TWI402325B - Adhesive sheet for dicing and dicing method using the same - Google Patents

Description

Adhesive sheet for cutting and cutting method using the same

The present invention relates to an adhesive sheet for dicing, and more particularly to a method for cutting using the dicing adhesive sheet, and a cut piece obtained by the dicing method.

Conventionally, a semiconductor wafer made of yttrium (Si), gallium (Ga), or arsenic (As) has been manufactured in a large-diameter state, and then cut (separated) into small pieces, and then mounted and packaged. In this package, a plurality of wafers are usually packaged at a time, and the semiconductor package is diced and picked up to form individual semiconductor wafers. The semiconductor package is subjected to a cutting process, a cleaning process, an expansion process, a pick process, and the like while being attached to the adhesive sheet and fixed. The adhesive sheet is usually an adhesive sheet prepared by applying an acrylic adhesive of about 1 to 200 μm on a substrate made of a plastic film.

The cutting process of the semiconductor package is usually performed using a circular blade that moves while rotating. At this time, the circular blade is cut into the inside of the substrate holding the dicing adhesive sheet of the semiconductor package. At this time, if the cutting proceeds to the inside of the base material of the adhesive sheet, the plastic film itself as the base material generates fibrous cutting debris. If the fibrous chips adhere to the side of the package (cut object), etc., the fibrous chips attached to the package are also encapsulated in a subsequent process. As a result, fibrous chips are a cause of a significant deterioration in the quality of the electronic circuit, which is a problem.

The mechanism of the generation of the fibrous swarf is as follows, as described in Japanese Laid-Open Patent Publication No. 2001-72947, when the cutting blade cuts the object to be cut and generates heat by friction, so that the cutting blade is cut into the base film, The resin constituting the base film is melted. The molten resin is rolled up by the rotation of the cutting blade, and is cooled and solidified by the cutting cooling water to become fibrous chips. In the dicing of the ruthenium film which has been conventionally carried out, as described in Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. The generation of fibrous chips is effective, and the reason is presumed to be that the melting point of polypropylene is high and it is rarely melted by the hot cutting blade.

In addition, as a method of solving such a problem of the fibrous chip, in addition to the above-mentioned prior art, a method disclosed in, for example, Japanese Patent Laid-Open No. Hei 5-156214, and Japanese Patent Laid-Open No. Hei 5-211234.

However, in the prior art disclosed in Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. The problem of chipping, but the cutting of the semiconductor package does not eliminate the problem of producing fibrous chips.

In the Japanese Patent Publication No. Hei 11-43656, a base film using an unstretched polypropylene film as an adhesive sheet is proposed. This method can suppress the generation of fibrous chips in the dicing of the crepe, but as a result of research by the inventors of the present application, it has been found that the scission of the semiconductor package has a poor effect of suppressing the solution. Moreover, there is no swelling property, etc., and there are problems in workability.

An adhesive sheet using an ethylene-methacrylate copolymer as a substrate is proposed in Japanese Patent Laid-Open No. Hei 5-156214. However, the adhesive sheet can inhibit the generation of fibrous chips in the enamel cutting, but it cannot satisfy the level required in the manufacture of semiconductor wafers. In addition, in the semiconductor package cutting, it can be said that the effect is almost zero.

An adhesive sheet of a crosslinked film which is irradiated with radiation of an electron beam of 1 to 80 Mrad or γ-rays or the like as a base film is proposed as a base film. When the thickness of the base film of the adhesive sheet is about 80 to 100 μm, it is considered that the dicing sheet has an effect of suppressing the generation of fibrous chips to some extent. However, when the thickness of the base film is 120 μm or more, particularly 150 to 300 μm, fibrous chips are generated when the semiconductor package is cut. This is due to the fact that although the outermost surface of the substrate film is crosslinked to some extent, it is not sufficiently crosslinked by radiation inside the substrate film.

The present invention has been made to solve the above problems in the background art, and an object of the invention is to provide an adhesive sheet for dicing which does not have a disadvantage in product quality and a disadvantage in cost, and which has less fibrous chips during dicing. It is still another object of the present invention to provide a cutting method using the dicing adhesive sheet.

The present inventors conducted intensive studies on a base film constituting a dicing adhesive sheet capable of solving the above problems. As a result, it has been found that the use of a base film having a multilayer structure having a layer containing a vinyl resin and having a melting point of 95 ° C or less can reduce the generation of fibrous chips during dicing, and completed the present invention.

In order to solve the above problems, the dicing adhesive sheet of the present invention is a dicing adhesive sheet having an adhesive layer on at least one surface of a substrate, wherein the substrate has a melting point of 95 ° C or less. A multilayer structure of a layer of a vinyl resin having a thickness of 1/2 or more of the total thickness of the substrate.

When a dicing adhesive sheet having a base material having a high melting point resin (for example, polypropylene or the like) as a main component is used, for example, when the semiconductor package is diced, there is also a frictional heat ratio between the dicing blade and the object to be cut. The case where the melting point is high. Since the semiconductor package has a large thickness compared to the cymbal sheet or the like and the thickness of the dicing blade to be used is large, the friction between the dicing blade and the semiconductor package also becomes large.

In the adhesive sheet for dicing of the present invention, a substrate having a multilayer structure having a layer containing a vinyl resin having a melting point of 95 ° C or less is used as a substrate, and the melt viscosity of the substrate at the time of melting can be sufficiently lowered. Therefore, even if the layer is wound up by the rotation of the dicing blade, it does not cause a state of being stretched into a filament shape due to the melt tension, and it can be scattered like a liquid, and the generation of fibrous chips is remarkably suppressed.

Further, in order to solve the above problems, the dicing adhesive sheet of the present invention is a dicing adhesive sheet having an adhesive layer on at least one surface of a substrate, wherein the substrate has a melting point of 95 ° C or less. A multilayer structure of a layer of a vinyl resin, and the substrate is provided with a layer having a crosslinked structure on a side thereof in contact with the above-mentioned adhesive layer.

When the base material is provided with a layer containing a vinyl resin having a melting point of 95 ° C or less, when the roll is wound up by the rotation of the dicing blade, the melt viscosity of the layer during melting is not sufficiently lowered, and the melt tension is pulled. It is filamentous and thus produces a so-called whisker. This is caused by the fact that the temperature of the cutting blade is lowered due to the fact that the cutting object is no longer present when the cutting blade cuts off the object to be cut. Such a whisker is not directly connected to the object to be cut, but is chopped during cutting, and is sometimes washed by cutting water or the like to be attached to the object to be cut. However, as described above, the portion which is completely cut by the cutting blade is placed on the layer having the crosslinked structure, and the generation of the above-described whisker can be suppressed. In addition, even when the depth at which the cutting blade is cut is large, a layer containing a vinyl resin having a melting point of 95 ° C or less is provided under the layer having the crosslinked structure, so that generation of fibrous chips can be suppressed.

In each of the above configurations, the melt flow rate of the ethylene resin at 190 ° C is preferably 1.5 g/10 min or more.

When the melt flow rate of the above-mentioned ethylene-based resin at 190 ° C is 1.5 g/10 min or more, the fluidity at the time of melting can be increased. As a result, the melt tension can be further lowered, and the resin constituting the above layer can be further suppressed from being stretched into a filament shape.

In each of the above configurations, the total thickness of the base material is preferably 100 μm or more.

The above configuration is such that the adhesive sheet has a sufficient thickness so that the layer thickness of the substrate is 100 μm or more. Thereby, the dicing blade can be sufficiently cut into the adhesive sheet when the semiconductor package is diced. As a result, it is possible to provide an adhesive sheet which can improve the cut grade of the semiconductor package.

In each of the above configurations, the pressure-sensitive adhesive layer preferably comprises a radiation curing adhesive.

When the adhesive layer formed of the radiation-curable adhesive is used, the adhesion can be lowered by irradiation of radiation, and the semiconductor package or the like can be easily peeled off after the semiconductor package or the like is cut and separated.

Moreover, in order to solve the above-mentioned problem, the cutting method of the present invention is a method of cutting a cut material to which the dicing adhesive sheet is bonded, and cutting the base material of the dicing adhesive sheet, and the above-described method is used. The dicing adhesive sheet has an adhesive layer on at least one surface of the substrate, and the substrate has a multilayer structure including a layer of a vinyl resin having a melting point of 95 ° C or less, and the thickness of the layer is 1/2 or more. The total thickness of the material.

According to the above method, even if the layer on the side of the adhesive layer in the substrate is melted by the frictional heat of the cutting blade at the time of cutting, the resin constituting the layer is rolled up by the rotation of the cutting blade due to the melting point of the resin constituting the layer. It is 95 ° C or less and the melt viscosity is sufficiently small, so that the phenomenon that the resin is stretched into a filament shape due to the melt tension is reduced. That is, it scatters like a liquid, so that the generation of fibrous chips can be remarkably suppressed. As a result, for example, the quality of the material to be cut which is encapsulated by the state in which the fibrous chips adhere to the object to be cut is suppressed, and the yield can be improved.

Moreover, in order to solve the above-mentioned problem, the cutting method of the present invention is a method of cutting a cut material to which a cutting adhesive sheet is attached, and cutting the base material of the dicing adhesive sheet, and the above-described method is used. The adhesive sheet for dicing has an adhesive layer on at least one side of a substrate thereof, the substrate being a multilayer structure having a layer containing a vinyl resin having a melting point of 95 ° C or less, and the substrate is adhered thereto The side in contact with the agent layer is provided with a layer having a crosslinked structure.

According to the above method, since the adhesive sheet having the layer having the crosslinked structure on the side where the substrate is in contact with the adhesive layer is used as the adhesive sheet for cutting, even when the cutting blade cuts off the cut object, In the case where the object to be cut is no longer present and the temperature of the cutting blade is lowered, the generation of a so-called whisker can be suppressed. Further, even when the cutting depth of the cutting blade is large, since a layer containing a vinyl resin having a melting point of 95 ° C or less is provided under the layer having the crosslinked structure, the generation of fibrous chips can be suppressed. . As a result, it is possible to suppress a significant decrease in the quality of the material to be cut due to the fact that the chopped whiskers and the fibrous chips are directly attached to the object to be cut in the cutting, thereby improving the yield.

In each of the above methods, the process of picking the cut pieces of the cut piece from the dicing adhesive sheet after the dicing is performed may be further included.

Thereby, the cutting process to the picking process can be performed with the same adhesive sheet, thereby achieving an improvement in production efficiency.

Further, in each of the above methods, the cutting blade used in the above cutting is preferably a diamond blade using metal as a bonding material.

According to the above method, by using metal as a bonding material, it is possible to increase the heat of cutting at the time of cutting. Thereby, the melt viscosity of the resin constituting the layer having a melting point of 95 ° C or less is lowered, and the formation of fibrous chips can be further suppressed.

Further, the cutting method of the present invention is most effective when the above-mentioned object to be cut is a semiconductor package.

According to the above method, since the generation of fibrous chips is reduced, the quality of the semiconductor device is not deteriorated, so that the yield can be improved.

Further, in order to solve the above problems, the cut piece of the present invention is obtained by cutting the object to be cut in the cutting method described above.

The small piece to be cut produced by the cutting method described above does not adhere to fibrous chips and has excellent quality.

The present invention achieves the effects described below by the method described above.

In other words, according to the present invention, by providing a layer containing a vinyl resin having a melting point of 95 ° C or less on the side of the pressure-sensitive adhesive layer, it is possible to reduce the occurrence of fibrous scraps of the substrate which occur at the time of cutting, and it is possible to improve the yield.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

Cutting adhesive sheet

Hereinafter, an adhesive sheet for dicing according to an embodiment of the present invention will be described with reference to the drawings. In the description, unnecessary portions are omitted in the description, and some portions are enlarged or reduced in order to be easily explained. Fig. 1(a) is a schematic cross-sectional view showing the dicing adhesive sheet (hereinafter referred to as an adhesive sheet) of the present embodiment.

As shown in FIG. 1(a), the adhesive sheet 10 has a structure in which an adhesive layer 12 and a separator 13 are laminated in this order on one surface of the base film 11.

The base film (substrate) 11 serves as a support matrix for the adhesive layer 12 or the like, and the base film (substrate) 11 is a multilayer film composed of at least the inner layer 11a and the outer layer 11b. The inner layer 11a is disposed facing the adhesive layer 12.

The inner layer 11a is a layer containing a vinyl resin having a melting point of 95 ° C or less. The melting point of the ethylene-based resin is preferably 40 ° C or higher, and more preferably 70 ° C or higher. This is because if the melting point is too low, it may be difficult to form the inner layer 11a or to store it at room temperature. The vinyl resin is not particularly limited, and examples thereof include an ethylene-vinyl acetate copolymer, an ethylene-(meth)acrylic copolymer, an ethylene-(meth)acrylate copolymer, an ionomer resin, and a polyurethane resin. A polybutadiene resin, a copolymer of ethylene and an α-olefin, and the like. Further, the ethylene-(meth)acrylic acid copolymer means an ethylene-acrylic acid copolymer and/or an ethylene-methacrylic acid copolymer, and the "(meth)" described in the present invention has the same meaning.

The other constituent material included in the inner layer 11a is not particularly limited, and examples thereof include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, SEBS, and SEPS.

The outer layer 11b is not particularly limited, and examples thereof include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, polyester, polyvinyl chloride, ethylene-vinyl acetate copolymer, and ethylene-(methyl). An acrylic copolymer, an ethylene-(meth)acrylate copolymer, an ionomer resin, an ethylene-α-olefin copolymer, and the like.

The content of the above vinyl-based resin is preferably 40% by weight or more, more preferably 50% by weight or more, and particularly preferably 60% by weight or more. By controlling the content of the ethylene-based resin within the above range, the melt viscosity of the inner layer 11a at the time of melting can be sufficiently reduced. As a result, even if the inner layer 11a is wound up by the rotation of the dicing blade, the phenomenon of being stretched into a filament shape due to the melt tension can be prevented.

The ethylene-based resin preferably has a melt flow rate at 190 ° C of 1.5 g/10 min or more, more preferably 2 g/10 min or more. By making the melt flow rate 1.5 g/10 min or more, the fluidity of the inner layer 11a at the time of melting can be improved. Among them, in consideration of the film forming property of the film, the upper limit of the melt flow rate is preferably 12 g/10 min or less.

The thickness of the base film 11 is usually preferably in the range of 100 to 500 μm. However, in order to sufficiently cut the cutting blade into the adhesive sheet 10 at the time of cutting, the adhesive sheet 10 is required to have a sufficient thickness. Therefore, the thickness of the base film 11 is more preferably 120 μm or more. This is to prevent a portion that is insufficiently cut in the object to be cut, and to maintain the cutting quality at a high level.

Here, the thickness of the inner layer 11a is preferably 1/2 or more of the total thickness of the base film 11. In consideration of the thickness of the base film 11, the thickness of the inner layer 11a is in the range of 50 μm or more and less than 250 μm in more detail. Further, the inner layer 11a in the base film 11 must be provided at a position where the cutting blade reaches when the semiconductor package is cut. Therefore, from such a viewpoint, the inner layer 11a is preferably in contact with the adhesive layer 12 and has a thickness of 80 μm or more.

As the base film 11, a film which is not stretched may be used, or a film to which uniaxial or biaxial stretching treatment is applied may be used as needed. Further, on the surface thereof, usual physical or chemical treatment such as matting treatment, corona discharge treatment, primer treatment, and crosslinking treatment (chemical crosslinking (decane bond)) may be performed as needed.

As the adhesive constituting the adhesive layer 12, a pressure-sensitive adhesive which is generally used can be used. Specific examples thereof include various adhesives such as an acrylic adhesive, a rubber adhesive, an anthraquinone adhesive, and a polyvinyl ether. In the case of the adhesion to the semiconductor wafer or the semiconductor package as the object to be cut, the cleaning property when the semiconductor wafer is cleaned with an organic solvent such as ultrapure water or alcohol after peeling, etc., it is preferable to use (meth)acrylic acid. The polymer acts as a (meth)acrylic adhesive for the base polymer.

The (meth)acrylic polymer may, for example, be a (meth)acrylic polymer obtained by using one or two or more of the following compounds as a monomer: (methyl) Alkyl acrylate (such as methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, sec-butyl ester, tert-butyl ester, amyl ester, isoamyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, isodecyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, cetyl An alkyl group having 1 to 30 carbon atoms such as an ester, an octadecyl ester or an eicosyl ester, particularly a linear or branched alkyl ester having 4 to 18 carbon atoms, etc. Cycloalkyl acrylate (eg cyclopentyl ester, cyclohexyl ester, etc.), hydroxyalkyl (meth) acrylate (eg hydroxyethyl ester, hydroxybutyl ester, hydroxyhexyl ester, etc.), (methyl) Glycidyl acrylate, (meth)acrylic acid, itaconic acid, maleic anhydride, decyl (meth) acrylate, N-hydroxymethyl decyl (meth) acrylate, alkyl aminoalkyl (meth) acrylate Ester (eg dimethylaminoethyl methacryl) Ethyl ester, tert-butylaminoethyl methacrylate, etc.), vinyl acetate, styrene.

The (meth)acrylic polymer is modified for cohesive force, adhesion, and the like, and may further contain other monomers corresponding to the above-mentioned (meth)acrylic acid alkyl ester or cycloalkyl ester, if necessary. The unit of the ingredient. Examples of such a monomer component include acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Or a carboxyl group-containing monomer; an anhydride monomer such as maleic anhydride or itaconic anhydride; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, (methyl) ) 4-hydroxybutyl acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, (A) a hydroxyl group-containing monomer such as 12-hydroxydodecyl acrylate or (4-hydroxymethylcyclohexyl)methyl (meth) acrylate; styrene sulfonic acid, allyl sulfonic acid, 2- (Methyl) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamide propylene sulfonic acid, sulfopropyl (meth) acrylate, (meth) propylene decyl naphthalene sulfonic acid, etc. An acid group-containing monomer; a phosphate group-containing monomer such as 2-hydroxyethyl acryloyl phosphate; acrylamide, acrylonitrile, or the like. These copolymerizable monomer components may be used alone or in combination of two or more. The amount of these copolymerizable monomers is preferably 30% by weight (wt%) or less, more preferably 15% by weight or less, based on the total of the monomer components.

In addition, in order to crosslink the (meth)acrylic polymer, a polyfunctional monomer or the like may be contained as a monomer component for copolymerization as needed. By crosslinking the base polymer, the self-retention of the adhesive layer can be improved, and large deformation of the adhesive sheet can be prevented, so that the flat state of the adhesive sheet 10 can be easily maintained.

Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, and neopentyl Diol (meth) acrylate, 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, and the like. These polyfunctional monomers may be used alone or in combination of two or more. The polyfunctional monomer is preferably used in an amount of not less than 30% by weight based on the total of the monomer components, from the viewpoint of adhesion characteristics and the like.

The above (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, or photopolymerization. In particular, when irradiating radiation such as ultraviolet rays or electron beams to carry out polymerization, it is preferred to mix the monomer component and the photopolymerization initiator in a urethane (meth) acrylate oligomer, and thereby obtain the obtained by casting. The liquid composition is photopolymerized to synthesize a (meth)acrylic polymer.

The urethane (meth) acrylate oligomer is an oligomer having a number average molecular weight (Mn) of about 500 to 100,000, preferably 1,000 to 30,000, and is an ester. The diol is a bifunctional compound of the main skeleton. Further, examples of the monomer component include morpholine (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentenyl (methyl). Acrylate, methoxylated cyclotriene (meth) acrylate, and the like. The mixing ratio of the urethane (meth) acrylate oligomer to the monomer component is preferably an oligomer: monomer component = 95 to 5: 5 to 95 (% by weight), more preferably 50 to 70. : 50~30 (wt%). When the content of the urethane (meth) acrylate oligomer is too large, the viscosity of the liquid composition becomes high, and polymerization tends to be difficult.

The adhesive layer 12 preferably has a small content of a low molecular weight substance from the viewpoint of preventing contamination of a cut object or the like. From this, the number average molecular weight of the (meth)acrylic polymer is preferably from about 200,000 to about 3,000,000, more preferably from about 250,000 to about 1,500,000.

Further, in order to increase the number average molecular weight of the (meth)acrylic polymer or the like as the base polymer, an external crosslinking agent may be suitably used in the above-mentioned adhesive. Specific examples of the external crosslinking method include a method in which a reaction is carried out by adding a so-called crosslinking agent such as a polyisocyanate compound, a melamine resin, a urea resin, an epoxy resin, a polyamine or a carboxyl group-containing polymer. When an external crosslinking agent is used, the amount thereof is appropriately determined according to the balance between the amount of the base polymer to be crosslinked and the use as an adhesive. Usually, it is preferable to mix about 1 to 5 parts by weight of the external crosslinking agent with respect to 100 parts by weight of the above base polymer. In addition to the above components, various additives such as tackifiers and antioxidants which are known in the art may be used as needed in the adhesive.

Further, as the above-mentioned adhesive, a radiation-curable adhesive can be used. The radiation-curable adhesive can be used without any particular limitation, and has a radiation-curable functional group such as a carbon-carbon double bond and exhibits adhesiveness. As the radiation-curable adhesive, an ultraviolet-curable adhesive which is irradiated with ultraviolet rays to lower the adhesive force is desired. According to such an adhesive layer 12, peeling of the adhesive sheet 10 can be easily performed by ultraviolet irradiation after the back grinding (polishing) process or after the cutting process.

The ultraviolet curable adhesive may, for example, be a copolymer of the above (meth) acrylate alone or a copolymer of a copolymerizable comonomer (acrylic polymer) or an ultraviolet curable component (may also be in the above acrylic polymer) A material obtained by adding a carbon-carbon double bond to a side chain, a photopolymerization initiator, and a conventional additive such as a crosslinking agent, a tackifier, a filler, an anti-aging agent, and a colorant added as needed.

The ultraviolet curable component may be a monomer, oligomer or polymer having a carbon-carbon double bond in the molecule and curable by radical polymerization. Specific examples thereof include urethane oligomer, urethane (meth) acrylate, tetramethylol methane tetra(meth) acrylate, and trimethylolpropane tri(methyl). Acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol (Meth) of di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc. An ester of acrylic acid and a polyhydric alcohol; an ester acrylate oligomer; 2-propenyl-3--3-butenyl cyanate, 2-hydroxyethyl bis(2-propenyloxyethyl) isocyanate, three (2) Isocyanate or isocyanate compound such as -methacryloxyethyl)isocyanate. Further, when an ultraviolet curable polymer having a carbon-carbon double bond in a polymer side chain is used as the acrylic polymer, it is not necessary to particularly add the above ultraviolet curable component. The amount of the ultraviolet curable monomer component and the oligomer component is, for example, 20 to 200 parts by weight, preferably 50 to 150, per 100 parts by weight of the base polymer of the (meth)acrylic polymer or the like constituting the adhesive. About the weight.

Further, as the radiation-curable adhesive, in addition to the above-described additive type radiation-curable adhesive, it is also possible to use, as a base polymer, a carbon-carbon double on a polymer side chain or in a main chain or at a main chain end. An intrinsic radiation curable adhesive for the base polymer of the bond. Since the intrinsic radiation-curable adhesive does not require an oligomer component or the like containing a low molecular component or is contained in a small amount, there is no phenomenon in which an oligomer component or the like moves in the adhesive over time. Thereby, the adhesive layer 12 of a stable layer structure can be formed.

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

When a carbon-carbon double bond is introduced into the polymer side chain in the above (meth)acrylic polymer, molecular design becomes easier. The method of introducing the carbon-carbon double bond is not particularly limited, and various methods can be employed. The method of introducing the carbon-carbon double bond is exemplified by copolymerizing a (meth)acrylic polymer and a monomer having a functional group in advance, and then having a functional group capable of reacting with the functional group and a carbon-carbon double The compound of the bond undergoes a condensation or addition reaction in a state of maintaining the radiation curability of the carbon-carbon double bond.

Examples of the combination of these functional groups include a carboxylic acid group and an epoxy group, a carboxylic acid group and an aziridine group, a hydroxyl group and an isocyanate group. Among the combinations of these functional groups, a combination of a hydroxyl group and an isocyanate group is preferred from the viewpoint of ease of reaction tracking. Further, if a combination of the above (meth)acrylic polymer having a carbon-carbon double bond is produced by a combination of these functional groups, the functional group may be any one of a (meth)acrylic polymer and the above compound. On the side, in the above preferred combination, it is preferred that the (meth)acrylic polymer has a hydroxyl group, and the above compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryl oxime isocyanate, 2-methyl propylene methoxyethyl isocyanate, m-isopropenyl-α, α-dimethyl benzyl. Isocyanate and the like. In addition, examples of the (meth)acrylic polymer include a hydroxyl group-containing monomer exemplified above, or an ether such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether or diethylene glycol monoethyl ether. A compound obtained by copolymerization of a compound.

As the above-mentioned intrinsic radiation curable adhesive, the above-mentioned base polymer (especially (meth)acrylic polymer) having a carbon-carbon double bond can be used alone. Further, the radiation curable monomer component or oligomer component may be mixed to such an extent that the properties are not deteriorated. The blending 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 a substance which is cleavable to generate a radical by irradiation of ultraviolet rays of a suitable wavelength which is a cause of polymerization reaction. Specific examples thereof include benzoin alkyl ethers such as benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; benzoin, benzoin, benzophenone, and α-hydroxycyclohexyl phenyl ketone; Aromatic ketones; aromatic ketals such as benzyl dimethyl ketal; polyvinyl benzophenone; chlorothioxanthone, dodecyl thioxanthone, dimethyl thioxanthone, diethyl Thiol ketones such as thioxanthone and the like. The amount of the polymerization initiator to be added is about 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, per 100 parts by weight of the base polymer such as the (meth)acrylic polymer constituting the pressure-sensitive adhesive.

On the other hand, as the heat-peelable pressure-sensitive adhesive, a heat-expandable pressure-sensitive adhesive in which the heat-expandable fine particles are mixed with the above-mentioned general pressure-sensitive adhesive is used. After the adhesion of the article is achieved, the adhesive layer 12 is foamed or expanded by heating the pressure-sensitive adhesive containing the heat-expandable particles to make the surface of the adhesive layer 12 uneven, and the adhesion area to the adherend is reduced. In order to reduce the adhesion, it is possible to easily separate the articles, and it can be used for various purposes such as transportation of fixing, transportation, and the like in the processing of electronic articles or materials thereof.

The heat-expandable fine particles are not particularly limited, and various inorganic or organic heat-expandable microspheres can be selected and a combination of a material having a low peeling start temperature and a material having a high peeling start temperature and having a different peeling start temperature can be selected. The peeling start temperature difference of the two types of heat-expandable microspheres is appropriately determined depending on the processing accuracy of the temperature-sensing characteristics of the heat-expandable microspheres, but is generally 20 to 70 ° C, preferably 30 to 50 ° C.

The heat-expandable pressure-sensitive adhesive is an adhesive which reduces the adhesion area by foaming of heat-expandable fine particles by heat and facilitates peeling. The average particle diameter of the heat-expandable fine particles is preferably about 1 to 25 μm, more preferably Fine particles of 5 to 15 μm, particularly preferably about 10 μm.

As the heat-expandable fine particles, a material which expands under heating can be used without particular limitation. However, from the viewpoint of ease of mixing operation and the like, expandable fine particles obtained by microencapsulating a heat-expandable material can be preferably used. For example, it may be a microsphere prepared by encapsulating a substance which is easily vaporized and expanded by heating, such as isobutane, propane or pentane, in an elastic outer casing. The outer casing is usually formed of a thermoplastic substance, a hot meltable substance, a substance which is broken by thermal expansion, or the like. Examples of the material forming the outer shell include a vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, polyfluorene, and the like. . The heat-expandable microcapsules also have an advantage of being excellent in dispersion and mixing property with the above-mentioned adhesive. As a commercial item of a heat-expandable microcapsule, for example, mention is mentioned (trade name; produced by Matsumoto Oil & Fats Co., Ltd.). In addition, a thermal expansion aid may be added as needed.

The amount of the heat-expandable fine particles (heat-expandable microcapsules) to be added to the above-mentioned adhesive can be appropriately determined according to the type of the pressure-sensitive adhesive layer 12 to reduce the adhesion. In general, a preferable mixing amount is such that the thickness of the adhesive layer 12 containing the heat-expandable fine particles can be maintained at 60% or more, preferably 70% or more, more preferably 80% or more of the thickness immediately after the heat-expanded expansion. . Further, the compounding amount is from about 1 to 100 parts by weight, preferably from 5 to 40 parts by weight, more preferably from 10 to 20 parts by weight, per 100 parts by weight of the base polymer.

The thickness of the adhesive layer 12 is preferably from 1 to 100 μm, and more preferably from about 5 to 50 μm, from the viewpoint of achieving both adhesion fixation and peelability. Further, the adhesive force of the adhesive layer 12 is not particularly limited as long as it can be easily peeled off from the support wafer. For example, the value of the 180-degree peeling adhesion to the semiconductor wafer is preferably in the range of 1 to 30 N/10 mm, and more preferably in the range of 5 to 20 N/10 mm.

For the purpose of label processing or smoothing the surface of the adhesive layer 12, the separation layer 13 is provided as needed. The constituent material of the separator 13 may, for example, be a synthetic resin film such as paper, polyethylene, polypropylene or polyethylene terephthalate. In order to improve the peelability from the adhesive layer 12, the surface of the separator 13 may be subjected to a release treatment such as hydrazine treatment, long-chain alkane treatment, or fluorine treatment as needed. Further, if necessary, in order to prevent the adhesive sheet 10 from reacting due to ambient ultraviolet rays, an ultraviolet ray treatment may be applied. The thickness of the separator 13 is usually 10 to 200 μm, preferably 25 to 100 μm.

Further, when the adhesive layer 12 is made of a radiation-curable adhesive such as ultraviolet rays, the base film 11 needs to have sufficient radiation permeability in order to irradiate the adhesive layer 12 with radiation before or after cutting.

The inner layer 11a is a soft layer as compared with a usual substrate or the like. Therefore, after the adhesive sheet 10 is produced, when the adhesive sheet 10 is wound into a roll shape, adhesion may occur (the back surface of the base film 11 (the outer layer 11b) and the adhesive layer 12 are welded together). Therefore, for the purpose of preventing adhesion, a layer of several to several tens of μm for suppressing adhesion may be provided on the outer side of the outer layer 11b. The layer that suppresses the occurrence of adhesion is not particularly limited, and for example, a layer to which an embossing treatment is applied or the like can be exemplified. Further, for the same purpose as described above or for the purpose of improving the expansion performance, another layer may be provided on the side opposite to the side where the adhesive layer 12 is provided on the base film 11.

Next, an adhesive sheet of another embodiment of the present invention will be described. Fig. 1(b) is a schematic cross-sectional view showing the above-mentioned adhesive sheet. The adhesive sheet 10' in Fig. 1(b) is different from the adhesive sheet 10 in that a base film 11' having a layer having a crosslinked structure (hereinafter referred to as a crosslinked layer) 11c is used instead of the base film. 11.

As the crosslinked layer 11c, for example, a polyolefin-based film having a crosslinked structure can be exemplified. The constituent material of the polyolefin-based film is not particularly limited, and examples thereof include polyethylene, polypropylene, polymethylpentene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic copolymer, and ethylene-(methyl). A methyl acrylate copolymer, an ethylene-ethyl (meth) acrylate copolymer, an ethylene-vinyl alcohol copolymer, a polybutene, an ethylene-ionomer copolymer, or the like. These constituent materials may be used alone or in combination of two or more. Further, the crosslinked layer 11c is not limited to a single layer, and may be composed of a plurality of layers.

The thickness of the crosslinked layer 11c is set in consideration of the depth of cut at the time of cutting, and is preferably 20 μm or more and 150 μm or less. Further, in consideration of the change in the crosslinking density in the thickness direction, it is more preferably 20 μm or more and 100 μm or less, and particularly preferably 20 μm or more and less than 40 μm.

In the method of forming the crosslinked layer 11c, the polyolefin film formed of the above-mentioned constituent material is previously irradiated with an electron beam or a gamma ray to be crosslinked, and the film is bonded to the inner layer 11a by dry lamination or the like. In the method, a polyolefin film and another film are formed by a co-extrusion method, and the polyolefin film is crosslinked by irradiation with an electron beam or the like to form a crosslinked layer 11c. The crosslinked layer 11c formed by these methods has a crosslinked structure in which the crosslinking density gradually decreases as it goes away from the irradiation surface in the thickness direction.

The crosslinking density of the crosslinked layer 11c can be controlled by appropriately changing the amount of electron beam or gamma ray irradiation. The amount of electron beam or gamma ray irradiation is usually in the range of 10 to 250 Mrad, preferably 20 to 200 Mrad, and particularly preferably 30 to 150 Mrad. Further, when the crosslinked layer 11c is formed of polyethylene, the amount of electron beam or γ ray irradiation is preferably about 30 to 150 Mrad. Further, when the crosslinked layer 11c is formed of an ethylene copolymer, the amount of electron beam or γ ray irradiation is preferably about 20 to 100 Mrad.

In addition, the so-called electron beam here refers to a free electron beam, that is, a cathode ray. The irradiation of the electron beam is specifically performed by passing the generated electron beam through the polyolefin-based film under predetermined conditions by using an electron beam accelerator (including any type of high energy, low energy, and scanning).

Further, the gamma ray, as generally defined, refers to one of electromagnetic waves emitted when the radioactive element is entangled. setting the irradiation chamber is irradiated with γ-rays having a specific Co ^{6 0-ray} source irradiating a polyolefin-based film and a predetermined amount of a γ-ray is performed. At this time, the polyolefin film can be directly treated in a roll state, and therefore, workability is good.

When the polyolefin film is irradiated with an electron beam or a gamma ray at such an irradiation amount, the occurrence of fibrous chips at the time of cutting can be reduced. Further, the expansion of the adhesive sheet 10' can be performed without any damage without impairing the mechanical properties such as elasticity and strength of the base film 11'. On the other hand, when the amount of electron beam or gamma ray irradiation is less than 1 Mrad, the effect of electron beam or gamma ray irradiation is insufficient, and a large amount of fibrous chips may be generated at the time of dicing as in the case of non-irradiation. In addition, when the amount of electron beam or γ-ray irradiation exceeds 80 Mrad, the mechanical properties such as elasticity and strength of the base film 11' are impaired, and the base film 11' is broken during expansion, and the base after irradiation may be caused. The material film 11' is deteriorated.

Adhesive sheet manufacturing method

Next, a method of manufacturing the adhesive sheet of the present embodiment will be described. In the following description, the case where the adhesive sheet 10 is used is taken as an example.

The base film 11 can be formed by a conventionally known film forming method. Examples of the film forming method include a calender film forming method, a casting method in an organic solvent, an expansion extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method. Law and so on.

Next, a composition containing an adhesive is applied onto the inner layer 11a of the base film 11, and dried (heat-crosslinked as needed) to form an adhesive layer 12. When there are other layers on the inner layer 11a, the adhesive layer 12 is formed on the other layers. Examples of the coating method include roll coating, screen coating, gravure coating, and the like. Further, the coating may be carried out directly on the substrate, or may be applied to a release paper or the like having a surface subjected to a release treatment, and then transferred onto a substrate. Next, the separator 13 is bonded to the surface of the adhesive layer 12, whereby the adhesive sheet 10 of the present embodiment can be obtained.

Cutting method

Next, the cutting method of the present invention will be described by taking a case where the object to be cut is a semiconductor package.

As shown in FIGS. 2(a) to 2(e), the dicing method of the present embodiment includes at least the following processes: a process of bonding the adhesive sheet 10 to the lead frame 14, a mounting process of the semiconductor wafer 15, and bonding with the bonding wires 16. The process of wire bonding, the process of packaging by the sealing resin 17, and the process of cutting the semiconductor package 21 as a packaged structure.

The process of attaching the adhesive sheet 10 to the lead frame 14 is performed by first peeling the separation layer 13 from the adhesive sheet 10 and aligning the positions of the lead frame 14 and the adhesive sheet 10. The bonding can be carried out by a conventionally known method.

As shown in FIG. 2(a) and FIG. 2(b), the wafer pad of the metal lead frame 14 to which the adhesive sheet 10 is bonded is bonded to the outer sheet pad side (the lower side in the drawing). The semiconductor wafer 15 is pasted on the pad 14c.

The lead frame 14 is a frame in which a terminal pattern of QFN is formed by using a metal such as copper as a material, and the electrical connection portion may be covered (plated) with a material such as silver, nickel, palladium or gold. The thickness of the lead frame 14 is generally 100 to 300 μm. Further, a portion which is partially thinned by etching or the like is not in this range.

In order to facilitate the cutting and separation in the subsequent cutting process, the lead frame 14 is preferably an arrangement pattern in which the respective QFNs are neatly arranged. For example, an arrangement pattern or the like arranged in a vertical and horizontal matrix on the lead frame 14 is referred to as a QFN matrix or MAP-QFN, and is one of the most preferable lead frame shapes. In particular, in recent years, in order to increase the number of packages arranged in one lead frame from the viewpoint of productivity, not only these individual packages are finened, but also a plurality of packages can be packaged in one package portion, and the package is greatly expanded. The number of these arrangements.

As shown in FIG. 2(a), in the package pattern region of the lead frame 14, a substrate pattern of QFN in which a plurality of terminal portions 14b are arranged in a plurality of adjacent openings 14a is arranged neatly. In the case of a general QFN, each substrate pattern is composed of a terminal portion 14b having an outer lead surface disposed on the lower side of the opening 14a, a wafer pad 14c disposed at the center of the opening 14a, and a wafer pad at four corners of the opening 14a. A die bar (not shown) of 14c is formed.

The adhesive sheet 10 is adhered to at least the outer side of the package pattern region, and is preferably adhered to the entire periphery including the resin-encapsulated resin package region. The lead frame 14 generally preferably has a guide pin hole for determining the resin package position near the end edge, and is adhered to a region where the guide pin hole is not plugged. Further, since the resin package regions are arranged in plural in the longitudinal direction of the lead frame 14, it is preferable to continuously adhere the adhesive sheets 10 across the plurality of regions.

On the lead frame 14 as described above, a semiconductor wafer 15 which is a wafer/wafer which is a semiconductor integrated circuit portion is mounted. A fixing region called a wafer pad 14c for fixing the semiconductor wafer 15 is provided on the lead frame 14. The adhesion (fixing) of the wafer pad 14c is performed using the conductive paste 19. However, the present invention is not limited to this method, and various methods using an adhesive tape or an adhesive may be employed. When wafer bonding is performed using a conductive paste 19 or a thermosetting adhesive or the like, it is usually cured by heating at a temperature of about 150 to 200 ° C for about 30 to 90 minutes.

The wire bonding process described above is a process in which the tip end of the terminal portion 14b (internal wire) of the lead frame 14 and the electrode pad 15a on the semiconductor wafer 15 are electrically connected by the bonding wires 16 as shown in FIG. 2(c). . As the bonding wire 16, for example, a gold wire or an aluminum wire or the like can be used. The process is generally carried out by heating vibration to 120 to 250 ° C, by using the vibration energy generated by the combined use of ultrasonic waves and the pressure generated by the applied pressure. At this time, the surface of the adhesive sheet 10 adhered to the lead frame 14 by vacuum suction can be reliably fixed to the heating block.

As shown in FIG. 2(d), the above-described packaging process is a process in which the semiconductor wafer side is packaged on one side by the encapsulating resin 17. This process is performed to protect the semiconductor wafer 15 and the bonding leads 16 mounted on the lead frame 14, and is particularly typically molded in a metal mold using an encapsulating resin 17 mainly composed of an epoxy resin. At this time, a metal mold composed of an upper metal mold having a plurality of concave molds and a lower metal mold is usually used, and a plurality of encapsulating resins 17 are simultaneously subjected to a packaging process. Specifically, for example, the heating temperature at the time of resin encapsulation is 170 to 180 ° C, and after curing at this temperature for several minutes, molding is post-cured for several hours. In addition, the adhesive sheet 10 is preferably peeled off before curing after molding.

The above-described dicing process is a process of dividing the semiconductor package 21 into a single semiconductor device by performing full dicing. This cutting is cut to the extent from the cut portion of the encapsulating resin to the inner layer 11a in the base film 11, using, for example, a cutting blade or the like. At this time, the dicing blade generates frictional heat due to friction with the semiconductor package. Thereby, the cutting blade generates heat higher than the melting point of the inner layer 11a. As a result, the inner layer 11a is melted, and the melting point is lower than that of a usual substrate material. Therefore, the resin constituting the inner layer 11a which is rolled up by the cutting blade is not cooled by the cutting cooling water into fibrous chips, but is scattered like a liquid. As a result, the conventional process for inspecting and removing fibrous chips is not required, or the process work can be reduced.

The conditions for cutting can be appropriately set depending on the object to be cut. Among them, the cutting blade must be cut from the surface of the adhesive layer 12 to a position of 70 μm or more. This is because the inner layer 11a in the base film 11 is placed at this position. In addition, the temperature of the cutting cooling water is usually in the range of 10 to 30 °C.

Here, as shown in (a) and (b) of FIG. 3, as the dicing blade, it is preferable to use a bonding material 33 having a metal such as a nickel alloy and a sandpaper-like dispersion in the bonding material 33 to be held by each. A plurality of diamond particles 32 (2 to 6 μm) of diamond blades 31. When the cutting is performed using the diamond blade 31, since the bonding material 33 is composed of metal, the friction heat generated by the cutting particularly becomes large. As a result, the melt viscosity of the inner layer 11a can be further lowered, and the suppression of the formation of fibrous chips is effective.

Further, in the present invention, a process of picking up a semiconductor element as a small piece to be cut from the dicing adhesive sheet 10 after dicing may be included. The method of picking up is not particularly limited, and various conventionally known methods can be employed. For example, a method in which each semiconductor element is protruded from the adhesive sheet 10 side (lower side) by a needle, and a protruding semiconductor element is picked up by a pick-up device can be mentioned.

Further, in the present embodiment, the semiconductor package 21 is described as an example of the object to be cut, but the present invention is not limited thereto. As the object to be cut, a ruthenium sheet, a compound semiconductor wafer, glass, or the like can be exemplified in addition to the semiconductor package 21. Further, when these cut objects are used, the bonding to the adhesive sheet 10 can be carried out by a conventionally known method.

Hereinafter, preferred embodiments of the present invention will be described in detail. In addition, the material, the mixing amount, and the like described in the examples are not intended to limit the scope of the invention, and the description is merely illustrative.

Example 1

First, 95 parts by weight of butyl acrylate and 5 parts by weight of acrylic acid were copolymerized in ethyl acetate by a conventional method. Into a solution containing the obtained acrylic copolymer (number average molecular weight: 800,000), 70 parts by weight of dipentaerythritol hexaacrylate (trade name " DPHA", manufactured by Nippon Kayaku Co., Ltd.), 3 parts by weight of a radical polymerization initiator (trade name " 651", . . Production), 5 parts by weight of polyisocyanate compound (trade name " L", Japan Production), preparing an acrylic UV-curable adhesive solution. This solution was applied to the anthrone treatment surface of a polyester separator (separation layer), and the solution was heated and crosslinked by heating at 800 ° C for 10 minutes. Thus, an ultraviolet curable adhesive layer (adhesive layer) having a thickness of 20 μm was formed.

Next, a base film (substrate) was produced. Namely, ethylene-vinyl acetate copolymer (EVA) resin (melting point 84 ° C, melt flow rate 2.5 g/10 min) and low density polyethylene (LDPE) resin (melting point 110 ° C, melt flow rate 2.3 g/10 min) The film was formed by a T-die coextrusion method, and the EVA layer (inner layer) / LDPE layer (outer layer) = 120 μm / 30 μm. A corona treatment is further applied to one side of the EVA layer. In addition, the melt flow rate was measured in accordance with JIS K7210. Further, the measurement conditions were a test temperature of 190 ° C and a load of 21.18 N.

Next, the adhesive layer provided on the polyester release layer and the corona-treated surface of the base film are bonded to each other. Thus, the ultraviolet curable semiconductor package dicing adhesive sheet of the first embodiment was produced.

Example 2

First, in the same manner as in Example 1, an ultraviolet curable adhesive layer was formed on the polyester separator. Next, an ethylene-ethyl acrylate copolymer (EEA) resin (melting point 92 ° C, melt flow rate 5 g/10 min) and low density polyethylene (LDPE) resin (melting point 110 ° C, melt flow rate 3.5 g/10 min) 'The film was formed by a T-die co-extrusion method, and the EEA layer (inner layer) / LDPE layer (outer layer) = 150 μm / 50 μm. Further, a corona treatment was applied to one side of the EEA layer to prepare a substrate film. Next, the adhesive layer provided on the polyester release layer and the corona-treated surface of the base film are bonded to each other. Thus, the ultraviolet curable semiconductor package dicing adhesive sheet of the second embodiment was produced.

Example 3

In the same manner as in Example 1, an ultraviolet curable adhesive layer was formed on the polyester separator. Next, low density polyethylene (LDPE) resin (melting point 110 ° C, melt flow rate 2 g/10 min) and ethylene-vinyl acetate copolymer (EVA) resin (melting point 84 ° C, melt flow rate 2.5 g/10 min) The film was formed by a T-die coextrusion method, and the LDPE layer/EVA layer (inner layer) / LDPE layer (outer layer) = 70 μm / 100 μm / 30 μm. Further, an EBE layer having a thickness of 70 μm was irradiated with an electron beam to crosslink it to prepare a base film (* irradiation conditions: an irradiation amount of 100 Mrad). Next, the adhesive layer provided on the polyester separator and the LDPE layer having a thickness of 70 μm were brought into face-to-face contact. Thus, the ultraviolet curable semiconductor package dicing adhesive sheet of the third embodiment was produced.

Comparative Example 1

As a base film, a low-density polyethylene (LDPE) resin (melting point: 110 ° C, melt flow rate: 2 g/10 min) was used to form a substrate film having a thickness of 150 μm by a T-die extrusion method, and on one side thereof. An ultraviolet curable semiconductor package dicing adhesive sheet was obtained in the same manner as in the above-described Example 1 except that the corona treatment was applied.

Comparative Example 2

As a base film, an EVA resin (melting point: 103 ° C, melt flow rate: 2 g/10 min) was formed by a T-die extrusion method while forming a film having a thickness of 200 μm while applying a matting treatment, and the opposite of the matte treatment. In the same manner as in the above-described Example 1, except that a corona treatment was applied to the surface, an ultraviolet curable semiconductor package dicing adhesive sheet was obtained.

Comparative Example 3

As a base film, a low-density polyethylene (LDPE) resin (melting point: 110 ° C, melt flow rate: 2 g/10 min) was formed by a T-die extrusion method to form a film having a thickness of 200 μm, and one side was irradiated with an electron beam ( * Irradiation conditions are 100 Mrad). An ultraviolet curable semiconductor package dicing adhesive sheet was obtained in the same manner as in Example 1 except that the base film obtained in this manner was used.

Evaluation test

Each of the dicing adhesive sheets produced in each of the examples and the comparative examples was evaluated by the following method. Specifically, a 10 cm × 10 cm epoxy substrate having a thickness of 1.0 mm was attached to the dicing adhesive sheet, and dicing was performed under the following conditions.

Cutting conditions: Cutting machine: DDF-651 cutting blade produced by DISCO: BIA801DC320N50M51 cutting blade produced by DISCO: Number of revolutions: 45000 rpm Cutting speed: 50 mm/sec Cutting depth: 100 μm from the surface of the adhesive sheet Cutting size: 5×5 mm cutting mode : Cut down

The cutting line cut by the cutting test was observed with an optical microscope (100 times), and the number of fibrous chips on the portion of the epoxy substrate and the portion where the epoxy substrate was not present on the adhesive sheet was counted. The results are shown in Table 1 below. As can be seen from Table 1, the generation of fibrous chips in the adhesive sheets of Examples 1 to 3 was small, and the fibrous chips generated when the substrate having a size of 10 cm × 10 cm was cut into 5 × 5 mm was 30 or less. level. On the other hand, in the adhesive sheets of Comparative Examples 1 and 2, the generation of fibrous chips was extremely large, and the practical level was not obtained.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

10, 10’. . . Adhesive film

11, 11’. . . Substrate film (substrate)

11a. . . Inner layer

11b. . . Outer layer

11c. . . Crosslinked layer

12. . . Adhesive layer

13. . . Isolation layer

14. . . Lead frame

14a. . . Opening

14b. . . Terminal part

14c. . . Wafer pad

15. . . Semiconductor wafer

15a. . . Electrode pad

16. . . Bonding lead

17. . . Encapsulation resin

19. . . Conductive paste

twenty one. . . Semiconductor package

31. . . Diamond blade

32. . . Diamond particle

33. . . Bonding material

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a dicing adhesive sheet of the present invention, wherein (a) shows a case where a base film is composed of an inner layer and an outer layer, and (b) shows a substrate film having a layer for preventing movement. Happening.

Fig. 2 is a schematic cross-sectional view showing an adhesive sheet for dicing according to an embodiment of the present invention.

Fig. 3 is a schematic view for explaining a cutting blade of one embodiment of the present invention, wherein a sub-figure (a) shows a cutting blade, and a sub-figure (b) shows a main portion of the cutting blade.

10. . . Adhesive film

11. . . Substrate film (substrate)

11a. . . Inner layer

11b. . . Outer layer

12. . . Adhesive layer

13. . . Isolation layer

Claims (17)

An adhesive sheet for dicing, characterized in that an adhesive layer is provided on at least one side of a substrate, and the substrate is a multilayer structure having a vinyl resin having a melting point of 95 ° C or lower. a layer having a thickness of 1/2 or more of a total thickness of the substrate, a melt flow rate of the vinyl resin at 190 ° C of 1.5 g/10 min or more, and a melting point of 95 ° C or less The layer of the vinyl resin faces the adhesive layer. The adhesive sheet for dicing according to claim 1, wherein the total thickness of the substrate is 100 μm or more. The adhesive sheet for dicing according to claim 1, wherein the adhesive layer is composed of a radiation curable adhesive. An adhesive sheet for dicing, characterized in that an adhesive layer is provided on at least one side of a substrate, and the substrate is a multilayer structure having a layer containing a vinyl resin having a melting point of 95 ° C or lower. And the substrate is provided with a layer having a crosslinked structure on a side thereof in contact with the adhesive layer. The adhesive sheet for cutting according to claim 4, wherein the ethylene resin has a melt flow rate at 190 ° C of 1.5 g/10 min or more. The adhesive sheet for dicing according to claim 4, wherein the total thickness of the substrate is 100 μm or more. The adhesive sheet for dicing according to claim 4, wherein the adhesive layer is composed of a radiation curable adhesive. A cutting method for cutting by cutting a cut object to which a cutting adhesive sheet is attached, to a base material of the cutting adhesive sheet, the cutting adhesive sheet having adhesion on at least one side of a substrate thereof The agent layer is a multilayer structure having a layer containing a vinyl resin having a melting point of 95 ° C or less, and the thickness of the layer is 1/2 or more of the total thickness of the substrate. The cutting method according to claim 8, characterized in that the method comprises the following steps: after the cutting, the cut piece of the cut piece is picked up from the adhesive sheet for cutting. A cutting method according to the invention of claim 8, characterized in that, as the cutting blade used in the cutting, a diamond blade using metal as a bonding material is used. The cutting method according to claim 8, wherein the object to be cut is a semiconductor package. A cut piece of a cut piece obtained by cutting the cut object in the cutting method according to item 8 of the patent application. A cutting method for cutting by cutting a cut object to which a cutting adhesive sheet is attached to a base material of the cutting adhesive sheet, wherein the cutting adhesive sheet has adhesiveness on at least one side of a substrate thereof a substrate having a multilayer structure having a layer containing a vinyl resin having a melting point of 95 ° C or less, and the substrate having crosslinks on a side thereof in contact with the adhesive layer The layer of the structure. The cutting method according to claim 13, which comprises the following process: after performing the cutting, from the cutting adhesive The piece picks up the cut piece of the cut piece. A cutting method according to claim 13, characterized in that as the cutting blade used in the cutting, a diamond blade using metal as a bonding material is used. The cutting method according to claim 13, wherein the object to be cut is a semiconductor package. A small piece to be cut which is obtained by cutting the cut object in the cutting method according to item 13 of the patent application.