JP5865045B2 - Dicing sheet with protective film forming layer and chip manufacturing method - Google Patents

Description

  The present invention relates to a dicing sheet with a protective film forming layer that can form a protective film on the back surface of the chip and can improve the manufacturing efficiency of the chip. Moreover, this invention relates to the manufacturing method of the chip | tip using the dicing sheet with a protective film formation layer.

  2. Description of the Related Art In recent years, semiconductor devices have been manufactured using a so-called “face down” mounting method. In the face-down method, a semiconductor chip (hereinafter simply referred to as “chip”) having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate. For this reason, the surface (chip back surface) opposite to the circuit surface of the chip may be exposed.

  The exposed back surface of the chip may be protected by an organic film. Conventionally, a chip having a protective film made of an organic film is obtained by applying a liquid resin to the back surface of a wafer by spin coating, drying and curing, and cutting the protective film together with the wafer. However, since the thickness accuracy of the protective film formed in this way is not sufficient, the product yield may be lowered.

  In order to solve the above problems, a chip protective film having a release sheet and a protective film forming layer formed on the release sheet and composed of an energy ray-curable component and a binder polymer component is disclosed (Patent Document). 1).

  Furthermore, at the present time when semiconductor chips are becoming thinner and denser, even when exposed to severe temperature conditions, a semiconductor device mounted with a chip with a protective film has higher reliability. Is required.

JP 2009-138026 A

  According to the study by the present inventors, the chip protective film described in Patent Document 1 may shrink when the protective film forming layer is cured, which may cause a problem that the semiconductor wafer is warped. In particular, the above problem is remarkable in an extremely thin semiconductor wafer. If the semiconductor wafer is warped, the wafer may be damaged or the marking (printing) accuracy on the protective film may be reduced. Moreover, in the protective film for chips described in Patent Document 1, when manufacturing a chip with a protective film, it is necessary to affix the wafer with a protective film on the dicing sheet, and the manufacturing process is complicated. In addition, when the protective film forming layer is cured by heating, depending on the base material of the dicing tape, residual stress due to heat is generated on the base material, which may adversely affect subsequent processes.

  The present invention has been made in view of the above circumstances. That is, an object of the present invention is to provide a dicing sheet with a protective film forming layer that can easily manufacture a semiconductor chip having a protective film with high uniformity of thickness and excellent printing accuracy, and has heat resistance. To do.

The present invention includes the following gist.
[1] A base film that has been subjected to a peeling treatment, a protective film forming layer formed on the inner peripheral portion of the base film, and an adhesive layer formed on the outer peripheral portion of the base film,
The melting point of the base film exceeds 130 ° C. or does not have a melting point,
A dicing sheet with a protective film forming layer, wherein the base film has a thermal shrinkage of −1 to + 1% when heated at 130 ° C. for 2 hours.

[2] The dicing sheet with a protective film forming layer according to [1], wherein the protective film forming layer is thermosetting.

[3] The dicing sheet with a protective film forming layer according to [1] or [2], wherein the total light transmittance of the substrate film at a wavelength of 532 nm and a wavelength of 1064 nm is 70% or more.

[4] The dicing sheet with a protective film forming layer according to any one of [1] to [3], wherein the protective film forming layer contains a binder polymer component (A) and a curable component (B).

[5] The protective film forming layer contains a colorant (C),
The dicing sheet with a protective film forming layer according to any one of [1] to [4], wherein the maximum transmittance of the protective film forming layer at a wavelength of 300 to 1200 nm is 20% or less.

[6] The protective film forming layer of the protective film forming layer-attached dicing sheet according to any one of [1] to [5] is attached to a workpiece, and the following steps (1) to (3) are performed as (1): , (2), (3) in order of chip manufacturing method;
Step (1): The protective film forming layer is cured to obtain a protective film.
Step (2): Dicing workpiece and protective film,
Step (3): The protective film and the base film are peeled off.

[7] The method for manufacturing a chip according to [6], wherein the following step (4) is further performed after the step (1);
Step (4): Laser printing on the protective film.

  When the protective film is formed on the back surface of the semiconductor chip, the dicing sheet with the protective film forming layer according to the present invention can be used for heat curing with the dicing sheet attached to the semiconductor wafer. Thus, a protective film having high uniformity and excellent printing accuracy can be easily formed.

Sectional drawing of the dicing sheet with a protective film formation layer concerning this invention is shown.

  Hereinafter, the present invention will be described more specifically, including its best mode. As shown in FIG. 1, the dicing sheet 10 with a protective film forming layer according to the present invention includes a base film 1 that has been subjected to a peeling treatment, a protective film forming layer 4 that is formed on the inner periphery of the base film 1, The adhesive layer 2 is formed on the outer peripheral portion of the base film 1, and is attached to the ring frame 5 through the adhesive layer 2 at the outer peripheral portion of the base film 1.

(Base film)
The base film in the present invention has been subjected to a release treatment. Specifically, the entire surface of the base film or the inner peripheral portion of the base film (the surface on which the protective film forming layer is formed) is subjected to a release treatment.

  As the release agent used for the release treatment, alkyd, silicone, fluorine, unsaturated polyester, polyolefin, wax, and the like are used. In particular, alkyd, silicone, and fluorine release agents are heat resistant. This is preferable.

  In order to release the surface of the base film using the above release agent, the release agent can be used without any solvent, or can be diluted or emulsified with a solvent, and can be used with a gravure coater, Mayer bar coater, air knife coater, roll coater, etc. The laminate may be formed by coating at room temperature, heat curing, or electron beam curing, wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, or the like.

  Further, the base film has heat resistance. Specifically, the base film has a melting point of 130 ° C. or no melting point, and the base film has a heat shrinkage rate when heated at 130 ° C. for 2 hours. Is −1 to + 1%. If the melting point of the base film is 130 ° C. or lower or the thermal shrinkage rate is out of the above range, the base film is melted when the protective film forming layer is cured, and it becomes difficult to maintain the shape of the base film. There is a risk that subsequent processes cannot be performed. In addition, the base film may be fused with peripheral devices in the semiconductor chip manufacturing process. Furthermore, the printing accuracy on the protective film may decrease due to the deformation of the protective film forming layer caused by the melting of the base film. The thermal contraction rate is an index indicating the ease of thermal deformation of the base film. When a dicing sheet with a protective film forming layer is formed from a base film having a thermal shrinkage rate of less than -1% or more than + 1%, and the wafer is held and thermally cured, the shrinkage of the base film occurs. The remaining stress is released in a later dicing process, and the distance between the chips may be reduced. Such narrowing of the chip interval hinders picking up of the chip from the dicing sheet (pickup), may deteriorate the alignment of the chip, and may cause chipping due to contact with the adjacent chip. . When the thermal contraction rate of the base material is −1 to + 1%, such a narrowing of the chip interval can be prevented.

  The base film preferably has a melting point of 140 ° C. or higher or no melting point, more preferably a melting point of 200 ° C. or higher or no melting point. Note that “having no melting point” means that the melting point is higher than the combustion temperature of the resin. By making the melting point and heat shrinkability of the base film within the above ranges, the heat resistance of the base film is excellent, and the shape retention of the base film when the above protective film forming layer is cured is kept better. It is easy to obtain the effect of preventing the above-mentioned narrowing of the chip interval. In addition, the thermal contraction rate of the base film at the time of heating at 130 ° C. for 2 hours is obtained from the area of the base film before and after the base film is put in an environment at 130 ° C. by the following formula.

  Thermal shrinkage (%) = {(Area of base film before input) − (Area of base film after input)} / Area of base film before input × 100

  Examples of the base film include polypropylene, polybutylene terephthalate, annealed polyester film, polycarbonate film, polyphenylene sulfide film, cycloolefin resin film, polyimide resin film, and a laminate of two or more of these. it can. These may be uniaxially stretched or biaxially stretched. A base film is not specifically limited as long as the said physical property is satisfy | filled.

  The base film in the present invention has been subjected to a release treatment. Specifically, the entire surface of the base film or the inner peripheral portion of the base film (the surface on which the protective film forming layer is formed) is subjected to a release treatment.

  When a polyolefin-based film such as a polypropylene film is used as the substrate, the protective film forming layer may be peeled from the substrate film without performing a peeling treatment depending on the characteristics of the film. In such a case, a base film that has not been peeled may be used.

  The thickness of a base film is not specifically limited, Preferably it is 30-300 micrometers, More preferably, it is 50-200 micrometers. By setting the thickness of the base film within the above range, the dicing sheet with a protective film-forming layer has sufficient flexibility, and thus exhibits good adhesiveness to a workpiece (for example, a semiconductor wafer).

  The total light transmittance of the base film at a wavelength of 532 nm and a wavelength of 1064 nm is preferably 70% or more, more preferably 75% or more. By making the total light transmittance of the base film at a wavelength of 532 nm and a wavelength of 1064 nm within the above range, it is possible to perform laser marking over the base film after affixing a dicing sheet with a protective film forming layer to a semiconductor wafer. Become.

  The base film may be provided with a plurality of fine through holes in a region where the protective film forming layer is provided. By providing the through hole, it is possible to suppress the generation of foreign matters caused by the gas generated when laser marking is performed on the protective film forming layer.

(Adhesive layer)
The pressure-sensitive adhesive layer in the present invention can be formed of various known pressure-sensitive adhesives. Such an adhesive is not limited at all, but an adhesive such as rubber-based, acrylic-based, silicone-based, or polyvinyl ether is used. In addition, an energy ray curable adhesive, a heat-foaming adhesive, or a water swelling adhesive can be used. As the energy ray curable (ultraviolet ray curable, electron beam curable) pressure-sensitive adhesive, it is particularly preferable to use an ultraviolet curable pressure-sensitive adhesive.

  The pressure-sensitive adhesive layer is formed on the outer peripheral portion of the base film, and is affixed to the ring frame at the outer peripheral portion of the base film when manufacturing a chip to be described later. If the pressure-sensitive adhesive layer is attached to the ring frame and the protective film forming layer is cured, adhesive residue may be generated on the ring frame when the ring frame is removed from the pressure-sensitive adhesive layer. Further, in the curing step of the protective film forming layer, the pressure-sensitive adhesive layer is exposed to a high temperature and softens, and adhesive residue is likely to occur. Therefore, among the above-mentioned pressure-sensitive adhesives, acrylic and silicone pressure-sensitive adhesives are preferable from the viewpoint of preventing adhesive residue on the ring frame and imparting heat resistance to the pressure-sensitive adhesive layer. Further, when the entire surface of the base film is peeled using a silicone-based release agent, a silicone-based pressure-sensitive adhesive is preferably used from the viewpoint of adhesiveness between the base film and the pressure-sensitive adhesive layer.

  Further, the adhesive strength of the pressure-sensitive adhesive layer applied to the ring frame (adhesive strength to the SUS plate after being applied and heated at 130 ° C. for 2 hours) is preferably 15 N / 25 mm or less, more preferably 10 N / 25 mm or less, particularly preferably 5 N / 25 mm or less. By setting the adhesive strength of the pressure-sensitive adhesive layer within the above range, the adhesiveness to the ring frame is excellent, and adhesive residue on the ring frame can be prevented.

  Although the thickness of an adhesive layer is not specifically limited, Preferably it is 1-100 micrometers, More preferably, it is 2-80 micrometers, Most preferably, it is 3-50 micrometers.

  Moreover, the adhesive layer may consist of the double-sided tape which provided the adhesive layer on both surfaces of the core film. The double-sided tape has a configuration of pressure-sensitive adhesive layer / core film / pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer in the double-sided tape is not particularly limited, and the above-mentioned pressure-sensitive adhesive can be used. In this case, it is preferable to use a silicone-based pressure-sensitive adhesive as the pressure-sensitive adhesive layer in contact with the base film from the viewpoint of adhesiveness between the base film and the pressure-sensitive adhesive layer. The core material film preferably has heat resistance, and it is preferable to use a film having a melting point of 120 ° C. or higher as the core material film. When a film having a melting point of less than 120 ° C. is used as the core material film, the core material film may be melted and unable to maintain its shape or may be fused with peripheral devices during the heat curing of the protective film forming layer. is there. As the core material film, for example, a polyester film, a polypropylene film, a polycarbonate film, a polyimide film, a fluororesin film, a liquid crystal polymer film and the like are preferably used.

(Protective film forming layer)
The protective film forming layer in the present invention is not particularly limited, and for example, a thermosetting, thermoplastic, or energy ray curable protective film forming layer can be used. Among these, the above-mentioned base material according to the present invention has heat resistance, and the effect of suppressing the occurrence of residual stress during thermosetting is preferably exerted. Is preferred.

  The protective film-forming layer preferably contains a binder polymer component (A) and a curable component (B).

(A) Binder polymer component The binder polymer component (A) is used for imparting sufficient adhesion and film forming property (sheet forming property) to the protective film forming layer. As the binder polymer component (A), conventionally known acrylic polymers, polyester resins, urethane resins, acrylic urethane resins, silicone resins, rubber-based polymers, and the like can be used.

  The weight average molecular weight (Mw) of the binder polymer component (A) is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,200,000. If the weight average molecular weight of the binder polymer component (A) is too low, the adhesive force between the protective film-forming layer and the substrate film becomes high, and transfer failure of the protective film-forming layer may occur. In some cases, the adhesiveness of the protective film decreases, and transfer to a chip or the like becomes impossible, or the protective film peels off from the chip or the like after transfer.

  An acrylic polymer is preferably used as the binder polymer component (A). The glass transition temperature (Tg) of the acrylic polymer is preferably -60 to 50 ° C, more preferably -50 to 40 ° C, and particularly preferably -40 to 30 ° C. If the glass transition temperature of the acrylic polymer is too low, the peeling force between the protective film-forming layer and the base film may increase, resulting in poor transfer of the protective film-forming layer. It may be lowered and cannot be transferred to the chip or the like, or the protective film may be peeled off from the chip or the like after transfer.

  As a monomer which comprises the said acrylic polymer, a (meth) acrylic acid ester monomer or its derivative (s) is mentioned. For example, alkyl (meth) acrylates having 1 to 18 carbon atoms in the alkyl group, specifically methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl Examples include (meth) acrylate. In addition, (meth) acrylate having a cyclic skeleton, specifically cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, Examples include dicyclopentenyloxyethyl (meth) acrylate and imide (meth) acrylate. Furthermore, examples of the monomer having a functional group include hydroxymethyl (meth) acrylate having a hydroxyl group, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and the like; in addition, glycidyl (meth) having an epoxy group. An acrylate etc. are mentioned. As the acrylic polymer, an acrylic polymer containing a monomer having a hydroxyl group is preferable because of its good compatibility with the curable component (B) described later. The acrylic polymer may be copolymerized with acrylic acid, methacrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, or the like.

  Furthermore, you may mix | blend the thermoplastic resin for maintaining the flexibility of the protective film after hardening as a binder polymer component (A). Such a thermoplastic resin preferably has a weight average molecular weight of 1,000 to 100,000, more preferably 3,000 to 80,000. The glass transition temperature of the thermoplastic resin is preferably -30 to 120 ° C, more preferably -20 to 120 ° C. Examples of the thermoplastic resin include polyester resin, urethane resin, phenoxy resin, polybutene, polybutadiene, and polystyrene. These thermoplastic resins can be used individually by 1 type or in mixture of 2 or more types. By containing the above thermoplastic resin, the protective film forming layer follows the transfer surface of the protective film forming layer, and generation of voids or the like can be suppressed.

(B) Curable component The curable component (B) is a thermosetting component and / or an energy beam curable component.

  As the thermosetting component, a thermosetting resin and a thermosetting agent are used. As the thermosetting resin, for example, an epoxy resin is preferable.

  A conventionally well-known epoxy resin can be used as an epoxy resin. Specific examples of epoxy resins include polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, orthocresol novolac epoxy resins, dicyclopentadiene type epoxy resins, biphenyl type epoxy resins, and bisphenols. Examples thereof include epoxy compounds having two or more functional groups in the molecule, such as A-type epoxy resin, bisphenol F-type epoxy resin, and phenylene skeleton-type epoxy resin. These can be used individually by 1 type or in combination of 2 or more types.

  In the protective film forming layer, the thermosetting resin is preferably 1 to 1000 parts by weight, more preferably 10 to 500 parts by weight, and particularly preferably 20 to 200 parts by weight with respect to 100 parts by weight of the binder polymer component (A). included. When the content of the thermosetting resin is less than 1 part by mass, sufficient adhesiveness may not be obtained. When the content exceeds 1000 parts by mass, the peeling force between the protective film-forming layer and the base film becomes high, and the protective film A transfer defect of the formation layer may occur.

  The thermosetting agent functions as a curing agent for thermosetting resins, particularly epoxy resins. A preferable thermosetting agent includes a compound having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an acid anhydride. Of these, phenolic hydroxyl groups, amino groups, acid anhydrides and the like are preferable, and phenolic hydroxyl groups and amino groups are more preferable.

  Specific examples of the phenolic curing agent include polyfunctional phenolic resin, biphenol, novolac type phenolic resin, dicyclopentadiene type phenolic resin, zylock type phenolic resin, and aralkylphenolic resin. A specific example of the amine curing agent is DICY (dicyandiamide). These can be used individually by 1 type or in mixture of 2 or more types.

  It is preferable that content of a thermosetting agent is 0.1-500 mass parts with respect to 100 mass parts of thermosetting resins, and it is more preferable that it is 1-200 mass parts. If the content of the thermosetting agent is small, the adhesiveness may not be obtained due to insufficient curing, and if it is excessive, the moisture absorption rate of the protective film forming layer may increase and the reliability of the semiconductor device may be reduced.

  When the protective film forming layer contains a thermosetting component as the curable component (B), the protective film forming layer has thermosetting properties. In this case, the protective film forming layer can be cured by heating. However, the dicing sheet with the protective film forming layer of the present invention has a heat resistance, so that the heat of the protective film forming layer can be reduced. It is difficult for a residual stress to occur in the base material during curing to cause a problem.

  As the energy ray curable component, a low molecular compound (energy ray polymerizable compound) containing an energy ray polymerizable group and polymerized and cured when irradiated with energy rays such as ultraviolet rays and electron beams can be used. Specific examples of such energy ray-curable components include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, or 1,4-butylene glycol. Examples include acrylate compounds such as diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy-modified acrylate, polyether acrylate, and itaconic acid oligomer. Such a compound has at least one polymerizable double bond in the molecule, and usually has a weight average molecular weight of about 100 to 30,000, preferably about 300 to 10,000. The amount of the energy beam polymerizable compound is preferably 1 to 1500 parts by mass, more preferably 10 to 500 parts by mass, and particularly preferably 20 to 200 parts by mass with respect to 100 parts by mass of the binder polymer component (A). .

  Further, as the energy ray curable component, an energy ray curable polymer in which an energy ray polymerizable group is bonded to the main chain or side chain of the binder polymer component (A) may be used. Such an energy ray curable polymer has a function as a binder polymer component (A) and a function as a curable component (B).

  The main skeleton of the energy ray curable polymer is not particularly limited, and may be an acrylic polymer widely used as the binder polymer component (A), and may be a polyester, a polyether, etc. In view of easy control of physical properties, it is particularly preferable to use an acrylic polymer as the main skeleton.

  The energy beam polymerizable group bonded to the main chain or side chain of the energy beam curable polymer is, for example, a group containing an energy beam polymerizable carbon-carbon double bond, specifically a (meth) acryloyl group or the like. Can be illustrated. The energy beam polymerizable group may be bonded to the energy beam curable polymer via an alkylene group, an alkyleneoxy group, or a polyalkyleneoxy group.

  The weight average molecular weight (Mw) of the energy beam curable polymer to which the energy beam polymerizable group is bonded is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. The glass transition temperature (Tg) of the energy ray curable polymer is preferably in the range of −60 to 50 ° C., more preferably −50 to 40 ° C., and particularly preferably −40 to 30 ° C.

  The energy ray curable polymer includes, for example, an acrylic polymer containing a functional group such as hydroxyl group, carboxyl group, amino group, substituted amino group, and epoxy group, a substituent that reacts with the functional group, and energy ray polymerizable carbon. -Obtained by reacting a polymerizable group-containing compound having 1 to 5 carbon double bonds per molecule. Examples of the substituent that reacts with the functional group include an isocyanate group, a glycidyl group, and a carboxyl group.

  Examples of the polymerizable group-containing compound include (meth) acryloyloxyethyl isocyanate, meta-isopropenyl-α, α-dimethylbenzyl isocyanate, (meth) acryloyl isocyanate, allyl isocyanate, glycidyl (meth) acrylate, (meth) acrylic acid, and the like. Is mentioned.

  Acrylic polymer is a (meth) acrylic monomer having functional groups such as hydroxyl group, carboxyl group, amino group, substituted amino group, and epoxy group, or a derivative thereof, and other (meth) acrylic acid ester monomers copolymerizable therewith. Or it is preferable that it is a copolymer which consists of its derivative (s).

  Examples of the (meth) acrylic monomer having a functional group such as a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, or an epoxy group or a derivative thereof include 2-hydroxyethyl (meth) acrylate having a hydroxyl group, 2-hydroxy Examples thereof include propyl (meth) acrylate; acrylic acid having a carboxyl group, methacrylic acid, itaconic acid; glycidyl methacrylate having an epoxy group, glycidyl acrylate, and the like.

  Examples of other (meth) acrylic acid ester monomers or derivatives thereof copolymerizable with the above monomers include alkyl (meth) acrylates having an alkyl group having 1 to 18 carbon atoms, specifically methyl (meth) acrylate. , Ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and the like; (meth) acrylate having a cyclic skeleton, specifically cyclohexyl (meth) acrylate, Examples include benzyl (meth) acrylate, isobornyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, and imide acrylate. The acrylic polymer may be copolymerized with vinyl acetate, acrylonitrile, styrene or the like.

  Even in the case of using an energy ray curable polymer, the aforementioned energy ray polymerizable compound may be used in combination, or the binder polymer component (A) may be used in combination. The relationship between the amounts of these three components in the protective film-forming layer in the present invention is preferably an energy ray polymerizable compound with respect to 100 parts by mass of the sum of the masses of the energy ray curable polymer and the binder polymer component (A). 1 to 1500 parts by mass, more preferably 10 to 500 parts by mass, particularly preferably 20 to 200 parts by mass.

  By imparting energy beam curability to the protective film forming layer, the protective film forming layer can be cured easily and in a short time, and the production efficiency of the chip with protective film is improved. Conventionally, a protective film for a chip is generally formed of a thermosetting resin such as an epoxy resin, but the curing temperature of the thermosetting resin exceeds 200 ° C., and the curing time requires about 2 hours. It was an obstacle to improving production efficiency. However, since the energy ray-curable protective film forming layer is cured in a short time by energy ray irradiation, a protective film can be easily formed, which can contribute to improvement in production efficiency.

The other component protective film forming layer may contain the following components in addition to the binder polymer component (A) and the curable component (B).

(C) It is preferable that a coloring agent protective film formation layer contains a coloring agent (C). By blending a colorant into the protective film forming layer, when a semiconductor device is incorporated in equipment, infrared rays generated from surrounding devices can be shielded, and malfunction of the semiconductor device due to them can be prevented. Visibility of characters when a product number or the like is printed on a protective film obtained by curing the protective film forming layer is improved. That is, in a semiconductor device or semiconductor chip on which a protective film is formed, the product number or the like is usually printed on the surface of the protective film by a laser marking method (a method in which the surface of the protective film is scraped off by laser light and printed). By containing the colorant (C), a sufficient difference in contrast between the portion of the protective film scraped by the laser beam and the portion that is not removed is obtained, and the visibility is improved. As the colorant (C), organic or inorganic pigments and dyes are used. Among these, black pigments are preferable from the viewpoint of electromagnetic wave and infrared shielding properties. Examples of the black pigment include carbon black, iron oxide, manganese dioxide, aniline black, activated carbon, and the like, but are not limited thereto. Carbon black is particularly preferable from the viewpoint of increasing the reliability of the semiconductor device. A colorant (C) may be used individually by 1 type, and may be used in combination of 2 or more type. The high curability of the protective film-forming layer in the present invention is particularly preferably exhibited when a colorant that lowers the transmittance of both visible light and / or infrared rays and ultraviolet rays is used, and the ultraviolet ray permeability is lowered. . In addition to the above-mentioned black pigment, the colorant that reduces the transparency of both visible light and / or infrared and ultraviolet rays has an absorptivity or reflectivity in the visible light and / or infrared and ultraviolet wavelength regions. If it has, it will not specifically limit.

  The blending amount of the colorant (C) is preferably 0.1 to 35 parts by mass, more preferably 0.5 to 25 parts by mass, particularly preferably 100 parts by mass of the total solid content constituting the protective film forming layer. Is 1-15 parts by mass.

(D) Curing accelerator The curing accelerator (D) is used to adjust the curing rate of the protective film forming layer. The curing accelerator (D) is preferably used particularly when the epoxy resin and the thermosetting agent are used in combination in the curable component (B).

  Preferred curing accelerators include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl- Imidazoles such as 4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole; Organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine; And tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphinetetraphenylborate. These can be used individually by 1 type or in mixture of 2 or more types.

  The curing accelerator (D) is preferably contained in an amount of 0.01 to 10 parts by mass, more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the curable component (B). By containing the curing accelerator (D) in an amount within the above range, it has excellent adhesive properties even when exposed to high temperatures and high humidity, and has high reliability even when exposed to severe reflow conditions. Can be achieved. If the content of the curing accelerator (D) is low, sufficient adhesion characteristics cannot be obtained due to insufficient curing, and if it is excessive, the curing accelerator having a high polarity will adhere to the protective film forming layer under high temperature and high humidity. The reliability of the semiconductor device is lowered by moving to the side and segregating.

(E) Coupling agent The coupling agent (E) may be used to improve the adhesion, adhesion and / or cohesion of the protective film to the chip of the protective film forming layer. Moreover, the water resistance can be improved by using a coupling agent (E), without impairing the heat resistance of the protective film obtained by hardening | curing a protective film formation layer.

  As the coupling agent (E), a compound having a group that reacts with a functional group of the binder polymer component (A), the curable component (B), or the like is preferably used. As the coupling agent (E), a silane coupling agent is desirable. Such coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (methacryloxypropyl). ) Trimethoxysilane, γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N- Phenyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltrimethoxy Silane, meth Examples include rutriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane. These can be used individually by 1 type or in mixture of 2 or more types.

  The coupling agent (E) is usually 0.1 to 20 parts by mass, preferably 0.2 to 10 parts by mass, with respect to 100 parts by mass in total of the binder polymer component (A) and the curable component (B). Preferably, it is contained at a ratio of 0.3 to 5 parts by mass. If the content of the coupling agent (E) is less than 0.1 parts by mass, the above effect may not be obtained, and if it exceeds 20 parts by mass, it may cause outgassing.

(F) Inorganic filler By blending the inorganic filler (F) in the protective film forming layer, it is possible to adjust the thermal expansion coefficient in the protective film after curing, and the protective film after curing with respect to the semiconductor chip The reliability of the semiconductor device can be improved by optimizing the thermal expansion coefficient. Moreover, it becomes possible to reduce the moisture absorption rate of the protective film after hardening.

  Preferable inorganic fillers include powders such as silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, beads formed by spheroidizing them, single crystal fibers, and glass fibers. Among these, silica filler and alumina filler are preferable. The said inorganic filler (F) can be used individually or in mixture of 2 or more types. Content of an inorganic filler (F) can be normally adjusted in 1-80 mass parts with respect to 100 mass parts of total solids which comprise a protective film formation layer.

(G) When the photopolymerization initiator protective film forming layer contains an energy ray curable component as the curable component (B) described above, an energy ray such as an ultraviolet ray is irradiated on the use of the energy ray curable component. Curing the curable component. In this case, the polymerization curing time and the amount of light irradiation can be reduced by including the photopolymerization initiator (G) in the composition.

  Specific examples of such photopolymerization initiator (G) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal. 2,4-diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1,2-diphenylmethane, 2-hydroxy- 2-methyl-1- [4- (1-methylvinyl) phenyl] propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and β-alkyl Examples thereof include roll anthraquinone. A photoinitiator (G) can be used individually by 1 type or in combination of 2 or more types.

  It is preferable that 0.1-10 mass parts is contained with respect to 100 mass parts of energy-beam curable components, and, as for the mixture ratio of a photoinitiator (G), it is more preferable that 1-5 mass parts is contained. If the amount is less than 0.1 parts by mass, satisfactory transferability may not be obtained due to insufficient photopolymerization. If the amount exceeds 10 parts by mass, a residue that does not contribute to photopolymerization is generated, and the curability of the protective film forming layer is increased. May be insufficient.

(H) In order to adjust the initial adhesive force and cohesive force of the crosslinker protective film forming layer, a crosslinker may be added. Examples of the crosslinking agent (H) include organic polyvalent isocyanate compounds and organic polyvalent imine compounds.

  Examples of the organic polyvalent isocyanate compound include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, alicyclic polyvalent isocyanate compounds, trimers of these organic polyvalent isocyanate compounds, and these organic polyvalent isocyanate compounds. And a terminal isocyanate urethane prepolymer obtained by reacting a polyol compound with a polyol compound.

  Examples of organic polyvalent isocyanate compounds include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4′-diisocyanate, diphenylmethane. -2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, trimethylolpropane adduct tolylene diisocyanate and lysine Isocyanates.

  Examples of the organic polyvalent imine compound include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri -Β-aziridinylpropionate and N, N′-toluene-2,4-bis (1-aziridinecarboxyamide) triethylenemelamine can be exemplified.

  The crosslinking agent (H) is usually from 0.01 to 20 parts by weight, preferably from 0.1 to 10 parts by weight, more preferably from 100 parts by weight of the total amount of the binder polymer component (A) and the energy ray curable polymer. It is used at a ratio of 0.5 to 5 parts by mass.

(I) In addition to the above, various additives may be blended in the general-purpose additive protective film forming layer as necessary. Examples of various additives include leveling agents, plasticizers, antistatic agents, antioxidants, ion scavengers, gettering agents, chain transfer agents, and the like.

  The protective film forming layer composed of each component as described above has adhesiveness and curability, and is easily adhered by being pressed against a work (semiconductor wafer, chip, etc.) in an uncured state. Then, after curing, a protective film having high impact resistance can be provided, the adhesive strength is excellent, and a sufficient protective function can be maintained even under severe high temperature and high humidity conditions. The protective film forming layer may have a single layer structure, or may have a multilayer structure as long as one or more layers containing the above components are included.

  The thickness of the protective film forming layer is not particularly limited, but is preferably 3 to 300 μm, more preferably 5 to 250 μm, and particularly preferably 7 to 200 μm.

  The maximum transmittance at a wavelength of 300 to 1200 nm, which is a scale showing the transmittance of visible light and / or infrared rays and ultraviolet rays in the protective film forming layer, is preferably 20% or less, more preferably 0 to 15%. More preferably, it is more than 0% and 10% or less, particularly preferably 0.001 to 8%. By setting the maximum transmittance of the protective film forming layer at a wavelength of 300 to 1200 nm in the above range, when the protective film forming layer contains an energy ray curable component (particularly an ultraviolet curable component), the protective film forming layer is Even if it is colored, the curability is excellent. Further, the transmittance in the visible light wavelength region and / or the infrared wavelength region is lowered, and effects such as prevention of malfunction caused by infrared rays of the semiconductor device and improvement in printing visibility can be obtained. The maximum transmittance of the protective film forming layer at a wavelength of 300 to 1200 nm can be adjusted by the colorant (C). In addition, the maximum transmittance of the protective film forming layer is the total light transmission at 300 to 1200 nm of the cured protective film forming layer (thickness 25 μm) using a UV-vis spectrum inspection apparatus (manufactured by Shimadzu Corporation). The transmittance was measured, and the highest transmittance (maximum transmittance) was obtained.

(Peeling sheet)
The dicing sheet with a protective film forming layer may be provided with a release sheet for avoiding contact with the outside of the surface until it is used. As the release sheet, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene terephthalate film, Polyurethane film, ethylene vinyl acetate copolymer film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film, polycarbonate film, polyimide film, fluorine A transparent film such as a resin film is used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient. Moreover, the film which colored these, an opaque film, etc. can be used. Further, the release sheet may be subjected to a release treatment on one side. Examples of the release agent used for the release treatment include release agents such as silicone-based, fluorine-based, and long-chain alkyl group-containing carbamates.

  In order to release the surface of the release sheet using the release agent described above, the release agent can be applied directly with a gravure coater, Meyer bar coater, air knife coater, roll coater, etc. without solvent, or by solvent dilution or emulsion. Then, a laminate may be formed by room temperature or heat curing or electron beam curing, wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, or the like.

  The thickness of the release sheet is usually about 10 to 500 μm, preferably about 15 to 300 μm, and particularly preferably about 20 to 250 μm. Moreover, the thickness of the dicing sheet with a protective film forming layer is usually 1 to 500 μm, preferably 5 to 300 μm, and particularly preferably about 10 to 150 μm.

(Dicing sheet with protective film forming layer)
The following method is mentioned as a manufacturing method of a dicing sheet with a protective film formation layer. First, a protective film forming layer is formed on the release sheet. The protective film-forming layer is obtained by applying and drying a protective film-forming layer composition obtained by mixing the above-described components in an appropriate solvent on an appropriate release sheet. In addition, a composition for a protective film forming layer is applied onto a release sheet, dried to form a film, and this is bonded to another release sheet and sandwiched between two release sheets (release sheet / protective film) Forming layer / release sheet).

  Next, in the state of being sandwiched between two release sheets, one release sheet is released. Then, it is punched into a circle that is the same size or slightly larger than the workpiece (for example, a semiconductor wafer) to which the protective film forming layer is to be attached, and the periphery of the protective film forming layer that has been punched in a circular shape is removed. Next, a circular protective film-forming layer is stuck on the separately prepared base film, and the other release sheet is peeled off.

  Next, an adhesive layer is prepared. Since the pressure-sensitive adhesive layer is usually punched before being laminated with the base film, it is provided in a form in which release sheets treated with a silicone-based release agent are laminated on both sides. Is done. The release sheet plays a role of protecting the pressure-sensitive adhesive layer and providing support. If the release sheets laminated on both sides are configured to have a difference in release force as in the light release type and the heavy release type, the workability at the time of creating the dicing sheet with the protective film forming layer is preferably improved. That is, as a release sheet, a light release type release sheet and a heavy release type release sheet are used to sandwich an adhesive layer, and a light release type release sheet side is used to remove a light release type release sheet. The pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer are punched in a circular shape, and the light release type release sheet and the pressure-sensitive adhesive layer punched in a circular shape are scraped to form an opening. Next, the light release type release sheet on the adhesive layer surrounding the opening is removed to expose the adhesive layer. Then, the base film on which the protective film forming layer obtained above is laminated and the exposed surface of the pressure-sensitive adhesive layer so that the circularly punched opening and the circular protective film forming layer are concentric Are laminated to form a laminate.

  Thereafter, in accordance with the outer diameter of the margin for the ring frame, the die is cut concentrically with the opening and the protective film forming layer, and the periphery of the die-cut laminate is removed. Finally, the heavy release type release sheet is released to obtain the dicing sheet with a protective film forming layer of the present invention. As shown in FIG. 1, the dicing sheet 10 with a protective film forming layer of the present invention includes a base film 1, a protective film forming layer 4 formed on the inner periphery of the base film 1, and the base film 1. The pressure-sensitive adhesive layer 2 is formed on the outer periphery, and is attached to the ring frame 5 by the pressure-sensitive adhesive layer 2. The inner diameter (opening diameter) of the annular pressure-sensitive adhesive layer 2 formed on the outer peripheral portion of the base film 1 is formed to be larger than the outer diameter of the protective film forming layer 4. The width of the pressure-sensitive adhesive layer 2 formed in an annular shape is preferably 0.5 to 20 mm.

(Chip manufacturing method)
Next, a method of using the dicing sheet with a protective film forming layer according to the present invention will be described taking as an example the case where the sheet is applied to the manufacture of a chip (for example, a semiconductor chip).

A manufacturing method of a semiconductor chip using a dicing sheet with a protective film forming layer according to the present invention is a method in which a protective film forming layer of the above sheet is pasted on the back surface of a semiconductor wafer (work) on which a circuit is formed. The steps (1) to (3) are performed in the order of (1), (2), and (3) to obtain a semiconductor chip having a protective film on the back surface.
Step (1): The protective film forming layer is cured to obtain a protective film.
Step (2): dicing the semiconductor wafer (workpiece) and the protective film,
Step (3): The protective film and the base film are peeled off.

The semiconductor chip manufacturing method according to the present invention further includes the following step (4) in addition to the steps (1) to (3), and further includes the step (4) after the step (1). It can also be done.
Step (4): Laser printing on the protective film.

  The step (4) is preferably performed between the step (1) and the step (2). By performing laser printing on the protective film-forming layer (protective film) after curing, the printing accuracy is excellent. On the other hand, when the process is performed after the process (2) and before the process (3), the printing accuracy may be deteriorated due to a minute positional deviation of the chip during dicing. Moreover, when it is performed after the step (3), it is necessary to individually perform laser printing on each chip, and the process becomes complicated.

  The semiconductor wafer may be a silicon wafer or a compound semiconductor wafer such as gallium / arsenic. Formation of a circuit on the wafer surface can be performed by various methods including conventionally used methods such as an etching method and a lift-off method. Next, the opposite surface (back surface) of the circuit surface of the semiconductor wafer is ground. The grinding method is not particularly limited, and grinding may be performed by a known means using a grinder or the like. At the time of back surface grinding, an adhesive sheet called a surface protection sheet is attached to the circuit surface in order to protect the circuit on the surface. In the back surface grinding, the circuit surface side (that is, the surface protection sheet side) of the wafer is fixed by a chuck table or the like, and the back surface side on which no circuit is formed is ground by a grinder. The thickness of the wafer after grinding is not particularly limited, but is usually about 20 to 500 μm. Thereafter, if necessary, the crushed layer generated during back grinding is removed. The crushed layer is removed by chemical etching, plasma etching, or the like.

  Subsequently, the protective film formation layer of the said dicing sheet with a protective film formation layer is affixed on the back surface of a semiconductor wafer. Then, process (1)-(3) is performed in order of (1), (2), (3). This process is described below.

  First, the protective film formation layer of the said dicing sheet with a protective film formation layer is affixed on the back surface of the semiconductor wafer in which the circuit was formed on the surface. Next, the protective film forming layer is cured, and a protective film is formed on the entire surface of the wafer. By sticking the protective film-forming layer before curing to the semiconductor wafer, the protective film-forming layer is well adapted to the sticking surface of the wafer, and the adhesion between the protective film and the semiconductor chip is improved. In addition, shrinkage deformation of the dicing sheet with the protective film forming layer is suppressed when the protective film forming layer is cured. Since the protective film forming layer contains the curable component (B), the protective film forming layer is generally cured by heat curing or energy ray irradiation. In addition, when the thermosetting component and the energy ray curable component are blended in the protective film forming layer, the protective film forming layer can be cured by both heating and energy ray irradiation. Curing by beam irradiation may be performed simultaneously or sequentially. As a result, a protective film made of a cured resin is formed on the back surface of the wafer, and the strength is improved as compared with the case of the wafer alone, so that damage to the thin wafer during handling can be reduced. In addition, the thickness of the protective film is excellent compared to a coating method in which a coating liquid for the protective film is directly applied to the back surface of the wafer or chip.

  When the protective film forming layer is thermosetting, the occurrence of residual stress of the base film due to deformation during the thermosetting of the dicing sheet with the protective film forming layer of the present invention is suppressed, and the chip interval after dicing is reduced. The effect of preventing narrowing is preferably exhibited. Therefore, the protective film forming layer is thermosetting, and the manufacturing method of performing dicing and pickup (peeling of the adhesive sheet from the protective film) after the thermosetting of the protective film forming layer, that is, (1), (2), It is preferable to use the dicing sheet with a protective film forming layer of the present invention in the production method in which the steps are performed in the order of (3).

  Next, it is preferable to perform laser printing on the cured protective film forming layer (protective film). Laser printing is performed by a laser marking method, and the protective film is marked with a product number or the like by scraping the surface of the protective film over the base film by irradiation with laser light. According to the dicing sheet with a protective film forming layer of the present invention, since the warpage of the wafer can be suppressed even with an extremely thin wafer, the focal point of the laser beam is accurately determined and marking can be performed with high accuracy.

  Subsequently, the laminated body (laminated body of a semiconductor wafer, a protective film, and a base film) of a semiconductor wafer and a dicing sheet with a protective film forming layer is diced for each circuit formed on the wafer surface. Dicing is performed so as to cut both the wafer and the protective film. Dicing is not particularly limited. For example, after dicing the wafer, the peripheral portion of the dicing sheet with the protective film forming layer (the outer peripheral portion of the base film) is fixed with a ring frame, and then a rotating round blade such as a dicing blade is used. For example, a method of forming a wafer into a chip by a known method such as The depth of cut into the pressure-sensitive adhesive sheet by dicing is only required to completely cut the protective film forming layer, and is preferably 0 to 30 μm or less from the interface with the protective film forming layer. By reducing the amount of cut into the base film, it is possible to suppress the melting of the base film due to the friction of the dicing blade and the occurrence of burrs in the base film. Moreover, since the base film in this invention has the said physical property, it is excellent in heat resistance. As a result, even if the protective film forming layer is exposed to a high temperature in the curing step, the deformation is suppressed, and the semiconductor wafer with the protective film can be diced on the base film. When the base film is deformed, the chip interval tends to be narrowed due to the residual stress resulting from the deformation.

  Thereafter, the diced semiconductor chip with a protective film is picked up by a general-purpose means such as a collet, whereby the protective film and the base film are peeled off. As a result, a semiconductor chip having a protective film on the back surface (semiconductor chip with protective film) is obtained. According to the present invention as described above, a protective film having high thickness uniformity can be easily formed on the back surface of the chip, and cracks after the dicing process and packaging are less likely to occur. In addition, according to the present invention, a chip with a protective film is obtained without replacing the wafer on which the protective film is formed with the dicing tape, as compared with the conventional process in which the wafer is diced. Therefore, the manufacturing process can be simplified. Further, since the wafer weakened by grinding is not handled alone, the risk of wafer breakage is reduced. Further, the thinned wafer may be warped due to curing shrinkage of the protective film. However, since the wafer is held on the ring frame via the adhesive sheet, the warpage can be suppressed. Then, the semiconductor device can be manufactured by mounting the semiconductor chip on a predetermined base by the face-down method. Further, a semiconductor device can be manufactured by adhering a semiconductor chip having a protective film on the back surface to another member (on the chip mounting portion) such as a die pad portion or another semiconductor chip.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In the following examples and comparative examples, <chip spacing retention>, <total light transmittance at wavelengths of 532 nm and 1064 nm>, <laser printing evaluation>, and <thermal shrinkage of substrate film> are as follows: Measured and evaluated. Moreover, the following <composition for protective film formation layer> and <adhesive composition> were used.

<Chip spacing retention>
The protective film forming layer of the dicing sheet with protective film forming layer was attached to a silicon wafer (diameter 8 inches, thickness 200 μm, # 2000 polishing), and the adhesive layer on the outer peripheral portion of the adhesive sheet was attached to a ring frame. Subsequently, it heated at 130 degreeC for 2 hours, the protective film formation layer was hardened, and the silicon wafer with a protective film was diced into the chip size of 5 mm x 5 mm. The width of the dicing blade used for dicing is 30 μm. At this time, the distance between adjacent chips was measured with a digital microscope at the time after dicing. The measurement was performed with respect to the distance between the chip adjacent in the vertical direction (the chip adjacent on the lower side) and the chip adjacent in the horizontal direction (the chip on the right side), and the average of the measurement results of the five chips was taken. The case where the distance between the chips was 20 μm or more was evaluated as “A”, the case where it was less than 20 μm was evaluated as “B”, and the case where it was less than 10 μm was evaluated as “C”.

<Total light transmittance at wavelengths of 532 nm and 1064 nm>
Using a UV-vis spectrum inspection apparatus (manufactured by Shimadzu Corporation), the total light transmittance at wavelengths of 532 nm and 1064 nm of the base film in the dicing sheet with a protective film forming layer was measured.

<Laser printing evaluation>
As in the evaluation of the chip spacing retention, the protective film forming layer of the dicing sheet with the protective film forming layer was attached to the silicon wafer, the adhesive layer was attached to the ring frame, and the protective film forming layer was heat-cured. Next, using a YAG laser marker (LM5000 manufactured by Hitachi Construction Machinery Finetech Co., Ltd., laser wavelength: 532 nm), laser printing was performed on the protective film over the base film. Thereafter, the base film was peeled off, and it was confirmed whether or not the characters printed on the protective film could be read by the CCD camera. The case where reading was possible was evaluated as “A”, and the case where reading was not possible was evaluated as “B”. The character size was 400 μm wide and 200 μm wide.

<Melting point of base film>
The melting point of the base film was measured by a method based on JIS K7121; 1987.

<Heat shrinkage of base film>
The base film was cut into 10 cm × 10 cm and placed in a hot air oven (130 ° C., 2 hours). Thereafter, the base film was taken out, the dimensions of the base film were measured, and the thermal shrinkage rate was determined by the following formula.
Thermal shrinkage (%) = {(Area of base film before input) − (Area of base film after input)} / Area of base film before input × 100

<Composition for protective film forming layer>
Each component and blending amount constituting the protective film forming layer are shown below (each component / blending amount).
(A) Binder polymer component: acrylic polymer consisting of 55 parts by mass of n-butyl acrylate, 15 parts by mass of methyl methacrylate, 20 parts by mass of glycidyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate (weight average molecular weight: 900,000, glass transition (Temperature: -28 ° C) / 100 parts by mass (B) curable component (B1) 50 parts by mass of bisphenol A type epoxy resin (epoxy equivalent 180 to 200 g / eq), dicyclopentadiene type epoxy resin (Dainippon Ink and Chemicals, Inc.) (Epicron HP-7200HH) 50 parts by mass, thermosetting component / (total 100 parts by mass)
(B2) Thermally active latent epoxy resin curing agent (dicyandiamide (Adeka Hardener 3636AS manufactured by Asahi Denka) /2.8 parts by mass (C) Colorant: carbon black / 10.0 parts by mass (D) curing accelerator (2- Phenyl-4,5-dihydroxymethylimidazole (Cureazole 2PHZ manufactured by Shikoku Kasei Kogyo Co., Ltd.) / 2.8 parts by mass (E) Coupling agent: Silane coupling agent (A-1110 manufactured by Nihon Unicar) / 1 part by mass (F) Inorganic filler: silica filler (fused quartz filler (average particle size 8 μm) / 300 parts by mass

<Adhesive composition>
Silicone pressure-sensitive adhesive comprising 100 parts by mass of silicone CF-2017 manufactured by Toray Dow Corning Co., Ltd. and 1 part by mass of SRX212 manufactured by Toray Dow Silicone Co., Ltd.

Example 1
Each said component of the composition for protective film formation layers was mix | blended with the said compounding quantity. Moreover, the polyethylene terephthalate film (SP-P502010 by Lintec Corporation, thickness 50micrometer) which peeled on one side was prepared as a peeling sheet.

  A methyl ethyl ketone solution (solid concentration: 61% by weight) of the composition for forming a protective film is applied onto the release-treated surface of the release sheet so as to have a thickness of 25 μm and dried (drying condition: 120 ° C. in an oven). 3 minutes) to form a protective film forming layer on the release sheet. To this protective film forming layer, a release treatment surface of a polyethylene terephthalate film (SP-PET 381031, thickness 38 μm) was bonded as another release sheet. Next, the die is cut to the same size as the silicon wafer (diameter 8 inches) so as to cut only the protective film forming layer and other release sheets while leaving the release sheet, and then protection of the portion excluding the die-cut shape portion. The film-forming layer and other release sheets were removed, and a protective film-forming layer and other release sheets that were punched in a circle on the release sheet were obtained.

  A polyimide film having a thickness of 50 μm (Kapton 200H manufactured by Toray DuPont Co., Ltd.) was prepared as a base film. Next, the other release sheet on the protective film forming layer was peeled off, and the base film and the protective film forming layer were laminated, and then the release sheet was removed.

  As a release sheet, a polyethylene terephthalate film (SP-PET38E-0010YC manufactured by Lintec Corporation) subjected to release treatment on one side was prepared, and a polyethylene terephthalate film (SP-PET38E-0010YC manufactured by Lintec Corporation) was prepared as another release sheet. After applying the toluene solution of the above-mentioned pressure-sensitive adhesive (solid concentration 35% by weight) on the release-treated surface of the release sheet so as to have a thickness of 5 μm and drying (drying conditions: 120 ° C. for 3 minutes in an oven), Another release sheet was bonded. Next, in accordance with the inner diameter of the ring frame, the die was cut in a circular shape from the other release sheet side, and the pressure-sensitive adhesive layer and the other release sheet were removed from the die-cut portion to form an opening. Next, the release sheet on the pressure-sensitive adhesive layer surrounding the opening is removed to expose the pressure-sensitive adhesive layer, and the above-described base film and pressure-sensitive adhesive are so formed that the opening and the protective film forming layer are concentric. The exposed surface of the layer was laminated to obtain a laminate.

  The outer diameter of the glue for the ring frame was set to 260 mm so that the outer diameter (275 mm) of the ring frame was not exceeded, and the laminate was die-cut in this size concentrically with the opening and the protective film forming layer. Thereafter, the remaining release sheet was peeled off to obtain a dicing sheet with a protective film forming layer. Each evaluation result is shown in Table 1.

(Example 2)
As a base film, an unstretched polypropylene film (RS82 # 70 manufactured by Santox Co., Ltd.) subjected to a peeling treatment with a thickness of 70 μm is used, and a protective film forming layer and a pressure-sensitive adhesive layer are laminated on the surface not subjected to the peeling treatment A dicing sheet with a protective film forming layer was obtained in the same manner as in Example 1 except that. Each evaluation result is shown in Table 1.

(Example 3)
A dicing sheet with a protective film forming layer was obtained in the same manner as in Example 1 except that a polybutylene terephthalate film having a thickness of 100 μm was used as the base film. Each evaluation result is shown in Table 1.

(Comparative Example 1)
A dicing sheet with a protective film forming layer was obtained in the same manner as in Example 1 except that a corona-treated polyethylene film having a thickness of 110 μm was used as the base film, and a protective film forming layer and an adhesive layer were laminated on the corona-treated surface. It was. The polyethylene film melted when the protective film-forming layer was heated and cured, and the evaluation of the chip spacing retention and the laser printability could not be performed. Further, the heat shrinkage rate could not be measured. Each evaluation result is shown in Table 1.

(Comparative Example 2)
As a base film, an unstretched polypropylene film (RS72 # 75 manufactured by Santox Co., Ltd.) subjected to a peeling treatment with a thickness of 75 μm was used, and a protective film forming layer and an adhesive layer were laminated on the surface not subjected to the peeling treatment. A dicing sheet with a protective film forming layer was obtained in the same manner as Example 1 except for the above. Each evaluation result is shown in Table 1.

(Comparative Example 3)
A biaxially stretched polypropylene film (T234, manufactured by Mitsui Chemical Tosero Co., Ltd.) subjected to a peeling treatment with a thickness of 50 μm is used as a base film, and a protective film forming layer and a pressure-sensitive adhesive layer are laminated on the surface not subjected to the peeling treatment. A dicing sheet with a protective film forming layer was obtained in the same manner as in Example 1 except that. Each evaluation result is shown in Table 1.

DESCRIPTION OF SYMBOLS 1 ... Base film 2 ... Adhesive layer 3 ... Adhesive sheet 4 ... Protective film formation layer 5 ... Ring frame 10 ... Dicing sheet with protective film formation layer

Claims (9)

From the peeled base film (excluding the polyimide resin film) , the protective film forming layer formed on the inner peripheral portion of the base film, and the adhesive layer formed on the outer peripheral portion of the base film Become
The melting point of the base film exceeds 130 ° C. or does not have a melting point,
A dicing sheet with a protective film forming layer, wherein the base film has a thermal shrinkage of −1 to + 1% when heated at 130 ° C. for 2 hours.   The dicing sheet with a protective film forming layer according to claim 1, wherein the protective film forming layer is thermosetting.   The dicing sheet with a protective film forming layer according to claim 1 or 2, wherein the total light transmittance of the substrate film at a wavelength of 532 nm and a wavelength of 1064 nm is 70% or more.   The dicing sheet with a protective film forming layer according to any one of claims 1 to 3, wherein the protective film forming layer contains a binder polymer component (A) and a curable component (B). The protective film forming layer contains a colorant (C),
The maximum transmittance of the protective film forming layer at a wavelength of 300 to 1200 nm is 20% or less. The dicing sheet with a protective film forming layer according to any one of claims 1 to 4. The base film is at least one selected from a polypropylene film, a polybutylene terephthalate film, an annealed polyester film, a polycarbonate film, a polyphenylene sulfide film, a cycloolefin resin film, and a laminate of two or more of these. The dicing sheet with a protective film forming layer according to claim 1. The substrate film is an unstretched polypropylene film or a polybutylene terephthalate film. The dicing sheet with a protective film forming layer according to any one of claims 1 to 6. The protective film forming layer of the dicing sheet with a protective film forming layer according to any one of claims 1 to 7 is attached to a work, and the following steps (1) to (3) are performed as (1), (2), ( 3) Chip manufacturing method performed in the order of
Step (1): The protective film forming layer is cured to obtain a protective film.
Step (2): Dicing workpiece and protective film,
Step (3): The protective film and the base film are peeled off. The chip manufacturing method according to claim 8, wherein the following step (4) is further performed after the step (1);
Step (4): Laser printing on the protective film.

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