JP5519189B2 - Adhesive sheet for dicing electronic components - Google Patents

Description

  The present invention relates to an adhesive sheet for dicing an electronic component used for dicing an electronic component having a wiring board such as a semiconductor package.

  2. Description of the Related Art Conventionally, a semiconductor wafer made of silicon, gallium, arsenic, or the like is manufactured in a large diameter state, cut and separated (diced) into element pieces, further mounted, and then packaged. In this packaging, usually, a plurality of chips are packaged at a time, and this semiconductor package is further diced and picked up into individual semiconductor chips. The semiconductor package is subjected to a dicing process, a cleaning process, an expanding process, and a pick-up process in a state where the semiconductor package is adhered and fixed to the adhesive sheet. As the pressure-sensitive adhesive sheet, a sheet in which an acrylic pressure-sensitive adhesive is provided in an amount of about 1 μm to 200 μm on a base made of a plastic film is generally used.

  The dicing process of a semiconductor package is usually performed using a round blade (hereinafter referred to as a dicing blade) that moves while rotating. At that time, the cutting of the dicing blade is performed so as to reach the inside of the base material of the pressure-sensitive adhesive sheet for holding the semiconductor package. At this time, when cutting is performed to the inside of the base material of the pressure-sensitive adhesive sheet, cutting waste is generated in which the plastic film as the base material itself becomes a thread. In recent years, the thinning of semiconductor packages has progressed, and thread-like scraps that have not been a problem in the past have adhered to the electrodes on the surface of the semiconductor package and have increased the cause of mounting defects. For this reason, development of the adhesive sheet for dicing of the electronic component which suppressed generation | occurrence | production of filamentous waste more is desired.

  In addition, the generation | occurrence | production mechanism of a filamentous waste is as follows. That is, as disclosed in Japanese Patent Application Laid-Open No. 2001-72947 (Patent Document 1), the dicing blade is heated by friction when cutting the object to be cut, and the resin constituting the base material by cutting into the base material. Melts. The melted resin is wound up by the rotation of the dicing blade, and then cooled and solidified with cutting cooling water to become thread-like waste.

  In the conventional dicing of silicon wafers, for example, polypropylene as described in JP-A-11-43656 (Patent Document 2) and JP-A-2003-7654 (Patent Document 3) is used as a main constituent. The substrate was effective in suppressing the generation of filamentous waste. It is presumed that this was because polypropylene had a high melting point and was hardly melted by a heated dicing blade. However, even when such an adhesive sheet of a base material is used for dicing a semiconductor package, generation of thread-like waste derived from the base material still occurred.

  Japanese Patent Application Laid-Open No. 2006-342330 (Patent Document 4) has a multilayer structure having a layer containing an ethylene-based resin having a melting point of 95 ° C. or lower and is crosslinked on the side in contact with the pressure-sensitive adhesive layer. A pressure-sensitive adhesive sheet for dicing having a layer having a structure has been proposed, and the occurrence of filamentous waste is suppressed by actively melting the base material during dicing and scattering the base material like a liquid. However, since there is a problem that a large amount of filamentous waste is generated depending on the dicing conditions, a pressure-sensitive adhesive sheet for dicing that can further suppress the generation of filamentous waste is desired.

JP 2001-72947 A Japanese Patent Laid-Open No. 11-43656 JP 2003-7654 A JP 2006-342330 A

  An object of the present invention is to provide a pressure-sensitive adhesive sheet for dicing an electronic component that can reduce the generation of thread-like waste when dicing an electronic component having a wiring board such as a semiconductor package.

That is, the present invention is an electronic component-sensitive adhesive sheet for dicing to be used for dicing the electronic component having a wiring substrate, have at least one side pressure-sensitive adhesive layer, a substrate comprising a (meth) acrylic resin of MFR at 120 ° C. is 0 g / 10min, split resistance relates dicing adhesive sheet 5% to 300% der Ru electronic components at 120 ° C..

  In the present invention, the physical property of the substrate at 120 ° C. is specified because it was confirmed that the dicing blade rotating at a high speed at the time of cutting the substrate is 90 ° C. or more in the dicing of the semiconductor package. It is. In addition, by lowering the melting point of the base material lower than the temperature at the time of dicing, if the base material is actively melted at the time of dicing, the melted base material is cooled and solidified by cutting cooling water, and filamentous waste may be generated. Since it was confirmed, it was decided to use a substrate that does not melt during dicing.

That is, by setting the MFR at 120 ° C. of the base material of the adhesive sheet for dicing of the electronic component of the present invention to 0 g / 10 min, it is possible to suppress melting of the base material when the dicing blade cuts into the base material. Can be suppressed.

  Moreover, it is preferable that the tearability at 120 ° C. of the base material of the adhesive sheet for dicing electronic components is 5% to 300%, more preferably 10% to 200%, and further preferably 10% to 100%. When the tearability of the base material at 120 ° C. is in this range, the cutting waste of the base material is separated from the base material before the base material is stretched by the dicing blade. be able to. On the other hand, when the tearability at 120 ° C. of the substrate exceeds 300%, the substrate is difficult to tear, so that the substrate stretched by the dicing blade is separated from the filament waste that has been cooled and solidified by cutting cooling water. There is a risk of exposure to the surface of the semiconductor package. Moreover, since the base material is easy to tear when the tearability at 120 ° C. of the base material is less than 5%, the wall surface of the dicing line is easily cracked by the stress at the time of dicing, and there is a possibility that thread waste is generated.

  Further, in the present invention, the substrate is composed of at least two layers, and the MFR at 120 ° C. of the substrate on the side in contact with the pressure-sensitive adhesive layer on which the electronic component is adhered and held is 0 g / 10 min. The present invention relates to a pressure-sensitive adhesive sheet for dicing an electronic component, wherein the tearability at 5 ° C. is 5% to 300%.

  The substrate of the pressure-sensitive adhesive sheet for dicing of the electronic component of the present invention may have a multilayer structure, and the substrate on the side in contact with the pressure-sensitive adhesive layer has an MFR at 120 ° C. of 0 g / 10 min and tearability at 120 ° C. Is preferably 5% to 300%, more preferably 10% to 200%, still more preferably 10% to 100%, and the substrate on the side in contact with the pressure-sensitive adhesive layer is in such a range. Generation | occurrence | production of a filamentous waste can be suppressed. Moreover, each layer of a base material may be comprised with the same base material, respectively, and the layer comprised with the different base material may be laminated | stacked. The base material on the side in contact with the pressure-sensitive adhesive layer is made of a base material that suppresses the generation of filamentous waste during dicing, and the other layers are made of a highly stretchable base material for the dicing process. In addition to suppressing the generation of filamentous waste, a useful pressure-sensitive adhesive tape can be produced even in the process of expanding the pressure-sensitive adhesive tape after dicing.

  The pressure-sensitive adhesive sheet for dicing of an electronic component of the present invention has a configuration in which a pressure-sensitive adhesive layer is provided on one side of a substrate.

  The base material used for the pressure-sensitive adhesive sheet for dicing of the electronic component of the present invention preferably has an MFR at 120 ° C. of 0 g / 10 min and a tearability at 120 ° C. of 5% to 300%.

  The base material is not particularly limited as long as it has the mechanical properties in the scope of the claims, and any material, molecular weight distribution, molecular structure, manufacturing method, additive type may be used. Without any problem, specifically polyester such as polyvinyl chloride, polyvinylidene chloride, polyethylene terephthalate, polyimide, polyether ether ketone; low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, Polyolefin such as random copolymer polypropylene, block copolymer polypropylene, homopolypropylene, polybutene, polymethylpentene; polyurethane, ethylene-vinyl acetate copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meta Acrylic acid ester (Randa , Alternating) copolymer, ethylene - butene copolymer, ethylene - hexene copolymer, fluorocarbon resins and those formed by polymers, such as cellulose-based resin and a cross-linked product thereof. These may be a single layer or a multilayer structure. The thickness of the substrate may be at least thicker than the cutting depth of the dicer and can be easily wound into a roll, and the thickness of the substrate is preferably 80 μm to 300 μm, more preferably Is 80 μm to 250 μm.

  The base material used for the pressure-sensitive adhesive sheet for dicing of the electronic component of the present invention is composed of 80% to 10% by weight of a styrene elastomer resin (hereinafter referred to as SE resin) and a (meth) acrylic acid alkyl ester monomer and diene. It is preferable to use a film containing a blend resin composed of 20% by weight to 90% by weight of a terpolymer resin (particularly butadiene) and a styrene monomer (hereinafter referred to as MBS ternary resin). . That is, the base material of the present invention is preferably a single layer or a film having two or more layers including the blend resin film. The (meth) acrylic acid alkyl ester monomer means a methacrylic acid alkyl ester monomer or an acrylic acid alkyl ester monomer.

(1) Single layer film: (A)
As an aspect of the substrate used for the pressure-sensitive adhesive sheet for dicing of electronic parts of the present invention, a single layer film of layer (A) comprising 80 wt% to 10 wt% of SE resin and 20 wt% to 90 wt% of MBS ternary resin Is mentioned.

  The SE resin used in the base material used in the pressure-sensitive adhesive sheet for dicing of the electronic component of the present invention mainly has a function of imparting the expandability (elasticity) necessary for the base material. The SE resin is a copolymer composed of a styrene monomer and a diene monomer, or a hydrogenated product thereof. The SE resin is a soft thermoplastic resin (thermoplastic elastomer) having elasticity, and the film itself can be formed into a film.

  Examples of the styrene monomer constituting the SE resin include styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N, N-dimethyl-p-aminoethylstyrene, N , N-diethyl-p-aminoethylstyrene, and the like. These may be used alone or in combination of two or more. Styrene is particularly preferred.

  The diene monomer constituting the SE resin is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2, 3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and the like, with 1,3-butadiene and isoprene being particularly common Is mentioned. These may be used alone or in combination of two or more. In particular, butadiene is preferred.

  The content of the styrene monomer unit in the SE resin is usually 8% to 75% by weight, preferably 10% to 70% by weight, and the content of the diene monomer unit is usually 25%. % By weight to 92% by weight, preferably 20% to 90% by weight. The content of styrene monomer units is measured using an ultraviolet spectrophotometer or a nuclear magnetic resonance apparatus (NMR), and the content of diene monomer units is measured using a nuclear magnetic resonance apparatus (NMR). be able to.

  The SE resin has a hardness (JIS K6253 durometer type A) of about 40 to 90, preferably about 50 to 80. Its specific gravity (ASTM D297) is about 0.85 to 1.0, MFR (ASTM D1238: 230 ° C., 21.2 N) is about 3 g / 10 min to 6 g / 10 min, and the glass transition temperature (Tg) is The value measured by differential scanning calorimetry (DSC method) is about −50 ° C. to 30 ° C., and preferably about −40 ° C. to 20 ° C.

  The SE resin has a weight average molecular weight (Mw) of, for example, about 100,000 to 500,000, preferably about 150,000 to 300,000. The weight average molecular weight can be measured using commercially available standard gel permeation chromatography (GPC).

  The SE resin used in the present invention may be a copolymer comprising a styrene monomer and a diene monomer, but since a double bond derived from a diene monomer remains, it is known. It is good to saturate by hydrogenation (for example, nickel catalyst etc.) by the method. This is because it becomes a more stable resin excellent in heat resistance, chemical resistance, durability and the like. The hydrogenation rate of the SE resin is 85% or more, preferably 90% or more, more preferably 95% or more of the double bond based on the conjugated diene compound in the copolymer. This hydrogenation rate can be measured using a nuclear magnetic resonance apparatus (NMR).

  Examples of the SE resin used in the present invention include a hydrogenated random copolymer composed of a styrene monomer and a diene monomer (hereinafter also referred to as “hydrogenated random copolymer”), a styrene monomer And a hydrogenated product of a block copolymer composed of a monomer and a diene monomer (hereinafter also referred to as “hydrogenated block copolymer”), or a blend thereof.

Specific examples of the hydrogenated random copolymer include a styrene monomer unit represented by the formula: —CH (C ₆ H ₅ ) CH ₂ — and a formula: —CH ₂ CH ₂ CH ₂ CH ₂ —. And a hydrogenated random copolymer in which an ethylene unit and a butylene unit represented by the formula: —CH (C ₂ H ₅ ) CH ₂ — are randomly bonded.

  In the hydrogenated random copolymer, the content of the styrenic monomer unit is about 60% to 75% by weight, preferably about 65% to 70% by weight. The glass transition temperature (Tg) is about 0 ° C to 30 ° C, preferably about 10 ° C to 20 ° C. The weight average molecular weight is about 100,000 to 500,000, preferably about 150,000 to 300,000.

  Such a hydrogenated random copolymer can be produced, for example, by the method described in JP-A No. 2004-59741 or according thereto.

  On the other hand, as a hydrogenated block copolymer, one having a block segment derived from a styrene monomer at one end or both ends of the copolymer and further having a block segment derived from a diene monomer, or these Blended ones are listed.

The hydrogenated block copolymer has, for example, a block segment derived from a styrenic monomer represented by the formula: —CH (C ₆ H ₅ ) CH ₂ — at one end of the copolymer, The block segment includes an ethylene unit represented by the formula: —CH ₂ CH ₂ CH ₂ CH ₂ — and / or a butylene unit represented by the formula: —CH (C ₂ H ₅ ) CH ₂ —. And a hydrogenated block copolymer having a segment containing an ethylene unit represented by the formula: —CH ₂ CH ₂ CH ₂ CH ₂ — at the other end of the copolymer.

  In the hydrogenated block copolymer, the content of the styrenic monomer unit is about 8 wt% to 50 wt%, preferably about 10 wt% to 40 wt%. The glass transition temperature (Tg) is about −50 ° C. to 0 ° C., preferably about −40 ° C. to −10 ° C. The weight average molecular weight is about 100,000 to 500,000, preferably about 150,000 to 300,000. SEBC is exemplified as a specific example of the hydrogenated block copolymer having the above-described characteristics.

Alternatively, as a hydrogenated block copolymer, for example, at both ends of the copolymer, it has a block segment derived from a styrenic monomer represented by the formula: —CH (C ₆ H ₅ ) CH ₂ —, In the middle, a block segment containing an ethylene unit represented by the formula: —CH ₂ CH ₂ CH ₂ CH ₂ — and / or a butylene unit represented by the formula: —CH (C ₂ H ₅ ) CH ₂ — Examples thereof include a hydrogenated block copolymer.

  In the hydrogenated block copolymer, the content of the styrenic monomer unit is about 8 wt% to 50 wt%, preferably about 10 wt% to 40 wt%. The glass transition temperature (Tg) is about −50 ° C. to 0 ° C., preferably about −40 ° C. to −10 ° C. The weight average molecular weight is about 100,000 to 500,000, preferably about 150,000 to 300,000. SEBS is exemplified as a specific example of the hydrogenated block copolymer having the above characteristics.

  Among SE resins, a hydrogenated random copolymer is not as elastic as a hydrogenated block copolymer, but has an advantage that dicing can be easily cut by a dicer. On the other hand, the degree of blocking between films tends to be stronger in hydrogenated random copolymers than in hydrogenated block copolymers. Therefore, in order to have both the ease of cutting and the blocking resistance, a blended SE resin comprising a hydrogenated random copolymer as a main component and blended with a hydrogenated block copolymer is suitable. Can be used for

  The weight ratio of the hydrogenated random copolymer to the hydrogenated block copolymer in the blended SE resin is, for example, about 55 wt% to 80 wt% for the hydrogenated random copolymer and 45 wt% for the hydrogenated block copolymer. % To about 20% by weight is preferable.

  The MBS ternary resin used in the base material of the present invention suppresses blocking of the film, suppresses dicing waste (filamentous waste), and plays a role of imparting appropriate waist hardness to the film.

  The MBS ternary resin is a copolymer of a (meth) acrylic acid alkyl ester monomer, a diene monomer (particularly butadiene), and a styrene monomer as described above. Specifically, the MBS ternary resin comprises (meth) acrylic acid alkyl ester (MAA) monomer units of 30% to 62% by weight, diene monomer units of 3% to 35% by weight, styrene It is a copolymer composed of 35% to 67% by weight of monomer units. Here, the alkyl of the alkyl ester of the MAA monomer unit is generally an alkyl having 1 to 5 carbon atoms (particularly methyl, ethyl, etc.), and the hardness tends to decrease as the carbon number increases. Specific examples of the MAA monomer unit include methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, and the like. In addition, what was described as a raw material of said SE resin can be used for a diene monomer and a styrene monomer.

  The MBS ternary resin is a hard resin, and its hardness (JIS K6253 durometer type D) is about 20 to 50, preferably 30 to 40. Its specific gravity (ASTM D297) is about 1.09 to 1.11, MFR (ASTM D1238: 230 ° C., 21.2 N) is about 2.0 g / 10 min to 6.0 g / 10 min, and the glass transition temperature ( Tg) is a value measured by a differential scanning calorimetry (DSC method) and is about 80 ° C. to 95 ° C., preferably about 85 ° C. to 90 ° C. The weight average molecular weight (Mw) of the MBS ternary resin is about 100,000 to 400,000, preferably about 100,000 to 200,000. The measurement is based on the GPC method.

  The base material comprising the single layer (A) of the present invention is characterized in that the soft SE resin and the hard MBS ternary resin are blended at a predetermined ratio, and the blend ratio is the same as that of the SE resin. 80 wt% to 10 wt%, preferably 70 wt% to 45 wt%, and MBS ternary resin is 20 wt% to 90 wt%, preferably 30 wt% to 55 wt%. Thereby, a remarkable effect that dicing waste is not generated, uniform and appropriate expandability, and excellent blocking resistance between films is exhibited. When the SE resin exceeds 80% by weight and the MBS ternary resin is less than 20% by weight, the effect of inhibiting blocking is particularly lowered, and the appropriate waist hardness tends to be lowered. On the other hand, when the SE resin is less than 10% by weight and the MBS ternary resin is more than 90% by weight, it is difficult to uniformly expand the film and the hardness of the waist tends to be hard.

  The thickness of the base material composed of the single layer (A) of the present invention may be at least thicker than the cutting depth of the dicer and can be easily wound in a roll shape. 80 micrometers-300 micrometers are preferable, More preferably, they are 80 micrometers-250 micrometers.

  Next, the manufacturing method of the single layer base material of this invention is demonstrated. SE resin 80 wt% to 10 wt% and MBS ternary resin 20 wt% to 90 wt% are uniformly blended and dispersed by dry blending or melt kneading. Next, the obtained mixture is supplied to a screw type extruder, extruded from a single-layer T-die at 200 ° C. to 225 ° C., and cooled while passing through a cooling roll at 50 ° C. to 70 ° C. Taking up substantially unstretched.

  Here, the reason why the film is substantially unstretched is to effectively extend the film after dicing. This substantially non-stretching includes non-stretching or slight stretching that does not adversely affect the expansion of the dicing film. In general, the film may be pulled to such an extent that no sagging occurs when the film is taken up.

(2) Three-layer film: (A) / (B) / (A)
As another aspect of the substrate of the present invention, the layer (A) and a layer (B) composed of 100 wt% to 80 wt% of the SE resin and 0 wt% to 20 wt% of the MBS ternary resin are A substrate for dicing composed of at least three layers laminated in the order of A) / (B) / (A) can be mentioned.

  First, the resin composition constituting the layer (A) is the same as described above.

  The layer (B) corresponding to the intermediate layer contains SE resin in an amount of 80% by weight or more, preferably 85% by weight or more, and contains MBS ternary resin in an amount of 20% by weight or less, preferably 15% by weight or less. The layer (B) imparts extensibility (elasticity) to the base material, but the co-extrusion molding described later is not performed smoothly due to the softness of the SE resin itself, or the thickness of the intermediate layer is increased. When doing so, the hardness of the entire film waist may become softer. Blending the MBS ternary resin up to 20% by weight solves these problems.

  The base material of the present invention is excellent in uniform extensibility because there is no blocking between films by laminating a layer (B) mainly composed of SE resin between two layers (A) having high blocking resistance. Moreover, generation | occurrence | production of dicing waste can also be suppressed further.

  The thickness of the base material composed of the three layers (A) / (B) / (A) of the present invention is at least thicker than the cut depth of the dicer and can be easily wound in a roll shape. It is preferably 80 μm to 300 μm, more preferably 80 μm to 250 μm.

  Next, the manufacturing method of the 3 layer base material of this invention is demonstrated. In this case, a three-layer coextrusion molding method is preferably employed.

  Specifically, 80 wt% to 10 wt% of SE resin and 20 wt% to 90 wt% of MBS ternary resin are dry blended or melt kneaded and uniformly mixed and dispersed to obtain a resin mixture for layer (A). . Also, 100 wt% to 80 wt% of the SE resin and 0 wt% to 20 wt% of the MBS ternary resin are dry blended or melt kneaded and uniformly mixed and dispersed to obtain a resin mixture for the layer (B).

  Next, using three screen type extruders, the resin for the layer (A) is supplied to two units, and the resin for the layer (A) is supplied to one unit at 200 to 225 ° C. ( A) / (B) / (A) are co-extruded from a three-layer T-die in the form of a film and cooled while passing through a cooling roll at 50 ° C. to 70 ° C. so that it is substantially unstretched. Take over. Substantially non-stretching is synonymous with the above (1).

(3) Two-layer film: (A) / (C)
As another embodiment of the base material of the present invention, there is provided a base material comprising at least two layers in which the layer (A) and the layer (C) made of polyethylene resin are laminated by (A) / (C). Can be mentioned.

  First, the resin composition constituting the layer (A) is the same as described above.

  The polyethylene-based resin constituting the polyethylene-based resin layer (C) may be a polymer having a polyethylene unit as a main component, for example, an ethylene homopolymer (ethylene homopolymer), ethylene and an olefin having 3 to 8 carbon atoms. A copolymer with a monomer or a copolymer of ethylene and a (meth) acrylic acid alkyl ester monomer is preferred. The copolymer preferably contains a polyethylene unit of 80% by weight or more, preferably 90% by weight or more.

  Among polyethylene resins, copolymers are preferred, but copolymers of ethylene and (meth) acrylic acid alkyl ester monomers are more preferred. This is because the interlayer adhesion with the layer (A) is excellent. Specifically, ethylene-methyl acrylate copolymer (EMA), ethylene-butyl acrylate copolymer (EBA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer ( EEA) and the like are exemplified. Of these, EMMA is particularly preferable.

  The MFR (ASTM D1238: 230 ° C., 21.2 N) of the polyethylene resin is about 0.5 g / 10 min to 10.0 g / 10 min, and the glass transition temperature (Tg) is determined by the differential scanning calorimetry (DSC method). The measured value is about -130 ° C to 0 ° C, preferably about -120 ° C to -10 ° C.

  The weight average molecular weight (Mw) of the polyethylene resin is about 100,000 to 300,000, preferably about 150,000 to 200,000. The measurement is based on the GPC method.

  The thickness of the base material comprising the two layers (A) / (C) of the present invention can be determined taking into consideration that it is at least thicker than the cutting depth of the dicer and is easily wound in a roll shape. In particular, when the dicer reaches the film C layer, it leads to generation of dicing debris. Therefore, in order to suppress this, it is preferable to make the thickness of the layer (A) larger than the cut depth of the dicer. The thickness of the base material composed of the two layers (A) / (C) of the present invention should be at least thicker than the cut depth of the dicer and can be easily wound into a roll, preferably They are 80 micrometers-300 micrometers, More preferably, they are 80 micrometers-250 micrometers. Among them, the thickness of the layer (A) may be 20% to 90% of the thickness of the base material, more preferably 25% to 80%, and still more preferably 30% to 70%.

  In the base material consisting of two layers according to the present invention, since the polyethylene-based resin layer (C) having high blocking resistance is laminated, the base material for single-layer dicing described in the above (1) and the above (2) Compared to the three-layer substrate described, the blocking resistance is significantly improved. Thus, whether the film is rolled in a roll, rolled in a larger diameter, or rolled at a high temperature, the storage location will be hot, but the blocking concerns that are at issue are completely eliminated.

  Next, the manufacturing method of the 2 layer base material of this invention is demonstrated. In this case, a two-layer coextrusion method is preferably employed.

  Specifically, 80 wt% to 10 wt% of SE resin and 20 wt% to 90 wt% of MBS ternary resin are dry blended or melt kneaded and uniformly mixed and dispersed to obtain a resin mixture for layer (A). . Further, a polyethylene resin is dry blended or melt kneaded to obtain a resin mixture for the layer (C).

  Next, each resin mixture was supplied to two screen extruders and coextruded in a film form from a two-layer T-die at 200 ° C. to 225 ° C., and this was cooled at 50 ° C. to 70 ° C. It is cooled while passing through the glass and taken up substantially unstretched. Substantially non-stretching is synonymous with the above (1).

(4) Three-layer film: (A) / (B) / (C)
As another aspect of the substrate of the present invention, at least three layers (A), (B) and (C) are laminated in the order of (A) / (B) / (C). Examples include a base material composed of layers.

  The resin composition which comprises a layer (A), a layer (B), and a layer (C) is the same as the above.

  The thickness of the base material composed of the three layers (A) / (B) / (C) of the present invention is determined in consideration of being at least thicker than the cutting depth of the dicer and being easily wound into a roll. be able to. In particular, when the dicer reaches the film C layer, it leads to generation of dicing debris. Therefore, in order to suppress this, it is preferable to make the thickness of the layer (A) larger than the cut depth of the dicer. The thickness of the base material comprising the three layers (A) / (B) / (C) of the present invention is at least thicker than the cutting depth of the dicer and can be easily wound into a roll. It is preferably 80 μm to 300 μm, more preferably 80 μm to 250 μm. In this case, the thickness of the layer (A) may be 20% to 90% of the thickness of the substrate, more preferably 25% to 80%, and even more preferably 30% to 70%.

  In the base material composed of three layers according to the present invention, since the polyethylene-based resin layer (C) having high blocking resistance is laminated, the base material for single-layer dicing described in the above (1) and the above (2) Compared to the three-layer substrate described, the blocking resistance is significantly improved. Thus, whether the film is rolled in a roll, rolled in a larger diameter, or rolled at a high temperature, the storage location will be hot, but the blocking concerns that are at issue are completely eliminated.

  Next, the manufacturing method of the 3 layer base material of this invention is demonstrated. In this case, a three-layer coextrusion molding method is preferably employed.

  Specifically, 80 wt% to 10 wt% of SE resin and 20 wt% to 90 wt% of MBS ternary resin are dry blended or melt kneaded and uniformly mixed and dispersed to obtain a resin mixture for layer (A). . Also, 100 wt% to 80 wt% of the SE resin and 0 wt% to 20 wt% of the MBS ternary resin are dry blended or melt kneaded and uniformly mixed and dispersed to obtain a resin mixture for the layer (B). Further, a polyethylene resin is dry blended or melt kneaded to obtain a resin mixture for the layer (C).

  Next, using three screw-type extruders, one unit is the layer (A) resin, the other unit is the layer (B) resin, and the other unit is the layer ( C) resin is supplied and coextruded from a three-layer T-die in the order of (A) / (B) / (C) at 200 ° C. to 225 ° C., and this is 50 ° C. to 70 ° C. It is cooled while passing through a cooling roll and taken up substantially unstretched. Substantially non-stretching is synonymous with the above (1).

  The base material obtained as described above is coated with a known pressure-sensitive adhesive on the layer (A) to form a pressure-sensitive adhesive layer (D), and a release layer (E) is further formed on the pressure-sensitive adhesive layer (D). Once formed, the dicing film of the present invention is manufactured. This film is usually obtained in a rolled state cut into a tape shape.

  As a pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer used in the pressure-sensitive adhesive sheet for dicing of the electronic component of the present invention, a pressure-sensitive pressure-sensitive adhesive that is generally used can be used. Specific examples include various pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, and polyvinyl ethers. In particular, (meth) acrylic polymers are used as base polymers in terms of adhesion to semiconductor wafers and semiconductor packages as objects to be cut, and cleanability of semiconductor wafers after peeling with organic solvents such as ultrapure water and alcohol. A (meth) acrylic pressure-sensitive adhesive is preferred.

  Examples of the (meth) acrylic polymer include (meth) acrylic acid alkyl esters (for example, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, Pentyl ester, isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, isononyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester , Hexadecyl ester, octadecyl ester, eicosyl ester, etc., and an alkyl group having 1 to 30 carbon atoms, particularly a linear or branched alkyl group having 4 to 18 carbon atoms. Tellurium), (meth) acrylic acid cycloalkyl esters (for example, cyclopentyl ester, cyclohexyl ester, etc.), (meth) acrylic acid hydroxyalkyl esters (for example, hydroxyethyl ester, hydroxybutyl ester, hydroxyhexyl ester, etc.), (meta ) Glycidyl acrylate, (meth) acrylic acid, itaconic acid, maleic anhydride, (meth) acrylic acid amide, (meth) acrylic acid N-hydroxymethylamide, (meth) acrylic acid alkylaminoalkyl esters (eg, dimethyl) (Aminoethyl methacrylate, t-butylaminoethyl methacrylate, etc.), vinyl acetate, and (meth) acrylic polymers using one or more of styrene as monomer components.

  The (meth) acrylic polymer is a unit corresponding to another monomer component copolymerizable with the (meth) acrylic acid alkyl ester or cycloalkyl ester, if necessary, for the purpose of modifying cohesive force, adhesiveness and the like. May be included. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride Acid anhydride monomers such as itaconic anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate Hydroxyl group-containing monomers such as 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; The Sulfonic acid groups such as lensulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid Containing monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; acrylamide, acrylonitrile and the like. One or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 30% by weight or less, more preferably 15% by weight or less, based on the total monomer components.

  Furthermore, in order to crosslink the (meth) acrylic polymer, a polyfunctional monomer or the like can be included as a monomer component for copolymerization as necessary. By crosslinking the base polymer, the self-holding property of the pressure-sensitive adhesive layer is improved, so that a large deformation of the pressure-sensitive adhesive sheet can be prevented and the flat state of the pressure-sensitive adhesive sheet can be easily maintained.

  Examples of multifunctional monomers include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and pentaerythritol di (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate, etc. Can be mentioned. These polyfunctional monomers can also be used alone or in combination of two or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

  The (meth) acrylic polymer can be obtained by polymerizing a single monomer or a mixture of two or more monomers. The polymerization can be carried out by any method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, and photopolymerization. In particular, when polymerizing by irradiating radiation such as ultraviolet rays or electron beams, photopolymerization is performed by casting a liquid composition obtained by mixing a monomer component and a photopolymerization initiator in a urethane (meth) acrylate oligomer. It is preferable to synthesize a (meth) acrylic polymer.

  The urethane (meth) acrylate oligomer is a bifunctional compound having a number average molecular weight of about 500 to 100,000, preferably 1000 to 30,000, and having an ester diol as a main skeleton. Examples of the monomer component include morpholine (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and methoxylated cyclodecatriene (meth) acrylate. The mixing ratio of the urethane (meth) acrylate oligomer and the monomer component is preferably oligomer: monomer component = 95-5: 5-95 (% by weight), more preferably 50-70: 50-30 (weight). %). When the content of the urethane (meth) acrylate oligomer is large, the viscosity of the liquid composition tends to be high and polymerization tends to be difficult.

  The pressure-sensitive adhesive layer preferably has a low content of a low molecular weight substance from the viewpoint of preventing contamination of the object to be cut. From this point, the number average molecular weight of the (meth) acrylic polymer is preferably about 200,000 to 3,000,000, more preferably about 250,000 to 1,500,000.

  Moreover, in order to increase the number average molecular weight of the (meth) acrylic polymer as a base polymer, an external cross-linking agent can be appropriately employed for the pressure-sensitive adhesive. Specific means for the external crosslinking method include a method of adding a so-called crosslinking agent such as a polyisocyanate compound, a melamine resin, a urea resin, an epoxy resin, a polyamine, a carboxyl group-containing polymer, and reacting them. When using an external cross-linking agent, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked, and further depending on the intended use as an adhesive. Generally, it is preferable to mix about 1 to 5 parts by weight with respect to 100 parts by weight of the base polymer. Furthermore, you may use additives, such as conventionally well-known various tackifiers and anti-aging agent other than the said component as needed, for an adhesive.

  Moreover, a radiation curable pressure sensitive adhesive can be used as the pressure sensitive adhesive. As the radiation-curable pressure-sensitive adhesive, those having a radiation-curable functional group such as a carbon-carbon double bond and exhibiting adhesiveness can be used without particular limitation. As the radiation curable pressure-sensitive adhesive, an ultraviolet curable pressure-sensitive adhesive whose adhesive strength is reduced by ultraviolet irradiation is desirable. According to the pressure-sensitive adhesive layer, the pressure-sensitive adhesive sheet can be easily peeled off by ultraviolet irradiation after the back grinding (grinding) step or the dicing step.

  Examples of the ultraviolet curable adhesive include, for example, a copolymer (acrylic polymer) of a homopolymer of the (meth) acrylic acid ester or a copolymerizable comonomer and an ultraviolet curable component (carbon-carbon in the side chain of the acrylic polymer). A double bond may be added), a photopolymerization initiator, and, if necessary, conventional additives such as a crosslinking agent, a tackifier, a filler, an anti-aging agent, and a coloring agent. .

  The ultraviolet curable component may be any monomer, oligomer, or polymer that has a carbon-carbon double bond in the molecule and can be cured by radical polymerization. Specifically, for example, urethane oligomer, urethane (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate , Dipentaerystol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexanediol Esters of (meth) acrylic acid and polyhydric alcohols such as di (meth) acrylate and dipentaerythritol hexa (meth) acrylate; ester acrylate oligomers; 2-propenyl di-3 Butenyl cyanurate, 2-hydroxyethyl bis (2-acryloxyethyl) isocyanurate, tris (2-methacryloxyethyl) isocyanurate or isocyanurate compounds such as isocyanurate. In addition, when using the ultraviolet curable polymer which has a carbon-carbon double bond in a polymer side chain as an acrylic polymer, it is not necessary to add the said ultraviolet curable component in particular. The compounding amount of the ultraviolet curable monomer component or oligomer component is, for example, 20 parts by weight to 200 parts by weight, preferably 50 parts by weight with respect to 100 parts by weight of the base polymer such as the (meth) acrylic polymer constituting the pressure-sensitive adhesive. About 150 parts by weight.

  In addition to the additive-type radiation-curable pressure-sensitive adhesive described above, the radiation-curable pressure-sensitive adhesive has a carbon-carbon double bond as a base polymer in the polymer side chain, main chain, or main chain terminal. Intrinsic radiation curable pressure-sensitive adhesives that use materials are listed. The intrinsic radiation curable pressure-sensitive adhesive does not need to contain an oligomer component or the like which is a low molecular component, or does not contain much, so that the oligomer component or the like does not move in the pressure-sensitive adhesive over time. Thereby, the adhesive layer of the stable layer structure can be formed.

  As the base polymer having a carbon-carbon double bond, those having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. As such a base polymer, a polymer having a (meth) acrylic polymer as a basic skeleton is preferable. Examples of the basic skeleton of the (meth) acrylic polymer include the (meth) acrylic polymers exemplified above.

  Introducing a carbon-carbon double bond to the polymer side chain in the (meth) acrylic polymer facilitates molecular design. The method for introducing the carbon-carbon double bond is not particularly limited, and various methods can be adopted. For example, after a monomer having a functional group is previously copolymerized with a (meth) acrylic polymer, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is converted into a radiation of the carbon-carbon double bond. Examples of the method include a condensation or addition reaction while maintaining the curability.

  Examples of combinations of these functional groups include carboxylic acid groups and epoxy groups, carboxylic acid groups and aziridyl groups, hydroxyl groups and isocyanate groups. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable from the viewpoint of easy reaction tracking. In addition, if the combination of these functional groups produces a (meth) acrylic polymer having the carbon-carbon double bond, the functional group is on either side of the (meth) acrylic polymer and the compound. However, in the preferable combination, it is preferable that the (meth) acrylic polymer has a hydroxyl group and the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate, and the like. Examples of the (meth) acrylic polymer include those obtained by copolymerization of the above-exemplified hydroxy group-containing monomers and ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, or diethylene glycol monovinyl ether. It is done.

  As the intrinsic radiation curable pressure-sensitive adhesive, the base polymer (particularly, (meth) acrylic polymer) having the carbon-carbon double bond can be used alone. Further, the radiation-curable monomer component or oligomer component can be blended to such an extent that the characteristics are not deteriorated. The amount of the radiation-curable oligomer component or the like is usually 30 parts by weight or less, preferably 10 parts by weight or less, based on 100 parts by weight of the base polymer.

  The polymerization initiator may be any substance that can be cleaved to generate radicals by irradiation with ultraviolet rays having an appropriate wavelength that can trigger the polymerization reaction. Specifically, for example, benzoin alkyl ethers such as benzoin methyl ether, benzoin isopropyl ether and benzoin isobutyl ether; aromatic ketones such as benzyl, benzoin, benzophenone and α-hydroxycyclohexyl phenyl ketone; benzyldimethyl Aromatic ketals such as ketals; polyvinyl benzophenones; thioxanthones such as chlorothioxanthone, dodecyl thioxanthone, dimethyl thioxanthone, and diethyl thioxanthone. The blending amount of the polymerization initiator is about 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight with respect to 100 parts by weight of the base polymer such as a (meth) acrylic polymer constituting the pressure-sensitive adhesive. Parts by weight.

  On the other hand, examples of the heat-peelable pressure-sensitive adhesive include a heat-foaming pressure-sensitive adhesive in which thermally expandable fine particles are blended with the general pressure-sensitive pressure-sensitive adhesive. After achieving the purpose of bonding the article, heating the pressure-sensitive adhesive containing thermally expandable fine particles causes the pressure-sensitive adhesive layer to foam or expand, changing the surface of the pressure-sensitive adhesive layer into irregularities, and the area of adhesion to the adherend By reducing the adhesive strength, the adhesive strength is reduced so that the articles can be easily separated, and they are used for various purposes such as fixing electronic articles and their materials during processing, and logistics such as transportation.

  There is no particular limitation on the thermally expandable fine particles, and various inorganic and organic thermally expandable microspheres are selected so that they have a combination of different peeling start temperatures, although those with a low peel start temperature and a high peel start temperature. Can be used. The difference between the peeling start temperatures of the two types of thermally expandable microspheres is appropriately determined according to the processing accuracy such as the temperature sensitive characteristics of the thermally expandable microspheres, but is generally 20 ° C to 70 ° C, preferably 30 ° C. The temperature difference is from 50 ° C to 50 ° C.

  The heat-foamable pressure-sensitive adhesive is one that reduces the adhesion area due to foaming of the heat-expandable fine particles due to heat and facilitates peeling, and the heat-expandable fine particles preferably have an average particle diameter of about 1 μm to 25 μm. More preferably, it is 5 μm to 15 μm, and particularly about 10 μm is preferable.

  As the heat-expandable fine particles, a material that expands under heating can be used without particular limitation. However, expandable fine particles obtained by microencapsulating a heat-expandable substance are preferably used from the viewpoint of easy mixing operation. For example, it may be a microsphere in which a substance that easily expands by gasification by heating, such as isobutane, propane, or pentane, is encapsulated in an elastic shell. The shell is usually formed of a thermoplastic material, a hot-melt material, a material that bursts due to thermal expansion, or the like. Examples of the substance forming the shell include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. Thermally expansible microcapsules also have advantages such as excellent dispersibility with the pressure-sensitive adhesive. Examples of commercially available thermal expandable microcapsules include microspheres (manufactured by Matsumoto Yushi Co., Ltd.). In addition, you may add a thermal expansion auxiliary agent as needed.

  The amount of thermally expandable fine particles (thermally expandable microcapsules) to be added to the pressure-sensitive adhesive can be determined as appropriate according to the type of the pressure-sensitive adhesive layer. The amount of the pressure-sensitive adhesive layer containing the conductive fine particles is preferably such that it can maintain 60% or more, preferably 70% or more, more preferably 80% or more of the thickness immediately after thermal expansion. The amount is about 1 to 100 parts by weight, preferably 5 to 40 parts by weight, and more preferably 10 to 20 parts by weight with respect to 100 parts by weight of the base polymer.

  The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 100 μm, more preferably about 5 μm to 50 μm, from the viewpoint of achieving both adhesive fixability and peelability. The adhesive force of the pressure-sensitive adhesive layer is not particularly limited as long as it is within a range that can be finally easily peeled off from the support wafer. For example, the value of 180 degree peel adhesion to the semiconductor wafer is preferably in the range of 1 N / 10 mm to 30 N / 10 mm, and more preferably in the range of 5 N / 10 mm to 20 N / 10 mm.

  The separator is provided as necessary for label processing or for the purpose of smoothing the surface of the pressure-sensitive adhesive layer. Examples of the constituent material of the separator include paper, polyethylene, polypropylene, and synthetic resin films such as polyethylene terephthalate. In order to improve the peelability from the pressure-sensitive adhesive layer, the surface of the separator may be subjected to a peeling treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment as necessary. Further, if necessary, an ultraviolet ray prevention treatment may be performed so that the adhesive sheet does not react with environmental ultraviolet rays. The thickness of the separator is usually about 10 μm to 200 μm, preferably about 25 μm to 100 μm.

  When the pressure-sensitive adhesive layer is made of a radiation curable pressure-sensitive adhesive such as ultraviolet rays, the base material needs to have sufficient radiation transparency in order to irradiate the pressure-sensitive adhesive layer before or after dicing. is there.

  After manufacturing the pressure-sensitive adhesive sheet, when the pressure-sensitive adhesive sheet is once wound up in a roll shape, blocking (fusion between the back surface of the base film (outer layer) and the pressure-sensitive adhesive layer) may be caused. In order to prevent blocking, a layer that suppresses the occurrence of blocking may be provided on the outer side of the outer layer by several μm to several tens of μm. The layer that suppresses the occurrence of blocking is not particularly limited, and examples thereof include a layer subjected to an embossing process. Moreover, you may provide another layer on the opposite side to the side in which the adhesive layer of the base material is provided for the objective similar to the above, or the objective of an expandability improvement.

  The pressure-sensitive adhesive sheet for dicing of an electronic component of the present invention can be used by a generally used method. For example, after affixing and fixing a semiconductor substrate, the semiconductor substrate is cut into element pieces (chips) with a rotating round blade. Then, irradiate ultraviolet rays and / or radiation from the substrate side of the pressure-sensitive adhesive sheet, and then expand (expand) the pressure-sensitive adhesive sheet radially using a dedicated jig, and widen the element piece interval to a constant interval, A method of picking up the element piece by pushing it up with a needle or the like and adsorbing it with an air tweezer or the like, or mounting it at the same time can be mentioned. The electronic component dicing adhesive sheet of the present invention is applied to an adherend such as a semiconductor substrate, a sealing resin substrate in which one or a plurality of chips are individually or integrally sealed with a lead and a sealing resin. Can be used. Further, the attachment surface of the adherend is not limited to a semiconductor, and various materials such as an inorganic material such as metal, plastic, glass, and ceramic can be used. The pressure-sensitive adhesive sheet of the present invention can be used particularly well for materials having a phosphorus compound, a cyanide compound or other reactive groups on the surface.

  EXAMPLES Examples and comparative examples of the pressure-sensitive adhesive sheet for dicing electronic parts of the present invention will be described in detail below, but the present invention is not limited to these.

Example 1
100 parts by weight of a copolymer having a weight average molecular weight of 800,000 (solid content 35%) obtained by copolymerizing 20 parts by weight of methyl acrylate, 10 parts by weight of acrylic acid and 80 parts by weight of 2-ethylhexyl acrylate, polyfunctional acrylate -Based oligomer (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., UV-1700), a terpene phenol resin having a hydroxyl value of 160 KOH mg / g to 170 KOH mg / g as a tackifier (manufactured by Yasuhara Chemical Co., Ltd., YS) Polystar N125) 15 parts by weight, phosphate surfactant as a surfactant (manufactured by Toho Chemical Co., Ltd., Phosphanol RL-210, alkyl group carbon number 18) 0.4 parts by weight (at 50 ° C. A solution in which the solid concentration is dissolved in heated toluene to 2%), and a polyisocyanate compound (as a crosslinking agent) Nippon Polyurethane Industry Co., Ltd., Coronate L) 1 part by weight, 2,2-dimethoxy-2-phenylacetophenone (manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure (registered trademark) 651) as a photopolymerization initiator 3 parts by weight A resin solution serving as a partially-adhesive pressure-sensitive adhesive layer was blended and adjusted, applied to a 38 μm-thick polyester film subjected to silicone release treatment so that the thickness after drying was 20 μm, and dried at 120 ° C. for 5 minutes. Then, the adhesive sheet was produced by laminating | stacking to an acrylic film (The product made from Lon seal industry, ACF-550, thickness 150 micrometers, MFR = 0g / 10min at 120 degreeC, 40% of tearability at 120 degreeC) as a base material.

Example 2
In Example 1, as a substrate, SEBS resin (styrene-butadiene block copolymer hydrogenated product (Kreton Polymer Co., Ltd., MD6945) 70% by weight and acrylic resin (Kuraray Co., Ltd., SA-1000-FR201) 30 The pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 except that a film (thickness 150 μm, MFR at 120 ° C. = 0 g / 10 min, tearability at 120 ° C. = 120%) was used. Produced.

Example 3
In Example 1, as a base material, SEBS resin (styrene-butadiene block copolymer hydrogenated product (Kreton Polymer Co., Ltd., MD6945) 20% by weight and acrylic resin (Kuraray Co., Ltd., SA-1000-FR201) 80 A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, except that a film (thickness 150 μm, MFR at 120 ° C. = 0 g / 10 min, tearability at 120 ° C. 40%) was used. did.

Example 4
In Example 1, as a base material, an acrylic film of layer A (manufactured by Ron Seal Industry Co., Ltd., ACF-550, thickness 50 μm, MFR at 120 ° C. = 0 g / 10 min, tearability at 120 ° C. 40%), A film (thickness 100 μm, MFR at 120 ° C. = 3 g / 10 min, tearability at 120 ° C. = flowing state) using B layer EVA resin (Evaflex P1007, manufactured by Mitsui DuPont Chemical Co., Ltd.) Therefore, a pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 except that a base material having a total thickness of 150 μm bonded with a measurement layer was used and a pressure-sensitive adhesive layer was provided on the A layer.

Comparative Example 1
In Example 1, 150 μm (MFR at 120 ° C. = 3 g / 10 min, tearability at 120 ° C.) produced using EVA resin (Evaflex P1007 manufactured by Mitsui DuPont Chemical Co., Ltd.) as a base material = A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 except that measurement was impossible due to the fluid state.

Comparative Example 2
Example 1 is the same as Example 1 except that a PVC film of 150 μm (Achilles Co., Ltd., Achilles Type C +, MFR at 120 ° C. = 0 g / 10 min, tearability at 120 ° C. 400%) is used as the substrate. A pressure-sensitive adhesive sheet was produced by the same operation.

Comparative Example 3
In Example 1, PET film 150 μm (Lumirror (registered trademark) S10 manufactured by Toray Industries, Inc., MFR = 0 mg / 10 min at 120 ° C., tearability 2% at 120 ° C.) was used as the substrate. A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1.

  The pressure-sensitive adhesive sheets obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were aged at 50 ° C. for 4 days or longer, and then subjected to the following measurements. The results are shown in Table 1.

[Measurement method of MFR]
The MFR of the base material of the present invention indicates a measuring flow rate measured by ASTM D1238. The measurement conditions are shown below.
Measuring device: Melt indexer type II (manufactured by Tester Sangyo Co., Ltd.)
Measurement temperature: 120 ° C
Elution weight: 5kg
Elution diameter: 2.0955mm
Elution port length: 8mm

[Measurement method of tearability of substrate]
The tearability of the base material of the present invention was determined by using, as an index, the elongation when the cut specimen was pulled at a constant tensile speed at the measurement temperature and completely broken. The elongation at break in this case was calculated by the following formula: Breaking length (full length) of test piece / initial length of test piece × 100. It shows that it is easy to tear, so that breaking elongation is small, and it shows that it is hard to tear, so that breaking elongation is large. The measurement conditions are shown below.
Measuring device: Universal tensile testing machine (manufactured by Shimadzu Corporation)
Tensile speed: 50 mm / min
Measurement temperature: 120 ° C
Standing time: The sample was allowed to stand at the measurement temperature for 30 minutes before the measurement.
Specimen size: width 10 mm x length 100 mm x thickness 150 μm
Cut: A 1 mm long cut was made perpendicular to the length direction at the center in the length direction and the end in the width direction of the test piece.

[Dicing conditions]
Using a tape applicator (M-286N, manufactured by Nitto Seiki Co., Ltd.) on the sealing resin surface of the semiconductor package, an adhesive sheet was applied at a speed of 60 mm / sec and a table temperature of 45 ° C. Dicing was performed from the top of the semiconductor package using DFG-651 manufactured by DISCO Corporation. The dicing conditions are shown below.
Blade rotation speed: 38000 rpm
Dicing speed: 100mm / sec
Cutting depth: 70 μm (cutting depth into the substrate)
Blade: Resin blade (manufactured by DISCO Corporation, external shape: 580 mm, blade thickness: 300 μm)
Semiconductor package: LGA package (size 5cm x 5cm x thickness 0.4mm)
Dicing size: 1mm x 1mm
Cutting cooling water amount: 1.5 L / min

[Measurement method of filamentous waste]
All the dicing lines of the diced semiconductor package were observed using an optical microscope, and the number of filaments exposed on the surface of the semiconductor package was measured.

From Table 1, Examples 1 to 3 had an MFR of 0 g / 10 min at 120 ° C. and a tearability at 120 ° C. of 5% to 300%. In Example 4, the substrate has a two-layer structure, the MFR of the substrate on the side in contact with the pressure-sensitive adhesive layer is 0 g / 10 min at 120 ° C., and the tearability at 120 ° C. is 5% to 300%. For this reason, the generation of filamentous waste could be suppressed. On the other hand, in Comparative Example 1, since the MFR at 120 ° C. of the base material was larger than 0 g / 10 min, the base material melted at the time of cutting was cooled and solidified by cooling cutting, and a large amount of filamentous waste was generated. In Comparative Example 2, the MFR at 120 ° C. of the base material was 0 g / 10 min. However, the tearability at 120 ° C. is greater than 300%, and the base material is difficult to tear, so the base material is stretched by the blade. The filamentous waste generated during exposure was exposed on the surface of the semiconductor package without leaving the substrate. In Comparative Example 3, the MFR at 120 ° C. of the base material was 0 g / 10 min. However, the tearability at 120 ° C. was smaller than 5%, and the base material was easily torn. Breaking due to stress, filamentous waste was generated.

Claims (2)

An adhesive sheet for dicing an electronic component used when dicing an electronic component having a wiring board,
Possess an adhesive layer on at least one surface, (meth) MFR is 0 g / 10min at 120 ° C. of the base containing an acrylic resin, wherein the split resistance at 120 ° C. is 5% to 300% An adhesive sheet for dicing electronic components. The base material is composed of at least two layers, and the MFR at 120 ° C. of the base material in contact with the pressure-sensitive adhesive layer for sticking and holding the electronic component is 0 g / 10 min, and tearability at 120 ° C. There dicing adhesive sheet of the electronic component according to 5% to 300% der Ru請 Motomeko 1.