JP7136200B2 - Semiconductor device, thermosetting resin composition and dicing die bonding integrated tape used for its manufacture - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a semiconductor device, and a thermosetting resin composition and a dicing-die-bonding integrated tape used for manufacturing the semiconductor device.

2. Description of the Related Art As devices such as mobile phones have become multi-functional, stacked MCPs (Multi Chip Packages), which have increased capacity by stacking semiconductor elements in multiple stages, have become popular. Film adhesives are widely used for mounting semiconductor elements. A wire-embedded package is an example of a multi-layered package using a film-like adhesive. This package is manufactured through a process of embedding the semiconductor element and wires in the film-like adhesive by pressing the film-like adhesive against the wire-bonded semiconductor element on the substrate.

One of the important characteristics required for semiconductor devices such as the stacked MCP is connection reliability. In order to improve connection reliability, film adhesives are being developed in consideration of properties such as heat resistance, moisture resistance and reflow resistance. For example, Patent Document 1 discloses an adhesive sheet with a thickness of 10-250 μm containing a thermosetting component and a filler. Patent Document 2 discloses an adhesive composition comprising a mixture comprising an epoxy resin and a phenolic resin and an acrylic copolymer.

The connection reliability of the semiconductor device is greatly affected by whether or not the semiconductor element can be mounted without generating voids on the bonding surface. For this reason, a film-like adhesive with high fluidity is used so that the semiconductor element can be pressure-bonded without generating voids, or a film adhesive with a low melt viscosity is used so that the generated voids can be eliminated in the sealing process of the semiconductor element. Ingenuity such as using a film-like adhesive has been made. For example, Patent Document 3 discloses an adhesive sheet with low viscosity and low tack strength.

International Publication No. 2005/103180 JP-A-2002-220576 JP 2009-120830 A

The adhesive sheets of Patent Literatures 1 and 3 contain a relatively large amount of epoxy resin for the purpose of high fluidity in order to embed the wire at the time of crimping. For this reason, thermal curing is likely to proceed due to heat generated during the manufacturing process of the semiconductor device. As a result, the adhesive film becomes highly elastic, in other words, the adhesive sheet is less likely to deform even under high temperature and high pressure conditions during sealing, and the voids formed during pressure bonding may not eventually disappear. On the other hand, since the adhesive composition of Patent Document 2 has a low elastic modulus, it is possible to eliminate voids in the sealing process, but due to its high viscosity, it is difficult to embed the wire during crimping. likely to be sufficient.

2. Description of the Related Art In recent years, increasing the operation speed of wire-embedded semiconductor devices has been emphasized. Conventionally, a controller chip for controlling the operation of a semiconductor device has been arranged on the uppermost layer of stacked semiconductor elements. In order to realize high-speed operation, a semiconductor device package technology has been developed in which a controller chip is arranged at the bottom. As one form of such a package, a relatively thick film-like adhesive is used when pressure-bonding the semiconductor element in the second layer among the semiconductor elements stacked in multiple layers, and the controller is placed inside the film-like adhesive. Packages that embed chips are attracting attention. The film-like adhesive used for such applications is required to have high fluidity so as to be able to fill in the wires connecting the controller chip and the circuit pattern, as well as the unevenness of the substrate surface. This problem can be solved by using a high-fluidity adhesive sheet such as the adhesive sheets of US Pat.

However, while the adhesive sheets described in Patent Documents 1 and 3 exhibit high fluidity before curing, the resin that has flowed when the controller chip is embedded may contaminate the surrounding circuits. In addition, the adhesive sheet flows due to heat curing after embedding, causing the position of the chip to shift, and the resin to enter the inside of the chip from the end face of the embedded chip, causing the resin to disappear from the end of the chip. ” occurs (see FIG. 8). In recent years, in particular, in order to improve the embedding property, heat curing treatment is often performed under pressure conditions. When heat is applied in such a state that pressure is applied from the outside, the embedding property is improved, but the resin is more likely to flow, which often causes the above-described problems.

An object of the present disclosure is to provide a semiconductor device having excellent connection reliability. Another object of the present disclosure is to provide a thermosetting resin composition useful for manufacturing a semiconductor device having excellent connection reliability and a dicing and die bonding integrated tape comprising an adhesive layer comprising the composition.

In order to develop a package in which a controller chip is embedded in a cured film adhesive, the present inventors have extensively researched the selection of the resin of the film adhesive and the adjustment of physical properties. As a result, the present inventors found that the melt viscosity of the film-like adhesive correlates with circuit contamination at the time of embedding and sink marks that occur in the subsequent heating process.

A semiconductor device according to the present disclosure includes a substrate, a first semiconductor element arranged on the substrate, and a region of the substrate where the first semiconductor element is arranged. and a first sealing layer that is arranged to cover the surface of the first sealing layer opposite to the substrate side, and has an area larger than that of the first semiconductor element 2 semiconductor element, the first sealing layer is made of a cured product of a thermosetting resin composition, and the melt viscosity of the thermosetting resin composition at 120° C. is 2500 to 11500 Pa·s.

The above-described semiconductor device has a mode in which the first semiconductor element (for example, a controller chip) is embedded in the cured product of the thermosetting resin composition, and can operate at high speed. The first sealing layer is a cured product of a thermosetting resin composition having a melt viscosity at 120 ° C. of 2500 to 11500 Pa s, so that the gap at the interface with the substrate or the first semiconductor element is sufficient. In addition, the problem of substrate contamination and sink marks is sufficiently suppressed, so that excellent connection reliability between the substrate and the first semiconductor element can be achieved.

The semiconductor device according to the present disclosure may further include a circuit pattern formed on the surface of the substrate, and first wires electrically connecting the first semiconductor element and the circuit pattern. A semiconductor device according to the present disclosure includes a second wire that electrically connects a second semiconductor element and a circuit pattern, and a second sealing that seals the second semiconductor element and the second wire. and a layer. The semiconductor device according to the present disclosure may further include a third semiconductor element laminated on the second semiconductor element.

The thermosetting resin composition constituting the film-like adhesive contains a low molecular weight component (eg, epoxy resin) with a molecular weight of 10 to 1,000 and a high molecular weight component (eg, acrylic rubber) with a molecular weight of 100,000 to 1,000,000. The content M1 of the low molecular weight component is 23 to 35 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition, and the content M2 of the high molecular weight component is a thermosetting resin It is preferably 25 to 45 parts by mass with respect to 100 parts by mass of the resin component contained in the composition. By using a thermosetting resin composition having such a composition, the low molecular weight component contributes to excellent embedding properties, while the high molecular weight component contributes to suppression of problems caused by excessive flow. In the thermosetting resin composition, the total amount (M1+M2) of the low molecular weight component and the high molecular weight component is 54 to 76 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition. is preferred.

The molecular weight (weight average molecular weight) of the resin component contained in the thermosetting resin composition means a value measured by gel permeation chromatography (GPC) and converted using a standard polystyrene calibration curve.

When using a substrate having a circuit pattern on its surface, the semiconductor device according to the present disclosure further includes a first wire electrically connecting the first semiconductor element and the circuit pattern. Alternatively, a second wire electrically connecting the second semiconductor element and the circuit pattern, and a second sealing layer sealing the second semiconductor element and the second wire are further provided. It may be provided.

In the thermosetting resin composition according to the present disclosure, at least a part of the wire and at least one of the semiconductor elements are subjected to a curing treatment of heating the thermosetting resin composition, and the thermosetting resin composition after the curing treatment. It is used in the manufacturing process of a semiconductor device including a step of embedding, and the melt viscosity of the thermosetting resin composition at 120° C. is 2500 to 11500 Pa·s. According to the thermosetting resin composition, it has a fluidity that allows embedding of a semiconductor element or the like, and contamination of the peripheral circuit at the time of embedding and the subsequent heating process (thermosetting treatment of the thermosetting resin composition). can sufficiently suppress problems caused by excessive flow of

A dicing die bonding integrated tape according to the present disclosure includes an adhesive layer and an adhesive layer made of the thermosetting resin composition.

According to the present disclosure, a semiconductor device having excellent connection reliability is provided, and a thermosetting resin composition used in its manufacture and an integrated dicing and die bonding tape comprising an adhesive layer composed of it are provided. . This thermosetting resin composition has excellent embeddability capable of embedding at least one of a semiconductor element such as a controller chip and a wire, and prevents contamination of peripheral circuits during embedding and excess resin in subsequent thermal processes. Problems caused by flow can be sufficiently suppressed.

FIG. 1 is a cross-sectional view schematically showing an example of a semiconductor device. FIG. 2 is a cross-sectional view schematically showing an example of a laminate composed of a film-like adhesive and a second semiconductor element. 3A to 3C are cross-sectional views schematically showing the process of manufacturing the semiconductor device shown in FIG. 4A to 4D are cross-sectional views schematically showing the process of manufacturing the semiconductor device shown in FIG. 5A to 5D are cross-sectional views schematically showing the process of manufacturing the semiconductor device shown in FIG. 6A to 6C are cross-sectional views schematically showing the process of manufacturing the semiconductor device shown in FIG. 7(a) to 7(e) are cross-sectional views schematically showing the process of manufacturing a laminate comprising a film-like adhesive and a second semiconductor element. FIG. 8(a) is a photograph showing a cross section of a structure in which a phenomenon called "sink marks" does not occur, and FIG. ) is a photograph showing a cross section. FIG. 9(a) is a cross-sectional view schematically showing a structure for evaluating the presence or absence of voids, and FIG. 9(b) is a photograph of the structure without voids. c) is a photograph of a voided structure.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and overlapping descriptions are omitted. In addition, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to the illustrated ratios. In addition, the description of "(meth)acryl" in this specification means "acryl" and "methacryl" corresponding to it.

<Semiconductor device>
FIG. 1 is a cross-sectional view schematically showing a semiconductor device according to this embodiment. The semiconductor device 100 shown in this figure includes a substrate 10, a first semiconductor element Wa arranged on the surface of the substrate 10, and a first sealing layer 20 sealing the first semiconductor element Wa. , a second semiconductor element Wb disposed above the first semiconductor element Wa, and a second sealing layer 40 sealing the second semiconductor element Wb.

The substrate 10 has circuit patterns 10a and 10b on its surface. From the viewpoint of suppressing warping of the semiconductor device 100, the thickness of the substrate 10 is, for example, 90 to 180 μm, and may be 90 to 140 μm. The substrate 10 may be an organic substrate or a metal substrate such as a lead frame.

In this embodiment, the first semiconductor element Wa is a controller chip for driving the semiconductor device 100 . The first semiconductor element Wa is adhered onto the circuit pattern 10a via an adhesive 15, and is connected via the first wire 11 to the circuit pattern 10b. The shape of the first semiconductor element Wa in plan view is, for example, a rectangle (square or rectangle). The length of one side of the first semiconductor element Wa is, for example, 5 mm or less, and may be 2 to 4 mm or 1 to 4 mm. The thickness of the first semiconductor element Wa is, for example, 10 to 150 μm, and may be 20 to 100 μm.

The second semiconductor element Wb has a larger area than the first semiconductor element Wa. The second semiconductor element Wb is mounted on the substrate 10 via the first sealing layer 20 so as to cover the entire first semiconductor element Wa and part of the circuit pattern 10b. The shape of the second semiconductor element Wb in plan view is, for example, a rectangle (square or rectangle). The length of one side of the second semiconductor element Wb is, for example, 20 mm or less, and may be 4 to 20 mm or 4 to 12 mm. The thickness of the second semiconductor element Wb is, for example, 10-170 μm, and may be 20-120 μm. The second semiconductor element Wb is connected to the circuit pattern 10b via the second wire 12 and sealed with the sealing layer 25 .

The first sealing layer 20 is made of a cured film adhesive 20P (see FIG. 2). Incidentally, as shown in FIG. 2, the film adhesive 20P and the second semiconductor element Wb have substantially the same size. A laminate 30 shown in FIG. 2 is composed of a film adhesive 20P and a second semiconductor element Wb, and is also referred to as a semiconductor chip with adhesive. The laminate 30 is produced through a dicing process and a pick-up process, as described later (see FIG. 7).

<Method for manufacturing a semiconductor device>
A method for manufacturing the semiconductor device 100 will be described. First, the structure 50 shown in FIG. 3 is produced. That is, the first semiconductor element Wa is arranged on the surface of the substrate 10 with the adhesive 15 interposed therebetween. After that, the first semiconductor element Wa and the circuit pattern 10b are electrically connected with the first wire 11. Next, as shown in FIG.

Next, as shown in FIGS. 3 and 4, the film adhesive 20P of the laminate 30 prepared separately is pressed against the substrate 10. Next, as shown in FIGS. As a result, the first semiconductor element Wa and the first wires 11 are embedded in the film adhesive 20P. The thickness of the film-like adhesive 20P may be appropriately set according to the thickness of the first semiconductor element Wa, etc. For example, the thickness may be in the range of 20 to 200 μm, such as 30 to 200 μm or 40 to 150 μm. may By setting the thickness of the film-like adhesive 20P within the above range, it is possible to secure a sufficient distance (distance G in FIG. 5) between the first semiconductor element Wa and the second semiconductor element Wb. The distance G is, for example, preferably 50 μm or more, and may be 50-75 μm or 50-80 μm.

The pressure bonding of the film adhesive 20P to the substrate 10 is preferably performed, for example, under conditions of 80 to 180° C. and 0.01 to 0.50 MPa for 0.5 to 3.0 seconds.

Next, the film adhesive 20P is cured by heating. This curing treatment is preferably carried out, for example, under conditions of 60 to 175° C. and 0.01 to 1.0 MPa for 5 minutes or longer. As a result, the first semiconductor element Wa is sealed with the cured film adhesive 20P (first sealing layer 20) (see FIG. 6). The curing treatment of the film adhesive 20P may be performed under a pressurized atmosphere from the viewpoint of reducing voids. After electrically connecting the second semiconductor element Wb and the circuit pattern 10b with the second wire 12, the second semiconductor element Wb is sealed with the second sealing layer 40 to complete the semiconductor device 100. (see Figure 1).

<Method for producing semiconductor chip with adhesive>
An example of a method for manufacturing the laminate 30 (semiconductor chip with adhesive) shown in FIG. 2 will be described with reference to FIGS. 7(a) to 7(e). First, a dicing die bonding integrated tape 8 (hereinafter sometimes referred to as "tape 8") is arranged in a predetermined device (not shown). The tape 8 comprises a base material layer 1, an adhesive layer 2 and an adhesive layer 20A in this order. The base material layer 1 is, for example, a polyethylene terephthalate film (PET film). The semiconductor wafer W is, for example, a thin semiconductor wafer with a thickness of 10-100 μm. The semiconductor wafer W may be monocrystalline silicon, polycrystalline silicon, various ceramics, or compound semiconductors such as gallium arsenide.

As shown in FIGS. 7A and 7B, the tape 8 is attached to one surface of the semiconductor wafer W so that the adhesive layer 20A is in contact therewith. This step is preferably carried out at a temperature of 50-100°C, more preferably 60-80°C. When the temperature is 50° C. or higher, good adhesion between the semiconductor wafer W and the adhesive layer 20A can be obtained. be.

As shown in FIG. 7C, the semiconductor wafer W, adhesive layer 2 and adhesive layer 20A are diced. As a result, the semiconductor wafer W is separated into individual semiconductor elements Wb. The adhesive layer 20A is also singulated to form a film adhesive 20P. A dicing method includes a method using a rotary blade or a laser. In addition, the semiconductor wafer W may be thinned by grinding the semiconductor wafer W prior to the dicing of the semiconductor wafer W. FIG.

Next, when the adhesive layer 2 is, for example, a UV curable type, as shown in FIG. It reduces the adhesive strength with the adhesive 20P. After the ultraviolet irradiation, as shown in FIG. 7(e), the semiconductor elements Wa are separated from each other by expanding the base layer 1 under room temperature or cooling conditions, and the semiconductor elements Wa are pushed up with needles 42 to be laminated from the adhesive layer 2. The film adhesive 20P of the body 30 is peeled off, and the laminate 30 is sucked by the suction collet 44 and picked up. The laminate 30 thus obtained is used for manufacturing the structure 50 shown in FIG.

<Thermosetting resin composition>
The thermosetting resin composition that constitutes the film adhesive 20P will be described. The film-like adhesive 20P is obtained by dividing the adhesive layer 20A into individual pieces, and both are made of the same thermosetting resin composition. This thermosetting resin composition can, for example, go through a semi-cured (B stage) state and then become a fully cured (C stage) state by a subsequent curing treatment.

The thermosetting resin composition preferably contains the following components.
(a) Thermosetting resin (hereinafter sometimes simply referred to as "(a) component")
(b) high molecular weight component (hereinafter sometimes simply referred to as "(b) component")
(c) Inorganic filler (hereinafter sometimes simply referred to as "(c) component")
In the present embodiment, when (a) the thermosetting resin contains an epoxy resin, the epoxy resin (hereinafter sometimes simply referred to as "(a1) component") corresponds to the "low molecular weight component". In this case, (a) the thermosetting resin preferably contains a phenolic resin (hereinafter sometimes simply referred to as "(a2) component") that can serve as a curing agent for epoxy resins.

The thermosetting resin composition may further contain the following components.
(d) Coupling agent (hereinafter sometimes simply referred to as "(d) component")
(e) curing accelerator (hereinafter sometimes simply referred to as "(e) component")

The thermosetting resin composition preferably contains both a low molecular weight component (component (a1)) having a molecular weight of 10 to 1,000 and a high molecular weight component (component (b)) having a molecular weight of 100,000 to 1,000,000. By using these components together, the low molecular weight component contributes to excellent embeddability, while the high molecular weight component contributes to suppression of problems caused by excessive flow.

The content M1 of the low molecular weight component is preferably 23 to 35 parts by mass, more preferably 25 to 35 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition. . When the content M1 of the low-molecular-weight component is 23 parts by mass or more, excellent embedding properties can be easily achieved, while when it is 35 parts by mass or less, excellent pick-up properties can be easily achieved. be done. The softening point of the low-molecular-weight component is preferably 50°C or less, and may be, for example, 10 to 30°C.

The content M2 of the high molecular weight component is preferably 25 to 45 parts by mass, more preferably 30 to 40 parts by mass, with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition. . When the content M2 of the high-molecular-weight component is 25 parts by mass or more, problems caused by excessive flow (substrate contamination, sink marks, warping, etc.) can be easily suppressed. The effect of easily achieving excellent embeddability is exhibited. The softening point of the high molecular weight component is preferably above 50°C and 100°C or less.

The total amount of the low molecular weight component and the high molecular weight component (M1+M2) is preferably 54 to 76 parts by weight, preferably 55 to 75 parts by weight, with respect to 100 parts by weight of the resin component contained in the thermosetting resin composition. It is more preferable to have When the total amount is 54 parts by mass or more, the effect of the combined use of these components tends to be sufficiently exhibited, while when the total amount is 76 parts by mass or less, excellent pickup properties are achieved. It has the effect of making it easier. The resin components contained in the thermosetting resin composition other than the low molecular weight component and the high molecular weight component mainly include thermosetting resins having a molecular weight of 1,001 to 99,000.

The melt viscosity of the thermosetting resin composition at 120° C. is 2500 to 11500 Pa·s from the viewpoint of connection reliability. When the melt viscosity is 2500 Pa·s or more, it is possible to sufficiently suppress the problem of contamination and sink marks on the substrate 10 during pressure bonding. For example, if there is a region (sink mark) where the cured product of the thermosetting resin composition does not exist between the second semiconductor element Wb and the substrate 10, the sealing material for the second sealing layer 40 is formed in that region. invades the second semiconductor element Wb, which tends to cause a problem that the second semiconductor element Wb is easily peeled off. When the melt viscosity of the thermosetting resin composition at 120° C. is 11,500 Pa·s or less, voids at the interface with the substrate 10 or the first semiconductor element Wa can be sufficiently reduced. The melt viscosity is preferably 5,000 to 11,000 Pa·s, more preferably 5,000 to 10,000 Pa·s, still more preferably 5,000 to 9,000 Pa·s. The melt viscosity was measured while increasing the temperature at a rate of 5° C./min while giving a strain of 5% to the thermosetting resin composition molded into a film using ARES (manufactured by TA Instruments). Means the measured value of the case.

The melt viscosity at 100° C. of the thermosetting resin composition is preferably 3500 to 13500 Pa·s from the viewpoint of connection reliability. When the melt viscosity is 3500 Pa·s or more, it is possible to sufficiently suppress the occurrence of problems such as contamination of the substrate 10 and sink marks during compression bonding. On the other hand, when the melt viscosity is 13500 Pa·s or less, the voids at the interface with the substrate 10 or the first semiconductor element Wa can be sufficiently reduced. The melt viscosity is preferably 5500 to 10500 Pa·s. In order to make the melt viscosity of the thermosetting resin composition at 100 ° C. and 120 ° C. within the above range, the amounts of (a) thermosetting resin, (b) high molecular weight component and (c) inorganic filler should be appropriately adjusted. Just do it.

FIG. 9A shows a transparent substrate 10, a first semiconductor element Wa thereon, a first sealing layer 20 (hardened film-like adhesive 20P), and a second semiconductor element thereon. Wb. 9(b) and 9(c) are photographs taken from the back side of the transparent substrate 10 (in the direction of the arrow in FIG. 9(a)). In the structure shown in FIG. 9(b), the embedding property of the film-like adhesive is sufficient and voids are not generated. On the other hand, in the structure shown in FIG. 9(c), the embedding property of the film-like adhesive is insufficient, and voids V are generated.

The storage elastic modulus at 180° C. of the cured product (C stage) of the thermosetting resin composition is preferably 10 MPa or higher, more preferably 25 MPa or higher, and 50 MPa or higher or 100 MPa, from the viewpoint of connection reliability. or more. In addition, the upper limit of this storage elastic modulus is, for example, 600 MPa, and may be 500 MPa. The storage elastic modulus at 180°C of the cured product of the thermosetting resin composition can be measured using a dynamic viscoelasticity device using a film adhesive cured at a temperature of 175°C as a sample. can.

<(a) thermosetting resin>
Component (a1) can be used without any particular limitation as long as it has an epoxy group in its molecule. Examples of the component (a1) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin. Epoxy resins, dicyclopentadiene skeleton-containing epoxy resins, stilbene-type epoxy resins, triazine skeleton-containing epoxy resins, fluorene skeleton-containing epoxy resins, triphenolphenolmethane-type epoxy resins, biphenyl-type epoxy resins, xylylene-type epoxy resins, biphenylaralkyl-type epoxy resins Resins, naphthalene-type epoxy resins, polyfunctional phenols, diglycidyl ether compounds of polycyclic aromatics such as anthracene, and the like. You may use these individually by 1 type or in combination of 2 or more types. Among these, the component (a1) may be a cresol novolac type epoxy resin, a bisphenol F type epoxy resin, or a bisphenol A type epoxy resin from the viewpoint of heat resistance.

The epoxy equivalent weight of component (a1) may be 90-300 g/eq, 110-290 g/eq, or 130-280 g/eq. When the epoxy equivalent of the component (a1) is in this range, it tends to be possible to secure fluidity while maintaining the bulk strength of the film-like adhesive.

The content of component (a1) is 5 to 50 parts by mass, 10 to 40 parts by mass, or 20 to 30 parts by mass with respect to 100 parts by mass of the total mass of components (a), (b), and (c). It may be parts by mass. When the content of the component (a1) is 5 parts by mass or more, the embedding property of the film adhesive tends to be better. When the content of component (a1) is 50 parts by mass or less, the occurrence of bleeding tends to be more suppressed.

Component (a2) can be used without any particular limitation as long as it has a phenolic hydroxyl group in the molecule. Component (a2) includes, for example, phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol and aminophenol, and/or naphthols such as α-naphthol, β-naphthol and dihydroxynaphthalene. Phenols such as novolac-type phenolic resins, allylated bisphenol A, allylated bisphenol F, allylated naphthalenediol, phenol novolak, and phenol obtained by condensing or co-condensing a compound having an aldehyde group such as formaldehyde in the presence of an acidic catalyst and/or phenol aralkyl resins and naphthol aralkyl resins synthesized from naphthols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl. You may use these individually by 1 type or in combination of 2 or more types. Among these, the component (a2) may be a phenol aralkyl resin, a naphthol aralkyl resin, or a novolak-type phenol resin from the viewpoint of hygroscopicity and heat resistance.

The hydroxyl equivalent of component (a2) may be 80-250 g/eq, 90-200 g/eq, or 100-180 g/eq. When the hydroxyl equivalent of the component (a2) is in this range, it tends to be possible to maintain a higher adhesive strength while maintaining the fluidity of the film-like adhesive.

The softening point of component (a2) may be 50-140°C, 55-120°C, or 60-100°C.

The content of component (a2) is 5 to 50 parts by mass, 10 to 40 parts by mass, or 20 to 30 parts by mass with respect to 100 parts by mass of the total mass of components (a), (b), and (c). It may be parts by mass. When the content of component (a2) is 5 parts by mass or more, better curability tends to be obtained. When the content of the component (a2) is 50 parts by mass or less, the embedding property of the film adhesive tends to be better.

The ratio of the epoxy equivalent of component (a1) to the hydroxyl equivalent of component (a2) (epoxy equivalent of component (a1)/hydroxy equivalent of component (a2)) is 0.30/0.70 from the viewpoint of curability. ~0.70/0.30, 0.35/0.65~0.65/0.35, 0.40/0.60~0.60/0.40, or 0.45/0.55~ It may be 0.55/0.45. When the corresponding amount ratio is 0.30/0.70 or more, more sufficient curability tends to be obtained. When the corresponding amount ratio is 0.70/0.30 or less, it is possible to prevent the viscosity from becoming too high and obtain more sufficient fluidity.

<(b) High molecular weight component>
Component (b) preferably has a glass transition temperature (Tg) of 50° C. or lower.

Component (b) includes, for example, acrylic resins, polyester resins, polyamide resins, polyimide resins, silicone resins, butadiene resins, acrylonitrile resins and modified products thereof.

The component (b) may contain an acrylic resin from the viewpoint of fluidity. Here, acrylic resin means a polymer containing structural units derived from (meth)acrylic acid ester. The acrylic resin is preferably a polymer containing, as a structural unit, a structural unit derived from a (meth)acrylic acid ester having a crosslinkable functional group such as an epoxy group, an alcoholic or phenolic hydroxyl group, or a carboxyl group. The acrylic resin may also be acrylic rubber such as a copolymer of (meth)acrylic acid ester and acrylonitrile.

The glass transition temperature (Tg) of the acrylic resin may be -50 to 50°C or -30 to 30°C. When the Tg of the acrylic resin is −50° C. or higher, it tends to be possible to prevent the flexibility of the adhesive composition from becoming too high. This makes it easier to cut the film-like adhesive during wafer dicing, making it possible to prevent the occurrence of burrs. When the Tg of the acrylic resin is 50°C or less, it tends to be possible to suppress a decrease in the flexibility of the adhesive composition. This tends to make it easier to sufficiently fill voids when the film-like adhesive is attached to the wafer. Also, it is possible to prevent chipping during dicing due to deterioration in adhesion of the wafer. Here, the glass transition temperature (Tg) means a value measured using a DSC (differential scanning calorimeter) (for example, "Thermo Plus 2" manufactured by Rigaku Corporation).

The acrylic resin may have a weight average molecular weight (Mw) of 100,000 to 3,000,000 or 500,000 to 2,000,000. When the Mw of the acrylic resin is in such a range, the film formability, the strength in the form of a film, the flexibility, the tackiness, etc. can be appropriately controlled, and the reflow property is excellent, and the embedding property is improved. be able to. Here, Mw means a value measured by gel permeation chromatography (GPC) and converted using a standard polystyrene calibration curve.

Examples of commercially available acrylic resins include SG-70L, SG-708-6, WS-023 EK30, SG-280 EK23, HTR-860P-3CSP, HTR-860P-3CSP-3DB (all available from Nagase ChemteX Corporation). manufactured by the company).

The content of component (b) is 5 to 70 parts by mass, 10 to 50 parts by mass, or 15 to 30 parts by mass with respect to 100 parts by mass of the total mass of components (a), (b), and (c). It may be parts by mass. When the content of the component (b) is 5 parts by mass or more, the fluidity control during molding and the handleability at high temperatures can be further improved. If the content of the component (b) is 70 parts by mass or less, the embeddability can be further improved.

<(c) inorganic filler>
Component (c) includes, for example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, and boron nitride. , silica and the like. You may use these individually by 1 type or in combination of 2 or more types. Among these, the component (c) may be silica from the viewpoint of compatibility with the resin.

The average particle diameter of component (c) may be 0.005 to 1 μm or 0.05 to 0.5 μm from the viewpoint of improving adhesiveness. Here, the average particle diameter means a value obtained by converting from the BET specific surface area.

The content of component (c) is 5 to 50 parts by mass, 15 to 45 parts by mass, or 25 to 40 parts by mass with respect to 100 parts by mass of the total mass of components (a), (b), and (c). It may be parts by mass. When the content of component (c) is 5 parts by mass or more, the fluidity of the film adhesive tends to be further improved. When the content of component (c) is 50 parts by mass or less, the dicing property of the film adhesive tends to be better.

<(d) Coupling agent>
(d) Component may be a silane coupling agent. Silane coupling agents include, for example, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, and the like. be done. You may use these individually by 1 type or in combination of 2 or more types.

The content of component (d) may be 0.01 to 5 parts by mass with respect to 100 parts by mass of the total mass of components (a), (b) and (c).

<(e) Curing accelerator>
Component (e) is not particularly limited, and commonly used components can be used. Component (e) includes, for example, imidazoles and their derivatives, organophosphorus compounds, secondary amines, tertiary amines, quaternary ammonium salts and the like. You may use these individually by 1 type or in combination of 2 or more types. Among these, imidazoles and derivatives thereof may be used as component (e) from the viewpoint of reactivity.

Examples of imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole and the like. You may use these individually by 1 type or in combination of 2 or more types.

The content of component (e) may be 0.01 to 1 part by mass per 100 parts by mass of the total mass of components (a), (b) and (c).

[Dicing die bonding integrated tape and its manufacturing method]
The dicing/die bonding integrated tape 8 shown in FIG. 7(a) and its manufacturing method will be described. The method for producing the tape 8 includes the steps of applying a varnish of an adhesive composition containing a solvent onto a base film (not shown), and drying the applied varnish by heating at 50 to 150 ° C. to form an adhesive layer 20A. and forming.

The varnish of the adhesive composition can be prepared, for example, by mixing or kneading components (a) to (c) and, if necessary, components (d) and (e) in a solvent. Mixing or kneading can be carried out by using an ordinary dispersing machine such as a stirrer, a kneading machine, a triple roll, a ball mill, or the like, and by appropriately combining these.

The solvent for preparing the varnish is not limited as long as it can uniformly dissolve, knead or disperse the above components, and conventionally known solvents can be used. Examples of such solvents include ketone-based solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, toluene and xylene. It is preferable to use methyl ethyl ketone, cyclohexanone, etc., because of their high drying speed and low price.

The base film is not particularly limited, and examples thereof include polyester film, polypropylene film (OPP film, etc.), polyethylene terephthalate film, polyimide film, polyetherimide film, polyether naphthalate film, methylpentene film and the like.

As a method for applying the varnish to the substrate film, a known method can be used, and examples thereof include a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, a curtain coating method, and the like. . The conditions for drying by heating are not particularly limited as long as the solvent used is sufficiently volatilized. Heat drying may be carried out by stepwise raising the temperature within the range of 50 to 150°C. By volatilizing the solvent contained in the varnish by heating and drying, a laminated film of the substrate film and the adhesive layer 20A can be obtained.

The tape 8 can be obtained by laminating the laminate film obtained as described above and a dicing tape (laminated body of the base layer 1 and the adhesive layer 2). Examples of the substrate layer 1 include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. Further, the substrate layer 1 may be subjected to surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment, etching treatment, etc., as necessary. The adhesive layer 2 may be UV curable or pressure sensitive. The tape 8 may further include a protective film (not shown) covering the adhesive layer 2 .

Although the embodiments of the present disclosure have been described above in detail, the present invention is not limited to the above embodiments. For example, in the above embodiment, the package in which the two semiconductor elements Wa and Wb are stacked is illustrated, but a third semiconductor element may be stacked above the second semiconductor element Wb, One or more semiconductor elements may be stacked thereon.

EXAMPLES Hereinafter, the present disclosure will be described more specifically with reference to Examples. However, the present invention is not limited to the following examples.

( Reference Example 1, Examples 2 to 5 and Comparative Examples 1 to 3 )
Varnishes ( 8 types in total) containing the components shown in Tables 1 and 2 were prepared as follows. Specifically, cyclohexanone was added to a composition containing an epoxy resin and a phenol resin as thermosetting resins and an inorganic filler, and the mixture was stirred. After adding acrylic rubber as a high-molecular-weight component to this and stirring, a coupling agent and a curing accelerator were further added, and the components were stirred until they were sufficiently uniform to obtain a varnish.

The components listed in Tables 1 and 2 are as follows.
(Epoxy resin)
・ YDF-8170C (trade name): manufactured by Toto Kasei Co., Ltd., bisphenol F type epoxy resin, epoxy equivalent 159, liquid at normal temperature, softening point 10 to 30 ° C., molecular weight 100 to 1000 (low molecular weight component)
・ YDCN-700-10 (trade name): manufactured by Tohto Kasei Co., Ltd., cresol novolac type epoxy resin, epoxy equivalent 210, softening point 75 to 85 ° C.), molecular weight over 1000 (phenolic resin)
・Mirex XLC-LL (trade name): Mitsui Chemicals, Inc., phenolic resin, hydroxyl equivalent 175, softening point 77°C, molecular weight over 1000 (acrylic rubber)
・ HTR-860P-3CSP: manufactured by Nagase ChemteX Co., Ltd., weight average molecular weight 800,000 (high molecular weight component)
(Inorganic filler)
・ SC2050-HLG (trade name): manufactured by Admatechs Co., Ltd., silica filler dispersion, average particle size 0.50 μm
(Curing accelerator)
・Curesol 2PZ-CN (trade name): 1-cyanoethyl-2-phenylimidazole manufactured by Shikoku Chemical Industry Co., Ltd.

The varnish containing the above components was filtered through a 100-mesh filter and vacuum defoamed. The varnish after vacuum defoaming was applied onto a release-treated polyethylene terephthalate (PET) film (thickness: 38 μm). The applied varnish was dried by heating in two steps, 90° C. for 5 minutes and then 140° C. for 5 minutes. In this way, an adhesive sheet comprising a PET film as a base film and a B-stage film-like adhesive (thickness: 60 μm) was obtained.

(Measurement of melt viscosity of film adhesive)
The melt viscosities of film adhesives at 100°C and 120°C were measured by the following method. That is, five sheets of film-like adhesive with a thickness of 60 μm were laminated to obtain a thickness of 300 μm, which was then punched into a size of 10 mm×10 mm to obtain a sample for measurement. A circular aluminum plate jig with a diameter of 8 mm was set in a dynamic viscoelasticity device ARES (manufactured by TA Instruments), and the sample was further set thereon. After that, measurements were taken while the temperature was raised to 130°C at a heating rate of 5°C/min while applying a strain of 5% at 35°C, and the melt viscosity values at 100°C and 120°C were recorded. Tables 1 and 2 show the results.

(Measurement of Elastic Modulus of Cured Film Adhesive)
The elastic modulus at 180° C. of a cured film adhesive (cured under a temperature condition of 175° C.) was measured. For the measurement, a dynamic viscoelasticity device (product name: Rheogel-E4000, manufactured by UBM Co., Ltd.) was used, a tensile load was applied to the sample, and the temperature was increased to 300 ° C. at a frequency of 10 Hz and a heating rate of 3 ° C./min. and measured the elastic modulus at 180°C. Tables 1 and 2 show the results.

<Evaluation of Film Adhesive>
The film adhesive was evaluated on the following items.

[Embedability]
The embedding property of the film adhesive was evaluated by the following method.
(Preparation of Laminate Consisting of First Semiconductor Element and Film Adhesive)
A dicing die bonding integrated film HR-9004-10 (manufactured by Hitachi Chemical Co., Ltd., adhesive layer thickness 10 μm, adhesive layer thickness 110 μm) is attached to a semiconductor wafer (diameter: 8 inches, thickness: 50 μm). rice field. By dicing this, a first laminate comprising a first semiconductor element (controller chip, size: 3.0 mm×3.0 mm) and a film adhesive was obtained.
(Preparation of Laminate Consisting of Second Semiconductor Element and Film Adhesive)
A dicing-die-bonding integrated film was prepared from each of the film-like adhesives (thickness: 120 μm) according to Reference Examples, Examples, and Comparative Examples, and an adhesive film for dicing. This was attached to a semiconductor wafer (diameter: 8 inches, thickness: 30 μm). By dicing this, a second laminate comprising a second semiconductor element (size: 7.5 mm×7.5 mm) and a film adhesive was obtained.
(Adhesion of first and second semiconductor elements)
A substrate (surface unevenness: maximum 6 μm) was prepared for pressure bonding of the first and second semiconductor elements. After pressing the first semiconductor element to this substrate via the film adhesive under conditions of 120° C., 0.20 MPa, and 2 seconds, the film adhesive is semi-cured by heating at 120° C. for 2 hours. let me
Next, the second semiconductor element was crimped under the conditions of 120° C., 0.20 MPa, and 2 seconds via the film-like adhesive to be evaluated so as to cover the first semiconductor element. At this time, alignment was performed so that the center positions of the first semiconductor element and the second semiconductor element, which had been pressure-bonded earlier, were aligned in a plan view.
The structure obtained as described above was placed in a pressure oven, heated from 35° C. to 140° C. at a rate of 3° C./min, and heated at 140° C. for 30 minutes. The embeddability was confirmed by analyzing the heat-treated structure with an ultrasonic imaging device SAT (manufactured by Hitachi Power Solutions Co., Ltd., product number FS200II, probe: 25 MHz). Evaluation was performed according to the following criteria. Tables 3 and 4 show the results.
A: The area ratio of voids in a given cross section is less than 5%.
B: The area ratio of voids in a predetermined cross section is 5% or more.

[Presence or absence of package contamination and sink marks]
The presence or absence of contamination and the occurrence of sink marks were confirmed by observing the top and side surfaces of the structure subjected to embedding evaluation under a microscope. For the sample with sink marks, the depth of the sink marks (starting point: edge of the second semiconductor element) was measured. Tables 3 and 4 show the results.

[Measurement of adhesive strength]
The die shear strength (adhesive strength) of the cured film adhesive was measured by the following method. First, each film adhesive (120 μm thick) according to Reference Example, Example and Comparative Example was attached to a semiconductor wafer (400 μm thick) at 70°C. By dicing this, a laminate consisting of a semiconductor element (size: 5 mm×5 mm) and a film-like adhesive was obtained. On the other hand, a substrate having a surface coated with a solder resist ink (AUS308) was prepared. A semiconductor element was press-bonded to this surface via a film-like adhesive under conditions of 120° C., 0.1 MPa, and 5 seconds. After that, this was heat-treated at 110° C. for 1 hour, and further heated at 170° C. for 3 hours to cure the film-like adhesive, thereby obtaining a sample for measurement. This sample was left for 168 hours under conditions of 85° C. and 60 RH%. After that, the sample was allowed to stand under conditions of 25° C. and 50% RH for 30 minutes, and then the die shear strength was measured at 250° C., which was defined as the adhesive strength. A Universal Bond Tester Series 4000 manufactured by Dage was used to measure the die shear strength. Tables 3 and 4 show the results.

[Evaluation of reflow resistance]
The reflow resistance of the film adhesive was evaluated by the following method. First, a structure similar to the structure used for embedding evaluation was produced. A package for evaluation was obtained by encapsulating the second semiconductor element of the structure with a molding encapsulant (manufactured by Hitachi Chemical Co., Ltd., trade name “CEL-9750ZHF10”). The conditions were 175° C./6.7 MPa/90 seconds, and the curing conditions were 175° C. and 5 hours.
Twenty-four of the above packages were prepared and exposed to the environment specified by JEDEC (level 3, 30°C, 60 RH%, 192 hours) to absorb moisture. Subsequently, the moisture-absorbed package was passed through an IR reflow oven (260° C., maximum temperature 265° C.) three times. Evaluation was performed according to the following criteria. Tables 3 and 4 show the results.
A: None of the 24 packages showed damage, change in thickness, peeling at the interface between the film-like adhesive and the semiconductor element, and the like.
B: Breakage of the package, change in thickness, peeling at the interface between the film-like adhesive and the semiconductor element, etc. were observed in at least one of the 24 packages.

As is clear from the results shown in Tables 3 and 4, the film-like adhesives of Reference Example 1 and Examples 2 to 5 were compared to the film-like adhesives of Comparative Examples 1 to 3, and the pressure oven After the treatment, it was confirmed that the embedding property was excellent and the occurrence of package contamination and sink marks could be suppressed.

According to the present disclosure, while having the fluidity to embed at least one of a semiconductor element such as a controller chip and a wire, problems caused by contamination of the peripheral circuit during embedding and excessive flow of resin in the subsequent thermal process Provided are a thermosetting resin composition capable of sufficiently suppressing , a semiconductor device manufactured using the same, and a method for manufacturing the same.

2... Adhesive layer, 8... Dicing die bonding integrated tape, 10... Substrate, 11... First wire, 12... Second wire, 10a, 10b... Circuit pattern, 20... First sealing layer (film-like Cured product of adhesive), 20A...adhesive layer, 20P...film adhesive, 40...second sealing layer, 100...semiconductor device, Wa...first semiconductor element, Wb...second semiconductor element

Claims (10)

a substrate;
a first semiconductor element disposed on the substrate;
a first encapsulation layer arranged to cover a region of the substrate where the first semiconductor element is arranged and encapsulating the first semiconductor element;
a second semiconductor element arranged to cover the surface of the first sealing layer opposite to the substrate side and having an area larger than that of the first semiconductor element;
with
The semiconductor device, wherein the first sealing layer is made of a cured thermosetting resin composition, and the thermosetting resin composition has a melt viscosity of 5000 to 11500 Pa·s at 120°C. The thermosetting resin composition contains a low molecular weight component with a molecular weight of 10 to 1,000 and a high molecular weight component with a molecular weight of 100,000 to 1,000,000,
The content M1 of the low molecular weight component is 23 to 35 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition,
2. The semiconductor device according to claim 1, wherein the content M2 of said high molecular weight component is 25 to 45 parts by mass with respect to 100 parts by mass of the resin component contained in said thermosetting resin composition. 3. The semiconductor device according to claim 2, wherein the total amount of said low molecular weight component and said high molecular weight component is 54 to 76 parts by mass with respect to 100 parts by mass of the resin component contained in said thermosetting resin composition. a circuit pattern formed on the surface of the substrate;
a first wire electrically connecting the first semiconductor element and the circuit pattern;
4. The semiconductor device according to claim 1, further comprising: a second wire electrically connecting the second semiconductor element and the circuit pattern;
a second encapsulation layer encapsulating the second semiconductor element and the second wire;
5. The semiconductor device of claim 4, further comprising: 6. The semiconductor device according to claim 1, further comprising a third semiconductor element laminated on said second semiconductor element. A thermosetting resin composition used in the manufacturing process of a semiconductor device,
In the manufacturing process, through a curing treatment of heating the thermosetting resin composition, at least a part of the wire and at least one of the semiconductor elements are embedded in the thermosetting resin composition after the curing treatment. including the process,
A thermosetting resin composition, wherein the thermosetting resin composition has a melt viscosity at 120° C. of 5,000 to 11,500 Pa·s. a low molecular weight component having a molecular weight of 10 to 1000;
a high molecular weight component having a molecular weight of 100,000 to 1,000,000;
including
The content M1 of the low molecular weight component is 23 to 35 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition,
8. The thermosetting resin composition according to claim 7, wherein the content M2 of said high molecular weight component is 25 to 45 parts by mass with respect to 100 parts by mass of the resin component contained in said thermosetting resin composition. The thermosetting according to claim 8, wherein the total amount of the low molecular weight component and the high molecular weight component is 54 to 76 parts by mass with respect to 100 parts by mass of the resin component contained in the thermosetting resin composition. Resin composition. an adhesive layer;
An adhesive layer made of the thermosetting resin composition according to any one of claims 7 to 9,
A dicing die bonding integrated tape.

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