JP2006249377A - Resin composition for sealing semiconductor and semiconductor device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for sealing semiconductor excellent not only in safety, but also in moisture resistant reliability, flame retardancy, moldability, and mold releasability. <P>SOLUTION: The resin composition for sealing semiconductor containing the following components (A) to (E), wherein the content of the component (B) is in the range of 5-30 wt% of the whole resin composition, and the total content of the component (B) and the component (C) is in a range of 60-90 wt% of the whole resin composition. (A) is a thermosetting resin composition. (B) is a metal compound which releases water or carbon dioxide in a 200-400°C range. (C) is an inorganic filler excluding the metal compound which belongs to the component (B). (D) is a mold release agent having an acid value of 1 to below 10. (E) is a mold release agent having an acid value of 10-20 and an average number of acidic groups in a molecule of in a range of 0.1-0.3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin composition for encapsulating a semiconductor excellent in flame retardancy, solder resistance, moisture resistance reliability, fluidity and releasability, and a semiconductor device using the same.

  Conventionally, semiconductor elements such as transistors, ICs, and LSIs have been encapsulated with ceramics or the like to form semiconductor devices, but recently, resin encapsulation using plastic has become mainstream from the viewpoint of cost and mass productivity. ing. An epoxy resin composition has been conventionally used for this type of resin sealing, and has achieved good results. However, technological innovations in the semiconductor field have led to improvements in the degree of integration, increasing device size and wiring, and packages tend to be smaller and thinner. There is a demand for further improvement in reliability.

  On the other hand, it is indispensable for electronic components such as semiconductor devices to conform to UL94 V-0, which is a flame retardant standard, and conventionally, a method of imparting flame retardancy to a resin composition for semiconductor encapsulation. In general, a method of adding a brominated epoxy resin, antimony trioxide, or the like is generally performed.

However, there were two major problems related to the above-mentioned flame retardancy imparting technology.
The first problem is the harmfulness of antimony trioxide itself, the harmfulness to the human body due to the generation of hydrogen bromide, bromine gas, antimony bromide during combustion, and the corrosiveness to equipment. It was.

  As a second problem, if a semiconductor device adopting the above-mentioned flame retarding technology is left at high temperature for a long time, the aluminum wiring on the semiconductor element is corroded by the influence of liberated bromine, which causes the failure of the semiconductor device. However, the high temperature reliability was lowered, which was a problem.

In order to solve the above problems, a method has been proposed in which a metal hydroxide that is non-halogen-nonantimony is added as an inorganic flame retardant. However, when the metal hydroxide is used, there is a problem that the mold releasability is inferior, and therefore, a mold release agent obtained by improving this has been studied. For example, it has been proposed to use at least one of a high acid value polyethylene wax and a long-chain alkyl phosphate ester compound (see Patent Document 1).
JP 2000-53875 A

  However, when a release agent having a high acid value as described above is used, there arises a new problem that the resin viscosity becomes high. In addition, when the surface of the metal hydroxide is treated with a release agent in advance, the adhesion between the metal hydroxide and the resin component is reduced, resulting in problems such as reduced moisture resistance reliability and mechanical strength. .

  The present invention has been made in view of the above circumstances, and has a resin composition for encapsulating a semiconductor which is excellent in moisture resistance reliability, flame retardancy and moldability as well as safety, as well as in mold release properties. An object of the present invention is to provide a semiconductor device using this.

In order to achieve the above object, the present invention provides a resin composition for semiconductor encapsulation containing the following components (A) to (E), wherein the content of the following component (B) is the entire resin composition. Resin for semiconductor encapsulation which is set in the range of 5 to 30% by weight and the total content of the following components (B) and (C) is set in the range of 60 to 90% by weight of the entire resin composition The composition is the first gist.
(A) Thermosetting resin.
(B) A metal compound that releases water or carbon dioxide in the range of 200 to 400 ° C.
(C) An inorganic filler other than the metal compound as the component (B).
(D) A release agent having an acid value of 1 or more and less than 10.
(E) A mold release agent having an acid value of 10 or more and 20 or less and an average number of acidic groups in one molecule of 0.1 to 0.3.

  And this invention makes the 2nd summary the semiconductor device formed by resin-sealing a semiconductor element using the said resin composition for semiconductor sealing.

  That is, the present inventors have intensively studied in order to obtain a resin composition for sealing having excellent flame retardancy and excellent mold releasability and moldability. As a result, as a flame retardant imparting flame retardancy, a metal compound that releases water or carbon dioxide [component (B)] in the range of 200 to 400 ° C. is used, and the two types of release agents [( When the component (D) and the component (E) are used in combination, and the content of the specific metal compound is set in a specific range, it is possible to prevent a decrease in releasability from the mold and to suppress an increase in viscosity. It has become possible to achieve the present invention by finding that the intended purpose is achieved.

  Thus, the present invention includes a thermosetting resin [component (A)], a metal compound that releases water or carbon dioxide in the range of 200 to 400 ° C. [component (B)], and components other than the component (B). Inorganic filler [component (C)] and two specific types of release agents [component (D) and component (E)], and the content of the metal compound [component (B)] and this It is the resin composition for semiconductor sealing which makes the total content of a metal compound and an inorganic filler the specific range, respectively. For this reason, it is excellent in the fluidity | liquidity and mold release property at the time of shaping | molding with a flame retardance, and was equipped with favorable moldability. Therefore, a highly reliable semiconductor device can be obtained.

  And when the content of the two specific types of release agents [component (D) and component (E)] is in a specific range, excellent moisture resistance reliability can be obtained together with good releasability. .

  The resin composition for semiconductor encapsulation of the present invention comprises a thermosetting resin (A component), a specific metal compound (B component), an inorganic filler (C component), and two specific types of release agents ( D component, E component) and is usually in the form of a powder or a tablet obtained by tableting this. Alternatively, after the resin composition is melt-kneaded, it is a sheet-shaped sealing material that is formed into a granular shape that is formed into a substantially cylindrical shape, and further into a sheet shape.

  Examples of the thermosetting resin (component A) include epoxy resins, polymaleimide resins, unsaturated polyester resins, phenol resins, and the like, and those containing a curing agent for these thermosetting resins as necessary. In particular, in the semiconductor encapsulation field of the present invention, it is preferable to use an epoxy resin or a polymaleimide resin.

  As said epoxy resin, it does not specifically limit and a conventionally well-known thing is used. For example, bisphenol A type, phenol novolac type, cresol novolac type, biphenyl type and the like can be mentioned. These may be used alone or in combination of two or more.

And among the said epoxy resins, as a biphenyl type epoxy resin, it is represented by following General formula (1). That is, it is a glycidyl ether of 3,3 ′, 5,5′-tetraalkyl-4,4′-biphenol, and particularly from the viewpoint of low hygroscopicity and reactivity, R _{1 to} R ₄ in the formula (1). It is particularly preferable to use a biphenyl type epoxy resin in which all are methyl groups.

  In addition, the polymaleimide resin is not particularly limited, and a conventionally known one is used and has two or more maleimide groups in one molecule. For example, N, N′-4,4′-diphenylmethane bismaleimide, 2,2-bis- [4- (4-maleimidophenoxy) phenyl] propane and the like can be mentioned.

  If necessary, a curing agent is used for the thermosetting resin (component A). For example, conventionally known materials such as phenol resins, acid anhydrides, and amine compounds are used.

  Examples of the phenol resin include phenol novolak, cresol novolak, bisphenol A type novolak, naphthol novolak, and phenol aralkyl resin.

  When a biphenyl type epoxy resin is used as the epoxy resin, a phenol aralkyl resin is preferably used as the curing agent. Further, the combination of the o-cresol novolac type epoxy resin and the phenol novolac resin is excellent in terms of balance of characteristics.

  On the other hand, the curing agent when using a polymaleimide resin as the thermosetting resin (component A) is not particularly limited, and conventionally known ones are used. Examples thereof include alkenylphenols and amines obtained by reacting the curing agent for epoxy resins with an allyl halide in the presence of an alkali.

  And when the main component of a thermosetting resin (A component) is an epoxy resin, and the hardening agent used together is a phenol resin, both content ratio is a phenol resin per 1 equivalent of epoxy groups in the said epoxy resin. It is preferable to set it so that the hydroxyl group in it is 0.7 to 1.3 equivalent, and it is particularly preferable to set it to be 0.9 to 1.1 equivalent.

  The specific metal compound (component B) used together with the thermosetting resin (component A) releases water or carbon dioxide in the range of 200 to 400 ° C., for example, metal hydroxide, metal water There are oxide salts, layered bimetallic hydroxides such as hydrotalcite. Examples of such metal hydroxides include aluminum hydroxide and magnesium hydroxide. Examples of the metal hydroxide salt include trinickel tetranitrate tetrahydroxide and tricobalt dinitrate tetrahydroxide. Further, as the hydrotalcite-like compound, those using magnesium and aluminum, magnesium and iron, nickel and aluminum or iron, cobalt and aluminum, and carbonic acid combined with zinc and aluminum as anions are known. Such a hydrotalcite compound is represented by the following general formula (2).

That is, the hydrotalcite compound represented by the above formula (2) has a layered structure like brucite Mg (OH) ₂ and the layer has a positive charge when a trivalent metal cation enters. In order to neutralize the structure, an anion and water are intercalated between the layers. Examples of the anion in the above formula (2) include carbonate ions.

  A semiconductor device sealed with this resin composition may be soldered at 260 ° C., but a semiconductor device having a decomposition start temperature (dehydration start temperature) of 200 ° C. or higher can also be used. Preferably, it has a decomposition start temperature of 240 ° C. or higher. Specific examples of the compound include aluminum hydroxide, dawsonite, calcium aluminate having a dehydration start temperature of about 250 ° C., zinc borate and magnesium hydroxide having a dehydration start temperature of about 320 ° C. In addition to this, it is naturally possible to use one having a decomposition start temperature of 200 to 400 ° C.

  It is also possible to use a combination of the above aluminum hydroxide and magnesium hydroxide. In this case, the ratio of aluminum hydroxide to magnesium hydroxide is preferably set in the range of aluminum hydroxide: magnesium hydroxide = 1: 9 to 9: 1, particularly preferably 6: 4 to 8: on a weight basis. 2. The above-mentioned aluminum hydroxide prevents temperature rise due to endothermic effect and is excellent in flame resistance for a short time, but when used in combination with magnesium hydroxide, the effect of magnesium hydroxide that decomposes at a temperature close to the combustion temperature of the resin composition In addition to obtaining flame resistance, it is possible to prevent foaming of the resin composition due to dehydration at a low temperature, which is likely to occur when the aluminum hydroxide is used.

  The decomposition start temperature (dehydration start temperature) of a metal compound that releases water or carbon dioxide at 200 to 400 ° C., that is, has a decomposition start temperature (dehydration start temperature) within the above temperature range, is as follows. It is measured as follows. That is, using a differential scanning calorimeter (manufactured by Perkin Elmer Co.), the starting temperature of weight reduction is measured at a heating rate of 10 ° C./min. If the starting temperature is unclear due to a gentle weight reduction, a tangent line is drawn from the maximum slope of the first stage weight reduction and the intersection with the weight of 100% is taken as the decomposition starting temperature.

  Furthermore, as the specific metal compound (component B), a composite metal hydroxide can be used. For example, a compound represented by the following general formula (3) is obtained. The complex metal hydroxide usually has a decomposition start temperature (dehydration start temperature) in the range of 200 to 400 ° C.

  Regarding the composite metal hydroxide represented by the general formula (3), M indicating the metal element in the formula (3) is a non-transition metal element such as Al, Mg, Ca, Sn, Zn, Ni, Examples thereof include transition metal elements such as Co, Cu, Fe, and Ti.

  Moreover, Q which shows the metal element in the composite metal hydroxide represented by the general formula (3) is a transition metal element other than M, which is other than scandium, yttrium, lanthanide series, and actinide series. For example, iron, cobalt, nickel, palladium, copper, zinc and the like can be mentioned, and these are selected singly or in combination of two or more.

  The composite metal hydroxide is preferably not nearly flaky but as nearly spherical as possible. By having such a shape, an increase in the viscosity of the resin composition is suppressed, and a low viscosity and good moldability can be obtained.

  Such a specific metal compound (component B) preferably has an average particle size in the range of 0.1 to 70 μm, particularly preferably 0.5 to 50 μm. The maximum particle size is preferably in the range of 75 to 150 μm, and particularly preferably 75 to 100 μm. The average particle diameter and the maximum particle diameter can be measured using, for example, a laser diffraction / scattering particle size distribution measuring apparatus.

  Thus, it is essential to use a specific metal compound (component B) that releases water or carbon dioxide in the range of 200 to 400 ° C., that is, has a decomposition start temperature in the range of 200 to 400 ° C. However, calcium hydroxide having a decomposition start temperature at 450 ° C., kaolin clay having a decomposition start temperature at 500 ° C., and the like can be used in combination as long as the effects are not impaired.

  Content of the said specific metal compound (B component) needs to be set to the range of 5 to 30 weight% of the whole resin composition. Particularly preferred is 5 to 20% by weight. That is, if it is less than 5% by weight, the flame retardancy is lowered. Further, if it exceeds 30% by weight, foaming due to dehydration and decarboxylation tends to occur.

  And as inorganic fillers (C component) other than the said B component used with the said A component and B component, it does not specifically limit and conventionally well-known various fillers are mention | raise | lifted. Examples thereof include quartz glass powder, talc, silica powder, alumina powder, calcium carbonate, boron nitride, silicon nitride, and carbon black. These may be used alone or in combination of two or more. And as said inorganic filler (C component), it is preferable to use a silica powder from the point that the linear expansion coefficient of the hardened | cured material obtained can be reduced. Especially, it is especially preferable from the point of the favorable fluidity | liquidity of a resin composition to use a fused silica powder, especially a spherical fused silica powder as a silica powder. Moreover, in the said inorganic filler (C component), it is preferable that the average particle diameter is the range of 10-70 micrometers, More preferably, it is 10-50 micrometers. The average particle diameter can be measured using, for example, a laser diffraction / scattering particle size distribution measuring apparatus.

  And the total amount of the said specific metal compound (B component) and an inorganic filler (C component) needs to set to the range of 60 to 90 weight% of the whole resin composition. Particularly preferred is 70 to 90% by weight. That is, if the total amount of both is less than 60% by weight, the flame retardancy is lowered, and if it exceeds 90% by weight, the viscosity of the resin composition is increased and the moldability is lowered.

  The specific two types of release agents (D component and E component) used together with the above-mentioned AC components are a release agent (D component) having an acid value of 1 or more and less than 10, and an acid value of 10 or more and 20 or less. Thus, the release agent (E component) has an average acidic group number in the range of 0.1 to 0.3.

  The release agent (D component) having an acid value of 1 or more and less than 10 has a long chain alkyl group and a polar group. For example, a long chain fatty acid ester, a long chain fatty acid ester amide, an organic acid long chain alkyl ester Organic acid long-chain alkylamides, metal salts of long-chain alkylcarboxylic acids, polyalkylene glycol esters, and the like. In the case of natural wax, it is a mixture of a plurality of compounds as long as it has a low free acid content and falls within the above acid value. Such a release agent with a low acid value has a small interaction with the metal compound (component B) that acts as a flame retardant, and not only lowers the viscosity of the resin composition but also improves the release properties of the entire composition. Let Further, those having a small number of polar groups in the molecule are preferable, and those having an ester group having a saponification value of 95 or less are preferable because of high release effect. However, if the acid value is less than 1, the compatibility with the resin component is lowered, the dispersion of the release agent is liable to occur, and the release property becomes unstable.

  Specific examples of the release agent (D component) having a low acid value include natural waxes such as carnauba wax, aliphatic alcohol esters of palmitic acid, dialiphatic alcohol esters of o-phthalic acid, and the like. It is done. Among these, carnauba wax is particularly preferable because of its long history of use. The carnauba wax is a hard natural wax and is obtained from carnauba pine leaves of Brazil. And a linear aliphatic with lactic acid etc. which are hydroxy carboxylic acid which has a C20-C30 long-chain linear aliphatic carboxylic acid and a C30-C34 linear aliphatic alcohol ester as a main component. Alcohol esters and linear aliphatic alcohol esters of p-hydroxycinnamic acid and p-methoxycinnamic acid which are aromatic alkenyl carboxylic acids are included. In addition, free acids, aliphatic alcohols, hydrocarbons, etc. include. On average, it is a wax mainly composed of an ester having about 50 carbon atoms, and the average molecular weight corresponds to 700 to 800. Since it contains a polar group, it is well-familiar with the resin, and hydroxycinnamic acid has an antioxidant effect and also has heat resistance.

  Next, as a release agent (component E) having an acid value of 10 or more and 20 or less and an average number of acidic groups in one molecule of 0.1 to 0.3, esters of long-chain alkyl fatty acids, long And metal salts of chain alkyl fatty acids. These release agents interact with a thermally decomposable inorganic substance such as a metal compound (component B) to be dispersed and stabilized. If there is agglomeration of a flame retardant such as a metal compound (component B), there is a possibility that resin cracking will occur using the agglomerated part as a nucleus, or resin adhesion to the mold may be caused. This is effective as a countermeasure. Examples of the acidic group include carboxylic acid, sulfonic acid, phenolic hydroxyl group and the like, and the average number of acidic groups must be 0.1 to 0.3 per molecule. That is, when the number is less than 0.1, the dispersibility of the metal compound (component B) cannot be obtained, and when the number exceeds 0.3, the viscosity increases due to interaction with the metal compound (component B). is there. As the acidic group, carboxylic acid is preferable from the viewpoint of availability. Furthermore, as said mold release agent (E component), an acid value must be the range of 10-20. That is, when the acid value exceeds 20, the viscosity of the entire composition is increased due to the interaction with the thermosetting resin (component A), and the fluidity and moldability are deteriorated. Such an average acidic group number is measured as follows. That is, the acid value of the release agent (component E) is determined by titration with a potassium hydroxide solution, and the number of moles of carboxylic acid (acidic group) per weight is calculated. Next, the average number of acidic groups per molecule of the release agent is calculated by multiplying the weight average molecular weight of the release agent (component E). The weight average molecular weight is measured in terms of standard polystyrene by gel permeation chromatography (GPC).

  Most of the polyethylene oxide wax that is generally used falls within the range of an acid value of 10 to 30, but most of them have an average acidic group number of 0.4 or more per molecule, and the viscosity of the resin composition is reduced. There is a problem of increasing. And as an average molecular weight of the said mold release agent (E component), the thing of 800-1500 is preferable.

  Specific examples of the release agent (component E) include stearic acid ester wax, calcium stearate, montanic acid ester wax, and partially saponified products of montanic acid ester wax. The above-mentioned montanic acid is a mineral wax that an ancient plant has altered in the ground, and has as its main component an ester of a carboxylic acid having about 34 carbon atoms. Industrially, a montanic acid ester wax obtained by reacting montanic acid with ethylene glycol or the like, and a mixture of this with saponified with calcium or the like are commercially available.

The above-mentioned montanic acid is represented by C ₂₇ H ₅₅ COOH, but the raw material of the mineral wax montanic acid wax is made by solvent extraction of lignite, and its composition is a long chain ester, free higher fatty acid or alcohol, Resin quality. This is purified with chromic acid or the like to obtain a carboxylic acid, and various waxes are produced by esterification or saponification. The purified product is a linear carboxylic acid having 28 to 30 carbon atoms, which is commercially available by esterification with ethylene glycol, butylene glycol or the like or saponification with calcium hydroxide.

  Since the above-mentioned montanic acid ester has an appropriate acid value, it is adsorbed on a flame retardant having a high basicity such as a metal hydroxide among metal compounds (component B) and the like such as a metal hydroxide. Improve dispersion stability. However, the adhesion between the resin component and the flame retardant is ensured, and the flame retardant becomes difficult to adhere to the mold. In addition, calcium in the saponified wax is considered to be a neutralizing agent for the acidic compound and added to the oxide film generated on the mold surface or the like to have a repairing effect that prevents a reduction in the releasing effect. Therefore, it is particularly preferable to use a montanic acid ester-based wax, a montanic acid saponified wax, and a carnauba wax because the mold release effect can be continuously obtained.

  A particularly preferred combination of the D and E components that are the above specific release agents includes those using three components of carnauba wax, a montanic acid ester wax, and a partially saponified product of montanic acid ester. It is particularly preferable to use the partially saponified (about 25%) product of the above-mentioned montanic acid ester in an amount of 50% by weight or more of the entire mold release agent and 10 to 40% by weight of carnauba wax and montanic acid ester wax, respectively. This corresponds to 12.5 to 20% by weight of a saponified product of montanic acid ester, 10 to 40% by weight of carnauba wax, and 70 to 77.5% by weight of montanic acid ester wax.

  The interaction between the flame retardant metal compound (component B) and the mold release agent D and component E is a flame retardant metal compound (component B and component B). Can be evaluated by measuring the viscosity over time. For example, 100 parts by weight of a metal compound (component B) which is a flame retardant is added to 100 parts by weight (hereinafter referred to as “parts”) of a release agent (components D and E) and heated on a hot plate at 175 ° C. Mix and place between rotational viscometer plates and continue to rotate at 175 ° C. to plot the change in viscosity. A wax having a high acid value and a strong interaction with the metal compound (B component) has a high viscosity of the mixture with the metal compound (B component) which is a flame retardant, and has a lot of acidic groups in the molecule. The viscosity increases over time.

  That is, carnauba wax (saponification number 80) with a low ester group content in the molecule has a lower viscosity than montanic acid ester wax (saponification number 140), and it seems that exudation to the mold surface is easy. Effective for mold release. However, when used alone, it is also applied to the surface of a flame retardant such as a metal compound (component B), so that the flame retardant close to the mold surface is taken out from the resin composition and adheres to the mold surface. As a contact point is formed, it may be difficult to separate from the mold if it is continuously formed.

  And, the above-mentioned montanic acid ester improves the dispersion stability, and the partial saponified product of montanic acid ester is effective for mold scratches, oxide neutralization, etc., so that these combinations produce the best results. Become.

  The content ratio of the D component and the E component, which are the above specific release agents, is preferably set in the range of 0.1 to 1.0% by weight of the entire resin composition for semiconductor encapsulation, and is particularly preferably set to a value of 0.00. 3 to 0.45% by weight. That is, if the content of the release agent component (D component, E component) is too small, such as less than 0.1% by weight, it is difficult to obtain sufficient mold releasability. This is because when the content exceeds 20% by weight, good releasability is exhibited, but the adhesive strength to the lead frame and the semiconductor element is impaired, and the moisture resistance reliability tends to be inferior.

  In addition to the above components A to E, a curing accelerator, a pigment, a surface treatment agent, a flexibility imparting agent, and the like are appropriately added to the resin composition for encapsulating a semiconductor according to the present invention as necessary. Can do.

  Examples of the curing accelerator include conventionally known ones such as 1,8-diazabicyclo (5,4,0) undecene-7, tertiary amines such as triethylenediamine, imidazoles such as 2-methylimidazole, and triphenyl. Examples thereof include phosphorus curing accelerators such as phosphine, tetraphenylphosphonium, and tetraphenylborate. These can be used alone or in combination of two or more. And it is preferable to set the mixture ratio of the said hardening accelerator to the ratio of 0.1 to 2.0 weight% of the whole resin composition for semiconductor sealing.

  Examples of the pigment include carbon black and titanium oxide.

  Furthermore, examples of the surface treatment agent include a coupling agent such as a silane coupling agent, and examples of the flexibility imparting agent include silicone resin and butadiene-acrylonitrile rubber.

  In the resin composition for encapsulating a semiconductor according to the present invention, when an organic flame retardant or a red phosphorus flame retardant is used in addition to the above components, the amount of the metal compound (component B) used is reduced. It is preferable in terms of moisture resistance reliability.

  Examples of the organic flame retardant include nitrogen-containing organic compounds, phosphorus-containing organic compounds, and phosphazene-based compounds, and nitrogen-containing organic compounds are particularly preferably used.

  Examples of the nitrogen-containing organic compound include compounds having a heterocyclic skeleton such as melamine derivatives, cyanurate derivatives, and isocyanurate derivatives.

  These organic flame retardants are used alone or in combination of two or more. And it is preferable to set content of the said organic flame retardant in the range of 1-10 weight% of the whole usage-amount of the said specific metal compound (B component), Most preferably, it is 1-5 weight%. .

  The organic flame retardant may be blended after mechanically mixing with the specific metal compound (component B), which is the decomposable flame retardant, in advance, or the organic flame retardant is dissolved in a solvent. A material obtained by adding a specific metal compound (component B) to remove the solvent and performing surface treatment may be used.

  On the other hand, examples of the red phosphorus flame retardant include red phosphorus powder or red phosphorus powder whose surface is protected with various organic and inorganic substances.

  And it is preferable to set content of the said red phosphorus flame retardant to the range of 1 to 10 weight% of the whole usage-amount of the said specific metal compound (B component) similarly to the case of the said organic flame retardant. Particularly preferably, it is 1 to 5% by weight.

  And in the resin composition for semiconductor encapsulation concerning this invention, the suitable combination of each component containing the said AE component is as follows. That is, the thermosetting resin (component A) is preferably an epoxy resin, especially a biphenyl type epoxy resin from the viewpoint of good fluidity, and the curing agent used in combination with the thermosetting resin includes From the viewpoint of fluidity, a phenol aralkyl resin or the like is preferable. Moreover, although the fluidity is somewhat inferior, the combination of the cresol novolac type epoxy resin and the phenol novolac resin is also excellent in the property balance.

  Furthermore, as the metal compound (component B) that releases water or carbon dioxide within the range of 200 to 400 ° C., aluminum hydroxide and magnesium hydroxide are preferable, and the combined use thereof is more preferable. And as said inorganic filler (C component), it is preferable to use spherical fused silica powder. And as a said D component among specific release agents, carnauba wax is preferable. Further, as the E component, there may be two or more acidic groups in the molecule such as polyethylene oxide, and it is not preferable to cause significant thickening during heating and mixing with the metal compound (B component). It is preferable to use monobasic acid esters and salts. In particular, a montanic acid ester and a saponified product thereof are preferable from the viewpoint of dispersibility of the metal compound (component B). In the E component, the combined use of an ester and a salt is particularly effective in releasability during molding.

  The resin composition for semiconductor encapsulation according to the present invention can be produced, for example, as follows. That is, a thermosetting resin containing a curing agent (A component), a specific metal compound (B component), an inorganic filler (C component) and two specific release agents (D component, E component) and necessary Depending on the case, other additives are blended at a predetermined ratio and mixed. Next, this mixture is melt-kneaded in a heated state of about 60 to 150 ° C. using a kneader such as a mixing roll machine, and cooled to room temperature. And the target resin composition for semiconductor sealing can be manufactured according to a series of processes of grind | pulverizing by a well-known means, and tableting as needed.

  Alternatively, the semiconductor encapsulating resin composition is put into a kneader and kneaded in a molten state, and then continuously molded into a substantially cylindrical granule by a series of steps. A stopping resin composition can be produced.

  Further, the mixture of the resin composition for semiconductor encapsulation is received on a pallet, and after cooling, the sheet-like composition is formed by a method such as press rolling, roll rolling, or coating with a solvent mixture to form a sheet. A resin composition for semiconductor encapsulation can be produced.

  The method for sealing a semiconductor element using the thus obtained semiconductor sealing resin composition (powder, tablet, granule, etc.) is not particularly limited, and is known as usual transfer molding or the like. The molding method can be used.

  Moreover, a semiconductor device by flip-chip mounting can be manufactured using the sheet-shaped resin composition for encapsulating a semiconductor, for example, as follows. That is, the resin composition for sealing a sheet-like semiconductor is disposed on the electrode surface side of a semiconductor element provided with bonding bumps or on the bump bonding part side of a circuit board, and the semiconductor element and the circuit board are bump bonded. In addition, the semiconductor device can be manufactured by flip-chip mounting by performing adhesive sealing by resin sealing.

  Next, examples will be described together with comparative examples.

  First, each component shown below was prepared.

[Epoxy resin a]
Cresol novolac type epoxy resin (epoxy equivalent 195, softening point 65 ° C.)

[Epoxy resin b]
Biphenyl type epoxy resin [in the above formula (1), R _{1 to} R ₄ are all methyl groups, epoxy equivalent 193, melting point 105 ° C.]

[Phenolic resin a]
Phenol novolac resin (hydroxyl equivalent 105, softening point 83 ° C)

[Phenolic resin b]
Phenol aralkyl resin (hydroxyl equivalent 172, softening point 70 ° C)

[Decomposable inorganic compound a]
Zinc hydroxide (average particle size 1 μm, maximum particle size 15 μm, decomposition start temperature 125 ° C.)

[Decomposable inorganic compound b]
Aluminum hydroxide (average particle size 13 μm, maximum particle size 60 μm, decomposition start temperature 250 ° C.)

[Decomposable inorganic compound c]
Magnesium hydroxide (average particle size 0.8 μm, maximum particle size 10 μm, BET specific surface area 7 m ² / g, decomposition start temperature 350 ° C.)

[Decomposable inorganic compound d]
Magnesium / aluminum-based hydrotalcite [Mg _0.68 Al _0.32 (OH) ₂ (CO ₃ ) _0.16 · 0.5H ₂ O, average particle size 0.4 μm, decomposition start temperature 280 ° C./430° C.

[Decomposable inorganic compound e]
Magnesium / zinc composite metal hydroxide [0.8 (MgO) /0.2 (ZnO) / H ₂ O, average particle diameter 1.0 μm, BET specific surface area 3 m ² / g, decomposition start temperature 285 ° C.

[Decomposable inorganic compound f]
Magnesium carbonate (average particle size 12 μm, BET specific surface area 34 m ² / g, decomposition start temperature 600 ° C.)

[Inorganic filler]
Spherical fused silica powder with an average particle size of 30 μm

[Curing accelerator]
1,8-diazabicyclo (5,4,0) undecene-7

[Wax a]
Polyethylene wax (acid number 0, average molecular weight 1300)

[Wax d1]
Palmitic acid ester of aliphatic alcohol having 40 carbon atoms (acid value 1.2, average molecular weight 817, average number of acidic groups 0.02 in one molecule)

[Wax d2]
Carnauba wax (acid number 6, average molecular weight 750, average number of acidic groups 0.08 per molecule)

[Wax d3]
Ethylene bis-stearic acid amide (acid number 9, molecular weight 531, average number of acidic groups in one molecule 0.1)

[Wax e1]
Partially saponified (25%) montanic acid ester wax (melting point 101 ° C., acid number 13, average molecular weight 875, saponification number 112, average number of acidic groups 0.28 per molecule)

[Wax e2]
Montanic acid ethylene glycol ester (melting point 82 ° C., acid value 18, average molecular weight about 870, saponification value 153, average number of acidic groups 0.28 in one molecule)

[Wax b]
Oxidized branched polyethylene wax (melting point 106 ° C., acid value 17, average molecular weight about 1300, average number of acidic groups 0.39 per molecule)

[Wax c]
Oxidized linear polyethylene wax (melting point 110 ° C., acid value 60, average molecular weight about 750, average number of acidic groups 0.7 in one molecule)

〔Carbon black〕

〔Silane coupling agent〕
γ-glycidoxypropyltrimethoxysilane

[Stress relaxation agent]
Methyl methacrylate-butadiene-styrene copolymer powder (average particle size 0.2 μm)

[Examples 1-9, Comparative Examples 1-8]
Each component shown in Tables 1 and 2 below is blended in the proportions shown in the same table, melt-kneaded for 3 minutes with a mixing roll machine (temperature 100 ° C.), then cooled and solidified, and then pulverized to form powder. An epoxy resin composition for semiconductor encapsulation was obtained.

  Using the powdery epoxy resin compositions of Examples and Comparative Examples thus obtained, flame retardancy, flow tester viscosity and continuous moldability were measured and evaluated. These results are shown in Tables 3 to 4 below.

〔Flame retardance〕
A test piece having a thickness of 1/16 inch was molded using each epoxy resin composition, and the flame retardancy was evaluated according to the method of UL94 V-0 standard. In addition, a pass means a 94-V0 pass.

[Flow tester viscosity]
2 g of each epoxy resin composition was precisely weighed and tableted into tablets. And this was put into the pot of the Koka type flow tester, and it measured by applying a load of 10 kg. The melt viscosity of the sample was determined from the moving speed of the piston when the molten epoxy resin composition was extruded through a hole in the die (diameter: 1.0 mm × 10 mm).

[Continuous formability]
Next, using each of the epoxy resin compositions described above, tablet-shaped epoxy resin compositions were prepared by tableting. Using a semiconductor package automatic molding machine (manufactured by TOWA, multi-plunger mold UPS-40L), an attempt was made to continuously perform 1000 shots in a 28-pin small outline package (SOP-28) molding die. In this continuous molding, the mold releasability of the package was evaluated, and the number of molding shots where a problem occurred in the releasability was confirmed.

  As a result of the above table, the example products had excellent flame retardancy, the flow tester viscosity was not high, and good results were obtained with respect to continuous moldability. On the other hand, one comparative example product containing no specific metal compound, five comparative example products using an inorganic compound having a low decomposition start temperature, and six comparative example products using an inorganic compound having a high decomposition start temperature are flame retardant. It turns out that it is inferior. In addition, Comparative Example 2 using a polyethylene wax having an acid value of 0 is inferior in continuous moldability, and Comparative Example 3 using an oxidized polyethylene wax having a high number of acidic groups has high flow tester viscosity and inferior continuous moldability. Met. And the comparative example 4 products with much content of a specific metal compound had a high flow tester viscosity, and were inferior to continuous moldability. Further, Comparative Example 7 with a low content of a specific metal compound is inferior in flame retardancy, and Comparative Example 8 with a low total amount of the specific metal compound and inorganic filler is inferior in flame retardancy. The hardness immediately after molding was low, and the peelability from the molding die was poor.

Claims (6)

A semiconductor sealing resin composition containing the following components (A) to (E), wherein the content of the following component (B) is set in the range of 5 to 30% by weight of the entire resin composition, and A resin composition for encapsulating a semiconductor, wherein the total content of the following component (B) and component (C) is set in a range of 60 to 90% by weight of the entire resin composition.
(A) Thermosetting resin.
(B) A metal compound that releases water or carbon dioxide in the range of 200 to 400 ° C.
(C) An inorganic filler other than the metal compound as the component (B).
(D) A release agent having an acid value of 1 or more and less than 10.
(E) A mold release agent having an acid value of 10 or more and 20 or less and an average number of acidic groups in one molecule of 0.1 to 0.3.   The resin composition for semiconductor encapsulation according to claim 1, wherein the release agent as the component (E) is one or more release agents selected from at least one of fatty acid esters and fatty acid metal salts.   2. The resin composition for semiconductor encapsulation according to claim 1, wherein the release agent as the component (E) is a mixed release agent comprising a fatty acid ester and a fatty acid metal salt.   The resin composition for semiconductor encapsulation according to claim 2 or 3, wherein the fatty acid is montanic acid.   The total content of the component (D) and the component (E) is set in a range of 0.1 to 1.0% by weight of the entire resin composition. A semiconductor sealing resin composition.   The semiconductor device formed by resin-sealing a semiconductor element using the resin composition for semiconductor sealing as described in any one of Claims 1-5.