JP5607401B2 - Antistatic type semiconductor processing adhesive tape - Google Patents

Description

  The present invention relates to an adhesive tape for semiconductor processing having antistatic performance, and particularly to a dicing tape having antistatic performance used when producing electrical, electronic and semiconductor parts.

  Conventionally, when producing electrical, electronic parts, and semiconductor parts, adhesive tapes for fixing and protecting parts are used in dicing processes and other processes.

In the semiconductor processing process, the separator is peeled off from the semiconductor processing adhesive tape, the semiconductor wafer to which the adhesive tape is bonded is diced, the cutting powder is washed with ultra-pure water with high electrical insulation, The separated semiconductor chip is picked up. In these steps, static electricity is generated on an adherend such as a substrate (wafer) or a resin-sealed package. When the substrate of a component that forms a circuit is an insulating material such as ceramics or glass, static electricity is not quickly leaked, and there is a case where discharge of the circuit due to a short circuit or adhesion of foreign matters such as dust may occur.
In recent years, high integration of circuits has been accelerated with the thinning of wafers, and it has become a big issue to prevent circuit breakdown due to static electricity. Static eliminators such as ionizers are used to prevent static electricity damage. However, even this does not provide a sufficient antistatic effect, and there is an increasing demand for adhesive tapes for semiconductor processing having antistatic ability. As an adhesive tape for semiconductor processing that has antistatic ability, the base resin film is blended with an antistatic agent, the adhesive layer is blended with an antistatic agent, and charged between the base resin film and the adhesive layer. The introduction of a preventive intermediate layer has been studied.

  In order to impart an antistatic ability to an adhesive tape for semiconductor processing, it is considered effective to provide an antistatic function on the pressure-sensitive adhesive layer side in contact with the adherend. However, when an antistatic agent such as a surfactant or a conductive filler is added to the pressure-sensitive adhesive layer, it is difficult not only to adjust or suppress the physical properties of the pressure-sensitive adhesive and its change with time, but also when the pressure-sensitive adhesive tape is peeled off. Or the antistatic agent may migrate to the adherend and contaminate the adherend. This causes visible glue residue, adherence of microscopic particles, and adhesion of liquids that are not optically observable, and adverse effects such as poor adhesion of parts in subsequent processes. There is a risk.

  On the other hand, by providing an antistatic layer containing a charge transfer boron polymer having a nitrogen atom-boron atom complex structure on one or both surfaces of the base resin film, contamination of the adherend due to the adhesive or physical properties of the adhesive layer A semiconductor fixing pressure-sensitive adhesive tape that is less likely to cause a decrease in reliability due to a change with time or the like is disclosed (for example, see Patent Document 1). Although this adhesive tape can obtain a predetermined antistatic effect, the antistatic performance varies greatly depending on the humidity, and problems remain in the adhesion between the base resin film and the antistatic layer, so an improvement is desired. .

  Also disclosed is a pressure-sensitive adhesive tape for fixing a semiconductor in which an antistatic layer containing a conductive polymer such as polythiophene or polypyrrole is provided on one or both sides of a base resin film (for example, Patent Document 2 and Patent Document 3). reference.). This pressure-sensitive adhesive tape has no change in antistatic performance due to humidity, and is excellent in adhesion between the base resin film and the antistatic layer, contamination of the adherend by the pressure-sensitive adhesive, and change in physical properties of the pressure-sensitive adhesive over time. However, since the antistatic layer is divided by dicing, there is a problem that antistatic performance cannot be maintained after dicing.

  When picking up an adherend such as a semiconductor element or a resin-sealed package from an adhesive tape, it is preferable to reduce the adhesive force of the adhesive layer in contact with the adherend. As a method for that purpose, there is known a method in which a radiation curable adhesive tape containing a radiation curable resin in an adhesive layer is used and radiation irradiation is performed as a pretreatment for pickup. However, since this radiation contains not a little infrared light, the pressure-sensitive adhesive tape is heated by radiation irradiation, and the pressure-sensitive adhesive tape is stretched or partially wrinkled. These elongations and wrinkles not only prevent the adherend from being stored in the carrier cassette used for transfer between processing steps, but also cause variations in the gap between elements in the pick-up process of the adherend, resulting in poor pick-up of the element. It may also cause.

  Some adherends such as semiconductor wafers and resin-encapsulated packages have unevenness on the bonding surface of the adhesive tape, and others have markings (concave portions) generally referred to as laser marks. Since there is a limit to the followability of the pressure sensitive adhesive to the uneven portion, a gap that is not in close contact is interposed between the pressure sensitive adhesive layer and the adherend. Since this gap portion is in contact with air, the radiation curing reaction of the adhesive is inhibited by oxygen in the air. That is, a difference occurs in the degree of radiation curing in the pressure-sensitive adhesive layer. As a result, when picking up, the pressure-sensitive adhesive layer may be peeled off from the base resin film, and adhesive residue may be generated in the concave portion.

JP 2004-189769 A JP 2008-255345 A JP 2008-280520 A

  The present invention provides an adhesive tape for semiconductor processing that exhibits excellent antistatic ability in a semiconductor processing process, has less tape slack due to radiation irradiation, and is less likely to leave an adhesive on an adherend during pick-up. With the goal.

  The present inventors have intensively studied to achieve the above object. As a result, an antistatic layer containing a specific proportion of polypropylene, a styrene elastomer resin, and an antistatic resin containing a polyether, and an adhesive containing a base polymer containing a radiation-curable unsaturated carbon bond in the molecule Adhesive tape containing an adhesive layer exhibits excellent antistatic ability in the semiconductor processing process, and the tape does not loosen even when irradiated with radiation to cure the adhesive layer, and is in contact with the adhesive layer during pick-up It has been found that no adhesive remains on the concave surface of the body. The present invention has been made based on these findings.

That is, the present invention
<1> An antistatic semiconductor processing pressure-sensitive adhesive tape having an antistatic layer on a base resin film and having an adhesive layer on the antistatic layer,
The antistatic layer contains 10 to 45 parts by mass of an antistatic resin containing a polyether with respect to 100 parts by mass of a base resin containing at least 40 to 90% by mass of polypropylene and 60 to 10% by mass of a styrene elastomer resin. A resin composition,
The thickness of the antistatic layer is 60% or more of the total thickness of the base resin film and the antistatic layer;
Wherein the pressure-sensitive adhesive layer on the antistatic layer contains as a base polymer an acrylic copolymer having a radiation-curable unsaturated carbon bond in the molecule, antistatic semiconductor processing adhesive tape,
<2> A copolymer (A1) in which the base polymer contained in the pressure-sensitive adhesive layer comprises a (meth) acrylic acid ester, a hydroxyl group-containing unsaturated compound, a carboxyl group-containing unsaturated compound, and a copolymer ( <1>, which is obtained by addition reaction of a functional group capable of undergoing an addition reaction with respect to the functional group of A1) and a compound (A2) having a radiation-curable unsaturated carbon bond. Antistatic adhesive tape for semiconductor processing,
Is to provide.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesive tape which shows the antistatic ability outstanding in the semiconductor processing process is provided. Moreover, according to this invention, the adhesive tape with few generation | occurrence | production of the slack and wrinkle by the heat | fever which generate | occur | produces at the time of radiation irradiation is provided. Furthermore, according to the present invention, there is provided an adhesive tape in which an adhesive residue (adhesive residue) in an adherend recess is suppressed during pickup.

Hereinafter, the present invention will be described in detail based on preferred embodiments thereof.
The pressure-sensitive adhesive tape for semiconductor processing of the present invention includes at least an antistatic layer and an adhesive layer laminated on the antistatic layer. The pressure-sensitive adhesive tape for semiconductor processing of the present invention usually comprises a base resin film, and an antistatic layer is laminated on the base resin film .

  The antistatic layer contains 10 to 45 parts by mass of an antistatic resin containing a polyether with respect to 100 parts by mass of a base resin containing polypropylene and a styrene elastomer resin. Since the antistatic resin containing a polyether is inferior in heat resistance, if the amount of the polyether in the antistatic layer is too large, the heat resistance of the tape is weakened, and the tape loosens due to heat generated by radiation irradiation or the like. Also, if the amount of polyether in the antistatic layer is too large, the adhesion between the antistatic layer and the pressure-sensitive adhesive layer will be weakened, and delamination will occur between the antistatic layer and the pressure-sensitive adhesive layer when the adherend is picked up. As a result, adhesive residue is generated in the concave portions of the adherend surface layer such as laser marks. On the other hand, if the amount of polyether in the antistatic layer is too small, sufficient antistatic properties cannot be exhibited.

The blending amount of polypropylene in the base resin containing at least polypropylene and styrene elastomer resin is 40 to 90% by mass, and the blending amount of styrene elastomer resin in the base resin is 60 to 10% by mass. In addition, when the said base resin contains another component other than a polypropylene and a styrene-type elastomer resin, the total compounding quantity of the polypropylene in the said base resin, a styrene-type elastomer resin, and the said other component will be 100 mass%. It is blended as follows. The base resin may be made of polypropylene and a styrene elastomer resin. If the amount of polypropylene in the base resin is too large, slack remains after the tape is expanded, and there is a possibility that the adherend may not be stored in the carrier cassette in the same manner as slack due to heat generation. Poor pick-up of the kimono can occur. On the other hand, if the blending amount of polypropylene in the base resin is too small, the heat resistance of the base resin film is weakened, so that the tape loosens due to heat generated during radiation irradiation.
About the styrene-type elastomer resin contained in the said base resin, when there are too many compounding quantities in the said base resin, the heat resistance of a base resin film will weaken and a tape will loosen. Further, if the blending amount of the styrene elastomer resin in the base resin is too small, slack remains after the expansion.

  Examples of the antistatic resin containing polyether used in the present invention include perestat (trade name, manufactured by Sanyo Kasei Kogyo Co., Ltd.), Pebax (trade name, manufactured by Arkema Co., Ltd.), Sanconol (trade name, manufactured by Sanko Chemical Co., Ltd.). ) And the like.

  Examples of the polypropylene used in the present invention include a propylene homopolymer or a random or block copolymer of propylene and a small amount of α-olefin and / or ethylene. In particular, the random copolymer is preferably used because of its good miscibility with antistatic resins including styrene elastomers and polyethers.

  The styrenic elastomer resin used in the present invention is preferably a block copolymer containing a polystyrene block, and preferably exhibits rubber-like elasticity at room temperature. Examples of such resins include styrene / butadiene block copolymer, styrene / isoprene block copolymer, hydrogenated styrene / butadiene block copolymer, hydrogenated styrene / isoprene block copolymer, styrene-ethylene / butylene- Examples thereof include an ethylene block copolymer and a styrene-ethylene / butylene-styrene block copolymer. In particular, hydrogenated styrene / butadiene block copolymers and hydrogenated styrene / isoprene block copolymers are preferably used because of their excellent weather resistance.

In general, in a dicing process using a blade, the tape is cut to about 50% of the tape thickness (total thickness of the antistatic layer and the base resin film) excluding the adhesive layer from the viewpoint of process accuracy and yield. Therefore, in order to ensure a conductive path even after dicing, it is necessary to form the antistatic layer deeper than the cutting depth of the blade. Therefore, when the tape of the present invention includes a base resin film, and the antistatic layer is laminated on the base resin film, the thickness of the antistatic layer is the same as that of the antistatic layer and the base resin film. The total thickness is preferably 60% or more. When the thickness of the antistatic layer is 60% or more of the total thickness of the antistatic layer and the base resin film, there is no possibility that the conductive path is divided after dicing, and sufficient antistatic performance can be obtained. .
If the depth of cut can be ensured, the base resin film may be made of other resins such as polyolefins such as polyethylene, polypropylene and polybutene, ethylene-vinyl acetate copolymers, ethylene- (meth) acrylic acid copolymers and ethylene- Multiple layers with polymer materials such as ethylene copolymers such as (meth) acrylic acid ester copolymers, soft polyvinyl chloride, semi-rigid polyvinyl chloride, polyester, polyurethane, polyamide, polyimide, natural rubber and synthetic rubber A film may be used.

  The antistatic resin forms a streak network inside the resin due to a strong shearing force during film formation, and the streaks serve as a conductive path to release static electricity and exhibit antistatic performance. Therefore, as a film forming method of the substrate containing the antistatic resin, a molding method in which a strong shearing force is applied to the resin at the time of film formation, such as injection molding, extrusion molding, and inflation molding is preferable. On the other hand, in the compression molding method, since the compressive force works, the antistatic resin does not disperse in a streak shape, and in the cast molding, a sufficient shearing force cannot be obtained.

  Since the pressure-sensitive adhesive for the antistatic semiconductor processing pressure-sensitive adhesive tape of the present invention contains a base polymer having a radiation-curable unsaturated carbon bond in the molecule, it has radiation curability. In the present invention, the “base polymer having a radiation-curable unsaturated carbon bond in a molecule” is a polymer having a radiation-curable unsaturated carbon bond introduced in the molecule. A pressure-sensitive adhesive containing a composition in which an oligomer having a radiation-curable unsaturated carbon bond is blended (mixed) with a polymer having no radiation-curable unsaturated carbon bond has a high adhesive force before radiation curing. In order to ensure pick-up property, high radiation curability is required. However, a polymer having high radiation curability has a large cure shrinkage at the time of radiation curing, and due to this cure shrinkage, the pressure-sensitive adhesive tends to bite into the concave portion of the adherend surface layer in contact with the pressure-sensitive adhesive layer such as a laser mark. When the pressure-sensitive adhesive bites into the concave portion of the adherend surface layer, delamination is likely to occur between the base resin film and the pressure-sensitive adhesive layer at the time of pickup, and adhesive residue is likely to occur in the concave portion. Furthermore, when a resin in which polyether is blended in the antistatic layer is applied, the adhesiveness between the base resin film and the pressure-sensitive adhesive layer is lowered, so that adhesive residue is likely to occur. Furthermore, when the heating step is performed, the adhesive bites more into the laser mark, and adhesive residue is more likely to occur in the laser mark.

  As a base polymer having a radiation-curable unsaturated carbon bond in the molecule, a polymer containing an acrylic monomer having at least one radiation-polymerizable carbon-carbon double bond-containing group with respect to the main chain as a constituent unit (Hereinafter referred to as “acrylic copolymer (A)”). The acrylic copolymer (A) has, for example, a carbon chain of a copolymer (A1) comprising a (meth) acrylic acid ester, a hydroxyl group-containing unsaturated compound, a carboxyl group-containing unsaturated compound as a main chain, It can be obtained by addition reaction of a compound (A2) having a functional group capable of undergoing addition reaction with respect to the functional group of the polymer (A1) and a radiation-curable unsaturated carbon bond.

  As said (meth) acrylic acid ester which comprises the said copolymer (A1), C6-C12 hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, decyl acrylate, carbon A pentyl acrylate, n-butyl acrylate, isobutyl acrylate, ethyl acrylate, methyl acrylate, or a methacrylate similar to these may be listed. Since the glass transition temperature of the copolymer decreases as the carbon number of the (meth) acrylic acid ester increases, a copolymer having a desired glass transition temperature can be obtained by using a (meth) acrylic acid ester having a specific carbon number. A polymer can be made. In addition, in order to impart desired properties such as glass transition temperature and compatibility, the above copolymer can be obtained by blending a low molecular compound having an unsaturated carbon bond such as vinyl acetate, styrene, or acrylonitrile. The blending amount of the low molecular weight compound having an unsaturated carbon bond is preferably 5% by mass or less.

  Examples of the hydroxyl group-containing unsaturated compound constituting the copolymer (A1) include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and the like.

  Examples of the carboxyl group-containing unsaturated compound constituting the copolymer (A1) include acrylic acid and methacrylic acid.

  As the “functional group capable of undergoing addition reaction with respect to the functional group of the copolymer (A1)” possessed by the compound (A2), the functional group of the copolymer (A1) is a carboxyl group or a cyclic acid. When it is an anhydrous group, examples include a hydroxyl group, an epoxy group, and an isocyanate group. When the functional group of the copolymer (A1) is a hydroxyl group, examples include a cyclic acid anhydride group and an isocyanate group. In the case where the functional group of the copolymer (A1) is an amino group, an isocyanate group can be exemplified. Specific examples of the compound (A2) include acrylic acid, methacrylic acid, cinnamic acid, itaconic acid, fumaric acid, phthalic acid, 2-hydroxyalkyl acrylates, 2-hydroxyalkyl methacrylates, glycol monoacrylates, glycol monoacrylate. Methacrylates, N-methylolacrylamide, N-methylolmethacrylamide, allyl alcohol, N-alkylaminoethyl acrylates, N-alkylaminoethyl methacrylates, acrylamides, methacrylamides, maleic anhydride, itaconic anhydride, fumaric anhydride Radiation curable with some hydroxyl groups or carboxyl groups of acid, phthalic anhydride, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, polyisocyanate compounds It is possible to enumerate such as those urethanization a monomer having a saturated carbon bonds.

  In the synthesis of the acrylic copolymer (A), examples of the organic solvent in the case where the copolymerization is performed by solution polymerization include ketone-based, ester-based, alcohol-based, and aromatic-based organic solvents, among which toluene, A good solvent for acrylic polymers such as ethyl acetate, isopropyl alcohol, benzene methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, and the like, and preferably a solvent having a boiling point of 60 to 120 ° C. The polymerization initiator is α, α′-azo. A radical generator such as an azobis type such as bisisobutylnitrile or an organic peroxide type such as benzoberperoxide is usually used. At this time, if necessary, a catalyst and a polymerization inhibitor can be used in combination. The polymerization temperature and the polymerization time are adjusted, and then an addition reaction at a functional group is performed, whereby an acrylic copolymer (A ) Can be obtained. In terms of adjusting the molecular weight, it is preferable to use a mercaptan or carbon tetrachloride solvent. The copolymerization is not limited to solution polymerization, and other methods such as bulk polymerization and suspension polymerization may be used.

Furthermore, the acrylic copolymer (A) may be copolymerized with monomers such as acrylonitrile and vinyl acetate for the purpose of controlling adhesiveness and cohesion. The weight average molecular weight of the acrylic copolymer (A) obtained by polymerizing these monomers is preferably 5 × 10 ⁴ to 2 × 10 ⁶ , and preferably 1 × 10 ⁵ to 1 × 10 ^6. Is more preferable.

  The adhesive can further contain a curing agent, whereby the adhesive force and cohesive force can be set to desired values. Examples of such curing agents include polyvalent isocyanate compounds, polyvalent epoxy compounds, polyvalent aziridine compounds, chelate compounds and the like. Specific examples of the polyvalent isocyanate compound include toluylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and those adduct types. Specific examples of the polyvalent epoxy compound include ethylene glycol diglycidyl ether, terephthalic acid diglycidyl ester acrylate, and the like. Specific examples of the polyvalent aziridine compound include tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) -aziridinyl] phosphine oxide, hexa [1 -(2-Methyl) -aziridinyl] triphosphatriazine and the like are used. Specific examples of the chelate compound include ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) and the like.

  The pressure-sensitive adhesive can further contain a radiation polymerization initiator, which makes it possible to polymerize and cure in a short time with a small amount of radiation. Specific examples of such radiation polymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, β-chlore. And anthraquinone. The radiation polymerization initiator is usually blended in an amount of 0.1 to 10 parts by mass with respect to 100 parts by mass of the base polymer.

  The pressure-sensitive adhesive layer of the tape of the present invention has a structure as described above, so that it has a sufficient adhesive force to the adherend before irradiation, and the adhesive force significantly decreases after irradiation. . Therefore, the tape of the present invention can adhere the adherend with sufficient adhesive force before irradiation, and can securely fix the adherend, and can be easily peeled off from the adherend after irradiation. can do. There is no restriction | limiting in particular in the thickness of the adhesive layer in the tape of this invention, Although it can set suitably with the to-be-adhered body to apply, it is preferable that it is 5-30 micrometers.

  As mentioned above, although preferred embodiment of the adhesive tape concerning this invention was described, this invention is not limited to the example which concerns.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to this.
Synthesis Example Synthesis of a base polymer having a radiation-curable unsaturated carbon bond in the molecule A copolymer is obtained by solution radical polymerization using 65 parts by mass of butyl acrylate, 25 parts by mass of 2-hydroxyethyl acrylate, and 10 parts by mass of acrylic acid as raw materials. It was. Next, an acrylic copolymer having a radiation-curable unsaturated carbon bond in the molecule was prepared by allowing 2-isocyanate ethyl methacrylate to drop-react with the copolymer. By adjusting the dropping amount of the 2-isocyanatoethyl methacrylate and the polymerization reaction time, the amount (concentration) of radiation curable unsaturated carbon bonds of the acrylic copolymer was set to 0.5 meq / g.

Preparation Example 1 Preparation of Adhesive Tape for Semiconductor Processing-1
100% by mass of a base resin comprising 70% by mass of random polypropylene (trade name: FW3E manufactured by Nippon Polychem Co., Ltd.) and 30% by mass of hydrogenated styrene-butadiene block copolymer (trade name: manufactured by Dynalon 1320P JSR Co., Ltd.) A resin mixture for forming an antistatic layer was prepared, comprising 15 parts by mass of an antistatic resin (trade name: Pelestat VH230, manufactured by Sanyo Chemical Industries, Ltd.) and a polyether. This was extruded by extrusion film forming on a multilayer base resin film of a random polypropylene layer. The thickness of the antistatic layer was 150 μm, and the ratio of the thickness of the antistatic layer to the total thickness of the base resin film and the antistatic layer was 75%.

  Table 1 shows polyisocyanate compounds (trade name: Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) as a curing agent and α-hydroxycyclohexyl phenyl ketone as a radiation polymerization initiator using the acrylic copolymer prepared in the above synthesis example as a base polymer. The pressure-sensitive adhesive coating liquid A was prepared by blending at the ratio shown in FIG. The above adhesive coating solution was applied at a linear speed of 2 m / min to a polyethylene terephthalate film (thickness 25 μm) that had been subjected to silicon release using a comma coater, and passed through a hot air drying oven set at 110 ° C. to a thickness of 20 μm. An adhesive layer was prepared. This was stuck to the antistatic layer laminated | stacked on said base resin film, and the adhesive tape for antistatic type semiconductor processing with a release film was produced.

Preparation Example 2 Preparation of Adhesive Tape for Semiconductor Processing-2
An antistatic type semiconductor processing pressure-sensitive adhesive tape as in Preparation Example 1, except that the blending amount of the random polypropylene of Preparation Example 1 is 45% by mass and the blending amount of the hydrogenated styrene / butadiene block copolymer is 55% by mass. Was made.

Preparation Example 3 Preparation of adhesive tape for semiconductor processing-3
An adhesive tape for antistatic semiconductor processing was prepared in the same manner as in Preparation Example 1 except that the blending amount of the random polypropylene of Preparation Example 1 was 85% by mass and the blending amount of the hydrogenated styrene / butadiene block copolymer was 15% by mass. Produced.

Preparation Example 4 Preparation of Adhesive Tape for Semiconductor Processing-4
An adhesive tape for antistatic semiconductor processing was produced in the same manner as in Preparation Example 1 except that the adhesive coating liquid A in Preparation Example 1 was replaced with the adhesive coating liquid B having the composition shown in Table 1.

Preparation Example 5 Preparation of adhesive tape for semiconductor processing-5
An adhesive tape for antistatic semiconductor processing was produced in the same manner as in Preparation Example 1 except that the blending amount of the antistatic resin containing the polyether of Preparation Example 1 was 40 parts by mass.

Preparation Example 6 Preparation of adhesive tape for semiconductor processing-6
An antistatic semiconductor processing pressure-sensitive adhesive tape was prepared in the same manner as in Preparation Example 1 except that the thickness of the antistatic layer in Preparation Example 1 was 65% of the total thickness of the base resin film and the antistatic layer.

Reference Example 1 Preparation of adhesive tape for semiconductor processing -7
As in Preparation Example 1, except that the antistatic layer was formed without using the base resin film, and the thickness of the antistatic layer was 100% of the total thickness of the base resin film and the antistatic layer. Thus, an antistatic semiconductor processing pressure-sensitive adhesive tape was produced.

Reference Example 2 Preparation of adhesive tape for semiconductor processing-8
An antistatic semiconductor processing pressure-sensitive adhesive tape was prepared in the same manner as in Preparation Example 1 except that the thickness of the antistatic layer in Preparation Example 1 was 50% of the total thickness of the base resin film and the antistatic layer.

Comparative Example 1 Preparation of adhesive tape for semiconductor processing-9
An antistatic semiconductor processing pressure-sensitive adhesive tape was produced in the same manner as in Preparation Example 1, except that the blending amount of the antistatic resin containing the polyether of Preparation Example 1 was 5 parts by mass.

Comparative Example 2 Preparation of adhesive tape for semiconductor processing-10
An antistatic semiconductor processing pressure-sensitive adhesive tape was produced in the same manner as in Preparation Example 1 except that the blending amount of the antistatic resin containing the polyether in Preparation Example 1 was 50 parts by mass.

Comparative Example 3 Preparation of adhesive tape for semiconductor processing-11
In the same manner as in Preparation Example 1, except that the blending amount of random polypropylene in Preparation Example 1 was 95% by mass and the blending amount of hydrogenated styrene / butadiene block copolymer was 5% by mass, an antistatic semiconductor processing adhesive tape was prepared. Produced.

Comparative Example 4 Preparation of adhesive tape for semiconductor processing-12
In the same manner as in Preparation Example 1 except that the blending amount of random polypropylene in Preparation Example 1 was 35% by mass and the blending amount of hydrogenated styrene / butadiene block copolymer was 65% by mass, an antistatic semiconductor processing adhesive tape was prepared. Produced.

Comparative Example 5 semiconductor processing adhesive tape preparation - 13
In the resin mixture for forming an antistatic layer in Preparation Example 1, instead of 100 parts by mass of a base resin made of random polypropylene and a hydrogenated styrene / butadiene block copolymer, 100 parts by mass of an ionomer resin metal-crosslinked with zinc ions was used. Except for this, an antistatic semiconductor processing adhesive tape was prepared in the same manner as in Preparation Example 1.

About each adhesive tape obtained by the said preparation examples 1-6, reference examples 1-2, and comparative examples 1-5, it is antistatic performance, tape slack after ultraviolet curing, expandability, and a laser mark by the test shown below. The adhesive residue was evaluated.

Test Example 1 Evaluation of antistatic performance A voltage of 500 V was applied using an resistance meter, the current value 60 seconds after reading was read, and the surface of the adhesive surface before dicing (before DC) and after dicing (after DC) The resistivity was measured. Here, “before dicing” means a state before ultraviolet curing, and “after dicing” means a state after ultraviolet curing. Dicing was performed under the conditions shown below, and ultraviolet curing was performed by irradiating with 500 mJ / cm ² ultraviolet rays using a high-pressure mercury lamp. The case where the surface resistivity was less than 1 × 10 ¹³ Ω / □ (ohm / square) was evaluated as “◯”, and the case where the surface resistivity was more than “×” was evaluated. The results are shown in Table 2.

<Dicing conditions>
Dicing machine: DFD-6340 manufactured by DISCO Corporation
Blade: NBC-ZH2050 27HEDD made by DISCO Corporation
Blade rotation speed: 40000 rpm
Cutting speed: 100 mm / s
Cutting water volume: 1.5 L / min
Dicing size: 1mm square Blade height: 65μm

Test Example 2 Evaluation of Tape Looseness after UV Curing The surface having the laser mark of the resin-encapsulated package having the laser mark and the adhesive tape were bonded together and diced under the following conditions. Ultraviolet curing was performed by irradiating with 500 mJ / cm ² of ultraviolet light using a high-pressure mercury lamp, and the appearance of the tape was observed. The case where there was no elongation or sag after UV irradiation was evaluated as “◯”, and the case where new elongation or sag occurred and partial wrinkles occurred was evaluated as “X”. The results are shown in Table 2.

<Dicing conditions>
Dicing machine: DFD-6340 manufactured by DISCO Corporation
Blade: DISCO Corporation B1A801 SD320N100M42
Blade rotation speed: 40000 rpm
Cutting speed: 100 mm / s
Cutting water volume: 1.5 L / min
Dicing size: 2mm square Blade height: 65μm

Test Example 3 Expandability Evaluation Resin-encapsulated package having a laser mark The surface having the laser mark and the adhesive tape are bonded to each other and diced under the same conditions as in Test Example 2, and 500 mJ / cm using a high-pressure mercury lamp. UV curing was performed by irradiating ² UV rays. Thereafter, the tape was expanded 3 mm with a die picker CAP-300II, and the appearance of the tape when the expansion was released was observed. The case where there was no elongation or sag after expansion was evaluated as “◯”, and the case where new elongation or sag occurred and partial wrinkles occurred was evaluated as “X”. Note that tapes that are stretched or slackened by ultraviolet irradiation are indicated as “-” because the tapes are already loosened at the time of expansion and the expandability cannot be evaluated. The results are shown in Table 2.

Test Example 4 Evaluation of Adhesive Residue on Laser Mark The surface of the resin-encapsulated package having the laser mark and the adhesive tape are pasted together and diced under the same conditions as in Test Example 2, using a high-pressure mercury lamp. UV curing was performed by irradiating with 500 mJ / cm ² of UV light. Thereafter, the plate was expanded 5 mm with a die picker CAP-300II, pushed up by 0.5 μm from the bottom of the base resin film, picked up with a vacuum collet, and the laser mark of the resin-sealed package was observed with an optical microscope. The case where there was no adhesive residue on the laser mark was indicated as “◯”, and the case where there was adhesive residue was indicated as “X”. The results are shown in Table 2.

In the tapes of Preparation Examples 1 to 6 included in the adhesive tape of the present invention, the antistatic performance is good before DC and after DC, there is no tape slack after UV curing, and the expandability is excellent. There was no adhesive residue on the laser mark. Also. The tape of Reference Example 2 did not show sufficient antistatic performance after dicing in the test results of this time. The reason for this is considered that the conductive path was divided after dicing because the ratio of the antistatic layer to the thickness of the base resin film and the antistatic layer was small. Since the dicing technique with a shallower notch is put into practical use, the tape of Reference Example 2 is considered to have excellent antistatic ability even after dicing, like the tapes of Preparation Examples 1 to 6 .

Moreover, the tapes of Comparative Examples 1 to 5 were inferior in the evaluation of antistatic performance, tape looseness after UV curing, expandability, or adhesive residue on the laser mark. Since the tape of Comparative Example 1 had a small amount of antistatic agent, the antistatic performance was insufficient.

Claims (2)

An antistatic semiconductor processing pressure-sensitive adhesive tape having an antistatic layer on a base resin film and having an adhesive layer on the antistatic layer,
The antistatic layer contains 10 to 45 parts by mass of an antistatic resin containing a polyether with respect to 100 parts by mass of a base resin containing at least 40 to 90% by mass of polypropylene and 60 to 10% by mass of a styrene elastomer resin. A resin composition,
The thickness of the antistatic layer is 60% or more of the total thickness of the base resin film and the antistatic layer;
Wherein the pressure-sensitive adhesive layer on the antistatic layer contains as a base polymer an acrylic copolymer having a radiation-curable unsaturated carbon bond in the molecule, antistatic semiconductor processing adhesive tape.   The base polymer contained in the pressure-sensitive adhesive layer is a copolymer (A1) composed of (meth) acrylic acid ester, hydroxyl group-containing unsaturated compound, carboxyl group-containing unsaturated compound, and copolymer (A1). The antistatic material according to claim 1, which is obtained by addition reaction of a functional group capable of undergoing an addition reaction with respect to the functional group possessed and a compound (A2) having a radiation-curable unsaturated carbon bond. Type adhesive tape for semiconductor processing.