JP2023157426A - Resin composition sheet for electronic component coating, cured product, and semiconductor device - Google Patents

Abstract

To provide a resin composition sheet for electronic component coating which provides a quartz device having a good hollow structure, prevents breakage in mold sealing at high temperature and high pressure, and can maintain the hollow structure.SOLUTION: A resin composition sheet for electronic component coating has a layer 1 and a layer 2, wherein the layer 1 contains a binder polymer, an epoxy resin, a thermosetting resin, a curing catalyst and inorganic particles. In 100 mass% of the whole layer 1, the content of the binder polymer is 40 mass% or more and 90 mass% or less, the layer 2 contains inorganic particles, and the content of the inorganic particles in 100 mass% of the whole layer 2 is larger than the content of the inorganic particles in 100 mass% of the whole layer 1.SELECTED DRAWING: None

Description

The present invention relates to a resin composition sheet for coating electronic parts, a cured product, and a semiconductor device.

In recent years, many electronic components using crystal devices such as crystal resonators and SAW filters have been installed in communication devices such as smartphones and MEMS (MICRO ELECTRO MECHANICAL SYSTEMS). These electronic components have a mechanism that applies the piezoelectric phenomenon of crystal devices to electrical circuits, and are used as synchronization reference signals for various ICs, clocks, pressure sensors and acceleration sensors, and noise filters for communication circuits. Since crystal devices convert electrical signals into physical vibrations or physical vibrations into electrical signals, a hollow space must exist on the active surface of the element, and these elements must be packaged with a hollow structure. There is. Conventionally, in order to protect the element from the external environment, metal sealing was performed by placing the element in an embossed multilayer ceramic, connecting the element and electrodes with wire bonding, and capping the element with metal welding. With the miniaturization and thinning of communication devices such as smartphones, methods for flip-chip connecting the active surface of the element and the package substrate to maintain the space formed by the element, bump, and package substrate, and sheet-like A method has been proposed in which the unevenness formed by electronic component mounting is filled with a resin material to cover and protect the electronic component. (Patent Documents 1, 2)
On the other hand, the demand for miniaturization of crystal devices is progressing further, and the distance between elements is becoming smaller.The distance between elements is now less than 300um, which was previously about 500um to 1mm. Resin sealing has become difficult.

Specifically, while devices are getting smaller, there is a limit to reducing the area of the active surface on the device surface, so the distance between devices is becoming smaller, and the sheet-like material described above is made to conform to the uneven shape. This method has problems in that it does not follow the recesses sufficiently or the sheet-like material may be torn, making it impossible to seal well.

In response, proposals have been made to cover the narrow gap with a highly stretchable sheet material and to embed the chip in a sealing resin layer with controlled meltability. (Patent Documents 3 and 4)

Patent No. 6757787 Patent No. 4730652 Patent No. 06089567 Patent No. 5101931

When applying a highly stretchable sheet material, electronic components protected with a resin sheet only protect the chip with a thin sheet of high stretchability, and have poor resistance to physical impact, water vapor permeability, etc. Because of the lack of reliability, it was necessary to improve reliability by reinforcing it with a metal film such as plating or adding a process to protect the surrounding area with another sealing resin layer.

In the case of the method of embedding chips with a sealing layer with controlled meltability, good sealing is possible when the chips are arranged evenly, but it is difficult to seal when the chips are arranged at multiple intervals. There was an issue with the stopping process. Specifically, when manufacturing a device consisting of a set of two chips, the spacing between the two chips is arranged as small as possible in order to miniaturize the device, and the space between the devices is separated into individual pieces by dicing. are arranged with large intervals between them. (Figure 1) In this case, the resin tends to flow into the narrow gap between the chips, so the resin may seep into the hollow part and cause device malfunction (Figure 2). Therefore, the resin tends to be difficult to embed (FIG. 3), which poses the problem that it is difficult to seal well between chips and between devices under the same conditions. If the resin intrudes into the hollow portion in this way, device characteristics will deteriorate, and if the amount of resin sealed between devices is insufficient, the device sealing resin will peel off during dicing.

Furthermore, in recent years, functional electronic component modules have been proposed in which individually manufactured crystal devices are integrated with other electronic components, and in the manufacturing process of these functional electronic component modules, all electronic components are sealed together. A process (module sealing) is added. For module sealing, an inexpensive compression molding method is used from the viewpoint of manufacturing costs, and molding resin is applied at high temperature and pressure. Encapsulating resins for device encapsulation are specialized for processability, so their storage modulus and glass transition point (Tg) at high temperatures are low, and the device encapsulating resin may be deformed or broken during mold encapsulation. As a result, there was a problem that the mold sealing resin penetrated into the hollow part.

The purpose of the present invention is to suppress resin flow between chips arranged in a narrow gap by combining a layer 1 with extensibility and a layer 2 with a high storage modulus after curing and a high glass transition point after curing. This improves the flow of resin between devices arranged in a wide gap, providing a crystal device with a good hollow structure (Fig. 4), and also maintains the hollow structure without tearing even during mold sealing at high temperature and high pressure. An object of the present invention is to provide a resin composition sheet for covering electronic components that can maintain its structure.

The present invention for solving the above problems is as follows.
(1)
A resin composition sheet having layer 1 and layer 2,
The layer 1 includes a binder polymer, an epoxy resin, a thermosetting resin, a curing catalyst, and inorganic particles,
In the total 100% by mass of the layer 1, the content of the binder polymer is 40% by mass or more and 90% by mass or less,
The layer 2 includes inorganic particles,
A resin composition sheet for covering electronic components, characterized in that the content of inorganic particles in the total 100% by mass of the layer 2 is greater than the content of inorganic particles in the total 100% by mass of the layer 1.
(2)
The layer 2 includes a binder polymer, an epoxy resin, a thermosetting resin, and a curing catalyst,
In the total 100% by mass of the layer 2, the content of the inorganic particles is 40% by mass or more,
The resin composition sheet for covering electronic components according to (1) above, characterized in that the epoxy resin in the layer 2 contains an epoxy resin containing three or four epoxy groups in a single molecule.
(3)
The resin composition sheet for covering electronic components according to (2) above, wherein the thermosetting resin in the layer 2 has an amino group as a functional group.
(4)
The storage modulus at 170° C. of the layer 1 after heat curing at 170° C. for 2 hours is 1 GPa or less,
The layer 2 has a storage modulus of 3 GPa or more at 170° C. after heat curing at 170° C. for 2 hours,
The electronic component coating resin according to any one of (1) to (3) above, wherein the glass transition temperature (Tg) of the layer 2 after heat curing at 170°C for 2 hours is 200°C or higher. Composition sheet.
(5)
The resin composition sheet for covering electronic components according to any one of (1) to (4) above, wherein the layer 2 has a melt viscosity (H1) at 80° C. of 50,000 Pa·s or less.
(6)
The ratio H2/H1 of the melt viscosity (H1) at 80 °C of the layer 2 and the melt viscosity (H2) at 80 °C after heating the layer 2 at 80 °C for 5 minutes is 2 or more. A resin composition sheet for covering electronic components as described in any one of (1) to (5) above.
(7)
The resin composition sheet for covering electronic components according to any one of (1) to (7) above, wherein the layer 1 has a tensile elongation at break at 80° C. of 700% or more.
(8)
A cured product obtained by heating and curing the resin composition sheet for covering electronic components according to any one of (1) to (7) above.
(9)
It has a substrate, a semiconductor chip formed on the substrate, and the cured product according to (8) above, which is laminated so as to cover the semiconductor chip,
A semiconductor device, characterized in that a hollow structure is formed between the substrate and the semiconductor chip.

By sealing a crystal device using the resin composition sheet for covering electronic components of the present invention, even when multiple elements are arranged and the distances between them are different, it is difficult to follow cracks and uneven shapes. It is possible to solve these problems, improve the yield in the processing process, and obtain electronic components with excellent reliability.

FIG. 1 is a schematic diagram of a device protected with a resin composition sheet of the present invention. It is a schematic diagram when resin other than this invention is used and resin permeates into a hollow part. FIG. 3 is a schematic diagram of a case where a resin other than the one according to the present invention is used and a embedding failure occurs between devices. FIG. 2 is a schematic diagram of FIG. 1 successfully sealed using the resin composition sheet of the present invention. FIG. 1 is a cross-sectional view showing a crystal device to which the resin composition sheet for covering electronic components of the present invention is applied. FIG. 2 is a cross-sectional view showing a crystal device to which a resin composition sheet for covering electronic components other than the present invention is applied.

The resin composition sheet for coating electronic components of the present invention is a resin composition sheet having a layer 1 and a layer 2, wherein the layer 1 includes a binder polymer, an epoxy resin, a thermosetting resin, a curing catalyst, and an inorganic particle. The content of the binder polymer is 40% by mass or more and 90% by mass or less based on the total 100% by mass of the layer 1, and the layer 2 contains inorganic particles, and the total amount of the layer 2 is 100% by mass. This is a resin composition sheet for covering electronic components, characterized in that the content of inorganic particles in the layer 1 is greater than the content of inorganic particles in the total 100% by mass of the layer 1.

<Layer 1>
<Binder polymer>
Layer 1 contains a binder polymer. The binder polymer applied to layer 1 functions to give layer 1 extensibility, flexibility, relaxation of thermal stress, and ability to follow unevenness to the chip, and especially if it has these functions, Not limited. Binder polymers in layer 1 include, for example, acrylonitrile-butadiene copolymer (NBR), acrylonitrile-butadiene rubber-styrene resin (ABS), polybutadiene, polyethylene, ethylene-butadiene-ethylene resin (SEBS), acrylic ester and methacrylate. Examples include copolymers (acrylic resins) containing acid esters as an essential copolymerization component, polyvinyl butyral, polyamides, polyesters, polyimides, polyamideimides, and polyurethanes.

Moreover, these binder polymers may have a functional group capable of reacting with a functional group of a thermosetting compound. Specific examples include functional groups such as an amino group, a carboxyl group, an epoxy group, a hydroxyl group, a methylol group, an isocyanate group, a vinyl group, and a silanol group. When the binder polymer has these functional groups, the bond between the thermosetting compound and the binder polymer is strengthened, film strength and reflow heat resistance are improved, and resistance to tearing during uneven processing is also improved.

Among these binder polymers, in order to improve the tensile elongation at break of layer 1, copolymers containing acrylic acid and/or methacrylic acid esters having side chains of 1 to 8 carbon atoms as an essential copolymer component are particularly preferred. It can be used preferably. Further, these copolymers may also have a functional group capable of reacting with the thermosetting resin described below. Specific examples include amino groups, carboxyl groups, epoxy groups, hydroxyl groups, methylol groups, isocyanate groups, vinyl groups, and silanol groups. From the viewpoint of compatibility and reactivity with the epoxy resin, which is a component contained in layer 1, which will be described later, it is particularly preferable to have an epoxy group. Further, it is preferable that the binder polymer contains 30 mol% or more, preferably 35 mol% or more of acrylonitrile units in 100 mol% of the constituent monomer units of the binder polymer. By containing the acrylonitrile unit, the tensile strength at break can be improved without impairing the flexibility of the layer 1, and tearing during unevenness tracking processing can be suppressed.

Further, the weight average molecular weight of the binder polymer in layer 1 is not particularly limited, but the weight average molecular weight is preferably 500,000 to 2,000,000, more preferably 600,000 to 2,000,000. This improves the extensibility of layer 1, improves the ability to track elements with uneven surfaces, and prevents layer 1 from tearing even when the height of the element to be tracked increases. You can follow it till the end.

The content of the binder polymer in layer 1 in the present invention is 40% by mass or more and 90% by mass or less, more preferably 50% by mass or more and 85% by mass or less, even more preferably 55% by mass, based on 100% by mass of the entire layer 1. % or more and 80% by mass or less. By setting the content of the binder polymer to 40% by mass or more with respect to 100% by mass of the entire layer 1, the tensile elongation at break of the layer 1 is improved, and the layer 1 can be made to follow the irregularities of the element without tearing. Furthermore, since the storage modulus of the layer 1 can be lowered, the occurrence of cracks in the layer 1 can be suppressed. Further, by controlling the content of the binder polymer to 90% by mass or less based on 100% by mass of the entire layer 1, the storage modulus of the resin composition sheet can be improved, and the adhesive strength with the substrate can be improved.

<Epoxy resin>
Layer 1 contains epoxy resin. The epoxy resin preferably used for layer 1 in the present invention preferably has two or more epoxy groups in one molecule, and specific examples thereof include cresol novolac type epoxy resin, phenol novolac type epoxy resin, etc. , biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, linear aliphatic epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, spiro Examples include ring-containing epoxy resins. Among these epoxy resins, those that are particularly preferably used in the present invention are biphenyl type epoxy resins and bisphenol A type epoxy resins, which are epoxy resins containing a small amount of chlorine, a low softening point, and a large amount of flexible bifunctional components. These are epoxy resin, bisphenol F type epoxy resin, naphthalene type epoxy resin, and dicyclopentadiene type epoxy resin. Of course, these epoxy resins may be used in combination.

The amount of epoxy resin preferably used in layer 1 in the present invention is preferably 5% by mass or more and 40% by mass or less based on 100% by mass of layer 1 as a whole. By setting the content of epoxy resin to 5% by mass or more, it is possible to increase the adhesive strength between layer 1 and the element, and between layer 1 and the substrate. Peeling of layer 1 can be suppressed during the reliability test conducted below. Further, by controlling the content of the epoxy resin to 40% by mass or less, the flexibility and extensibility of the binder polymer are not impaired, and the ability to follow the irregularities of the element can be improved.

<Thermosetting resin>
Layer 1 contains a thermosetting resin. The thermosetting resin preferably used for layer 1 of the present invention is not particularly limited as long as it causes a thermal reaction with the above-mentioned epoxy resin to form a crosslinked structure. Specific examples of these include phenol novolac resins, cresol novolac resins, various novolac resins synthesized from bisphenol A and resorcinol, acid anhydrides such as maleic anhydride and pyromellitic anhydride, and aromatic amines such as diaminodiphenylsulfone. can be mentioned. Among these thermosetting resins, phenol novolac resins, cresol novolak resins, and diaminodiphenylsulfones are preferably used from the viewpoint of heat resistance and moisture resistance.

The content of the thermosetting resin can be adjusted as appropriate from the viewpoint of reaction with the epoxy resin used, and is not particularly limited, but it can be adjusted depending on the total mole number H of active hydrogen in the thermosetting resin and the epoxy resin. It is preferable that the ratio H/E of the total number of moles of epoxy groups in the resin is in the range of 0.4 to 1.0. When H/E falls within the above range, the crosslinking reaction of the epoxy resin proceeds efficiently, the film strength of the layer 1 is improved, and tearing of the layer 1 during unevenness tracking processing can be suppressed.

<Curing catalyst>
Layer 1 contains a curing catalyst. The curing catalyst preferably used in layer 1 of the present invention is not particularly limited as long as it promotes the curing reaction, and specific examples thereof include 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole, 1-cyanoethyl-2-undecylimidazole, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s -triazine, imidazole compounds such as 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, triethylamine, benzyldimethylamine, α-methylbenzyldimethylamine , tertiary amine compounds such as 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol and 1,8-diazabicyclo(5,4,0)undecene-7, triphenylsulfone, Organic sulfone compounds such as triethylsulfone and tributylsulfone are preferred, and imidazole compounds, triphenylsulfone, 1,8-diazabicyclo(5,4,0)undecene-7 and the like are particularly preferably used.

Note that two or more types of these curing catalysts may be used in combination depending on the application, and the content in layer 1 is 0.1 to 30 parts by mass based on 100 parts by mass of thermosetting resin in layer 1. , more preferably in the range of 1 to 25 parts by mass. By setting the amount of the curing catalyst within this range, it is possible to promote the reaction between the epoxy resin and the thermosetting resin, improve the film strength of layer 1, and suppress tearing during uneven processing. can suppress reactivity and improve storage stability.

<Inorganic particles>
Layer 1 contains inorganic particles. Inorganic particles preferably used for layer 1 in the present invention include fused silica, crystalline silica, calcium carbonate, magnesium carbonate, alumina, silicon nitride, titanium oxide, etc., since their coefficient of linear expansion is low. Fused silica is preferably used. Fused silica here means amorphous silica having a true specific gravity of 2.3 or less. In this method for producing fused silica, it is not necessarily necessary to go through a molten state, and any production method can be used, such as a method of melting crystalline silica or a method of synthesizing it from various raw materials.

The particle size of the fused silica used in the present invention is not particularly limited as long as it does not affect the thickness of layer 1 or the distance between parts to be mounted, but usually those with an average particle size of 20 μm or less are used. It will be done. More preferably, the median diameter D50 of the inorganic particles is preferably 1/5 or less, and even more preferably 1/10 or less, of the thickness of layer 1. When the median diameter is 1/5 or less of the thickness of layer 1, the elongation at break of layer 1 becomes large, and it becomes possible to follow the uneven shape without tearing. The median diameter D50 herein refers to the particle diameter at which the cumulative volume is 50% in a particle distribution curve measured by a laser diffraction particle size distribution measuring device or the like.

Furthermore, in order to improve the wettability between the inorganic particles applied to layer 1 of the present invention and the organic component in the resin composition used for layer 1, the inorganic particles may be surface-treated with a silane coupling agent. good. Specific examples of silane coupling agents include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and vinyltrimethoxysilane. Silane, vinyltriethoxysilane, 2-(3,4epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3 -Methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2 (amino ethyl)3-aminopropylmethyldimethoxysilane, N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1 , 3-dimethyl-butylidene)propylamine, 3-ureidopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, etc., but are not particularly limited. It's not a thing. The silane coupling agent may be used alone or in combination with the above silane coupling agents, and the amount used in the treatment is 0.3 to 1 part by mass per 100 parts by mass of inorganic particles. is preferred.

Further, the content of the inorganic particles used in the layer 1 of the present invention is preferably 5% by mass to 40% by mass based on 100% by mass of the entire layer 1. By containing 5% by mass or more of inorganic particles in 100% by mass of the entire layer 1, the film strength of the layer 1 can be improved and breakage during processing to follow the irregularities of the element can be suppressed. Further, by containing 40% by mass or less of inorganic particles in 100% by mass of the entire layer 1, it is possible to improve the followability to irregularities without impairing the flexibility and extensibility of the binder polymer.

<Others>
In addition to the above-mentioned components, organic and inorganic components such as antioxidants and ion scavengers can be added to the resin composition used in Layer 1 of the present invention, to the extent that they do not impair the properties of the resin composition. . Examples of organic components include styrene, NBR rubber, acrylic rubber, and crosslinked polymers such as polyamide. Examples of antioxidants include hindered phenol-based and amine-based primary antioxidants, and sulfur-based and phosphorus-based secondary antioxidants. Examples of the ion scavenger include antimony trioxide, antimony pentoxide, and hydrotalcite compounds. These may be used alone or in combination of two or more.

In the resin composition sheet of the present invention, the thickness of layer 1 is not particularly limited, but it is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm, and even more preferably 15 μm to 30 μm. In order to further reduce the size and height of the device, it is preferable that layer 1 be as thin as possible without causing tearing.

Layer 1 in the resin composition sheet of the present invention preferably has a 170°C storage modulus of 1 GPa or less, and preferably 1 MPa or more after being heat-cured at 170°C for 2 hours. If layer 1 has a storage modulus of 1 GPa or less at 170°C after heating and curing at 170°C for 2 hours, when heat is applied to the device and expansion or contraction occurs in the element or substrate, layer 1 and Since it is possible to follow the deformation of the electronic component in contact with it and to relieve stress, cracking and peeling of the layer 1 can be suppressed. In particular, cracking and peeling can be suppressed when performing a thermal load test such as a thermal cycle. In order to make the storage modulus of layer 1 1 GPa or less after heat curing at 170° C. for 2 hours, the content of the binder polymer in 100% by mass of the entire layer 1 should be 40% by mass or more, and the content of inorganic particles should be This can be achieved by reducing the amount of epoxy resin to 40% by mass or less, using a difunctional epoxy resin, etc.

The tensile elongation at break at 80°C of the layer 1 of the present invention is preferably 700% or more, more preferably 700% or more and 3000% or less, still more preferably 800% or more and 2500% or less, particularly preferably It is 1000% or more and 2000% or less. Layer 1 has the role of following the unevenness of the crystal device after being formed into a laminate with layer 2 as described later. However, if the tensile elongation at 80°C of layer 1 is 700% or more, It can follow uneven shapes without tearing. Further, if the tensile elongation at break at 80° C. of the layer 1 is 3000% or less, it is possible to prevent the layer 1 from extending and entering the hollow portion of the device.

In order to make the tensile elongation at break at 80°C of layer 1 700% or more, the content of the binder polymer should be 40% by mass or more based on 100% by mass of the entire layer 1, and the type of binder polymer should be adjusted by changing the number of carbon atoms. This can be achieved by using a copolymer containing acrylic acid and/or methacrylic acid ester having 1 to 8 side chains as an essential copolymer component.

In addition, in order to make the tensile elongation at break at 80°C of layer 1 3000% or less, the amount of binder polymer added should be 90% by mass or less based on the entire layer 1, and the amount of inorganic particles added should be reduced to the entire layer 1. This can be achieved by reducing the amount to 40% or less.

<Layer 2>
The resin composition sheet for covering electronic components of the present invention has layer 1 and layer 2. That is, the resin composition sheet for covering electronic components of the present invention has a structure in which layer 1 is further laminated with a layer containing inorganic particles (hereinafter referred to as layer 2). By laminating Layer 2 on Layer 1, Layer 2 softens in the process of making the resin composition sheet for covering electronic components follow the uneven shape formed by placing multiple elements on the substrate. By pressing layer 1, it is easier to follow the uneven shape, and by thermosetting layer 2, the organic resin composition sheet for covering electronic components adheres to, covers, and protects the uneven shape, and further It is possible to provide an electronic component with excellent reliability, the outside of which is protected by layer 2 made of a thermosetting resin composition.

When the organic resin composition sheet for covering electronic components of the present invention having layer 1 and layer 2 is used for coating electronic components, it is coated in such a manner that the electronic component and the layer 1 side face each other. It is preferable to do so.

Layer 2 in the resin composition sheet for covering electronic components of the present invention contains inorganic particles. The content of inorganic particles in 100% by mass of layer 2 is greater than the content of inorganic particles in 100% by mass of layer 1. Layer 2, which contains a large amount of inorganic particles, has a high storage modulus and film strength, and by placing it on the opposite side of the crystal device to layer 1, layer 1 follows the uneven shape of the crystal device and is sealed. The reliability of the crystal device is improved because the protected structure can be reinforced.

Layer 2 of the invention may contain a binder polymer, an epoxy resin, a thermosetting resin, and a curing catalyst.

<Inorganic particles>
The inorganic particles used in layer 2 of the present invention can have the same composition as the inorganic particles in layer 1 described above.

The average particle size of the inorganic particles used in layer 2 of the present invention is not particularly limited, as long as it does not affect the thickness of the resin composition sheet or the followability of the resin composition sheet between the parts to be mounted. is 0.2 to 20 μm, more preferably 0.2 to 10 μm. By setting the average particle size of the inorganic particles to 20 μm or less, the inorganic particles will not inhibit the flowability of the resin when the layer 2 is embedded in the unevenness of the device. Further, by setting the thickness to 0.2 μm or more, the dispersibility of the inorganic particles in the resin composition is improved, and the fluidity of the layer 2 is also improved, so that the spaces between the chips can be satisfactorily filled with the resin of the layer 2.

Moreover, there is no restriction at all in mixing the inorganic particles used in layer 2 of the present invention having two or more types of average particle diameters. By using inorganic particles having two or more types of average particle diameters in combination, the fluidity of the layer 2 can be improved, and the flow of the resin between the unevenness of the element can be improved. Among them, it is preferable to use inorganic particles with an average particle size of 3 μm or more and inorganic particles with an average particle size of 2 μm or less in combination. It is more preferable to mix them in a weight ratio of 30/70. By using inorganic particles having the above-mentioned average particle size in the above-mentioned formulation, the resin flow properties of the layer 2 can be improved.

Further, the inorganic particles used in the layer 2 of the present invention preferably account for 40% by mass or more, more preferably 40% to 90% by mass, even more preferably 50% by mass, based on 100% by mass of the entire layer 2. % by weight to 90% by weight, particularly preferably 60% to 85% by weight. By setting the content of inorganic particles in 100% by mass of the entire layer 2 to 40% by mass or more, the storage modulus of layer 2 after thermosetting can be improved, and by setting the content of inorganic particles to 85% by mass or less By doing so, the inorganic particles can be well dispersed in the resin composition, so that the sheet-like shape can be maintained without impairing the flexibility of the resin composition sheet for covering electronic components, and the particle size is 100 μm or less. It can be made into a thin sheet.

Furthermore, the inorganic particles used in layer 2 of the present invention are not subject to any restrictions in surface treatment with a silane coupling agent or the like in order to improve dispersibility in the resin composition. Preferably used silane coupling agents are not particularly limited as long as they react with functional groups such as hydroxyl groups present on the surface of inorganic particles and enhance affinity with other additive resins, and specific examples thereof include: , vinyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)trimethoxysilane, 3-glycidoxypropyltrimethoxysilane, phenyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane , N-2(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and their triethoxy Examples include silane. In layer 2 of the present invention, the amount of the silane coupling agent blended is such that the ratio of the minimum covered area (m ² /g) of the silane coupling agent used to the specific surface area of the inorganic filler is usually 0.4 to 3.0, more preferably 0.8 to 2.0.

<Binder polymer>
Layer 2 of the invention preferably comprises a binder polymer. The binder polymer preferably used in layer 2 of the present invention is not subject to any restrictions as long as it can impart sheet shape and flexibility to layer 2, and is used in layer 1 described above. The same binder polymer can be suitably used.

The content of the binder polymer in the layer 2 of the present invention is preferably 2% by mass to 25% by mass based on the entire layer 2. By setting the binder polymer to 2% by mass or more, the shape of the resin composition when formed into a sheet becomes stable. Furthermore, since the water vapor permeability can be lowered, the reliability of the device after the laminate of layer 1 and layer 2 is sealed into the device can be improved. Further, by controlling the binder polymer to 25% by mass or less, the fluidity of the layer 2 can be improved, and the layer 1 can sufficiently play the role of pushing the layer 1 into the unevenness of the element.

<Epoxy resin>
Layer 2 of the present invention preferably contains an epoxy resin. The epoxy resin in the layer 2 is not particularly limited as long as it is an epoxy resin, but it is preferable that the epoxy resin includes an epoxy resin having three or four epoxy groups in a single molecule. There are no particular limitations as long as there are 3 or 4 epoxy groups in a single molecule, but examples include tetrakisphenolethane type, trishydroxyphenylmethane type, diphenyldiaminomethane type, aminophenol type, and phenol novolak type. Examples include epoxy resins such as. Among these, it is more preferable to use tetrakisphenolethane type, diphenyldiaminomethane type, and aminophenol type epoxy resins, especially from the viewpoint of reactivity with thermosetting resins. By using an epoxy resin that has 3 or 4 epoxy groups in a single molecule, the crosslinking density increases, increasing the storage modulus and glass transition point of the resin composition sheet for coating electronic components after curing. This makes it possible to improve pressure resistance when sealing the module.

Furthermore, as mentioned above, the layer 2 of the present invention preferably contains an epoxy resin having three or four epoxy groups in a single molecule, but other epoxy resins, that is, one or two epoxy groups in a single molecule. , or an epoxy resin having five or more epoxy groups is not particularly limited.

Furthermore, the epoxy resin used for layer 2 of the present invention is preferably a mixture of an epoxy resin that is solid at room temperature and an epoxy resin that is liquid at room temperature. By mixing epoxy resins with different shapes at room temperature, it is possible to arbitrarily control the tackiness of the surface of the resin composition sheet for coating electronic components at room temperature, and also to improve the meltability during sealing processing into device elements. It becomes possible to control and perform good sealing processing.

<Thermosetting resin>
Layer 2 of the present invention preferably contains a thermosetting resin. The thermosetting resin preferably used in layer 2 is selected from those that cure by reacting with epoxy resins, and from the viewpoint of heat resistance, moisture resistance, and reactivity with epoxy groups, thermosetting resins that have amino groups as functional groups are selected. Curable resins are preferred, and specific examples of thermosetting resins having an amino group as a functional group include diamino aromatic amines such as diaminodiphenylsulfone. Since Layer 2 contains a thermosetting resin containing an amino group as a functional group, crosslinking with the epoxy group proceeds efficiently, improving the storage modulus after curing and the glass transition point after curing of Layer 2. be able to.

The content of the thermosetting resin preferably used in layer 2 of the present invention can be adjusted appropriately from the viewpoint of reaction with the epoxy resin used, and is not particularly limited. The ratio H/E of the total number of moles of active hydrogen H to the total number of moles of epoxy groups E in the epoxy resin is preferably in the range of 0.5 to 1.5. When H/E falls within the above range, the crosslinking reaction of the epoxy resin proceeds efficiently, and the storage modulus and glass transition point after curing can be increased. Furthermore, since the crosslinking reaction proceeds rapidly during heat curing, the layer 2 can be cured without deforming its shape.

<Curing catalyst>
Layer 2 of the invention preferably contains a curing catalyst. The curing catalyst preferably used in layer 2 is not particularly limited, and one having the same composition as the inorganic particles in layer 1 described above can be used.

The content of the curing catalyst is preferably in the range of 0.1 to 30 parts by weight, more preferably 5 to 25 parts by weight, based on 100 parts by weight of the thermosetting resin. As a result, the storage stability can be improved, the resin can be cured without deformation during heat curing, and the storage modulus and glass transition point after curing can be improved, and mold sealing resistance can be imparted.

<Others>
Layer 2 of the present invention may further contain various additives. For example, flame retardants such as halogen compounds and phosphorus compounds, carbon black, olefin copolymers, various elastomers such as modified nitrile rubber, modified butadiene rubber, and modified polybutadiene rubber, fillers such as titanate coupling agents, surface treatment agents such as hydrocarbons, etc. Examples include ion scavengers such as talcites.

Layer 2 of the present invention preferably has a storage modulus at 170°C of 3 GPa or higher and a glass transition point of 200°C or higher after heating and curing at 170°C for 2 hours, more preferably heating at 170°C for 2 hours. The 170°C storage modulus after curing is 4GPa or more and 12GPa or less, the glass transition point is 210°C or more and 270°C or less, and more preferably the 170°C storage modulus after heat curing at 170°C for 2 hours is 5GPa or more. The glass transition point is 220°C or higher and 260°C or lower. If Layer 2 has a storage modulus of 3 GPa or more at 170°C and a glass transition point of 200°C or more after being heat-cured at 170°C for 2 hours, high temperature and high pressure force will not be applied during module sealing. It is possible to suppress the deformation of the layer 2 even when the module is sealed, and also to prevent the module sealing resin from flowing into the hollow portion. Furthermore, since the glass transition point is 200° C. or higher, thermal cycling properties and reflow resistance are improved, and the reliability of a crystal device using layer 2 of the present invention is improved.

In order to make the storage modulus at 170 degrees of layer 2 after heating and curing at 170°C for 2 hours to be 3 GPa or more and the glass transition point to be 200°C or more, the content of inorganic particles in 100% by mass of the entire layer 2 must be is 40% by mass or more, the epoxy resin in layer 2 is an epoxy resin having three or four epoxy groups in a single molecule, and the thermosetting resin in layer 2 is a thermosetting resin having an amino group. This is achieved by applying a synthetic resin.

The melt viscosity (H1) at 80°C of layer 2 of the present invention is preferably 50,000 Pa·s or less, more preferably 50 Pa·s or more and 10,000 Pa·s or less, and 100 Pa·s or more and 5,000 Pa·s or less. It is more preferable that By lowering the melt viscosity, the laminate of layer 2 and layer 1 can fit into the gap between the elements of the device, allowing the elements to be sealed well.

In order to reduce the melt viscosity (H1) at 80°C of layer 2 to 50,000 Pa・s or less, it is necessary to perform surface treatment on the inorganic particles, apply inorganic particles with different particle sizes, and increase the amount of binder polymer added. can be achieved with.

The ratio H2/H1 of the melt viscosity at 80°C (H1) of layer 2 of the present invention and the melt viscosity at 80°C (H2) after heating layer 2 at 80°C for 5 minutes is preferably 2 or more. , more preferably 2 or more and 5 or less. By setting the ratio H2/H1 to 2 or more, when heated at 80°C for 5 minutes, the crosslinking reaction progresses and the melt viscosity increases, so that the resin composition sheet for covering electronic parts can be applied to crystal devices. It is possible to suppress deformation of the resin composition sheet when the pressure during processing is released. Further, when crosslinking proceeds under heating conditions of 80° C. for 5 minutes, the processing temperature and processing time can be adjusted to achieve the optimum degree of progress of the curing reaction. When H2/H1 is smaller than 2, a force acts to cause layer 1, which has been stretched so as to follow the irregularities of the crystal device, to return to its original shape, and the shape of layer 2 is deformed.

In order to make H2/H1 2 or more, the ratio H/E of the total number of moles of active hydrogen in the thermosetting resin H to the total number of moles of epoxy groups in the epoxy resin E should be 0.5 to 1.5. This can be achieved by making appropriate changes within this range and by adjusting the type and amount of the curing catalyst.

The resin composition sheet for covering electronic components of the present invention is a laminate having layer 1 and layer 2. The resin composition sheet of the present invention may further include a protective film. Such a protective film may be provided on only one side of the resin composition sheet for covering electronic components, or may be provided on both sides. Specific examples of the protective film include polyethylene terephthalate film, polyethylene film, polyolefin film, polyimide film, polyamide film, metal foil such as copper and aluminum, and the like. In addition, if the protective film is to be peeled off during the processing process, a release layer of silicone, fluorine compound, alkyd compound, etc. should be applied to ensure a peeling force that does not leave any marks on the surface of the resin composition sheet for covering electronic components. It may be a film base material provided with. Moreover, if the protective films on both sides are to be peeled off, there is no restriction at all in applying a difference in peeling force so that a predetermined film base material can be peeled off.

The cured product of the present invention is a cured product obtained by heating and curing the resin composition sheet for coating electronic components of the present invention.

Further, the semiconductor device of the present invention includes a substrate, a semiconductor chip formed on the substrate, and a cured product of the present invention laminated to cover the semiconductor chip. It is characterized by having a hollow structure formed therein. It can be manufactured by laminating the resin composition sheet for covering electronic parts of the present invention so as to cover the semiconductor chip, and then curing the resin composition sheet for covering electronic parts by heating. A feature is that a hollow structure is formed between semiconductor chips.

By manufacturing the semiconductor device using the resin composition sheet for covering electronic components, it is possible to seal the semiconductor device without infiltration of the sealing resin, and furthermore, the processed semiconductor device has high durability. It has moldability, reflow resistance, and thermal cycle resistance.

The present invention will be specifically explained below based on Examples, but the present invention is not limited thereto. In addition, details of the raw materials indicated by abbreviations in each example are shown below.

<Binder polymer>
Binder polymer 1: Acrylic copolymer In a reactor equipped with a mixer and a cooler, 106 g (2.00 mol) of acrylonitrile (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) and butyl acrylate (Wako Pure Chemical Industries, Ltd.) were added to a reactor equipped with a mixer and a cooler under a nitrogen atmosphere. 231 g (1.80 mol) of glycidyl methacrylate (special grade, manufactured by Wako Pure Chemical Industries, Ltd.), 28 g (0.20 mol) of glycidyl methacrylate (manufactured by Wako Pure Chemical Industries, Ltd., special grade), and 2900 g of methyl ethyl ketone (manufactured by Wako Pure Chemical Industries, Ltd., first grade) as a solvent. (1013 hPa) and 0.001 g of 2-ethylhexylmercaptoacetate (manufactured by Wako Pure Chemical Industries, Ltd.) as a chain transfer agent, and azobisisobutyronitrile (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator. V-60) was added and polymerized until the weight average molecular weight reached 700,000. The weight average molecular weight was measured by GPC (gel permeation chromatography) method (apparatus: GELPERMATION Chromatography graph manufactured by Tosoh Corporation, column: TSK-GEL GMHXL 7.8×300 mm manufactured by Tosoh Corporation), and calculated in terms of polystyrene.
As a result, an acrylic copolymer 1 having a molar ratio of acrylonitrile:butyl acrylate:glycidyl methacrylate=50:45:5 (weight average molecular weight 700,000) was obtained.

Binder polymer 2: Carboxyl group-containing acrylonitrile butadiene rubber (weight average molecular weight 400,000, PNR-1H, manufactured by JSR Corporation)
Binder polymer 3: Phenoxy resin (weight average molecular weight: 50,000, Phenotote YP-50 manufactured by Toto Kasei Co., Ltd.)
<Epoxy resin>
Epoxy resin 1: Bisphenol A type epoxy resin (jER-1001, epoxy equivalent: 475, manufactured by Mitsubishi Chemical Corporation, number of epoxy groups in a single molecule: 2, solid at room temperature)
Epoxy resin 2: Bisphenol A type epoxy resin (jER-828, epoxy equivalent: 190, manufactured by Mitsubishi Chemical Corporation, number of epoxy groups in a single molecule: 2, liquid at room temperature)
Epoxy resin 3: diphenyldiaminomethane type epoxy resin (jER604, epoxy equivalent: 120, manufactured by Mitsubishi Chemical Corporation, number of epoxy groups in a single molecule: 4, liquid at room temperature)
Epoxy resin 4: Tetrakisphenolethane type epoxy resin (jER1031S, epoxy equivalent: 200, manufactured by Mitsubishi Chemical Corporation, number of epoxy groups in a single molecule: 4, solid at room temperature)
Epoxy resin 5: Aminophenol type epoxy resin (jER630, epoxy equivalent: 96, manufactured by Mitsubishi Chemical Corporation, number of epoxy groups in a single molecule: 3, liquid at room temperature)
<Thermosetting resin>
Thermosetting resin 1: 4,4'-diaminodiphenylsulfone (Seikacure S, amine equivalent: 62, manufactured by Wakayama Seika Kogyo Co., Ltd.)
Thermosetting resin 2: Novolak phenol (H-1, hydroxyl equivalent: 106, manufactured by Meiwa Kasei Co., Ltd.)

<Curing catalyst>
Curing catalyst 1: 2-heptadecylimidazole (c17z, manufactured by Shikoku Kasei Co., Ltd.)
Curing catalyst 2: 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine (c11Z-A, manufactured by Shikoku Kasei Co., Ltd.)
Curing catalyst 3: Triphenylphosphine (TPP, manufactured by Tokyo Chemical Industry Co., Ltd.)
<Inorganic particles>
Inorganic particles 1: SO-C1 (average particle size 0.25 μm, manufactured by Admatex Co., Ltd.)
Inorganic particles 2: FB-3D (average particle size 3 μm, manufactured by Denki Kagaku Kogyo Co., Ltd.)
Inorganic particles 3: SO-C2 (average particle size 0.5 μm, manufactured by Admatex Co., Ltd.)
Inorganic particles 4: FB-20D (average particle size 22 μm, manufactured by Denki Kagaku Kogyo Co., Ltd.)

<Silane coupling agent>
Silane coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane (KBM-573, manufactured by Shin-Etsu Silicone Co., Ltd.)
Silane coupling agent 2; phenyltrimethoxysilane (KBM-103, Shin-Etsu Silicone)
<Other additives>
Ion scavenger: Hydrotalcite compound (DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.)
Carbon black: MA100 (average particle size 24 nm, manufactured by Mitsubishi Chemical Corporation)
<Creation of paint solution for layer 1>
The method for preparing the resin composition of Example 1-1 is shown below as an example.

Binder polymer 1 (acrylic copolymer) 45 g, epoxy resin 1 (bisphenol A type epoxy resin, jER-1001, epoxy equivalent: 475, manufactured by Mitsubishi Chemical Corporation) 32 g, thermosetting resin 1 (4,4'- Diaminodiphenylsulfone, Seikacure S, amine equivalent: 62, manufactured by Wakayama Seika Kogyo Co., Ltd.) 2.1 g, inorganic particles 1 (SO-C1, average particle size 0.25 μm, manufactured by Admatex Co., Ltd.) 20 g, curing catalyst 1 (2-heptadecyl imidazole, c17z, manufactured by Shikoku Kasei Co., Ltd.) 0.1 g, ion scavenger (hydrotalcite compound, DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.) 1 g, solid content concentration 20 mass %, and stirred and dissolved at 40° C. to prepare a coating solution for layer 1.

Examples 1-2 to 1-6 and Comparative Examples 1-1 to 1-3 were the same as Example 1-1 except that the types and amounts of each composition were changed as described in Table 1. A coating solution for layer 1 was prepared.

<Creation of paint solution for layer 2>
The method for preparing the resin composition of Example 2-1 is shown below as an example.
Put 59.70 g of inorganic particles 3 (SO-C2, average particle size 0.5 μm, manufactured by Admatex Co., Ltd.) into a mixer, and add silane coupling agent 1 (N-phenyl-3-aminopropyltrimethoxysilane, 0.6 g of KBM-573 (manufactured by Shin-Etsu Silicone Co., Ltd.) was sprayed with a sprayer and stirred in a mixer to perform surface treatment of the inorganic particles. Methyl isobutyl ketone was added to the surface-treated inorganic particles so that the solid content concentration was 60% by mass, and after stirring at 30° C., the particles were treated with a homomixer to prepare a slurry. To the prepared slurry were added 5 g of binder polymer 2 (carboxyl group-containing acrylonitrile butadiene rubber, weight average molecular weight 400000, PNR-1H, manufactured by JSR Corporation), 313.4 g of epoxy resin, 413.4 g of epoxy resin, and 8.1 g of thermosetting resin. , 10.1 g of curing catalyst and 0.3 g of carbon black were added, and methyl isobutyl ketone was added so that the solid content concentration of the mixture was 65% by mass, and the mixture was stirred and dissolved at 40°C to prepare a coating solution for layer 2. did.

The types and amounts of each composition in Examples 2-2 to 2-12 and Comparative Examples 2-1 to 2-2 were changed as shown in Table 2-1 and Table 2-2. A coating solution for layer 2 was prepared in the same manner as in step 1.

<Sheet processing of coating solution for layer 1 and layer 2>
Apply the paint solution for layers 1 and 2 to a 38 μm thick polyethylene terephthalate film (PET38 manufactured by Lintec Corporation) with a silicone release agent using a bar coater so that the thickness after drying is 20 μm for layer 1 and 10 to 50 μm for layer 2. After drying at 110°C for 5 minutes, a protective film (“Film Bina” GT manufactured by Fujimori Industries Co., Ltd.) was attached, and a 38 μm thick polyethylene terephthalate film with a silicone mold release agent (manufactured by Lintec Corporation) was attached. A laminate was prepared in which PET38), a resin composition sheet for covering electronic parts, and a protective film ("Film Biner" GT manufactured by Fujimori Industries, Ltd.) were laminated in this order.

Subsequently, Layer 2 was laminated using a roll laminator so that the resin composition had the thickness shown in Table 2. Lamination conditions were 80° C. and 0.5 m/min.

<Layer 2 sheet film evaluation>
By the above method, the compositions of the Examples and Comparative Examples shown in Table 2 were formed into sheets with a thickness of 50 μm, and the appearance was evaluated. When the film surface was visually observed, if pinholes, coating unevenness, or unevenness was observed, it was marked as ×; when resin unevenness was observed on microscopic observation, it was marked as △, otherwise it was marked as ○.

<Method for measuring melt viscosity of layer>
The created layer 2 was laminated under the conditions of a laminating roll temperature of 70° C., a laminating pressure of 0.3 MPa, and a laminating speed of 1 m/min to produce a sample with a thickness of about 500 μm. The laminated sample was cut out into a circle with a diameter of 15 mm, and the temperature was raised to 80 °C using a viscoelasticity measuring device (AR-G2) manufactured by TA Instruments at a shear rate of 50 s-1, a strain of 1%, and a heating rate of 5 °C/min. After raising the temperature, measure the melt viscosity under the heating conditions of holding the temperature at 80°C for 5 minutes, read the melt viscosity |η*| at the time it reaches 80°C, set it as H1, and hold the temperature at 80°C for 5 minutes. The melt viscosity |η*| after the elapse of time was read and designated as H2.

<Tensile elongation measurement method>
The resin composition sheet for coating electronic components was subjected to a tensile test at a speed of 50 mm/min with a tensile tester (UCT100 model, manufactured by Orientec Co., Ltd.) under conditions of a sample length of 40 mm between chucks and a width of 5 mm, which resulted in breakage. The stress-strain curve was recorded, and the tensile elongation at break (5) at 80°C was determined.

<Storage modulus, glass transition temperature measurement method>
A test piece with a thickness of 200 μm was prepared by laminating a plurality of resin composition sheets, and evaluation was performed using this test piece. In addition, when the resin composition sheet has a laminated structure, a plurality of layers each of Layer 1 and Layer 2 are laminated using the laminating conditions of laminating roll temperature of 70 ° C., lamination pressure of 0.3 MPa, and lamination speed of 1 m/min. A test piece was prepared, and this test piece was heated in an oven at 170°C for 2 hours to obtain a cured product. For evaluation, the storage modulus and glass transition point at 170° C. were determined using a dynamic viscoelasticity device DMS6100 manufactured by SII under conditions of a frequency of 1 Hz and a heating rate of 5° C./min. The glass transition point was defined as the temperature at which tan δ=loss elastic modulus/storage elastic modulus takes a maximum value as measured by a dynamic viscoelasticity device.

<Coverability evaluation>
The covering properties of the surface of a substrate on which a plurality of electronic components were mounted with an organic resin composition sheet for covering electronic components were evaluated according to the following procedure.

As a board on which multiple electronic components are mounted, a Si chip for evaluation with a width of 0.9 mm x length of 1.1 mm x height of 0.3 mm is flip-chip mounted on an alumina board via solder bumps of 0.04 mm in height. A mounted board was used. The Si chips are mounted in 5 rows x 6 columns in the center of a 10 cm x 10 cm alumina substrate, and the intervals between the mounted Si chips are 1st and 2nd columns, 3rd and 4th columns, and 5th column. The interval between the and the 6th row was 0.05 mm, and the interval between the 2nd and 3rd row, and the 4th and 5th row was 0.25 mm. A resin composition sheet with a protective film attached to one side was placed on the substrate on which the plurality of electronic components described above were mounted, with the side without the protective film facing the substrate. (Step 1) When the resin composition sheet used had a laminated structure of layer 1 and layer 2, the protective film on the layer 1 side was peeled off, and the sheet was placed so that the layer 1 side faced the substrate. Further, the layers were laminated under the conditions of a laminating roll temperature of 70° C., a laminating pressure of 0.3 MPa, and a laminating speed of 1 m/min so that the thickness of layer 2 was 200 μm.

Next, the remaining protective film was peeled off, and the above substrate was placed on a smooth aluminum plate with the side on which the resin composition sheet was placed facing up. A thick PET film was placed so that the release layer and the resin composition sheet were in contact with each other, and MVLP manufactured by Meiki Seisakusho Co., Ltd. was applied under the conditions of 30 seconds of evacuation time, 80° C. temperature, and 0.5 MPa of vacuum pressure. Vacuum lamination was carried out using (Step 2)
Next, the substrate coated with the resin composition sheet was heat-cured at 170° C. for 2 hours in an air oven. (Step 3)
The appearance after coating with the resin composition sheet was evaluated based on the following criteria.

(a) Evaluation of coverage of resin composition sheet at 0.05 mm spacing between Si chips. Check whether the resin composition sheet follows the irregularities formed by mounting Si chips on an alumina substrate using a microscope at 20 locations between the corresponding rows. It was observed and judged by observation. Those in which the resin composition sheet was not torn and the upper part of layer 2 had a flat shape were judged to be acceptable. If Layer 1 of the resin composition sheet is torn or if Layer 2 flows closer to the Si chip than Layer 1, it is judged as a failure, and the number of places judged to be acceptable out of the 20 observed points is calculated. It is shown in Table 3.

(b) Evaluation of coverage of resin composition sheet at 0.25 mm interval between Si chips The appearance of the resin composition sheet was evaluated by microscopic observation of the cross section of the structure covered with the resin composition sheet. Specifically, the shortest distance between the bump that connects the substrate and the Si chip and the coated resin composition sheet was measured, and ◎ if it was 0 to 20 μm, ○ if it was 20 to 40 μm, and ○ if it was 40 μm or more. The case was marked as ×.

<Resin deformation between chips after curing>
The Si chips were sealed in the same manner as in the evaluation of coverage, and after heating and curing at 170° C. for 2 hours, the cross section of the test piece was observed, and the portion between the chips was observed using a microscope. The results were compared with the shape before curing to determine whether the resin had been deformed.

<Mold sealing material>
As a mold sealant, 11.67% by weight of biphenyl epoxy resin, 6.5% by weight of phenol novolak resin, 0.53% by weight of curing accelerator, and 80% by weight of fused silica were treated with 0.7% by weight of silane coupling agent. A mixture of 0.3% by weight of carbon black and 0.3% by weight of carnauba wax was used.

<Mold sealing test>
In the coverage evaluation, the mold sealing resistance test was conducted for the level where the pass judgment was 15/20 or more in (a) and the judgment of ◎ or ○ in (b). Specifically, the mold sealing material was set in a compression mold sealing tester, and sealing was performed at 170° C. and 3 MPa, 5 MPa, or 8 MPa, and then the cross section of the chip was observed. Table 3 shows the number of mold resins flowing into the hollow structure between the substrate and the Si chip. Five test pieces were observed under each mold pressure condition, and when the number of mold resin inflow chips was 0 to 1/5, it was determined that the mold pressure condition was passed. Further, the results of each mold pressure condition were evaluated as follows.
◎: Passed under all conditions of 3, 5, and 8 MPa 〇: Passed at 3 and 5 MPa △: Passed only at 3 MPa ×: Fail under all conditions <Reflow resistance test>
In the coverage evaluation, a reflow resistance test was conducted for the levels where the pass judgment was 15/20 or more in (a) and the judgment of ◎ or ○ in (b). Specifically, each test piece was allowed to absorb moisture for 168 hours at 30° C. and 70% RH, and then immediately subjected to IR reflow at a temperature of 260° C. for 10 seconds, and the state of peeling and cracking was observed. In microscopic observation of the cross section of the test piece, if peeling or cracking was observed in the resin composition sheet or the bump portion of the Si chip, it was judged as ×, and if no cracks were observed, it was judged as ○.

In Tables 1 and 2, the unit of content is mass %.

1: Substrate 2: Chip 3: Bump 4: Chip gap 5: Device gap 6: Device sealing resin 7: Layer 1
8: Layer 2
9: Module sealing

Claims (9)

A resin composition sheet having layer 1 and layer 2,
The layer 1 includes a binder polymer, an epoxy resin, a thermosetting resin, a curing catalyst, and inorganic particles,
In the total 100% by mass of the layer 1, the content of the binder polymer is 40% by mass or more and 90% by mass or less,
The layer 2 includes inorganic particles,
A resin composition sheet for covering electronic components, characterized in that the content of inorganic particles in the total 100% by mass of the layer 2 is greater than the content of inorganic particles in the total 100% by mass of the layer 1. The layer 2 includes a binder polymer, an epoxy resin, a thermosetting resin, and a curing catalyst,
In the total 100% by mass of the layer 2, the content of the inorganic particles is 40% by mass or more,
2. The resin composition sheet for covering electronic components according to claim 1, wherein the epoxy resin in the layer 2 includes an epoxy resin containing three or four epoxy groups in a single molecule. 3. The resin composition sheet for covering electronic components according to claim 2, wherein the thermosetting resin in the layer 2 has an amino group as a functional group. The storage modulus at 170° C. of the layer 1 after heat curing at 170° C. for 2 hours is 1 GPa or less,
The layer 2 has a storage modulus of 3 GPa or more at 170° C. after heat curing at 170° C. for 2 hours,
The resin composition sheet for covering electronic components according to claim 1, wherein the glass transition temperature (Tg) of the layer 2 after heat curing at 170°C for 2 hours is 200°C or higher. The resin composition sheet for covering electronic components according to claim 1, wherein the layer 2 has a melt viscosity (H1) of 50,000 Pa·s or less at 80°C. The ratio H2/H1 of the melt viscosity (H1) at 80 °C of the layer 2 and the melt viscosity (H2) at 80 °C after heating the layer 2 at 80 °C for 5 minutes is 2 or more. The resin composition sheet for covering electronic components according to claim 1. The resin composition sheet for covering electronic components according to claim 1, wherein the tensile elongation at 80°C of the layer 1 is 700% or more. A cured product obtained by heating and curing the resin composition sheet for covering electronic components according to any one of claims 1 to 7. It has a substrate, a semiconductor chip formed on the substrate, and the cured product according to claim 8, which is laminated so as to cover the semiconductor chip,
A semiconductor device, characterized in that a hollow structure is formed between the substrate and the semiconductor chip.

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