JP6389382B2 - Semiconductor encapsulating resin sheet and resin encapsulating semiconductor device - Google Patents

Description

  The present invention relates to a semiconductor sealing resin sheet and a resin sealing semiconductor device using the same.

As an electronic component used for an electronic device, there is a semiconductor package obtained by resin-sealing a semiconductor element. Conventionally, this semiconductor package is generally manufactured by transfer molding of a solid epoxy resin sealing material. On the other hand, with recent downsizing and weight reduction of electronic devices, high-density mounting of electronic components on a wiring board has been required, and semiconductor packages are also being reduced in size, thickness, and weight. .
Specifically, semiconductor packages such as LOC (Lead on Chip), QFP (Quad Flat Package), smaller and lighter CSP (Chip Size Package), and BGA (Ball Grid Array) have been developed. More recently, flip-chips of a so-called face-down type package, a wafer level CSP, and the like have been developed in which the circuit surface of a semiconductor element is mounted facing the wiring board side.

  As described above, with the progress of thinning of the semiconductor package and the like, there are cases where conventional transfer molding cannot cope. That is, for example, when the semiconductor package is thinned, the proportion of the inorganic filler compounded in consideration of the characteristics after curing, etc. in the sealing material increases, so the melt viscosity of the sealing material during transfer molding is high. As a result, the filling property is lowered. As a result, defective filling, residual voids in the molded product, wire flow (bonding wire deformation / damage), increased stage shift, and the like occur, and the quality of the molded product decreases.

  Therefore, application of a compression (compression) molding method has been studied as a sealing method instead of transfer molding, and various sheet-like sealing materials used for this have been proposed. For example, Patent Document 1 discloses a sealing resin sheet obtained by laminating a plurality of resin sheets made of an epoxy resin composition containing an epoxy resin, a curing agent, a curing catalyst (or a curing accelerator), and an inorganic filler, and thermocompression bonding. It is disclosed. Patent Document 2 discloses a sheet-like sealing material having a thickness of 3.0 mm or less made of a thermosetting resin composition that is softened or melted at 70 to 150 ° C.

  However, the former resin sheet for sealing has a problem that warpage occurs in the molded product when the package or wafer size is increased (this problem is caused by adding a large amount of an inorganic filler such as silica, for example). However, in this case, the increase in melt viscosity causes problems such as poor filling as described above). On the other hand, although the latter can sufficiently cope with a large-sized package or the like, if the sheet thickness is reduced to about 0.5 mm in order to reduce the thickness, it becomes easy to break and it is difficult to carry it into the mold. There was a problem in terms of handling.

Japanese Patent Laid-Open No. 8-73621 JP 2006-216899 A

  The present invention has been made to solve the above-described problems of the prior art, and even when the thickness is reduced, the handleability and formability are good, and the flexibility is maintained over a long period of time. Resin sheet for semiconductor encapsulation capable of efficiently and satisfactorily sealing semiconductor elements by a compression molding method, and high quality and highly reliable resin sealed using such a resin sheet for semiconductor encapsulation An object of the present invention is to provide a sealed semiconductor device.

  As a result of intensive studies to achieve the above object, the present inventors have used a specific dispersant in combination with a crystalline epoxy resin, and thus handleability and moldability are good even when the thickness is reduced. In addition, the inventors have found that a resin sheet for semiconductor encapsulation that retains flexibility over a long period of time can be obtained, and the present invention has been completed.

That is, the resin sheet for encapsulating a semiconductor according to one embodiment of the present invention includes (A) an epoxy resin containing a crystalline epoxy resin, (B) a phenol resin curing agent, (C) a curing accelerator, and (D) an inorganic filler. And (E) an epoxy resin composition comprising a polymeric cationic dispersant as an essential component, wherein the polymeric cationic dispersant is a polymer comprising a hydrocarbon-based graft copolymer having a polyamine as a main chain. It is characterized by being formed into a sheet of an epoxy resin composition which is a cationic dispersant .

  A resin-encapsulated semiconductor device according to another aspect of the present invention is characterized in that a semiconductor element is encapsulated by compression molding using the above-described resin sheet for encapsulating a semiconductor.

  According to the present invention, the handling and moldability are good and the flexibility is maintained over a long period of time. By using this, the semiconductor element can be efficiently and satisfactorily sealed by the compression molding method. A resin sheet and a resin-encapsulated semiconductor device having such a high-quality and high reliability that is sealed with such a semiconductor-encapsulating resin sheet can be obtained.

  Embodiments of the present invention will be described below.

First, each component of the epoxy resin composition used in the present invention will be described.
The epoxy resin of component (A) used in the present invention includes a crystalline epoxy resin. The crystalline epoxy resin can be used as long as it is an epoxy resin having crystallinity without being limited by the molecular structure, molecular weight, etc. Among them, a biphenyl type epoxy resin having crystallinity at normal temperature is preferable. The biphenyl type epoxy resin is an epoxy resin having a biphenyl skeleton, but the biphenyl skeleton in the present invention includes those obtained by hydrogenating at least one aromatic ring among the biphenyl rings.
Specific examples of the biphenyl type epoxy resin include, for example, 4,4′-bis (2,3-epoxypropoxy) biphenyl, 4,4′-bis (2,3-epoxypropoxy) -3,3 ′, 5, Epoxy obtained by reacting 5′-tetramethylbiphenyl, epichlorohydrin and a biphenol compound such as 4,4′-biphenol or 4,4 ′-(3,3 ′, 5,5′-tetramethyl) biphenol Examples thereof include resins. Among these, 4,4′-bis (2,3-epoxypropoxy) -3,3 ′, 5,5′-tetramethylbiphenyl, 4,4 ′-(3,3 ′, 5,5′- Tetramethyl) biphenyl glycidyl ether is preferred. A biphenyl type epoxy resin may be used individually by 1 type, and 2 or more types may be mixed and used for it.

  Examples of commercially available products used as the biphenyl type epoxy resin include, for example, YX-4000 (epoxy equivalent 185, melting point 105 ° C.), YX-4000K (epoxy equivalent 185, melting point 105 ° C.) manufactured by Mitsubishi Chemical Corporation, YX-4000H (epoxy equivalent 193, melting point 105 ° C.), YL-6121H (epoxy equivalent 172, melting point 105 ° C.) (all are trade names), and the like.

  By using a crystalline epoxy resin, particularly a biphenyl type epoxy resin, it is possible to easily maintain the melt viscosity of the composition within a suitable range even if the inorganic filler of the component (D) described later is highly filled, and further heat resistance. The resin sheet for semiconductor sealing excellent in property can be obtained.

  In the present invention, one or more epoxy resins other than the biphenyl epoxy resin can be blended within a range that does not impair the effects of the present invention regardless of crystallinity and non-crystallinity. Examples of epoxy resins other than biphenyl type epoxy resins include cresol novolac type epoxy resins, phenol novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, dicyclopentadiene type epoxy resins, Heterocyclic epoxy resins such as triphenolmethane type epoxy resins and triazine nucleus-containing epoxy resins, stilbene type bifunctional epoxy compounds, naphthalene type epoxy resins, condensed ring aromatic hydrocarbon modified epoxy resins, alicyclic type epoxy resins, etc. It is done.

  As the phenol resin curing agent of component (B) used in the present invention, as long as it has two or more phenolic hydroxyl groups in the molecule that can react with the epoxy group in the epoxy resin of component (A), Used without limitation. Specifically, phenol novolac resins, cresol novolac resins and other novolac phenol resins obtained by reacting phenols such as phenol and alkylphenol with formaldehyde or paraformaldehyde, and epoxidizing or butylated these novolac phenol resins. Modified novolac type phenol resins, dicyclopentadiene modified phenol resins, paraxylene modified phenol resins, phenol aralkyl resins, naphthol aralkyl resins, triphenol alkane type phenol resins, polyfunctional type phenol resins and the like are used. These may be used individually by 1 type, and may mix and use 2 or more types.

  The blending amount of the (B) component phenolic resin curing agent is the number of phenolic hydroxyl groups (b) of the (B) component phenolic resin curing agent with respect to the epoxy group number (a) of the (A) component epoxy resin. A range in which the ratio (b) / (a) is 0.3 to 1.5 is preferable, and a range in which the ratio (b) / (a) is 0.5 to 1.2 is more preferable. When the ratio (b) / (a) is less than 0.3, the moisture resistance reliability of the cured product is lowered. Conversely, when the ratio (b) / (a) is more than 1.5, the strength of the cured product is lowered.

  The (C) component curing accelerator used in the present invention is particularly limited as long as it accelerates the curing reaction of the (A) component crystalline epoxy resin and the (B) component phenol resin curing agent. Used without. Specific examples include imidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-undecylimidazole, 1,2-dimethylimidazole, 2,4-dimethylimidazole, 2- Phenylimidazole, 2-phenyl-4-methylimidazole, 4-methylimidazole, 4-ethylimidazole, 2-phenyl-4-hydroxymethylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phen Ruimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2- Undecylimidazolium trimellitate, 1-cyanoethyl-2-phenyl-4,5-di (cyanoethoxy) methylimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 1-benzyl-2-phenyl Imidazole hydrochloride, 1-benzyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino- 6- [2'-Undecylimidazolyl- (1 ')]-d Ru-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'- Imidazoles such as methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenylimidazoline; 1,8-diazabicyclo [5, Diazabicyclo such as 4,0] undecene-7 (DBU), 1,5-diazabicyclo [4,3,0] nonene, 5,6-dibutylamino-1,8-diazabicyclo [5,4,0] undecene-7 Compounds and salts thereof; triethylamine, triethylenediamine, benzyldimethylamine, α-methylbenzyldimethylamine, trieta Tertiary amines such as allamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; trimethylphosphine, triethylphosphine, tributylphosphine, diphenylphosphine, triphenylphosphine, tri (p-methylphenyl) phosphine, tri (nonylphenyl) Organic phosphine compounds such as phosphine, methyldiphenylphosphine, dibutylphenylphosphine, tricyclohexylphosphine, bis (diphenylphosphino) methane, 1,2-bis (diphenylphosphino) ethane; tetraphenylphosphonium tetraphenylborate, triphenylphosphinetetra Examples thereof include tetra- or triphenylboron salts such as phenyl borate and triphenylphosphine triphenylborane. Among these, imidazoles are preferable from the viewpoint of good fluidity and moldability. These may be used individually by 1 type, and may mix and use 2 or more types.

  The blending amount of this component (C) curing accelerator is preferably in the range of 0.1 to 5 mass% with respect to the entire composition. If the blending amount is less than 0.1% by mass, the curability is not very effective. On the contrary, if it exceeds 5% by mass, the moisture resistance reliability of the molded product may be lowered.

  The inorganic filler of component (D) used in the present invention can be used without particular limitation as long as it is generally used in this type of resin composition. Specific examples thereof include, for example, fused silica, crystalline silica, crushed silica, synthetic silica, alumina, titanium oxide, oxide powder such as magnesium oxide, hydroxide powder such as aluminum hydroxide and magnesium hydroxide, boron nitride, Examples thereof include nitride powders such as aluminum nitride and silicon nitride. These inorganic fillers may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  (D) As an inorganic filler of a component, a silica powder is especially preferable from a viewpoint which improves the handleability and moldability of the resin sheet for semiconductor sealing, and fused silica is especially preferable. When silica other than fused silica is used, the proportion is preferably less than 30% by mass of the entire silica powder. These silica powders preferably have an average particle size of 0.5 to 40 μm, more preferably 5 to 30 μm, and a maximum particle size of 105 μm or less. When the average particle size is less than 0.5 μm, the fluidity of the resin composition is lowered and the moldability may be impaired. On the other hand, if the average particle diameter exceeds 40 μm, the molded product may be warped or the dimensional accuracy may be reduced. On the other hand, if the maximum particle size exceeds 105 μm, the moldability may be reduced. The average particle size of the silica powder can be determined by, for example, a laser diffraction particle size distribution measuring device, and the average particle size is a particle size (d50) in which the integrated volume is 50% in the particle size distribution measured by the same device. ).

  (D) The compounding quantity of the inorganic filler of a component has the preferable range of 70-92 mass% with respect to the whole composition, and the range of 75-90 mass% is more preferable. If it is less than 70% by mass, the coefficient of linear expansion increases and the dimensional accuracy, moisture resistance, mechanical strength, etc. of the molded product is reduced. If it exceeds 95% by mass, the resin sheet for semiconductor encapsulation tends to break. . In addition, the melt viscosity increases and the fluidity decreases, and the moldability may decrease.

  Examples of the polymer cationic dispersant (E) used in the present invention include those having a main skeleton of polycarboxylic acid or polyamine. Those having polyamine as the main skeleton are particularly preferred. Examples of commercially available polymer cationic dispersants having polyamine as the main skeleton include KD-1 (trade name) manufactured by Croda Japan Co., Ltd. Moreover, when the commercial item of the polymeric cation type | system | group dispersing agent which uses polycarboxylic acid as a main skeleton is illustrated, KD-9 (brand name) by a Croda Japan Co., Ltd. will be mentioned, for example. One type of polymeric cationic dispersant may be used alone, or two or more types may be mixed and used.

  By using the polymeric cationic dispersant together with the crystalline epoxy resin of the component (A), the melt viscosity of the composition when the inorganic filler of the component (D) is highly filled can be maintained in a suitable range. It becomes easier and the heat resistance of the resin sheet for semiconductor encapsulation can be further enhanced.

  In order to acquire the said effect, the range of 0.05-5 mass% is preferable with respect to the whole composition, and the compounding quantity of the polymeric cationic dispersing agent of (E) component is the range of 0.1-2 mass% Is more preferable. If it is less than 0.05% by mass, the above-mentioned effects cannot be obtained sufficiently, and the resin sheet for semiconductor encapsulation becomes sticky, making it difficult to release from the mold.

  In the sealing resin composition of the present invention, in addition to the components described above, a coupling agent that is generally blended with this type of composition within a range not inhibiting the effects of the present invention; synthetic wax, natural wax, Mold release agents such as metal salts such as higher fatty acids and higher fatty acids; Colorants such as carbon black and cobalt blue; Low stress imparting agents such as silicone oil and silicone rubber, hydrotalcites, ion scavengers, etc. Can do.

  As the coupling agent, an epoxy silane, amino silane, ureido silane, vinyl silane, alkyl silane, organic titanate, aluminum alcoholate, or the like is used. These may be used individually by 1 type, and 2 or more types may be mixed and used for them. From the viewpoints of moldability, flame retardancy, curability, etc., aminosilane coupling agents are preferred, and in particular, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane. Γ-aminopropylmethyldiethoxysilane and the like are preferable.

  The amount of the coupling agent to be blended is preferably in the range of 0.01% by mass to 3% by mass and more preferably in the range of 0.1% by mass to 1% by mass of the entire composition. If it is less than 0.01% by mass of the whole composition, it is not very effective for improving moldability. Conversely, if it exceeds 3% by mass, foaming may occur during molding and voids or surface swelling may occur in the molded product. .

  In preparing the epoxy resin composition, (A) an epoxy resin containing a crystalline epoxy resin, (B) a phenol resin curing agent, (C) a curing accelerator, (D) an inorganic filler, (E) a polymer cation After sufficiently mixing (dry blending) the system dispersant and the various components blended as necessary with a mixer or the like, the mixture is melt-kneaded with a kneading apparatus such as a hot roll or a kneader, cooled, and then appropriately sized. Grind into. The pulverization method is not particularly limited, and general pulverizers such as a speed mill, a cutting mill, a ball mill, a cyclone mill, a hammer mill, a vibration mill, a cutter mill, and a grinder mill can be used. A speed mill is preferable. The pulverized product can then be adjusted to a particle aggregate having a predetermined particle size distribution by sieving classification, air classification or the like.

The resin sheet for encapsulating a semiconductor according to the present invention is obtained by heating and melting and compressing the epoxy resin composition prepared as described above between pressure members to form a sheet.
More specifically, after the resin layer is formed by supplying the epoxy resin composition so as to have a substantially uniform thickness on a heat-resistant release film such as a polyester film, the resin layer is heated and softened. Roll with a roll and hot press. At that time, a heat-resistant film such as a polyester film is also disposed on the resin layer. Thus, after rolling a resin layer to desired thickness, it cools and solidifies, a heat resistant film is peeled, and also it cut | disconnects to a desired magnitude | size and shape as needed. Thereby, the resin sheet for semiconductor sealing is obtained. In addition, the heating temperature at the time of softening a resin layer is about 80-150 degreeC normally. If the heating temperature is less than 80 ° C., the melt mixing becomes insufficient, and if it exceeds 150 ° C., the curing reaction proceeds excessively, and the resin sealing moldability may be lowered.

The semiconductor sealing resin sheet has a melt viscosity of 2 to 50 Pa · s measured by a Koka flow tester under the conditions of a temperature of 175 ° C. and a load of 10 kg (shear stress 1.23 × 10 ⁵ Pa). It is preferably 3 to 20 Pa · s. If the melt viscosity is less than 2 Pa · s, burrs are likely to occur, and if it exceeds 50 Pa · s, the filling property is lowered, and voids or unfilled portions may be generated.

  The semiconductor sealing resin sheet preferably has a thickness of 0.1 to 2 mm. If the thickness is 0.1 mm or more, there is no risk of cracking, excellent handleability, and easy loading into a compression molding die. Further, if the thickness is 2 mm or less, the melting of the resin sheet in the mold is delayed at the time of semiconductor sealing, and molding does not become defective.

The resin-encapsulated semiconductor device of the present invention can be manufactured by encapsulating a semiconductor element by compression molding using the resin sheet for semiconductor encapsulation. Hereinafter, an example of the method will be described.
First, a substrate on which a semiconductor element is mounted is placed between the two resin sheets for semiconductor sealing in a cavity of a compression molding die, and compression molding is performed at a predetermined temperature and a predetermined pressure. The molding conditions are preferably a temperature of 100 to 190 ° C. and a pressure of 4 to 12 MPa. After molding, post-curing is performed at a temperature of 130 to 190 ° C. for about 2 to 8 hours. Thereby, the resin-encapsulated semiconductor device is completed.

  The resin-encapsulated semiconductor device thus obtained is easy to handle even if it is thin, and is sealed by compression molding using a resin sheet for semiconductor encapsulation that is excellent in moldability. Quality and high reliability can be achieved.

  The semiconductor element to be sealed in the semiconductor device of the present invention is not particularly limited, and examples thereof include IC, LS, diode, thyristor, transistor, etc., but are difficult with conventional sealing materials. The present invention is particularly useful in the case of a semiconductor element having a thickness after sealing of 0.1 to 1.5 mm.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples at all. The materials used in the following examples and comparative examples are as shown in Table 1.

Example 1
Using the crystalline epoxy resin I, the phenol resin I, the fused silica I, II, the polymeric cationic dispersant I, the curing accelerator, the colorant, and the release agent shown in Table 1, the composition shown in Table 2 is obtained. Each raw material was mixed at room temperature, and then kneaded at 80 to 130 ° C. using a hot roll. After cooling, an epoxy resin composition was prepared by pulverization using a speed mill.

The obtained epoxy resin composition is sandwiched between release films made of polyester, placed between 80 ° C. hot plates, heated and pressed at a pressure of 10 MPa for 1 minute, and a resin sheet for semiconductor encapsulation having a thickness of 0.5 mm Made,
Furthermore, the semiconductor chip was sealed using the obtained resin sheet for semiconductor sealing. That is, first, a 150 mm × 30 mm sheet was cut out from the semiconductor sealing resin sheet. This sheet is placed in a compression mold, a substrate on which a semiconductor chip is mounted is overlaid thereon, and the above sheet is overlaid thereon, and compression molding is performed under a pressure of 8.0 MPa and at 175 ° C. for 30 minutes. did. Thereafter, post-curing was performed at 175 ° C. for 4 hours to manufacture a semiconductor device.

(Examples 2-5, Comparative Examples 1-4)
An epoxy resin composition was prepared in the same manner as in Example 1 except that the composition was changed as shown in Table 2, and then the semiconductor sealing resin having a thickness of 0.5 mm was obtained using the obtained composition. A sheet was manufactured, and a semiconductor device was manufactured using the sheet.

  Various characteristics of the epoxy resin composition, the semiconductor sealing resin sheet, and the semiconductor device (product) obtained in each of the above Examples and Comparative Examples were evaluated by the following methods. The results are also shown in Table 2.

<Resin composition>
(1) Spiral flow Using a mold conforming to the EMMI standard, transfer molding was performed at a temperature of 175 ° C. and a pressure of 9.8 MPa, and measurement was performed.
(2) Gel time In accordance with the gelation time A method defined in 7.5.1 of JIS C 2161, about 1 g of the epoxy resin composition is applied on a hot plate at 175 ° C., and stirred with a stirring rod. The time until it became a gel and could not be stirred was measured.
(3) Koka type flow viscosity Flow characteristics evaluation device (product name, flow tester CFT-500, manufactured by Shimadzu Corporation), temperature 175 ° C., load 10 kg (under an environment of shear stress 1.23 × 10 ⁵ Pa) The melt viscosity was measured.
(4) Glass transition point Tg
A stick-shaped sample was prepared from the cured product obtained by heating at 175 ° C. for 3 minutes and the temperature was increased by a thermal analysis apparatus (TMA) (product name: TMA SS-150, manufactured by Seiko Instruments Inc.). The TMA chart was measured by raising the temperature under the conditions of ° C./min, and obtained from the intersection of two tangents.
(5) Bending strength / flexural modulus A sample prepared in the same manner as in (4) was measured at a temperature of 25 ° C. in accordance with JIS K 6911.
(6) Water absorption rate Compression molding under a pressure of 12 MPa at 175 ° C. for 2 minutes, followed by post-curing at 175 ° C. for 8 hours to obtain a disk-shaped cured product having a diameter of 50 mm and a thickness of 3 mm. This was allowed to stand in saturated steam at 127 ° C. and 0.25 MPa for 24 hours, and the increased weight was determined and calculated from the following formula.
Water absorption = increased weight / initial weight of cured product

<Sheet (Resin Sheet for Semiconductor Encapsulation)>
(1) Flexibility A semiconductor sealing resin sheet having a width of 10 mm, a length of 50 mm, and a thickness of 0.5 mm is cut out, a part of 15 mm is clamped from one end, and is set to a height of 18 mm on a gantry, and the sheet with its own weight The time until one end of the plate contacts the top surface of the gantry was measured (initial).
Separately, after cutting out a semiconductor sealing resin sheet having a width of 10 mm, a length of 50 mm, and a thickness of 0.5 mm and leaving it to stand at 25 ° C. for 168 hours, similarly, a 15 mm portion from one end was clamped, The height was set to 18 mm on the gantry, and the time until one end of the sheet contacted the upper surface of the gantry under its own weight was measured.

<Product (semiconductor device)>
(1) Reflow resistance (MSL test)
The semiconductor device was subjected to a moisture absorption treatment at 85 ° C. and 85% RH for 72 hours, and then a test (MSL test) in which heating was performed for 90 seconds in an infrared reflow oven at 240 ° C. to determine the incidence of defects (peeling and cracking). The number of samples was examined (20).
(2) Moisture resistance reliability (pressure cooker test: PCT)
In a pressure cooker, water was absorbed for 72 hours under the conditions of 127 ° C. and 0.25 MPa, and then vapor reflow was performed at 240 ° C. for 90 seconds to examine the incidence of defects (open defects) (number of samples = 20). .
(3) High temperature storage reliability (Advanced accelerated life test: HAST)
The sample was left in a constant temperature bath at 180 ° C. for 1000 hours, and the occurrence rate of defects (open defects) was examined (number of samples = 20).

As is clear from Table 2, the resin sheet for encapsulating a semiconductor according to the example of the present invention had flexibility even when left at room temperature for a long time, and had good handleability.
Moreover, the semiconductor device manufactured using such a resin sheet for encapsulating semiconductors has obtained good results in any of the MSL test, the pressure cooker test, and the advanced accelerated life test. It was confirmed that the semiconductor device has high reliability.

  The resin sheet for encapsulating a semiconductor of the present invention is excellent in handleability and moldability even when the thickness is reduced. Therefore, it is useful as a sealing material for compression molding of a thinned semiconductor element, and a high-quality and highly reliable resin-encapsulated semiconductor device can be manufactured.

Claims (6)

(A) Epoxy resin containing crystalline epoxy resin, (B) Phenolic resin curing agent, (C) Curing accelerator, (D) Inorganic filler, and (E) Epoxy whose essential component is a polymeric cationic dispersant An epoxy resin composition, which is a resin composition, wherein the polymer cationic dispersant is a polymer cationic dispersant composed of a hydrocarbon graft copolymer having a polyamine as a main chain, is formed into a sheet shape. The resin sheet for semiconductor sealing characterized by becoming.   (A) The crystalline epoxy resin contains a biphenyl type epoxy resin, The resin sheet for semiconductor sealing of Claim 1 characterized by the above-mentioned.   (D) The inorganic sealing material contains silica powder, The resin sheet for semiconductor sealing of Claim 1 or 2 characterized by the above-mentioned.   (D) Content of an inorganic filler is 70-92 mass% of the whole composition, The resin sheet for semiconductor sealing of any one of the Claims 1 thru | or 3 characterized by the above-mentioned. (E) Content of a high molecular cationic dispersing agent is 0.05-5 mass% of the whole composition, The resin sheet for semiconductor sealing of any one of the Claims 1 thru | or 4 characterized by the above-mentioned. .   A resin-encapsulated semiconductor device, wherein a semiconductor element is encapsulated by compression molding using the resin sheet for encapsulating a semiconductor according to any one of claims 1 to 5.