductor wafer. Further, a dicing ring is installed on the tape for wafer processing. In the state where the tape for wafer processing is attached, grooves for division are formed. While a back grind tape is affixed on the surface in which the groove was formed, the tape for a wafer process affixed first is peeled off.

As described above, the die-bonding sheet and the dicing die-bonding film of the present embodiment are used in the Stealth Dicing Before Grinding (SDBG) process or the Dicing Before Grinding (DBG) process for manufacturing semiconductor chips by cutting a semiconductor wafer. desirable.

In the back grinding process, as shown in FIG. 2D , grinding processing is further performed on the semiconductor wafer W with the back grinding tape G attached, and the thickness of the chip (die) produced by subsequent cutting The thickness of the semiconductor wafer W is thinned until

In the mounting process, the semiconductor wafer W is fixed to the dicing tape 20 as shown in FIGS. 3A to 3B . In detail, while providing the dicing ring R on the pressure-sensitive adhesive layer 22 of the dicing tape 20, on the surface of the exposed die-bonding sheet 10, a semiconductor whose thickness has been reduced by cutting as described above A wafer W is attached (see FIG. 3A). Then, the back grind tape G is peeled from the semiconductor wafer W (refer to FIG. 3B).

In the expand step, as shown in Figs. 4A to 4C, the space between semiconductor chips (dies) X manufactured by cutting is widened. In detail, after attaching the dicing ring R to the pressure-sensitive adhesive layer 22 of the dicing tape 20, it is fixed to the holder H of the expander (see Fig. 4A). The dicing die-bonding film 1 is expanded so as to expand in the plane direction by pushing up the pushing member U provided in the expander from the lower side of the dicing die-bonding film 1 (see Fig. 4B). . In this way, the semiconductor wafer W and the die-bonding sheet 10 are cut under a specific temperature condition. The temperature conditions are, for example, -20°C or more and 0°C or less, preferably -15°C or more and 0°C or less, and more preferably -10°C or more and -5°C or less. By lowering the lifting member U, the expand state is released (refer to FIG. 4C up to this low-temperature expand step).

In addition, in the expand process, as shown in FIGS. 5A and 5B, the dicing tape 20 is stretched to expand the area under higher temperature conditions (for example, 10°C to 25°C). Thereby, after cutting, the adjacent semiconductor chips X are separated in the plane direction of the film plane, and the caph (interval) is further expanded (room temperature expand step).

In the pick-up step, as shown in FIG. 6 , the semiconductor chip X to which the piece 10' of the die-bonding sheet is attached is peeled from the pressure-sensitive adhesive layer 22 of the dicing tape 20 . In detail, the pin member P is raised, and the semiconductor chip X to be picked up is pushed up through the dicing tape 20 . The pushed-up semiconductor chip X and the small piece 10' of the die-bonding sheet are held by a suction jig J.

In the die-bonding step, as shown in Fig. 7, the semiconductor chip X with the piece 10' of the die-bonding sheet attached thereto is bonded to the adherend Z. In the die-bonding step, for example, as shown in FIG. 9 , semiconductor chips X in a state where small pieces 10' of die-bonding sheets are attached may be stacked multiple times. In this way, when manufacturing a chip-embedded semiconductor device (FOD [Film on Die] type semiconductor device), the die-bonding sheet 10 may be used to embed the semiconductor chip.

In this case, the piece 10' of the die-bonding sheet used to embed the semiconductor chip is adhered to the surface of the adherend with irregularities. When the small piece 10' of the die-bonding sheet is adhered to the uneven surface, the small piece 10' of the die-bonding sheet needs to be deformed to fill the concave portion. That is, the small piece 10' of the die-bonding sheet needs to follow the concavo-convex shape. If this followability is low, a void (gap) V may be formed, for example, as shown in FIG. 8 .

Since the die-bonding sheet 10 of the present embodiment has the above-described good embeddability, it is possible to suppress the occurrence of such gaps V.

In the curing step, the reaction activity of the crosslinkable group (for example, epoxy group) in the crosslinkable acrylic polymer described above contained in the small piece 10' of the die-bonding sheet is increased to cure the small piece 10' of the die-bonding sheet. In order to advance, heat treatment is performed at a temperature of, for example, 80°C or higher and 175°C or lower.

In the wire bonding step, as shown in FIG. 9 , the semiconductor chip X (die) and the adherend Z are connected with a wire L while being heated. Therefore, the crosslinkable groups in the above-described crosslinkable acrylic polymer contained in the small piece 10' of the die-bonding sheet become reactive again by heating, and the curing reaction of the small piece 10' of the die-bonding sheet begins. can proceed

Also, in the wire bonding process, a compressive force may be applied to the die-bonding sheet 10 in the thickness direction in some cases.

In the sealing step, as shown in Fig. 10, the semiconductor chip X (die) and the piece 10' of the die-bonding sheet are sealed with a thermosetting resin M such as an epoxy resin. In the sealing step, in order to advance the curing reaction of the thermosetting resin (M), heat treatment is performed at a temperature of, for example, 150°C or more and 200°C or less.

Further, in the semiconductor industry in recent years, with the new development of integration technology, thinner semiconductor chips (for example, 20 μm or more and 50 μm or less) and thinner die-bonding sheets (for example, 1 μm or more and 40 μm or less) or less, preferably 7 μm or less, more preferably 5 μm or less) is desired. In addition, thinner adherends are also desired.

An electronic circuit is formed on one surface of such a thin semiconductor chip. When an electronic circuit is formed on one side of a thin semiconductor chip, the semiconductor chip cannot withstand the internal stress to the end, and as shown in FIG. 10"), deformation (bending, etc.) may occur.

If lamination is performed multiple times as described above in a state where the die-bonding sheet is attached to such a semiconductor chip, so-called lifting may occur due to poor adhesion of the die-bonding sheet and the chip (die).

In addition, as described above, warpage may occur in the die-bonding sheet also due to internal stress of the die-bonding sheet accompanying the thermal curing treatment. Therefore, the thinner the adherend and the semiconductor chip bonded to the die-bonding sheet are, the easier it is for warpage to occur in the adherend and the semiconductor chip as well.

Since the die-bonding sheet 10 of the present embodiment has specific physical properties, it is possible to suppress the lifting as described above, and also to suppress the phenomenon of bending of adherends and semiconductor chips.

The thermosetting resin sheet (die-bonding sheet) and dicing die-bonding film of this embodiment are as described above, but the present invention is not limited to the die-bonding sheet and dicing die-bonding film of the above example.

That is, various forms used in general die-bonding sheets and dicing die-bonding films can be employed within a range that does not impair the effects of the present invention.

Matters disclosed by this specification include the following.

(One)

A crosslinkable acrylic polymer having a crosslinkable group in its molecule that causes a crosslinking reaction by heat curing treatment,

The shear loss modulus G" at 140 ° C. before the thermal curing treatment is 1 kPa or more and 20 kPa or less, and the tensile modulus at 150 ° C. after the thermal curing treatment for 1 hour at 150 ° C. is 0.5 MPa or more and 7.0 MPa or less. Die-bonding sheet (thermosetting resin sheet).

(2)

The die-bonding sheet (thermosetting resin sheet) according to (1) above, wherein the content ratio of the crosslinkable acrylic polymer to 100 parts by mass of the organic component contained in the die-bonding sheet is 50 parts by mass or more and 100 parts by mass or less.

(3)

The glass transition point Tg after a thermal curing treatment at 150°C for 1 hour is 20°C or more and 100°C or less, and the Tan δ at the glass transition point Tg is 0.7 or more and 1.5 or less as described in (1) or (2) above. Die-bonding sheet (thermosetting resin sheet).

(4)

The crosslinkable group includes an epoxy group,

The crosslinkable acrylic polymer has a structural unit of glycidyl (meth)acrylate having an epoxy group in a molecule,

The die-bonding sheet (thermosetting resin sheet) according to any one of (1) to (3) above, wherein the content of the structural unit in the crosslinkable acrylic polymer is 5% by mass or more and 50% by mass or less.

(5)

The content of the silica filler as an inorganic filler is 40% by mass or less,

The die-bonding sheet (thermosetting resin sheet) according to any one of (1) to (4) above, wherein the silica filler has a specific surface area of 35 m 2 /g or more and 400 m 2 /g or less.

(6)

A phenolic resin that crosslinks with the crosslinkable group by the heat curing treatment,

The die-bonding sheet (heat-curable resin sheet) according to any one of (1) to (5) above, wherein the hydroxyl equivalent of the phenol resin is 160 or more.

(7)

The die-bonding sheet according to any one of (1) to (6) above, containing one or more crosslinkable acrylic polymers, and having a mass average molecular weight of at least one crosslinkable acrylic polymer of 10,000 or more and 400,000 or less ( thermosetting resin sheet).

(8)

The die-bonding sheet (thermosetting resin sheet) according to any one of (1) to (7) above, which is used by bonding with a dicing tape.

(9)

The die-bonding sheet (thermosetting resin sheet) according to any one of (1) to (8) above, wherein the elongation at break at 0°C is 50% or less.

(10)

The die-bonding sheet according to any one of (1) to (9) above (thermosetting resin Sheet).

(11)

The die-bonding sheet (thermosetting resin sheet) according to any one of (1) to (10) above, comprising at least one of an epoxy group-containing acrylic polymer and an isocyanate group-containing acrylic polymer as the crosslinkable acrylic polymer.

(12)

The die-bonding sheet (thermosetting resin sheet) according to (11) above, further comprising at least one of a phenol resin as a thermosetting resin and a silica filler as an inorganic filler.

(13)

Any one of (1) to (11) above, comprising at least one of an epoxy group-containing acrylic polymer and an isocyanate group-containing acrylic polymer and at least one of a hydroxyl group-containing acrylic polymer and a carboxyl group-containing acrylic polymer as the crosslinkable acrylic polymer. Die-bonding sheet (thermosetting resin sheet).

(14)

A dicing die-bonding film comprising the die-bonding sheet according to any one of (1) to (13) above and a dicing tape bonded to the die-bonding sheet.

[Example]

Next, the present invention will be explained in more detail by means of experimental examples, but the present invention is not limited thereto.

A die-bonding sheet was manufactured as follows. Further, this die-bonding sheet was bonded to a dicing tape to prepare a dicing die-bonding film.

<Production of dicing tape>

Each of the following raw materials was placed in a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer, and a stirring device. Polymerization was performed at 60°C for 10 hours in a nitrogen atmosphere to obtain an acrylic polymer compound A.

2-ethylhexyl acrylate (2EHA): 100 parts by mass;

2-hydroxyethyl acrylate (HEA): 26 parts by mass;

Benzoyl peroxide: 0.4 parts by mass,

Toluene: 80 parts by mass,

1.2 parts by mass of 2-methacryloyloxyethyl isocyanate (hereinafter also referred to as MOI) was added to the liquid containing the acrylic polymer compound A obtained by polymerization as described above. Thereafter, an addition reaction treatment was performed at 50°C for 60 hours in an air current to obtain an acrylic polymer compound A'.

Next, an adhesive solution was prepared by adding the following ingredients to 100 parts of the acrylic polymer compound A'.

・Polyisocyanate compound: 1.6 parts by mass

(Product name "Coronate L", manufactured by Nippon Polyurethane Co., Ltd.)

・Photoinitiator: 3 parts by mass

(Product name "Irgacure 184", manufactured by Chiba Specialty Chemicals)

The pressure-sensitive adhesive solution prepared as described above was applied onto the treated surface of a PET release liner treated with silicone, and heated and dried at 120° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 10 μm.

Subsequently, the pressure-sensitive adhesive layer surface and the base material layer (EVA film (115 μm thickness) manufactured by Gunze Co., Ltd.) were bonded together, and stored at 23° C. for 72 hours to prepare a dicing tape.

<Production of die-bonding sheet (thermosetting resin sheet)>

(Example 1)

An epoxy group-containing acrylic polymer (mass average molecular weight Mw = 130,000) was polymerized with the following monomer composition.

Glycidyl methacrylate (GMA): 32% by mass

Ethyl acrylate (EA): 32% by mass

- Butyl methacrylate (BMA): 36% by mass

With respect to 100 parts by mass of the epoxy group-containing acrylic polymer polymerized in the above composition,

Phenol resin: 11 parts by mass (hydroxyl equivalent 203 [g/eq])

(Product name "MEHC-7851H" biphenyl aralkyl type resin phenolic resin manufactured by Meiwa Kasei Co., Ltd.),

・Silica filler: 23 parts by mass (specific surface area 200 [m 2 / g])

(Product name "MEK-ST-40" manufactured by Nissan Kagaku)

And methyl ethyl ketone was mixed, and the adhesive composition solution was prepared so that solid content concentration might become 20 mass %.

The prepared adhesive composition solution was applied as a release liner (separator) onto a release treatment film made of a polyethylene terephthalate film having a thickness of 50 μm subjected to silicone release treatment. Thereafter, a die-bonding sheet having a thickness (average thickness) of 20 μm was produced by performing a drying treatment at 130° C. for 2 minutes.

(Example 2)

An epoxy group-containing acrylic polymer (mass average molecular weight Mw = 40,000) was polymerized with the following monomer composition.

Glycidyl methacrylate (GMA): 40% by mass

Ethyl acrylate (EA): 28% by mass

- Butyl methacrylate (BMA): 32% by mass

With respect to 100 parts by mass of the epoxy group-containing acrylic polymer polymerized with the above composition,

・Silica filler: 42 parts by mass (specific surface area 200 [m 2 / g])

(Product name "MEK-ST-40" manufactured by Nissan Chemical Industries)

And methyl ethyl ketone was mixed, and the adhesive composition solution was prepared so that solid content concentration might become 20 mass %.

Further, a die-bonding sheet having a thickness (average thickness) of 20 µm was produced from the adhesive composition solution by the same method as the above method.

(Example 3)

An epoxy group-containing acrylic polymer (mass average molecular weight Mw = 320,000) was polymerized with the following monomer composition.

Glycidyl methacrylate (GMA): 7% by mass

Ethyl acrylate (EA): 48% by mass

- Butyl methacrylate (BMA): 45% by mass

With respect to 100 parts by mass of the epoxy group-containing acrylic polymer polymerized with the above composition,

Phenol resin: 55 parts by mass (hydroxyl equivalent 173 [g/eq])

(Product name "MEHC-7800H" manufactured by Maywa Kasei Co., Ltd. Phenolxylylene resin)

・Silica filler: 42 parts by mass (specific surface area 60 [m 2 / g])

(Product name "MEK-AC-4130Y" manufactured by Nissan Chemical Industries)

And methyl ethyl ketone was mixed, and the adhesive composition solution was prepared so that solid content concentration might become 20 mass %.

Further, a die-bonding sheet having a thickness (average thickness) of 20 µm was produced from the adhesive composition solution by the same method as the above method.

(Example 4)

An epoxy group-containing acrylic polymer (mass average molecular weight Mw = 320,000) was polymerized with the following monomer composition.

Glycidyl methacrylate (GMA): 7% by mass

Ethyl acrylate (EA): 48% by mass

- Butyl methacrylate (BMA): 45% by mass

Separately, a carboxy group-containing acrylic polymer (mass average molecular weight Mw = 30,000) was polymerized with the following monomer composition.

・Acrylic acid (AA): 1% by mass

- Butyl acrylate (BA): 32% by mass

Ethyl acrylate (EA): 23% by mass

・Methyl methacrylate (MMA): 44% by mass

With respect to 100 parts by mass of the epoxy group-containing acrylic polymer polymerized with the above composition,

Carboxy group-containing acrylic polymer polymerized with the above composition: 64 parts by mass,

And methyl ethyl ketone was mixed, and the adhesive composition solution was prepared so that solid content concentration might become 20 mass %.

Further, a die-bonding sheet having a thickness (average thickness) of 20 µm was produced from the adhesive composition solution by the same method as the above method.

(Comparative Example 1)

・Acrylic resin: 100 parts by mass (containing OH group, mass average molecular weight Mw = 450,000)

(Product name "W248" made by Negami Kogyo)

Phenolic resin: 77 parts by mass (hydroxyl equivalent 105 [g/eq])

(Product name "MEHC-7500" manufactured by Maywa Kasei Co., Ltd.)

・Epoxy resin: 83 parts by mass

(Product name "EPPN501HY" manufactured by Nippon Kayaku Co., Ltd.)

・Silica filler: 222 parts by mass (converted to solid content) (specific surface area 34 [m 2 / g])

(Product name "MEK-AC-5140Z" manufactured by Nissan Chemical Industries)

was mixed with methyl ethyl ketone to prepare an adhesive composition solution so that the solid concentration was 20% by mass.

Further, a die-bonding sheet having a thickness (average thickness) of 20 µm was produced from the adhesive composition solution by the same method as the above method.

(Comparative Example 2)

・Acrylic resin: 100 parts by mass (containing OH group, mass average molecular weight Mw = 450,000)

(Product name "W248" made by Negami Kogyo)

Phenol resin: 279 parts by mass (hydroxyl equivalent 105 [g/eq])

(Product name "MEHC-7500" manufactured by Maywa Kasei Co., Ltd.)

・Epoxy resin: 287 parts by mass

(Product name "EPPN501HY" manufactured by Nippon Kayaku Co., Ltd.)

・Silica filler: 470 parts by mass (converted to solid content) (specific surface area 5 [m 2 / g])

(product name "SO-25R" made by Admatex),

was mixed with methyl ethyl ketone to prepare an adhesive composition solution so that the solid concentration was 20% by mass.

Further, a die-bonding sheet having a thickness (average thickness) of 20 µm was produced from the adhesive composition solution by the same method as the above method.

<Manufacture of dicing die-bonding film>

A dicing die-bonding film was produced by bonding the die-bonding sheets of each example and each comparative example onto the pressure-sensitive adhesive layer of the dicing tape using a hand roller.

<Measurement of physical properties of die-bonding sheet>

For the die-bonding sheets of each Example and each Comparative Example, each physical property was measured as follows.

(Shear loss modulus G")

The details of the method for measuring the shear loss modulus G" described above are as follows. A viscoelasticity measuring device (manufactured by Rheometric Scientific, type ARES) was used as the measuring device. It was punched out into a cylinder shape with a diameter of 7.5 mm and a thickness of 1 mm to form a die bond. A test piece of sheet was produced.When a shear vibration with a frequency of 1 Hz was applied to one circular surface of the test piece at a temperature of 140 ° C, the shear vibration transmitted to the other circular surface was measured. By analyzing the measured value, shear loss Elastic modulus G" was obtained. Table 1 shows the measurement results.

(Measurement of tensile modulus at 150°C, glass transition point Tg, Tanδ at Tg)

After subjecting the die-bonding sheet to a curing treatment at 150°C for 1 hour, the tensile storage modulus of the die-bonding sheet at 150°C was measured. As a measuring device, a solid-state viscoelasticity measuring device (model RSAIII, manufactured by Rheometric Scientific Co., Ltd.) was used.

A test piece with a length of 40 mm (measurement length) and a width of 10 mm is cut out, and under the conditions of a frequency of 1 Hz, a heating rate of 10° C./min, and a distance between chucks of 22.5 mm, the tensile storage modulus E' of the test piece in the temperature range of -30 to 280° C. , tensile loss elastic modulus E" was measured. In addition, Tan δ (E"/E') based on these elastic moduli was measured. In addition, the temperature when Tan δ reached a peak value was read.

(break elongation)

A test piece (width 10 mm x length 40 mm) was cut out of the die-bonding sheet. A tensile test was conducted using a tensile tester (trade name "Autograph AGS-50NX", manufactured by Shimadzu Corporation), and the elongation at break of the test piece elongated at a predetermined tensile speed was measured. The initial distance between chucks was 10 mm, the temperature condition was 0° C., and the tensile speed was 300 mm/min. Table 1 shows the measurement results.

Table 1 shows the composition and physical properties of the die-bonding sheet in each Example and each Comparative Example.

The performance of the die-bonding sheet (dicing die-bonding film) prepared as described above was evaluated as follows.

(Embedding of the die-bonding sheet to the concave portion of the surface of the adherend)

Using a die bonder (manufactured by Shinkawa, product name "Die Bonder SPA-300"), a mirror chip provided with a 10 mm x 10 mm die-bonding sheet was placed on a BGA substrate having 10 µm irregularities on the surface, at a stage temperature of 140°C. , Bonding was performed under conditions of a die-bonding load of 0.2 MPa and a die-bonding time of 2 seconds.

A void between the die-bonding sheet and the substrate (adhered body) was observed using an ultrasonic imaging device (“FS200II” manufactured by Hitachi Finetech Co., Ltd.). The area occupied by the voids in the observation image was calculated using binary software (WinRoof ver.5.6). A case where the area occupied by the voids was less than 10% relative to the surface area of the die-bonding film was evaluated as "○" (good), and a case where it was 10% or more was evaluated as "x" (poor).

(Amount of warpage of die-bonding sheet after heat curing treatment)

Using a die bonder (manufactured by Shinkawa, product name “Die Bonder SPA-300”), a 50 mm × 50 mm size, 160 μm thick BGA substrate with a 10 mm × 10 mm die-bonding sheet is attached to the mirror chip (9 chips). , Bonding was performed under the conditions of a stage temperature of 140°C, a die-bonding load of 0.2 MPa, and a die-bonding time of 2 seconds, with equal intervals between adjacent ones.

The substrate (adherent) after heat treatment at 150°C for 1 hour was placed on a flat plate, and the longest separation distance of the substrate (adherent) separated from the flat plate was measured. A case where the evaluation result was very good was judged as "◎", a good case as "○", and a bad case as "×".

As understood from the above evaluation results, the dicing die-bonding film provided with the die-bonding sheet of the examples was better than the dicing die-bonding film of the comparative example in terms of the embedding property of the die-bonding sheet during die-bonding. . In addition, the amount of warping of the die-bonding sheet accompanying the thermal curing treatment could be suppressed.

The die-bonding sheet of Example contains a crosslinkable acrylic polymer, has a shear loss elastic modulus G" at 140°C of 1 kPa or more and 20 kPa or less before thermal curing, and after thermal curing at 150°C for 1 hour. The tensile modulus of elasticity at 150 ° C. is 0.5 MPa or more and 7.0 MPa or less.

By using the die-bonding sheet (dicing die-bonding film) of the examples having these physical properties in manufacturing a semiconductor device, for example, a so-called NAND type flash memory or the like can be efficiently manufactured.

Specifically, since the shear loss elastic modulus G" of the die-bonding sheet, like the embodiment used for embedding semiconductor chips, is within a specific range, when adhering to the surface of an adherend having irregularities, it is appropriate to embed concave portions. It can be deformed to follow the concavo-convex shape, thereby suppressing the occurrence of gaps between the adherend and the die-bonding sheet.

In addition, a thin semiconductor chip having an electronic circuit formed on one surface may be deformed (bending, etc.) due to internal stress as the die-bonding sheet is cured. On the other hand, since the die-bonding sheet of the examples has a tensile modulus of elasticity after the thermosetting treatment within a specific range, such deformation of the semiconductor chip can be suppressed.

The thermosetting resin sheet (die-bonding sheet) and dicing die-bonding film of the present invention are suitably used, for example, as auxiliary tools when manufacturing a semiconductor device.

1: dicing die-bonding film,
10: thermosetting resin sheet (die-bonding sheet),
20: dicing tape,
21: base layer,
22: adhesive layer.

Claims (11)

In a method for manufacturing a semiconductor device, a thermosetting resin sheet used as a die-bonding sheet for bonding a chip to an adherend by placing a wafer having a circuit surface formed thereon between a chip and an adherend,
A crosslinkable acrylic polymer having a crosslinkable group in its molecule that causes a crosslinking reaction by heat curing treatment,
The shear loss modulus G" at 140 ° C. before the thermal curing treatment is 1 kPa or more and 20 kPa or less, and the tensile modulus at 150 ° C. after the thermal curing treatment for 1 hour at 150 ° C. is 0.5 MPa or more and 7.0 MPa or less. Thermosetting resin sheet. The thermosetting resin sheet according to claim 1, wherein a content ratio of the crosslinkable acrylic polymer to 100 parts by mass of the organic component contained in the die-bonding sheet is 50 parts by mass or more and 100 parts by mass or less. The method according to claim 1 or 2, wherein the glass transition point Tg after the thermal curing treatment at 150 ° C. for 1 hour is 20 ° C. or more and 100 ° C. or less, and the Tan δ at the glass transition point Tg is 0.7 or more and 1.5 or less. Thermosetting resin sheet. The method of claim 1 or 2, wherein the crosslinkable group contains an epoxy group,
The crosslinkable acrylic polymer has a structural unit of glycidyl (meth)acrylate having an epoxy group in a molecule,
The thermosetting type resin sheet in which the content rate of the said structural unit in the said crosslinkable acrylic polymer is 5 mass % or more and 50 mass % or less. The content rate of the silica filler as an inorganic filler is 40 mass % or less of Claim 1 or 2,
The thermosetting type resin sheet whose specific surface area of the said silica filler is 35 m2/g or more and 400 m2/g or less. The method according to claim 1 or 2, comprising a phenol resin that crosslinks with the crosslinkable group by the heat curing treatment,
The thermosetting type resin sheet whose hydroxyl equivalent of the said phenol resin is 160 or more. The thermosetting resin sheet according to claim 1 or 2, which contains one or more kinds of the crosslinkable acrylic polymer, and the mass average molecular weight of at least one kind of the crosslinkable acrylic polymer is 10,000 or more and 400,000 or less. . The thermosetting type resin sheet according to claim 1 or 2, which is used by bonding with a dicing tape. The thermosetting resin sheet according to claim 1 or 2, wherein the elongation at break at 0°C is 50% or less. The thermosetting resin sheet according to claim 1 or 2, which is used in a Stealth Dicing Before Grinding (SDBG) process or a Dicing Before Grinding (DBG) process for manufacturing semiconductor chips by cutting a semiconductor wafer. A dicing die-bonding film comprising a die-bonding sheet composed of the thermosetting resin sheet according to claim 1 or 2, and a dicing tape bonded to the die-bonding sheet.

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