JP2014232854A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve connection reliability of a semiconductor device under a high-temperature environment.SOLUTION: A semiconductor device 100 of the present invention includes: a semiconductor element 101; a resin substrate 102 on at least one surface of which the semiconductor element 101 is mounted; an electrode pad 103 provided on the semiconductor element 101; a copper wire 107 for connecting a connection terminal 105 provided on the resin substrate 102 to the electrode pad 103; and a cured product 109 of an epoxy resin composition for sealing the semiconductor element 101 and the copper wire 107. The content of nitrogen contained in the resin substrate 102 is 0.2 to 3.0 mass% (inclusive) based on 100 mass% of organic components contained in the resin substrate 102.

Description

  The present invention relates to a semiconductor device.

  In recent years, copper wires have been proposed as inexpensive bonding wires that replace gold wires.

  Patent Document 1 describes a bonding wire having a core material containing copper as a main component, and an outer skin layer containing copper and a conductive metal different from one or both of the core material and its component or composition on the core material. Has been. In this bonding wire, by making the thickness of the outer skin layer 0.001 to 0.02 μm, the material cost is low, the ball bonding property, the wire bonding property, etc. are excellent, and the loop forming property is also good. It is described that it becomes possible to provide a copper-based bonding wire that can be adapted for thinning a wire and increasing the diameter of a power IC.

JP 2007-12776 A

  However, when the semiconductor element to which the copper wire is connected is sealed with an epoxy resin, the high-temperature storage characteristics (HTSL, High Temperature Storage Life) may not be sufficient. According to the knowledge of the present inventor, such a semiconductor device has an increase in electrical resistance at the junction or disconnection at the junction due to corrosion (oxidation degradation) at the junction between the metal pad on the semiconductor element and the copper wire. Sometimes it could occur. Therefore, it was expected that the high temperature storage property of the semiconductor device could be further improved as compared with the conventional device if the increase in the electrical resistance of the junction part or the possibility of disconnection of the junction part could be prevented.

  Accordingly, the present invention provides a semiconductor device having excellent connection reliability in a high-temperature environment by paying attention to the corrosion (oxidation degradation) of the joint between the metal pad on the semiconductor element and the copper wire when stored at a high temperature. This is the issue.

The present invention
A semiconductor element;
A resin substrate on which the semiconductor element is mounted on at least one surface;
An electrode pad provided in the semiconductor element;
A copper wire connecting the connection terminal provided on the resin substrate and the electrode pad;
A cured body of an epoxy resin composition for sealing the semiconductor element and the copper wire;
With
The present invention provides a semiconductor device in which the nitrogen content contained in the resin substrate is 0.2% by mass or more and 3.0% by mass or less with respect to 100% by mass of the organic component contained in the resin substrate.

  According to this invention, by setting the nitrogen content contained in the resin substrate to 0.2% by mass or more and 3.0% by mass or less, the acidic component resulting from the epoxy resin is contained in the nitrogen contained in the resin substrate. Can be summed. Therefore, it is possible to realize a highly reliable semiconductor device with improved high-temperature storage characteristics by paying attention to the corrosion of the joint between the metal pad and the copper wire.

  According to the present invention, the connection reliability of a semiconductor device in a high temperature environment can be improved.

1 is a cross-sectional view schematically showing a semiconductor device according to an embodiment of the present invention. It is sectional drawing which shows an example of the manufacturing method of the prepreg of embodiment which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate. Also, in the figure, each component schematically shows the shape, size, and arrangement relationship to the extent that the present invention can be understood, and is different from the actual size. In addition, unless otherwise specified, “to” represents the following.

A semiconductor device 100 of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view schematically showing a semiconductor device 100 according to an embodiment of the present invention.
The semiconductor device 100 of the present invention includes a semiconductor element 101, a resin substrate 102 on which at least one surface is mounted with the semiconductor element 101, an electrode pad 103 provided on the semiconductor element 101, and a connection terminal provided on the resin substrate 102. 105 and a copper wire 107 that connects the electrode pad 103 and a cured body 109 of an epoxy resin composition that seals the semiconductor element 101 and the copper wire 107.

In the semiconductor device 100 of the present invention, the nitrogen content contained in the resin substrate 102 is 0.2% by mass or more and 3.0% by mass or less, and preferably 0% with respect to 100% by mass of the organic component contained in the resin substrate 102. It is 0.8 mass% or more and 2.5 mass% or less, More preferably, it is 1.0 mass% or more and 2.2 mass% or less.
Here, the organic component contained in the resin substrate 102 is an organic compound such as a thermosetting resin (A), a coupling agent, a curing accelerator, a curing agent, a thermoplastic resin, or an organic filler described later.
Inorganic components such as the inorganic filler (B), metal circuits such as connection terminals, inorganic fiber base materials such as glass cloth, copper foil, and plated portions are excluded.

The “nitrogen content contained in the resin substrate 102” is specifically measured by the following method. First, four or more portions of the resin substrate 102 are cut out so as not to be biased. Next, the solder resist layer, the hardened body of the sealed epoxy resin composition, and the attached matter such as the copper foil are removed from the cut out sample, and freeze pulverization is performed. The obtained ground sample is mixed well to obtain a ground sample of 300 mg or more. Next, the amount of nitrogen (W ₁ ) in the crushed sample is quantified by the Kjeldahl method shown in JISK6910. Separately, the amount of ash content (W ₂ ) in the pulverized sample is quantified by thermal analysis.
Here, the amount of ash (W ₂ ) was determined by heating the above ground sample from room temperature to 700 ° C. in 30 minutes by thermogravimetry / differential thermal analysis (TG / DTA), and holding at 700 ° C. for 4 hours. It is obtained by measuring the weight of
The measurement sample contains not only organic components but also inorganic components such as glass cloth. Therefore, the weight of the ash content (W ₂₎ was measured, with the exclusion of the weight of the ash from the weight of the measurement sample (W ₀₎ corresponding to the weight of the inorganic component (W _2), the organic components contained in the resin substrate 102 The weight of (W ₀ -W ₂ ) is calculated.
From the following formula (1), the nitrogen content (A) with respect to 100% by mass of the organic component contained in the resin substrate 102 can be calculated.
A (mass%) = 100 × W ₁ / (W ₀ −W ₂ ) (1)

  The nitrogen content contained in the resin substrate 102 of the present invention can be within the above range by adjusting the amount of the nitrogen-containing compound in the resin composition used for the resin substrate 102, for example. The nitrogen-containing compound is not particularly limited as long as it is a nitrogen-containing organic compound, for example, a thermosetting resin such as a triazine skeleton-containing epoxy resin, a cyanate ester resin, a maleimide resin, a benzoxazine resin, a diamine, Examples include aniline resins, triazine skeleton-containing phenol resins, nitrogen-containing curing agents such as dicyandiamide, curing accelerators such as imidazole compounds, nitrogen-containing silane coupling agents such as aminopropyltrialkoxysilane, and the like.

  The semiconductor element 101 is not particularly limited, and examples thereof include an integrated circuit, a large-scale integrated circuit, and a solid-state imaging element.

  The resin substrate 102 is not particularly limited as long as the nitrogen content is within the above range, and is, for example, a circuit substrate. Specifically, a circuit board used in a conventionally known semiconductor device such as a ball grid array (BGA) or a mold array package type BGA (MAP-BGA) can be used.

  The semiconductor element 101 may be a stack of a plurality of semiconductor elements. In this case, the first-stage semiconductor element is bonded to the resin substrate 102 via a die bond material cured body 104 such as a film adhesive or a thermosetting adhesive. The semiconductor elements in the second and subsequent stages can be sequentially laminated with an insulating film adhesive. And the electrode pad 103 is previously formed in the suitable place of each layer by the previous process.

  The electrode pad 103 is preferably made of aluminum (Al) as a main component. The content of Al in the electrode pad 103 is preferably 98% by mass or more with respect to the entire electrode pad 103. Examples of components other than Al contained in the electrode pad 103 include copper (Cu) and silicon (Si). For the electrode pad 103, a general titanium-based barrier layer is formed on the surface of the underlying copper circuit terminal, and a general method for forming an electrode pad of a semiconductor element, such as Al deposition, sputtering, or electroless plating, is applied. Can be produced.

  The copper wire 107 is used to electrically connect the resin substrate 102 and the semiconductor element 101 mounted on the resin substrate 102. An oxide film may be formed on the surface of the copper wire 107 naturally or unavoidably in the process. In the present embodiment, the copper wire 107 includes one having an oxide film formed on the surface of the wire in this way.

  The wire diameter of the copper wire 107 is preferably 30 μm or less, more preferably 25 μm or less, and preferably 15 μm or more. Within this range, the ball shape at the tip of the copper wire is stable, and the connection reliability of the bonding portion can be improved. Further, the wire flow can be reduced by the hardness of the copper wire itself.

  The copper content in the copper wire 107 is preferably 99.9 to 100% by mass, and more preferably 99.99 to 99.999% by mass with respect to the entire copper wire 107. If the copper content is 99.99% by mass or more of the copper wire with respect to the entire copper wire, the ball portion has sufficient flexibility, and there is no risk of damaging the pad side during bonding. Is particularly preferred. The copper wire 107 is ideally made of only copper, but the copper content in the copper wire 107 is practically 99.99999 mass% or less. In addition, the copper wire 107 that can be used in the semiconductor device of the present embodiment is further obtained by doping 0.001 to 0.1% by mass of Ba, Ca, Sr, Be, Al, or rare earth metal into copper as a core wire. Ball shape and joint strength can be improved.

  A ball 111 may be formed at the tip of the copper wire 107 at the joint between the copper wire 107 and the electrode pad 103.

  Moreover, the copper wire 107 may have a coating layer made of a metal material containing palladium on the surface thereof. Thereby, the ball shape at the tip of the copper wire is stabilized, and the connection reliability of the bonding portion can be improved. Moreover, the effect which prevents the oxidation deterioration of copper which is a core wire is also acquired, and the heat resistance of a bonding part can be improved.

  As thickness of the coating layer comprised from the metal material containing palladium in the copper wire 107, it is preferable that it is 0.001-0.02 micrometer, and it is more preferable that it is 0.005-0.015 micrometer. If it is below the above upper limit value, copper as the core wire and metal material containing palladium as the covering material can be sufficiently melted at the time of wire bonding to form a stable ball shape, further improving the heat resistance of the bonding part. Can be made. Moreover, the oxidation deterioration of copper of a core wire can be prevented as it is more than the said lower limit, and the heat resistance of a bonding part can be improved further similarly.

  The copper wire 107 is obtained by casting a copper alloy in a melting furnace, rolling the ingot, performing wire drawing processing using a die, and performing heat treatment after heating while continuously sweeping the wire. Can do. Moreover, the coating layer comprised from the metal material containing palladium in the copper wire 107 which can be used with the semiconductor device 100 prepares the wire of the target wire diameter beforehand, and this is made into the electrolytic solution or electroless solution containing palladium. It is possible to form a coating layer by dipping in the substrate and continuously sweeping and plating. In this case, the thickness of the coating can be adjusted by the sweep rate. Further, a method of preparing a wire thicker than intended, immersing it in an electrolytic solution or an electroless solution, continuously sweeping it to form a coating layer, and drawing the wire to a predetermined diameter can be taken.

Next, an example of a method for manufacturing the semiconductor device 100 will be described.
First, the electrode pad 103 is formed by opening a part of the uppermost protective film 115 of the semiconductor element 101 (the example shown in FIG. 1 shows a buffer coat (protective film) formed) by a known semiconductor manufacturing process. Expose. Next, the semiconductor element 101 provided with the electrode pad 103 is installed on the resin substrate 102 by a further known post-process, and the electrode pad 103 and the connection terminal 105 provided on the resin substrate 102 are wire-bonded by the copper wire 107. .

  Bonding is performed by the following procedure, for example. First, a ball 111 having a predetermined diameter is formed at the tip of the copper wire 107. Next, the ball 111 is lowered substantially perpendicularly to the upper surface of the electrode pad 103, and ultrasonic vibration is applied while the ball 111 and the electrode pad 103 are in contact with each other. As a result, the bottom of the ball 111 comes into contact with the electrode pad 103 to form a bonding surface.

  Note that the connection terminal 105 of the resin substrate 102 and the semiconductor element 101 may be joined by a reverse bond of a wire. In reverse bonding, first, a ball formed at the tip of the copper wire 107 is bonded to the electrode pad 103 on the semiconductor element 101, and the copper wire 107 is cut to form a bump for stitch bonding. Next, a ball formed at the tip of the wire is bonded to the metal-plated connection terminal 105 on the resin substrate 102, and stitch-bonded to the bump of the semiconductor element. In reverse bonding, the height of the wire on the semiconductor element 101 can be made lower than that in the positive bonding, so that the bonding height of the semiconductor element 101 can be reduced.

  Next, an electronic component such as the semiconductor element 101 is sealed using an epoxy resin composition for semiconductor sealing, which will be described later, and is obtained by curing using a conventional molding method such as a transfer mold, a compression mold, or an injection mold. . A semiconductor device sealed by a molding method such as a transfer mold is mounted on an electronic device or the like as it is or after being completely cured at a temperature of about 80 ° C. to 200 ° C. for about 10 minutes to 10 hours. Is done.

  In the semiconductor device 100 manufactured in this way, when heat is applied to the bonding portion during the manufacturing process or use, the metal diffuses from the copper wire 107 to the electrode pad 103 and an alloy layer is formed at the bonding portion between the wire and the pad. However, since the acidic component and oxide component generated from the epoxy resin interacts with nitrogen contained in the resin substrate 102 before reaching the alloy layer, the bonding part is broken due to corrosion (oxidation). Can be prevented. Therefore, according to the present invention, high connection reliability is maintained even when a high temperature process is employed after bonding or when the usage environment is at a high temperature (for example, around an engine such as an automobile). It is possible.

Next, a method for manufacturing the resin substrate 102 according to the present embodiment will be described.
The resin substrate 102 can be obtained, for example, by circuit processing of a cured prepreg including a thermosetting resin, a filler, and a fiber base material.

Here, the manufacturing method of a prepreg is demonstrated.
A prepreg is a sheet-like material provided with a fiber base material and a resin layer obtained by impregnating a fiber base material with one or more resin compositions and then semi-curing the fiber base material. The prepreg used here is a sheet-like material, is excellent in various characteristics such as dielectric characteristics, mechanical and electrical connection reliability under high temperature and high humidity, and is suitable for manufacturing the resin substrate 102 and is preferable.
The method of impregnating the fiber base material with the resin composition is not particularly limited. For example, the resin composition is dissolved in a solvent to prepare a resin varnish, the fiber base material is immersed in the resin varnish, and coating with various coaters. A method of spraying by spraying, a method of laminating a resin layer with a supporting substrate, and the like. Among these, the method of laminating with a film-like resin layer from both sides of the fiber base material is preferable. Thereby, the impregnation amount of the resin composition with respect to the fiber base material can be freely adjusted, and the moldability of the prepreg can be further improved. In addition, when laminating a film-like resin layer, it is more preferable to use a vacuum laminating apparatus or the like.

  A manufacturing process using the laminating method will be described with reference to FIG. FIG. 2 is a process cross-sectional view illustrating an example of a process for manufacturing a prepreg.

  First, carrier material 5a, carrier material 5b, and sheet-like substrate 4 are prepared as materials. Moreover, the vacuum laminating apparatus 1 and the hot air drying apparatus 2 are prepared as an apparatus. The carrier material 5a is composed of a resin layer A obtained from the first resin composition. The carrier material 5b is composed of a resin layer B obtained from the second resin composition. The carrier materials 5a and 5b can be obtained, for example, by a method of applying a resin varnish of the first resin composition and the second resin composition to a carrier film. As the sheet-like substrate 4, for example, a single layer or a fiber substrate in which a plurality of sheets are stacked can be used.

  The solvent used in the resin varnish preferably exhibits good solubility with respect to the resin component in the resin composition, but a poor solvent may be used within a range that does not adversely affect the resin varnish. Examples of the solvent exhibiting good solubility include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, ethylene glycol, cellosolve and carbitol. The details of the first resin composition and the second resin composition will be described later.

  Next, a bonded body is formed by bonding the carrier material 5 a, the sheet-like base material 4, and the carrier material 5 b in this order using the vacuum laminating apparatus 1. The vacuum laminating apparatus 1 includes a roll that winds up the carrier material 5 a, a roll that winds up the carrier material 5 b, a roll that winds up the sheet-like substrate 4, and a laminating roll 7. Under reduced pressure, the carrier material 5 a and the carrier material 5 b fed from each roll are superposed on both surfaces of the sheet-like substrate 4. The stacked laminate is joined by the laminate roll 7. Thereby, the joined body comprised from the carrier material 5a, the sheet-like base material 4, and the carrier material 5b is obtained.

  By joining under reduced pressure, even if there is an unfilled portion in the inside of the sheet-like base material 4 or at the joining portion between each carrier material 5a, 5b and the sheet-like base material 4, this is reduced by a vacuum void or substantially It can be a vacuum void. Therefore, the prepreg 3 finally obtained does not generate voids and can be in a good molded state. This is because the decompression void or the vacuum void can be removed by a heat treatment described later. For such a joining process, other devices such as a vacuum box device can be used.

  Subsequently, using the hot air drying apparatus 2, it heat-processes at the temperature more than the melting temperature of the resin composition which comprises each carrier material 5a, 5b which comprises a conjugate | zygote. Thereby, the decompression void etc. which have occurred in the joining process under reduced pressure can be erased. Other methods of heat treatment can be carried out using, for example, an infrared heating device, a heating roll device, a flat platen hot platen press device, or the like.

  Thus, the prepreg 3 is obtained. In the prepreg 3, the fiber base material may be unevenly distributed in the thickness direction from the center position of the thickness of the resin layer. Such a prepreg 3 can be produced by changing the thickness of the resin layer A and the resin layer B.

  Next, the first resin composition and the second resin composition used in the production of the prepreg (these may be different or the same kind, but are preferably the same kind. These are collectively referred to as the resin composition P hereinafter) Is described in detail. The resin composition P contains, for example, a thermosetting resin (A) and an inorganic filler (B). Hereinafter, each component will be described.

Although it does not specifically limit as a thermosetting resin (A), It has a low linear expansion coefficient and a high elastic modulus, and it is preferable that it is excellent in the reliability of thermal shock property.
Specific thermosetting resins (A) include, for example, phenol novolak resins, cresol novolac resins, bisphenol A novolak resins, triazine skeleton-containing phenol novolak resins, and the like; unmodified resole phenol resins, tung oil, flaxseed Phenol resins such as oil-modified resol phenol resin modified with oil, walnut oil, etc .; bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol E type epoxy resin, bisphenol M Type epoxy resin, bisphenol P type epoxy resin, bisphenol type epoxy resin such as bisphenol Z type epoxy resin; phenol novolac type epoxy resin, cresol novolac Novolac type epoxy resin such as epoxy resin; biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, arylalkylene type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type Epoxy resins such as an epoxy resin, an adamantane type epoxy resin, and a fluorene type epoxy resin; a resin having a triazine ring such as a urea (urea) resin and a melamine resin; an unsaturated polyester resin; a maleimide resin such as a bismaleimide compound; a polyurethane resin; Phthalate resin; silicone resin; benzoxazine resin; cyanate ester resin; polyimide resin; polyamideimide resin; benzocyclobutene resin .
One of these may be used alone, two or more having different weight average molecular weights may be used in combination, and one or two or more thereof and a prepolymer thereof may be used in combination.

  It is preferable that an epoxy resin is included as the thermosetting resin (A). Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, and bisphenol Z type epoxy resin. Bisphenol type epoxy resins; Novolak type epoxy resins such as phenol novolac type epoxy resins and cresol novolac type epoxy resins; Arylalkylene type epoxy resins such as biphenyl type epoxy resins, xylylene type epoxy resins and biphenyl aralkyl type epoxy resins; , Naphthalenediol type epoxy resin, bifunctional or tetrafunctional epoxy type naphthalene resin, naphthylene ether type epoxy resin, binaphthyl type Naphthalene type epoxy resin such as poxy resin, naphthalene aralkyl type epoxy resin; anthracene type epoxy resin; phenoxy type epoxy resin; dicyclopentadiene type epoxy resin; norbornene type epoxy resin; adamantane type epoxy resin; fluorene type epoxy resin; An epoxy resin etc. are mentioned.

  As the epoxy resin, one of these may be used alone, two or more having different weight average molecular weights may be used in combination, and one or two or more thereof and a prepolymer thereof may be used in combination. May be.

  Although content of an epoxy resin is not specifically limited, 1 mass% or more is preferable with respect to the whole resin composition P, and 2 mass% or more is more preferable. When the content of the epoxy resin is not less than the above lower limit, the reactivity of the epoxy resin is improved, and the moisture resistance of the resulting resin substrate 102 can be improved. Moreover, content of an epoxy resin is although it does not specifically limit, 55 mass% or less is preferable with respect to the whole resin composition P, 40 mass% or less is more preferable, and 30 mass% or less is further more preferable. When the content is not more than the above upper limit, the heat resistance of the resin substrate 102 can be further improved.

In addition to using an epoxy resin as the thermosetting resin (A), the resin composition P may use a curing agent such as a phenol resin, an amine curing agent, and dicyandiamide. Particularly preferred are nitrogen-containing phenolic resins such as triazine skeleton-containing phenolic resins, amine curing agents, and dicyandiamide.
Examples of the phenol resin include novolac type phenol resins, resol type phenol resins, aryl alkylene type phenol resins, and triazine skeleton-containing phenol resins. Since the triazine skeleton-containing phenol resin contains nitrogen in particular, the content of nitrogen in the resin substrate 102 can be increased. As a phenol resin, one of these may be used alone, two or more having different weight average molecular weights may be used in combination, and one or two or more thereof and a prepolymer thereof may be used in combination. May be.

  Although content of a phenol resin is not specifically limited, 1 mass% or more is preferable with respect to the whole resin composition P, and 5 mass% or more is more preferable. When the content of the phenol resin is not less than the above lower limit value, the heat resistance of the resin substrate 102 can be further improved. Moreover, although content of a phenol resin is not specifically limited, 40 mass% or less is preferable with respect to the whole resin composition P, 30 mass% or less is more preferable, and 20 mass% or less is further more preferable. When the content of the phenol resin is not more than the above upper limit value, the low thermal expansion characteristic of the resin substrate 102 can be improved.

  The resin composition P preferably contains a cyanate ester resin as the thermosetting resin (A). By using cyanate ester resin, the linear expansion coefficient of the resin substrate 102 can be reduced. Furthermore, when a cyanate ester resin is included, the electrical characteristics (low dielectric constant, low dielectric loss tangent), mechanical strength, and the like of the resin substrate 102 can be improved.

Examples of the cyanate ester resin that can be used include those obtained by reacting a cyanogen halide compound with phenols, and those obtained by prepolymerization by a method such as heating as necessary. Specifically, bisphenol type cyanate ester resins such as novolac type cyanate ester resin, bisphenol A type cyanate ester resin, bisphenol E type cyanate ester resin, tetramethylbisphenol F type cyanate ester resin; and naphthol aralkyl type polyvalent naphthols And cyanate ester resins obtained by reaction with cyanogen halide; dicyclopentadiene type cyanate ester resins; biphenylalkyl type cyanate ester resins. Among these, novolak type cyanate ester resins are preferable. By using the novolac-type cyanate ester resin, the crosslink density is increased and the heat resistance of the resin substrate 102 is improved.
The resin substrate according to the present embodiment preferably contains a predetermined amount of nitrogen due to the nitrogen content contained in the thermosetting resin (A) containing nitrogen or the curing agent. In particular, the effect of the present invention can be further enhanced by including nitrogen by a triazine skeleton-containing epoxy resin, cyanate ester resin, maleimide resin, benzoxazine resin, nitrogen-containing phenol resin, amine curing agent, dicyandiamide, and the like. Is.

  Although content of the thermosetting resin (A) contained in the resin composition P should just be suitably adjusted according to the objective, it is not specifically limited, 5 mass% or more with respect to the whole resin composition P 90 mass % Or less, preferably 10% by mass or more and 80% by mass or less, more preferably 10% by mass or more and 50% by mass or less. When the content of the thermosetting resin is not less than the above lower limit value, handling properties are improved, and it becomes easy to form a prepreg. When the content of the thermosetting resin is not more than the above upper limit value, the strength, flame retardancy, and low thermal expansibility of the resin substrate 102 can be improved.

  The resin composition P used for the prepreg preferably contains an inorganic filler (B) in addition to the thermosetting resin (A). Thereby, even if the resin substrate 102 is thinned, it is possible to impart even better mechanical strength. In addition, the thermal expansion of the resin substrate 102 can be further improved.

  Examples of the inorganic filler (B) include silicates such as talc, fired clay, unfired clay, mica and glass; oxides such as titanium oxide, alumina, boehmite, silica and fused silica; calcium carbonate and magnesium carbonate Carbonates such as hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide; sulfates or sulfites such as barium sulfate, calcium sulfate and calcium sulfite; zinc borate, barium metaborate, Borates such as aluminum borate, calcium borate and sodium borate; nitrides such as aluminum nitride, boron nitride, silicon nitride and carbon nitride; titanates such as strontium titanate and barium titanate; Can do.

  As the inorganic filler (B), one of these may be used alone, or two or more may be used in combination. Among these, silica is particularly preferable. Silica has a crushed shape and a spherical shape. In order to ensure high filling of the inorganic filler (B), it is possible to adopt a usage method suited to the purpose, such as using spherical silica to lower the melt viscosity of the resin composition P.

  Although content of an inorganic filler (B) is not specifically limited, 20 mass% or more and 80 mass% or less are preferable with respect to the whole resin composition P, and 30 mass% or more and 75 mass% or less are more preferable. When the content is within the above range, the resin substrate 102 can have particularly low thermal expansion and low water absorption.

  In addition, additives such as a coupling agent, a curing accelerator, a curing agent, a thermoplastic resin, and an organic filler can be appropriately added to the resin composition P as necessary. The resin composition P used in the present embodiment can be suitably used in a liquid form in which the above components are dissolved and / or dispersed with an organic solvent or the like.

  By using the coupling agent, the wettability of the interface between the thermosetting resin (A) and the inorganic filler (B) can be improved. Therefore, it is preferable to use a coupling agent, and the heat resistance of the resin substrate 102 can be improved.

  As the coupling agent, any of those usually used as a coupling agent can be used. Specifically, an epoxy silane coupling agent, a cationic silane coupling agent, an aminosilane coupling agent, a titanate coupling agent, and silicone. It is preferable to use one or more coupling agents selected from oil-type coupling agents. Thereby, wettability with the interface of an inorganic filler (B) can be made high, and, thereby, heat resistance can be improved more.

  The addition amount of the coupling agent is not particularly limited because it depends on the specific surface area of the inorganic filler (B), but is preferably 0.05 parts by mass or more with respect to 100 parts by mass of the inorganic filler (B). Part by mass or more is preferable. When the content of the coupling agent is not less than the above lower limit, the inorganic filler (B) can be sufficiently covered, and the heat resistance of the resin substrate 102 can be improved. Moreover, although the addition amount of a coupling agent is not specifically limited, 3 mass parts or less are preferable and 2 mass parts or less are more preferable. When the content is not more than the above upper limit value, it is possible to suppress the influence on the reaction, and it is possible to suppress a decrease in the bending strength or the like of the resin substrate 102.

  A well-known thing can be used as a hardening accelerator. For example, organic metal salts such as zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), trisacetylacetonate cobalt (III); triethylamine, tributylamine, diazabicyclo [2, 2,2] tertiary amines such as octane; 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 2-ethyl-4-ethylimidazole, 2-phenyl-4-ethylimidazole, 2- Imidazoles such as phenyl-4-methyl-5-hydroxyimidazole and 2-phenyl-4,5-dihydroxyimidazole; phenolic compounds such as phenol, bisphenol A and nonylphenol; acetic acid, benzoic acid, salicylic acid, paratoluenesulfonic acid Which organic acid; onium salt compounds; and the like. As the curing accelerator, one kind including these derivatives may be used alone, or two or more kinds including these derivatives may be used in combination.

  Although content of a hardening accelerator is not specifically limited, 0.01 mass% or more and 5 mass% or less are preferable with respect to the whole resin composition P, and 0.1 mass% or more and 2 mass% or less are more preferable. When the content of the curing accelerator is not less than the above lower limit, the effect of promoting curing can be sufficiently exerted. When the content of the curing accelerator is not more than the above upper limit value, the storability of the resin substrate 102 can be further improved.

  The resin composition P in this embodiment is a thermoplastic resin such as phenoxy resin, polyimide resin, polyamideimide resin, polyphenylene oxide resin, polyethersulfone resin, polyester resin, polyethylene resin, polystyrene resin; styrene-butadiene copolymer, Polystyrene thermoplastic elastomers such as styrene-isoprene copolymers; Polyolefin thermoplastic elastomers; Thermoplastic elastomers such as polyamide elastomers and polyester elastomers; Dienes such as polybutadiene, epoxy-modified polybutadiene, acrylic-modified polybutadiene, and methacryl-modified polybutadiene An elastomer may be further used in combination.

  Examples of the phenoxy resin include a phenoxy resin having a bisphenol skeleton, a phenoxy resin having a naphthalene skeleton, a phenoxy resin having an anthracene skeleton, and a phenoxy resin having a biphenyl skeleton (also referred to as a biphenyl phenoxy resin). A phenoxy resin having a structure having a plurality of these skeletons can also be used.

  If necessary, additives other than the above components such as pigments, dyes, antifoaming agents, leveling agents, ultraviolet absorbers, foaming agents, antioxidants, flame retardants, and ion scavengers are added to the resin composition P. May be.

  Although it does not specifically limit as a fiber base material used for this embodiment, From glass fiber base materials, such as glass cloth, a polybenzoxazole resin fiber, a polyamide resin fiber, an aromatic polyamide resin fiber, a wholly aromatic polyamide resin fiber, etc. It is composed of at least one of polyester resin fibers, polyimide resin fibers, and fluororesin fibers selected from selected polyamide resin fibers, polyester resin fibers, aromatic polyester resin fibers, wholly aromatic polyester resin fibers, and the like. Synthetic fiber base materials, craft paper, cotton linter paper, organic fiber base materials such as paper base materials mainly containing any one or more of linter and kraft pulp mixed paper. Among these, a glass fiber substrate is particularly preferable from the viewpoint of strength and water absorption. Moreover, the thermal expansion coefficient of the resin substrate 102 can be further reduced by using the glass fiber base material.

  Subsequently, the resulting prepreg is laminated by heating and pressing in a configuration in which a metal foil layer is disposed on one or both sides of the prepreg. Thereby, a metal-clad laminate is obtained. Carrier foil may be provided on the surface of the metal foil layer.

Next, through holes for interlayer connection are formed in the metal-clad laminate, and a wiring layer is produced by a subtractive method, a semi-additive method, or the like. Thereafter, build-up layers are laminated as necessary, and the steps of interlayer connection and circuit formation by the additive method are repeated. Then, if necessary, a solder resist layer is laminated, and a circuit is formed by a method according to the above, whereby the resin substrate 102 is obtained. Here, a part or all of the buildup layer and the solder resist layer may or may not include a fiber base material.
Alternatively, the connection terminals 119 may be provided on the resin substrate 102 and the solder bumps 117 may be mounted on the connection terminals 119.

Next, the epoxy resin composition for semiconductor encapsulation according to this embodiment will be described.
The epoxy resin composition for semiconductor encapsulation according to this embodiment includes (A) an epoxy resin and (B) a curing agent, and encapsulates the copper wire 107 and the semiconductor element 101 to which the copper wire 107 is connected. An epoxy resin composition for stopping.

(A) The epoxy resin is a monomer, oligomer, or polymer in general having two or more epoxy groups in one molecule, and its molecular weight and molecular structure are not particularly limited. For example, bisphenol A type epoxy resin, Bisphenol type epoxy resin such as bisphenol F type epoxy resin, tetramethylbisphenol F type epoxy resin, biphenyl type epoxy resin, stilbene type epoxy resin; Novolak type epoxy resin such as phenol novolac type epoxy resin and cresol novolac type epoxy resin; Polyfunctional epoxy resins such as methane type epoxy resins and alkyl-modified triphenol methane type epoxy resins; phenol aralkyl type epoxy resins having a phenylene skeleton, phenol aralkyl types having a biphenylene skeleton Aralkyl-type epoxy resins such as poxy resins; Dihydroxynaphthalene-type epoxy resins, naphthol-type epoxy resins such as epoxy resins obtained by glycidyl etherification of dihydroxynaphthalene dimers; Triglycidyl isocyanurate, monoallyl diglycidyl isocyanurate, etc. Triazine nucleus-containing epoxy resins; bridged cyclic hydrocarbon compound-modified phenolic epoxy resins such as dicyclopentadiene-modified phenolic epoxy resins, and the like. These may be used alone or in combination of two or more. .
The bisphenol type epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethyl bisphenol F type epoxy resin, biphenyl type epoxy resin, and stilbene type epoxy resin preferably have crystallinity.

  Preferably, (A) the epoxy resin represented by the following formula (1), the epoxy resin represented by the following formula (2), and the epoxy resin represented by the following formula (3) are used as the epoxy resin. What contains at least 1 sort (s) selected from can be used.

In Formula (1), Ar ¹ represents a phenylene group or a naphthylene group, and when Ar ¹ is a naphthylene group, the glycidyl ether group may be bonded to either the α-position or the β-position, Ar ² represents a phenylene group, It represents any one of a biphenylene group and a naphthylene group, R ⁵ and R ⁶ each independently represent a hydrocarbon group having 1 to 10 carbon atoms, g is an integer of 0 to 5, and h is 0 8 is an integer, ^{n 3} represents a polymerization degree, the average value is 1-3.

In Formula (2), a plurality of R ^9s each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, n ⁵ represents a degree of polymerization, and an average value thereof is 0 to 4.

In formula (3), a plurality of R ¹⁰ and R ¹¹ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, n ⁶ represents a degree of polymerization, and an average value thereof is 0 to 4. .

  (A) The content of the epoxy resin is preferably 3% by mass or more, and more preferably 5% by mass or more with respect to the entire epoxy resin composition. By doing so, the possibility of causing wire breakage due to an increase in viscosity can be reduced. Moreover, it is preferable that it is 18 mass% or less with respect to the whole epoxy resin composition, as for content of an epoxy resin (A), it is more preferable that it is 13 mass% or less, and 11 mass% or less is further more preferable. By doing so, it is possible to reduce the possibility of causing a decrease in moisture resistance reliability due to an increase in water absorption.

  (B) As a hardening | curing agent, it can divide roughly into three types, for example, a polyaddition type hardening | curing agent, a catalyst type hardening | curing agent, and a condensation type hardening | curing agent.

  Examples of polyaddition type curing agents include aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), and metaxylylene diamine (MXDA), diaminodiphenylmethane (DDM), and m-phenylenediamine (MPDA). In addition to aromatic polyamines such as diaminodiphenylsulfone (DDS), polyamine compounds including dicyandiamide (DICY), organic acid dihydrazide, etc .; alicyclics such as hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride (MTHPA) Acid anhydrides, including acid anhydrides, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), aromatic anhydrides such as benzophenone tetracarboxylic acid (BTDA); novolac-type phenolic resin, polyvinyl Phenolic resin curing agent such as phenol; polysulfide, thioester, polymercaptan compounds such as thioethers; isocyanate prepolymer, isocyanate compounds such as blocked isocyanate; and organic acids such as carboxylic acid-containing polyester resins.

Examples of the catalyst-type curing agent include tertiary amine compounds such as benzyldimethylamine (BDMA) and 2,4,6-trisdimethylaminomethylphenol (DMP-30); 2-methylimidazole, 2-ethyl-4 -Imidazole compounds such as methylimidazole (EMI24); Lewis acids such as BF ₃ complexes.

  Examples of the condensation type curing agent include a resol type phenol resin; a urea resin such as a methylol group-containing urea resin; and a melamine resin such as a methylol group-containing melamine resin.

  Among these, a phenol resin-based curing agent is preferable from the viewpoint of balance of flame resistance, moisture resistance, electrical characteristics, curability, storage stability, and the like. The phenol resin-based curing agent is a monomer, oligomer, or polymer in general having two or more phenolic hydroxyl groups in one molecule, and its molecular weight and molecular structure are not particularly limited. For example, phenol novolak resin, cresol novolak Resin, novolak type resin such as bisphenol novolac; polyfunctional phenol resin such as triphenolmethane type phenol resin; modified phenol resin such as terpene modified phenol resin and dicyclopentadiene modified phenol resin; phenylene skeleton and / or biphenylene skeleton Aralkyl type resins such as phenol aralkyl resins, naphthol aralkyl resins having a phenylene and / or biphenylene skeleton; bisphenol compounds such as bisphenol A and bisphenol F, etc. Type may be used in combination of two or more be used alone.

  Preferably, as the (B) curing agent, at least one curing agent selected from the group consisting of compounds represented by the following formula (4) can be used.

In formula (4), Ar ³ represents a phenylene group or a naphthylene group, and when Ar ³ is a naphthylene group, the hydroxyl group may be bonded to either the α-position or the β-position, and Ar ⁴ represents a phenylene group or a biphenylene group. And any one of naphthylene groups, R ⁷ and R ⁸ each independently represents a hydrocarbon group having 1 to 10 carbon atoms, i is an integer of 0 to 5, and j is 0 to 8 N ⁴ represents the degree of polymerization, and the average value is 1 to 3.

  (B) Content of a hardening | curing agent is 2 mass% or more in an epoxy resin composition, It is more preferable that it is 3 mass% or more, It is further more preferable that it is 4 mass% or more. By doing so, sufficient fluidity can be obtained. In addition, the content of the (B) curing agent in the epoxy resin composition is preferably 15% by mass or less, more preferably 11% by mass or less, and further preferably 8% by mass or less. . By doing so, it is possible to reduce the possibility of causing a decrease in moisture resistance reliability due to an increase in water absorption.

  In addition, when (B) a phenol resin curing agent is used as the curing agent, the blending ratio of the epoxy resin and the phenol resin curing agent is the number of epoxy groups (EP) of all epoxy resins and the phenol of all phenol resin curing agents. It is preferable that equivalence ratio (EP) / (OH) with the number of functional hydroxyl groups (OH) is 0.8 to 1.3. When the equivalent ratio is within this range, there is little possibility of causing a decrease in the curability of the epoxy resin composition or a decrease in the physical properties of the resin cured product.

  The epoxy resin composition may contain (C) a filler and (D) a curing accelerator.

  (C) As a filler, what is used for the general epoxy resin composition for semiconductor sealing can be used. Examples thereof include inorganic fillers such as fused spherical silica, fused crushed silica, crystalline silica, talc, alumina, titanium white, and silicon nitride, and organic fillers such as organosilicone powder and polyethylene powder. preferable. These fillers may be used alone or in combination of two or more. The shape of the filler (C) is as spherical as possible and the particle size distribution is broad in order to suppress an increase in the melt viscosity of the epoxy resin composition and further increase the filler content. Is preferred. The filler may be surface-treated with a coupling agent. Furthermore, if necessary, the filler may be pre-treated with an epoxy resin or a phenol resin, and the treatment method includes a method of removing the solvent after mixing with a solvent, or a direct addition to the filler. In addition, there is a method of mixing using a mixer.

  (C) The content of the filler is preferably 65% by mass or more, and 75% by mass or more with respect to the entire epoxy resin composition, from the viewpoint of the filling property of the epoxy resin composition and the reliability of the semiconductor device. More preferably, it is more preferably 80% by mass or more. By doing so, low moisture absorption and low thermal expansion can be obtained, so that the risk of insufficient moisture resistance reliability can be reduced. In addition, the content of the filler (C) is preferably 93% by mass or less, more preferably 91% by mass or less, and more preferably 90% by mass with respect to the entire epoxy resin composition in consideration of moldability. % Or less is more preferable. By doing so, it is possible to reduce the possibility that fluidity is lowered and poor filling or the like occurs during molding, or inconvenience such as wire flow in the semiconductor device due to high viscosity.

  The (D) curing accelerator only needs to accelerate the crosslinking reaction between the epoxy group of the epoxy resin and the curing agent (for example, the phenolic hydroxyl group of the phenol resin-based curing agent). What is used for a composition can be used. For example, bicyclic amidines such as 1,8-diazabicyclo (5,4,0) undecene-7 and derivatives thereof, monocyclic amidines such as 2-methylimidazole; organic phosphines such as triphenylphosphine and methyldiphenylphosphine Quaternary phosphonium salts such as tetraphenylphosphonium and tetraphenylborate; adducts of a phosphine compound and a quinone compound, and the like. These may be used alone or in combination of two or more.

  (D) It is preferable that content of a hardening accelerator is 0.05 mass% or more with respect to the whole epoxy resin composition, and it is more preferable that it is 0.1 mass% or more. By doing so, the possibility of causing a decrease in curability can be reduced. Moreover, it is preferable that it is 1 mass% or less with respect to the whole epoxy resin composition, and, as for content of (E) hardening accelerator, it is more preferable that it is 0.5 mass% or less. By doing so, the possibility of causing a decrease in fluidity can be reduced.

  If necessary, the epoxy resin composition further includes neutralizing agents such as calcium carbonate, calcium borate, calcium metasilicate, aluminum hydroxide, boehmite; corrosion inhibitors such as hydrotalcite, magnesium oxide, magnesium carbonate; Inorganic ion exchangers such as bismuth hydrate; coupling agents such as epoxy silane, γ-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane; carbon black, bengara, etc. Coloring agents; Low stress components such as silicone rubber; Natural waxes such as carnauba wax; Synthetic waxes; Mold release agents such as higher fatty acids such as zinc stearate and their metal salts or paraffin; Aluminum hydroxide, magnesium hydroxide, boron Zinc acid, molybdic acid Lead, flame retardants such as phosphazene, various additives such as an antioxidant may be appropriately blended.

  The epoxy resin composition is obtained by mixing the above-mentioned components at 15 ° C. to 28 ° C. using, for example, a mixer, and then melt-kneading with a kneader such as a roll, a kneader, or an extruder, and grinding after cooling. Those having an appropriate degree of dispersion and fluidity can be used as necessary.

  The cured body of the epoxy resin composition for semiconductor encapsulation of the present invention can be obtained by molding and curing the above epoxy resin composition by a conventional molding method such as transfer molding, compression molding, injection molding or the like. The cured product of the epoxy resin composition molded and cured by a molding method such as transfer mold is completely cured at a temperature of about 80 ° C. to 200 ° C. for about 10 minutes to 24 hours as necessary. It can also be obtained.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to these. In addition, in an Example, unless otherwise specified, a part represents a mass part.

In the examples and comparative examples, the following raw materials were used.
Epoxy resin BA: Biphenylene skeleton-containing phenol aralkyl epoxy resin (Nippon Kayaku Co., Ltd., NC-3000)
Epoxy resin C: naphthalenediol diglycidyl ether (manufactured by DIC, Epicron HP-4032D)
Epoxy resin D: naphthylene ether type epoxy resin (DIC Corporation, Epicron HP-6000)

Cyanate ester resin A: Novolak-type cyanate ester resin (Lonza Japan, Primaset PT-30)
Cyanate ester resin B: p-xylene-modified naphthol aralkyl type cyanate ester resin represented by the following general formula (II) (naphthol aralkyl type phenol resin (manufactured by Toto Kasei Co., Ltd., “SN-485 derivative”)) and a reaction product of cyanogen chloride )

（式中、Ｒは水素原子またはメチル基を示し、ｎは１以上の整数を示す。）

(In the formula, R represents a hydrogen atom or a methyl group, and n represents an integer of 1 or more.)

Phenol resin A: Biphenyl dimethylene type phenol resin (manufactured by Nippon Kayaku Co., Ltd., GPH-103)
Amine compound: 4,4′-diaminodiphenylmethane bismaleimide compound (manufactured by KAI Kasei Kogyo Co., Ltd., BMI-70)

Phenoxy resin A: Phenoxy resin containing a bisphenol acetophenone structure (YX-6654BH30, manufactured by Mitsubishi Chemical Corporation)

Filler A: Spherical silica (manufactured by Admatechs, SO-25R, average particle size 0.5 μm)
Filler B: Spherical silica (manufactured by Admatechs, SO-31R, average particle size 1.0 μm)
Filler C: Spherical silica (manufactured by Tokuyama, NSS-5N, average particle size 75 nm)
Filler D: Boehmite (Navaltech AOH-30)
Filler E: Silicone particles (Shin-Etsu Chemical Co., Ltd., KMP-600, average particle size 5 μm)

Coupling agent A: γ-glycidoxypropyltrimethoxysilane (GE Toshiba Silicone, A-187)
Curing accelerator A: Phosphorus catalyst of an onium salt compound corresponding to the following general formula (IX) (manufactured by Sumitomo Bakelite, #C)

(In the formula, P represents a phosphorus atom, R ¹ , R ² , R ³ and R ⁴ each represents an organic group having a substituted or unsubstituted aromatic ring or heterocyclic ring, or a substituted or unsubstituted aliphatic group. A ⁻ may be the same as or different from each other, and A ⁻ is an anion of an n (n ≧ 1) -valent proton donor having at least one proton that can be released to the outside of the molecule, or a complex anion thereof. Is shown.)

Curing accelerator B: Zinc octylate

Example 1
Preparation of Resin Varnish 1 11.0 parts by mass of a biphenylene skeleton-containing phenol aralkyl epoxy resin (Nippon Kayaku Co., Ltd., NC-3000) as an epoxy resin BA, 3.5 parts by mass of 4,4′-diaminodiphenylmethane as an amine compound, bis As a maleimide compound, 20.0 parts by mass of bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane (manufactured by Keiai Chemical Industry Co., Ltd., BMI-70) was dissolved and dispersed in methyl ethyl ketone. Furthermore, 20.0 parts by mass of spherical silica (manufactured by Admatechs, SO-25R, average particle size 0.5 μm) as filler A, and 45.0 masses of boehmite (manufactured by Navaltech, AOH-30) as filler D And 0.5 parts by mass of γ-glycidoxypropyltrimethoxysilane (GE Toshiba Silicone Co., Ltd., A-187) is added as a coupling agent A, and the mixture is stirred for 30 minutes using a high-speed stirrer. The resin varnish 1 was prepared by adjusting the content to 65% by mass.

Production of carrier material Resin varnish 1 is dried onto a support substrate ultrathin copper foil with carrier foil (manufactured by Mitsui Kinzoku Mining Co., Ltd., Micro Thin Ex, 1.5 μm) using a die coater device. The film was coated to a thickness of 30 μm and dried for 5 minutes with a dryer at 160 ° C. to obtain a resin sheet 1A with a copper foil (carrier material 1A) for the first resin layer.
Also, the resin varnish 1 is applied in the same manner onto an ultrathin copper foil with carrier foil (Mitsui Metal Mining Co., Ltd., Microcin Ex, 1.5 μm), and the thickness of the resin layer after drying is 30 μm. And drying for 5 minutes with a dryer at 160 ° C. to obtain a resin sheet 1B with copper foil (carrier material 1B) for the second resin layer.

Manufacture of prepreg (prepreg 1)
The carrier material 1A for the first resin layer and the carrier material 1B for the second resin layer are made of a fiber layer on both sides of a glass fiber substrate (T glass woven fabric manufactured by Nittobo, WTX-116E, IPC standard 2116T). Arranged so as to face the substrate, the resin composition was impregnated with a vacuum laminating apparatus and a hot air drying apparatus shown in FIG. 2 to obtain a prepreg 1 on which a copper foil was laminated.
Specifically, the carrier material A and the carrier material B are overlapped on both surfaces of the glass fiber base so that they are positioned at the center in the width direction of the glass fiber base, respectively, and 9.999 × 10 ⁴ Pa (from normal pressure) Under a condition where the pressure was reduced by about 750 Torr) or more, the laminating speed was set to 2 m / min, the tension applied to the glass fiber substrate was set to 140 N / m, and bonding was performed using a 100 ° C. laminating roll.
Here, in the inner region of the width direction dimension of the glass fiber base material, the resin layers of the carrier material 1A and the carrier material 1B are respectively bonded to both sides of the glass fiber base material, and the width direction dimension of the glass fiber base material In the outer region, the resin layers of the carrier material 1A and the carrier material 1B were joined together.
Next, the bonded product was heat-treated without applying pressure by passing it through a horizontal conveyance type hot air drying apparatus set at 120 ° C. for 2 minutes to obtain a prepreg 1.

Production of metal-clad laminate A prepreg 1 on which a copper foil was laminated was sandwiched between smooth metal plates and heated and pressed at 220 ° C. and 1.5 MPa for 2 hours to obtain a metal-clad laminate.

Production of Circuit Board Using the metal-clad laminate obtained above as a core board, an inner circuit board was formed by patterning on both sides thereof by a semi-additive method. A resin sheet with a copper foil (carrier material 1A) was laminated on both surfaces by vacuum lamination, and then heat-cured at 220 ° C. for 60 minutes with a hot air dryer. Next, after peeling off the carrier foil, blind via holes (non-through holes) were formed by a carbonic acid laser. Next, the inside of the via is immersed in a 60 ° C. swelling liquid (Atotech Japan Co., Swelling Dip Securigant P) for 5 minutes, and further an 80 ° C. potassium permanganate aqueous solution (Atotech Japan Co., Concentrate Compact CP). After 10 minutes of immersion, the mixture was neutralized and roughened.
This was subjected to degreasing, catalyst application, and activation steps, a plating resist was formed, and circuit processing was performed using an electroless copper plating film as a power feeding layer. Next, after performing an annealing process at 200 ° C. for 60 minutes with a hot air drying apparatus, the power feeding layer was removed by flash etching.
Next, a solder resist layer was laminated, and then blind via holes (non-through holes) were formed by a carbonic acid laser so that the semiconductor element mounting die pad and the like were exposed.
Finally, a plating layer composed of an electroless nickel plating layer and an electroless gold plating layer is formed on the circuit layer exposed from the solder resist layer, and the obtained substrate is cut into a size of 187 mm × 50 mm, Got.

<Nitrogen content in circuit board>
Four or more portions of the obtained circuit board were cut out so as not to be biased. Next, deposits such as a solder resist layer and a plating layer were removed from the cut sample, and freeze pulverization was performed. The obtained ground sample was mixed well to obtain a ground sample of 300 mg or more. Next, the amount (W ₁ ) of nitrogen in the ground sample was quantified by the Kjeldahl method shown in JISK6910. The amount of ash in the crushed sample (W ₂ ) is determined by heating the crushed sample from room temperature to 700 ° C. in 30 minutes by thermogravimetry / differential thermal analysis (TG / DTA) and holding at 700 ° C. for 4 hours. And obtained by measuring the weight of the residue.
The measurement sample contains not only organic components but also inorganic components such as glass cloth. Therefore, the weight (W ₂ ) of the ash is measured, the weight (W ₂ ) of the ash corresponding to the weight of the inorganic component is excluded from the weight (W ₀ ) of the measurement sample, and the organic component contained in the circuit board is removed. Calculate the weight (W ₀ -W ₂ ).
The nitrogen content (A) relative to 100% by mass of the organic component contained in the circuit board was calculated from the following equation (1).
A (mass%) = 100 × W ₁ / (W ₀ −W ₂ ) (1)
The obtained values are shown in Table 1.

Each component shown in Table 2 was mixed at 15 to 28 ° C. using a mixer for manufacturing an epoxy resin composition for semiconductor encapsulation , and then roll-kneaded at 70 to 100 ° C. After cooling, it was pulverized to obtain an epoxy resin composition. In Table 2, the details of each component are as follows. Moreover, the unit in Table 2 is mass%.

<(A) Epoxy resin>
Epoxy resin BA: Biphenylene skeleton-containing phenol aralkyl epoxy resin (Nippon Kayaku Co., Ltd., NC-3000)

<(B) Curing agent>
Curing agent BA: MEH-7785SS, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 203

<(C) Filler>
Silica: FB-820, manufactured by Denki Kagaku Kogyo Co., Ltd., fused spherical silica, average particle size of 26.5 μm, particles of 105 μm or more 1% or less

<(D) Curing accelerator>
Triphenylphosphine (TPP), manufactured by Hokuko Chemical Co., Ltd.

<Other ingredients>
Coupling agent: 3-mercaptopropylmethyldimethoxysilane Colorant: Carbon black mold release agent: Carnauba wax corrosion inhibitor: Hydrotalcite (DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.)

  The physical properties of the epoxy resin composition were measured by the following methods. The results are shown in Table 2.

<Spiral flow (SF)>
Using a low-pressure transfer molding machine (“KTS-15” manufactured by Kotaki Seiki Co., Ltd.), a mold for spiral flow measurement in accordance with EMMI-1-66, mold temperature 175 ° C., injection pressure 6.9 MPa, curing time The epoxy resin composition was injected under the condition of 120 seconds, and the flow length (unit: cm) was measured.

<Geltime (GT)>
After melting the epoxy resin composition on a hot plate heated to 175 ° C., the time (unit: second) until it was cured while kneading with a spatula was measured.

Manufacturing of Semiconductor Device A TEG (TEST ELEMENT GROUP) chip (3.5 mm × 3.5 mm) having an aluminum electrode pad (aluminum purity 99.9 mass%, thickness 1 μm) is bonded to the die pad portion of the circuit board, and the TEG Wire bonding was performed using a copper wire (copper purity 99.99 mass%, diameter 25 μm) at a wire pitch of 80 μm so that the electrode pad of the chip and the electrode pad of the substrate were connected in a daisy chain. Using a low-pressure transfer molding machine (“Y series” manufactured by TOWA), this was sealed using the above epoxy resin composition under conditions of a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 2 minutes. A semiconductor package was manufactured. After the package was post-cured at 175 ° C. for 4 hours, a semiconductor device was obtained.

<Nitrogen content in circuit boards in semiconductor devices>
Four or more circuit boards in the obtained semiconductor device were cut out so as not to be biased. Next, the solder resist layer, the cured cured epoxy resin composition, and the deposits such as the plating layer were removed from the cut out sample, and freeze pulverization was performed. The obtained ground sample was mixed well to obtain a ground sample of 300 mg or more. Next, the amount (W ₁ ) of nitrogen in the ground sample was quantified by the Kjeldahl method shown in JISK6910. The amount of ash in the crushed sample (W ₂ ) is determined by heating the crushed sample from room temperature to 700 ° C. in 30 minutes by thermogravimetry / differential thermal analysis (TG / DTA) and holding at 700 ° C. for 4 hours. And obtained by measuring the weight of the residue.
The measurement sample contains not only organic components but also inorganic components such as glass cloth. Therefore, the weight (W ₂ ) of the ash is measured, the weight (W ₂ ) of the ash corresponding to the weight of the inorganic component is excluded from the weight (W ₀ ) of the measurement sample, and the organic component contained in the circuit board is removed. Calculate the weight (W ₀ -W ₂ ).
The nitrogen content (A) relative to 100% by mass of the organic component contained in the circuit board was calculated from the following equation (1).
A (mass%) = 100 × W ₁ / (W ₀ −W ₂ ) (1)
It was confirmed that the nitrogen content of the circuit board in the obtained semiconductor device was almost the same value as the nitrogen content contained in the circuit board.

<High temperature storage characteristics>
The obtained semiconductor device was subjected to HTSL (high temperature storage test) of the semiconductor device. Specifically, the treatment was performed at 200 ° C., and the time during which defects occurred was examined. The determination of the defect was evaluated using 10 manufactured packages, and the time when the package in which the resistance value after the treatment with respect to the initial resistance exceeded 1.2 times was defined as the defect time. The results are shown in Table 2. The unit in Table 2 is time.

(Examples 2 to 4, Comparative Examples 1 and 2)
A semiconductor device was prepared in the same manner as in Example 1 except that the composition of the resin varnish was changed to the composition shown in Table 1 and the composition of the epoxy resin composition for semiconductor encapsulation was changed to the composition shown in Table 2. I did it.

DESCRIPTION OF SYMBOLS 1 Vacuum laminating apparatus 2 Hot air drying apparatus 3 Prepreg 4 Sheet-like base material 5a Carrier material 5b Carrier material 7 Laminate roll 100 Semiconductor device 101 Semiconductor element 102 Resin substrate 103 Electrode pad 104 Die bond material hardening body 105 Connection terminal 107 Copper wire 109 Epoxy resin Cured body of composition 111 Ball 115 Protective film 117 Solder bump 119 Connection terminal

Claims (6)

A semiconductor element;
A resin substrate on which the semiconductor element is mounted on at least one surface;
An electrode pad provided in the semiconductor element;
A copper wire connecting the connection terminal provided on the resin substrate and the electrode pad;
A cured body of an epoxy resin composition that seals the semiconductor element and the copper wire;
With
The semiconductor device whose nitrogen content contained in the said resin substrate is 0.2 to 3.0 mass% with respect to 100 mass% of organic components contained in the said resin substrate. The semiconductor device according to claim 1,
The said resin substrate is a semiconductor device containing a thermosetting resin, a filler, and a fiber base material. The semiconductor device according to claim 1 or 2,
The resin substrate contains one or more nitrogen atoms selected from the group consisting of triazine skeleton-containing epoxy resins, cyanate ester resins, triazine skeleton-containing phenol resins, maleimide resins, benzoxazine resins, amine curing agents, and dicyandiamide. A semiconductor device comprising a cured product of a resin composition containing a compound. The semiconductor device according to any one of claims 1 to 3,
The semiconductor device whose copper content in the said copper wire is 99.99 mass% or more with respect to the said whole copper wire. The semiconductor device according to any one of claims 1 to 4,
A semiconductor device, wherein the electrode pad contains aluminum as a main component. The semiconductor device according to claim 1,
A semiconductor device, wherein the resin substrate is a circuit board.

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